Phase 2/3 of DEBT-039. Switches FTP, POP3, IMAP, SMTP, Redis, and
LDAP from the legacy `username=` + `password=` SD-block shape to the
universal credential shape (`principal=` + `secret_printable=` +
`secret_b64=`) the new Credential storage model expects.
Pattern is uniform across all six services:
_log("auth_attempt", username=u, principal=u, **encode_secret(pw))
Each service emits the canonical SD keys. The ingester's native-shape
branch (introduced in 2f47f67) now writes their cred attempts
directly without going through the legacy adapter. Once Phase 3
removes the adapter the contract becomes single-shape.
Per-service notes:
- POP3 / IMAP — `status="success"|"failed"` renamed to
`outcome="success"|"failure"` to match Credential.outcome's
vocabulary; the ingester reads outcome directly.
- SMTP — AUTH path migrated; in addition the existing mail_from
event now exposes a parsed `domain=` field alongside the original
`value=` so future "what domains do attackers spoof from" analytics
have an indexed field. Not stored in Credential — regular Log row.
- Redis — was silently dropped by the legacy adapter (no `username`
field). Native branch handles `principal=None` correctly. BONUS
FIX: the Redis 6+ ACL syntax `AUTH <user> <pw>` now captures the
ACL username as principal (was previously discarded).
- LDAP — was silently dropped by the legacy adapter (no `password`
recognition for the `bind` event). Now lands as
`principal=<dn>`. BONUS FIX.
Tests (tests/services/test_cred_emitters.py, 9 cases):
- per-service native-shape ingest path produces correct Credential
rows; outcome maps for POP3/IMAP; principal=None for legacy Redis
AUTH; principal=dn for LDAP.
- mail_from event does NOT trigger a credential write (it's a
Log-only observation, not auth).
- 0xff/NUL/ANSI bytes in passwords survive losslessly through
secret_b64 even when secret_printable is sanitized.
Phase 3 deletes the legacy adapter once all migrations land — the
adapter has no live emitters to handle anymore.
Phase 1/3 of DEBT-039. Adds the Python emitter-side counterpart to
auth-helper.c's sd_escape + base64 logic so service templates can
emit the universal credential SD shape with a single spread:
_log("auth_attempt", principal=user, **encode_secret(password))
secret_printable mirrors the C helper's [0x20, 0x7f) → '?' contract;
secret_b64 preserves the ORIGINAL utf-8 bytes losslessly so non-ASCII
or control-byte payloads survive as fingerprinting signal even when
the printable form sanitizes them.
The canonical syslog_bridge.py is what _sync_logging_helper()
propagates into per-template build contexts at deploy time, so any
service that imports its local syslog_bridge picks this up
automatically on next rebuild.
Phase 2 migrates the six cred-emitting service templates (FTP, POP3,
IMAP, SMTP, Redis, LDAP) onto this helper. Phase 3 deletes the
ingester's legacy adapter once nothing emits the old shape.
Replaces the opaque Bounty.bounty_type='credential' path with a
dedicated `credentials` table whose schema is forward-compatible
across every auth-bearing service in the fleet. Hoisted indexed
columns (secret_sha256, principal, service, attacker_ip) carry the
universal reuse-analytics signal; service-specific JSON keys ride
in `fields`. Cross-service reuse queries become an indexed lookup
on secret_sha256 instead of JSON_EXTRACT scans.
Schema decisions baked in (per ANTI):
- New `Credential` table, not extension to Bounty
- Hoisted `principal` column for cross-service principal-reuse
- Standardized JSON keys: every payload carries secret_b64 +
secret_printable + principal universally; service-specific extras
(user, domain, dn, mech, …) ride alongside
The auth-helper SD-block emits the new shape natively. The ingester
forks at _extract_bounty:
- Native shape (SSH/Telnet, future emitters): secret_b64 present →
direct upsert_credential
- Legacy shape (FTP/POP3/IMAP/SMTP today): username + password →
adapter synthesizes secret_{b64,sha256,printable} on the fly,
upserts into the same Credential table. Tracked as DEBT-039;
one-shot bridge until those service templates migrate.
Defense-in-depth across five layers (input validation):
- C helper: bytes outside [0x20, 0x7f) collapse to '?', RFC 5424
escape rules for \\, ", ]; b64 preserves exact bytes
- Ingester native branch: rejects malformed secret_b64 (regex), drops
the credential row but keeps the underlying Log
- Ingester legacy adapter: same printable-ASCII filter as the C
code; sha256 + b64 over the original utf-8 bytes (lossless, even
when secret_printable is sanitized)
- DB column caps with truncation warning; sha256 always over the
full pre-truncation bytes so reuse queries match across truncation
- JSON serialized with ensure_ascii=True so utf8mb4 columns stay
safe even with non-ASCII service-specific keys
Bounty.bounty_type='credential' is no longer written. Pre-v1: no
historical backfill; existing rows stay untouched but unused.
595 tests pass; new tests cover the model + repo (upsert dedup,
null-principal independence, cross-service reuse, filters), both
ingester branches, b64 validation, sanitization preserving the
fingerprinting signal in b64.
Promotes auth-helper.c to decnet/templates/_shared/auth-helper/ and
adds _sync_auth_helper_sources() — mirrors the existing sessrec sync
pattern that keeps shared sources in step with per-template build
contexts.
Telnet's image grows the same multi-stage musl build, COPY of the
static helper into /usr/sbin/auth-helper, and prepended pam_exec line
in /etc/pam.d/login. Pulls in the `login` package (real Debian
PAM-aware /bin/login, replacing busybox's PAM-less applet) and
libpam-modules transitively for pam_exec.so.
Verified inside the rebuilt telnet image:
- /bin/login is the real 53KB Debian binary (PAM-aware)
- /etc/pam.d/login top line is the auth-helper hook
- pam_exec.so present at /usr/lib/x86_64-linux-gnu/security/pam_exec.so
- helper smoke-run emits correct RFC 5424 line for `telnetpw` →
password_b64="dGVsbmV0cHc="
SSH Dockerfile updated to read auth-helper.c from auth-helper/
subdirectory so both templates use the synced layout. The canonical
source lives in _shared/; per-template copies are tracked in git AND
synced at deploy time so a drift on either side rebases on the next
deploy.
Closes the telnet half of DEBT-038's #5 follow-up.
Real OpenSSH doesn't log attempted passwords — only success/failure
with username — leaving SSH the sole auth-bearing service in the
fleet that contributes nothing to the cred corpus FTP/MySQL/RDP/
VNC/etc. populate. Closes that gap with a tiny pam_exec shim.
A static C helper (~80 LoC, musl, ~38KB stripped) is wired into
/etc/pam.d/sshd as `auth optional pam_exec.so expose_authtok stdout
/usr/sbin/auth-helper`. pam_exec writes the attempted password to
the helper's stdin NUL-terminated; the helper formats an RFC 5424
line in the exact shape templates/syslog_bridge.py produces
(facility local0, PEN 55555, MSGID auth_attempt — same MSGID FTP
uses) and writes it to /proc/1/fd/1 so the existing collector
stdout-reader pipeline picks it up.
Two password fields ride in the SD-block:
- password= RFC 5424 escaped, ASCII-printable only, ? for non-
printables. FTP-compatible — existing dashboard
rendering picks up SSH attempts unchanged.
- password_b64= base64 of the exact PAM_AUTHTOK bytes. Preserves
NUL/0xff/control-byte fingerprinting signal that the
plain field necessarily drops.
Fail-open by design: the PAM line is `optional` so a malfunctioning
helper never blocks sshd auth. Better to miss a cred than break the
honeypot.
Verified end-to-end inside the rebuilt image:
- 38KB static ELF, runs without a dynamic linker
- correct RFC 5424 line for `hunter2` → b64 `aHVudGVyMg==`
- NUL truncation matches pam_exec's contract
- 0xff bytes survive losslessly through password_b64
- empty password produces a well-formed line (e.g. pubkey auth path)
Adds instance_seed.py to every service template (conpot, docker_api,
imap, k8s, llmnr, pop3, rdp, sip, smb, snmp, ssh, telnet, tftp, vnc).
Derives a stable per-instance seed from NODE_NAME (+ optional
INSTANCE_ID) and exposes deterministic helpers for the boring details
scanners would otherwise use to fingerprint the whole fleet as one
machine: cluster UUIDs, auth salts, uptime fixtures, minor version
strings. Connection-time jitter is intentionally NOT seeded — two hits
to the same decky must not replay the same latency curve.
Identical source across every template; lives next to each service so
the Docker build context picks it up without a shared package-data hop.
SMTP template now writes each accepted DATA body as a .eml file into a
bind-mounted per-decky quarantine dir and emits a `message_stored` log
with sha256, size, decoded headers, and an attachment manifest
(filename + sha256 + size + content-type). Attachment hashing uses the
*decoded* payload so operators can match against VT / MalwareBazaar
directly. Body accumulator is capped at SMTP_MAX_BODY_BYTES (default
10 MB, matching the EHLO SIZE advert) so a streaming client can't OOM
the container.
The existing /api/v1/artifacts/{decky}/{stored_as} endpoint now takes
an optional ?service= query param (defaults to ssh for back-compat)
and can serve .eml files out of the smtp subdir. Forensic metadata
rides the normal log pipeline, same as SSH file_captured.
Every service template now pulls version strings, cluster/node UUIDs, auth
salts, greeting banners, and uptime from the seeded per-instance RNG instead
of hard-coded defaults. Scanners sweeping the fleet now see legitimately
diverging fingerprints per decky while each decky's own responses stay
internally consistent across restarts.
Covers elasticsearch, ftp, http, https, ldap, mongodb, mqtt, mssql, mysql,
postgres, redis, and smtp templates.
Each decky now gets a deterministic-per-instance seeded RNG derived from
NODE_NAME, so cluster UUIDs, version strings, uptime, and credentials diverge
across the fleet while staying stable within one container. The canonical
helper lives at decnet/templates/instance_seed.py; the deployer copies it into
every active template build context alongside syslog_bridge.py. Dockerfiles
COPY it to /opt/ so server.py can import it.
Connection-time jitter intentionally stays unseeded — two hits to the same
decky must not replay the same latency curve.
Build login-session into both images as the swapped root shell, add a
quarantine bind mount for telnet (symmetric to SSH), seed transcripts/
dir and service discriminant at entrypoint. Deployer syncs sessrec.c +
Makefile into each build context alongside the existing syslog_bridge
helper. sessrec falls back to /etc/sessrec.service when env is stripped
(busybox /bin/login).
New decnet/templates/_shared/sessrec/ — a small C program installed as the
login shell in SSH / Telnet deckies. Forkpty-relays /bin/bash, records each
chunk as an asciinema v2 event into a shared JSONL day-shard keyed by sid,
and emits one RFC 5424 session_recorded line on exit (direct to PID 1's
stdout, same pattern syslog_bridge.py uses).
Storage: one shard per (decky, UTC day) at
/var/lib/systemd/coredump/transcripts/sessions-YYYY-MM-DD.jsonl. Concurrent
appends are lock-free: each write is chunked below PIPE_BUF so O_APPEND
interleaves atomically. Per-session cap 10 MB with a trunc sentinel; disk-
free precheck (<200 MB) falls through to plain bash with a session_skipped
log event. Attacker src_ip resolves from \$SSH_CONNECTION, getpeername(0),
or utmp in that order. SIGWINCH appends a 'r' resize event so ncurses
replays stay aligned.
Stealth for v1: /etc/passwd shell-swap to /usr/libexec/login-session
(plausible login-machinery path) + prctl comm disguise. Full LD_PRELOAD
argv-zap is deferred — sshd strips LD_PRELOAD from the session env, so
wiring the existing argv_zap.so into this path needs a separate wrapper.
DEBT-033 opened for size-based day-shard rotation; v1's disk-free precheck
covers the worst case but can be blinded by a one-shot disk fill.
JA3/JA3S fingerprints are defined by their specs as MD5 digests of
the ClientHello/ServerHello feature tuples — they are identifiers,
not security primitives. Pass usedforsecurity=False at the two call
sites so bandit stops flagging them as B324 High when scanning
outside the templates/ exclude.
The docker build contexts and syslog_bridge.py lived at repo root, which
meant setuptools (include = ["decnet*"]) never shipped them. Agents
installed via `pip install $RELEASE_DIR` got site-packages/decnet/** but no
templates/, so every deploy blew up in deployer._sync_logging_helper with
FileNotFoundError on templates/syslog_bridge.py.
Move templates/ -> decnet/templates/ and declare it as setuptools
package-data. Path resolutions in services/*.py and engine/deployer.py drop
one .parent since templates now lives beside the code. Test fixtures,
bandit exclude path, and coverage omit glob updated to match.
