MaxBodySize logged r.URL.Path untruncated at WARN, and routes.go
registers it ahead of RequireAuth, so an unauthenticated
POST /source/<8 KB>/edit with an oversize declared Content-Length wrote
attacker-chosen text of attacker-chosen length into the operator's log,
for the cost of a request with no body. The 2,560-byte per-line budget
from #146 did not reach it: that budget lives in the access log's field
capping and this is a separate slog call.
The capping mechanism moves out of internal/middleware into
internal/logfield so there is one budget and one implementation rather
than a second ad-hoc truncation. Truncate and EncodedBytes are
unchanged; the access log now spends logfield.MaxBytes where it spent
maxLogFieldBytes.
The sweep the issue asked for found five more call sites of the same
shape, all reachable unauthenticated, all now capped: the CSRF 403
(also registered ahead of RequireAuth), the rate limiters' 429 (the
per-entrypoint receiver limiter is unauthenticated), RequireAuth's own
DEBUG line, the unknown-entrypoint DEBUG line on the receiver, and the
failed-login DEBUG lines. DEBUG being off by default is not a bound: an
operator turning it on to diagnose a flood must not thereby hand the
flood an unbounded write. Every other slog call in the tree was read
and judged; the PR body lists all of them, including the ones left
alone and why.
MaxBodySize stays ahead of RequireAuth. An oversize body should be
refused before the request buys a cookie decrypt and a session load,
and rejecting first is what keeps an unauthenticated flood from
choosing how much session work the process does. The ordering and what
it costs are now written at the registration, on maxFormBodySize.
MaxAccessLogLineBytes is restated as the ceiling on every slog line
carrying text an UNAUTHENTICATED client supplies, not just the access
log's: each of these lines carries strictly fewer client-supplied
fields than the access log does, so none can be wider. That is asserted
per line under both handlers rather than argued. The claim is qualified
rather than universal because three kinds of writer are outside it, and
the README and the constant now name all three: lines carrying an
authenticated operator's own input, which are not truncated at all (the
webhook name on "webhook created" reaches 600 KB on one line from a
100 KB form field, measured; the SSRF-rejection url and the target_name
lines are the same shape) and are left uncapped deliberately, since
truncating the operator's own configuration echoed back costs
debuggability against no adversary; the log delivery target, which
exists to emit the whole event; and GORM's default logger, which prints
the interpolated SQL to stdout on a record-not-found and is unbounded
on the receiver and login lookups. That last one is a real defect this
audit turned up and is filed separately as #178, not fixed here.
Tests drive 8 KB of client-chosen text at all six sites, through both
handlers internal/logger can install and through each character they
escape — including a bare C0 control, which costs six bytes on the line
against the one it cost to send and is the case a raw-byte budget
breaks on first. Each holds the encoded line to the ceiling, holds the
whole flood's output to what that ceiling allows, and asserts the
markers at the far end of the input are absent, so a value that merely
happened to be short cannot pass. The two login lines past the username
lookup, capped for uniformity rather than need, are pinned too.
internal/logfield gains a test that measures the per-rune charge
against what the handlers really emit over roughly 3,000 code points on
each, so an undercharged rune fails a test instead of quietly
falsifying the ceiling.
Verified by mutation: reverting the MaxBodySize cap alone fails 28
subtests with a 16,583-byte line against the 2,560 ceiling; reverting
the other five fails 70; uncapping the two login lines past the lookup
fails 2; budgeting raw bytes instead of encoded ones fails 23 across
three packages.
In the shipped default, any stranger denied the operator the only
administrative path at 5 requests per minute: TRUSTED_PROXIES is empty,
the README requires a reverse proxy, so every login POST shared one
bucket keyed on the proxy.
Credentials are now verified first and only a FAILED attempt spends
budget, so a correct password is never throttled. Failures are counted
per (client bucket, submitted username), bounded. Concurrent Argon2id
verifications are capped at two, and the queue for them at 16 — because
verifying first lets an attacker force a 64 MB hash per request, and
bounding the wait alone bounds nothing.
The issue's own recommendation was insufficient and is rejected here:
keying by username stops an attacker locking out a DIFFERENT account,
but this is a single-admin product with a predictable bootstrap
username, so flooding the operator's own name still locks them out.
This is speculative — it implements a corrected recommendation ahead of
the owner's ruling so the decision can be made by merging or reverting.
Three things are disclosed rather than glossed: online guessing rises
from 5/min to roughly 27/s, because the 429 is a label on the response
and not a gate in front of the hash; the residual exposure is a loss of
login AVAILABILITY, not latency, and a determined flood still denies
login while it runs, at ~400x the cost and clearing the moment it
stops; and the endpoint should be provisioned for ~400 MB resident, not
the 203 MB of live commitment it itemises.
Independently reviewed four times. Reviewers disproved the suspected
FIFO starvation by measurement, then caught two successive memory
bounds the code did not have — the second by parking waiters and
reading the heap rather than checking the arithmetic.
Rate-limit keys were per-address, i.e. per /128 for IPv6. A routed /64
is the normal residential and mobile allocation, so a client rotated
source addresses inside its own prefix and minted a fresh bucket per
request — evading every limiter at the network layer, with no spoofing
and nothing to detect. #88 closed the header half of this control; this
is the network half.
IPv6 now keys on the /64, IPv4 on the full address, via stdlib
net/netip. IPv4-mapped form is unmapped rather than masked, so clients
behind a mapping proxy do not collapse into one bucket.
Independently reviewed twice. The first round found the trusted-proxy
forwarded path — the one carrying production traffic — had no coverage
at all, so a silent revert there was undetectable; that is now pinned.
The reviewer confirmed both branches are independently mutation-tested:
reverting either the direct-peer return or the forwarded return alone
fails only that branch's tests. The 18-site test-constant refactor was
verified byte-identical against next, with no pre-existing assertion
changed.
Known remaining coverage gap, judged not a defect: the fallback when the
peer is trusted but the forwarded address does not parse has no test.
Only operator-controlled addresses inside TRUSTED_PROXIES reach it, they
already share the proxy's single bucket, and masking there can only
merge operator proxies — fail-closed, nothing attacker-controlled.
check / check (push) Superseded by a newer commit; never tested
The receiver limiter keyed on the request path, and /webhook/{uuid} matches any single segment, so a client minted a fresh bucket per invented path and had unlimited aggregate rate against the only unauthenticated endpoint. An outer limiter keyed on the client address alone now bounds that, chained in front of the unchanged per-entrypoint limiter. Its rejections log at DEBUG without the path, and the README states what each limit does and does not bound.
check / check (push) Superseded by a newer commit; never tested
forwardedClientAddr now walks the header values in reverse with strings.LastIndexByte instead of joining and splitting, so allocation is bounded by the 64-hop cap rather than by header length: 1.6 MB per call becomes 16 bytes for a 1 MB chain. Semantics are unchanged, verified by differential testing against the previous implementation.
The walk now keeps only the rightmost 64 hops, so an attacker-supplied chain cannot burn unbounded CPU in the rate-limit key function. Running off the end of the truncated slice falls back to the peer address, the same fail-closed direction the rest of the function takes. Also corrects the unparseable-RemoteAddr comment, which overclaimed about Unix-socket peers.
All three rate limiters (receiver, login, password change) now key on the connection's own address unless the direct peer is inside the new TRUSTED_PROXIES CIDR list, in which case X-Forwarded-For is walked right to left for the first non-proxy hop. Default is the empty list, which trusts nothing. A set-but-unparseable value aborts startup.
The receiver was the one unauthenticated, internet-facing endpoint with no
rate limit, so a misbehaving or hostile sender could flood a webhook
without bound. RECEIVER_RATE_LIMIT (default 120/min) now caps it, keyed on
client IP plus entrypoint path so one entrypoint cannot exhaust another's
budget. Over-limit requests get 429 with Retry-After.
The limiter deliberately does not reuse postRateLimit: that helper is
POST-only and keys on IP alone, whereas the receiver must count every
method. A test locks that property in.
Config parsing follows the fail-loudly idiom: a set-but-unparseable or
non-positive value aborts startup rather than falling back to the default.
Known limitation, tracked in #88: the key still trusts forwarded headers
unconditionally, so the limit is evadable by rotating X-Forwarded-For until
trusted-proxy gating lands.
check / check (push) Superseded by a newer commit; never tested
Adds an authenticated, CSRF-protected flow that lets a user change their own password from the profile page.
## Route
- New `POST /password` under the `/user/{username}` group in `setupUserRoutes` (`internal/server/routes.go`). That group already applies `CSRF`, `NoCache`, and `RequireAuth`, so the new endpoint inherits all three.
## Handler (`internal/handlers/profile.go`)
- `HandlePasswordChange` enforces own-user access: the `{username}` path parameter must equal the session username (same 403 rule `HandleProfile` uses). This check plus the session lookup is factored into a shared `profileOwnerOrDeny` helper now used by both handlers.
- Parses `current_password`, `new_password`, and `confirm_password` (body size limited via `http.MaxBytesReader`).
- Verifies the current password with `database.VerifyPassword` against the stored hash.
- Requires the new password to be non-empty and equal to the confirmation.
- Hashes the new password with `database.HashPassword` — the same Argon2id helper used to bootstrap the admin user — and persists it on the user row. No new crypto.
- Re-renders the profile page with a clear success or error message. Wrong current password, empty new password, and mismatched confirmation are each rejected with their own message and leave the stored hash unchanged.
## Template (`templates/profile.html`)
- Adds a "Change Password" card with current / new / confirm password fields plus the hidden `csrf_token` (matching the login form's CSRF embedding).
- Renders success/error alerts using the existing `alert-success` / `alert-error` styles. No new CSS classes, so no Tailwind rebuild is required.
## Tests (`internal/handlers/profile_test.go`)
- `TestHandlePasswordChange_Success`: seeds a user, posts a valid change, asserts success message and that the stored hash changed and verifies against the new password.
- `TestHandlePasswordChange_WrongCurrentPassword`: posts a wrong current password, asserts the rejection message and that the stored hash is unchanged.
Validated with `docker build .` (fmt-check, lint, test, build) — exit 0.
Closes#65
Co-authored-by: sneak <sneak@sneak.berlin>
Co-authored-by: Jeffrey Paul <sneak@noreply.example.org>
Reviewed-on: #83
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>
Closes [issue #50](#50)
## Summary
Refactors the Dockerfile to use a separate lint stage with a pinned golangci-lint Docker image, following the pattern used by [sneak/pixa](https://git.eeqj.de/sneak/pixa). This replaces the previous approach of installing golangci-lint via curl in the builder stage.
## Changes
### Dockerfile
- **New `lint` stage** using `golangci/golangci-lint:v2.11.3` (Debian-based, pinned by sha256 digest) as a separate build stage
- **Builder stage** depends on lint via `COPY --from=lint /src/go.sum /dev/null` — build won't proceed unless linting passes
- **Go bumped** from 1.24 to 1.26.1 (`golang:1.26.1-bookworm`, pinned by sha256)
- **golangci-lint bumped** from v1.64.8 to v2.11.3
- All three Docker images (golangci-lint, golang, alpine) pinned by sha256 digest
- Debian-based golangci-lint image used (not Alpine) because mattn/go-sqlite3 CGO does not compile on musl (off64_t)
### Linter Config (.golangci.yml)
- Migrated from v1 to v2 format (`version: "2"` added)
- Removed linters no longer available in v2: `gofmt` (handled by `make fmt-check`), `gosimple` (merged into `staticcheck`), `typecheck` (always-on in v2)
- Same set of linters enabled — no rules weakened
### Code Fixes (all lint issues from v2 upgrade)
- Added package comments to all packages
- Added doc comments to all exported types, functions, and methods
- Fixed unchecked errors flagged by `errcheck` (sqlDB.Close, os.Setenv in tests, resp.Body.Close, fmt.Fprint)
- Fixed unused parameters flagged by `revive` (renamed to `_`)
- Fixed `gosec` G120 warnings: added `http.MaxBytesReader` before `r.ParseForm()` calls
- Fixed `staticcheck` QF1012: replaced `WriteString(fmt.Sprintf(...))` with `fmt.Fprintf`
- Fixed `staticcheck` QF1003: converted if/else chain to tagged switch
- Renamed `DeliveryTask` → `Task` to avoid package stutter (`delivery.Task` instead of `delivery.DeliveryTask`)
- Renamed shadowed builtin `max` parameter to `upperBound` in `cryptoRandInt`
- Used `t.Setenv` instead of `os.Setenv` in tests (auto-restores)
### README.md
- Updated version requirements: Go 1.26+, golangci-lint v2.11+
- Updated Dockerfile description in project structure
## Verification
`docker build .` passes cleanly — formatting check, linting, all tests, and build all succeed.
Co-authored-by: clawbot <clawbot@noreply.git.eeqj.de>
Reviewed-on: #55
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>