import java.util.*;
import java.util.regex.*;

/**
 * Unit test for squid-0003: CWE-312 - FTP and Basic auth credentials logged
 * verbatim in debug output.
 *
 * Affected files:
 *   src/clients/FtpGateway.cc  - loginParser() logs user:password at debug 9
 *   src/auth/basic/Config.cc   - decodeCleartext() logs cleartext at debug 9,
 *                                logs Authorization header at DBG_IMPORTANT (level 1)
 *   src/auth/basic/UserRequest.cc - startHelperLookup() logs user:password at debug 9
 *
 * CWE-312: Cleartext Storage of Sensitive Information.
 * When an operator enables "debug_options 9,9" (or even "29,4"), plaintext
 * FTP passwords and decoded Basic auth credentials land in cache.log.
 *
 * Fix: Replace credential values with redacted markers in all debug statements.
 */
public class SquidCredentialLogTest {

    // Simulate the defect: credential fields emitted in log messages
    static String loginParserLogDefect(String login, String user, String password) {
        // FtpGateway.cc line 402
        return "IN : login=" + login + ", user=" + user + ", password=" + password;
    }

    static String basicDecodeLogDefect(String cleartext) {
        // basic/Config.cc line 188
        return "'" + cleartext + "'";
    }

    static String basicHelperLogDefect(String username, String passwd) {
        // basic/UserRequest.cc line 105
        return "'" + username + ":" + passwd + "'";
    }

    // Simulate the fix: redacted log messages
    static String loginParserLogFix(String login, String user, String password) {
        return "IN : login=[REDACTED], user=[user], password=[REDACTED]";
    }

    static String basicDecodeLogFix(String cleartext) {
        return "decoded basic credentials (length " + cleartext.length() + ")";
    }

    static String basicHelperLogFix(String username, String passwd) {
        return "looking up basic auth user '" + username + "' (password suppressed)";
    }

    // Pattern to detect credential exposure in a log line
    static boolean containsCredential(String logLine, String password) {
        return logLine.contains(password);
    }

    static boolean containsUsername(String logLine, String username) {
        return logLine.contains(username + ":");
    }

    public static void main(String[] args) {
        System.out.println("=== squid-0003: CWE-312 credential logging in FTP and Basic auth ===");
        System.out.println();

        String ftpUser     = "ftpuser";
        String ftpPassword = "s3cr3t!FTP";
        String ftpLogin    = ftpUser + ":" + ftpPassword;

        String basicUser   = "proxyuser";
        String basicPass   = "myP@ssw0rd";
        String cleartext   = basicUser + ":" + basicPass;

        // --- Defect verification: passwords ARE in log lines ---
        String defectFtpLog    = loginParserLogDefect(ftpLogin, ftpUser, ftpPassword);
        String defectDecodeLog = basicDecodeLogDefect(cleartext);
        String defectHelperLog = basicHelperLogDefect(basicUser, basicPass);

        assert containsCredential(defectFtpLog, ftpPassword) :
            "Defect FTP log should contain password";
        assert containsCredential(defectDecodeLog, basicPass) :
            "Defect decode log should contain password";
        assert containsCredential(defectHelperLog, basicPass) :
            "Defect helper log should contain password";
        assert containsUsername(defectHelperLog, basicUser) :
            "Defect helper log should contain user:pass pattern";

        System.out.println("Defect confirmed: passwords present in log lines");
        System.out.println("  FTP log:    " + defectFtpLog);
        System.out.println("  Decode log: " + defectDecodeLog);
        System.out.println("  Helper log: " + defectHelperLog);
        System.out.println();

        // --- Fix verification: passwords NOT in log lines ---
        String fixFtpLog    = loginParserLogFix(ftpLogin, ftpUser, ftpPassword);
        String fixDecodeLog = basicDecodeLogFix(cleartext);
        String fixHelperLog = basicHelperLogFix(basicUser, basicPass);

        assert !containsCredential(fixFtpLog, ftpPassword) :
            "Fix FTP log must NOT contain password, got: " + fixFtpLog;
        assert !containsCredential(fixDecodeLog, basicPass) :
            "Fix decode log must NOT contain password, got: " + fixDecodeLog;
        assert !containsCredential(fixHelperLog, basicPass) :
            "Fix helper log must NOT contain password, got: " + fixHelperLog;
        assert !containsUsername(fixHelperLog, basicUser) :
            "Fix helper log must NOT contain user:pass pattern, got: " + fixHelperLog;

        // Fix logs must still be useful (contain non-sensitive context)
        assert fixFtpLog.contains("[REDACTED]") :
            "Fix FTP log should show redaction marker";
        assert fixDecodeLog.contains("length") :
            "Fix decode log should include length info for diagnostics";
        assert fixHelperLog.contains(basicUser) && fixHelperLog.contains("suppressed") :
            "Fix helper log should show username (not secret) and suppression note";

        System.out.println("Fix verified: no passwords in redacted log lines");
        System.out.println("  FTP log:    " + fixFtpLog);
        System.out.println("  Decode log: " + fixDecodeLog);
        System.out.println("  Helper log: " + fixHelperLog);
        System.out.println();

        // --- Severity: DBG_IMPORTANT path (level 1, always logged) ---
        // basic/Config.cc:191 logs Authorization header at DBG_IMPORTANT when
        // bad characters are detected - this fires even without debug_options tuning
        String authHeader = "Basic " + Base64.getEncoder().encodeToString(cleartext.getBytes());
        String defectImportantLog = "WARNING: Bad characters in authorization header '" + authHeader + "'";
        String fixImportantLog    = "WARNING: Bad characters in Basic authorization header (base64 header suppressed for security)";

        assert defectImportantLog.contains(authHeader) :
            "Defect important log should contain auth header";
        assert !fixImportantLog.contains(authHeader) :
            "Fix important log must NOT contain auth header";

        System.out.println("DBG_IMPORTANT path: PASS");
        System.out.println("  Defect: " + defectImportantLog);
        System.out.println("  Fix:    " + fixImportantLog);
        System.out.println();

        System.out.println("=== squid-0003 PASS ===");
    }
}