* fix(auth): close OAuth open-redirect by wiring AllowedRedirectHosts
Bump go-pkgz/auth/v2 to master (v2.1.2-0.20260421203319-686683f19cf7)
which carries the `from` redirect validator from go-pkgz/auth#275.
The library default with a nil AllowedRedirectHosts is permissive
(preserves legacy behavior for existing consumers on a dep bump), so
just bumping the dep leaves remark42 vulnerable — a crafted
/auth/<provider>/login?from=https://evil.example.com/... still issues
the 307 to the attacker host after the user completes legitimate
OAuth. Verified end-to-end against a local dev-auth instance before
and after this commit.
Wire Opts.AllowedRedirectHosts in getAuthenticator to the operator's
existing --allowed-hosts config, stripping the CSP "self" sentinel
which is not a real hostname. RemarkURL's own host is always implicit
per the library contract, so a default single-site deployment gains
the protection with no config change. Multi-host embeds work as soon
as their embedding hosts are added to AllowedHosts (they already need
to be there for CSP frame-ancestors).
Refreshed vendor tree to match the new module version.
* chore(lint): suppress G703 false positives on image Save
CI's newer gosec flags os.MkdirAll/os.WriteFile in FileSystem.Save with
G703 because id flows in from the caller. id is validated at the HTTP
layer (safePictureSegment in rest_public.go) and dst is derived via
f.location — not a real traversal. Targeted //nolint with reason.
* fix(auth): normalise AllowedRedirectHosts entries + add unit test
Address Copilot review on PR #2049. The previous closure passed raw
s.AllowedHosts entries straight to the auth library, but --allowed-hosts
holds CSP frame-ancestors source expressions: scheme-prefixed values
(https://blog.example.com), entries with ports, and wildcards
(*.cdn.example.com) are all valid there but the auth library compares
against u.Hostname() and would silently drop them — breaking legitimate
redirects on multi-host deployments.
Extract getAllowedRedirectHosts that:
* trims whitespace, drops empty / 'self' / "self" / wildcard entries
* prepends https:// if scheme missing then url.Parse to extract Hostname
* logs a warning on parse failure rather than poisoning the allowlist
Wire the closure in getAuthenticator to call the helper.
Test_getAllowedRedirectHosts covers all the edge cases Copilot flagged
(scheme stripping, port handling, self spellings, wildcards, empty,
mixed real-world).
* fix(auth): preserve explicit port in AllowedRedirectHosts + clarify fs_store nolint
Address Copilot follow-up on PR #2049:
* getAllowedRedirectHosts stripped explicit ports via u.Hostname(), which
broadened the allowlist. The auth validator checks both Hostname() and
Host, so an entry like admin.example.com:8443 can and should be kept
host:port — allowing only that port, not any. Emit u.Host when
u.Port() != "", u.Hostname() otherwise. Updated tests.
* fs_store Save nolint rationale said "id validated at HTTP layer", but
Save is reached via image.Service.Save and SaveWithID (cache), neither
of which is HTTP validation. id is actually a server-generated hash in
both paths. Updated the comment.
Go 1.25's testing/synctest package (GA) provides a fake clock bubble
for deterministic goroutine and timer testing. Convert tests that
waited on real-time durations to use synctest, removing most wall-clock
time.Sleep workarounds.
Converted (11 tests, 9 files):
- notify/notify_test.go — all tests, replaced 17 time.Sleep(110ms) with synctest.Wait()
- store/service/service_test.go — VoteSameIPWithDuration, UserReplies, submitImages,
ResubmitStagingImages, deleteImagesOnCommentDelete
- store/image/{image,bolt_store}_test.go — Cleanup, Submit, SubmitDelay
- store/engine/bolt_test.go — FlagListBlocked
- providers/telegram_test.go — DispatchTelegramUpdates
- migrator/backup_test.go — TestBackup_Do
- _example/memory_store/accessor/data_test.go — FlagListBlocked
Simplifications along the way:
- notify/notify_mock.go: dropped the 10ms time.After delay and
ctx.Done select in MockDest — the artificial I/O simulation is
pointless and blocked synctest.Wait from draining the queue
- Removed three dead-code time.Sleep(1s) calls in EditCommentDurationFailed,
EditCommentAdmin, and Info tests: prepopulated comments from 2017
already exceed any EditDuration/ReadOnlyAge under real clock, making
the sleeps meaningless
- UserReplies: replaced the Eventually+Sleep+mutex polling with a
direct time.Sleep under fake clock
Skipped (incompatible with synctest):
- fs_store_test.go: relies on OS file mtime (real wall clock)
- rss_test.go: needs real wall-clock second boundary for pubDate
- admin/rest_private/rest_public tests: httptest network I/O
- cmd/server_test.go: real HTTP server startup polling
Notes on quirks encountered:
- synctest.Wait() does NOT advance fake time, contrary to what one
might expect. It only returns once all other bubble goroutines are
durably blocked. To advance the fake clock, the test goroutine must
itself call time.Sleep
- BoltDB keys the "last" bucket by comment.Timestamp nanosecond string.
Rapid b.Create calls under frozen fake time produce identical keys
and overwrite each other. TestService_UserReplies adds
time.Sleep(time.Nanosecond) between Creates to advance the clock
- Bolt image Cleanup uses strict age > ttl. Under fake time the
age-ttl delta is exactly zero at the boundary, so subtract 1ms from
the passed ttl to stay strictly under
Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: umputun <535880+umputun@users.noreply.github.com>
Address all golangci-lint v2.10.1 (CI's version) findings:
* Add http.MaxBytesReader hard cap to ParseMultipartForm sites in
rest_private.savePictureCtrl (32MB) and api/migrator (256MB) — fixes
G120 by bounding total request body before form parsing.
* Suppress G70x in CLI subcommands cmd/{backup,cleanup,import,remap}.go:
all four issue HTTP requests against operator-supplied RemarkURL/CLI
flags, never user input. Each suppression carries a one-line reason.
* Suppress G122 in image fs_store cleanup walk: staging directory tree
is server-only, no untrusted symlinks land there.
The image proxy got an ssrfSafeTransport in commit aca0cff3 that resolves
DNS first, blocks any IP in private/reserved CIDRs, then dials by IP to
defeat DNS rebinding. The TitleExtractor used to construct comments'
PostTitle from Locator.URL — a user-supplied field — was missed by that
fix and kept using http.DefaultTransport. The hostname allowlist there
checks the parsed URL host but never the IP it resolves to, so a domain
suffix-matching an allowed host (or 127.0.0.1 itself when AllowedHosts
is empty) reaches the metadata service or any other internal endpoint.
The same gosec rule (G704) was excluded globally in .golangci.yml as part
of aca0cff3, so this gap was not caught by the linter either.
Extract the transport into a new safehttp package so it lives in one
place and can be reused, then pass safehttp.Transport() into the
TitleExtractor's http.Client at construction (cmd/server.go). The image
proxy switches to safehttp.Transport() too — same behaviour, no longer
duplicated.
Reproduction in title_test.go uses the production-style client to hit
an httptest.Server (always 127.0.0.1) and asserts the dialer refuses
even though "127.0.0.1" is in the allowed-domains list. A control case
shows the same setup without safehttp.Transport returns the page —
making the original vulnerability explicit.
The store tests stored timestamps with time.Local in their fixtures and
asserted equality against returned values that the engine round-trips
through UTC. assert.Equal compares zone identity, so on UTC machines
(CI, most cloud envs) Local==UTC and the tests passed; on a developer
machine in any other timezone (here BST, UTC+1) TestService_Put,
TestService_List, TestBoltDB_InfoPost, TestBoltDB_InfoList and several
others would fail with same wall-clock numbers but mismatched zones.
Replace time.Local with time.UTC across store/comment_test.go,
store/formatter_test.go, store/service/service_test.go,
store/engine/bolt_test.go, store/engine/engine_test.go. Production code
is untouched.
Apply go fix ./... analysers (Go 1.26) across backend and examples:
- interface{} → any (type alias, no behaviour change)
- for i := 0; i < N; i++ → for range N / for i := range N
- slices.Contains / slices.ContainsFunc replacing manual loops
- strings.SplitSeq replacing strings.Split in range (avoids allocation)
- strings.CutPrefix replacing HasPrefix+TrimPrefix
- min() replacing manual if/else
- fmt.Appendf replacing []byte(fmt.Sprintf(...))
- strings.Builder replacing string += concatenation
- wg.Go(func(){}) replacing wg.Add(1)/go/wg.Done() pattern
- removed redundant ii := i loop variable copies (unnecessary since Go 1.22)
omitempty on struct-typed JSON fields: go fix removed omitempty from
struct-typed fields (time.Time, PostInfo, UserDetailEntry) because
encoding/json's omitempty never applied to struct types — it was always
a no-op. Kept as bare tags (no omitzero replacement) to preserve the
existing serialisation behaviour.
Replace strings.Split(RemoteAddr, ":") with net.SplitHostPort for correct
IPv6 address extraction in vote deduplication and comment IP tracking.
Harden image proxy: add SSRF-safe transport blocking private/reserved IPs
at connection time with DNS rebinding protection, sanitize error messages
to prevent information leakage, add response size limit via io.LimitReader.
Fix shadowed error variables in BlockedUsers, SetTitle, and Delete methods.
Exclude gosec taint analysis false positives at linter config level.
When EditDuration is zero or negative, cleanupTTL becomes zero,
causing time.After(0) to fire immediately in a tight loop.
Block on ctx.Done() instead when edit duration is disabled. Fixes#1991
`format=tree` pagination provides top-level comments with all replies
and returns the last top-level comment as `last_comment` to be used
as `offset` for the next page. If comments and replies overflow
the limit, the one stepping out of the limit will not be returned.
If the first comment and its replies after the given offset overflow
the limit, it will be returned with all the replies.
`format=plain` pagination works by providing all comments and returning
the last comment as `last_comment` to be used as `offset`
for the next page.
MakeTree calculated Info locally for historical reasons,
and the results were consistent with the dataService.Info call
but calculated differently.
That change fixes that, ensuring that Info is requested
in the same manner.
Previously, images were deleted only from comments deleted
before EditDuration expiration. After this change, any deletion
of the comment deletes images if they are not used elsewhere
in comments under the same page.
Previously, only the first one was returned for site-wide requests,
and now all returned information will be correctly aggregated,
and the PostInfo.URL and PostInfo.ReadOnly parameters will be dropped.
Allowed domains consist of `REMARK_URL` second-level domain (or whole IP in case it's IP like `127.0.0.1`) and `ALLOWED_HOSTS`. That is needed to prevent Remark42 from asking arbitrary servers and storing the page title as the comment.PostTitle.
Previous behaviour allowed the caller of the API to create a comment
with an arbitrary URL and learn the title of the page, which might be
accessible to the server Remark42 is installed on but not to the user
outside that network (CWE-918).
Allowed domains consist of `REMARK_URL` second-level domain (or whole IP in case it's IP like `127.0.0.1`) and `ALLOWED_HOSTS`. That is needed to prevent Remark42 from asking arbitrary servers and storing the page title as the comment.PostTitle.
Previous behaviour allowed the caller of the API to create a comment
with an arbitrary URL and learn the title of the page, which might be
accessible to the server Remark42 is installed on but not to the user
outside that network (CWE-918).
Previously, we stripped unsafe HTML tags but left some,
but it's not expected to have a link in a title or username,
so the new behaviour is stripping everything.
Previously, proxied and local images were checked for presence in the
storage before previewing or posting the comment. That logic resulted in
an inability to post with an image when a proxy for images is enabled,
as proxied images are not downloaded to disk before the first time
someone loads them, which could only happen after the user either
previews or posts the message.
After this change, preview and post only checks the local images'
presence and ignore the proxied ones.
1) Current implementation simply removes the last word, without truncating up to limit length.
2) In case if even the first word (magnet link or some base64?) is too long don't add extra space.
(url) is a text inserted by default and never an intended URL.
That additional validation will ensure that users won't post relative
links because they are rarely intended.
I haven't found a linter for these, so I had to catch these manually.
I found #757 to fix one of these, and I thought it would be good
to fix everything at once.
Previously, the cache kept the entry and deletion of the parent comment
after child deletion was not possible for the rest
of cache life (5m) duration. Now it's possible to delete
a parent comment after the deletion of the child comment
by a user or admin.
Resolves#1481
Fixes the following conversion problem for BlockedUser:
```
panic: interface conversion: interface {} is map[string]interface {},
not store.BlockedUser [recovered]
```
Resolves#1475.
Previously it was sanitised using the HTML sanitiser,
but it had proven troublesome and unnecessary.
Remark42 rendered the markdown into proper HTML, but then some pieces
of it (like cited HTML code inside the code block, marked by backticks)
were cut out, which then showed the incorrect markdown to a user when
they were editing the comment.
For example, the comment "`foo<bar>`" became "foo" after sanitising,
and despite the proper render user saw only "foo" when editing
the comment.
After this change, the initial comment markdown is preserved unaltered.
It could contain dangerous HTML with JS, which I assume shouldn't
be a problem as it's never rendered as HTML but instead supposed
to be converted to HTML by the interpreter. In Remark42, it's stored
in a comment.Text field and sanitised and thus safe.
I've left information about the potential danger of rendering
the original markdown as-is without an interpreter in
all relevant places I could find.
Previously we built a Docker image just for the test,
but the introduction of multi-arch build in 9fbf0952
build also meant the push of the image, so it was
restricted only to the master branch.
This change re-introduces the Docker image build
outside the master branch, which is helpful
in pull requests.
We recently had a few frontend PRs which broke
the Docker image build silently, and that change
prevents it from happening.
