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introduce pickupstream tools

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sync golang ssh

x/crypto/ssh: ParsePrivateKey errors out with encrypted private keys

RSA and DSA keys if encrypted have the
phrase ENCRYPTED in their Proc-Type block
header according to RFC 1421 Section 4.6.1.1.

This CL checks for that phrase and errors out
if we encounter it, since we don't yet have
decryption of encrypted private keys.

Fixes golang/go#6650

Change-Id: I5b157716a2f93557d289af5f62994234a2e7a0ed
Reviewed-on: https://go-review.googlesource.com/29676
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh/terminal: implement ReadPassword and IsTerminal

Fixes golang/go#13085.

Change-Id: I2fcdd60e5e8db032d6fa3ce76198bdc7a63f3cf6
Reviewed-on: https://go-review.googlesource.com/16722
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

ssh: Consistent error handling in examples

After discussion around an example SFTP implementation:
https://github.com/pkg/sftp/pull/54
it has been suggested that errors should be handled using
log.Fatal rather than panic, and that the actual underlying error
should also be logged. In the existing SSH examples there
are several different styles of error handling using both panic
and log.Fatalf.

This patch uses log.Fatal consistently for all of these cases.

Change-Id: I2cebfae1821530dc3c5bbc46d451fe026bed582f
Reviewed-on: https://go-review.googlesource.com/16736
Reviewed-by: Russ Cox <rsc@golang.org>

x/crypto/ssh: public key authentication example

Fixes golang/go#13902.

Adds public key authentication to the
password authentication example.

Change-Id: I4af0ca627fb15b617cc1ba1c6e0954b013f4d94f
Reviewed-on: https://go-review.googlesource.com/29374
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh: fix height/width order in RequestPty example

The RequestPty function takes the size arguments in the order height,
then width, instead of the more common width, then height. 80 is a very
common width for a terminal, so when the example reads RequestPty(...,
80, 40, ...), it's easy to assume that the order is width-height.
Switching the order should make it more obvious what is going on.

Change-Id: I1d6266b1c0dcde5ee6e31a6d26d2dcaf14fec58a
Reviewed-on: https://go-review.googlesource.com/18290
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

ssh: add CryptoPublicKey interface, expose underlying crypto.PublicKey

When implemented by ssh.PublicKey types, the new CryptoPublicKey
interface exposes the public key in the the crypto.PublicKey form via a
CryptoPublicKey() method.

This is useful for example in a custom ServerConfig.PublicKeyCallback
function to check or record additional details about the underlying
crypto.PublicKey

Change-Id: I4429df42c6fc5119f7c0023a539aaa9c59648bba
Reviewed-on: https://go-review.googlesource.com/23974
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

sync with golang/ssh upstream

Allow hyphen-characters within usernames (#9)

* Allow hyphen-characters within usernames.

* Allow up to 32 characters for usernames.

ssh: bound DH public values to [2, p-2].

Previously this code bounded the values to [1, p-1]. This protects
against invalid values that could take lots of CPU time to calculate
with. But the standard bounding is [2, p-2] so mirror that.

Since the DH exchange is signed anyway, this is not a security fix.

Change-Id: Ibef01805a596a433b0699d7a09c076344fa8c070
Reviewed-on: https://go-review.googlesource.com/30590
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

crypto/ssh: fix comment for ssh.NewPublicKey

Change-Id: I88bb7859259c82cd77ab2d26b728143281761def
Reviewed-on: https://go-review.googlesource.com/25232
Reviewed-by: Russ Cox <rsc@golang.org>

x/crypto/ssh: Add FingerprintLegacyMD5 and FingerprintSHA256 methods

Implement a standards-compliant fingerprint format method (RFC 4716 section 4)
and a newer SHA256 fingerprint format method.

Fixes golang/go#12292

Change-Id: I4f3f8fc1d0a263cb3b0964d0078e69006a39d1a5
Reviewed-on: https://go-review.googlesource.com/32814
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

x/crypto/ssh/terminal: replace \n with \r\n.

911fafb28f4 made MakeRaw match C's behaviour. This included clearing the
OPOST flag, which means that one now needs to write \r\n for a newline,
otherwise the cursor doesn't move back to the beginning and the terminal
prints a staircase.

(Dear god, we're still emulating line printers.)

This change causes the terminal package to do the required
transformation.

Fixes golang/go#17364.

Change-Id: Ida15d3cf701a21eaa59161ab61b3ed4dee2ded46
Reviewed-on: https://go-review.googlesource.com/33902
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

crypto/ssh: use net.IP.Equal instead of bytes.Equal

A net.IP may be represented by both by a 4 as well as a 16 byte long
byte slice. Because of this, it is not safe to compare IP addresses
using bytes.Equal as the same IP address using a different internal
representation will produce mismatches.

Change-Id: I0d228771cf363ccfb9532f8bc2a2fc8eff61f6e9
Reviewed-on: https://go-review.googlesource.com/34450
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh/terminal: fix a typo

Change-Id: Iafe2ebb6d37afd2a64aa72750a722d4860bb735e
Reviewed-on: https://go-review.googlesource.com/34535
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

all: fix some vet warnings

Change-Id: I85c2912a6862c6c251450f2a0926ecd33a9fb8e7
Reviewed-on: https://go-review.googlesource.com/34815
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh/terminal: consistent return value for Restore

This patch makes the Restore function return nil
on success to be consistent with other functions
like MakeRaw.

Change-Id: I81e63f568787dd88466a5bb30cb87c4c3be75a5c
Reviewed-on: https://go-review.googlesource.com/34952
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

x/ssh: filter debug and ignore messages in transport.readPacket.

This prevents these messages from confusing higher layers of the
protocol.

Fixes #16927.

Change-Id: If18d8d02bdde3c0470e29a7280cd355d3e55ad78
Reviewed-on: https://go-review.googlesource.com/34959
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>

ssh: make client auth tests less chatty.

Change-Id: Ib35ce0e7437e32a3fa24a9330c479306b7fa6880
Reviewed-on: https://go-review.googlesource.com/35011
Reviewed-by: Adam Langley <agl@golang.org>

ssh: rewrite (re)keying logic.

Use channels and a dedicated write loop for managing the rekeying
process.  This lets us collect packets to be written while a key
exchange is in progress.

Previously, the read loop ran the key exchange, and writers would
block if a key exchange was going on. If a reader wrote back a packet
while processing a read packet, it could block, stopping the read
loop, thus causing a deadlock.  Such coupled read/writes are inherent
with handling requests that want a response (eg. keepalive,
opening/closing channels etc.). The buffered channels (most channels
have capacity 16) papered over these problems, but under load SSH
connections would occasionally deadlock.

Fixes #18439.

Change-Id: I7c14ff4991fa3100a5d36025125d0cf1119c471d
Reviewed-on: https://go-review.googlesource.com/35012
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>

ssh/terminal: fix line endings handling in ReadPassword

Fixes golang/go#16552

Change-Id: I18a9c9b42fe042c4871b3efb3f51bef7cca335d0
Reviewed-on: https://go-review.googlesource.com/25355
Reviewed-by: Adam Langley <alangley@gmail.com>
Reviewed-by: Adam Langley <agl@golang.org>

ssh/terminal: consume data before checking for an error.

According to the io.Reader docs, Alex had it right the first time. (See
discussion on https://golang.org/cl/25355.)

Change-Id: Ib6fb9dfb99009e034263574e82d7e9d4828df38f
Reviewed-on: https://go-review.googlesource.com/35242
TryBot-Result: Gobot Gobot <gobot@golang.org>
Run-TryBot: Adam Langley <agl@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Adam Langley <agl@golang.org>

crypto/ssh: fix parsing order for ssh.ParseDSAPrivateKey

The inline struct has the wrong order for the public and private key parts.

Change-Id: Ib3a5d6846296a2300241331a2ad398579e042ca9
Reviewed-on: https://go-review.googlesource.com/35351
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh: soft code internal channel size for testing purposes

Change-Id: I2ee0ed4ba82d2d156a7896551dea04b28cdeceb0
Reviewed-on: https://go-review.googlesource.com/35184
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>

ssh: make sure we execute the initial key exchange only once

The initial kex is started from both sides simultaneously, and before,
we could consume the the incoming kex request before we consumed from
our internal channel. This would result in initiating a key exchange
just after completing the initial one, which is not only an extra
delay, but also an error when using OpenSSH (OpenSSH does not support
key exchanges during user authentication).

Change-Id: Ia7e0748ea2bca80ae97d187bcf2931ab6422276b
Reviewed-on: https://go-review.googlesource.com/35851
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>

ssh: rationalize rekeying decisions.

1) Always force a key exchange if we exchange 2^31 packets. In the past
this might not happen if RekeyThreshold was set to a very large
interval.

2) Follow recommendations from RFC 4344 for block ciphers. For AES, we
can encrypt 2^(blocksize/4) blocks under the same keys.

On modern hardware, the previous default of 1Gb could force a key
exchange within ~10 seconds. Since the key exchange takes 3 roundtrips
(send kex init, send DH init, send NEW_KEYS), this is relatively
expensive on high-latency links.

Change-Id: I1297124a307c541b7bf22d814d136ec0c6d8ed97
Reviewed-on: https://go-review.googlesource.com/35410
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>

ssh: add debug print at the lowest level

This is a simple minded, fast print, suitable for debugging timing
sensitive issues.

Change-Id: I9ae3df5fe86f1883c1fa9265b6f7f9a98d33747e
Reviewed-on: https://go-review.googlesource.com/36054
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

ssh: reset buffered packets after sending

Since encryption messes up the packets, the wrongly retained packets
look like noise and cause application protocol errors or panics in the
SSH library.

This normally triggers very rarely: the mandatory key exchange doesn't
have parallel writes, so this failure condition would be setup on the
first key exchange, take effect only after the second key exchange.

Fortunately, the tests against openssh exercise this. This change adds
also adds a unittest.

Fixes #18850.

Change-Id: I656c8b94bfb265831daa118f4d614a2f0c65d2af
Reviewed-on: https://go-review.googlesource.com/36056
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh: Support multiple source-addresses, don't require IPv4 in tests.

The ssh tests currently require 127.0.0.1 to work which isn't
necessarily available everywhere. To fix the source-address tests,
support comma-separated source-address values per the PROTOCOL.certkeys
file:

  Comma-separated list of source addresses
  from which this certificate is accepted
  for authentication. Addresses are
  specified in CIDR format (nn.nn.nn.nn/nn
  or hhhh::hhhh/nn).
  If this option is not present then
  certificates may be presented from any
  source address.

Change-Id: I87536ff81ffa005c073da103021ebc0dfb12b620
Reviewed-on: https://go-review.googlesource.com/36110
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Heschi Kreinick <heschi@google.com>

ssh: prevent double kex at connection start, 2nd try

The previous attempt would fail in the following scenario:

* select picks "first" kex from requestKex

* read loop receives a remote kex, posts on requestKex (which is now
  empty) [*] for sending out a response, and sends pendingKex on startKex.

* select picks pendingKex from startKex, and proceeds to run the key
  exchange.

* the posting on requestKex in [*] now triggers a second key exchange.

Fixes #18861.

Change-Id: I443e82f1d04c7f17d1485fdb87072b9feec26aa8
Reviewed-on: https://go-review.googlesource.com/36055
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>

ssh/agent: fix another test to not require IPv4.

Missed a copy/paste of netPipe in change 36110.

Change-Id: I1a850dd9273d71fadc0519cf4cb2a2de6ecae4c2
Reviewed-on: https://go-review.googlesource.com/36259
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>

ssh: Add the hmac-sha2-256-etm@openssh.com algorithm

Fixes golang/go#17676

Change-Id: I96c51431b174898a6bc0f6bec7f4561d5d64819f
Reviewed-on: https://go-review.googlesource.com/35513
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh: require host key checking in the ClientConfig

This change breaks existing behavior.

Before, a missing ClientConfig.HostKeyCallback would cause host key
checking to be disabled. In this configuration, establishing a
connection to any host just works, so today, most SSH client code in
the wild does not perform any host key checks.

This makes it easy to perform a MITM attack:

* SSH installations that use keyboard-interactive or password
authentication can be attacked with MITM, thereby stealing
passwords.

* Clients that use public-key authentication with agent forwarding are
also vulnerable: the MITM server could allow the login to succeed, and
then immediately ask the agent to authenticate the login to the real
server.

* Clients that use public-key authentication without agent forwarding
are harder to attack unnoticedly: an attacker cannot authenticate the
login to the real server, so it cannot in general present a convincing
server to the victim.

Now, a missing HostKeyCallback will cause the handshake to fail. This
change also provides InsecureIgnoreHostKey() and FixedHostKey(key) as
ready made host checkers.

A simplistic parser for OpenSSH's known_hosts file is given as an
example.  This change does not provide a full-fledged parser, as it
has complexity (wildcards, revocation, hashed addresses) that will
need further consideration.

When introduced, the host checking feature maintained backward
compatibility at the expense of security. We have decided this is not
the right tradeoff for the SSH library.

Fixes golang/go#19767

Change-Id: I45fc7ba9bd1ea29c31ec23f115cdbab99913e814
Reviewed-on: https://go-review.googlesource.com/38701
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

ssh: handle error from prepareKeyChange.

Fixes #18850.

Change-Id: Id3ae89233f9e95ec3238462bf2ecda3e0c515f88
Reviewed-on: https://go-review.googlesource.com/36051
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>

ssh: fix typo in unexported comment

Thanks to Anisse Astier (@anisse) for noticing.

Change-Id: I1c282b2bb54601cf5649e194eafd5344c70331ca
Reviewed-on: https://go-review.googlesource.com/38916
Reviewed-by: dnv aps Sn <sndnvaps@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

ssh: improve client public key authentication

Previously, the public key authentication for clients would send an
enquiry to the remote for every key specified before attempting to
authenticate with the server.

Now, we immediately try to authenticate once a valid key is found.
This results in exchanging fewer packets if the valid key is near the
top of the list. If all keys fail, then the number of packets exchanged
by the client and server is unaffected.

For OpenSSH daemon, an enquiry into the validity of a key without
authentication is still recorded as an authentication attempt, so any
clients with more than MaxAuthTries public keys would not be able to
authenticate using the previous implementation. This change will allow
clients to succeed authentication if the successful key is at the start
of the list of keys.

Change-Id: I8ea42caf40c0864752218c3f6934e86b12f5b81a
Reviewed-on: https://go-review.googlesource.com/38890
Reviewed-by: Adam Langley <agl@golang.org>

ssh: reject RekeyThresholds over MaxInt64

This fixes weirdness when users use int64(-1) as sentinel value.

Also, really use cipher specific default thresholds. These were added
in a59c127441a8ae2ad9b0fb300ab36a6558bba697, but weren't taking
effect. Add a test.

Fixes golang/go#19639

Change-Id: Ie9518a0ff12fded2fca35465abb427d7a9f84340
Reviewed-on: https://go-review.googlesource.com/39431
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

ssh: fix format string in client_test.go

Change-Id: I92c3916b0b5628dc2079af82202d9bfef032c708
Reviewed-on: https://go-review.googlesource.com/39430
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>

ssh: Add support for RSA keys stored in OpenSSH's new format

Adds support for parsing RSA keys in the openssh-key-v1 private key format.

Change-Id: Iacdcbaadf72413e4067d146203604fb50b780083
Reviewed-on: https://go-review.googlesource.com/35244
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
Reviewed-by: Paul Querna <paul@querna.org>
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh: support forwarding of Unix domain socket connections

This commit implements OpenSSH streamlocal extension, providing the equivalent
of `ssh -L local.sock:remote.sock`.

Change-Id: Idd6287d5a5669c643132bba770c3b4194615e84d
Reviewed-on: https://go-review.googlesource.com/38614
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh: support MaxAuthTries on ServerConfig

This change breaks backwards compatibility.

MaxAuthTries specifies the maximum number of authentication attempts
permitted per connection. If set to a negative number, the server will
allow unlimited authentication attempts. MaxAuthTries defaults to 6 if
not specified, which is a backwards incompatible change. On exceeding
maximum authentication attempts, the server will send a disconnect
message to the client.

This configuration property mirrors a similar property in sshd_config
and prevents bad actors from continuously trying authentication.

Change-Id: Ic77d2c29ee2fd2ae5c764becf7df91d29d03131b
Reviewed-on: https://go-review.googlesource.com/35230
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh: set rekeying thresholds on construction

The normal handshake kicks off with a waitSession(), which guarantees
that we never attempt to send data before the first kex is completed,
but ensuring readPacketsLeft > 0 and writePacketsLeft > 0 helps
understand that thresholds can never cause spurious rekeying at the
start of a connection.

Change-Id: If5bcafcda0c7d16fd21f22c664101ac5f5b487d7
Reviewed-on: https://go-review.googlesource.com/38696
Reviewed-by: Adam Langley <agl@golang.org>
Run-TryBot: Adam Langley <agl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh: fix reset{Read,Write}Thresholds for initial setup

Fixes a nil pointer dereference that slipped through buildbots because
it was introduced by the last two commits.

Change-Id: Ib269e910956cd8b3b46e217b03fde1b61572260a
Reviewed-on: https://go-review.googlesource.com/40530
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh/knownhosts: a parser for the OpenSSH known_hosts file format

Change-Id: I271c90ff3a6d59e2e075c785a6bdb79e4b0849fa
Reviewed-on: https://go-review.googlesource.com/40354
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>

ssh/knownhosts: fix variable reuse bug in checkAddrs

Consider the following code:
	var p *int
	a := []int{0, 1, 2, 3}
	for _, i := range a {
		if i == 1 {
			p = &i
		}
	}
	fmt.Println(*p) // Prints 3

This prints 3 because the variable i is the exact same variable across
all iterations of the loop. When the address is taken for some specific
iteration, the user's intent is to capture the value of i at that
given loop, but instead the value of i in the last loop is what remains.

A bug this sort occurs in the check logic since the address of the
knownKey is taken, but is changed upon subsequent iterations of the
loop (which happens when there are multiple lines).

Change-Id: Ic626778cdcde3968dcff4fa5e7206274957dcb04
Reviewed-on: https://go-review.googlesource.com/40937
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh/knownhosts: support hashed hostnames

Change-Id: I855a6542a2eb2ae1d223f03892c0f19da81a4f8d
Reviewed-on: https://go-review.googlesource.com/40532
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>

ssh/knownhosts: add file + linenumber for parse errors

Change-Id: Iddcb145ecd8a6b51c72ad3d77b242975baf4a5cf
Reviewed-on: https://go-review.googlesource.com/41210
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Sam Whited <sam@samwhited.com>
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>

ssh/terminal: implement missing functions for Solaris/OmniOS

    terminal.MakeRaw
    terminal.Restore
    terminal.GetState
    terminal.GetSize

Fixes golang/go#20062

Change-Id: I9ccf194215998c5b80dbedc4f248b481f0ca57a6
Reviewed-on: https://go-review.googlesource.com/41297
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

ssh/knownhosts: add IsHostAuthority.

This is a breaking change.

This adds a new hostkey callback which takes the hostname field
restrictions into account when validating host certificates.

Prior to this, a known_hosts file with the following entry

  @cert-authority *.example.com ssh-rsa <example.com public key>

would, when passed to knownhosts.New() generate an ssh.HostKeyCallback
that would accept all host certificates signed by the example.com public
key, no matter what host the client was connecting to.

After this change, that known_hosts entry can only be used to validate
host certificates presented when connecting to hosts under *.example.com

This also renames IsAuthority to IsUserAuthority to make its intended
purpose more clear.

Change-Id: I7188a53fdd40a8c0bc21983105317b3498f567bb
Reviewed-on: https://go-review.googlesource.com/41751
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh/knownhosts: test coverage for IsHostAuthority

Change-Id: Iad24fed7cec998e02620ec0eb61658786156ba41
Reviewed-on: https://go-review.googlesource.com/42530
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

crypto/ssh: fix tests on Go 1.7 on OpenBSD and Windows

Dialing the 0.0.0.0 address (as returned by net.Addr().String() for a
net.Listen("tcp", ":1") address) is not yet guaranteed to work. It's
currently OS-dependent.

For some reason it works on Go 1.8+, but it hasn't yet been defined to
work reliably.

Fix the tests for now (since we need to support older Go releases),
even if this might work in the future.

Updates golang/go#18806

Change-Id: I2f0476b1d4f2673ab64ffedfa733f2d92fceb6ff
Reviewed-on: https://go-review.googlesource.com/42496
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>

ssh: change the local copy of the ServerConfig passed to NewServerConn

Otherwise callers are forced to serialize access to the ServerConfig.

Change-Id: Id36f4d2877ea28b18447ef777d3839b21136c22f
Reviewed-on: https://go-review.googlesource.com/42821
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

x/crypto/ssh: fix host certificate principal evaluation to check for hostname only

SSH host certificates are expected to contain hostnames only,
not "host:port" format.

This change allows Go clients to connect to OpenSSH servers that
use host certificates.

Note, this change will break any clients that use ssh.NewClientConn()
with an `addr` that is not in `host:port` format (they will see a
"missing port in address" error).

Fixes bug 20273.

Change-Id: I5a306c6b7b419a737e1f0f9c5ca8c585e21a45a4
Reviewed-on: https://go-review.googlesource.com/43475
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

ssh: fixing a small typo in connection.go

Change-Id: Iffbed7e16a8bb32c5ff7c393f3b6ad7dcffc69ac
Reviewed-on: https://go-review.googlesource.com/44340
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>

ssh: add ParsePrivateKeysWithPassphrase

ssh package doesn't provide way to parse private keys with passphrase.

Fixes golang/go#18692

Change-Id: Ic139f11b6dfe7ef61690d6125e0673d50a48db16
Reviewed-on: https://go-review.googlesource.com/36079
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Han-Wen Nienhuys <hanwen@google.com>

ssh: clarify intended use of Permissions.

The Permissions struct should be used to pass information from
authentication callback to server application.

Fixes golang/go#20094.

Change-Id: I5542b657d053452327260707a24925286546bfdd
Reviewed-on: https://go-review.googlesource.com/45311
Run-TryBot: Han-Wen Nienhuys <hanwen@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

all: gofmt ./...

Change-Id: I8ffee4dc712091e424b83a9f5a3cc2a6724abefc
Reviewed-on: https://go-review.googlesource.com/46050
Reviewed-by: Matt Layher <mdlayher@gmail.com>
This commit is contained in:
Boshi Lian 2016-10-09 00:56:47 -07:00
parent 2392a6b13f
commit 76f411272b
46 changed files with 3316 additions and 786 deletions
Download patch file Download diff file Expand all files Collapse all files

1
.golangssh_lastpick Normal file
View file

@ -0,0 +1 @@
abc3c1b02083efdbef727c8631a865ad7d8d8b19

12
pick_golangssh.sh Executable file
View file

@ -0,0 +1,12 @@
#!/bin/bash
set -e
VER_FILE=".golangssh_lastpick"
LAST_VER=`cat $VER_FILE`
git fetch https://github.com/golang/crypto.git
for v in `git log --reverse --format=%H $LAST_VER..FETCH_HEAD ssh`; do
git cherry-pick $v
echo $v > $VER_FILE
done

15
ssh/agent/client_test.go
View file

@ -182,7 +182,10 @@ func TestCert(t *testing.T) {
func netPipe() (net.Conn, net.Conn, error) {
listener, err := net.Listen("tcp", "127.0.0.1:0")
if err != nil {
return nil, nil, err
listener, err = net.Listen("tcp", "[::1]:0")
if err != nil {
return nil, nil, err
}
}
defer listener.Close()
c1, err := net.Dial("tcp", listener.Addr().String())
@ -200,6 +203,9 @@ func netPipe() (net.Conn, net.Conn, error) {
}
func TestAuth(t *testing.T) {
agent, _, cleanup := startAgent(t)
defer cleanup()
a, b, err := netPipe()
if err != nil {
t.Fatalf("netPipe: %v", err)
@ -208,9 +214,6 @@ func TestAuth(t *testing.T) {
defer a.Close()
defer b.Close()
agent, _, cleanup := startAgent(t)
defer cleanup()
if err := agent.Add(AddedKey{PrivateKey: testPrivateKeys["rsa"], Comment: "comment"}); err != nil {
t.Errorf("Add: %v", err)
}
@ -233,7 +236,9 @@ func TestAuth(t *testing.T) {
conn.Close()
}()
conf := ssh.ClientConfig{}
conf := ssh.ClientConfig{
HostKeyCallback: ssh.InsecureIgnoreHostKey(),
}
conf.Auth = append(conf.Auth, ssh.PublicKeysCallback(agent.Signers))
conn, _, _, err := ssh.NewClientConn(b, "", &conf)
if err != nil {

15
ssh/agent/example_test.go
View file

@ -6,20 +6,20 @@ package agent_test
import (
"log"
"os"
"net"
"os"
"golang.org/x/crypto/ssh"
"golang.org/x/crypto/ssh/agent"
"golang.org/x/crypto/ssh"
"golang.org/x/crypto/ssh/agent"
)
func ExampleClientAgent() {
// ssh-agent has a UNIX socket under $SSH_AUTH_SOCK
socket := os.Getenv("SSH_AUTH_SOCK")
conn, err := net.Dial("unix", socket)
if err != nil {
log.Fatalf("net.Dial: %v", err)
}
conn, err := net.Dial("unix", socket)
if err != nil {
log.Fatalf("net.Dial: %v", err)
}
agentClient := agent.NewClient(conn)
config := &ssh.ClientConfig{
User: "username",
@ -29,6 +29,7 @@ func ExampleClientAgent() {
// wants it.
ssh.PublicKeysCallback(agentClient.Signers),
},
HostKeyCallback: ssh.InsecureIgnoreHostKey(),
}
sshc, err := ssh.Dial("tcp", "localhost:22", config)

4
ssh/agent/server_test.go
View file

@ -56,7 +56,9 @@ func TestSetupForwardAgent(t *testing.T) {
incoming <- conn
}()
conf := ssh.ClientConfig{}
conf := ssh.ClientConfig{
HostKeyCallback: ssh.InsecureIgnoreHostKey(),
}
conn, chans, reqs, err := ssh.NewClientConn(b, "", &conf)
if err != nil {
t.Fatalf("NewClientConn: %v", err)

36
ssh/certs.go
View file

@ -251,10 +251,18 @@ type CertChecker struct {
// for user certificates.
SupportedCriticalOptions []string
// IsAuthority should return true if the key is recognized as
// an authority. This allows for certificates to be signed by other
// certificates.
IsAuthority func(auth PublicKey) bool
// IsUserAuthority should return true if the key is recognized as an
// authority for the given user certificate. This allows for
// certificates to be signed by other certificates. This must be set
// if this CertChecker will be checking user certificates.
IsUserAuthority func(auth PublicKey) bool
// IsHostAuthority should report whether the key is recognized as
// an authority for this host. This allows for certificates to be
// signed by other keys, and for those other keys to only be valid
// signers for particular hostnames. This must be set if this
// CertChecker will be checking host certificates.
IsHostAuthority func(auth PublicKey, address string) bool
// Clock is used for verifying time stamps. If nil, time.Now
// is used.
@ -268,7 +276,7 @@ type CertChecker struct {
// HostKeyFallback is called when CertChecker.CheckHostKey encounters a
// public key that is not a certificate. It must implement host key
// validation or else, if nil, all such keys are rejected.
HostKeyFallback func(addr string, remote net.Addr, key PublicKey) error
HostKeyFallback HostKeyCallback
// IsRevoked is called for each certificate so that revocation checking
// can be implemented. It should return true if the given certificate
@ -290,8 +298,17 @@ func (c *CertChecker) CheckHostKey(addr string, remote net.Addr, key PublicKey)
if cert.CertType != HostCert {
return fmt.Errorf("ssh: certificate presented as a host key has type %d", cert.CertType)
}
if !c.IsHostAuthority(cert.SignatureKey, addr) {
return fmt.Errorf("ssh: no authorities for hostname: %v", addr)
}
return c.CheckCert(addr, cert)
hostname, _, err := net.SplitHostPort(addr)
if err != nil {
return err
}
// Pass hostname only as principal for host certificates (consistent with OpenSSH)
return c.CheckCert(hostname, cert)
}
// Authenticate checks a user certificate. Authenticate can be used as
@ -308,6 +325,9 @@ func (c *CertChecker) Authenticate(conn ConnMetadata, pubKey PublicKey) (*Permis
if cert.CertType != UserCert {
return nil, fmt.Errorf("ssh: cert has type %d", cert.CertType)
}
if !c.IsUserAuthority(cert.SignatureKey) {
return nil, fmt.Errorf("ssh: certificate signed by unrecognized authority")
}
if err := c.CheckCert(conn.User(), cert); err != nil {
return nil, err
@ -356,10 +376,6 @@ func (c *CertChecker) CheckCert(principal string, cert *Certificate) error {
}
}
if !c.IsAuthority(cert.SignatureKey) {
return fmt.Errorf("ssh: certificate signed by unrecognized authority")
}
clock := c.Clock
if clock == nil {
clock = time.Now

30
ssh/certs_test.go
View file

@ -104,7 +104,7 @@ func TestValidateCert(t *testing.T) {
t.Fatalf("got %v (%T), want *Certificate", key, key)
}
checker := CertChecker{}
checker.IsAuthority = func(k PublicKey) bool {
checker.IsUserAuthority = func(k PublicKey) bool {
return bytes.Equal(k.Marshal(), validCert.SignatureKey.Marshal())
}
@ -142,7 +142,7 @@ func TestValidateCertTime(t *testing.T) {
checker := CertChecker{
Clock: func() time.Time { return time.Unix(ts, 0) },
}
checker.IsAuthority = func(k PublicKey) bool {
checker.IsUserAuthority = func(k PublicKey) bool {
return bytes.Equal(k.Marshal(),
testPublicKeys["ecdsa"].Marshal())
}
@ -160,7 +160,7 @@ func TestValidateCertTime(t *testing.T) {
func TestHostKeyCert(t *testing.T) {
cert := &Certificate{
ValidPrincipals: []string{"hostname", "hostname.domain"},
ValidPrincipals: []string{"hostname", "hostname.domain", "otherhost"},
Key: testPublicKeys["rsa"],
ValidBefore: CertTimeInfinity,
CertType: HostCert,
@ -168,8 +168,8 @@ func TestHostKeyCert(t *testing.T) {
cert.SignCert(rand.Reader, testSigners["ecdsa"])
checker := &CertChecker{
IsAuthority: func(p PublicKey) bool {
return bytes.Equal(testPublicKeys["ecdsa"].Marshal(), p.Marshal())
IsHostAuthority: func(p PublicKey, addr string) bool {
return addr == "hostname:22" && bytes.Equal(testPublicKeys["ecdsa"].Marshal(), p.Marshal())
},
}
@ -178,7 +178,14 @@ func TestHostKeyCert(t *testing.T) {
t.Errorf("NewCertSigner: %v", err)
}
for _, name := range []string{"hostname", "otherhost"} {
for _, test := range []struct {
addr string
succeed bool
}{
{addr: "hostname:22", succeed: true},
{addr: "otherhost:22", succeed: false}, // The certificate is valid for 'otherhost' as hostname, but we only recognize the authority of the signer for the address 'hostname:22'
{addr: "lasthost:22", succeed: false},
} {
c1, c2, err := netPipe()
if err != nil {
t.Fatalf("netPipe: %v", err)
@ -201,16 +208,15 @@ func TestHostKeyCert(t *testing.T) {
User: "user",
HostKeyCallback: checker.CheckHostKey,
}
_, _, _, err = NewClientConn(c2, name, config)
_, _, _, err = NewClientConn(c2, test.addr, config)
succeed := name == "hostname"
if (err == nil) != succeed {
t.Fatalf("NewClientConn(%q): %v", name, err)
if (err == nil) != test.succeed {
t.Fatalf("NewClientConn(%q): %v", test.addr, err)
}
err = <-errc
if (err == nil) != succeed {
t.Fatalf("NewServerConn(%q): %v", name, err)
if (err == nil) != test.succeed {
t.Fatalf("NewServerConn(%q): %v", test.addr, err)
}
}
}

4
ssh/channel.go
View file

@ -461,8 +461,8 @@ func (m *mux) newChannel(chanType string, direction channelDirection, extraData
pending: newBuffer(),
extPending: newBuffer(),
direction: direction,
incomingRequests: make(chan *Request, 16),
msg: make(chan interface{}, 16),
incomingRequests: make(chan *Request, chanSize),
msg: make(chan interface{}, chanSize),
chanType: chanType,
extraData: extraData,
mux: m,

64
ssh/cipher.go
View file

@ -135,6 +135,7 @@ const prefixLen = 5
type streamPacketCipher struct {
mac hash.Hash
cipher cipher.Stream
etm bool
// The following members are to avoid per-packet allocations.
prefix [prefixLen]byte
@ -150,7 +151,14 @@ func (s *streamPacketCipher) readPacket(seqNum uint32, r io.Reader) ([]byte, err
return nil, err
}
s.cipher.XORKeyStream(s.prefix[:], s.prefix[:])
var encryptedPaddingLength [1]byte
if s.mac != nil && s.etm {
copy(encryptedPaddingLength[:], s.prefix[4:5])
s.cipher.XORKeyStream(s.prefix[4:5], s.prefix[4:5])
} else {
s.cipher.XORKeyStream(s.prefix[:], s.prefix[:])
}
length := binary.BigEndian.Uint32(s.prefix[0:4])
paddingLength := uint32(s.prefix[4])
@ -159,7 +167,12 @@ func (s *streamPacketCipher) readPacket(seqNum uint32, r io.Reader) ([]byte, err
s.mac.Reset()
binary.BigEndian.PutUint32(s.seqNumBytes[:], seqNum)
s.mac.Write(s.seqNumBytes[:])
s.mac.Write(s.prefix[:])
if s.etm {
s.mac.Write(s.prefix[:4])
s.mac.Write(encryptedPaddingLength[:])
} else {
s.mac.Write(s.prefix[:])
}
macSize = uint32(s.mac.Size())
}
@ -184,10 +197,17 @@ func (s *streamPacketCipher) readPacket(seqNum uint32, r io.Reader) ([]byte, err
}
mac := s.packetData[length-1:]
data := s.packetData[:length-1]
if s.mac != nil && s.etm {
s.mac.Write(data)
}
s.cipher.XORKeyStream(data, data)
if s.mac != nil {
s.mac.Write(data)
if !s.etm {
s.mac.Write(data)
}
s.macResult = s.mac.Sum(s.macResult[:0])
if subtle.ConstantTimeCompare(s.macResult, mac) != 1 {
return nil, errors.New("ssh: MAC failure")
@ -203,7 +223,13 @@ func (s *streamPacketCipher) writePacket(seqNum uint32, w io.Writer, rand io.Rea
return errors.New("ssh: packet too large")
}
paddingLength := packetSizeMultiple - (prefixLen+len(packet))%packetSizeMultiple
aadlen := 0
if s.mac != nil && s.etm {
// packet length is not encrypted for EtM modes
aadlen = 4
}
paddingLength := packetSizeMultiple - (prefixLen+len(packet)-aadlen)%packetSizeMultiple
if paddingLength < 4 {
paddingLength += packetSizeMultiple
}
@ -220,15 +246,37 @@ func (s *streamPacketCipher) writePacket(seqNum uint32, w io.Writer, rand io.Rea
s.mac.Reset()
binary.BigEndian.PutUint32(s.seqNumBytes[:], seqNum)
s.mac.Write(s.seqNumBytes[:])
if s.etm {
// For EtM algorithms, the packet length must stay unencrypted,
// but the following data (padding length) must be encrypted
s.cipher.XORKeyStream(s.prefix[4:5], s.prefix[4:5])
}
s.mac.Write(s.prefix[:])
if !s.etm {
// For non-EtM algorithms, the algorithm is applied on unencrypted data
s.mac.Write(packet)
s.mac.Write(padding)
}
}
if !(s.mac != nil && s.etm) {
// For EtM algorithms, the padding length has already been encrypted
// and the packet length must remain unencrypted
s.cipher.XORKeyStream(s.prefix[:], s.prefix[:])
}
s.cipher.XORKeyStream(packet, packet)
s.cipher.XORKeyStream(padding, padding)
if s.mac != nil && s.etm {
// For EtM algorithms, packet and padding must be encrypted
s.mac.Write(packet)
s.mac.Write(padding)
}
s.cipher.XORKeyStream(s.prefix[:], s.prefix[:])
s.cipher.XORKeyStream(packet, packet)
s.cipher.XORKeyStream(padding, padding)
if _, err := w.Write(s.prefix[:]); err != nil {
return err
}

62
ssh/cipher_test.go
View file

@ -26,39 +26,41 @@ func TestPacketCiphers(t *testing.T) {
defer delete(cipherModes, aes128cbcID)
for cipher := range cipherModes {
kr := &kexResult{Hash: crypto.SHA1}
algs := directionAlgorithms{
Cipher: cipher,
MAC: "hmac-sha1",
Compression: "none",
}
client, err := newPacketCipher(clientKeys, algs, kr)
if err != nil {
t.Errorf("newPacketCipher(client, %q): %v", cipher, err)
continue
}
server, err := newPacketCipher(clientKeys, algs, kr)
if err != nil {
t.Errorf("newPacketCipher(client, %q): %v", cipher, err)
continue
}
for mac := range macModes {
kr := &kexResult{Hash: crypto.SHA1}
algs := directionAlgorithms{
Cipher: cipher,
MAC: mac,
Compression: "none",
}
client, err := newPacketCipher(clientKeys, algs, kr)
if err != nil {
t.Errorf("newPacketCipher(client, %q, %q): %v", cipher, mac, err)
continue
}
server, err := newPacketCipher(clientKeys, algs, kr)
if err != nil {
t.Errorf("newPacketCipher(client, %q, %q): %v", cipher, mac, err)
continue
}
want := "bla bla"
input := []byte(want)
buf := &bytes.Buffer{}
if err := client.writePacket(0, buf, rand.Reader, input); err != nil {
t.Errorf("writePacket(%q): %v", cipher, err)
continue
}
want := "bla bla"
input := []byte(want)
buf := &bytes.Buffer{}
if err := client.writePacket(0, buf, rand.Reader, input); err != nil {
t.Errorf("writePacket(%q, %q): %v", cipher, mac, err)
continue
}
packet, err := server.readPacket(0, buf)
if err != nil {
t.Errorf("readPacket(%q): %v", cipher, err)
continue
}
packet, err := server.readPacket(0, buf)
if err != nil {
t.Errorf("readPacket(%q, %q): %v", cipher, mac, err)
continue
}
if string(packet) != want {
t.Errorf("roundtrip(%q): got %q, want %q", cipher, packet, want)
if string(packet) != want {
t.Errorf("roundtrip(%q, %q): got %q, want %q", cipher, mac, packet, want)
}
}
}
}

62
ssh/client.go
View file

@ -5,6 +5,7 @@
package ssh
import (
"bytes"
"errors"
"fmt"
"net"
@ -13,7 +14,7 @@ import (
)
// Client implements a traditional SSH client that supports shells,
// subprocesses, port forwarding and tunneled dialing.
// subprocesses, TCP port/streamlocal forwarding and tunneled dialing.
type Client struct {
Conn
@ -40,7 +41,7 @@ func (c *Client) HandleChannelOpen(channelType string) <-chan NewChannel {
return nil
}
ch = make(chan NewChannel, 16)
ch = make(chan NewChannel, chanSize)
c.channelHandlers[channelType] = ch
return ch
}
@ -59,6 +60,7 @@ func NewClient(c Conn, chans <-chan NewChannel, reqs <-chan *Request) *Client {
conn.forwards.closeAll()
}()
go conn.forwards.handleChannels(conn.HandleChannelOpen("forwarded-tcpip"))
go conn.forwards.handleChannels(conn.HandleChannelOpen("forwarded-streamlocal@openssh.com"))
return conn
}
@ -68,6 +70,11 @@ func NewClient(c Conn, chans <-chan NewChannel, reqs <-chan *Request) *Client {
func NewClientConn(c net.Conn, addr string, config *ClientConfig) (Conn, <-chan NewChannel, <-chan *Request, error) {
fullConf := *config
fullConf.SetDefaults()
if fullConf.HostKeyCallback == nil {
c.Close()
return nil, nil, nil, errors.New("ssh: must specify HostKeyCallback")
}
conn := &connection{
sshConn: sshConn{conn: c},
}
@ -97,13 +104,11 @@ func (c *connection) clientHandshake(dialAddress string, config *ClientConfig) e
c.transport = newClientTransport(
newTransport(c.sshConn.conn, config.Rand, true /* is client */),
c.clientVersion, c.serverVersion, config, dialAddress, c.sshConn.RemoteAddr())
if err := c.transport.requestInitialKeyChange(); err != nil {
if err := c.transport.waitSession(); err != nil {
return err
}
// We just did the key change, so the session ID is established.
c.sessionID = c.transport.getSessionID()
return c.clientAuthenticate(config)
}
@ -175,6 +180,13 @@ func Dial(network, addr string, config *ClientConfig) (*Client, error) {
return NewClient(c, chans, reqs), nil
}
// HostKeyCallback is the function type used for verifying server
// keys. A HostKeyCallback must return nil if the host key is OK, or
// an error to reject it. It receives the hostname as passed to Dial
// or NewClientConn. The remote address is the RemoteAddr of the
// net.Conn underlying the the SSH connection.
type HostKeyCallback func(hostname string, remote net.Addr, key PublicKey) error
// A ClientConfig structure is used to configure a Client. It must not be
// modified after having been passed to an SSH function.
type ClientConfig struct {
@ -190,10 +202,12 @@ type ClientConfig struct {
// be used during authentication.
Auth []AuthMethod
// HostKeyCallback, if not nil, is called during the cryptographic
// handshake to validate the server's host key. A nil HostKeyCallback
// implies that all host keys are accepted.
HostKeyCallback func(hostname string, remote net.Addr, key PublicKey) error
// HostKeyCallback is called during the cryptographic
// handshake to validate the server's host key. The client
// configuration must supply this callback for the connection
// to succeed. The functions InsecureIgnoreHostKey or
// FixedHostKey can be used for simplistic host key checks.
HostKeyCallback HostKeyCallback
// ClientVersion contains the version identification string that will
// be used for the connection. If empty, a reasonable default is used.
@ -211,3 +225,33 @@ type ClientConfig struct {
// A Timeout of zero means no timeout.
Timeout time.Duration
}
// InsecureIgnoreHostKey returns a function that can be used for
// ClientConfig.HostKeyCallback to accept any host key. It should
// not be used for production code.
func InsecureIgnoreHostKey() HostKeyCallback {
return func(hostname string, remote net.Addr, key PublicKey) error {
return nil
}
}
type fixedHostKey struct {
key PublicKey
}
func (f *fixedHostKey) check(hostname string, remote net.Addr, key PublicKey) error {
if f.key == nil {
return fmt.Errorf("ssh: required host key was nil")
}
if !bytes.Equal(key.Marshal(), f.key.Marshal()) {
return fmt.Errorf("ssh: host key mismatch")
}
return nil
}
// FixedHostKey returns a function for use in
// ClientConfig.HostKeyCallback to accept only a specific host key.
func FixedHostKey(key PublicKey) HostKeyCallback {
hk := &fixedHostKey{key}
return hk.check
}

53
ssh/client_auth.go
View file

@ -30,8 +30,10 @@ func (c *connection) clientAuthenticate(config *ClientConfig) error {
// then any untried methods suggested by the server.
tried := make(map[string]bool)
var lastMethods []string
sessionID := c.transport.getSessionID()
for auth := AuthMethod(new(noneAuth)); auth != nil; {
ok, methods, err := auth.auth(c.transport.getSessionID(), config.User, c.transport, config.Rand)
ok, methods, err := auth.auth(sessionID, config.User, c.transport, config.Rand)
if err != nil {
return err
}
@ -177,31 +179,26 @@ func (cb publicKeyCallback) method() string {
}
func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand io.Reader) (bool, []string, error) {
// Authentication is performed in two stages. The first stage sends an
// enquiry to test if each key is acceptable to the remote. The second
// stage attempts to authenticate with the valid keys obtained in the
// first stage.
// Authentication is performed by sending an enquiry to test if a key is
// acceptable to the remote. If the key is acceptable, the client will
// attempt to authenticate with the valid key. If not the client will repeat
// the process with the remaining keys.
signers, err := cb()
if err != nil {
return false, nil, err
}
var validKeys []Signer
for _, signer := range signers {
if ok, err := validateKey(signer.PublicKey(), user, c); ok {
validKeys = append(validKeys, signer)
} else {
if err != nil {
return false, nil, err
}
}
}
// methods that may continue if this auth is not successful.
var methods []string
for _, signer := range validKeys {
pub := signer.PublicKey()
for _, signer := range signers {
ok, err := validateKey(signer.PublicKey(), user, c)
if err != nil {
return false, nil, err
}
if !ok {
continue
}
pub := signer.PublicKey()
pubKey := pub.Marshal()
sign, err := signer.Sign(rand, buildDataSignedForAuth(session, userAuthRequestMsg{
User: user,
@ -234,13 +231,29 @@ func (cb publicKeyCallback) auth(session []byte, user string, c packetConn, rand
if err != nil {
return false, nil, err
}
if success {
// If authentication succeeds or the list of available methods does not
// contain the "publickey" method, do not attempt to authenticate with any
// other keys. According to RFC 4252 Section 7, the latter can occur when
// additional authentication methods are required.
if success || !containsMethod(methods, cb.method()) {
return success, methods, err
}
}
return false, methods, nil
}
func containsMethod(methods []string, method string) bool {
for _, m := range methods {
if m == method {
return true
}
}
return false
}
// validateKey validates the key provided is acceptable to the server.
func validateKey(key PublicKey, user string, c packetConn) (bool, error) {
pubKey := key.Marshal()

147
ssh/client_auth_test.go
View file

@ -38,7 +38,7 @@ func tryAuth(t *testing.T, config *ClientConfig) error {
defer c2.Close()
certChecker := CertChecker{
IsAuthority: func(k PublicKey) bool {
IsUserAuthority: func(k PublicKey) bool {
return bytes.Equal(k.Marshal(), testPublicKeys["ecdsa"].Marshal())
},
UserKeyFallback: func(conn ConnMetadata, key PublicKey) (*Permissions, error) {
@ -76,9 +76,6 @@ func tryAuth(t *testing.T, config *ClientConfig) error {
}
return nil, errors.New("keyboard-interactive failed")
},
AuthLogCallback: func(conn ConnMetadata, method string, err error) {
t.Logf("user %q, method %q: %v", conn.User(), method, err)
},
}
serverConfig.AddHostKey(testSigners["rsa"])
@ -93,6 +90,7 @@ func TestClientAuthPublicKey(t *testing.T) {
Auth: []AuthMethod{
PublicKeys(testSigners["rsa"]),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, config); err != nil {
t.Fatalf("unable to dial remote side: %s", err)
@ -105,6 +103,7 @@ func TestAuthMethodPassword(t *testing.T) {
Auth: []AuthMethod{
Password(clientPassword),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, config); err != nil {
@ -124,6 +123,7 @@ func TestAuthMethodFallback(t *testing.T) {
return "WRONG", nil
}),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, config); err != nil {
@ -142,6 +142,7 @@ func TestAuthMethodWrongPassword(t *testing.T) {
Password("wrong"),
PublicKeys(testSigners["rsa"]),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, config); err != nil {
@ -159,6 +160,7 @@ func TestAuthMethodKeyboardInteractive(t *testing.T) {
Auth: []AuthMethod{
KeyboardInteractive(answers.Challenge),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, config); err != nil {
@ -204,6 +206,7 @@ func TestAuthMethodRSAandDSA(t *testing.T) {
Auth: []AuthMethod{
PublicKeys(testSigners["dsa"], testSigners["rsa"]),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, config); err != nil {
t.Fatalf("client could not authenticate with rsa key: %v", err)
@ -220,6 +223,7 @@ func TestClientHMAC(t *testing.T) {
Config: Config{
MACs: []string{mac},
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, config); err != nil {
t.Fatalf("client could not authenticate with mac algo %s: %v", mac, err)
@ -255,6 +259,7 @@ func TestClientUnsupportedKex(t *testing.T) {
Config: Config{
KeyExchanges: []string{"diffie-hellman-group-exchange-sha256"}, // not currently supported
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, config); err == nil || !strings.Contains(err.Error(), "common algorithm") {
t.Errorf("got %v, expected 'common algorithm'", err)
@ -274,22 +279,23 @@ func TestClientLoginCert(t *testing.T) {
}
clientConfig := &ClientConfig{
User: "user",
User: "user",
HostKeyCallback: InsecureIgnoreHostKey(),
}
clientConfig.Auth = append(clientConfig.Auth, PublicKeys(certSigner))
t.Log("should succeed")
// should succeed
if err := tryAuth(t, clientConfig); err != nil {
t.Errorf("cert login failed: %v", err)
}
t.Log("corrupted signature")
// corrupted signature
cert.Signature.Blob[0]++
if err := tryAuth(t, clientConfig); err == nil {
t.Errorf("cert login passed with corrupted sig")
}
t.Log("revoked")
// revoked
cert.Serial = 666
cert.SignCert(rand.Reader, testSigners["ecdsa"])
if err := tryAuth(t, clientConfig); err == nil {
@ -297,13 +303,13 @@ func TestClientLoginCert(t *testing.T) {
}
cert.Serial = 1
t.Log("sign with wrong key")
// sign with wrong key
cert.SignCert(rand.Reader, testSigners["dsa"])
if err := tryAuth(t, clientConfig); err == nil {
t.Errorf("cert login passed with non-authoritative key")
}
t.Log("host cert")
// host cert
cert.CertType = HostCert
cert.SignCert(rand.Reader, testSigners["ecdsa"])
if err := tryAuth(t, clientConfig); err == nil {
@ -311,14 +317,14 @@ func TestClientLoginCert(t *testing.T) {
}
cert.CertType = UserCert
t.Log("principal specified")
// principal specified
cert.ValidPrincipals = []string{"user"}
cert.SignCert(rand.Reader, testSigners["ecdsa"])
if err := tryAuth(t, clientConfig); err != nil {
t.Errorf("cert login failed: %v", err)
}
t.Log("wrong principal specified")
// wrong principal specified
cert.ValidPrincipals = []string{"fred"}
cert.SignCert(rand.Reader, testSigners["ecdsa"])
if err := tryAuth(t, clientConfig); err == nil {
@ -326,22 +332,22 @@ func TestClientLoginCert(t *testing.T) {
}
cert.ValidPrincipals = nil
t.Log("added critical option")
// added critical option
cert.CriticalOptions = map[string]string{"root-access": "yes"}
cert.SignCert(rand.Reader, testSigners["ecdsa"])
if err := tryAuth(t, clientConfig); err == nil {
t.Errorf("cert login passed with unrecognized critical option")
}
t.Log("allowed source address")
cert.CriticalOptions = map[string]string{"source-address": "127.0.0.42/24"}
// allowed source address
cert.CriticalOptions = map[string]string{"source-address": "127.0.0.42/24,::42/120"}
cert.SignCert(rand.Reader, testSigners["ecdsa"])
if err := tryAuth(t, clientConfig); err != nil {
t.Errorf("cert login with source-address failed: %v", err)
}
t.Log("disallowed source address")
cert.CriticalOptions = map[string]string{"source-address": "127.0.0.42"}
// disallowed source address
cert.CriticalOptions = map[string]string{"source-address": "127.0.0.42,::42"}
cert.SignCert(rand.Reader, testSigners["ecdsa"])
if err := tryAuth(t, clientConfig); err == nil {
t.Errorf("cert login with source-address succeeded")
@ -364,6 +370,7 @@ func testPermissionsPassing(withPermissions bool, t *testing.T) {
Auth: []AuthMethod{
PublicKeys(testSigners["rsa"]),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if withPermissions {
clientConfig.User = "permissions"
@ -410,6 +417,7 @@ func TestRetryableAuth(t *testing.T) {
}), 2),
PublicKeys(testSigners["rsa"]),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, config); err != nil {
@ -431,7 +439,8 @@ func ExampleRetryableAuthMethod(t *testing.T) {
}
config := &ClientConfig{
User: user,
HostKeyCallback: InsecureIgnoreHostKey(),
User: user,
Auth: []AuthMethod{
RetryableAuthMethod(KeyboardInteractiveChallenge(Cb), NumberOfPrompts),
},
@ -451,7 +460,8 @@ func TestClientAuthNone(t *testing.T) {
serverConfig.AddHostKey(testSigners["rsa"])
clientConfig := &ClientConfig{
User: user,
User: user,
HostKeyCallback: InsecureIgnoreHostKey(),
}
c1, c2, err := netPipe()
@ -464,9 +474,106 @@ func TestClientAuthNone(t *testing.T) {
go NewClientConn(c2, "", clientConfig)
serverConn, err := newServer(c1, serverConfig)
if err != nil {
t.Fatal("newServer: %v", err)
t.Fatalf("newServer: %v", err)
}
if serverConn.User() != user {
t.Fatalf("server: got %q, want %q", serverConn.User(), user)
}
}
// Test if authentication attempts are limited on server when MaxAuthTries is set
func TestClientAuthMaxAuthTries(t *testing.T) {
user := "testuser"
serverConfig := &ServerConfig{
MaxAuthTries: 2,
PasswordCallback: func(conn ConnMetadata, pass []byte) (*Permissions, error) {
if conn.User() == "testuser" && string(pass) == "right" {
return nil, nil
}
return nil, errors.New("password auth failed")
},
}
serverConfig.AddHostKey(testSigners["rsa"])
expectedErr := fmt.Errorf("ssh: handshake failed: %v", &disconnectMsg{
Reason: 2,
Message: "too many authentication failures",
})
for tries := 2; tries < 4; tries++ {
n := tries
clientConfig := &ClientConfig{
User: user,
Auth: []AuthMethod{
RetryableAuthMethod(PasswordCallback(func() (string, error) {
n--
if n == 0 {
return "right", nil
} else {
return "wrong", nil
}
}), tries),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
c1, c2, err := netPipe()
if err != nil {
t.Fatalf("netPipe: %v", err)
}
defer c1.Close()
defer c2.Close()
go newServer(c1, serverConfig)
_, _, _, err = NewClientConn(c2, "", clientConfig)
if tries > 2 {
if err == nil {
t.Fatalf("client: got no error, want %s", expectedErr)
} else if err.Error() != expectedErr.Error() {
t.Fatalf("client: got %s, want %s", err, expectedErr)
}
} else {
if err != nil {
t.Fatalf("client: got %s, want no error", err)
}
}
}
}
// Test if authentication attempts are correctly limited on server
// when more public keys are provided then MaxAuthTries
func TestClientAuthMaxAuthTriesPublicKey(t *testing.T) {
signers := []Signer{}
for i := 0; i < 6; i++ {
signers = append(signers, testSigners["dsa"])
}
validConfig := &ClientConfig{
User: "testuser",
Auth: []AuthMethod{
PublicKeys(append([]Signer{testSigners["rsa"]}, signers...)...),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, validConfig); err != nil {
t.Fatalf("unable to dial remote side: %s", err)
}
expectedErr := fmt.Errorf("ssh: handshake failed: %v", &disconnectMsg{
Reason: 2,
Message: "too many authentication failures",
})
invalidConfig := &ClientConfig{
User: "testuser",
Auth: []AuthMethod{
PublicKeys(append(signers, testSigners["rsa"])...),
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
if err := tryAuth(t, invalidConfig); err == nil {
t.Fatalf("client: got no error, want %s", expectedErr)
} else if err.Error() != expectedErr.Error() {
t.Fatalf("client: got %s, want %s", err, expectedErr)
}
}

42
ssh/client_test.go
View file

@ -6,6 +6,7 @@ package ssh
import (
"net"
"strings"
"testing"
)
@ -13,6 +14,7 @@ func testClientVersion(t *testing.T, config *ClientConfig, expected string) {
clientConn, serverConn := net.Pipe()
defer clientConn.Close()
receivedVersion := make(chan string, 1)
config.HostKeyCallback = InsecureIgnoreHostKey()
go func() {
version, err := readVersion(serverConn)
if err != nil {
@ -37,3 +39,43 @@ func TestCustomClientVersion(t *testing.T) {
func TestDefaultClientVersion(t *testing.T) {
testClientVersion(t, &ClientConfig{}, packageVersion)
}
func TestHostKeyCheck(t *testing.T) {
for _, tt := range []struct {
name string
wantError string
key PublicKey
}{
{"no callback", "must specify HostKeyCallback", nil},
{"correct key", "", testSigners["rsa"].PublicKey()},
{"mismatch", "mismatch", testSigners["ecdsa"].PublicKey()},
} {
c1, c2, err := netPipe()
if err != nil {
t.Fatalf("netPipe: %v", err)
}
defer c1.Close()
defer c2.Close()
serverConf := &ServerConfig{
NoClientAuth: true,
}
serverConf.AddHostKey(testSigners["rsa"])
go NewServerConn(c1, serverConf)
clientConf := ClientConfig{
User: "user",
}
if tt.key != nil {
clientConf.HostKeyCallback = FixedHostKey(tt.key)
}
_, _, _, err = NewClientConn(c2, "", &clientConf)
if err != nil {
if tt.wantError == "" || !strings.Contains(err.Error(), tt.wantError) {
t.Errorf("%s: got error %q, missing %q", tt.name, err.Error(), tt.wantError)
}
} else if tt.wantError != "" {
t.Errorf("%s: succeeded, but want error string %q", tt.name, tt.wantError)
}
}
}

31
ssh/common.go
View file

@ -9,6 +9,7 @@ import (
"crypto/rand"
"fmt"
"io"
"math"
"sync"
_ "crypto/sha1"
@ -40,7 +41,7 @@ var supportedKexAlgos = []string{
kexAlgoDH14SHA1, kexAlgoDH1SHA1,
}
// supportedKexAlgos specifies the supported host-key algorithms (i.e. methods
// supportedHostKeyAlgos specifies the supported host-key algorithms (i.e. methods
// of authenticating servers) in preference order.
var supportedHostKeyAlgos = []string{
CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01,
@ -56,7 +57,7 @@ var supportedHostKeyAlgos = []string{
// This is based on RFC 4253, section 6.4, but with hmac-md5 variants removed
// because they have reached the end of their useful life.
var supportedMACs = []string{
"hmac-sha2-256", "hmac-sha1", "hmac-sha1-96",
"hmac-sha2-256-etm@openssh.com", "hmac-sha2-256", "hmac-sha1", "hmac-sha1-96",
}
var supportedCompressions = []string{compressionNone}
@ -104,6 +105,21 @@ type directionAlgorithms struct {
Compression string
}
// rekeyBytes returns a rekeying intervals in bytes.
func (a *directionAlgorithms) rekeyBytes() int64 {
// According to RFC4344 block ciphers should rekey after
// 2^(BLOCKSIZE/4) blocks. For all AES flavors BLOCKSIZE is
// 128.
switch a.Cipher {
case "aes128-ctr", "aes192-ctr", "aes256-ctr", gcmCipherID, aes128cbcID:
return 16 * (1 << 32)
}
// For others, stick with RFC4253 recommendation to rekey after 1 Gb of data.
return 1 << 30
}
type algorithms struct {
kex string
hostKey string
@ -171,7 +187,7 @@ type Config struct {
// The maximum number of bytes sent or received after which a
// new key is negotiated. It must be at least 256. If
// unspecified, 1 gigabyte is used.
// unspecified, a size suitable for the chosen cipher is used.
RekeyThreshold uint64
// The allowed key exchanges algorithms. If unspecified then a
@ -215,11 +231,12 @@ func (c *Config) SetDefaults() {
}
if c.RekeyThreshold == 0 {
// RFC 4253, section 9 suggests rekeying after 1G.
c.RekeyThreshold = 1 << 30
}
if c.RekeyThreshold < minRekeyThreshold {
// cipher specific default
} else if c.RekeyThreshold < minRekeyThreshold {
c.RekeyThreshold = minRekeyThreshold
} else if c.RekeyThreshold >= math.MaxInt64 {
// Avoid weirdness if somebody uses -1 as a threshold.
c.RekeyThreshold = math.MaxInt64
}
}

2
ssh/connection.go
View file

@ -25,7 +25,7 @@ type ConnMetadata interface {
// User returns the user ID for this connection.
User() string
// SessionID returns the sesson hash, also denoted by H.
// SessionID returns the session hash, also denoted by H.
SessionID() []byte
// ClientVersion returns the client's version string as hashed

3
ssh/doc.go
View file

@ -19,5 +19,8 @@ others.
References:
[PROTOCOL.certkeys]: http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL.certkeys?rev=HEAD
[SSH-PARAMETERS]: http://www.iana.org/assignments/ssh-parameters/ssh-parameters.xml#ssh-parameters-1
This package does not fall under the stability promise of the Go language itself,
so its API may be changed when pressing needs arise.
*/
package ssh

137
ssh/example_test.go
View file

@ -5,21 +5,45 @@
package ssh_test
import (
"bufio"
"bytes"
"fmt"
"io/ioutil"
"log"
"net"
"net/http"
"os"
"path/filepath"
"strings"
"golang.org/x/crypto/ssh"
"golang.org/x/crypto/ssh/terminal"
)
func ExampleNewServerConn() {
// Public key authentication is done by comparing
// the public key of a received connection
// with the entries in the authorized_keys file.
authorizedKeysBytes, err := ioutil.ReadFile("authorized_keys")
if err != nil {
log.Fatalf("Failed to load authorized_keys, err: %v", err)
}
authorizedKeysMap := map[string]bool{}
for len(authorizedKeysBytes) > 0 {
pubKey, _, _, rest, err := ssh.ParseAuthorizedKey(authorizedKeysBytes)
if err != nil {
log.Fatal(err)
}
authorizedKeysMap[string(pubKey.Marshal())] = true
authorizedKeysBytes = rest
}
// An SSH server is represented by a ServerConfig, which holds
// certificate details and handles authentication of ServerConns.
config := &ssh.ServerConfig{
// Remove to disable password auth.
PasswordCallback: func(c ssh.ConnMetadata, pass []byte) (*ssh.Permissions, error) {
// Should use constant-time compare (or better, salt+hash) in
// a production setting.
@ -28,16 +52,29 @@ func ExampleNewServerConn() {
}
return nil, fmt.Errorf("password rejected for %q", c.User())
},
// Remove to disable public key auth.
PublicKeyCallback: func(c ssh.ConnMetadata, pubKey ssh.PublicKey) (*ssh.Permissions, error) {
if authorizedKeysMap[string(pubKey.Marshal())] {
return &ssh.Permissions{
// Record the public key used for authentication.
Extensions: map[string]string{
"pubkey-fp": ssh.FingerprintSHA256(pubKey),
},
}, nil
}
return nil, fmt.Errorf("unknown public key for %q", c.User())
},
}
privateBytes, err := ioutil.ReadFile("id_rsa")
if err != nil {
panic("Failed to load private key")
log.Fatal("Failed to load private key: ", err)
}
private, err := ssh.ParsePrivateKey(privateBytes)
if err != nil {
panic("Failed to parse private key")
log.Fatal("Failed to parse private key: ", err)
}
config.AddHostKey(private)
@ -46,19 +83,21 @@ func ExampleNewServerConn() {
// accepted.
listener, err := net.Listen("tcp", "0.0.0.0:2022")
if err != nil {
panic("failed to listen for connection")
log.Fatal("failed to listen for connection: ", err)
}
nConn, err := listener.Accept()
if err != nil {
panic("failed to accept incoming connection")
log.Fatal("failed to accept incoming connection: ", err)
}
// Before use, a handshake must be performed on the incoming
// net.Conn.
_, chans, reqs, err := ssh.NewServerConn(nConn, config)
conn, chans, reqs, err := ssh.NewServerConn(nConn, config)
if err != nil {
panic("failed to handshake")
log.Fatal("failed to handshake: ", err)
}
log.Printf("logged in with key %s", conn.Permissions.Extensions["pubkey-fp"])
// The incoming Request channel must be serviced.
go ssh.DiscardRequests(reqs)
@ -74,7 +113,7 @@ func ExampleNewServerConn() {
}
channel, requests, err := newChannel.Accept()
if err != nil {
panic("could not accept channel.")
log.Fatalf("Could not accept channel: %v", err)
}
// Sessions have out-of-band requests such as "shell",
@ -82,18 +121,7 @@ func ExampleNewServerConn() {
// "shell" request.
go func(in <-chan *ssh.Request) {
for req := range in {
ok := false
switch req.Type {
case "shell":
ok = true
if len(req.Payload) > 0 {
// We don't accept any
// commands, only the
// default shell.
ok = false
}
}
req.Reply(ok, nil)
req.Reply(req.Type == "shell", nil)
}
}(requests)
@ -112,27 +140,70 @@ func ExampleNewServerConn() {
}
}
func ExampleHostKeyCheck() {
// Every client must provide a host key check. Here is a
// simple-minded parse of OpenSSH's known_hosts file
host := "hostname"
file, err := os.Open(filepath.Join(os.Getenv("HOME"), ".ssh", "known_hosts"))
if err != nil {
log.Fatal(err)
}
defer file.Close()
scanner := bufio.NewScanner(file)
var hostKey ssh.PublicKey
for scanner.Scan() {
fields := strings.Split(scanner.Text(), " ")
if len(fields) != 3 {
continue
}
if strings.Contains(fields[0], host) {
var err error
hostKey, _, _, _, err = ssh.ParseAuthorizedKey(scanner.Bytes())
if err != nil {
log.Fatalf("error parsing %q: %v", fields[2], err)
}
break
}
}
if hostKey == nil {
log.Fatalf("no hostkey for %s", host)
}
config := ssh.ClientConfig{
User: os.Getenv("USER"),
HostKeyCallback: ssh.FixedHostKey(hostKey),
}
_, err = ssh.Dial("tcp", host+":22", &config)
log.Println(err)
}
func ExampleDial() {
var hostKey ssh.PublicKey
// An SSH client is represented with a ClientConn.
//
// To authenticate with the remote server you must pass at least one
// implementation of AuthMethod via the Auth field in ClientConfig.
// implementation of AuthMethod via the Auth field in ClientConfig,
// and provide a HostKeyCallback.
config := &ssh.ClientConfig{
User: "username",
Auth: []ssh.AuthMethod{
ssh.Password("yourpassword"),
},
HostKeyCallback: ssh.FixedHostKey(hostKey),
}
client, err := ssh.Dial("tcp", "yourserver.com:22", config)
if err != nil {
panic("Failed to dial: " + err.Error())
log.Fatal("Failed to dial: ", err)
}
// Each ClientConn can support multiple interactive sessions,
// represented by a Session.
session, err := client.NewSession()
if err != nil {
panic("Failed to create session: " + err.Error())
log.Fatal("Failed to create session: ", err)
}
defer session.Close()
@ -141,12 +212,13 @@ func ExampleDial() {
var b bytes.Buffer
session.Stdout = &b
if err := session.Run("/usr/bin/whoami"); err != nil {
panic("Failed to run: " + err.Error())
log.Fatal("Failed to run: " + err.Error())
}
fmt.Println(b.String())
}
func ExamplePublicKeys() {
var hostKey ssh.PublicKey
// A public key may be used to authenticate against the remote
// server by using an unencrypted PEM-encoded private key file.
//
@ -169,6 +241,7 @@ func ExamplePublicKeys() {
// Use the PublicKeys method for remote authentication.
ssh.PublicKeys(signer),
},
HostKeyCallback: ssh.FixedHostKey(hostKey),
}
// Connect to the remote server and perform the SSH handshake.
@ -180,23 +253,25 @@ func ExamplePublicKeys() {
}
func ExampleClient_Listen() {
var hostKey ssh.PublicKey
config := &ssh.ClientConfig{
User: "username",
Auth: []ssh.AuthMethod{
ssh.Password("password"),
},
HostKeyCallback: ssh.FixedHostKey(hostKey),
}
// Dial your ssh server.
conn, err := ssh.Dial("tcp", "localhost:22", config)
if err != nil {
log.Fatalf("unable to connect: %s", err)
log.Fatal("unable to connect: ", err)
}
defer conn.Close()
// Request the remote side to open port 8080 on all interfaces.
l, err := conn.Listen("tcp", "0.0.0.0:8080")
if err != nil {
log.Fatalf("unable to register tcp forward: %v", err)
log.Fatal("unable to register tcp forward: ", err)
}
defer l.Close()
@ -207,23 +282,25 @@ func ExampleClient_Listen() {
}
func ExampleSession_RequestPty() {
var hostKey ssh.PublicKey
// Create client config
config := &ssh.ClientConfig{
User: "username",
Auth: []ssh.AuthMethod{
ssh.Password("password"),
},
HostKeyCallback: ssh.FixedHostKey(hostKey),
}
// Connect to ssh server
conn, err := ssh.Dial("tcp", "localhost:22", config)
if err != nil {
log.Fatalf("unable to connect: %s", err)
log.Fatal("unable to connect: ", err)
}
defer conn.Close()
// Create a session
session, err := conn.NewSession()
if err != nil {
log.Fatalf("unable to create session: %s", err)
log.Fatal("unable to create session: ", err)
}
defer session.Close()
// Set up terminal modes
@ -233,11 +310,11 @@ func ExampleSession_RequestPty() {
ssh.TTY_OP_OSPEED: 14400, // output speed = 14.4kbaud
}
// Request pseudo terminal
if err := session.RequestPty("xterm", 80, 40, modes); err != nil {
log.Fatalf("request for pseudo terminal failed: %s", err)
if err := session.RequestPty("xterm", 40, 80, modes); err != nil {
log.Fatal("request for pseudo terminal failed: ", err)
}
// Start remote shell
if err := session.Shell(); err != nil {
log.Fatalf("failed to start shell: %s", err)
log.Fatal("failed to start shell: ", err)
}
}

462
ssh/handshake.go
View file

@ -19,6 +19,11 @@ import (
// messages are wrong when using ECDH.
const debugHandshake = false
// chanSize sets the amount of buffering SSH connections. This is
// primarily for testing: setting chanSize=0 uncovers deadlocks more
// quickly.
const chanSize = 16
// keyingTransport is a packet based transport that supports key
// changes. It need not be thread-safe. It should pass through
// msgNewKeys in both directions.
@ -53,34 +58,60 @@ type handshakeTransport struct {
incoming chan []byte
readError error
mu sync.Mutex
writeError error
sentInitPacket []byte
sentInitMsg *kexInitMsg
pendingPackets [][]byte // Used when a key exchange is in progress.
// If the read loop wants to schedule a kex, it pings this
// channel, and the write loop will send out a kex
// message.
requestKex chan struct{}
// If the other side requests or confirms a kex, its kexInit
// packet is sent here for the write loop to find it.
startKex chan *pendingKex
// data for host key checking
hostKeyCallback func(hostname string, remote net.Addr, key PublicKey) error
hostKeyCallback HostKeyCallback
dialAddress string
remoteAddr net.Addr
readSinceKex uint64
// Algorithms agreed in the last key exchange.
algorithms *algorithms
// Protects the writing side of the connection
mu sync.Mutex
cond *sync.Cond
sentInitPacket []byte
sentInitMsg *kexInitMsg
writtenSinceKex uint64
writeError error
readPacketsLeft uint32
readBytesLeft int64
writePacketsLeft uint32
writeBytesLeft int64
// The session ID or nil if first kex did not complete yet.
sessionID []byte
}
type pendingKex struct {
otherInit []byte
done chan error
}
func newHandshakeTransport(conn keyingTransport, config *Config, clientVersion, serverVersion []byte) *handshakeTransport {
t := &handshakeTransport{
conn: conn,
serverVersion: serverVersion,
clientVersion: clientVersion,
incoming: make(chan []byte, 16),
config: config,
incoming: make(chan []byte, chanSize),
requestKex: make(chan struct{}, 1),
startKex: make(chan *pendingKex, 1),
config: config,
}
t.cond = sync.NewCond(&t.mu)
t.resetReadThresholds()
t.resetWriteThresholds()
// We always start with a mandatory key exchange.
t.requestKex <- struct{}{}
return t
}
@ -95,6 +126,7 @@ func newClientTransport(conn keyingTransport, clientVersion, serverVersion []byt
t.hostKeyAlgorithms = supportedHostKeyAlgos
}
go t.readLoop()
go t.kexLoop()
return t
}
@ -102,6 +134,7 @@ func newServerTransport(conn keyingTransport, clientVersion, serverVersion []byt
t := newHandshakeTransport(conn, &config.Config, clientVersion, serverVersion)
t.hostKeys = config.hostKeys
go t.readLoop()
go t.kexLoop()
return t
}
@ -109,6 +142,20 @@ func (t *handshakeTransport) getSessionID() []byte {
return t.sessionID
}
// waitSession waits for the session to be established. This should be
// the first thing to call after instantiating handshakeTransport.
func (t *handshakeTransport) waitSession() error {
p, err := t.readPacket()
if err != nil {
return err
}
if p[0] != msgNewKeys {
return fmt.Errorf("ssh: first packet should be msgNewKeys")
}
return nil
}
func (t *handshakeTransport) id() string {
if len(t.hostKeys) > 0 {
return "server"
@ -116,6 +163,20 @@ func (t *handshakeTransport) id() string {
return "client"
}
func (t *handshakeTransport) printPacket(p []byte, write bool) {
action := "got"
if write {
action = "sent"
}
if p[0] == msgChannelData || p[0] == msgChannelExtendedData {
log.Printf("%s %s data (packet %d bytes)", t.id(), action, len(p))
} else {
msg, err := decode(p)
log.Printf("%s %s %T %v (%v)", t.id(), action, msg, msg, err)
}
}
func (t *handshakeTransport) readPacket() ([]byte, error) {
p, ok := <-t.incoming
if !ok {
@ -125,8 +186,10 @@ func (t *handshakeTransport) readPacket() ([]byte, error) {
}
func (t *handshakeTransport) readLoop() {
first := true
for {
p, err := t.readOnePacket()
p, err := t.readOnePacket(first)
first = false
if err != nil {
t.readError = err
close(t.incoming)
@ -138,67 +201,217 @@ func (t *handshakeTransport) readLoop() {
t.incoming <- p
}
// If we can't read, declare the writing part dead too.
t.mu.Lock()
defer t.mu.Unlock()
if t.writeError == nil {
t.writeError = t.readError
}
t.cond.Broadcast()
// Stop writers too.
t.recordWriteError(t.readError)
// Unblock the writer should it wait for this.
close(t.startKex)
// Don't close t.requestKex; it's also written to from writePacket.
}
func (t *handshakeTransport) readOnePacket() ([]byte, error) {
if t.readSinceKex > t.config.RekeyThreshold {
if err := t.requestKeyChange(); err != nil {
return nil, err
func (t *handshakeTransport) pushPacket(p []byte) error {
if debugHandshake {
t.printPacket(p, true)
}
return t.conn.writePacket(p)
}
func (t *handshakeTransport) getWriteError() error {
t.mu.Lock()
defer t.mu.Unlock()
return t.writeError
}
func (t *handshakeTransport) recordWriteError(err error) {
t.mu.Lock()
defer t.mu.Unlock()
if t.writeError == nil && err != nil {
t.writeError = err
}
}
func (t *handshakeTransport) requestKeyExchange() {
select {
case t.requestKex <- struct{}{}:
default:
// something already requested a kex, so do nothing.
}
}
func (t *handshakeTransport) resetWriteThresholds() {
t.writePacketsLeft = packetRekeyThreshold
if t.config.RekeyThreshold > 0 {
t.writeBytesLeft = int64(t.config.RekeyThreshold)
} else if t.algorithms != nil {
t.writeBytesLeft = t.algorithms.w.rekeyBytes()
} else {
t.writeBytesLeft = 1 << 30
}
}
func (t *handshakeTransport) kexLoop() {
write:
for t.getWriteError() == nil {
var request *pendingKex
var sent bool
for request == nil || !sent {
var ok bool
select {
case request, ok = <-t.startKex:
if !ok {
break write
}
case <-t.requestKex:
break
}
if !sent {
if err := t.sendKexInit(); err != nil {
t.recordWriteError(err)
break
}
sent = true
}
}
if err := t.getWriteError(); err != nil {
if request != nil {
request.done <- err
}
break
}
// We're not servicing t.requestKex, but that is OK:
// we never block on sending to t.requestKex.
// We're not servicing t.startKex, but the remote end
// has just sent us a kexInitMsg, so it can't send
// another key change request, until we close the done
// channel on the pendingKex request.
err := t.enterKeyExchange(request.otherInit)
t.mu.Lock()
t.writeError = err
t.sentInitPacket = nil
t.sentInitMsg = nil
t.resetWriteThresholds()
// we have completed the key exchange. Since the
// reader is still blocked, it is safe to clear out
// the requestKex channel. This avoids the situation
// where: 1) we consumed our own request for the
// initial kex, and 2) the kex from the remote side
// caused another send on the requestKex channel,
clear:
for {
select {
case <-t.requestKex:
//
default:
break clear
}
}
request.done <- t.writeError
// kex finished. Push packets that we received while
// the kex was in progress. Don't look at t.startKex
// and don't increment writtenSinceKex: if we trigger
// another kex while we are still busy with the last
// one, things will become very confusing.
for _, p := range t.pendingPackets {
t.writeError = t.pushPacket(p)
if t.writeError != nil {
break
}
}
t.pendingPackets = t.pendingPackets[:0]
t.mu.Unlock()
}
// drain startKex channel. We don't service t.requestKex
// because nobody does blocking sends there.
go func() {
for init := range t.startKex {
init.done <- t.writeError
}
}()
// Unblock reader.
t.conn.Close()
}
// The protocol uses uint32 for packet counters, so we can't let them
// reach 1<<32. We will actually read and write more packets than
// this, though: the other side may send more packets, and after we
// hit this limit on writing we will send a few more packets for the
// key exchange itself.
const packetRekeyThreshold = (1 << 31)
func (t *handshakeTransport) resetReadThresholds() {
t.readPacketsLeft = packetRekeyThreshold
if t.config.RekeyThreshold > 0 {
t.readBytesLeft = int64(t.config.RekeyThreshold)
} else if t.algorithms != nil {
t.readBytesLeft = t.algorithms.r.rekeyBytes()
} else {
t.readBytesLeft = 1 << 30
}
}
func (t *handshakeTransport) readOnePacket(first bool) ([]byte, error) {
p, err := t.conn.readPacket()
if err != nil {
return nil, err
}
t.readSinceKex += uint64(len(p))
if debugHandshake {
if p[0] == msgChannelData || p[0] == msgChannelExtendedData {
log.Printf("%s got data (packet %d bytes)", t.id(), len(p))
} else {
msg, err := decode(p)
log.Printf("%s got %T %v (%v)", t.id(), msg, msg, err)
}
if t.readPacketsLeft > 0 {
t.readPacketsLeft--
} else {
t.requestKeyExchange()
}
if t.readBytesLeft > 0 {
t.readBytesLeft -= int64(len(p))
} else {
t.requestKeyExchange()
}
if debugHandshake {
t.printPacket(p, false)
}
if first && p[0] != msgKexInit {
return nil, fmt.Errorf("ssh: first packet should be msgKexInit")
}
if p[0] != msgKexInit {
return p, nil
}
t.mu.Lock()
firstKex := t.sessionID == nil
err = t.enterKeyExchangeLocked(p)
if err != nil {
// drop connection
t.conn.Close()
t.writeError = err
kex := pendingKex{
done: make(chan error, 1),
otherInit: p,
}
t.startKex <- &kex
err = <-kex.done
if debugHandshake {
log.Printf("%s exited key exchange (first %v), err %v", t.id(), firstKex, err)
}
// Unblock writers.
t.sentInitMsg = nil
t.sentInitPacket = nil
t.cond.Broadcast()
t.writtenSinceKex = 0
t.mu.Unlock()
if err != nil {
return nil, err
}
t.readSinceKex = 0
t.resetReadThresholds()
// By default, a key exchange is hidden from higher layers by
// translating it into msgIgnore.
@ -213,61 +426,16 @@ func (t *handshakeTransport) readOnePacket() ([]byte, error) {
return successPacket, nil
}
// keyChangeCategory describes whether a key exchange is the first on a
// connection, or a subsequent one.
type keyChangeCategory bool
const (
firstKeyExchange keyChangeCategory = true
subsequentKeyExchange keyChangeCategory = false
)
// sendKexInit sends a key change message, and returns the message
// that was sent. After initiating the key change, all writes will be
// blocked until the change is done, and a failed key change will
// close the underlying transport. This function is safe for
// concurrent use by multiple goroutines.
func (t *handshakeTransport) sendKexInit(isFirst keyChangeCategory) error {
var err error
// sendKexInit sends a key change message.
func (t *handshakeTransport) sendKexInit() error {
t.mu.Lock()
// If this is the initial key change, but we already have a sessionID,
// then do nothing because the key exchange has already completed
// asynchronously.
if !isFirst || t.sessionID == nil {
_, _, err = t.sendKexInitLocked(isFirst)
}
t.mu.Unlock()
if err != nil {
return err
}
if isFirst {
if packet, err := t.readPacket(); err != nil {
return err
} else if packet[0] != msgNewKeys {
return unexpectedMessageError(msgNewKeys, packet[0])
}
}
return nil
}
func (t *handshakeTransport) requestInitialKeyChange() error {
return t.sendKexInit(firstKeyExchange)
}
func (t *handshakeTransport) requestKeyChange() error {
return t.sendKexInit(subsequentKeyExchange)
}
// sendKexInitLocked sends a key change message. t.mu must be locked
// while this happens.
func (t *handshakeTransport) sendKexInitLocked(isFirst keyChangeCategory) (*kexInitMsg, []byte, error) {
// kexInits may be sent either in response to the other side,
// or because our side wants to initiate a key change, so we
// may have already sent a kexInit. In that case, don't send a
// second kexInit.
defer t.mu.Unlock()
if t.sentInitMsg != nil {
return t.sentInitMsg, t.sentInitPacket, nil
// kexInits may be sent either in response to the other side,
// or because our side wants to initiate a key change, so we
// may have already sent a kexInit. In that case, don't send a
// second kexInit.
return nil
}
msg := &kexInitMsg{
@ -295,53 +463,65 @@ func (t *handshakeTransport) sendKexInitLocked(isFirst keyChangeCategory) (*kexI
packetCopy := make([]byte, len(packet))
copy(packetCopy, packet)
if err := t.conn.writePacket(packetCopy); err != nil {
return nil, nil, err
if err := t.pushPacket(packetCopy); err != nil {
return err
}
t.sentInitMsg = msg
t.sentInitPacket = packet
return msg, packet, nil
return nil
}
func (t *handshakeTransport) writePacket(p []byte) error {
t.mu.Lock()
defer t.mu.Unlock()
if t.writtenSinceKex > t.config.RekeyThreshold {
t.sendKexInitLocked(subsequentKeyExchange)
}
for t.sentInitMsg != nil && t.writeError == nil {
t.cond.Wait()
}
if t.writeError != nil {
return t.writeError
}
t.writtenSinceKex += uint64(len(p))
switch p[0] {
case msgKexInit:
return errors.New("ssh: only handshakeTransport can send kexInit")
case msgNewKeys:
return errors.New("ssh: only handshakeTransport can send newKeys")
default:
return t.conn.writePacket(p)
}
t.mu.Lock()
defer t.mu.Unlock()
if t.writeError != nil {
return t.writeError
}
if t.sentInitMsg != nil {
// Copy the packet so the writer can reuse the buffer.
cp := make([]byte, len(p))
copy(cp, p)
t.pendingPackets = append(t.pendingPackets, cp)
return nil
}
if t.writeBytesLeft > 0 {
t.writeBytesLeft -= int64(len(p))
} else {
t.requestKeyExchange()
}
if t.writePacketsLeft > 0 {
t.writePacketsLeft--
} else {
t.requestKeyExchange()
}
if err := t.pushPacket(p); err != nil {
t.writeError = err
}
return nil
}
func (t *handshakeTransport) Close() error {
return t.conn.Close()
}
// enterKeyExchange runs the key exchange. t.mu must be held while running this.
func (t *handshakeTransport) enterKeyExchangeLocked(otherInitPacket []byte) error {
func (t *handshakeTransport) enterKeyExchange(otherInitPacket []byte) error {
if debugHandshake {
log.Printf("%s entered key exchange", t.id())
}
myInit, myInitPacket, err := t.sendKexInitLocked(subsequentKeyExchange)
if err != nil {
return err
}
otherInit := &kexInitMsg{}
if err := Unmarshal(otherInitPacket, otherInit); err != nil {
@ -352,20 +532,20 @@ func (t *handshakeTransport) enterKeyExchangeLocked(otherInitPacket []byte) erro
clientVersion: t.clientVersion,
serverVersion: t.serverVersion,
clientKexInit: otherInitPacket,
serverKexInit: myInitPacket,
serverKexInit: t.sentInitPacket,
}
clientInit := otherInit
serverInit := myInit
serverInit := t.sentInitMsg
if len(t.hostKeys) == 0 {
clientInit = myInit
serverInit = otherInit
clientInit, serverInit = serverInit, clientInit
magics.clientKexInit = myInitPacket
magics.clientKexInit = t.sentInitPacket
magics.serverKexInit = otherInitPacket
}
algs, err := findAgreedAlgorithms(clientInit, serverInit)
var err error
t.algorithms, err = findAgreedAlgorithms(clientInit, serverInit)
if err != nil {
return err
}
@ -388,16 +568,16 @@ func (t *handshakeTransport) enterKeyExchangeLocked(otherInitPacket []byte) erro
}
}
kex, ok := kexAlgoMap[algs.kex]
kex, ok := kexAlgoMap[t.algorithms.kex]
if !ok {
return fmt.Errorf("ssh: unexpected key exchange algorithm %v", algs.kex)
return fmt.Errorf("ssh: unexpected key exchange algorithm %v", t.algorithms.kex)
}
var result *kexResult
if len(t.hostKeys) > 0 {
result, err = t.server(kex, algs, &magics)
result, err = t.server(kex, t.algorithms, &magics)
} else {
result, err = t.client(kex, algs, &magics)
result, err = t.client(kex, t.algorithms, &magics)
}
if err != nil {
@ -409,7 +589,9 @@ func (t *handshakeTransport) enterKeyExchangeLocked(otherInitPacket []byte) erro
}
result.SessionID = t.sessionID
t.conn.prepareKeyChange(algs, result)
if err := t.conn.prepareKeyChange(t.algorithms, result); err != nil {
return err
}
if err = t.conn.writePacket([]byte{msgNewKeys}); err != nil {
return err
}
@ -449,11 +631,9 @@ func (t *handshakeTransport) client(kex kexAlgorithm, algs *algorithms, magics *
return nil, err
}
if t.hostKeyCallback != nil {
err = t.hostKeyCallback(t.dialAddress, t.remoteAddr, hostKey)
if err != nil {
return nil, err
}
err = t.hostKeyCallback(t.dialAddress, t.remoteAddr, hostKey)
if err != nil {
return nil, err
}
return result, nil

459
ssh/handshake_test.go
View file

@ -9,6 +9,7 @@ import (
"crypto/rand"
"errors"
"fmt"
"io"
"net"
"reflect"
"runtime"
@ -41,7 +42,10 @@ func (t *testChecker) Check(dialAddr string, addr net.Addr, key PublicKey) error
func netPipe() (net.Conn, net.Conn, error) {
listener, err := net.Listen("tcp", "127.0.0.1:0")
if err != nil {
return nil, nil, err
listener, err = net.Listen("tcp", "[::1]:0")
if err != nil {
return nil, nil, err
}
}
defer listener.Close()
c1, err := net.Dial("tcp", listener.Addr().String())
@ -58,14 +62,46 @@ func netPipe() (net.Conn, net.Conn, error) {
return c1, c2, nil
}
func handshakePair(clientConf *ClientConfig, addr string) (client *handshakeTransport, server *handshakeTransport, err error) {
// noiseTransport inserts ignore messages to check that the read loop
// and the key exchange filters out these messages.
type noiseTransport struct {
keyingTransport
}
func (t *noiseTransport) writePacket(p []byte) error {
ignore := []byte{msgIgnore}
if err := t.keyingTransport.writePacket(ignore); err != nil {
return err
}
debug := []byte{msgDebug, 1, 2, 3}
if err := t.keyingTransport.writePacket(debug); err != nil {
return err
}
return t.keyingTransport.writePacket(p)
}
func addNoiseTransport(t keyingTransport) keyingTransport {
return &noiseTransport{t}
}
// handshakePair creates two handshakeTransports connected with each
// other. If the noise argument is true, both transports will try to
// confuse the other side by sending ignore and debug messages.
func handshakePair(clientConf *ClientConfig, addr string, noise bool) (client *handshakeTransport, server *handshakeTransport, err error) {
a, b, err := netPipe()
if err != nil {
return nil, nil, err
}
trC := newTransport(a, rand.Reader, true)
trS := newTransport(b, rand.Reader, false)
var trC, trS keyingTransport
trC = newTransport(a, rand.Reader, true)
trS = newTransport(b, rand.Reader, false)
if noise {
trC = addNoiseTransport(trC)
trS = addNoiseTransport(trS)
}
clientConf.SetDefaults()
v := []byte("version")
@ -77,6 +113,13 @@ func handshakePair(clientConf *ClientConfig, addr string) (client *handshakeTran
serverConf.SetDefaults()
server = newServerTransport(trS, v, v, serverConf)
if err := server.waitSession(); err != nil {
return nil, nil, fmt.Errorf("server.waitSession: %v", err)
}
if err := client.waitSession(); err != nil {
return nil, nil, fmt.Errorf("client.waitSession: %v", err)
}
return client, server, nil
}
@ -84,8 +127,14 @@ func TestHandshakeBasic(t *testing.T) {
if runtime.GOOS == "plan9" {
t.Skip("see golang.org/issue/7237")
}
checker := &testChecker{}
trC, trS, err := handshakePair(&ClientConfig{HostKeyCallback: checker.Check}, "addr")
checker := &syncChecker{
waitCall: make(chan int, 10),
called: make(chan int, 10),
}
checker.waitCall <- 1
trC, trS, err := handshakePair(&ClientConfig{HostKeyCallback: checker.Check}, "addr", false)
if err != nil {
t.Fatalf("handshakePair: %v", err)
}
@ -93,240 +142,195 @@ func TestHandshakeBasic(t *testing.T) {
defer trC.Close()
defer trS.Close()
// Let first kex complete normally.
<-checker.called
clientDone := make(chan int, 0)
gotHalf := make(chan int, 0)
const N = 20
go func() {
defer close(clientDone)
// Client writes a bunch of stuff, and does a key
// change in the middle. This should not confuse the
// handshake in progress
for i := 0; i < 10; i++ {
// handshake in progress. We do this twice, so we test
// that the packet buffer is reset correctly.
for i := 0; i < N; i++ {
p := []byte{msgRequestSuccess, byte(i)}
if err := trC.writePacket(p); err != nil {
t.Fatalf("sendPacket: %v", err)
}
if i == 5 {
if (i % 10) == 5 {
<-gotHalf
// halfway through, we request a key change.
err := trC.sendKexInit(subsequentKeyExchange)
if err != nil {
t.Fatalf("sendKexInit: %v", err)
}
trC.requestKeyExchange()
// Wait until we can be sure the key
// change has really started before we
// write more.
<-checker.called
}
if (i % 10) == 7 {
// write some packets until the kex
// completes, to test buffering of
// packets.
checker.waitCall <- 1
}
}
trC.Close()
}()
// Server checks that client messages come in cleanly
i := 0
for {
p, err := trS.readPacket()
err = nil
for ; i < N; i++ {
var p []byte
p, err = trS.readPacket()
if err != nil {
break
}
if p[0] == msgNewKeys {
continue
if (i % 10) == 5 {
gotHalf <- 1
}
want := []byte{msgRequestSuccess, byte(i)}
if bytes.Compare(p, want) != 0 {
t.Errorf("message %d: got %q, want %q", i, p, want)
t.Errorf("message %d: got %v, want %v", i, p, want)
}
i++
}
if i != 10 {
<-clientDone
if err != nil && err != io.EOF {
t.Fatalf("server error: %v", err)
}
if i != N {
t.Errorf("received %d messages, want 10.", i)
}
// If all went well, we registered exactly 1 key change.
if len(checker.calls) != 1 {
t.Fatalf("got %d host key checks, want 1", len(checker.calls))
}
pub := testSigners["ecdsa"].PublicKey()
want := fmt.Sprintf("%s %v %s %x", "addr", trC.remoteAddr, pub.Type(), pub.Marshal())
if want != checker.calls[0] {
t.Errorf("got %q want %q for host key check", checker.calls[0], want)
}
}
func TestHandshakeError(t *testing.T) {
checker := &testChecker{}
trC, trS, err := handshakePair(&ClientConfig{HostKeyCallback: checker.Check}, "bad")
if err != nil {
t.Fatalf("handshakePair: %v", err)
}
defer trC.Close()
defer trS.Close()
// send a packet
packet := []byte{msgRequestSuccess, 42}
if err := trC.writePacket(packet); err != nil {
t.Errorf("writePacket: %v", err)
}
// Now request a key change.
err = trC.sendKexInit(subsequentKeyExchange)
if err != nil {
t.Errorf("sendKexInit: %v", err)
}
// the key change will fail, and afterwards we can't write.
if err := trC.writePacket([]byte{msgRequestSuccess, 43}); err == nil {
t.Errorf("writePacket after botched rekey succeeded.")
}
readback, err := trS.readPacket()
if err != nil {
t.Fatalf("server closed too soon: %v", err)
}
if bytes.Compare(readback, packet) != 0 {
t.Errorf("got %q want %q", readback, packet)
}
readback, err = trS.readPacket()
if err == nil {
t.Errorf("got a message %q after failed key change", readback)
close(checker.called)
if _, ok := <-checker.called; ok {
// If all went well, we registered exactly 2 key changes: one
// that establishes the session, and one that we requested
// additionally.
t.Fatalf("got another host key checks after 2 handshakes")
}
}
func TestForceFirstKex(t *testing.T) {
// like handshakePair, but must access the keyingTransport.
checker := &testChecker{}
trC, trS, err := handshakePair(&ClientConfig{HostKeyCallback: checker.Check}, "addr")
clientConf := &ClientConfig{HostKeyCallback: checker.Check}
a, b, err := netPipe()
if err != nil {
t.Fatalf("handshakePair: %v", err)
t.Fatalf("netPipe: %v", err)
}
defer trC.Close()
defer trS.Close()
var trC, trS keyingTransport
trC = newTransport(a, rand.Reader, true)
// This is the disallowed packet:
trC.writePacket(Marshal(&serviceRequestMsg{serviceUserAuth}))
// Rest of the setup.
trS = newTransport(b, rand.Reader, false)
clientConf.SetDefaults()
v := []byte("version")
client := newClientTransport(trC, v, v, clientConf, "addr", a.RemoteAddr())
serverConf := &ServerConfig{}
serverConf.AddHostKey(testSigners["ecdsa"])
serverConf.AddHostKey(testSigners["rsa"])
serverConf.SetDefaults()
server := newServerTransport(trS, v, v, serverConf)
defer client.Close()
defer server.Close()
// We setup the initial key exchange, but the remote side
// tries to send serviceRequestMsg in cleartext, which is
// disallowed.
err = trS.sendKexInit(firstKeyExchange)
if err == nil {
if err := server.waitSession(); err == nil {
t.Errorf("server first kex init should reject unexpected packet")
}
}
func TestHandshakeTwice(t *testing.T) {
checker := &testChecker{}
trC, trS, err := handshakePair(&ClientConfig{HostKeyCallback: checker.Check}, "addr")
if err != nil {
t.Fatalf("handshakePair: %v", err)
}
defer trC.Close()
defer trS.Close()
// Both sides should ask for the first key exchange first.
err = trS.sendKexInit(firstKeyExchange)
if err != nil {
t.Errorf("server sendKexInit: %v", err)
}
err = trC.sendKexInit(firstKeyExchange)
if err != nil {
t.Errorf("client sendKexInit: %v", err)
}
sent := 0
// send a packet
packet := make([]byte, 5)
packet[0] = msgRequestSuccess
if err := trC.writePacket(packet); err != nil {
t.Errorf("writePacket: %v", err)
}
sent++
// Send another packet. Use a fresh one, since writePacket destroys.
packet = make([]byte, 5)
packet[0] = msgRequestSuccess
if err := trC.writePacket(packet); err != nil {
t.Errorf("writePacket: %v", err)
}
sent++
// 2nd key change.
err = trC.sendKexInit(subsequentKeyExchange)
if err != nil {
t.Errorf("sendKexInit: %v", err)
}
packet = make([]byte, 5)
packet[0] = msgRequestSuccess
if err := trC.writePacket(packet); err != nil {
t.Errorf("writePacket: %v", err)
}
sent++
packet = make([]byte, 5)
packet[0] = msgRequestSuccess
for i := 0; i < sent; i++ {
msg, err := trS.readPacket()
if err != nil {
t.Fatalf("server closed too soon: %v", err)
}
if bytes.Compare(msg, packet) != 0 {
t.Errorf("packet %d: got %q want %q", i, msg, packet)
}
}
if len(checker.calls) != 2 {
t.Errorf("got %d key changes, want 2", len(checker.calls))
}
}
func TestHandshakeAutoRekeyWrite(t *testing.T) {
checker := &testChecker{}
checker := &syncChecker{
called: make(chan int, 10),
waitCall: nil,
}
clientConf := &ClientConfig{HostKeyCallback: checker.Check}
clientConf.RekeyThreshold = 500
trC, trS, err := handshakePair(clientConf, "addr")
trC, trS, err := handshakePair(clientConf, "addr", false)
if err != nil {
t.Fatalf("handshakePair: %v", err)
}
defer trC.Close()
defer trS.Close()
for i := 0; i < 5; i++ {
packet := make([]byte, 251)
packet[0] = msgRequestSuccess
if err := trC.writePacket(packet); err != nil {
input := make([]byte, 251)
input[0] = msgRequestSuccess
done := make(chan int, 1)
const numPacket = 5
go func() {
defer close(done)
j := 0
for ; j < numPacket; j++ {
if p, err := trS.readPacket(); err != nil {
break
} else if !bytes.Equal(input, p) {
t.Errorf("got packet type %d, want %d", p[0], input[0])
}
}
if j != numPacket {
t.Errorf("got %d, want 5 messages", j)
}
}()
<-checker.called
for i := 0; i < numPacket; i++ {
p := make([]byte, len(input))
copy(p, input)
if err := trC.writePacket(p); err != nil {
t.Errorf("writePacket: %v", err)
}
}
j := 0
for ; j < 5; j++ {
_, err := trS.readPacket()
if err != nil {
break
if i == 2 {
// Make sure the kex is in progress.
<-checker.called
}
}
if j != 5 {
t.Errorf("got %d, want 5 messages", j)
}
if len(checker.calls) != 2 {
t.Errorf("got %d key changes, wanted 2", len(checker.calls))
}
<-done
}
type syncChecker struct {
called chan int
waitCall chan int
called chan int
}
func (t *syncChecker) Check(dialAddr string, addr net.Addr, key PublicKey) error {
t.called <- 1
func (c *syncChecker) Check(dialAddr string, addr net.Addr, key PublicKey) error {
c.called <- 1
if c.waitCall != nil {
<-c.waitCall
}
return nil
}
func TestHandshakeAutoRekeyRead(t *testing.T) {
sync := &syncChecker{make(chan int, 2)}
sync := &syncChecker{
called: make(chan int, 2),
waitCall: nil,
}
clientConf := &ClientConfig{
HostKeyCallback: sync.Check,
}
clientConf.RekeyThreshold = 500
trC, trS, err := handshakePair(clientConf, "addr")
trC, trS, err := handshakePair(clientConf, "addr", false)
if err != nil {
t.Fatalf("handshakePair: %v", err)
}
@ -338,12 +342,19 @@ func TestHandshakeAutoRekeyRead(t *testing.T) {
if err := trS.writePacket(packet); err != nil {
t.Fatalf("writePacket: %v", err)
}
// While we read out the packet, a key change will be
// initiated.
if _, err := trC.readPacket(); err != nil {
t.Fatalf("readPacket(client): %v", err)
}
done := make(chan int, 1)
go func() {
defer close(done)
if _, err := trC.readPacket(); err != nil {
t.Fatalf("readPacket(client): %v", err)
}
}()
<-done
<-sync.called
}
@ -357,6 +368,7 @@ type errorKeyingTransport struct {
func (n *errorKeyingTransport) prepareKeyChange(*algorithms, *kexResult) error {
return nil
}
func (n *errorKeyingTransport) getSessionID() []byte {
return nil
}
@ -383,20 +395,32 @@ func (n *errorKeyingTransport) readPacket() ([]byte, error) {
func TestHandshakeErrorHandlingRead(t *testing.T) {
for i := 0; i < 20; i++ {
testHandshakeErrorHandlingN(t, i, -1)
testHandshakeErrorHandlingN(t, i, -1, false)
}
}
func TestHandshakeErrorHandlingWrite(t *testing.T) {
for i := 0; i < 20; i++ {
testHandshakeErrorHandlingN(t, -1, i)
testHandshakeErrorHandlingN(t, -1, i, false)
}
}
func TestHandshakeErrorHandlingReadCoupled(t *testing.T) {
for i := 0; i < 20; i++ {
testHandshakeErrorHandlingN(t, i, -1, true)
}
}
func TestHandshakeErrorHandlingWriteCoupled(t *testing.T) {
for i := 0; i < 20; i++ {
testHandshakeErrorHandlingN(t, -1, i, true)
}
}
// testHandshakeErrorHandlingN runs handshakes, injecting errors. If
// handshakeTransport deadlocks, the go runtime will detect it and
// panic.
func testHandshakeErrorHandlingN(t *testing.T, readLimit, writeLimit int) {
func testHandshakeErrorHandlingN(t *testing.T, readLimit, writeLimit int, coupled bool) {
msg := Marshal(&serviceRequestMsg{strings.Repeat("x", int(minRekeyThreshold)/4)})
a, b := memPipe()
@ -409,37 +433,58 @@ func testHandshakeErrorHandlingN(t *testing.T, readLimit, writeLimit int) {
serverConn := newHandshakeTransport(&errorKeyingTransport{a, readLimit, writeLimit}, &serverConf, []byte{'a'}, []byte{'b'})
serverConn.hostKeys = []Signer{key}
go serverConn.readLoop()
go serverConn.kexLoop()
clientConf := Config{RekeyThreshold: 10 * minRekeyThreshold}
clientConf.SetDefaults()
clientConn := newHandshakeTransport(&errorKeyingTransport{b, -1, -1}, &clientConf, []byte{'a'}, []byte{'b'})
clientConn.hostKeyAlgorithms = []string{key.PublicKey().Type()}
clientConn.hostKeyCallback = InsecureIgnoreHostKey()
go clientConn.readLoop()
go clientConn.kexLoop()
var wg sync.WaitGroup
wg.Add(4)
for _, hs := range []packetConn{serverConn, clientConn} {
go func(c packetConn) {
for {
err := c.writePacket(msg)
if err != nil {
break
if !coupled {
wg.Add(2)
go func(c packetConn) {
for i := 0; ; i++ {
str := fmt.Sprintf("%08x", i) + strings.Repeat("x", int(minRekeyThreshold)/4-8)
err := c.writePacket(Marshal(&serviceRequestMsg{str}))
if err != nil {
break
}
}
}
wg.Done()
}(hs)
go func(c packetConn) {
for {
_, err := c.readPacket()
if err != nil {
break
wg.Done()
c.Close()
}(hs)
go func(c packetConn) {
for {
_, err := c.readPacket()
if err != nil {
break
}
}
}
wg.Done()
}(hs)
}
wg.Done()
}(hs)
} else {
wg.Add(1)
go func(c packetConn) {
for {
_, err := c.readPacket()
if err != nil {
break
}
if err := c.writePacket(msg); err != nil {
break
}
}
wg.Done()
}(hs)
}
}
wg.Wait()
}
@ -448,7 +493,7 @@ func TestDisconnect(t *testing.T) {
t.Skip("see golang.org/issue/7237")
}
checker := &testChecker{}
trC, trS, err := handshakePair(&ClientConfig{HostKeyCallback: checker.Check}, "addr")
trC, trS, err := handshakePair(&ClientConfig{HostKeyCallback: checker.Check}, "addr", false)
if err != nil {
t.Fatalf("handshakePair: %v", err)
}
@ -484,3 +529,31 @@ func TestDisconnect(t *testing.T) {
t.Errorf("readPacket 3 succeeded")
}
}
func TestHandshakeRekeyDefault(t *testing.T) {
clientConf := &ClientConfig{
Config: Config{
Ciphers: []string{"aes128-ctr"},
},
HostKeyCallback: InsecureIgnoreHostKey(),
}
trC, trS, err := handshakePair(clientConf, "addr", false)
if err != nil {
t.Fatalf("handshakePair: %v", err)
}
defer trC.Close()
defer trS.Close()
trC.writePacket([]byte{msgRequestSuccess, 0, 0})
trC.Close()
rgb := (1024 + trC.readBytesLeft) >> 30
wgb := (1024 + trC.writeBytesLeft) >> 30
if rgb != 64 {
t.Errorf("got rekey after %dG read, want 64G", rgb)
}
if wgb != 64 {
t.Errorf("got rekey after %dG write, want 64G", wgb)
}
}

38
ssh/kex.go
View file

@ -77,11 +77,11 @@ type kexAlgorithm interface {
// dhGroup is a multiplicative group suitable for implementing Diffie-Hellman key agreement.
type dhGroup struct {
g, p *big.Int
g, p, pMinus1 *big.Int
}
func (group *dhGroup) diffieHellman(theirPublic, myPrivate *big.Int) (*big.Int, error) {
if theirPublic.Sign() <= 0 || theirPublic.Cmp(group.p) >= 0 {
if theirPublic.Cmp(bigOne) <= 0 || theirPublic.Cmp(group.pMinus1) >= 0 {
return nil, errors.New("ssh: DH parameter out of bounds")
}
return new(big.Int).Exp(theirPublic, myPrivate, group.p), nil
@ -90,10 +90,17 @@ func (group *dhGroup) diffieHellman(theirPublic, myPrivate *big.Int) (*big.Int,
func (group *dhGroup) Client(c packetConn, randSource io.Reader, magics *handshakeMagics) (*kexResult, error) {
hashFunc := crypto.SHA1
x, err := rand.Int(randSource, group.p)
if err != nil {
return nil, err
var x *big.Int
for {
var err error
if x, err = rand.Int(randSource, group.pMinus1); err != nil {
return nil, err
}
if x.Sign() > 0 {
break
}
}
X := new(big.Int).Exp(group.g, x, group.p)
kexDHInit := kexDHInitMsg{
X: X,
@ -146,9 +153,14 @@ func (group *dhGroup) Server(c packetConn, randSource io.Reader, magics *handsha
return
}
y, err := rand.Int(randSource, group.p)
if err != nil {
return
var y *big.Int
for {
if y, err = rand.Int(randSource, group.pMinus1); err != nil {
return
}
if y.Sign() > 0 {
break
}
}
Y := new(big.Int).Exp(group.g, y, group.p)
@ -371,8 +383,9 @@ func init() {
// 4253 and Oakley Group 2 in RFC 2409.
p, _ := new(big.Int).SetString("FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF", 16)
kexAlgoMap[kexAlgoDH1SHA1] = &dhGroup{
g: new(big.Int).SetInt64(2),
p: p,
g: new(big.Int).SetInt64(2),
p: p,
pMinus1: new(big.Int).Sub(p, bigOne),
}
// This is the group called diffie-hellman-group14-sha1 in RFC
@ -380,8 +393,9 @@ func init() {
p, _ = new(big.Int).SetString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
kexAlgoMap[kexAlgoDH14SHA1] = &dhGroup{
g: new(big.Int).SetInt64(2),
p: p,
g: new(big.Int).SetInt64(2),
p: p,
pMinus1: new(big.Int).Sub(p, bigOne),
}
kexAlgoMap[kexAlgoECDH521] = &ecdh{elliptic.P521()}

206
ssh/keys.go
View file

@ -10,10 +10,13 @@ import (
"crypto/dsa"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/md5"
"crypto/rsa"
"crypto/sha256"
"crypto/x509"
"encoding/asn1"
"encoding/base64"
"encoding/hex"
"encoding/pem"
"errors"
"fmt"
@ -281,6 +284,12 @@ type PublicKey interface {
Verify(data []byte, sig *Signature) error
}
// CryptoPublicKey, if implemented by a PublicKey,
// returns the underlying crypto.PublicKey form of the key.
type CryptoPublicKey interface {
CryptoPublicKey() crypto.PublicKey
}
// A Signer can create signatures that verify against a public key.
type Signer interface {
// PublicKey returns an associated PublicKey instance.
@ -348,6 +357,10 @@ func (r *rsaPublicKey) Verify(data []byte, sig *Signature) error {
return rsa.VerifyPKCS1v15((*rsa.PublicKey)(r), crypto.SHA1, digest, sig.Blob)
}
func (r *rsaPublicKey) CryptoPublicKey() crypto.PublicKey {
return (*rsa.PublicKey)(r)
}
type dsaPublicKey dsa.PublicKey
func (r *dsaPublicKey) Type() string {
@ -416,6 +429,10 @@ func (k *dsaPublicKey) Verify(data []byte, sig *Signature) error {
return errors.New("ssh: signature did not verify")
}
func (k *dsaPublicKey) CryptoPublicKey() crypto.PublicKey {
return (*dsa.PublicKey)(k)
}
type dsaPrivateKey struct {
*dsa.PrivateKey
}
@ -509,6 +526,10 @@ func (key ed25519PublicKey) Verify(b []byte, sig *Signature) error {
return nil
}
func (k ed25519PublicKey) CryptoPublicKey() crypto.PublicKey {
return ed25519.PublicKey(k)
}
func supportedEllipticCurve(curve elliptic.Curve) bool {
return curve == elliptic.P256() || curve == elliptic.P384() || curve == elliptic.P521()
}
@ -604,6 +625,10 @@ func (key *ecdsaPublicKey) Verify(data []byte, sig *Signature) error {
return errors.New("ssh: signature did not verify")
}
func (k *ecdsaPublicKey) CryptoPublicKey() crypto.PublicKey {
return (*ecdsa.PublicKey)(k)
}
// NewSignerFromKey takes an *rsa.PrivateKey, *dsa.PrivateKey,
// *ecdsa.PrivateKey or any other crypto.Signer and returns a corresponding
// Signer instance. ECDSA keys must use P-256, P-384 or P-521.
@ -700,8 +725,8 @@ func (s *wrappedSigner) Sign(rand io.Reader, data []byte) (*Signature, error) {
}
// NewPublicKey takes an *rsa.PublicKey, *dsa.PublicKey, *ecdsa.PublicKey,
// ed25519.PublicKey, or any other crypto.Signer and returns a corresponding
// Signer instance. ECDSA keys must use P-256, P-384 or P-521.
// or ed25519.PublicKey returns a corresponding PublicKey instance.
// ECDSA keys must use P-256, P-384 or P-521.
func NewPublicKey(key interface{}) (PublicKey, error) {
switch key := key.(type) {
case *rsa.PublicKey:
@ -731,6 +756,26 @@ func ParsePrivateKey(pemBytes []byte) (Signer, error) {
return NewSignerFromKey(key)
}
// ParsePrivateKeyWithPassphrase returns a Signer from a PEM encoded private
// key and passphrase. It supports the same keys as
// ParseRawPrivateKeyWithPassphrase.
func ParsePrivateKeyWithPassphrase(pemBytes, passPhrase []byte) (Signer, error) {
key, err := ParseRawPrivateKeyWithPassphrase(pemBytes, passPhrase)
if err != nil {
return nil, err
}
return NewSignerFromKey(key)
}
// encryptedBlock tells whether a private key is
// encrypted by examining its Proc-Type header
// for a mention of ENCRYPTED
// according to RFC 1421 Section 4.6.1.1.
func encryptedBlock(block *pem.Block) bool {
return strings.Contains(block.Headers["Proc-Type"], "ENCRYPTED")
}
// ParseRawPrivateKey returns a private key from a PEM encoded private key. It
// supports RSA (PKCS#1), DSA (OpenSSL), and ECDSA private keys.
func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
@ -739,6 +784,10 @@ func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
return nil, errors.New("ssh: no key found")
}
if encryptedBlock(block) {
return nil, errors.New("ssh: cannot decode encrypted private keys")
}
switch block.Type {
case "RSA PRIVATE KEY":
return x509.ParsePKCS1PrivateKey(block.Bytes)
@ -753,6 +802,37 @@ func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
}
}
func ParseRawPrivateKeyWithPassphrase(pemBytes, passPhrase []byte) (interface{}, error) {
block, _ := pem.Decode(pemBytes)
if block == nil {
return nil, errors.New("ssh: no key found")
}
buf := block.Bytes
if encryptedBlock(block) {
if x509.IsEncryptedPEMBlock(block) {
var err error
buf, err = x509.DecryptPEMBlock(block, passPhrase)
if err != nil {
return nil, fmt.Errorf("ssh: cannot decode encrypted private keys: %v", err)
}
}
}
switch block.Type {
case "RSA PRIVATE KEY":
return x509.ParsePKCS1PrivateKey(buf)
case "EC PRIVATE KEY":
return x509.ParseECPrivateKey(buf)
case "DSA PRIVATE KEY":
return ParseDSAPrivateKey(buf)
case "OPENSSH PRIVATE KEY":
return parseOpenSSHPrivateKey(buf)
default:
return nil, fmt.Errorf("ssh: unsupported key type %q", block.Type)
}
}
// ParseDSAPrivateKey returns a DSA private key from its ASN.1 DER encoding, as
// specified by the OpenSSL DSA man page.
func ParseDSAPrivateKey(der []byte) (*dsa.PrivateKey, error) {
@ -761,8 +841,8 @@ func ParseDSAPrivateKey(der []byte) (*dsa.PrivateKey, error) {
P *big.Int
Q *big.Int
G *big.Int
Priv *big.Int
Pub *big.Int
Priv *big.Int
}
rest, err := asn1.Unmarshal(der, &k)
if err != nil {
@ -779,15 +859,15 @@ func ParseDSAPrivateKey(der []byte) (*dsa.PrivateKey, error) {
Q: k.Q,
G: k.G,
},
Y: k.Priv,
Y: k.Pub,
},
X: k.Pub,
X: k.Priv,
}, nil
}
// Implemented based on the documentation at
// https://github.com/openssh/openssh-portable/blob/master/PROTOCOL.key
func parseOpenSSHPrivateKey(key []byte) (*ed25519.PrivateKey, error) {
func parseOpenSSHPrivateKey(key []byte) (crypto.PrivateKey, error) {
magic := append([]byte("openssh-key-v1"), 0)
if !bytes.Equal(magic, key[0:len(magic)]) {
return nil, errors.New("ssh: invalid openssh private key format")
@ -807,14 +887,15 @@ func parseOpenSSHPrivateKey(key []byte) (*ed25519.PrivateKey, error) {
return nil, err
}
if w.KdfName != "none" || w.CipherName != "none" {
return nil, errors.New("ssh: cannot decode encrypted private keys")
}
pk1 := struct {
Check1 uint32
Check2 uint32
Keytype string
Pub []byte
Priv []byte
Comment string
Pad []byte `ssh:"rest"`
Rest []byte `ssh:"rest"`
}{}
if err := Unmarshal(w.PrivKeyBlock, &pk1); err != nil {
@ -825,22 +906,95 @@ func parseOpenSSHPrivateKey(key []byte) (*ed25519.PrivateKey, error) {
return nil, errors.New("ssh: checkint mismatch")
}
// we only handle ed25519 keys currently
if pk1.Keytype != KeyAlgoED25519 {
// we only handle ed25519 and rsa keys currently
switch pk1.Keytype {
case KeyAlgoRSA:
// https://github.com/openssh/openssh-portable/blob/master/sshkey.c#L2760-L2773
key := struct {
N *big.Int
E *big.Int
D *big.Int
Iqmp *big.Int
P *big.Int
Q *big.Int
Comment string
Pad []byte `ssh:"rest"`
}{}
if err := Unmarshal(pk1.Rest, &key); err != nil {
return nil, err
}
for i, b := range key.Pad {
if int(b) != i+1 {
return nil, errors.New("ssh: padding not as expected")
}
}
pk := &rsa.PrivateKey{
PublicKey: rsa.PublicKey{
N: key.N,
E: int(key.E.Int64()),
},
D: key.D,
Primes: []*big.Int{key.P, key.Q},
}
if err := pk.Validate(); err != nil {
return nil, err
}
pk.Precompute()
return pk, nil
case KeyAlgoED25519:
key := struct {
Pub []byte
Priv []byte
Comment string
Pad []byte `ssh:"rest"`
}{}
if err := Unmarshal(pk1.Rest, &key); err != nil {
return nil, err
}
if len(key.Priv) != ed25519.PrivateKeySize {
return nil, errors.New("ssh: private key unexpected length")
}
for i, b := range key.Pad {
if int(b) != i+1 {
return nil, errors.New("ssh: padding not as expected")
}
}
pk := ed25519.PrivateKey(make([]byte, ed25519.PrivateKeySize))
copy(pk, key.Priv)
return &pk, nil
default:
return nil, errors.New("ssh: unhandled key type")
}
for i, b := range pk1.Pad {
if int(b) != i+1 {
return nil, errors.New("ssh: padding not as expected")
}
}
if len(pk1.Priv) != ed25519.PrivateKeySize {
return nil, errors.New("ssh: private key unexpected length")
}
pk := ed25519.PrivateKey(make([]byte, ed25519.PrivateKeySize))
copy(pk, pk1.Priv)
return &pk, nil
}
// FingerprintLegacyMD5 returns the user presentation of the key's
// fingerprint as described by RFC 4716 section 4.
func FingerprintLegacyMD5(pubKey PublicKey) string {
md5sum := md5.Sum(pubKey.Marshal())
hexarray := make([]string, len(md5sum))
for i, c := range md5sum {
hexarray[i] = hex.EncodeToString([]byte{c})
}
return strings.Join(hexarray, ":")
}
// FingerprintSHA256 returns the user presentation of the key's
// fingerprint as unpadded base64 encoded sha256 hash.
// This format was introduced from OpenSSH 6.8.
// https://www.openssh.com/txt/release-6.8
// https://tools.ietf.org/html/rfc4648#section-3.2 (unpadded base64 encoding)
func FingerprintSHA256(pubKey PublicKey) string {
sha256sum := sha256.Sum256(pubKey.Marshal())
hash := base64.RawStdEncoding.EncodeToString(sha256sum[:])
return "SHA256:" + hash
}

71
ssh/keys_test.go
View file

@ -132,6 +132,41 @@ func TestParseECPrivateKey(t *testing.T) {
}
}
// See Issue https://github.com/golang/go/issues/6650.
func TestParseEncryptedPrivateKeysFails(t *testing.T) {
const wantSubstring = "encrypted"
for i, tt := range testdata.PEMEncryptedKeys {
_, err := ParsePrivateKey(tt.PEMBytes)
if err == nil {
t.Errorf("#%d key %s: ParsePrivateKey successfully parsed, expected an error", i, tt.Name)
continue
}
if !strings.Contains(err.Error(), wantSubstring) {
t.Errorf("#%d key %s: got error %q, want substring %q", i, tt.Name, err, wantSubstring)
}
}
}
// Parse encrypted private keys with passphrase
func TestParseEncryptedPrivateKeysWithPassphrase(t *testing.T) {
data := []byte("sign me")
for _, tt := range testdata.PEMEncryptedKeys {
s, err := ParsePrivateKeyWithPassphrase(tt.PEMBytes, []byte(tt.EncryptionKey))
if err != nil {
t.Fatalf("ParsePrivateKeyWithPassphrase returned error: %s", err)
continue
}
sig, err := s.Sign(rand.Reader, data)
if err != nil {
t.Fatalf("dsa.Sign: %v", err)
}
if err := s.PublicKey().Verify(data, sig); err != nil {
t.Errorf("Verify failed: %v", err)
}
}
}
func TestParseDSA(t *testing.T) {
// We actually exercise the ParsePrivateKey codepath here, as opposed to
// using the ParseRawPrivateKey+NewSignerFromKey path that testdata_test.go
@ -309,14 +344,14 @@ func TestInvalidEntry(t *testing.T) {
}
var knownHostsParseTests = []struct {
input string
err string
input string
err string
marker string
comment string
hosts []string
rest string
} {
marker string
comment string
hosts []string
rest string
}{
{
"",
"EOF",
@ -375,13 +410,13 @@ var knownHostsParseTests = []struct {
"localhost,[host2:123]\tssh-rsa {RSAPUB}\tcomment comment",
"",
"", "comment comment", []string{"localhost","[host2:123]"}, "",
"", "comment comment", []string{"localhost", "[host2:123]"}, "",
},
{
"@marker \tlocalhost,[host2:123]\tssh-rsa {RSAPUB}",
"",
"marker", "", []string{"localhost","[host2:123]"}, "",
"marker", "", []string{"localhost", "[host2:123]"}, "",
},
{
"@marker \tlocalhost,[host2:123]\tssh-rsa aabbccdd",
@ -438,3 +473,21 @@ func TestKnownHostsParsing(t *testing.T) {
}
}
}
func TestFingerprintLegacyMD5(t *testing.T) {
pub, _ := getTestKey()
fingerprint := FingerprintLegacyMD5(pub)
want := "fb:61:6d:1a:e3:f0:95:45:3c:a0:79:be:4a:93:63:66" // ssh-keygen -lf -E md5 rsa
if fingerprint != want {
t.Errorf("got fingerprint %q want %q", fingerprint, want)
}
}
func TestFingerprintSHA256(t *testing.T) {
pub, _ := getTestKey()
fingerprint := FingerprintSHA256(pub)
want := "SHA256:Anr3LjZK8YVpjrxu79myrW9Hrb/wpcMNpVvTq/RcBm8" // ssh-keygen -lf rsa
if fingerprint != want {
t.Errorf("got fingerprint %q want %q", fingerprint, want)
}
}

546
ssh/knownhosts/knownhosts.go Normal file
View file

@ -0,0 +1,546 @@
// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package knownhosts implements a parser for the OpenSSH
// known_hosts host key database.
package knownhosts
import (
"bufio"
"bytes"
"crypto/hmac"
"crypto/rand"
"crypto/sha1"
"encoding/base64"
"errors"
"fmt"
"io"
"net"
"os"
"strings"
"golang.org/x/crypto/ssh"
)
// See the sshd manpage
// (http://man.openbsd.org/sshd#SSH_KNOWN_HOSTS_FILE_FORMAT) for
// background.
type addr struct{ host, port string }
func (a *addr) String() string {
h := a.host
if strings.Contains(h, ":") {
h = "[" + h + "]"
}
return h + ":" + a.port
}
type matcher interface {
match([]addr) bool
}
type hostPattern struct {
negate bool
addr addr
}
func (p *hostPattern) String() string {
n := ""
if p.negate {
n = "!"
}
return n + p.addr.String()
}
type hostPatterns []hostPattern
func (ps hostPatterns) match(addrs []addr) bool {
matched := false
for _, p := range ps {
for _, a := range addrs {
m := p.match(a)
if !m {
continue
}
if p.negate {
return false
}
matched = true
}
}
return matched
}
// See
// https://android.googlesource.com/platform/external/openssh/+/ab28f5495c85297e7a597c1ba62e996416da7c7e/addrmatch.c
// The matching of * has no regard for separators, unlike filesystem globs
func wildcardMatch(pat []byte, str []byte) bool {
for {
if len(pat) == 0 {
return len(str) == 0
}
if len(str) == 0 {
return false
}
if pat[0] == '*' {
if len(pat) == 1 {
return true
}
for j := range str {
if wildcardMatch(pat[1:], str[j:]) {
return true
}
}
return false
}
if pat[0] == '?' || pat[0] == str[0] {
pat = pat[1:]
str = str[1:]
} else {
return false
}
}
}
func (l *hostPattern) match(a addr) bool {
return wildcardMatch([]byte(l.addr.host), []byte(a.host)) && l.addr.port == a.port
}
type keyDBLine struct {
cert bool
matcher matcher
knownKey KnownKey
}
func serialize(k ssh.PublicKey) string {
return k.Type() + " " + base64.StdEncoding.EncodeToString(k.Marshal())
}
func (l *keyDBLine) match(addrs []addr) bool {
return l.matcher.match(addrs)
}
type hostKeyDB struct {
// Serialized version of revoked keys
revoked map[string]*KnownKey
lines []keyDBLine
}
func newHostKeyDB() *hostKeyDB {
db := &hostKeyDB{
revoked: make(map[string]*KnownKey),
}
return db
}
func keyEq(a, b ssh.PublicKey) bool {
return bytes.Equal(a.Marshal(), b.Marshal())
}
// IsAuthorityForHost can be used as a callback in ssh.CertChecker
func (db *hostKeyDB) IsHostAuthority(remote ssh.PublicKey, address string) bool {
h, p, err := net.SplitHostPort(address)
if err != nil {
return false
}
a := addr{host: h, port: p}
for _, l := range db.lines {
if l.cert && keyEq(l.knownKey.Key, remote) && l.match([]addr{a}) {
return true
}
}
return false
}
// IsRevoked can be used as a callback in ssh.CertChecker
func (db *hostKeyDB) IsRevoked(key *ssh.Certificate) bool {
_, ok := db.revoked[string(key.Marshal())]
return ok
}
const markerCert = "@cert-authority"
const markerRevoked = "@revoked"
func nextWord(line []byte) (string, []byte) {
i := bytes.IndexAny(line, "\t ")
if i == -1 {
return string(line), nil
}
return string(line[:i]), bytes.TrimSpace(line[i:])
}
func parseLine(line []byte) (marker, host string, key ssh.PublicKey, err error) {
if w, next := nextWord(line); w == markerCert || w == markerRevoked {
marker = w
line = next
}
host, line = nextWord(line)
if len(line) == 0 {
return "", "", nil, errors.New("knownhosts: missing host pattern")
}
// ignore the keytype as it's in the key blob anyway.
_, line = nextWord(line)
if len(line) == 0 {
return "", "", nil, errors.New("knownhosts: missing key type pattern")
}
keyBlob, _ := nextWord(line)
keyBytes, err := base64.StdEncoding.DecodeString(keyBlob)
if err != nil {
return "", "", nil, err
}
key, err = ssh.ParsePublicKey(keyBytes)
if err != nil {
return "", "", nil, err
}
return marker, host, key, nil
}
func (db *hostKeyDB) parseLine(line []byte, filename string, linenum int) error {
marker, pattern, key, err := parseLine(line)
if err != nil {
return err
}
if marker == markerRevoked {
db.revoked[string(key.Marshal())] = &KnownKey{
Key: key,
Filename: filename,
Line: linenum,
}
return nil
}
entry := keyDBLine{
cert: marker == markerCert,
knownKey: KnownKey{
Filename: filename,
Line: linenum,
Key: key,
},
}
if pattern[0] == '|' {
entry.matcher, err = newHashedHost(pattern)
} else {
entry.matcher, err = newHostnameMatcher(pattern)
}
if err != nil {
return err
}
db.lines = append(db.lines, entry)
return nil
}
func newHostnameMatcher(pattern string) (matcher, error) {
var hps hostPatterns
for _, p := range strings.Split(pattern, ",") {
if len(p) == 0 {
continue
}
var a addr
var negate bool
if p[0] == '!' {
negate = true
p = p[1:]
}
if len(p) == 0 {
return nil, errors.New("knownhosts: negation without following hostname")
}
var err error
if p[0] == '[' {
a.host, a.port, err = net.SplitHostPort(p)
if err != nil {
return nil, err
}
} else {
a.host, a.port, err = net.SplitHostPort(p)
if err != nil {
a.host = p
a.port = "22"
}
}
hps = append(hps, hostPattern{
negate: negate,
addr: a,
})
}
return hps, nil
}
// KnownKey represents a key declared in a known_hosts file.
type KnownKey struct {
Key ssh.PublicKey
Filename string
Line int
}
func (k *KnownKey) String() string {
return fmt.Sprintf("%s:%d: %s", k.Filename, k.Line, serialize(k.Key))
}
// KeyError is returned if we did not find the key in the host key
// database, or there was a mismatch. Typically, in batch
// applications, this should be interpreted as failure. Interactive
// applications can offer an interactive prompt to the user.
type KeyError struct {
// Want holds the accepted host keys. For each key algorithm,
// there can be one hostkey. If Want is empty, the host is
// unknown. If Want is non-empty, there was a mismatch, which
// can signify a MITM attack.
Want []KnownKey
}
func (u *KeyError) Error() string {
if len(u.Want) == 0 {
return "knownhosts: key is unknown"
}
return "knownhosts: key mismatch"
}
// RevokedError is returned if we found a key that was revoked.
type RevokedError struct {
Revoked KnownKey
}
func (r *RevokedError) Error() string {
return "knownhosts: key is revoked"
}
// check checks a key against the host database. This should not be
// used for verifying certificates.
func (db *hostKeyDB) check(address string, remote net.Addr, remoteKey ssh.PublicKey) error {
if revoked := db.revoked[string(remoteKey.Marshal())]; revoked != nil {
return &RevokedError{Revoked: *revoked}
}
host, port, err := net.SplitHostPort(remote.String())
if err != nil {
return fmt.Errorf("knownhosts: SplitHostPort(%s): %v", remote, err)
}
addrs := []addr{
{host, port},
}
if address != "" {
host, port, err := net.SplitHostPort(address)
if err != nil {
return fmt.Errorf("knownhosts: SplitHostPort(%s): %v", address, err)
}
addrs = append(addrs, addr{host, port})
}
return db.checkAddrs(addrs, remoteKey)
}
// checkAddrs checks if we can find the given public key for any of
// the given addresses. If we only find an entry for the IP address,
// or only the hostname, then this still succeeds.
func (db *hostKeyDB) checkAddrs(addrs []addr, remoteKey ssh.PublicKey) error {
// TODO(hanwen): are these the right semantics? What if there
// is just a key for the IP address, but not for the
// hostname?
// Algorithm => key.
knownKeys := map[string]KnownKey{}
for _, l := range db.lines {
if l.match(addrs) {
typ := l.knownKey.Key.Type()
if _, ok := knownKeys[typ]; !ok {
knownKeys[typ] = l.knownKey
}
}
}
keyErr := &KeyError{}
for _, v := range knownKeys {
keyErr.Want = append(keyErr.Want, v)
}
// Unknown remote host.
if len(knownKeys) == 0 {
return keyErr
}
// If the remote host starts using a different, unknown key type, we
// also interpret that as a mismatch.
if known, ok := knownKeys[remoteKey.Type()]; !ok || !keyEq(known.Key, remoteKey) {
return keyErr
}
return nil
}
// The Read function parses file contents.
func (db *hostKeyDB) Read(r io.Reader, filename string) error {
scanner := bufio.NewScanner(r)
lineNum := 0
for scanner.Scan() {
lineNum++
line := scanner.Bytes()
line = bytes.TrimSpace(line)
if len(line) == 0 || line[0] == '#' {
continue
}
if err := db.parseLine(line, filename, lineNum); err != nil {
return fmt.Errorf("knownhosts: %s:%d: %v", filename, lineNum, err)
}
}
return scanner.Err()
}
// New creates a host key callback from the given OpenSSH host key
// files. The returned callback is for use in
// ssh.ClientConfig.HostKeyCallback. Hashed hostnames are not supported.
func New(files ...string) (ssh.HostKeyCallback, error) {
db := newHostKeyDB()
for _, fn := range files {
f, err := os.Open(fn)
if err != nil {
return nil, err
}
defer f.Close()
if err := db.Read(f, fn); err != nil {
return nil, err
}
}
var certChecker ssh.CertChecker
certChecker.IsHostAuthority = db.IsHostAuthority
certChecker.IsRevoked = db.IsRevoked
certChecker.HostKeyFallback = db.check
return certChecker.CheckHostKey, nil
}
// Normalize normalizes an address into the form used in known_hosts
func Normalize(address string) string {
host, port, err := net.SplitHostPort(address)
if err != nil {
host = address
port = "22"
}
entry := host
if port != "22" {
entry = "[" + entry + "]:" + port
} else if strings.Contains(host, ":") && !strings.HasPrefix(host, "[") {
entry = "[" + entry + "]"
}
return entry
}
// Line returns a line to add append to the known_hosts files.
func Line(addresses []string, key ssh.PublicKey) string {
var trimmed []string
for _, a := range addresses {
trimmed = append(trimmed, Normalize(a))
}
return strings.Join(trimmed, ",") + " " + serialize(key)
}
// HashHostname hashes the given hostname. The hostname is not
// normalized before hashing.
func HashHostname(hostname string) string {
// TODO(hanwen): check if we can safely normalize this always.
salt := make([]byte, sha1.Size)
_, err := rand.Read(salt)
if err != nil {
panic(fmt.Sprintf("crypto/rand failure %v", err))
}
hash := hashHost(hostname, salt)
return encodeHash(sha1HashType, salt, hash)
}
func decodeHash(encoded string) (hashType string, salt, hash []byte, err error) {
if len(encoded) == 0 || encoded[0] != '|' {
err = errors.New("knownhosts: hashed host must start with '|'")
return
}
components := strings.Split(encoded, "|")
if len(components) != 4 {
err = fmt.Errorf("knownhosts: got %d components, want 3", len(components))
return
}
hashType = components[1]
if salt, err = base64.StdEncoding.DecodeString(components[2]); err != nil {
return
}
if hash, err = base64.StdEncoding.DecodeString(components[3]); err != nil {
return
}
return
}
func encodeHash(typ string, salt []byte, hash []byte) string {
return strings.Join([]string{"",
typ,
base64.StdEncoding.EncodeToString(salt),
base64.StdEncoding.EncodeToString(hash),
}, "|")
}
// See https://android.googlesource.com/platform/external/openssh/+/ab28f5495c85297e7a597c1ba62e996416da7c7e/hostfile.c#120
func hashHost(hostname string, salt []byte) []byte {
mac := hmac.New(sha1.New, salt)
mac.Write([]byte(hostname))
return mac.Sum(nil)
}
type hashedHost struct {
salt []byte
hash []byte
}
const sha1HashType = "1"
func newHashedHost(encoded string) (*hashedHost, error) {
typ, salt, hash, err := decodeHash(encoded)
if err != nil {
return nil, err
}
// The type field seems for future algorithm agility, but it's
// actually hardcoded in openssh currently, see
// https://android.googlesource.com/platform/external/openssh/+/ab28f5495c85297e7a597c1ba62e996416da7c7e/hostfile.c#120
if typ != sha1HashType {
return nil, fmt.Errorf("knownhosts: got hash type %s, must be '1'", typ)
}
return &hashedHost{salt: salt, hash: hash}, nil
}
func (h *hashedHost) match(addrs []addr) bool {
for _, a := range addrs {
if bytes.Equal(hashHost(Normalize(a.String()), h.salt), h.hash) {
return true
}
}
return false
}

329
ssh/knownhosts/knownhosts_test.go Normal file
View file

@ -0,0 +1,329 @@
// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package knownhosts
import (
"bytes"
"fmt"
"net"
"reflect"
"testing"
"golang.org/x/crypto/ssh"
)
const edKeyStr = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGBAarftlLeoyf+v+nVchEZII/vna2PCV8FaX4vsF5BX"
const alternateEdKeyStr = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIXffBYeYL+WVzVru8npl5JHt2cjlr4ornFTWzoij9sx"
const ecKeyStr = "ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBNLCu01+wpXe3xB5olXCN4SqU2rQu0qjSRKJO4Bg+JRCPU+ENcgdA5srTU8xYDz/GEa4dzK5ldPw4J/gZgSXCMs="
var ecKey, alternateEdKey, edKey ssh.PublicKey
var testAddr = &net.TCPAddr{
IP: net.IP{198, 41, 30, 196},
Port: 22,
}
var testAddr6 = &net.TCPAddr{
IP: net.IP{198, 41, 30, 196,
1, 2, 3, 4,
1, 2, 3, 4,
1, 2, 3, 4,
},
Port: 22,
}
func init() {
var err error
ecKey, _, _, _, err = ssh.ParseAuthorizedKey([]byte(ecKeyStr))
if err != nil {
panic(err)
}
edKey, _, _, _, err = ssh.ParseAuthorizedKey([]byte(edKeyStr))
if err != nil {
panic(err)
}
alternateEdKey, _, _, _, err = ssh.ParseAuthorizedKey([]byte(alternateEdKeyStr))
if err != nil {
panic(err)
}
}
func testDB(t *testing.T, s string) *hostKeyDB {
db := newHostKeyDB()
if err := db.Read(bytes.NewBufferString(s), "testdb"); err != nil {
t.Fatalf("Read: %v", err)
}
return db
}
func TestRevoked(t *testing.T) {
db := testDB(t, "\n\n@revoked * "+edKeyStr+"\n")
want := &RevokedError{
Revoked: KnownKey{
Key: edKey,
Filename: "testdb",
Line: 3,
},
}
if err := db.check("", &net.TCPAddr{
Port: 42,
}, edKey); err == nil {
t.Fatal("no error for revoked key")
} else if !reflect.DeepEqual(want, err) {
t.Fatalf("got %#v, want %#v", want, err)
}
}
func TestHostAuthority(t *testing.T) {
for _, m := range []struct {
authorityFor string
address string
good bool
}{
{authorityFor: "localhost", address: "localhost:22", good: true},
{authorityFor: "localhost", address: "localhost", good: false},
{authorityFor: "localhost", address: "localhost:1234", good: false},
{authorityFor: "[localhost]:1234", address: "localhost:1234", good: true},
{authorityFor: "[localhost]:1234", address: "localhost:22", good: false},
{authorityFor: "[localhost]:1234", address: "localhost", good: false},
} {
db := testDB(t, `@cert-authority `+m.authorityFor+` `+edKeyStr)
if ok := db.IsHostAuthority(db.lines[0].knownKey.Key, m.address); ok != m.good {
t.Errorf("IsHostAuthority: authority %s, address %s, wanted good = %v, got good = %v",
m.authorityFor, m.address, m.good, ok)
}
}
}
func TestBracket(t *testing.T) {
db := testDB(t, `[git.eclipse.org]:29418,[198.41.30.196]:29418 `+edKeyStr)
if err := db.check("git.eclipse.org:29418", &net.TCPAddr{
IP: net.IP{198, 41, 30, 196},
Port: 29418,
}, edKey); err != nil {
t.Errorf("got error %v, want none", err)
}
if err := db.check("git.eclipse.org:29419", &net.TCPAddr{
Port: 42,
}, edKey); err == nil {
t.Fatalf("no error for unknown address")
} else if ke, ok := err.(*KeyError); !ok {
t.Fatalf("got type %T, want *KeyError", err)
} else if len(ke.Want) > 0 {
t.Fatalf("got Want %v, want []", ke.Want)
}
}
func TestNewKeyType(t *testing.T) {
str := fmt.Sprintf("%s %s", testAddr, edKeyStr)
db := testDB(t, str)
if err := db.check("", testAddr, ecKey); err == nil {
t.Fatalf("no error for unknown address")
} else if ke, ok := err.(*KeyError); !ok {
t.Fatalf("got type %T, want *KeyError", err)
} else if len(ke.Want) == 0 {
t.Fatalf("got empty KeyError.Want")
}
}
func TestSameKeyType(t *testing.T) {
str := fmt.Sprintf("%s %s", testAddr, edKeyStr)
db := testDB(t, str)
if err := db.check("", testAddr, alternateEdKey); err == nil {
t.Fatalf("no error for unknown address")
} else if ke, ok := err.(*KeyError); !ok {
t.Fatalf("got type %T, want *KeyError", err)
} else if len(ke.Want) == 0 {
t.Fatalf("got empty KeyError.Want")
} else if got, want := ke.Want[0].Key.Marshal(), edKey.Marshal(); !bytes.Equal(got, want) {
t.Fatalf("got key %q, want %q", got, want)
}
}
func TestIPAddress(t *testing.T) {
str := fmt.Sprintf("%s %s", testAddr, edKeyStr)
db := testDB(t, str)
if err := db.check("", testAddr, edKey); err != nil {
t.Errorf("got error %q, want none", err)
}
}
func TestIPv6Address(t *testing.T) {
str := fmt.Sprintf("%s %s", testAddr6, edKeyStr)
db := testDB(t, str)
if err := db.check("", testAddr6, edKey); err != nil {
t.Errorf("got error %q, want none", err)
}
}
func TestBasic(t *testing.T) {
str := fmt.Sprintf("#comment\n\nserver.org,%s %s\notherhost %s", testAddr, edKeyStr, ecKeyStr)
db := testDB(t, str)
if err := db.check("server.org:22", testAddr, edKey); err != nil {
t.Errorf("got error %q, want none", err)
}
want := KnownKey{
Key: edKey,
Filename: "testdb",
Line: 3,
}
if err := db.check("server.org:22", testAddr, ecKey); err == nil {
t.Errorf("succeeded, want KeyError")
} else if ke, ok := err.(*KeyError); !ok {
t.Errorf("got %T, want *KeyError", err)
} else if len(ke.Want) != 1 {
t.Errorf("got %v, want 1 entry", ke)
} else if !reflect.DeepEqual(ke.Want[0], want) {
t.Errorf("got %v, want %v", ke.Want[0], want)
}
}
func TestNegate(t *testing.T) {
str := fmt.Sprintf("%s,!server.org %s", testAddr, edKeyStr)
db := testDB(t, str)
if err := db.check("server.org:22", testAddr, ecKey); err == nil {
t.Errorf("succeeded")
} else if ke, ok := err.(*KeyError); !ok {
t.Errorf("got error type %T, want *KeyError", err)
} else if len(ke.Want) != 0 {
t.Errorf("got expected keys %d (first of type %s), want []", len(ke.Want), ke.Want[0].Key.Type())
}
}
func TestWildcard(t *testing.T) {
str := fmt.Sprintf("server*.domain %s", edKeyStr)
db := testDB(t, str)
want := &KeyError{
Want: []KnownKey{{
Filename: "testdb",
Line: 1,
Key: edKey,
}},
}
got := db.check("server.domain:22", &net.TCPAddr{}, ecKey)
if !reflect.DeepEqual(got, want) {
t.Errorf("got %s, want %s", got, want)
}
}
func TestLine(t *testing.T) {
for in, want := range map[string]string{
"server.org": "server.org " + edKeyStr,
"server.org:22": "server.org " + edKeyStr,
"server.org:23": "[server.org]:23 " + edKeyStr,
"[c629:1ec4:102:304:102:304:102:304]:22": "[c629:1ec4:102:304:102:304:102:304] " + edKeyStr,
"[c629:1ec4:102:304:102:304:102:304]:23": "[c629:1ec4:102:304:102:304:102:304]:23 " + edKeyStr,
} {
if got := Line([]string{in}, edKey); got != want {
t.Errorf("Line(%q) = %q, want %q", in, got, want)
}
}
}
func TestWildcardMatch(t *testing.T) {
for _, c := range []struct {
pat, str string
want bool
}{
{"a?b", "abb", true},
{"ab", "abc", false},
{"abc", "ab", false},
{"a*b", "axxxb", true},
{"a*b", "axbxb", true},
{"a*b", "axbxbc", false},
{"a*?", "axbxc", true},
{"a*b*", "axxbxxxxxx", true},
{"a*b*c", "axxbxxxxxxc", true},
{"a*b*?", "axxbxxxxxxc", true},
{"a*b*z", "axxbxxbxxxz", true},
{"a*b*z", "axxbxxzxxxz", true},
{"a*b*z", "axxbxxzxxx", false},
} {
got := wildcardMatch([]byte(c.pat), []byte(c.str))
if got != c.want {
t.Errorf("wildcardMatch(%q, %q) = %v, want %v", c.pat, c.str, got, c.want)
}
}
}
// TODO(hanwen): test coverage for certificates.
const testHostname = "hostname"
// generated with keygen -H -f
const encodedTestHostnameHash = "|1|IHXZvQMvTcZTUU29+2vXFgx8Frs=|UGccIWfRVDwilMBnA3WJoRAC75Y="
func TestHostHash(t *testing.T) {
testHostHash(t, testHostname, encodedTestHostnameHash)
}
func TestHashList(t *testing.T) {
encoded := HashHostname(testHostname)
testHostHash(t, testHostname, encoded)
}
func testHostHash(t *testing.T, hostname, encoded string) {
typ, salt, hash, err := decodeHash(encoded)
if err != nil {
t.Fatalf("decodeHash: %v", err)
}
if got := encodeHash(typ, salt, hash); got != encoded {
t.Errorf("got encoding %s want %s", got, encoded)
}
if typ != sha1HashType {
t.Fatalf("got hash type %q, want %q", typ, sha1HashType)
}
got := hashHost(hostname, salt)
if !bytes.Equal(got, hash) {
t.Errorf("got hash %x want %x", got, hash)
}
}
func TestNormalize(t *testing.T) {
for in, want := range map[string]string{
"127.0.0.1:22": "127.0.0.1",
"[127.0.0.1]:22": "127.0.0.1",
"[127.0.0.1]:23": "[127.0.0.1]:23",
"127.0.0.1:23": "[127.0.0.1]:23",
"[a.b.c]:22": "a.b.c",
"[abcd:abcd:abcd:abcd]": "[abcd:abcd:abcd:abcd]",
"[abcd:abcd:abcd:abcd]:22": "[abcd:abcd:abcd:abcd]",
"[abcd:abcd:abcd:abcd]:23": "[abcd:abcd:abcd:abcd]:23",
} {
got := Normalize(in)
if got != want {
t.Errorf("Normalize(%q) = %q, want %q", in, got, want)
}
}
}
func TestHashedHostkeyCheck(t *testing.T) {
str := fmt.Sprintf("%s %s", HashHostname(testHostname), edKeyStr)
db := testDB(t, str)
if err := db.check(testHostname+":22", testAddr, edKey); err != nil {
t.Errorf("check(%s): %v", testHostname, err)
}
want := &KeyError{
Want: []KnownKey{{
Filename: "testdb",
Line: 1,
Key: edKey,
}},
}
if got := db.check(testHostname+":22", testAddr, alternateEdKey); !reflect.DeepEqual(got, want) {
t.Errorf("got error %v, want %v", got, want)
}
}

10
ssh/mac.go
View file

@ -15,6 +15,7 @@ import (
type macMode struct {
keySize int
etm bool
new func(key []byte) hash.Hash
}
@ -45,13 +46,16 @@ func (t truncatingMAC) Size() int {
func (t truncatingMAC) BlockSize() int { return t.hmac.BlockSize() }
var macModes = map[string]*macMode{
"hmac-sha2-256": {32, func(key []byte) hash.Hash {
"hmac-sha2-256-etm@openssh.com": {32, true, func(key []byte) hash.Hash {
return hmac.New(sha256.New, key)
}},
"hmac-sha1": {20, func(key []byte) hash.Hash {
"hmac-sha2-256": {32, false, func(key []byte) hash.Hash {
return hmac.New(sha256.New, key)
}},
"hmac-sha1": {20, false, func(key []byte) hash.Hash {
return hmac.New(sha1.New, key)
}},
"hmac-sha1-96": {20, func(key []byte) hash.Hash {
"hmac-sha1-96": {20, false, func(key []byte) hash.Hash {
return truncatingMAC{12, hmac.New(sha1.New, key)}
}},
}

4
ssh/mux.go
View file

@ -116,9 +116,9 @@ func (m *mux) Wait() error {
func newMux(p packetConn) *mux {
m := &mux{
conn: p,
incomingChannels: make(chan NewChannel, 16),
incomingChannels: make(chan NewChannel, chanSize),
globalResponses: make(chan interface{}, 1),
incomingRequests: make(chan *Request, 16),
incomingRequests: make(chan *Request, chanSize),
errCond: newCond(),
}
if debugMux {

3
ssh/mux_test.go
View file

@ -499,4 +499,7 @@ func TestDebug(t *testing.T) {
if debugHandshake {
t.Error("handshake debug switched on")
}
if debugTransport {
t.Error("transport debug switched on")
}
}

118
ssh/server.go
View file

@ -10,26 +10,38 @@ import (
"fmt"
"io"
"net"
"strings"
)
// The Permissions type holds fine-grained permissions that are
// specific to a user or a specific authentication method for a
// user. Permissions, except for "source-address", must be enforced in
// the server application layer, after successful authentication. The
// Permissions are passed on in ServerConn so a server implementation
// can honor them.
// specific to a user or a specific authentication method for a user.
// The Permissions value for a successful authentication attempt is
// available in ServerConn, so it can be used to pass information from
// the user-authentication phase to the application layer.
type Permissions struct {
// Critical options restrict default permissions. Common
// restrictions are "source-address" and "force-command". If
// the server cannot enforce the restriction, or does not
// recognize it, the user should not authenticate.
// CriticalOptions indicate restrictions to the default
// permissions, and are typically used in conjunction with
// user certificates. The standard for SSH certificates
// defines "force-command" (only allow the given command to
// execute) and "source-address" (only allow connections from
// the given address). The SSH package currently only enforces
// the "source-address" critical option. It is up to server
// implementations to enforce other critical options, such as
// "force-command", by checking them after the SSH handshake
// is successful. In general, SSH servers should reject
// connections that specify critical options that are unknown
// or not supported.
CriticalOptions map[string]string
// Extensions are extra functionality that the server may
// offer on authenticated connections. Common extensions are
// "permit-agent-forwarding", "permit-X11-forwarding". Lack of
// support for an extension does not preclude authenticating a
// user.
// offer on authenticated connections. Lack of support for an
// extension does not preclude authenticating a user. Common
// extensions are "permit-agent-forwarding",
// "permit-X11-forwarding". The Go SSH library currently does
// not act on any extension, and it is up to server
// implementations to honor them. Extensions can be used to
// pass data from the authentication callbacks to the server
// application layer.
Extensions map[string]string
}
@ -44,13 +56,24 @@ type ServerConfig struct {
// authenticating.
NoClientAuth bool
// MaxAuthTries specifies the maximum number of authentication attempts
// permitted per connection. If set to a negative number, the number of
// attempts are unlimited. If set to zero, the number of attempts are limited
// to 6.
MaxAuthTries int
// PasswordCallback, if non-nil, is called when a user
// attempts to authenticate using a password.
PasswordCallback func(conn ConnMetadata, password []byte) (*Permissions, error)
// PublicKeyCallback, if non-nil, is called when a client attempts public
// key authentication. It must return true if the given public key is
// valid for the given user. For example, see CertChecker.Authenticate.
// PublicKeyCallback, if non-nil, is called when a client
// offers a public key for authentication. It must return true
// if the given public key can be used to authenticate the
// given user. For example, see CertChecker.Authenticate. A
// call to this function does not guarantee that the key
// offered is in fact used to authenticate. To record any data
// depending on the public key, store it inside a
// Permissions.Extensions entry.
PublicKeyCallback func(conn ConnMetadata, key PublicKey) (*Permissions, error)
// KeyboardInteractiveCallback, if non-nil, is called when
@ -142,6 +165,10 @@ type ServerConn struct {
func NewServerConn(c net.Conn, config *ServerConfig) (*ServerConn, <-chan NewChannel, <-chan *Request, error) {
fullConf := *config
fullConf.SetDefaults()
if fullConf.MaxAuthTries == 0 {
fullConf.MaxAuthTries = 6
}
s := &connection{
sshConn: sshConn{conn: c},
}
@ -188,7 +215,7 @@ func (s *connection) serverHandshake(config *ServerConfig) (*Permissions, error)
tr := newTransport(s.sshConn.conn, config.Rand, false /* not client */)
s.transport = newServerTransport(tr, s.clientVersion, s.serverVersion, config)
if err := s.transport.requestInitialKeyChange(); err != nil {
if err := s.transport.waitSession(); err != nil {
return nil, err
}
@ -231,7 +258,7 @@ func isAcceptableAlgo(algo string) bool {
return false
}
func checkSourceAddress(addr net.Addr, sourceAddr string) error {
func checkSourceAddress(addr net.Addr, sourceAddrs string) error {
if addr == nil {
return errors.New("ssh: no address known for client, but source-address match required")
}
@ -241,18 +268,20 @@ func checkSourceAddress(addr net.Addr, sourceAddr string) error {
return fmt.Errorf("ssh: remote address %v is not an TCP address when checking source-address match", addr)
}
if allowedIP := net.ParseIP(sourceAddr); allowedIP != nil {
if bytes.Equal(allowedIP, tcpAddr.IP) {
return nil
}
} else {
_, ipNet, err := net.ParseCIDR(sourceAddr)
if err != nil {
return fmt.Errorf("ssh: error parsing source-address restriction %q: %v", sourceAddr, err)
}
for _, sourceAddr := range strings.Split(sourceAddrs, ",") {
if allowedIP := net.ParseIP(sourceAddr); allowedIP != nil {
if allowedIP.Equal(tcpAddr.IP) {
return nil
}
} else {
_, ipNet, err := net.ParseCIDR(sourceAddr)
if err != nil {
return fmt.Errorf("ssh: error parsing source-address restriction %q: %v", sourceAddr, err)
}
if ipNet.Contains(tcpAddr.IP) {
return nil
if ipNet.Contains(tcpAddr.IP) {
return nil
}
}
}
@ -260,12 +289,27 @@ func checkSourceAddress(addr net.Addr, sourceAddr string) error {
}
func (s *connection) serverAuthenticate(config *ServerConfig) (*Permissions, error) {
var err error
sessionID := s.transport.getSessionID()
var cache pubKeyCache
var perms *Permissions
authFailures := 0
userAuthLoop:
for {
if authFailures >= config.MaxAuthTries && config.MaxAuthTries > 0 {
discMsg := &disconnectMsg{
Reason: 2,
Message: "too many authentication failures",
}
if err := s.transport.writePacket(Marshal(discMsg)); err != nil {
return nil, err
}
return nil, discMsg
}
var userAuthReq userAuthRequestMsg
if packet, err := s.transport.readPacket(); err != nil {
return nil, err
@ -286,6 +330,11 @@ userAuthLoop:
if config.NoClientAuth {
authErr = nil
}
// allow initial attempt of 'none' without penalty
if authFailures == 0 {
authFailures--
}
case "password":
if config.PasswordCallback == nil {
authErr = errors.New("ssh: password auth not configured")
@ -357,6 +406,7 @@ userAuthLoop:
if isQuery {
// The client can query if the given public key
// would be okay.
if len(payload) > 0 {
return nil, parseError(msgUserAuthRequest)
}
@ -385,7 +435,7 @@ userAuthLoop:
if !isAcceptableAlgo(sig.Format) {
break
}
signedData := buildDataSignedForAuth(s.transport.getSessionID(), userAuthReq, algoBytes, pubKeyData)
signedData := buildDataSignedForAuth(sessionID, userAuthReq, algoBytes, pubKeyData)
if err := pubKey.Verify(signedData, sig); err != nil {
return nil, err
@ -406,6 +456,8 @@ userAuthLoop:
break userAuthLoop
}
authFailures++
var failureMsg userAuthFailureMsg
if config.PasswordCallback != nil {
failureMsg.Methods = append(failureMsg.Methods, "password")
@ -421,12 +473,12 @@ userAuthLoop:
return nil, errors.New("ssh: no authentication methods configured but NoClientAuth is also false")
}
if err = s.transport.writePacket(Marshal(&failureMsg)); err != nil {
if err := s.transport.writePacket(Marshal(&failureMsg)); err != nil {
return nil, err
}
}
if err = s.transport.writePacket([]byte{msgUserAuthSuccess}); err != nil {
if err := s.transport.writePacket([]byte{msgUserAuthSuccess}); err != nil {
return nil, err
}
return perms, nil

10
ssh/session_test.go
View file

@ -59,7 +59,8 @@ func dial(handler serverType, t *testing.T) *Client {
}()
config := &ClientConfig{
User: "testuser",
User: "testuser",
HostKeyCallback: InsecureIgnoreHostKey(),
}
conn, chans, reqs, err := NewClientConn(c2, "", config)
@ -641,7 +642,8 @@ func TestSessionID(t *testing.T) {
}
serverConf.AddHostKey(testSigners["ecdsa"])
clientConf := &ClientConfig{
User: "user",
HostKeyCallback: InsecureIgnoreHostKey(),
User: "user",
}
go func() {
@ -747,7 +749,9 @@ func TestHostKeyAlgorithms(t *testing.T) {
// By default, we get the preferred algorithm, which is ECDSA 256.
clientConf := &ClientConfig{}
clientConf := &ClientConfig{
HostKeyCallback: InsecureIgnoreHostKey(),
}
connect(clientConf, KeyAlgoECDSA256)
// Client asks for RSA explicitly.

115
ssh/streamlocal.go Normal file
View file

@ -0,0 +1,115 @@
package ssh
import (
"errors"
"io"
"net"
)
// streamLocalChannelOpenDirectMsg is a struct used for SSH_MSG_CHANNEL_OPEN message
// with "direct-streamlocal@openssh.com" string.
//
// See openssh-portable/PROTOCOL, section 2.4. connection: Unix domain socket forwarding
// https://github.com/openssh/openssh-portable/blob/master/PROTOCOL#L235
type streamLocalChannelOpenDirectMsg struct {
socketPath string
reserved0 string
reserved1 uint32
}
// forwardedStreamLocalPayload is a struct used for SSH_MSG_CHANNEL_OPEN message
// with "forwarded-streamlocal@openssh.com" string.
type forwardedStreamLocalPayload struct {
SocketPath string
Reserved0 string
}
// streamLocalChannelForwardMsg is a struct used for SSH2_MSG_GLOBAL_REQUEST message
// with "streamlocal-forward@openssh.com"/"cancel-streamlocal-forward@openssh.com" string.
type streamLocalChannelForwardMsg struct {
socketPath string
}
// ListenUnix is similar to ListenTCP but uses a Unix domain socket.
func (c *Client) ListenUnix(socketPath string) (net.Listener, error) {
m := streamLocalChannelForwardMsg{
socketPath,
}
// send message
ok, _, err := c.SendRequest("streamlocal-forward@openssh.com", true, Marshal(&m))
if err != nil {
return nil, err
}
if !ok {
return nil, errors.New("ssh: streamlocal-forward@openssh.com request denied by peer")
}
ch := c.forwards.add(&net.UnixAddr{Name: socketPath, Net: "unix"})
return &unixListener{socketPath, c, ch}, nil
}
func (c *Client) dialStreamLocal(socketPath string) (Channel, error) {
msg := streamLocalChannelOpenDirectMsg{
socketPath: socketPath,
}
ch, in, err := c.OpenChannel("direct-streamlocal@openssh.com", Marshal(&msg))
if err != nil {
return nil, err
}
go DiscardRequests(in)
return ch, err
}
type unixListener struct {
socketPath string
conn *Client
in <-chan forward
}
// Accept waits for and returns the next connection to the listener.
func (l *unixListener) Accept() (net.Conn, error) {
s, ok := <-l.in
if !ok {
return nil, io.EOF
}
ch, incoming, err := s.newCh.Accept()
if err != nil {
return nil, err
}
go DiscardRequests(incoming)
return &chanConn{
Channel: ch,
laddr: &net.UnixAddr{
Name: l.socketPath,
Net: "unix",
},
raddr: &net.UnixAddr{
Name: "@",
Net: "unix",
},
}, nil
}
// Close closes the listener.
func (l *unixListener) Close() error {
// this also closes the listener.
l.conn.forwards.remove(&net.UnixAddr{Name: l.socketPath, Net: "unix"})
m := streamLocalChannelForwardMsg{
l.socketPath,
}
ok, _, err := l.conn.SendRequest("cancel-streamlocal-forward@openssh.com", true, Marshal(&m))
if err == nil && !ok {
err = errors.New("ssh: cancel-streamlocal-forward@openssh.com failed")
}
return err
}
// Addr returns the listener's network address.
func (l *unixListener) Addr() net.Addr {
return &net.UnixAddr{
Name: l.socketPath,
Net: "unix",
}
}

196
ssh/tcpip.go
View file

@ -20,12 +20,20 @@ import (
// addr. Incoming connections will be available by calling Accept on
// the returned net.Listener. The listener must be serviced, or the
// SSH connection may hang.
// N must be "tcp", "tcp4", "tcp6", or "unix".
func (c *Client) Listen(n, addr string) (net.Listener, error) {
laddr, err := net.ResolveTCPAddr(n, addr)
if err != nil {
return nil, err
switch n {
case "tcp", "tcp4", "tcp6":
laddr, err := net.ResolveTCPAddr(n, addr)
if err != nil {
return nil, err
}
return c.ListenTCP(laddr)
case "unix":
return c.ListenUnix(addr)
default:
return nil, fmt.Errorf("ssh: unsupported protocol: %s", n)
}
return c.ListenTCP(laddr)
}
// Automatic port allocation is broken with OpenSSH before 6.0. See
@ -116,7 +124,7 @@ func (c *Client) ListenTCP(laddr *net.TCPAddr) (net.Listener, error) {
}
// Register this forward, using the port number we obtained.
ch := c.forwards.add(*laddr)
ch := c.forwards.add(laddr)
return &tcpListener{laddr, c, ch}, nil
}
@ -131,7 +139,7 @@ type forwardList struct {
// forwardEntry represents an established mapping of a laddr on a
// remote ssh server to a channel connected to a tcpListener.
type forwardEntry struct {
laddr net.TCPAddr
laddr net.Addr
c chan forward
}
@ -139,16 +147,16 @@ type forwardEntry struct {
// arguments to add/remove/lookup should be address as specified in
// the original forward-request.
type forward struct {
newCh NewChannel // the ssh client channel underlying this forward
raddr *net.TCPAddr // the raddr of the incoming connection
newCh NewChannel // the ssh client channel underlying this forward
raddr net.Addr // the raddr of the incoming connection
}
func (l *forwardList) add(addr net.TCPAddr) chan forward {
func (l *forwardList) add(addr net.Addr) chan forward {
l.Lock()
defer l.Unlock()
f := forwardEntry{
addr,
make(chan forward, 1),
laddr: addr,
c: make(chan forward, 1),
}
l.entries = append(l.entries, f)
return f.c
@ -176,44 +184,69 @@ func parseTCPAddr(addr string, port uint32) (*net.TCPAddr, error) {
func (l *forwardList) handleChannels(in <-chan NewChannel) {
for ch := range in {
var payload forwardedTCPPayload
if err := Unmarshal(ch.ExtraData(), &payload); err != nil {
ch.Reject(ConnectionFailed, "could not parse forwarded-tcpip payload: "+err.Error())
continue
}
var (
laddr net.Addr
raddr net.Addr
err error
)
switch channelType := ch.ChannelType(); channelType {
case "forwarded-tcpip":
var payload forwardedTCPPayload
if err = Unmarshal(ch.ExtraData(), &payload); err != nil {
ch.Reject(ConnectionFailed, "could not parse forwarded-tcpip payload: "+err.Error())
continue
}
// RFC 4254 section 7.2 specifies that incoming
// addresses should list the address, in string
// format. It is implied that this should be an IP
// address, as it would be impossible to connect to it
// otherwise.
laddr, err := parseTCPAddr(payload.Addr, payload.Port)
if err != nil {
ch.Reject(ConnectionFailed, err.Error())
continue
}
raddr, err := parseTCPAddr(payload.OriginAddr, payload.OriginPort)
if err != nil {
ch.Reject(ConnectionFailed, err.Error())
continue
}
// RFC 4254 section 7.2 specifies that incoming
// addresses should list the address, in string
// format. It is implied that this should be an IP
// address, as it would be impossible to connect to it
// otherwise.
laddr, err = parseTCPAddr(payload.Addr, payload.Port)
if err != nil {
ch.Reject(ConnectionFailed, err.Error())
continue
}
raddr, err = parseTCPAddr(payload.OriginAddr, payload.OriginPort)
if err != nil {
ch.Reject(ConnectionFailed, err.Error())
continue
}
if ok := l.forward(*laddr, *raddr, ch); !ok {
case "forwarded-streamlocal@openssh.com":
var payload forwardedStreamLocalPayload
if err = Unmarshal(ch.ExtraData(), &payload); err != nil {
ch.Reject(ConnectionFailed, "could not parse forwarded-streamlocal@openssh.com payload: "+err.Error())
continue
}
laddr = &net.UnixAddr{
Name: payload.SocketPath,
Net: "unix",
}
raddr = &net.UnixAddr{
Name: "@",
Net: "unix",
}
default:
panic(fmt.Errorf("ssh: unknown channel type %s", channelType))
}
if ok := l.forward(laddr, raddr, ch); !ok {
// Section 7.2, implementations MUST reject spurious incoming
// connections.
ch.Reject(Prohibited, "no forward for address")
continue
}
}
}
// remove removes the forward entry, and the channel feeding its
// listener.
func (l *forwardList) remove(addr net.TCPAddr) {
func (l *forwardList) remove(addr net.Addr) {
l.Lock()
defer l.Unlock()
for i, f := range l.entries {
if addr.IP.Equal(f.laddr.IP) && addr.Port == f.laddr.Port {
if addr.Network() == f.laddr.Network() && addr.String() == f.laddr.String() {
l.entries = append(l.entries[:i], l.entries[i+1:]...)
close(f.c)
return
@ -231,12 +264,12 @@ func (l *forwardList) closeAll() {
l.entries = nil
}
func (l *forwardList) forward(laddr, raddr net.TCPAddr, ch NewChannel) bool {
func (l *forwardList) forward(laddr, raddr net.Addr, ch NewChannel) bool {
l.Lock()
defer l.Unlock()
for _, f := range l.entries {
if laddr.IP.Equal(f.laddr.IP) && laddr.Port == f.laddr.Port {
f.c <- forward{ch, &raddr}
if laddr.Network() == f.laddr.Network() && laddr.String() == f.laddr.String() {
f.c <- forward{newCh: ch, raddr: raddr}
return true
}
}
@ -262,7 +295,7 @@ func (l *tcpListener) Accept() (net.Conn, error) {
}
go DiscardRequests(incoming)
return &tcpChanConn{
return &chanConn{
Channel: ch,
laddr: l.laddr,
raddr: s.raddr,
@ -277,7 +310,7 @@ func (l *tcpListener) Close() error {
}
// this also closes the listener.
l.conn.forwards.remove(*l.laddr)
l.conn.forwards.remove(l.laddr)
ok, _, err := l.conn.SendRequest("cancel-tcpip-forward", true, Marshal(&m))
if err == nil && !ok {
err = errors.New("ssh: cancel-tcpip-forward failed")
@ -293,29 +326,52 @@ func (l *tcpListener) Addr() net.Addr {
// Dial initiates a connection to the addr from the remote host.
// The resulting connection has a zero LocalAddr() and RemoteAddr().
func (c *Client) Dial(n, addr string) (net.Conn, error) {
// Parse the address into host and numeric port.
host, portString, err := net.SplitHostPort(addr)
if err != nil {
return nil, err
var ch Channel
switch n {
case "tcp", "tcp4", "tcp6":
// Parse the address into host and numeric port.
host, portString, err := net.SplitHostPort(addr)
if err != nil {
return nil, err
}
port, err := strconv.ParseUint(portString, 10, 16)
if err != nil {
return nil, err
}
ch, err = c.dial(net.IPv4zero.String(), 0, host, int(port))
if err != nil {
return nil, err
}
// Use a zero address for local and remote address.
zeroAddr := &net.TCPAddr{
IP: net.IPv4zero,
Port: 0,
}
return &chanConn{
Channel: ch,
laddr: zeroAddr,
raddr: zeroAddr,
}, nil
case "unix":
var err error
ch, err = c.dialStreamLocal(addr)
if err != nil {
return nil, err
}
return &chanConn{
Channel: ch,
laddr: &net.UnixAddr{
Name: "@",
Net: "unix",
},
raddr: &net.UnixAddr{
Name: addr,
Net: "unix",
},
}, nil
default:
return nil, fmt.Errorf("ssh: unsupported protocol: %s", n)
}
port, err := strconv.ParseUint(portString, 10, 16)
if err != nil {
return nil, err
}
// Use a zero address for local and remote address.
zeroAddr := &net.TCPAddr{
IP: net.IPv4zero,
Port: 0,
}
ch, err := c.dial(net.IPv4zero.String(), 0, host, int(port))
if err != nil {
return nil, err
}
return &tcpChanConn{
Channel: ch,
laddr: zeroAddr,
raddr: zeroAddr,
}, nil
}
// DialTCP connects to the remote address raddr on the network net,
@ -332,7 +388,7 @@ func (c *Client) DialTCP(n string, laddr, raddr *net.TCPAddr) (net.Conn, error)
if err != nil {
return nil, err
}
return &tcpChanConn{
return &chanConn{
Channel: ch,
laddr: laddr,
raddr: raddr,
@ -366,26 +422,26 @@ type tcpChan struct {
Channel // the backing channel
}
// tcpChanConn fulfills the net.Conn interface without
// chanConn fulfills the net.Conn interface without
// the tcpChan having to hold laddr or raddr directly.
type tcpChanConn struct {
type chanConn struct {
Channel
laddr, raddr net.Addr
}
// LocalAddr returns the local network address.
func (t *tcpChanConn) LocalAddr() net.Addr {
func (t *chanConn) LocalAddr() net.Addr {
return t.laddr
}
// RemoteAddr returns the remote network address.
func (t *tcpChanConn) RemoteAddr() net.Addr {
func (t *chanConn) RemoteAddr() net.Addr {
return t.raddr
}
// SetDeadline sets the read and write deadlines associated
// with the connection.
func (t *tcpChanConn) SetDeadline(deadline time.Time) error {
func (t *chanConn) SetDeadline(deadline time.Time) error {
if err := t.SetReadDeadline(deadline); err != nil {
return err
}
@ -396,12 +452,14 @@ func (t *tcpChanConn) SetDeadline(deadline time.Time) error {
// A zero value for t means Read will not time out.
// After the deadline, the error from Read will implement net.Error
// with Timeout() == true.
func (t *tcpChanConn) SetReadDeadline(deadline time.Time) error {
func (t *chanConn) SetReadDeadline(deadline time.Time) error {
// for compatibility with previous version,
// the error message contains "tcpChan"
return errors.New("ssh: tcpChan: deadline not supported")
}
// SetWriteDeadline exists to satisfy the net.Conn interface
// but is not implemented by this type. It always returns an error.
func (t *tcpChanConn) SetWriteDeadline(deadline time.Time) error {
func (t *chanConn) SetWriteDeadline(deadline time.Time) error {
return errors.New("ssh: tcpChan: deadline not supported")
}

73
ssh/terminal/terminal.go
View file

@ -132,8 +132,11 @@ const (
keyPasteEnd
)
var pasteStart = []byte{keyEscape, '[', '2', '0', '0', '~'}
var pasteEnd = []byte{keyEscape, '[', '2', '0', '1', '~'}
var (
crlf = []byte{'\r', '\n'}
pasteStart = []byte{keyEscape, '[', '2', '0', '0', '~'}
pasteEnd = []byte{keyEscape, '[', '2', '0', '1', '~'}
)
// bytesToKey tries to parse a key sequence from b. If successful, it returns
// the key and the remainder of the input. Otherwise it returns utf8.RuneError.
@ -333,7 +336,7 @@ func (t *Terminal) advanceCursor(places int) {
// So, if we are stopping at the end of a line, we
// need to write a newline so that our cursor can be
// advanced to the next line.
t.outBuf = append(t.outBuf, '\n')
t.outBuf = append(t.outBuf, '\r', '\n')
}
}
@ -593,6 +596,35 @@ func (t *Terminal) writeLine(line []rune) {
}
}
// writeWithCRLF writes buf to w but replaces all occurrences of \n with \r\n.
func writeWithCRLF(w io.Writer, buf []byte) (n int, err error) {
for len(buf) > 0 {
i := bytes.IndexByte(buf, '\n')
todo := len(buf)
if i >= 0 {
todo = i
}
var nn int
nn, err = w.Write(buf[:todo])
n += nn
if err != nil {
return n, err
}
buf = buf[todo:]
if i >= 0 {
if _, err = w.Write(crlf); err != nil {
return n, err
}
n += 1
buf = buf[1:]
}
}
return n, nil
}
func (t *Terminal) Write(buf []byte) (n int, err error) {
t.lock.Lock()
defer t.lock.Unlock()
@ -600,7 +632,7 @@ func (t *Terminal) Write(buf []byte) (n int, err error) {
if t.cursorX == 0 && t.cursorY == 0 {
// This is the easy case: there's nothing on the screen that we
// have to move out of the way.
return t.c.Write(buf)
return writeWithCRLF(t.c, buf)
}
// We have a prompt and possibly user input on the screen. We
@ -620,7 +652,7 @@ func (t *Terminal) Write(buf []byte) (n int, err error) {
}
t.outBuf = t.outBuf[:0]
if n, err = t.c.Write(buf); err != nil {
if n, err = writeWithCRLF(t.c, buf); err != nil {
return
}
@ -740,8 +772,6 @@ func (t *Terminal) readLine() (line string, err error) {
t.remainder = t.inBuf[:n+len(t.remainder)]
}
panic("unreachable") // for Go 1.0.
}
// SetPrompt sets the prompt to be used when reading subsequent lines.
@ -890,3 +920,32 @@ func (s *stRingBuffer) NthPreviousEntry(n int) (value string, ok bool) {
}
return s.entries[index], true
}
// readPasswordLine reads from reader until it finds \n or io.EOF.
// The slice returned does not include the \n.
// readPasswordLine also ignores any \r it finds.
func readPasswordLine(reader io.Reader) ([]byte, error) {
var buf [1]byte
var ret []byte
for {
n, err := reader.Read(buf[:])
if n > 0 {
switch buf[0] {
case '\n':
return ret, nil
case '\r':
// remove \r from passwords on Windows
default:
ret = append(ret, buf[0])
}
continue
}
if err != nil {
if err == io.EOF && len(ret) > 0 {
return ret, nil
}
return ret, err
}
}
}

59
ssh/terminal/terminal_test.go
View file

@ -5,6 +5,7 @@
package terminal
import (
"bytes"
"io"
"os"
"testing"
@ -269,6 +270,50 @@ func TestTerminalSetSize(t *testing.T) {
}
}
func TestReadPasswordLineEnd(t *testing.T) {
var tests = []struct {
input string
want string
}{
{"\n", ""},
{"\r\n", ""},
{"test\r\n", "test"},
{"testtesttesttes\n", "testtesttesttes"},
{"testtesttesttes\r\n", "testtesttesttes"},
{"testtesttesttesttest\n", "testtesttesttesttest"},
{"testtesttesttesttest\r\n", "testtesttesttesttest"},
}
for _, test := range tests {
buf := new(bytes.Buffer)
if _, err := buf.WriteString(test.input); err != nil {
t.Fatal(err)
}
have, err := readPasswordLine(buf)
if err != nil {
t.Errorf("readPasswordLine(%q) failed: %v", test.input, err)
continue
}
if string(have) != test.want {
t.Errorf("readPasswordLine(%q) returns %q, but %q is expected", test.input, string(have), test.want)
continue
}
if _, err = buf.WriteString(test.input); err != nil {
t.Fatal(err)
}
have, err = readPasswordLine(buf)
if err != nil {
t.Errorf("readPasswordLine(%q) failed: %v", test.input, err)
continue
}
if string(have) != test.want {
t.Errorf("readPasswordLine(%q) returns %q, but %q is expected", test.input, string(have), test.want)
continue
}
}
}
func TestMakeRawState(t *testing.T) {
fd := int(os.Stdout.Fd())
if !IsTerminal(fd) {
@ -289,3 +334,17 @@ func TestMakeRawState(t *testing.T) {
t.Errorf("states do not match; was %v, expected %v", raw, st)
}
}
func TestOutputNewlines(t *testing.T) {
// \n should be changed to \r\n in terminal output.
buf := new(bytes.Buffer)
term := NewTerminal(buf, ">")
term.Write([]byte("1\n2\n"))
output := string(buf.Bytes())
const expected = "1\r\n2\r\n"
if output != expected {
t.Errorf("incorrect output: was %q, expected %q", output, expected)
}
}

38
ssh/terminal/util.go
View file

@ -17,7 +17,6 @@
package terminal
import (
"io"
"syscall"
"unsafe"
)
@ -72,8 +71,10 @@ func GetState(fd int) (*State, error) {
// Restore restores the terminal connected to the given file descriptor to a
// previous state.
func Restore(fd int, state *State) error {
_, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&state.termios)), 0, 0, 0)
return err
if _, _, err := syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&state.termios)), 0, 0, 0); err != 0 {
return err
}
return nil
}
// GetSize returns the dimensions of the given terminal.
@ -86,6 +87,13 @@ func GetSize(fd int) (width, height int, err error) {
return int(dimensions[1]), int(dimensions[0]), nil
}
// passwordReader is an io.Reader that reads from a specific file descriptor.
type passwordReader int
func (r passwordReader) Read(buf []byte) (int, error) {
return syscall.Read(int(r), buf)
}
// ReadPassword reads a line of input from a terminal without local echo. This
// is commonly used for inputting passwords and other sensitive data. The slice
// returned does not include the \n.
@ -107,27 +115,5 @@ func ReadPassword(fd int) ([]byte, error) {
syscall.Syscall6(syscall.SYS_IOCTL, uintptr(fd), ioctlWriteTermios, uintptr(unsafe.Pointer(&oldState)), 0, 0, 0)
}()
var buf [16]byte
var ret []byte
for {
n, err := syscall.Read(fd, buf[:])
if err != nil {
return nil, err
}
if n == 0 {
if len(ret) == 0 {
return nil, io.EOF
}
break
}
if buf[n-1] == '\n' {
n--
}
ret = append(ret, buf[:n]...)
if n < len(buf) {
break
}
}
return ret, nil
return readPasswordLine(passwordReader(fd))
}

128
ssh/terminal/util_solaris.go Normal file
View file

@ -0,0 +1,128 @@
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build solaris
package terminal // import "golang.org/x/crypto/ssh/terminal"
import (
"golang.org/x/sys/unix"
"io"
"syscall"
)
// State contains the state of a terminal.
type State struct {
state *unix.Termios
}
// IsTerminal returns true if the given file descriptor is a terminal.
func IsTerminal(fd int) bool {
_, err := unix.IoctlGetTermio(fd, unix.TCGETA)
return err == nil
}
// ReadPassword reads a line of input from a terminal without local echo. This
// is commonly used for inputting passwords and other sensitive data. The slice
// returned does not include the \n.
func ReadPassword(fd int) ([]byte, error) {
// see also: http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libast/common/uwin/getpass.c
val, err := unix.IoctlGetTermios(fd, unix.TCGETS)
if err != nil {
return nil, err
}
oldState := *val
newState := oldState
newState.Lflag &^= syscall.ECHO
newState.Lflag |= syscall.ICANON | syscall.ISIG
newState.Iflag |= syscall.ICRNL
err = unix.IoctlSetTermios(fd, unix.TCSETS, &newState)
if err != nil {
return nil, err
}
defer unix.IoctlSetTermios(fd, unix.TCSETS, &oldState)
var buf [16]byte
var ret []byte
for {
n, err := syscall.Read(fd, buf[:])
if err != nil {
return nil, err
}
if n == 0 {
if len(ret) == 0 {
return nil, io.EOF
}
break
}
if buf[n-1] == '\n' {
n--
}
ret = append(ret, buf[:n]...)
if n < len(buf) {
break
}
}
return ret, nil
}
// MakeRaw puts the terminal connected to the given file descriptor into raw
// mode and returns the previous state of the terminal so that it can be
// restored.
// see http://cr.illumos.org/~webrev/andy_js/1060/
func MakeRaw(fd int) (*State, error) {
oldTermiosPtr, err := unix.IoctlGetTermios(fd, unix.TCGETS)
if err != nil {
return nil, err
}
oldTermios := *oldTermiosPtr
newTermios := oldTermios
newTermios.Iflag &^= syscall.IGNBRK | syscall.BRKINT | syscall.PARMRK | syscall.ISTRIP | syscall.INLCR | syscall.IGNCR | syscall.ICRNL | syscall.IXON
newTermios.Oflag &^= syscall.OPOST
newTermios.Lflag &^= syscall.ECHO | syscall.ECHONL | syscall.ICANON | syscall.ISIG | syscall.IEXTEN
newTermios.Cflag &^= syscall.CSIZE | syscall.PARENB
newTermios.Cflag |= syscall.CS8
newTermios.Cc[unix.VMIN] = 1
newTermios.Cc[unix.VTIME] = 0
if err := unix.IoctlSetTermios(fd, unix.TCSETS, &newTermios); err != nil {
return nil, err
}
return &State{
state: oldTermiosPtr,
}, nil
}
// Restore restores the terminal connected to the given file descriptor to a
// previous state.
func Restore(fd int, oldState *State) error {
return unix.IoctlSetTermios(fd, unix.TCSETS, oldState.state)
}
// GetState returns the current state of a terminal which may be useful to
// restore the terminal after a signal.
func GetState(fd int) (*State, error) {
oldTermiosPtr, err := unix.IoctlGetTermios(fd, unix.TCGETS)
if err != nil {
return nil, err
}
return &State{
state: oldTermiosPtr,
}, nil
}
// GetSize returns the dimensions of the given terminal.
func GetSize(fd int) (width, height int, err error) {
ws, err := unix.IoctlGetWinsize(fd, unix.TIOCGWINSZ)
if err != nil {
return 0, 0, err
}
return int(ws.Col), int(ws.Row), nil
}

35
ssh/terminal/util_windows.go
View file

@ -17,7 +17,6 @@
package terminal
import (
"io"
"syscall"
"unsafe"
)
@ -123,6 +122,13 @@ func GetSize(fd int) (width, height int, err error) {
return int(info.size.x), int(info.size.y), nil
}
// passwordReader is an io.Reader that reads from a specific Windows HANDLE.
type passwordReader int
func (r passwordReader) Read(buf []byte) (int, error) {
return syscall.Read(syscall.Handle(r), buf)
}
// ReadPassword reads a line of input from a terminal without local echo. This
// is commonly used for inputting passwords and other sensitive data. The slice
// returned does not include the \n.
@ -145,30 +151,5 @@ func ReadPassword(fd int) ([]byte, error) {
syscall.Syscall(procSetConsoleMode.Addr(), 2, uintptr(fd), uintptr(old), 0)
}()
var buf [16]byte
var ret []byte
for {
n, err := syscall.Read(syscall.Handle(fd), buf[:])
if err != nil {
return nil, err
}
if n == 0 {
if len(ret) == 0 {
return nil, io.EOF
}
break
}
if buf[n-1] == '\n' {
n--
}
if n > 0 && buf[n-1] == '\r' {
n--
}
ret = append(ret, buf[:n]...)
if n < len(buf) {
break
}
}
return ret, nil
return readPasswordLine(passwordReader(fd))
}

38
ssh/test/cert_test.go
View file

@ -7,12 +7,14 @@
package test
import (
"bytes"
"crypto/rand"
"testing"
"golang.org/x/crypto/ssh"
)
// Test both logging in with a cert, and also that the certificate presented by an OpenSSH host can be validated correctly
func TestCertLogin(t *testing.T) {
s := newServer(t)
defer s.Shutdown()
@ -37,11 +39,39 @@ func TestCertLogin(t *testing.T) {
conf := &ssh.ClientConfig{
User: username(),
HostKeyCallback: (&ssh.CertChecker{
IsHostAuthority: func(pk ssh.PublicKey, addr string) bool {
return bytes.Equal(pk.Marshal(), testPublicKeys["ca"].Marshal())
},
}).CheckHostKey,
}
conf.Auth = append(conf.Auth, ssh.PublicKeys(certSigner))
client, err := s.TryDial(conf)
if err != nil {
t.Fatalf("TryDial: %v", err)
for _, test := range []struct {
addr string
succeed bool
}{
{addr: "host.example.com:22", succeed: true},
{addr: "host.example.com:10000", succeed: true}, // non-standard port must be OK
{addr: "host.example.com", succeed: false}, // port must be specified
{addr: "host.ex4mple.com:22", succeed: false}, // wrong host
} {
client, err := s.TryDialWithAddr(conf, test.addr)
// Always close client if opened successfully
if err == nil {
client.Close()
}
// Now evaluate whether the test failed or passed
if test.succeed {
if err != nil {
t.Fatalf("TryDialWithAddr: %v", err)
}
} else {
if err == nil {
t.Fatalf("TryDialWithAddr, unexpected success")
}
}
}
client.Close()
}

128
ssh/test/dial_unix_test.go Normal file
View file

@ -0,0 +1,128 @@
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !windows
package test
// direct-tcpip and direct-streamlocal functional tests
import (
"fmt"
"io"
"io/ioutil"
"net"
"strings"
"testing"
)
type dialTester interface {
TestServerConn(t *testing.T, c net.Conn)
TestClientConn(t *testing.T, c net.Conn)
}
func testDial(t *testing.T, n, listenAddr string, x dialTester) {
server := newServer(t)
defer server.Shutdown()
sshConn := server.Dial(clientConfig())
defer sshConn.Close()
l, err := net.Listen(n, listenAddr)
if err != nil {
t.Fatalf("Listen: %v", err)
}
defer l.Close()
testData := fmt.Sprintf("hello from %s, %s", n, listenAddr)
go func() {
for {
c, err := l.Accept()
if err != nil {
break
}
x.TestServerConn(t, c)
io.WriteString(c, testData)
c.Close()
}
}()
conn, err := sshConn.Dial(n, l.Addr().String())
if err != nil {
t.Fatalf("Dial: %v", err)
}
x.TestClientConn(t, conn)
defer conn.Close()
b, err := ioutil.ReadAll(conn)
if err != nil {
t.Fatalf("ReadAll: %v", err)
}
t.Logf("got %q", string(b))
if string(b) != testData {
t.Fatalf("expected %q, got %q", testData, string(b))
}
}
type tcpDialTester struct {
listenAddr string
}
func (x *tcpDialTester) TestServerConn(t *testing.T, c net.Conn) {
host := strings.Split(x.listenAddr, ":")[0]
prefix := host + ":"
if !strings.HasPrefix(c.LocalAddr().String(), prefix) {
t.Fatalf("expected to start with %q, got %q", prefix, c.LocalAddr().String())
}
if !strings.HasPrefix(c.RemoteAddr().String(), prefix) {
t.Fatalf("expected to start with %q, got %q", prefix, c.RemoteAddr().String())
}
}
func (x *tcpDialTester) TestClientConn(t *testing.T, c net.Conn) {
// we use zero addresses. see *Client.Dial.
if c.LocalAddr().String() != "0.0.0.0:0" {
t.Fatalf("expected \"0.0.0.0:0\", got %q", c.LocalAddr().String())
}
if c.RemoteAddr().String() != "0.0.0.0:0" {
t.Fatalf("expected \"0.0.0.0:0\", got %q", c.RemoteAddr().String())
}
}
func TestDialTCP(t *testing.T) {
x := &tcpDialTester{
listenAddr: "127.0.0.1:0",
}
testDial(t, "tcp", x.listenAddr, x)
}
type unixDialTester struct {
listenAddr string
}
func (x *unixDialTester) TestServerConn(t *testing.T, c net.Conn) {
if c.LocalAddr().String() != x.listenAddr {
t.Fatalf("expected %q, got %q", x.listenAddr, c.LocalAddr().String())
}
if c.RemoteAddr().String() != "@" {
t.Fatalf("expected \"@\", got %q", c.RemoteAddr().String())
}
}
func (x *unixDialTester) TestClientConn(t *testing.T, c net.Conn) {
if c.RemoteAddr().String() != x.listenAddr {
t.Fatalf("expected %q, got %q", x.listenAddr, c.RemoteAddr().String())
}
if c.LocalAddr().String() != "@" {
t.Fatalf("expected \"@\", got %q", c.LocalAddr().String())
}
}
func TestDialUnix(t *testing.T) {
addr, cleanup := newTempSocket(t)
defer cleanup()
x := &unixDialTester{
listenAddr: addr,
}
testDial(t, "unix", x.listenAddr, x)
}

62
ssh/test/forward_unix_test.go
View file

@ -16,13 +16,17 @@ import (
"time"
)
func TestPortForward(t *testing.T) {
type closeWriter interface {
CloseWrite() error
}
func testPortForward(t *testing.T, n, listenAddr string) {
server := newServer(t)
defer server.Shutdown()
conn := server.Dial(clientConfig())
defer conn.Close()
sshListener, err := conn.Listen("tcp", "localhost:0")
sshListener, err := conn.Listen(n, listenAddr)
if err != nil {
t.Fatal(err)
}
@ -41,14 +45,14 @@ func TestPortForward(t *testing.T) {
}()
forwardedAddr := sshListener.Addr().String()
tcpConn, err := net.Dial("tcp", forwardedAddr)
netConn, err := net.Dial(n, forwardedAddr)
if err != nil {
t.Fatalf("TCP dial failed: %v", err)
t.Fatalf("net dial failed: %v", err)
}
readChan := make(chan []byte)
go func() {
data, _ := ioutil.ReadAll(tcpConn)
data, _ := ioutil.ReadAll(netConn)
readChan <- data
}()
@ -62,14 +66,14 @@ func TestPortForward(t *testing.T) {
for len(sent) < 1000*1000 {
// Send random sized chunks
m := rand.Intn(len(data))
n, err := tcpConn.Write(data[:m])
n, err := netConn.Write(data[:m])
if err != nil {
break
}
sent = append(sent, data[:n]...)
}
if err := tcpConn.(*net.TCPConn).CloseWrite(); err != nil {
t.Errorf("tcpConn.CloseWrite: %v", err)
if err := netConn.(closeWriter).CloseWrite(); err != nil {
t.Errorf("netConn.CloseWrite: %v", err)
}
read := <-readChan
@ -86,19 +90,29 @@ func TestPortForward(t *testing.T) {
}
// Check that the forward disappeared.
tcpConn, err = net.Dial("tcp", forwardedAddr)
netConn, err = net.Dial(n, forwardedAddr)
if err == nil {
tcpConn.Close()
netConn.Close()
t.Errorf("still listening to %s after closing", forwardedAddr)
}
}
func TestAcceptClose(t *testing.T) {
func TestPortForwardTCP(t *testing.T) {
testPortForward(t, "tcp", "localhost:0")
}
func TestPortForwardUnix(t *testing.T) {
addr, cleanup := newTempSocket(t)
defer cleanup()
testPortForward(t, "unix", addr)
}
func testAcceptClose(t *testing.T, n, listenAddr string) {
server := newServer(t)
defer server.Shutdown()
conn := server.Dial(clientConfig())
sshListener, err := conn.Listen("tcp", "localhost:0")
sshListener, err := conn.Listen(n, listenAddr)
if err != nil {
t.Fatal(err)
}
@ -124,13 +138,23 @@ func TestAcceptClose(t *testing.T) {
}
}
func TestAcceptCloseTCP(t *testing.T) {
testAcceptClose(t, "tcp", "localhost:0")
}
func TestAcceptCloseUnix(t *testing.T) {
addr, cleanup := newTempSocket(t)
defer cleanup()
testAcceptClose(t, "unix", addr)
}
// Check that listeners exit if the underlying client transport dies.
func TestPortForwardConnectionClose(t *testing.T) {
func testPortForwardConnectionClose(t *testing.T, n, listenAddr string) {
server := newServer(t)
defer server.Shutdown()
conn := server.Dial(clientConfig())
sshListener, err := conn.Listen("tcp", "localhost:0")
sshListener, err := conn.Listen(n, listenAddr)
if err != nil {
t.Fatal(err)
}
@ -158,3 +182,13 @@ func TestPortForwardConnectionClose(t *testing.T) {
t.Logf("quit as expected (error %v)", err)
}
}
func TestPortForwardConnectionCloseTCP(t *testing.T) {
testPortForwardConnectionClose(t, "tcp", "localhost:0")
}
func TestPortForwardConnectionCloseUnix(t *testing.T) {
addr, cleanup := newTempSocket(t)
defer cleanup()
testPortForwardConnectionClose(t, "unix", addr)
}

46
ssh/test/tcpip_test.go
View file

@ -1,46 +0,0 @@
// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !windows
package test
// direct-tcpip functional tests
import (
"io"
"net"
"testing"
)
func TestDial(t *testing.T) {
server := newServer(t)
defer server.Shutdown()
sshConn := server.Dial(clientConfig())
defer sshConn.Close()
l, err := net.Listen("tcp", "127.0.0.1:0")
if err != nil {
t.Fatalf("Listen: %v", err)
}
defer l.Close()
go func() {
for {
c, err := l.Accept()
if err != nil {
break
}
io.WriteString(c, c.RemoteAddr().String())
c.Close()
}
}()
conn, err := sshConn.Dial("tcp", l.Addr().String())
if err != nil {
t.Fatalf("Dial: %v", err)
}
defer conn.Close()
}

29
ssh/test/test_unix_test.go
View file

@ -30,6 +30,7 @@ Protocol 2
HostKey {{.Dir}}/id_rsa
HostKey {{.Dir}}/id_dsa
HostKey {{.Dir}}/id_ecdsa
HostCertificate {{.Dir}}/id_rsa-cert.pub
Pidfile {{.Dir}}/sshd.pid
#UsePrivilegeSeparation no
KeyRegenerationInterval 3600
@ -119,6 +120,11 @@ func clientConfig() *ssh.ClientConfig {
ssh.PublicKeys(testSigners["user"]),
},
HostKeyCallback: hostKeyDB().Check,
HostKeyAlgorithms: []string{ // by default, don't allow certs as this affects the hostKeyDB checker
ssh.KeyAlgoECDSA256, ssh.KeyAlgoECDSA384, ssh.KeyAlgoECDSA521,
ssh.KeyAlgoRSA, ssh.KeyAlgoDSA,
ssh.KeyAlgoED25519,
},
}
return config
}
@ -154,6 +160,12 @@ func unixConnection() (*net.UnixConn, *net.UnixConn, error) {
}
func (s *server) TryDial(config *ssh.ClientConfig) (*ssh.Client, error) {
return s.TryDialWithAddr(config, "")
}
// addr is the user specified host:port. While we don't actually dial it,
// we need to know this for host key matching
func (s *server) TryDialWithAddr(config *ssh.ClientConfig, addr string) (*ssh.Client, error) {
sshd, err := exec.LookPath("sshd")
if err != nil {
s.t.Skipf("skipping test: %v", err)
@ -179,7 +191,7 @@ func (s *server) TryDial(config *ssh.ClientConfig) (*ssh.Client, error) {
s.t.Fatalf("s.cmd.Start: %v", err)
}
s.clientConn = c1
conn, chans, reqs, err := ssh.NewClientConn(c1, "", config)
conn, chans, reqs, err := ssh.NewClientConn(c1, addr, config)
if err != nil {
return nil, err
}
@ -250,6 +262,11 @@ func newServer(t *testing.T) *server {
writeFile(filepath.Join(dir, filename+".pub"), ssh.MarshalAuthorizedKey(testPublicKeys[k]))
}
for k, v := range testdata.SSHCertificates {
filename := "id_" + k + "-cert.pub"
writeFile(filepath.Join(dir, filename), v)
}
var authkeys bytes.Buffer
for k, _ := range testdata.PEMBytes {
authkeys.Write(ssh.MarshalAuthorizedKey(testPublicKeys[k]))
@ -266,3 +283,13 @@ func newServer(t *testing.T) *server {
},
}
}
func newTempSocket(t *testing.T) (string, func()) {
dir, err := ioutil.TempDir("", "socket")
if err != nil {
t.Fatal(err)
}
deferFunc := func() { os.RemoveAll(dir) }
addr := filepath.Join(dir, "sock")
return addr, deferFunc
}

120
ssh/testdata/keys.go vendored
View file

@ -48,10 +48,130 @@ AAAEAaYmXltfW6nhRo3iWGglRB48lYq0z0Q3I3KyrdutEr6j7d/uFLuDlRbBc4ZVOsx+Gb
HKuOrPtLHFvHsjWPwO+/AAAAE2dhcnRvbm1AZ2FydG9ubS14cHMBAg==
-----END OPENSSH PRIVATE KEY-----
`),
"rsa-openssh-format": []byte(`-----BEGIN OPENSSH PRIVATE KEY-----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-----END OPENSSH PRIVATE KEY-----`),
"user": []byte(`-----BEGIN EC PRIVATE KEY-----
MHcCAQEEILYCAeq8f7V4vSSypRw7pxy8yz3V5W4qg8kSC3zJhqpQoAoGCCqGSM49
AwEHoUQDQgAEYcO2xNKiRUYOLEHM7VYAp57HNyKbOdYtHD83Z4hzNPVC4tM5mdGD
PLL8IEwvYu2wq+lpXfGQnNMbzYf9gspG0w==
-----END EC PRIVATE KEY-----
`),
"ca": []byte(`-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
`),
}
var SSHCertificates = map[string][]byte{
// The following are corresponding certificates for the private keys above, signed by the CA key
// Generated by the following commands:
//
// 1. Assumes "rsa" key above in file named "rsa", write out the public key to "rsa.pub":
// ssh-keygen -y -f rsa > rsa.pu
//
// 2. Assumes "ca" key above in file named "ca", sign a cert for "rsa.pub":
// ssh-keygen -s ca -h -n host.example.com -V +500w -I host.example.com-key rsa.pub
"rsa": []byte(`ssh-rsa-cert-v01@openssh.com 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 host.example.com
`),
}
var PEMEncryptedKeys = []struct {
Name string
EncryptionKey string
PEMBytes []byte
}{
0: {
Name: "rsa-encrypted",
EncryptionKey: "r54-G0pher_t3st$",
PEMBytes: []byte(`-----BEGIN RSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-128-CBC,3E1714DE130BC5E81327F36564B05462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-----END RSA PRIVATE KEY-----
`),
},
1: {
Name: "dsa-encrypted",
EncryptionKey: "qG0pher-dsa_t3st$",
PEMBytes: []byte(`-----BEGIN DSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-128-CBC,7CE7A6E4A647DC01AF860210B15ADE3E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-----END DSA PRIVATE KEY-----
`),
},
}

50
ssh/transport.go
View file

@ -8,8 +8,13 @@ import (
"bufio"
"errors"
"io"
"log"
)
// debugTransport if set, will print packet types as they go over the
// wire. No message decoding is done, to minimize the impact on timing.
const debugTransport = false
const (
gcmCipherID = "aes128-gcm@openssh.com"
aes128cbcID = "aes128-cbc"
@ -22,7 +27,9 @@ type packetConn interface {
// Encrypt and send a packet of data to the remote peer.
writePacket(packet []byte) error
// Read a packet from the connection
// Read a packet from the connection. The read is blocking,
// i.e. if error is nil, then the returned byte slice is
// always non-empty.
readPacket() ([]byte, error)
// Close closes the write-side of the connection.
@ -38,7 +45,7 @@ type transport struct {
bufReader *bufio.Reader
bufWriter *bufio.Writer
rand io.Reader
isClient bool
io.Closer
}
@ -84,9 +91,38 @@ func (t *transport) prepareKeyChange(algs *algorithms, kexResult *kexResult) err
return nil
}
func (t *transport) printPacket(p []byte, write bool) {
if len(p) == 0 {
return
}
who := "server"
if t.isClient {
who = "client"
}
what := "read"
if write {
what = "write"
}
log.Println(what, who, p[0])
}
// Read and decrypt next packet.
func (t *transport) readPacket() ([]byte, error) {
return t.reader.readPacket(t.bufReader)
func (t *transport) readPacket() (p []byte, err error) {
for {
p, err = t.reader.readPacket(t.bufReader)
if err != nil {
break
}
if len(p) == 0 || (p[0] != msgIgnore && p[0] != msgDebug) {
break
}
}
if debugTransport {
t.printPacket(p, false)
}
return p, err
}
func (s *connectionState) readPacket(r *bufio.Reader) ([]byte, error) {
@ -129,6 +165,9 @@ func (s *connectionState) readPacket(r *bufio.Reader) ([]byte, error) {
}
func (t *transport) writePacket(packet []byte) error {
if debugTransport {
t.printPacket(packet, true)
}
return t.writer.writePacket(t.bufWriter, t.rand, packet)
}
@ -169,6 +208,8 @@ func newTransport(rwc io.ReadWriteCloser, rand io.Reader, isClient bool) *transp
},
Closer: rwc,
}
t.isClient = isClient
if isClient {
t.reader.dir = serverKeys
t.writer.dir = clientKeys
@ -226,6 +267,7 @@ func newPacketCipher(d direction, algs directionAlgorithms, kex *kexResult) (pac
c := &streamPacketCipher{
mac: macModes[algs.MAC].new(macKey),
etm: macModes[algs.MAC].etm,
}
c.macResult = make([]byte, c.mac.Size())

7
sshpiperd/workingdir.go
View file

@ -29,9 +29,10 @@ var (
)
func init() {
// http://stackoverflow.com/questions/6949667/what-are-the-real-rules-for-linux-usernames-on-centos-6-and-rhel-6
// #NAME_REGEX="^[a-z][-a-z0-9_]*\$"
usernameRule, _ = regexp.Compile("^[a-z_][a-z0-9_]{0,30}$")
// Base username validation on Debians default: https://sources.debian.net/src/adduser/3.113%2Bnmu3/adduser.conf/#L85
// -> NAME_REGEX="^[a-z][-a-z0-9_]*\$"
// The length is limited to 32 characters. See man 8 useradd: https://linux.die.net/man/8/useradd
usernameRule, _ = regexp.Compile("^[a-z_][-a-z0-9_]{0,31}$")
}
func userSpecFile(user, file string) string {

2
ver
View file

@ -1 +1 @@
v0.2
v0.3.dev