Kerberos auth, StartTLS, channel binding, --debug, Python 3.13 fixes - #86
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bandrel wants to merge 30 commits into
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Kerberos auth, StartTLS, channel binding, --debug, Python 3.13 fixes#86bandrel wants to merge 30 commits into
bandrel wants to merge 30 commits into
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Design spec for ccache-only Kerberos authentication via impacket, plus LDAP signing fix for strongerAuthRequired on hardened DCs, and StartTLS support for environments without LDAPS. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Nine-task TDD plan covering auth refactor, NTLM sign/seal fix, SIMPLE error improvement, TLS verify flag, StartTLS, Kerberos CLI, Kerberos bind via impacket+raw SASL, and README updates. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
No behavior change. Moves NTLM/SIMPLE bind logic out of main() into build_connection(args). Groundwork for Kerberos support and LDAP signing fixes.
Adds a regression guard verifying that build_connection passes no user, password, or authentication kwargs to Connection when args.user is None. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Modern AD DCs reject unsigned binds on plain LDAP with strongerAuthRequired (code 8). NTLM session_security=ENCRYPT negotiates sign/seal and is a no-op over TLS. Note: ldap3 2.x (latest 2.9.1) does not export ENCRYPT; the constant is defined locally in auth.py as a sentinel. When ldap3 gains native ENCRYPT support this can be swapped to a direct import.
…irement" This reverts commit b909be1.
ldap3 2.9.1 has no NTLM signing support (no ENCRYPT constant, no session_security kwarg on Connection). Verified via introspection. Implementing it would require a library swap or heavy monkey-patching, both out of scope. Task 3 is skipped; Task 4 gains an NTLM-specific error message pointing users at the three working signing paths: Kerberos, LDAPS, StartTLS. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
For SIMPLE and NTLM binds rejected with code 8 on hardened DCs, surface an auth-type-specific message pointing at Kerberos / LDAPS / StartTLS — the three signing paths that actually work. ldap3 2.9.1 does not support NTLM sign/seal, so we guide users to working alternatives instead of dumping the raw LDAP result dict.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Introduces _build_server() helper and --no-tls-verify escape hatch for self-signed DC certificates. Extracts argparse into _build_parser() so CLI-level tests can exercise it without invoking main().
…d test Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Supports environments where port 636 is firewalled. Argparse rejects --start-tls with ldaps:// URLs via _validate_args. Bind helpers now explicitly open() -> maybe start_tls() -> bind().
Previously _open_and_maybe_start_tls silently discarded the boolean return of Connection.open() and Connection.start_tls(). A failed StartTLS upgrade would fall through to a plaintext bind — a silent downgrade of the very security guarantee the user requested. Both return values are now checked and surfaced as AuthError.
…tions Adds BloodHound.py-style authentication flags including Kerberos (-k), hashes (--hashes), AES key (-aesKey), auth method (--auth-method), domain, and LDAP channel binding. Replaces -at/--authtype with --auth-method that defaults to 'auto' for Kerberos-first behavior. Changes -u/--user to -u/--username for consistency with impacket conventions. Adds -no-pass flag for non-interactive auth scenarios. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
- Reject -k with --auth-method ntlm (incompatible) - Reject -k without username (anonymous Kerberos unsupported) - Reject --auth-method kerberos without username - Imply --auth-method kerberos when -k is passed with valid username Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Adds 5 methods to ADAuthentication class: - _kerberos_usable() checks if Kerberos credentials are available - _kerberos_forced() returns True when ccache is in use (no fallback) - _ensure_tgt() populates self.tgt from ccache or AS-REQ - _ntlm_login() formats the domain\username string for NTLM bind - authenticate() orchestrates the full auth flow: Kerberos first, then NTLM/anonymous fallback with proper error handling and channel binding Implements Kerberos-first strategy with graceful fallback to NTLM when auto mode is used. Validates auth_method to prevent unexpected code paths. Adds 9 tests covering: - Kerberos usability checks (username, password, ccache paths) - Forced vs optional fallback logic - Anonymous, NTLM, and Kerberos bind paths - Channel binding validation and error messages - Safety check for auth_method='kerberos' fallthrough All 50 tests pass (29 auth + 21 CLI). Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
…mpt helper - Rewrite auth.py: ADAuthentication wires into build_connection(args), UPN username parsing, down-level rejection, FQDN enforcement for Kerberos - Extract _prompt_password_if_needed() from main(); -k and -no-pass suppress getpass - Replace old test_auth.py with 13 new tests covering dispatcher surface - Add 3 test_cli.py tests for password prompt logic - All 67 tests pass; entry point imports verified Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Mainline ldap3 lacks NTLM sign/seal and channel binding support, both needed against modern AD with LDAP signing required. Python 3.13's hashlib also dropped MD4, which ldap3's NTLM path needs via Crypto.Hash.MD4 from pycryptodome. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
The --start-tls CLI flag existed but was never honored. Plumb it through ADAuthentication and run StartTLS on the open socket before bind, for both Kerberos and NTLM paths. ldap_kerberos previously called connection.open() unconditionally; ldap3 treats that as a re-open and tears down the existing socket, which would discard our StartTLS wrap. Guard it with `if connection.closed`. Also surface the swallowed AuthError detail when Kerberos falls back to NTLM, to make misconfigurations debuggable. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Configures root logging at DEBUG and bumps ldap3's library log detail to EXTENDED so the auth flow (Kerberos referrals, NTLM negotiation, TLS) can be traced when binds misbehave. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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clock skew means your clock is off. Try to update your time on your client to match the time on the DC |
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Summary
Adds Kerberos authentication and several closely related auth/UX features needed to operate against modern AD where NTLM is disabled or LDAP signing is enforced. Implements the work proposed in #82, #83, #84, #85.
Authentication
-k,-aesKey,--auth-method,--domain) — TGT fromKRB5CCNAME, AES key auth, cross-realm referral walk, graceful NTLM fallback underauto. Ported (with pruning) from BloodHound.py's auth module — fixes Add Kerberos authentication support (-k, ccache, AES key, channel binding) #82--ldap-channel-binding) — RFC 5929tls-server-end-pointfor both NTLM and Kerberos GSS — part of Add Kerberos authentication support (-k, ccache, AES key, channel binding) #82TLS_CHANNEL_BINDING) and addspycryptodome(Python 3.13 dropped MD4 fromhashlib) — fixes NTLM bind broken on Python 3.13 (MD4 removed) and against signing-required DCs #85CLI / UX
--start-tls— upgrade plain LDAP to TLS before bind; composes with--no-tls-verifyand all auth methods. Includes a guard in the Kerberos path soConnection.open()doesn't tear down the StartTLS-wrapped socket — fixes Add --start-tls to upgrade plain LDAP to TLS before bind #83--debug— verbose auth flow + ldap3EXTENDEDlogging — fixes Add --debug for verbose auth + ldap3 logging #84Dependencies
ldap3is pinned to the ly4k fork inpyproject.toml. Open to switching to a soft dependency / runtime check if you'd prefer not to vendor a fork by default — happy to rework however you'd like.Test plan
-kagainst a DC using a TGT fromKRB5CCNAME-kcross-realm (user in trusted realm)-aesKeyAES auth--auth-method ntlmagainst a DC requiring signing (with ly4k fork)--start-tlswith NTLM and with Kerberos--ldap-channel-bindingagainst ldaps:// and StartTLS--debugproduces ldap3 EXTENDED logs🤖 Generated with Claude Code