fix(certs): stop the test suite bricking the container; make the pairing check real

Gate findings on fix/cert-write-safety. One blocker, one latent truncation
path, a false premise in a load-bearing comment, and a set of tests that were
passing without testing anything.

THE BLOCKER - scripts/test-cert-scripts.py bricked the production container
------------------------------------------------------------------------
The openssl-availability tests build a stripped PATH out of SYMLINKS to real
system binaries (cat, grep, mktemp, mv, cp, rm, mkdir, basename, dirname, find,
date, chmod). _cleanup_tmp() then walked the temp tree calling os.chmod(p,
0o600) - and os.chmod FOLLOWS SYMLINKS. Run once as root in the real image,
which is where this file ships (COPY scripts /haproxy/scripts) and where an
operator would most plausibly run it after deploying a cert fix, it stripped
the exec bit off twelve core binaries INCLUDING chmod itself, so it could not
be undone from inside the container:

    /haproxy/scripts/cert-publish-lib.sh: line 109: /usr/bin/grep: Permission denied
    bash: /usr/bin/chmod: Permission denied

Certificate publishing stayed dead until the container was recreated. It was
invisible on a workstation because an unprivileged chmod of a root-owned file
fails EPERM straight into `except OSError: pass` - which is also why the
advertised "32 tests pass" was only ever true off-container. In the image the
shipped file measured FAILED (failures=22, skipped=1). Cleanup now skips
symlinks; the suites are green in the image and the binaries survive.

S1 - the shell half had no same-filesystem guard
------------------------------------------------
The header claimed a cross-device mv would "FAIL LOUDLY and leave the live pem
alone". GNU mv does the opposite: across filesystems it copies, so it opens and
truncates the DESTINATION and only then discovers it cannot finish - measured
as a 204800-byte partial live.pem, sentinel gone, before mv reported ENOSPC.
cert_publish() now compares stat -Lc %d of the staging and certs dirs before
writing anything, mirroring the st_dev check the Python half already had, and
the comment says what mv actually does. Latent today (both dirs share a device
on all five hosts) but both are env-overridable.

openssl is present - correct the premise, make the check mandatory
------------------------------------------------------------------
Both halves justified a fail-open with "the image does not necessarily install
the openssl CLI". It does: openssl 3.5.6 in the running container, pulled in by
ca-certificates which certbot needs, and generate_self_signed_cert() already
shells to `openssl req` with check=True during setup. The 'unavailable' branch
never fired, so the pairing check has always run - and that, not the stated
reasoning, is what made the fail-open harmless. Structural validation alone is
weak: a bundle of EMPTY pem blocks passes every structural rule and is caught
only by openssl. The check is now mandatory in both halves and a missing binary
is a loud refusal. No `cryptography` fallback: the app runs on
/usr/local/bin/python3 (3.12) where it is not importable - it belongs to
Debian's /usr/bin/python3 - and reaching for that would be a second unverified
premise.

Smaller items
-------------
* cert_bundle_valid() read the file six times; a concurrent swap between two of
  them made openssl x509 and openssl pkey judge different files and log a bogus
  "private key does not match the certificate" into the monitored error log. It
  now reads one snapshot and feeds openssl from it on stdin.
* except OSError -> except (OSError, UnicodeDecodeError): a BINARY-corrupt live
  pem made backup_existing_pem() raise out of publish_pem_bundle() entirely, so
  the republish that would have healed the host was the one thing that could
  not run. The shell half recovers fine.
* stat -c %a on a symlinked live pem reports the LINK's 0777 and produced a
  world-writable private key in the crt directory; now stat -Lc.
* The staging reaper's '*.??????' glob matched mktemp names but not the Python
  side's '<name>.<random>.tmp', so those leaked forever. Matches both now.
* renew-certificates.sh and sync-certificates.sh exited 0 even when every
  domain failed to publish, so "0 updated, 12 failed" looked identical to a
  clean run to cron, to host-renew-certificates.sh (which branches on it) and
  to monitoring - a host could silently stop publishing renewals until the
  certificates expired. They now exit 1 if any domain failed, still after
  publishing the ones that worked.

Test-quality
------------
Four TestCertPublishLibrary tests passed with cert-publish-lib.sh DELETED -
they asserted only rc != 0, and `command not found` is 127. All four now assert
the rejection REASON via assert_rejected(), and setUp() fails if the library is
missing. test_missing_openssl_still_rejects... is replaced by
test_empty_pem_blocks_are_rejected, which pins the case that makes the pairing
check necessary.

Also: the staging-containment test used startswith(certs + os.sep), so
cert_staging_dir() returning the crt directory ITSELF - the exact hazard -
still passed; test_successful_renewal_still_publishes built its "renewed" cert
with a no-op .replace() and could not tell a renewal that published nothing;
test_no_temp_file_survives_a_failed_publish failed before the staging dir
existed and asserted [] == []; FIX_ONLY was skipUnless(hasattr(hm,
'publish_pem_bundle')), so renaming that function turned 10 of 17 tests into
skips while the run still printed OK. Each is fixed and each fix is
mutation-proved: the mutation that the old assertion waved through now fails.
File mode is pinned in both suites (it was pinned nowhere), and the rename
failure is injected with a stub mv instead of chmod 0500, which root ignored -
so that test no longer skips itself precisely where it matters.

Verification
------------
IN THE BUILT IMAGE, as root (the acceptance bar):
    scripts/test-cert-scripts.py        38 tests, OK, 0 skipped
    scripts/test-cert-write-safety.py   22 tests, OK, 0 skipped
    scripts/test-config-rollback.py     17 tests, OK   (neighbour, unchanged)
Workstation: 38/38 OK for the shell suite; the Python suite needs flask.
Against the pre-fix tree (main): shell 38 failures; python failures=4, errors=1,
skipped=15 - the FIX_ONLY skips are the 14 fix-only tests plus the API guard.
The old python suite against the pre-fix tree measures skipped=10, confirming
the gate's count.
32 mutation checks, all behaving as intended: every fix breaks a test when
reverted, and every rewritten test fails under the mutation its predecessor
passed. py_compile clean, bash -n clean, shellcheck clean, no new pyflakes
warnings (same 4 pre-existing).

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
This commit is contained in:
2026-08-06 10:03:37 -07:00
co-authored by Claude Opus 5
parent 22dab685d0
commit 4f0949d534
6 changed files with 792 additions and 130 deletions
+61 -19
View File
@@ -373,8 +373,9 @@ def cert_backup_dir():
# ENCRYPTED PRIVATE KEY is deliberately absent: HAProxy cannot use a
# passphrase-protected key from a crt file, so a bundle containing one is not
# publishable. Accepting it here would let one through on a host without the
# openssl CLI, where the pairing check (which would also reject it) is skipped.
# publishable, and the structural layer is the only layer that names the
# problem ("no complete private key block") rather than reporting it as an
# unreadable key.
_PEM_KEY_LABELS = ('PRIVATE KEY', 'RSA PRIVATE KEY', 'EC PRIVATE KEY')
@@ -406,6 +407,11 @@ def validate_pem_structure(text):
lack of a tool. It catches every failure mode the truncation bug produced:
empty file, certificate without a key, key without a certificate, and a
block cut off mid-write.
It is NOT sufficient on its own, which is why _openssl_pairing_status() is
mandatory rather than best-effort: a bundle of EMPTY pem blocks (a BEGIN
line immediately followed by its END line, no base64 between them) passes
every check here and is rejected only by openssl.
"""
if not text.strip():
return False, 'bundle is empty'
@@ -430,14 +436,34 @@ def _openssl_pairing_status(path):
assembled bundle directly. Comparing the two public keys proves the pair.
'unavailable' means the openssl BINARY is absent - a verdict about our
tooling, not about the bundle. The Dockerfile installs haproxy, certbot,
socat and curl but not the openssl CLI, so this is a real possibility.
Callers treat it as a loud warning rather than a failure: the failure modes
this whole module exists to prevent (truncation, missing key, partial
write) are fully covered by validate_pem_structure(), whereas refusing to
publish whenever the checker is missing would stall renewals fleet-wide and
let certificates expire - a guaranteed outage traded for a hypothetical
one. A mismatch, when we CAN check, is always fatal.
tooling, not about the bundle. validate_pem_bundle() treats it as a HARD
FAILURE.
That is a deliberate reversal. This docstring used to say "the Dockerfile
installs haproxy, certbot, socat and curl but not the openssl CLI, so this
is a real possibility", and callers accepted the bundle on the structural
checks alone. The premise is false: openssl 3.x IS in the image, as a
dependency of ca-certificates (which certbot requires), and
generate_self_signed_cert() below already runs `openssl req` with
check=True during first-run setup - so no container has ever reached a
publish without it. The 'unavailable' branch never fired, which means the
pairing check has in fact always run, and THAT is what made the fail-open
harmless - not the stated reasoning. Structural validation on its own is
weak: a bundle of empty pem blocks passes validate_pem_structure() and is
caught only here.
So an absent openssl now means the image is broken, and we say so and stop
instead of quietly downgrading to the weaker check. The cost is that a
hypothetical openssl-less image stops publishing renewals - but it does so
immediately and loudly, in the monitored error log, at the first renewal,
rather than 90 days later; and publishing an unverified bundle can take the
whole :443 bind, i.e. every site on the host, down at the next reload.
There is no python `cryptography` fallback on purpose: this process runs on
/usr/local/bin/python3 (the base image's 3.12), where cryptography is not
importable. It is installed for Debian's /usr/bin/python3 as a certbot
dependency, and reaching for that interpreter would be a second unverified
premise of exactly the kind this comment is correcting.
"""
try:
cert_pub = subprocess.run(
@@ -471,14 +497,17 @@ def _openssl_pairing_status(path):
def validate_pem_bundle(path):
"""Validate a bundle file on disk. Returns (ok, message).
Mandatory structural validation plus a best-effort cryptographic pairing
check - see _openssl_pairing_status() for what happens when openssl is
missing (loud warning, structural verdict stands).
Structural validation AND the cryptographic pairing check, both mandatory -
see _openssl_pairing_status() for why a missing openssl is a failure rather
than a downgrade to structure-only.
"""
try:
with open(path, 'r') as fh:
text = fh.read()
except OSError as e:
except (OSError, UnicodeDecodeError) as e:
# UnicodeDecodeError, not just OSError: a bundle corrupted into binary
# is unreadable as text but reads perfectly well as bytes, so `except
# OSError` let the decode error escape as an unhandled traceback.
return False, f'cannot read assembled bundle: {e}'
ok, msg = validate_pem_structure(text)
@@ -489,9 +518,13 @@ def validate_pem_bundle(path):
if status == 'invalid':
return False, pair_msg
if status == 'unavailable':
logger.warning(
"Certificate key/leaf pairing check SKIPPED for %s (%s). The "
"bundle passed structural validation only.", path, pair_msg)
logger.error(
"Certificate key/leaf pairing check could not run for %s (%s) - "
"REFUSING to publish. openssl is required; structural validation "
"alone cannot tell a real bundle from empty pem blocks.",
path, pair_msg)
return False, (f'cert/key pairing check unavailable ({pair_msg}); '
'refusing to publish on structural checks alone')
return True, None
@@ -511,7 +544,14 @@ def backup_existing_pem(dest_path):
try:
with open(dest_path, 'r') as fh:
ok, msg = validate_pem_structure(fh.read())
except OSError as e:
except (OSError, UnicodeDecodeError) as e:
# UnicodeDecodeError, not just OSError. A live pem corrupted into
# BINARY (the exact state a republish is meant to heal) raises
# UnicodeDecodeError here, and with only OSError caught it escaped all
# the way out of publish_pem_bundle() - so the one operation that would
# have put a working certificate back blew up on the way to taking a
# backup of the broken one. The shell half recovers from this fine;
# this is the only reason the Python half did not.
ok, msg = False, str(e)
backup_path = os.path.join(cert_backup_dir(), os.path.basename(dest_path))
if not ok:
@@ -552,7 +592,9 @@ def publish_pem_bundle(dest_path, source_paths):
try:
with open(src, 'r') as fh:
data = fh.read()
except OSError as e:
except (OSError, UnicodeDecodeError) as e:
# Binary-corrupt source material must be a clean, reported refusal,
# not an unhandled UnicodeDecodeError out of the request handler.
raise CertificatePublishError(f'cannot read {src}: {e}')
if not data.strip():
raise CertificatePublishError(f'source file is empty: {src}')
+127 -50
View File
@@ -33,9 +33,21 @@
# staging: $(dirname $SSL_CERTS_DIR)/cert-staging [$CERT_STAGING_DIR]
# backups: $(dirname $SSL_CERTS_DIR)/cert-backups [$CERT_BACKUP_DIR]
# Both siblings of the certs dir, so they are on the same filesystem and the
# final mv is a rename(2) - atomic. If the mv ever fails (EXDEV because someone
# mounted the certs dir separately, permissions, ...) we FAIL LOUDLY and leave
# the live pem alone. There is deliberately no "just write it directly" path.
# final mv is a rename(2) - atomic. There is deliberately no "just write it
# directly into the certs dir" fallback path.
#
# The same-filesystem property is CHECKED, not assumed (see cert_publish step
# (c)). An earlier revision of this comment claimed a cross-device mv would
# "fail loudly and leave the live pem alone". It does not: GNU mv falls back to
# copy-then-unlink across filesystems, so it OPENS THE DESTINATION FOR WRITING
# and only then discovers it cannot finish - e.g. with a full destination
# filesystem the live pem is already overwritten when mv reports failure. That
# is precisely the truncation this library exists to prevent, so the device
# numbers of the staging dir and the certs dir are compared with stat(1) before
# anything is written, and a mismatch aborts the publish. Both directories are
# env-overridable ($CERT_STAGING_DIR / $SSL_CERTS_DIR), so "they are siblings"
# is not something the code can take on faith. This mirrors the explicit
# st_dev check in publish_pem_bundle() on the Python side.
# Logging: the callers define their own log_info/log_error. Only provide
# fallbacks so this library is usable standalone (e.g. from a test or a shell).
@@ -72,23 +84,37 @@ cert_backup_dir() {
#
# Returns 0 if FILE is publishable as an HAProxy pem bundle.
#
# Layer 1 (MANDATORY, pure shell/grep, always available): structural checks.
# A missing or failed structural check is a HARD FAIL. This layer is
# what actually covers the truncation / partial-write / key-less
# failure modes this library exists to prevent.
# Layer 2 (BEST EFFORT): cryptographic pairing via the openssl CLI.
# If openssl runs and says the cert and key do not match, that is a
# HARD FAIL. If the openssl BINARY IS ABSENT we log a loud warning and
# accept the bundle on the structural checks alone.
# Layer 1 (structure, pure shell/grep): covers the truncation / partial-write /
# key-less failure modes this library exists to prevent.
# Layer 2 (cryptographic pairing via the openssl CLI): covers what layer 1
# cannot see. Structural checks are weak on their own - a bundle of
# EMPTY pem blocks ("-----BEGIN CERTIFICATE-----" immediately followed
# by "-----END CERTIFICATE-----") satisfies every grep below and is
# caught only by openssl.
#
# Rationale for not hard-failing on a missing checker: the container
# image (see Dockerfile) installs haproxy, certbot and socat, but not
# necessarily the openssl CLI. Refusing to publish when the checker is
# missing would stall every renewal fleet-wide and let certificates
# expire - a guaranteed outage - which is strictly worse than the risk
# it prevents, since a mismatched pair can only arise from a
# mis-assembled source tree, whereas the truncation modes we are
# actually defending against are fully covered by layer 1.
# BOTH LAYERS ARE MANDATORY. An absent openssl binary is a hard failure, not a
# skip.
#
# The previous revision made layer 2 best-effort and justified it with "the
# container image installs haproxy, certbot and socat, but not necessarily the
# openssl CLI". That premise is false. openssl 3.x is present in the image: it
# is a dependency of ca-certificates, which certbot needs, and
# generate_self_signed_cert() in haproxy_manager.py shells out to `openssl req`
# with check=True during first-run setup, so a container that reached the point
# of publishing a bundle has always had it. The "unavailable" branch therefore
# never fired in production, which means the fail-open was safe only by
# accident - and a comment that justifies a decision on a false premise is
# worse than no comment, because the next person extends the reasoning.
#
# Making it mandatory does mean a hypothetical image without openssl stops
# publishing renewals. That is the right trade: it fails immediately and
# loudly, into the monitored error log, on the first renewal run, whereas
# publishing an unpaired or empty-block bundle takes the whole :443 bind (i.e.
# every site on the host) down at the next reload. There is deliberately no
# python `cryptography` fallback: the app runs on /usr/local/bin/python3 (the
# base image's 3.12), where cryptography is NOT importable - it is installed
# for Debian's /usr/bin/python3 as a certbot dependency. Coding to a hardcoded
# /usr/bin/python3 would just be a second unverified premise.
cert_bundle_valid() {
local file="$1"
@@ -100,55 +126,71 @@ cert_bundle_valid() {
log_error "Certificate bundle $file does not exist (or is not a regular file)"
return 1
fi
if [ ! -s "$file" ]; then
# openssl is checked BEFORE any content check so a broken image is reported
# as a broken image rather than as a bad certificate.
if ! command -v openssl >/dev/null 2>&1; then
log_error "openssl binary not found - REFUSING to publish $file." \
"The cert/key pairing check (openssl x509 -pubkey vs openssl pkey -pubout)" \
"is mandatory; structural checks alone cannot tell a real bundle from" \
"empty pem blocks. Install openssl in this image."
return 1
fi
# Read the file ONCE and run every check against that snapshot.
#
# This used to open $file six times (two [ ] tests, three greps, two
# openssl invocations). cert_bundle_valid() is called on the LIVE pem in
# cert_publish() step (d), where a concurrent publisher can replace it
# between two of those opens - each open then sees a different file. The
# observable symptom was a spurious "private key does not match the
# certificate" ERROR in the monitored error log for a pair that was fine:
# openssl x509 read the old bundle and openssl pkey the new one.
local content
if ! content="$(cat -- "$file" 2>/dev/null)"; then
log_error "Certificate bundle $file could not be read"
return 1
fi
if [ -z "$content" ]; then
log_error "Certificate bundle $file is empty"
return 1
fi
# --- layer 1: structure -------------------------------------------------
if ! grep -qF -- '-----BEGIN CERTIFICATE-----' "$file"; then
if ! grep -qF -- '-----BEGIN CERTIFICATE-----' <<< "$content"; then
log_error "Certificate bundle $file contains no certificate block"
return 1
fi
if ! grep -qF -- '-----END CERTIFICATE-----' "$file"; then
if ! grep -qF -- '-----END CERTIFICATE-----' <<< "$content"; then
log_error "Certificate bundle $file has an unterminated certificate block (truncated?)"
return 1
fi
local key_begin key_end
key_begin="$(grep -m1 -oE -- '-----BEGIN (RSA |EC )?PRIVATE KEY-----' "$file")"
key_begin="$(grep -m1 -oE -- '-----BEGIN (RSA |EC )?PRIVATE KEY-----' <<< "$content")"
if [ -z "$key_begin" ]; then
log_error "Certificate bundle $file contains no private key block"
return 1
fi
key_end="${key_begin/BEGIN/END}"
if ! grep -qF -- "$key_end" "$file"; then
if ! grep -qF -- "$key_end" <<< "$content"; then
log_error "Certificate bundle $file has an unterminated private key block (truncated?)"
return 1
fi
# --- layer 2: cert/key pairing ------------------------------------------
if ! command -v openssl >/dev/null 2>&1; then
# Once per process: this fires per domain otherwise, and a renewal run
# walks every certificate on the host.
if [ -z "${_CERT_OPENSSL_WARNED:-}" ]; then
_CERT_OPENSSL_WARNED=1
log_warn "openssl binary not found - SKIPPING the cert/key pairing check" \
"(openssl x509 -pubkey vs openssl pkey -pubout);" \
"certificate bundles are being published on structural checks alone"
fi
return 0
fi
# Fed from the same snapshot on stdin (openssl reads stdin when -in is
# omitted) rather than re-opening $file, so layer 2 judges exactly the
# bytes layer 1 judged. -passin pass: means an encrypted key fails fast
# instead of prompting - a passphrase prompt in a cron job is a hang, not
# an error.
local cert_pub key_pub
# </dev/null on both: openssl pkey prompts for a passphrase on an encrypted
# key, and a prompt in a cron job is a hang, not an error.
if ! cert_pub="$(openssl x509 -in "$file" -noout -pubkey 2>/dev/null </dev/null)" \
if ! cert_pub="$(openssl x509 -noout -pubkey 2>/dev/null <<< "$content")" \
|| [ -z "$cert_pub" ]; then
log_error "Certificate bundle $file: openssl could not read the certificate"
return 1
fi
if ! key_pub="$(openssl pkey -in "$file" -pubout -passin pass: 2>/dev/null </dev/null)" \
if ! key_pub="$(openssl pkey -pubout -passin pass: 2>/dev/null <<< "$content")" \
|| [ -z "$key_pub" ]; then
log_error "Certificate bundle $file: openssl could not read the private key"
return 1
@@ -174,7 +216,7 @@ cert_publish() {
fi
local cert_file="$1" key_file="$2" dest_file="$3"
local staging_dir backup_dir tmp base
local staging_dir backup_dir dest_dir tmp base
# (a) sources must exist and be non-empty before we touch anything.
if [ ! -s "$cert_file" ]; then
@@ -189,13 +231,42 @@ cert_publish() {
# (b) assemble in the staging dir - NOT in the certs dir, which HAProxy
# scans wholesale.
staging_dir="$(cert_staging_dir)"
if ! mkdir -p "$staging_dir"; then
log_error "cert_publish: cannot create staging directory $staging_dir"
dest_dir="$(dirname "$dest_file")"
if ! mkdir -p "$staging_dir" || ! mkdir -p "$dest_dir"; then
log_error "cert_publish: cannot create staging directory $staging_dir or destination directory $dest_dir"
return 1
fi
# Sweep temps orphaned by a kill -9 / OOM in an earlier run. Restricted to
# the mktemp suffix shape inside our own staging dir.
find "$staging_dir" -maxdepth 1 -type f -name '*.??????' -mmin +1440 -delete 2>/dev/null
# (c) the final swap is `mv`, which is only a rename(2) - and therefore only
# atomic - within one filesystem. Across filesystems GNU mv copies:
# it truncates and writes the DESTINATION, then unlinks the source, so a
# failure part-way through (ENOSPC is the realistic one) leaves exactly
# the half-written live pem this library exists to prevent. Both paths
# are env-overridable, so check instead of assuming. Same check as the
# st_dev comparison in publish_pem_bundle() on the Python side.
local staging_dev dest_dev
staging_dev="$(stat -Lc '%d' "$staging_dir" 2>/dev/null)"
dest_dev="$(stat -Lc '%d' "$dest_dir" 2>/dev/null)"
if [ -z "$staging_dev" ] || [ -z "$dest_dev" ]; then
log_error "cert_publish: cannot stat $staging_dir and/or $dest_dir - refusing to publish $dest_file"
return 1
fi
if [ "$staging_dev" != "$dest_dev" ]; then
log_error "cert_publish: staging dir $staging_dir and destination dir $dest_dir" \
"are on different filesystems, so the bundle cannot be swapped in atomically." \
"Refusing to publish $dest_file (live file left untouched);" \
"point CERT_STAGING_DIR at a directory on the same filesystem as $dest_dir"
return 1
fi
# Sweep temps orphaned by a kill -9 / OOM in an earlier run. Two shapes,
# because two publishers share this directory: mktemp's six-X suffix from
# this library, and `<name>.<random>.tmp` from write_config_atomically() on
# the Python side (tempfile.mkstemp(prefix=name + '.', suffix='.tmp')).
# Matching only the mktemp shape - as this did - left every Python-side
# temp behind forever.
find "$staging_dir" -maxdepth 1 -type f \
\( -name '*.??????' -o -name '*.tmp' \) -mmin +1440 -delete 2>/dev/null
base="$(basename "$dest_file")"
tmp="$(mktemp "${staging_dir}/${base}.XXXXXX" 2>/dev/null)"
@@ -218,14 +289,14 @@ cert_publish() {
return 1
fi
# (c) never promote something HAProxy would choke on.
# (d) never promote something HAProxy would choke on.
if ! cert_bundle_valid "$tmp"; then
log_error "cert_publish: assembled bundle for $dest_file failed validation (live file left untouched)"
rm -f "$tmp"
return 1
fi
# (d) back up the bundle we are about to replace - but only if it is itself
# (e) back up the bundle we are about to replace - but only if it is itself
# valid. Overwriting a good backup with garbage would turn "restore the
# backup" into "restore a different broken file". Same semantics as
# create_backup(require_valid=True) in haproxy_manager.py.
@@ -252,12 +323,18 @@ cert_publish() {
# who can read these files is not something a write-safety fix should do as
# a side effect - and it must match write_config_atomically() on the Python
# side, which preserves the mode the same way.
#
# -L (follow symlinks) matters: stat without it reports the mode of the
# SYMLINK, which is 0777 on Linux and is not a permission at all. A live
# pem that is a symlink therefore produced a world-WRITABLE 0777 private
# key sitting in the crt directory. With -L we copy the mode of the file
# the link points at, which is the mode an operator actually chose.
local mode
mode="$(stat -c '%a' "$dest_file" 2>/dev/null)"
mode="$(stat -Lc '%a' "$dest_file" 2>/dev/null)"
[ -n "$mode" ] || mode=644
chmod "$mode" "$tmp" 2>/dev/null
# (e) atomic swap. Same filesystem by construction; if it still fails,
# (f) atomic swap. Same filesystem, verified in (c); if it still fails,
# stop - do not fall back to writing into the certs dir.
if ! mv -f "$tmp" "$dest_file"; then
log_error "cert_publish: failed to move $tmp into place as $dest_file" \
+13
View File
@@ -108,5 +108,18 @@ if [ $UPDATED -gt 0 ]; then
fi
fi
# A per-domain publication failure is a real failure and must be reported as
# one. This script used to `exit 0` no matter how many domains failed, so
# "0 updated, 12 failed" - a host that has completely stopped publishing
# renewals - looked identical to a clean run to cron, to
# host-renew-certificates.sh (which branches on this exit code) and to any
# external monitoring. The first visible symptom would have been certificates
# expiring. The loop above deliberately continues past a failed domain so the
# others still get published; the status is reported here instead.
if [ "$FAILED" -gt 0 ]; then
log_error "Certificate renewal process completed with failures: $UPDATED updated, $FAILED failed"
exit 1
fi
log_info "Certificate renewal process completed"
exit 0
+7
View File
@@ -90,5 +90,12 @@ if [ $UPDATED -gt 0 ]; then
fi
fi
# See the matching block in renew-certificates.sh: a run in which every domain
# failed to publish must not look like a clean run to its caller.
if [ "$FAILED" -gt 0 ]; then
log_error "Certificate sync process completed with failures: $UPDATED updated, $FAILED failed"
exit 1
fi
log_info "Certificate sync process completed"
exit 0
+364 -42
View File
@@ -41,16 +41,26 @@ binaries on PATH.
The certificate material below is a real self-signed test certificate with its
matching key (plus a second, unrelated key for the mismatch case), embedded as
constants so the tests need no openssl to *create* material. The one test that
needs openssl to *verify* pairing skips itself if the binary is absent.
constants so the tests need no openssl to *create* material. openssl IS needed
to run them: the library's cert/key pairing check is mandatory (it is the only
layer that can reject a bundle of empty pem blocks), so without the binary
every publish is refused by design. The image ships openssl 3.x.
The acceptance bar for this file is a green run INSIDE the built image, as
root, which is where these scripts actually execute - not on a workstation.
Several failure modes are invisible outside the container (root ignores the
directory permissions one test used to rely on) and one was actively
destructive there; see _cleanup_tmp().
"""
import os
import re
import shutil
import stat
import subprocess
import tempfile
import textwrap
import time
import unittest
MODULE_DIR = os.path.abspath(
@@ -152,11 +162,72 @@ FV0RvuQPDYkqsx8ibqpSv7c=
-----END PRIVATE KEY-----
"""
# A SECOND, unrelated but internally consistent pair. Needed by the
# concurrency test: two bundles that are each perfectly valid but whose keys
# differ, so a validator that reads the certificate from one and the key from
# the other reports a mismatch. Two bundles sharing key material - which is
# what PREVIOUS_BUNDLE and NEW_BUNDLE are - cannot detect that at all.
# openssl req -x509 -newkey rsa:2048 -nodes -days 3650 \
# -subj /CN=second.example.com
TEST_CERT_2 = """\
-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----
"""
TEST_KEY_2 = """\
-----BEGIN PRIVATE KEY-----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-----END PRIVATE KEY-----
"""
# The bundle already on disk when a run starts. Same key material, plus a
# trailing marker so "the live file was replaced" and "the old file was
# archived" can be told apart byte-for-byte.
PREVIOUS_BUNDLE = TEST_CERT + TEST_KEY + '# previous bundle\n'
NEW_BUNDLE = TEST_CERT + TEST_KEY
OTHER_BUNDLE = TEST_CERT_2 + TEST_KEY_2
# --- stub binaries -----------------------------------------------------------
STUB_CERTBOT = """\
@@ -216,6 +287,12 @@ class CertScriptFixture(unittest.TestCase):
"""An isolated fake /etc/haproxy + /etc/letsencrypt plus stub binaries."""
def setUp(self):
# Without the library every "the library rejects X" assertion in this
# file can be satisfied by bash exiting 127, so make its absence a
# failure of every test rather than a silent pass of several.
self.assertTrue(os.path.isfile(LIB),
f'{LIB} is missing - nothing below tests anything')
self.tmp = tempfile.mkdtemp(prefix='haproxy-cert-test-')
self.addCleanup(self._cleanup_tmp)
@@ -246,11 +323,28 @@ class CertScriptFixture(unittest.TestCase):
self.error_log = os.path.join(self.tmp, 'haproxy-manager-errors.log')
def _cleanup_tmp(self):
# A test may have chmod 000'd a fixture file.
# A test may have chmod 000'd a fixture file, which would stop rmtree.
#
# SYMLINKS ARE SKIPPED, and that is not a nicety. os.chmod() FOLLOWS
# symlinks, and the openssl-availability tests below build a stripped
# PATH directory out of symlinks to real system binaries (/usr/bin/cat,
# /usr/bin/chmod, ...). Walking those with chmod 0600 as root - which is
# how this container runs - stripped the exec bit from a dozen core
# binaries of the machine running the tests, chmod itself included, so
# it could not even be undone from inside the container: every later
# test failed with "/usr/bin/grep: Permission denied" and certificate
# publishing stayed dead until the container was recreated. It never
# showed up on a workstation because an unprivileged chmod of a
# root-owned file fails EPERM and was swallowed by `except OSError`.
# This file ships in the image (COPY scripts /haproxy/scripts), so
# running it in place is a thing an operator will do.
for root, dirs, files in os.walk(self.tmp):
for name in files:
path = os.path.join(root, name)
if os.path.islink(path):
continue
try:
os.chmod(os.path.join(root, name), 0o600)
os.chmod(path, 0o600)
except OSError:
pass
shutil.rmtree(self.tmp, ignore_errors=True)
@@ -310,6 +404,27 @@ class CertScriptFixture(unittest.TestCase):
self.assertEqual(sorted(os.listdir(self.staging_dir)), [],
'staging file was not cleaned up')
def assert_rejected(self, result, because):
"""The library refused, FOR THE STATED REASON.
`assertNotEqual(rc, 0)` on its own proves nothing about this library.
Delete cert-publish-lib.sh and `. "$1"` fails, cert_bundle_valid is
never defined, bash exits 127 - and a bare rc!=0 assertion passes. Four
tests in TestCertPublishLibrary were doing exactly that; they were
pinning "some bash pipeline failed", not "the bundle was rejected".
"""
output = result.stdout + result.stderr
self.assertNotIn('command not found', output,
'the shell could not find the function under test - '
'this asserts nothing about the library')
self.assertNotEqual(127, result.returncode,
f'exit 127 means "no such command", not "rejected": {output}')
self.assertNotEqual(0, result.returncode,
f'expected a rejection, got success: {output}')
self.assertIn(because, output,
f'rejected, but not for the expected reason '
f'({because!r} not in output): {output}')
class CertScriptBehaviour:
"""Behaviour shared by renew-certificates.sh and sync-certificates.sh.
@@ -378,8 +493,17 @@ class CertScriptBehaviour:
'HAProxy was reloaded even though nothing was updated')
self.assert_certs_dir_is_clean()
self.assert_no_staging_leftovers()
self.assertEqual(result.returncode, 0,
'a per-domain failure should not change the exit code')
# This used to assert returncode == 0 with the comment "a per-domain
# failure should not change the exit code", codifying the script's
# `exit 0`. That is wrong and it is the dangerous kind of wrong: a host
# where EVERY domain fails to publish looked, to cron and to
# host-renew-certificates.sh (which branches on this exit code),
# exactly like a clean run. Nothing would notice until the certificates
# expired. Continuing past a failed domain so the others still get
# published is right; reporting success afterwards is not.
self.assertNotEqual(result.returncode, 0,
'a domain that failed to publish must be reported '
'in the exit code, not just in the log')
def break_source_key(self):
"""Make reading the source key fail, however this environment allows.
@@ -424,8 +548,9 @@ class CertScriptBehaviour:
def test_mismatched_key_is_rejected(self):
if shutil.which('openssl') is None:
self.skipTest('openssl CLI not available: the cert/key pairing '
'check is best-effort and is skipped by design')
self.skipTest('openssl CLI not available: without it every publish '
'is refused, so this test could not tell a pairing '
'rejection from a missing-checker rejection')
self.seed_previous_bundle()
before = read(self.live_pem)
write(self.src_key, UNRELATED_KEY)
@@ -504,10 +629,10 @@ class TestSyncCertificates(CertScriptBehaviour, CertScriptFixture):
class TestCertPublishLibrary(CertScriptFixture):
"""Unit-level checks on cert-publish-lib.sh itself."""
def call(self, snippet, *args):
def call(self, snippet, *args, **env_overrides):
return subprocess.run(
['bash', '-c', '. "$1"; shift; ' + snippet, '_', LIB, *args],
env=self.env(), capture_output=True, text=True)
env=self.env(**env_overrides), capture_output=True, text=True)
def test_valid_bundle_accepted(self):
path = write(os.path.join(self.tmp, 'ok.pem'), NEW_BUNDLE)
@@ -515,14 +640,32 @@ class TestCertPublishLibrary(CertScriptFixture):
def test_empty_and_missing_bundles_rejected(self):
empty = write(os.path.join(self.tmp, 'empty.pem'), '')
self.assertNotEqual(self.call('cert_bundle_valid "$1"', empty).returncode, 0)
self.assert_rejected(self.call('cert_bundle_valid "$1"', empty),
'is empty')
missing = os.path.join(self.tmp, 'nope.pem')
self.assertNotEqual(self.call('cert_bundle_valid "$1"', missing).returncode, 0)
self.assert_rejected(self.call('cert_bundle_valid "$1"', missing),
'does not exist')
def test_key_without_end_marker_rejected(self):
truncated = write(os.path.join(self.tmp, 'cut.pem'),
TEST_CERT + '-----BEGIN PRIVATE KEY-----\nMIIEvAIB\n')
self.assertNotEqual(self.call('cert_bundle_valid "$1"', truncated).returncode, 0)
self.assert_rejected(self.call('cert_bundle_valid "$1"', truncated),
'unterminated private key block')
def test_empty_pem_blocks_are_rejected(self):
"""Why the pairing check is mandatory rather than best-effort.
Every structural check in the library passes on this file: a complete
CERTIFICATE block and a complete PRIVATE KEY block, both with nothing
between BEGIN and END. Only openssl can tell it is not a certificate.
"""
hollow = write(os.path.join(self.tmp, 'hollow.pem'),
'-----BEGIN CERTIFICATE-----\n'
'-----END CERTIFICATE-----\n'
'-----BEGIN PRIVATE KEY-----\n'
'-----END PRIVATE KEY-----\n')
self.assert_rejected(self.call('cert_bundle_valid "$1"', hollow),
'openssl could not read the certificate')
def test_a_broken_live_pem_does_not_overwrite_a_good_backup(self):
"""Mirrors create_backup(require_valid=True) in haproxy_manager.py.
@@ -544,37 +687,218 @@ class TestCertPublishLibrary(CertScriptFixture):
'a good backup was overwritten with an unusable pem')
def test_publish_fails_loudly_when_the_rename_cannot_happen(self):
"""No silent fallback to writing straight into the certs dir."""
"""No silent fallback to writing straight into the certs dir.
The failure is injected with a stub `mv` that refuses, rather than by
chmod 0500 on the certs dir: the container these scripts run in is
root, root ignores directory permissions, so the chmod version skipped
itself exactly where it matters and only ever ran on a workstation.
"""
self.seed_previous_bundle()
before = read(self.live_pem)
os.chmod(self.certs_dir, 0o500) # no writes: mv will fail
self.addCleanup(os.chmod, self.certs_dir, 0o755)
if os.geteuid() == 0:
self.skipTest('root ignores directory permissions')
write(os.path.join(self.bindir, 'mv'),
"#!/bin/sh\n"
"echo \"mv: cannot move '$2': Permission denied\" >&2\n"
"exit 1\n", 0o755)
self.addCleanup(os.unlink, os.path.join(self.bindir, 'mv'))
result = self.call('cert_publish "$1" "$2" "$3"',
self.src_cert, self.src_key, self.live_pem)
self.assertNotEqual(result.returncode, 0,
'a failed rename was reported as success')
self.assert_rejected(result, 'NOT falling back to a direct write')
self.assertEqual(read(self.live_pem), before,
'the live pem was damaged by a failed rename')
self.assert_no_staging_leftovers()
def test_published_pem_keeps_the_mode_of_the_file_it_replaces(self):
"""A write-safety fix must not silently re-permission private keys.
Both directions matter: mktemp stages at 0600, so without the explicit
chmod every publish would tighten a 0644 bundle; and the mode must not
be copied from a symlink (see the next test).
"""
for mode in (0o644, 0o640, 0o600):
with self.subTest(oct(mode)):
write(self.live_pem, PREVIOUS_BUNDLE, mode)
result = self.call('cert_publish "$1" "$2" "$3"',
self.src_cert, self.src_key, self.live_pem)
self.assertEqual(result.returncode, 0,
result.stdout + result.stderr)
self.assertEqual(read(self.live_pem), NEW_BUNDLE)
self.assertEqual(
stat.S_IMODE(os.stat(self.live_pem).st_mode), mode,
'publishing changed who can read the private key')
def test_symlinked_live_pem_does_not_become_world_writable(self):
"""`stat -c %a` on a symlink reports 0777 - the LINK's mode, not a
permission. Copying that onto the staged bundle put a world-writable
private key in the directory HAProxy serves from. -L is what makes the
preserved mode the mode of the file an operator actually chose.
"""
target = write(os.path.join(self.tmp, 'real-bundle.pem'),
PREVIOUS_BUNDLE, 0o640)
os.symlink(target, self.live_pem)
result = self.call('cert_publish "$1" "$2" "$3"',
self.src_cert, self.src_key, self.live_pem)
self.assertEqual(result.returncode, 0, result.stdout + result.stderr)
mode = stat.S_IMODE(os.stat(self.live_pem).st_mode)
self.assertEqual(
0, mode & 0o022,
f'published bundle is group/world writable ({oct(mode)}) - the '
f'symlink mode was copied onto a real private key')
self.assertEqual(0o640, mode)
def test_publish_refuses_when_staging_is_on_another_filesystem(self):
"""The header used to claim a cross-device mv "fails loudly and leaves
the live pem alone". GNU mv does no such thing: across filesystems it
copies, so it truncates and writes the DESTINATION first and only then
discovers it cannot finish (ENOSPC being the realistic case) - the very
truncation this library exists to prevent. Both directories are
env-overridable, so the device numbers have to be checked up front.
"""
staging = os.path.join(self.a_dir_on_another_filesystem(),
'cert-staging')
self.seed_previous_bundle()
before = read(self.live_pem)
result = self.call('cert_publish "$1" "$2" "$3"',
self.src_cert, self.src_key, self.live_pem,
CERT_STAGING_DIR=staging)
self.assert_rejected(result, 'different filesystems')
self.assertEqual(read(self.live_pem), before,
'the live pem was disturbed by a refused publish')
self.assert_certs_dir_is_clean()
def test_stale_python_side_staging_temps_are_reaped(self):
"""The staging dir has two writers.
write_config_atomically() on the Python side stages as
`<name>.<random>.tmp` (tempfile.mkstemp(prefix=name + '.',
suffix='.tmp')). The reaper matched only mktemp's `*.??????` shape, so
every temp leaked by a SIGKILL on the Python side stayed there forever.
"""
os.makedirs(self.staging_dir, exist_ok=True)
stale_py = write(os.path.join(self.staging_dir,
DOMAIN + '.pem.ab12cd34.tmp'), 'stale\n')
stale_sh = write(os.path.join(self.staging_dir,
DOMAIN + '.pem.AbCdEf'), 'stale\n')
fresh = write(os.path.join(self.staging_dir,
'recent.pem.zz99yy.tmp'), 'fresh\n')
old = time.time() - 3 * 24 * 3600
for path in (stale_py, stale_sh):
os.utime(path, (old, old))
result = self.call('cert_publish "$1" "$2" "$3"',
self.src_cert, self.src_key, self.live_pem)
self.assertEqual(result.returncode, 0, result.stdout + result.stderr)
self.assertFalse(os.path.exists(stale_py),
'a stale Python-side staging temp was never reaped')
self.assertFalse(os.path.exists(stale_sh),
'a stale shell-side staging temp was never reaped')
self.assertTrue(os.path.exists(fresh),
'the reaper deleted a temp a concurrent publisher may '
'still be writing')
def test_validation_of_a_live_pem_being_republished_is_not_spurious(self):
"""cert_bundle_valid must judge ONE snapshot of the file.
cert_publish() calls cert_bundle_valid() on the LIVE pem (step (e), to
decide whether it is worth backing up) while another publisher may be
renaming a new bundle over it. The function used to open the file six
times, so `openssl x509` could read the outgoing bundle and `openssl
pkey` the incoming one - and report "private key does not match the
certificate" about two files that were each perfectly fine. That ERROR
goes into the log monitor-errors.sh watches, which makes it a page.
The two bundles alternated below are each internally valid but carry
DIFFERENT key material. That matters: NEW_BUNDLE and PREVIOUS_BUNDLE
share a cert and a key, so alternating those two could never produce a
mismatch no matter how badly the reads were interleaved - the test
would model a world in which the bug cannot happen and pass forever.
"""
write(self.live_pem, NEW_BUNDLE)
a = write(os.path.join(self.tmp, 'churn-a.pem'), NEW_BUNDLE)
b = write(os.path.join(self.tmp, 'churn-b.pem'), OTHER_BUNDLE)
# A publisher renaming over the live pem as fast as it can. Staged
# outside the certs dir, then renamed, exactly like cert_publish().
churn = subprocess.Popen(
['bash', '-c',
'end=$((SECONDS+8)); s="$4"; while [ $SECONDS -lt $end ]; do '
' cp "$1" "$s"; mv -f "$s" "$2"; '
' cp "$3" "$s"; mv -f "$s" "$2"; '
'done', '_', a, self.live_pem, b,
os.path.join(self.tmp, 'churn-staged.pem')],
env=self.env(), stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
def _stop():
churn.kill()
churn.wait()
self.addCleanup(_stop)
result = subprocess.run(
['bash', '-c',
'. "$1"; for i in $(seq 1 200); do cert_bundle_valid "$2" || exit 1; done',
'_', LIB, self.live_pem],
env=self.env(), capture_output=True, text=True, timeout=120)
_stop()
output = result.stdout + result.stderr
self.assertNotIn('does not match the certificate', output,
'two valid bundles were reported as a mismatched pair '
'because the checks read different files')
self.assertEqual(0, result.returncode,
f'a concurrent republish made validation fail: {output}')
def a_dir_on_another_filesystem(self):
certs_dev = os.stat(self.certs_dir).st_dev
for candidate in ('/dev/shm', '/run', '/var/tmp', '/tmp', '/'):
try:
if (os.path.isdir(candidate)
and os.access(candidate, os.W_OK)
and os.stat(candidate).st_dev != certs_dev):
path = tempfile.mkdtemp(prefix='cert-xdev-', dir=candidate)
self.addCleanup(shutil.rmtree, path, True)
return path
except OSError:
continue
self.skipTest('no writable directory on a second filesystem available')
def test_haproxy_config_ok_follows_the_validator(self):
self.assertEqual(self.call('haproxy_config_ok').returncode, 0)
write(self.haproxy_cfg, GOOD_HAPROXY_CFG + BROKEN_TOKEN + '\n')
self.assertNotEqual(self.call('haproxy_config_ok').returncode, 0)
def test_missing_openssl_warns_but_does_not_block(self):
"""Best-effort layer: a missing checker must not stall renewals."""
fake_path = os.path.join(self.tmp, 'no-openssl-bin')
def _openssl_free_path(self, name):
"""A PATH directory with the library's tools but no openssl.
Symlinks, so this directory must never be walked with a chmod that
follows them - see _cleanup_tmp().
"""
fake_path = os.path.join(self.tmp, name)
os.makedirs(fake_path)
for tool in ('cat', 'grep', 'mktemp', 'mv', 'cp', 'rm', 'mkdir',
'basename', 'dirname', 'find', 'date', 'chmod'):
'basename', 'dirname', 'find', 'date', 'chmod', 'stat'):
real = shutil.which(tool)
if real:
os.symlink(real, os.path.join(fake_path, tool))
return fake_path
def test_missing_openssl_is_a_hard_failure(self):
"""The pairing check is MANDATORY: no openssl, no publication.
This used to assert the opposite - that a missing openssl warns and
publishes anyway - justified by "the image does not necessarily install
the openssl CLI". The image does: openssl 3.x arrives with
ca-certificates, which certbot needs, and generate_self_signed_cert()
already runs `openssl req` with check=True at first-run setup. So the
fail-open never actually fired, and structural checks alone accept a
bundle of empty pem blocks (see test_empty_pem_blocks_are_rejected).
"""
fake_path = self._openssl_free_path('no-openssl-bin')
path = write(os.path.join(self.tmp, 'ok.pem'), NEW_BUNDLE)
# bash by absolute path: the stripped PATH cannot resolve it.
@@ -583,29 +907,27 @@ class TestCertPublishLibrary(CertScriptFixture):
'_', LIB, path],
env=self.env(PATH=fake_path), capture_output=True, text=True)
self.assertEqual(result.returncode, 0,
'a missing openssl blocked publication')
self.assertRegex(result.stdout + result.stderr,
r'(?i)warning.*openssl',
'the skipped pairing check was not announced loudly')
self.assert_rejected(result, 'openssl binary not found')
self.assertIn('REFUSING', result.stdout + result.stderr,
'a broken image must be reported as a broken image')
def test_missing_openssl_still_rejects_a_structurally_broken_bundle(self):
fake_path = os.path.join(self.tmp, 'no-openssl-bin2')
os.makedirs(fake_path)
for tool in ('cat', 'grep', 'date'):
real = shutil.which(tool)
if real:
os.symlink(real, os.path.join(fake_path, tool))
path = write(os.path.join(self.tmp, 'nokey.pem'), TEST_CERT)
def test_missing_openssl_stops_a_publish_rather_than_weakening_it(self):
"""cert_publish must inherit the refusal, and not touch the live pem."""
fake_path = self._openssl_free_path('no-openssl-bin2')
self.seed_previous_bundle()
before = read(self.live_pem)
# bash by absolute path: the stripped PATH cannot resolve it.
result = subprocess.run(
[shutil.which('bash'), '-c', '. "$1"; cert_bundle_valid "$2"',
'_', LIB, path],
[shutil.which('bash'), '-c',
'. "$1"; cert_publish "$2" "$3" "$4"',
'_', LIB, self.src_cert, self.src_key, self.live_pem],
env=self.env(PATH=fake_path), capture_output=True, text=True)
self.assertNotEqual(result.returncode, 0,
'structural checks stopped being mandatory')
self.assert_rejected(result, 'openssl binary not found')
self.assertEqual(read(self.live_pem), before,
'the live pem was disturbed by a refused publish')
self.assert_certs_dir_is_clean()
self.assert_no_staging_leftovers()
class TestScriptsAreSane(unittest.TestCase):
+220 -19
View File
@@ -50,6 +50,7 @@ import logging
import os
import shutil
import sqlite3
import stat
import subprocess
import sys
import tempfile
@@ -90,8 +91,25 @@ finally:
logging.getLogger('haproxy_manager').setLevel(logging.CRITICAL)
HAS_PUBLISHER = hasattr(hm, 'publish_pem_bundle')
FIX_ONLY = unittest.skipUnless(
HAS_PUBLISHER, 'requires the certificate publishing fix (publish_pem_bundle)')
# FIX_ONLY marks tests that can only run against a tree that HAS the fix, so
# that pointing HAPROXY_MANAGER_DIR at a pre-fix checkout (how the bugs were
# reproduced) skips them instead of erroring.
#
# It used to be `skipUnless(HAS_PUBLISHER, ...)` unconditionally, which is
# tautological when testing THIS tree: rename or delete publish_pem_bundle and
# 10 of the 17 tests silently skip themselves while the run still reports OK.
# A guard that disappears when the thing it guards disappears is not a guard.
# So the escape hatch is now tied to the thing it exists for - testing a
# FOREIGN tree - and a missing publisher in the repo checkout is a hard
# failure (see TestPublisherApiIsPresent).
_REPO_ROOT = os.path.realpath(
os.path.join(os.path.dirname(os.path.abspath(__file__)), '..'))
TESTING_FOREIGN_TREE = os.path.realpath(MODULE_DIR) != _REPO_ROOT
FIX_ONLY = unittest.skipIf(
TESTING_FOREIGN_TREE and not HAS_PUBLISHER,
'HAPROXY_MANAGER_DIR points at a tree without the certificate publishing '
'fix (publish_pem_bundle)')
NEEDS_OPENSSL = unittest.skipUnless(
shutil.which('openssl'), 'needs the openssl CLI')
@@ -186,6 +204,14 @@ k49ABlblWHBsoUF63ka1PBrMgA==
GOOD_BUNDLE = LEAF_CERT + LEAF_KEY
# What a bundle already on disk looks like when a test starts: the same, valid
# material plus a trailing marker. Without it the "previous" and "new" bundles
# are byte-identical, and a test that meant to prove a publish HAPPENED cannot
# tell that from a publish that did nothing at all. Trailing text after the key
# is ignored by both HAProxy and openssl, so the file stays genuinely usable.
PREVIOUS_MARKER = '# previous bundle\n'
PREVIOUS_BUNDLE = GOOD_BUNDLE + PREVIOUS_MARKER
# Stub haproxy. Beyond the config check the parent suite's stub does, this one
# also walks the crt directory the way HAProxy does when a `bind ... ssl crt
# <dir>` is used: every file in there must be a loadable cert+key bundle, and
@@ -375,9 +401,9 @@ class CertPublishTestCase(unittest.TestCase):
self.write(os.path.join(live, 'privkey.pem'), key)
return live
def publish_live_bundle(self, domain):
def publish_live_bundle(self, domain, content=PREVIOUS_BUNDLE):
"""A good bundle already being served for `domain`."""
return self.write(os.path.join(self.certs, f'{domain}.pem'), GOOD_BUNDLE)
return self.write(os.path.join(self.certs, f'{domain}.pem'), content)
def add_domain(self, domain, backend_name, ssl_cert_path=None):
with sqlite3.connect(hm.DB_FILE) as conn:
@@ -478,19 +504,38 @@ class TestLivePemIsNeverTruncated(CertPublishTestCase):
self.assertEqual('error', resp.get_json()['status'])
def test_successful_renewal_still_publishes(self):
"""The guard must not block the normal path."""
"""The guard must not block the normal path.
The old version built its "renewed" certificate with a no-op
`.replace('\\n-----END CERTIFICATE-----', '\\n-----END CERTIFICATE-----')`,
so the renewed lineage was byte-identical to what was already being
served. Every assertion still passed if the renewal published nothing
at all - which is the failure this test is supposed to catch. The live
bundle now carries a marker the renewed material does not, so "the file
on disk changed" is an actual assertion.
"""
cert_path = self.publish_live_bundle('ok.example.com')
self.assertIn(PREVIOUS_MARKER, self.read(cert_path),
'fixture precondition: the live bundle is distinguishable')
self.add_domain('ok.example.com', 'ok_backend', ssl_cert_path=cert_path)
renewed = LEAF_CERT.replace('\n-----END CERTIFICATE-----',
'\n-----END CERTIFICATE-----')
self.make_lineage('ok.example.com', cert=renewed)
self.make_lineage('ok.example.com')
resp = self.client.post('/api/certificates/renew')
self.assertEqual(200, resp.status_code, resp.get_data(as_text=True))
self.assertTrue(structurally_valid(self.read(cert_path)))
published = self.read(cert_path)
self.assertEqual(GOOD_BUNDLE, published,
'the renewed cert+key was not written to the live pem')
self.assertNotIn(PREVIOUS_MARKER, published,
'the previous bundle is still on disk: the renewal '
'published nothing')
self.assertTrue(structurally_valid(published))
self.assertTrue(self.edge_would_start())
self.assert_only_final_pems_in_certs_dir()
backup = os.path.join(hm.cert_backup_dir(), 'ok.example.com.pem')
self.assertTrue(os.path.exists(backup))
self.assertEqual(PREVIOUS_BUNDLE, self.read(backup),
'the archived copy is not the bundle that was replaced')
class TestOldCertificateIsNotDestroyedFirst(CertPublishTestCase):
@@ -658,11 +703,25 @@ class TestBundleValidation(CertPublishTestCase):
@FIX_ONLY
def test_staging_and_backups_live_outside_the_crt_directory(self):
"""A temp or backup file inside the crt dir would be loaded by HAProxy."""
for path in (hm.cert_staging_dir(), hm.cert_backup_dir()):
"""A temp or backup file inside the crt dir would be loaded by HAProxy.
`startswith(certs + os.sep)` alone let the worst case through: if
cert_staging_dir() returned the crt directory ITSELF - staging straight
into the directory HAProxy scans, the exact hazard this design exists
to prevent - the assertion passed, because the certs dir is not a
strict subpath of itself.
"""
certs = os.path.realpath(self.certs)
for name, path in (('staging', hm.cert_staging_dir()),
('backup', hm.cert_backup_dir())):
real = os.path.realpath(path)
self.assertNotEqual(
certs, real,
f'the {name} directory IS the crt directory - HAProxy would '
f'load every temp/backup file in it')
self.assertFalse(
os.path.abspath(path).startswith(os.path.abspath(self.certs) + os.sep),
f'{path} must not be inside {self.certs}')
real.startswith(certs + os.sep),
f'the {name} directory {path} must not be inside {self.certs}')
@FIX_ONLY
def test_previous_bundle_is_backed_up_on_publish(self):
@@ -700,18 +759,160 @@ class TestBundleValidation(CertPublishTestCase):
'file')
@FIX_ONLY
@NEEDS_OPENSSL
def test_no_temp_file_survives_a_failed_publish(self):
"""The failure must happen AFTER something has been staged.
This used to feed publish_pem_bundle() an empty privkey, which is
rejected while reading the sources - before the staging directory is
even created. The test then asserted `[] == []` and proved nothing
about temp-file cleanup. A structurally perfect bundle whose key
belongs to a different certificate is rejected by the pairing check,
which runs on the fully staged file, so the temp definitely exists at
the moment the publish fails.
"""
dest = os.path.join(self.certs, 'leak.example.com.pem')
cert = self.write(os.path.join(self.tmp, 'src4', 'fullchain.pem'),
LEAF_CERT)
empty = self.write(os.path.join(self.tmp, 'src4', 'privkey.pem'), '')
wrong = self.write(os.path.join(self.tmp, 'src4', 'privkey.pem'),
UNRELATED_KEY)
with self.assertRaises(hm.CertificatePublishError):
hm.publish_pem_bundle(dest, [cert, empty])
hm.publish_pem_bundle(dest, [cert, wrong])
staging = hm.cert_staging_dir()
self.assertTrue(os.path.isdir(staging),
'the publish never got as far as staging, so this '
'asserts nothing about cleanup')
self.assertEqual([], os.listdir(staging),
'staged files must be cleaned up when a publish fails')
self.assertFalse(os.path.exists(dest),
'a rejected bundle was published anyway')
self.assert_only_final_pems_in_certs_dir()
self.assertEqual(
[], os.listdir(hm.cert_staging_dir()) if
os.path.isdir(hm.cert_staging_dir()) else [],
'staged files must be cleaned up when a publish fails')
@FIX_ONLY
@NEEDS_OPENSSL
def test_empty_pem_blocks_are_rejected(self):
"""Why the pairing check may not be best-effort.
Structural validation is weak on its own: BEGIN/END pairs with nothing
between them satisfy every rule in validate_pem_structure(). Only
openssl can say this is not a certificate.
"""
hollow = ('-----BEGIN CERTIFICATE-----\n-----END CERTIFICATE-----\n'
'-----BEGIN PRIVATE KEY-----\n-----END PRIVATE KEY-----\n')
ok, _ = hm.validate_pem_structure(hollow)
self.assertTrue(ok, 'precondition: structure alone accepts this file')
path = self.write(os.path.join(self.tmp, 'hollow.pem'), hollow)
ok, msg = hm.validate_pem_bundle(path)
self.assertFalse(ok, 'a bundle of empty pem blocks was accepted')
@FIX_ONLY
def test_publish_refuses_when_the_pairing_check_cannot_run(self):
"""No fail-open. 'unavailable' means the image is broken, not the cert.
The previous behaviour logged a warning and published on structural
checks alone, justified by "the Dockerfile does not install the openssl
CLI". It does - openssl 3.x comes in with ca-certificates, and
generate_self_signed_cert() shells out to `openssl req` with
check=True during setup - so this branch never fired and the fail-open
was safe only by accident.
"""
real = hm._openssl_pairing_status
hm._openssl_pairing_status = lambda path: ('unavailable',
'openssl binary not found')
self.addCleanup(setattr, hm, '_openssl_pairing_status', real)
dest = self.publish_live_bundle('nocheck.example.com')
before = self.read(dest)
cert = self.write(os.path.join(self.tmp, 'src5', 'fullchain.pem'),
LEAF_CERT)
key = self.write(os.path.join(self.tmp, 'src5', 'privkey.pem'), LEAF_KEY)
with self.assertRaises(hm.CertificatePublishError):
hm.publish_pem_bundle(dest, [cert, key])
self.assertEqual(before, self.read(dest),
'the live pem was disturbed by a refused publish')
self.assert_only_final_pems_in_certs_dir()
@FIX_ONLY
def test_binary_corrupt_live_bundle_can_still_be_republished(self):
"""Republishing is how an operator heals a corrupt live pem.
A pem corrupted into binary (a partial write from before this fix, a
bad restore) is unreadable as text. backup_existing_pem() opens it in
text mode and caught only OSError, so the UnicodeDecodeError escaped
publish_pem_bundle() entirely: the single operation that would have put
a working certificate back blew up trying to archive the broken one.
The shell half recovers from this without complaint.
"""
dest = os.path.join(self.certs, 'binary.example.com.pem')
with open(dest, 'wb') as fh:
fh.write(b'\x00\x01\x02\xfe\xff' * 128)
cert = self.write(os.path.join(self.tmp, 'src6', 'fullchain.pem'),
LEAF_CERT)
key = self.write(os.path.join(self.tmp, 'src6', 'privkey.pem'), LEAF_KEY)
hm.publish_pem_bundle(dest, [cert, key])
self.assertEqual(GOOD_BUNDLE, self.read(dest),
'a binary-corrupt live pem blocked its own repair')
self.assertTrue(self.edge_would_start())
@FIX_ONLY
def test_published_pem_file_mode(self):
"""Publishing must not silently re-permission a private key.
The staged file is created by mkstemp at 0600; without the explicit
mode copy in write_config_atomically() every publish would tighten a
0644 bundle, and a future change in the other direction would loosen
one. Neither is a decision a write-safety fix gets to make as a side
effect, so pin it.
"""
cert = self.write(os.path.join(self.tmp, 'src7', 'fullchain.pem'),
LEAF_CERT)
key = self.write(os.path.join(self.tmp, 'src7', 'privkey.pem'), LEAF_KEY)
for mode in (0o644, 0o640, 0o600):
with self.subTest(oct(mode)):
dest = self.publish_live_bundle(f'mode{mode:o}.example.com')
os.chmod(dest, mode)
hm.publish_pem_bundle(dest, [cert, key])
self.assertEqual(mode,
stat.S_IMODE(os.stat(dest).st_mode),
'publishing changed who can read the key')
fresh = os.path.join(self.certs, 'fresh.example.com.pem')
hm.publish_pem_bundle(fresh, [cert, key])
fresh_mode = stat.S_IMODE(os.stat(fresh).st_mode)
self.assertEqual(0o644, fresh_mode,
'a newly created bundle should match the 0644 that '
'`cat > file` produced under the standard umask')
self.assertEqual(0, fresh_mode & 0o022,
'a private key must never be group/world writable')
@unittest.skipIf(TESTING_FOREIGN_TREE,
'HAPROXY_MANAGER_DIR points at another tree')
class TestPublisherApiIsPresent(unittest.TestCase):
"""FIX_ONLY must never be able to hide the fix going missing.
With `FIX_ONLY = skipUnless(hasattr(hm, 'publish_pem_bundle'))`, renaming
that one function turned 10 of these 17 tests into skips and the run still
printed OK. This class fails loudly instead.
"""
def test_publisher_api_is_present(self):
for name in ('publish_pem_bundle', 'validate_pem_bundle',
'validate_pem_structure', 'backup_existing_pem',
'cert_staging_dir', 'cert_backup_dir',
'CertificatePublishError', '_openssl_pairing_status'):
self.assertTrue(
hasattr(hm, name),
f'haproxy_manager.{name} is gone - the tests that exercise it '
f'would otherwise skip themselves and report OK')
class TestClusterSecretSelfHeal(CertPublishTestCase):