Author SHA1 Message Date
clawbot 16d01d5326 nginx: trust X-Forwarded-For only from TRUSTED_PROXIES (closes #64)
check / check (push) Successful in 49s
nginx trusted X-Forwarded-For from every RFC1918 address, so a client
reaching it from one could write a new address on each request and
get a fresh rate-limit allowance. The container's TRUSTED_PROXIES now
names the reverse proxies nginx trusts, none by default.
bin/entrypoint.sh refuses a value with a character no IP address or
CIDR has, and writes one set_real_ip_from line per entry into
/etc/nginx/trusted-proxies.conf, which nginx.conf includes. The
backend is started with TRUSTED_PROXIES=127.0.0.1/32, since nginx is
its only client. The viewport test mounts an empty file there.

Model: opus-5-5
2026-09-29 05:16:37 +00:00
25 changed files with 129 additions and 542 deletions
+2 -4
View File
@@ -6,7 +6,5 @@ jobs:
steps:
# actions/checkout v4.2.2, 2026-02-22
- uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683
# script/cibuild bootstraps, runs every check and builds the
# image. script/bootstrap links what it installs into
# ~/.local/bin, so that has to be on PATH for the rest.
- run: PATH="$HOME/.local/bin:$PATH" script/cibuild
# script/cibuild builds the image, whose stages run every check.
- run: script/cibuild
+1 -3
View File
@@ -72,14 +72,12 @@ RUN addgroup -g 1000 -S netwatch && \
# conf.d; bin/entrypoint.sh says how.
RUN rm /etc/nginx/conf.d/default.conf
COPY nginx.conf /etc/nginx/templates/netwatch.conf.template
COPY security-headers.conf /etc/nginx/security-headers.conf
COPY --from=frontend /app/dist /usr/share/nginx/html
COPY --from=builder /src/netwatch-server /usr/local/bin/netwatch-server
COPY bin/entrypoint.sh /usr/local/bin/entrypoint.sh
# bin/entrypoint.sh creates DATA_DIR at start and gives it and /data to
# the netwatch user, whatever is mounted there.
ENV DATA_DIR=/data/reports
RUN mkdir -p /data/reports && chown -R netwatch:netwatch /data
VOLUME /data
# The default public port; PORT changes it.
+21 -17
View File
@@ -36,12 +36,12 @@ The Go backend in `backend/` has its own `script/` directory and shim Makefile
(see [backend/README.md](backend/README.md)). The root scripts cover both
halves, so the root `make check` fails if either one is broken. We provide:
- `script/bootstrap` — install all dependencies (the pinned node via nvm unless
one new enough for the frontend's dependencies is installed, yarn via
corepack, `yarn install --frozen-lockfile`, the pinned Go unless one at least
as new as `backend/go.mod` asks for is installed, and the Go modules), linking
what it installs itself into `~/.local/bin`, which has to be on `PATH`. It
installs no Go linter and not Docker: `make lint` runs the linter in Docker
- `script/bootstrap` — install all dependencies (pinned node via nvm if needed,
yarn via corepack, `yarn install --frozen-lockfile`, the pinned Go unless one
at least as new as `backend/go.mod` asks for is installed, and the Go
modules), linking what it installs itself into `~/.local/bin`, which has to be
on `PATH`. It installs no Go linter and not Docker: `make lint` runs the
linter in Docker
- `script/setup` — make a fresh clone ready for development: bootstrap plus the
git pre-commit hook
- `script/projectname` — print the project name (used for the Docker image tag)
@@ -65,8 +65,7 @@ halves, so the root `make check` fails if either one is broken. We provide:
`script/check`: it needs Docker and takes minutes.
- `script/docker` — build the image from `Dockerfile` without the build cache,
tagged `netwatch` via `script/projectname`
- `script/cibuild` — CI entrypoint: runs `script/bootstrap` and `script/check`,
then builds the image as `script/docker` does, without the build cache
- `script/cibuild` — CI entrypoint: builds the image
- `script/precommit` — run by the git pre-commit hook; runs `script/check`
- `script/install-precommit` — install the git pre-commit hook
@@ -189,12 +188,9 @@ only inside the container, on `127.0.0.1:8081`. The image:
reverse proxies named in `TRUSTED_PROXIES`, and by default from none
- Sends access logs to stdout
- Caches static assets with immutable headers
- Sends the security headers `REPO_POLICIES.md` requires on every response, as
`security-headers.conf` sets them, in place of the backend's own
- Stores reports in `DATA_DIR`, `/data/reports` by default, on the `/data`
volume. Before the backend starts, the image creates `DATA_DIR` and gives it
and `/data` to user `netwatch` (uid 1000), which the backend runs as, so a
host directory bind-mounted at `/data` ends up owned by uid 1000
volume. The backend runs as user `netwatch` (uid 1000), so a directory
bind-mounted at `/data` must be writable by uid 1000
- Writes buffered reports to disk on `docker stop`, and exits non-zero if nginx
or the backend exits on its own, so the platform restarts it
@@ -204,6 +200,16 @@ What the [upaas](https://git.eeqj.de/sneak/upaas) app for netwatch needs:
- **Port:** container port `8080`.
- **Volume:** container path `/data`; the reports are kept in `/data/reports`.
- **First run:** upaas bind-mounts the host directory it is given and does not
create it, and the backend, which runs as uid 1000, does not start unless it
can write there. Create the directory, owned by uid 1000, before the first
deploy:
```bash
mkdir -p /path/to/data
chown 1000:1000 /path/to/data
```
- **Environment variables:** none is required. An empty one counts as unset, and
one set to a value netwatch cannot use stops the container at start, with the
reason in its log.
@@ -216,10 +222,8 @@ What the [upaas](https://git.eeqj.de/sneak/upaas) app for netwatch needs:
- `CORS_ALLOWED_ORIGINS`, default empty: other origins whose pages may call
the API
- `DEBUG`, default `false`: debug logging
- `DATA_DIR`, default `/data/reports`: the directory the reports are kept
in: `/data` or a path below it, with no `.` or `..` part and no extra `/`.
The container also stops if a part of the path that exists, `/data`
included, is a symbolic link
- `DATA_DIR`, default `/data/reports`: leave unset; reports kept outside
`/data` do not survive a redeploy
- `TRUSTED_PROXIES`, default empty: set it to the address the reverse proxy
in front of the container connects from, as an IP address or CIDR; several
are separated by commas. nginx takes the client address from
+8 -55
View File
@@ -23,67 +23,14 @@ latest run passes.
# Completed Steps
- 2026-09-29: `bin/entrypoint.sh` checks `DATA_DIR` in full before it acts on it
as root (issue #80): `DATA_DIR` must be `/data` or a path below it with no
`.`, `..` or empty part, and no part of it that exists, `/data` included, may
be a symbolic link; anything else stops the start with a message naming
`DATA_DIR`. Only then is `DATA_DIR` created and `/data` given to `netwatch`,
so a refused start no longer creates directories outside `/data`, and
`DATA_DIR=/etc` no longer gives `/etc` to `netwatch`. The `README.md` section
"Running under upaas" says which values are accepted
- 2026-09-29: the container sets up its own data directory (issue #75):
`bin/entrypoint.sh`, still as root, creates `DATA_DIR` if missing and gives it
and `/data` to the `netwatch` user with mode 750 before starting the backend
as that user, so an empty host directory owned by root, or one holding files
from another uid, works with no step on the host. It stops the start instead
when a symbolic link is on the path to `DATA_DIR`, since root would change
whatever the link points to. The `README.md` first-run step that created and
chowned the host directory is gone, and the image no longer sets that
ownership at build time
- 2026-09-29: CI can no longer pass on checks that did not run (issue #37):
`script/cibuild` is now the org model, byte for byte. It runs
`script/bootstrap` and `script/check`, then builds the image with `--no-cache`
and the version from `git describe` as the `VERSION` build argument, where it
used to be a plain `docker build .` whose check steps could come from the
build cache. The workflow puts `~/.local/bin`, where bootstrap links what it
installs, on the step's `PATH`, and bootstrap now installs its pinned node
when the installed one is older than the frontend's dependencies need
- 2026-09-29: `backend/.golangci.yml` re-vendored from `sneak/prompts` (issue
#41): `gomodguard`, deprecated in golangci-lint v2.12.0, is disabled and its
successor `gomodguard_v2` enabled with the org block list, so lint runs print
no deprecation warning. The new file also turns `depguard` on with its
`test-support` rule, which keeps `net/http/httptest` out of non-test code;
netwatch adds no entries of its own to that rule. `backend/script/lint` checks
the new sha256
- 2026-09-29: nginx sends the security headers `REPO_POLICIES.md` requires on
every response (issue #18), including errors, `/assets/` and what it passes on
from the backend, whose own copies it drops so each header goes out once. They
live in `security-headers.conf`, which `nginx.conf` includes. The content
security policy allows no inline script or style, so the status dot's grey in
`src/main.js` is now a class; `connect-src` is `*` because probed hosts
redirect to others, and the browser checks each redirect against it
- 2026-09-29: the request log is bounded (issue #60): the method, URL, protocol,
`User-Agent`, `Referer`, request ID (which chi takes from the client's
`X-Request-Id` header) and client address it writes are each cut to 128 bytes,
the bound the report handler already used, so one request can no longer put
about 1 MiB per field into a log line. That bound and its helper now live in
the `logger` package, shared by both
- 2026-09-29: nginx takes the client address from `X-Forwarded-For` only on
requests from the reverse proxies named in the container's `TRUSTED_PROXIES`
(issue #64), and by default from none, where it trusted every RFC1918 address
before, so a client could write a new address on each request and escape the
rate limit. `bin/entrypoint.sh` writes one `set_real_ip_from` line per entry
into `/etc/nginx/trusted-proxies.conf`, which `nginx.conf` includes, refusing
an entry that is not an IP address or CIDR, as `netwatch-server check-cidr`
finds; it starts the backend with `TRUSTED_PROXIES=127.0.0.1/32`, since nginx
is its only client
- 2026-09-29: report file names can no longer collide (issue #61): each is
`reports-<timestamp>-<number>.jsonl.zst`, where the number goes up by one for
each file the server starts to write, so two flushes in the same millisecond,
such as a flush for size and the final flush at shutdown, each get a file of
their own instead of the second one failing. A failed write uses up its
number, leaving a gap if the file could not be created and otherwise a file
under that number that may be incomplete.
a value with a character no IP address or CIDR has; it starts the backend with
`TRUSTED_PROXIES=127.0.0.1/32`, since nginx is its only client
- 2026-09-29: ready to run under upaas (issue #59): the image has a
`HEALTHCHECK` that requests `/.well-known/healthcheck` through nginx on the
port from `PORT`. The backend no longer reads a bad `PORT` as 0 or a bad
@@ -223,3 +170,9 @@ latest run passes.
(main always green policy)
- Decide what to do with untracked resume.sh: commit it, gitignore it, or delete
it
- Upstream fix needed in `sneak/prompts`: the org-standard `.golangci.yml`
enables `gomodguard`, which golangci-lint v2.12.2 reports as deprecated since
v2.12.0 and replaced by `gomodguard_v2`, so every backend lint run prints a
deprecation warning. The file is standardized and must never be edited in this
repo, so nothing can be done here beyond tracking it — tracked at
<https://git.eeqj.de/sneak/netwatch/issues/41>
+2 -66
View File
@@ -10,20 +10,14 @@ run:
linters:
default: all
enable:
# Successor to the deprecated gomodguard. Named explicitly, rather than
# left to `default: all`, because it carries the module policy below.
- gomodguard_v2
disable:
# Genuinely incompatible with project patterns
- exhaustruct # Requires all struct fields
- depguard # Dependency allow/block lists
- godot # Requires comments to end with periods
- wsl # Deprecated, replaced by wsl_v5
- wrapcheck # Too verbose for internal packages
- varnamelen # Short names like db, id are idiomatic Go
# Deprecated: the warning is attached to the old name, so it is
# silenced by disabling that name, not by enabling the successor.
- wsl # Deprecated, replaced by wsl_v5
- gomodguard # Deprecated, replaced by gomodguard_v2
settings:
lll:
line-length: 88
@@ -34,64 +28,6 @@ linters:
max-complexity: 15
dupl:
threshold: 100
depguard:
# Test-support code must not be compiled into the shipped binary. A
# test-support package exists to hand a test privileges the program
# itself must never have, so a file that is not a test must not import
# one. Test files, and the files inside a package whose directory name
# ends in `test`, are where that code belongs, and are exempt.
#
# The deny list below is the one part of this file a repository is
# expected to extend, and the only part it may. depguard matches an
# import path against a list of prefixes, so it cannot be told "any path
# whose last segment ends in test"; a repository's own test-support
# packages have to be named here one at a time, by full import path,
# under a module path that differs from repository to repository. Add
# them; change nothing else.
rules:
test-support:
list-mode: lax
files:
- "$all"
- "!$test"
- "!**/*test/**"
deny:
- pkg: net/http/httptest
desc: >-
Test-support code belongs in test files and in packages whose
directory name ends in test, not in the shipped binary.
# Only decisions already recorded in the Go package defaults are
# listed here. Every entry matches the module path exactly.
gomodguard_v2:
blocked:
- module: github.com/rs/zerolog
recommendations:
- log/slog
reason: "Structured logging is stdlib log/slog."
# One entry per pre-fork module path, because the later releases
# are separate paths. A prefix match would be shorter but would
# also reach github.com/go-redis/redismock, the test double for
# the successor these entries recommend.
- module: github.com/go-redis/redis
recommendations:
- github.com/redis/go-redis/v9
reason: "Pre-fork module; use the maintained go-redis v9."
- module: github.com/go-redis/redis/v7
recommendations:
- github.com/redis/go-redis/v9
reason: "Pre-fork module; use the maintained go-redis v9."
- module: github.com/go-redis/redis/v8
recommendations:
- github.com/redis/go-redis/v9
reason: "Pre-fork module; use the maintained go-redis v9."
- module: github.com/sergi/go-diff
recommendations:
- github.com/aymanbagabas/go-udiff
reason: "No unified diff output; use go-udiff."
- module: github.com/hexops/gotextdiff
recommendations:
- github.com/aymanbagabas/go-udiff
reason: "Unmaintained fork; use go-udiff."
issues:
max-issues-per-linter: 0
+6 -16
View File
@@ -104,31 +104,21 @@ this server. The image's entrypoint, `bin/entrypoint.sh`, starts the server as
user `netwatch` (uid 1000) with `BIND_ADDRESS=127.0.0.1` and `PORT=8081`, so
only nginx reaches it, and with `TRUSTED_PROXIES=127.0.0.1/32`, so it takes the
client address nginx passes on and no other. `DATA_DIR` is `/data/reports`, on
the `/data` volume; the entrypoint creates it and gives it and `/data` to
`netwatch` before starting the server. nginx replaces the security headers
this server sets with those in the root `security-headers.conf`, so those are
what clients of the image see.
the `/data` volume, which `netwatch` owns.
The container's own `TRUSTED_PROXIES` goes to nginx instead: IP addresses or
CIDRs, separated by commas, of the reverse proxies in front of the container.
nginx takes the client address from `X-Forwarded-For` only on a request from one
of them. Unset or empty, nginx trusts no proxy, and the client address is the
one each request comes from, so every client behind a proxy shares one rate
limit. An entry that is not an IP address or CIDR, such as a hostname or
`1.2.3`, stops the container at start with an error naming `TRUSTED_PROXIES`:
the entrypoint checks each entry with `netwatch-server check-cidr`, which parses
it as this server parses its own `TRUSTED_PROXIES`.
limit. A value with a character no IP address or CIDR has, such as a hostname,
stops the container at start with an error naming `TRUSTED_PROXIES`.
### Report storage
Reports are written as `reports-<timestamp>-<number>.jsonl.zst` files in
`DATA_DIR`. The timestamp is in UTC to the millisecond, so the names sort by
time. The number starts at 1 when the server starts and goes up by one for each
file the server starts to write, so two files written in the same millisecond
still get different names. A failed write uses up its number, leaving a gap in
the numbers if the file could not be created and otherwise a file under that
number that may be incomplete. Each file contains one JSON object per line,
compressed with zstd. Files are created with `O_EXCL` to prevent overwrites.
Reports are written as `reports-<timestamp>.jsonl.zst` files in `DATA_DIR`.
Each file contains one JSON object per line, compressed with zstd. Files are
created with `O_EXCL` to prevent overwrites.
### Report limits
-16
View File
@@ -2,9 +2,6 @@
package main
import (
"fmt"
"os"
"sneak.berlin/go/netwatch/internal/config"
"sneak.berlin/go/netwatch/internal/globals"
"sneak.berlin/go/netwatch/internal/handlers"
@@ -25,19 +22,6 @@ var (
)
func main() {
// "netwatch-server check-cidr CIDR" exits 1, with the error, if
// this server would refuse CIDR in its TRUSTED_PROXIES.
// bin/entrypoint.sh runs it on each entry it gives nginx.
if len(os.Args) == 3 && os.Args[1] == "check-cidr" {
_, err := middleware.ParseTrustedProxies(os.Args[2:])
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
return
}
globals.Appname = Appname
globals.Version = Version
globals.Buildarch = Buildarch
+3
View File
@@ -2,6 +2,9 @@ package handlers
import "log/slog"
// MaxLoggedFieldBytes exposes the log bound to the external tests.
const MaxLoggedFieldBytes = maxLoggedFieldBytes
// NewForTest builds a Handlers around a report sink and logger,
// bypassing the fx graph so handler behaviour (including the
// storage failure path) is exercisable in unit tests.
+18 -4
View File
@@ -5,10 +5,14 @@ import (
"errors"
"net/http"
"sneak.berlin/go/netwatch/internal/logger"
"sneak.berlin/go/netwatch/internal/reportbuf"
)
// maxLoggedFieldBytes bounds untrusted text (string fields,
// decode error text) before it is logged, so a caller cannot
// inflate log volume with an oversized value.
const maxLoggedFieldBytes = 128
type reportSample struct {
T int64 `json:"t"`
Latency *int `json:"latency"`
@@ -79,7 +83,7 @@ func (s *Handlers) decodeErrorStatus(err error) int {
// The decoder's error text can quote request bytes (a whole
// oversized number, for example), so it is bounded too.
s.log.Error("failed to decode report",
"error", logger.BoundedForLog(err.Error()),
"error", boundedForLog(err.Error()),
)
return http.StatusBadRequest
@@ -111,10 +115,20 @@ func (s *Handlers) logReportReceived(rpt report) {
}
s.log.Info("report received",
"client_id", logger.BoundedForLog(rpt.ClientID),
"timestamp", logger.BoundedForLog(rpt.Timestamp),
"client_id", boundedForLog(rpt.ClientID),
"timestamp", boundedForLog(rpt.Timestamp),
"host_count", len(rpt.Hosts),
"total_samples", totalSamples,
"geo_bytes", len(rpt.Geo),
)
}
// boundedForLog truncates an untrusted string to a fixed byte
// bound so an attacker-controlled field cannot dominate the log.
func boundedForLog(s string) string {
if len(s) > maxLoggedFieldBytes {
return s[:maxLoggedFieldBytes]
}
return s
}
+5 -6
View File
@@ -12,7 +12,6 @@ import (
"testing"
"sneak.berlin/go/netwatch/internal/handlers"
"sneak.berlin/go/netwatch/internal/logger"
"sneak.berlin/go/netwatch/internal/middleware"
"sneak.berlin/go/netwatch/internal/reportbuf"
)
@@ -175,7 +174,7 @@ func TestHandleReportDoesNotLogRawGeo(t *testing.T) {
func TestHandleReportLogsClientIDCutToBound(t *testing.T) {
t.Parallel()
long := strings.Repeat("c", 2*logger.MaxLoggedFieldBytes)
long := strings.Repeat("c", 2*handlers.MaxLoggedFieldBytes)
var logbuf bytes.Buffer
@@ -198,16 +197,16 @@ func TestHandleReportLogsClientIDCutToBound(t *testing.T) {
t.Fatalf("log line not JSON: %v (%q)", err, logbuf.String())
}
want := long[:logger.MaxLoggedFieldBytes]
want := long[:handlers.MaxLoggedFieldBytes]
if logged["client_id"] != want {
t.Fatalf("logged client_id not cut to %d bytes: %q",
logger.MaxLoggedFieldBytes, logged["client_id"])
handlers.MaxLoggedFieldBytes, logged["client_id"])
}
if logged["timestamp"] != want {
t.Fatalf("logged timestamp not cut to %d bytes: %q",
logger.MaxLoggedFieldBytes, logged["timestamp"])
handlers.MaxLoggedFieldBytes, logged["timestamp"])
}
}
@@ -216,7 +215,7 @@ func TestHandleReportDecodeErrorLogIsBounded(t *testing.T) {
// A number too large for its int64 field makes the decoder's
// error text quote the whole number.
huge := strings.Repeat("9", 2*logger.MaxLoggedFieldBytes)
huge := strings.Repeat("9", 2*handlers.MaxLoggedFieldBytes)
var logbuf bytes.Buffer
-15
View File
@@ -11,21 +11,6 @@ import (
"go.uber.org/fx"
)
// MaxLoggedFieldBytes bounds untrusted text (request fields,
// header values, decode error text) before it is logged, so a
// caller cannot inflate log volume with an oversized value.
const MaxLoggedFieldBytes = 128
// BoundedForLog truncates an untrusted string to a fixed byte
// bound so an attacker-controlled field cannot dominate the log.
func BoundedForLog(s string) string {
if len(s) > MaxLoggedFieldBytes {
return s[:MaxLoggedFieldBytes]
}
return s
}
// Params defines the dependencies for Logger.
type Params struct {
fx.In
@@ -29,3 +29,7 @@ func ClientIP(
) string {
return clientIP(remoteAddr, header, trusted)
}
func ParseTrustedProxies(cidrs []string) ([]netip.Prefix, error) {
return parseTrustedProxies(cidrs)
}
+15 -18
View File
@@ -64,7 +64,7 @@ func New(
_ fx.Lifecycle,
params Params,
) (*Middleware, error) {
trusted, err := ParseTrustedProxies(params.Config.TrustedProxies)
trusted, err := parseTrustedProxies(params.Config.TrustedProxies)
if err != nil {
return nil, err
}
@@ -77,11 +77,9 @@ func New(
return s, nil
}
// ParseTrustedProxies converts the TRUSTED_PROXIES entries into
// prefixes, failing fast on any malformed entry. Each entry must be
// a CIDR; a lone address is refused. "netwatch-server check-cidr"
// runs it too.
func ParseTrustedProxies(cidrs []string) ([]netip.Prefix, error) {
// parseTrustedProxies converts the TRUSTED_PROXIES entries into
// prefixes, failing fast on any malformed entry.
func parseTrustedProxies(cidrs []string) ([]netip.Prefix, error) {
prefixes := make([]netip.Prefix, 0, len(cidrs))
for _, cidr := range cidrs {
@@ -189,10 +187,7 @@ func addrInAny(s string, trusted []netip.Prefix) bool {
}
// Logging returns middleware that logs each request with
// timing, status code, and client information. Every string
// taken from the request is cut to logger.MaxLoggedFieldBytes,
// including the request ID, which chi takes from the client's
// X-Request-Id header when one is sent.
// timing, status code, and client information.
func (s *Middleware) Logging() func(http.Handler) http.Handler {
return func(next http.Handler) http.Handler {
return http.HandlerFunc(
@@ -205,19 +200,21 @@ func (s *Middleware) Logging() func(http.Handler) http.Handler {
latency := time.Since(start)
s.log.InfoContext(ctx, "request",
"request_start", start,
"method", logger.BoundedForLog(r.Method),
"url", logger.BoundedForLog(r.URL.String()),
"useragent", logger.BoundedForLog(r.UserAgent()),
"method", r.Method,
"url", r.URL.String(),
"useragent", r.UserAgent(),
"request_id",
logger.BoundedForLog(middleware.GetReqID(ctx)),
"referer", logger.BoundedForLog(r.Referer()),
"proto", logger.BoundedForLog(r.Proto),
ctx.Value(
middleware.RequestIDKey,
),
"referer", r.Referer(),
"proto", r.Proto,
"remote_ip",
logger.BoundedForLog(clientIP(
clientIP(
r.RemoteAddr,
r.Header,
s.trustedProxies,
)),
),
"status", lrw.statusCode,
"latency_ms",
latency.Milliseconds(),
+2 -68
View File
@@ -13,10 +13,7 @@ import (
"testing/synctest"
"time"
"sneak.berlin/go/netwatch/internal/logger"
"sneak.berlin/go/netwatch/internal/middleware"
chimiddleware "github.com/go-chi/chi/v5/middleware"
)
const (
@@ -39,31 +36,14 @@ func mustPrefixes(t *testing.T, cidrs ...string) []netip.Prefix {
return prefixes
}
// TestParseTrustedProxiesRejectsMalformed includes entries nginx would
// read as another address or look up as a hostname, in the CIDR form
// bin/entrypoint.sh gives "netwatch-server check-cidr".
func TestParseTrustedProxiesRejectsMalformed(t *testing.T) {
t.Parallel()
for _, cidr := range []string{
"not-a-cidr", "10.0.0.1", "1.2.3/32", "172.30/32", "10/32",
"cafe/32", "999.1.1.1/32", "10.0.0.0/33", "::1/129",
"fe80::1%eth0/128",
} {
_, err := middleware.ParseTrustedProxies([]string{cidr})
_, err := middleware.ParseTrustedProxies([]string{"not-a-cidr"})
if err == nil || !strings.Contains(err.Error(), "TRUSTED_PROXIES") {
t.Errorf("%q: error = %v, want one naming TRUSTED_PROXIES",
cidr, err)
t.Fatalf("error = %v, want one naming TRUSTED_PROXIES", err)
}
}
}
func TestParseTrustedProxiesAcceptsCIDRs(t *testing.T) {
t.Parallel()
mustPrefixes(t, "172.17.0.1/32", "10.0.0.0/8", "2001:db8::1/128",
"2001:db8::/32", "::ffff:192.0.2.1/128")
}
type clientIPCase struct {
name string
@@ -323,52 +303,6 @@ func TestRecovererRepanicsOnAbortHandler(t *testing.T) {
}
}
// TestLoggingCutsRequestStringsToBound sends an over-long URL and
// over-long header values, and checks the request log writes each
// one cut to logger.MaxLoggedFieldBytes.
func TestLoggingCutsRequestStringsToBound(t *testing.T) {
t.Parallel()
long := strings.Repeat("a", 2*logger.MaxLoggedFieldBytes)
var logbuf bytes.Buffer
mw := middleware.NewWithLogger(
slog.New(slog.NewJSONHandler(&logbuf, nil)),
)
handler := chimiddleware.RequestID(mw.Logging()(okHandler()))
req := httptest.NewRequestWithContext(t.Context(),
http.MethodGet, "/"+long, http.NoBody)
req.Header.Set("User-Agent", long)
req.Header.Set("Referer", long)
req.Header.Set("X-Request-Id", long)
handler.ServeHTTP(httptest.NewRecorder(), req)
var logged map[string]any
err := json.Unmarshal(logbuf.Bytes(), &logged)
if err != nil {
t.Fatalf("log line not JSON: %v (%q)", err, logbuf.String())
}
want := map[string]string{
"url": ("/" + long)[:logger.MaxLoggedFieldBytes],
"useragent": long[:logger.MaxLoggedFieldBytes],
"referer": long[:logger.MaxLoggedFieldBytes],
"request_id": long[:logger.MaxLoggedFieldBytes],
}
for field, value := range want {
if logged[field] != value {
t.Errorf("logged %s = %q, want it cut to %d bytes",
field, logged[field], logger.MaxLoggedFieldBytes)
}
}
}
// okHandler stands in for the route a middleware guards.
func okHandler() http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
@@ -1,15 +1,7 @@
package reportbuf
import "time"
// Flush writes the buffered reports to a file now, as the periodic
// flush does, so tests need not wait a minute for it.
func (b *Buffer) Flush() error {
return b.flushLocked()
}
// StopClock makes every report file the buffer writes from now on
// carry the timestamp at, as if all were written in one millisecond.
func (b *Buffer) StopClock(at time.Time) {
b.now = func() time.Time { return at }
}
+4 -16
View File
@@ -14,7 +14,6 @@ import (
"path/filepath"
"strings"
"sync"
"sync/atomic"
"time"
"sneak.berlin/go/netwatch/internal/config"
@@ -31,8 +30,7 @@ const (
dirPerms fs.FileMode = 0o750
filePerms fs.FileMode = 0o640
// Report files are named filePrefix + timestamp + "-" + number +
// fileSuffix; see writeFile.
// Report files are named filePrefix + timestamp + fileSuffix.
filePrefix = "reports-"
fileSuffix = ".jsonl.zst"
)
@@ -58,12 +56,6 @@ type Buffer struct {
log *slog.Logger
maxBytes int64
mu sync.Mutex
// now is the clock report files are named by: time.Now, except
// in tests that need two flushes to share a timestamp.
now func() time.Time
// seq numbers the report files, so that two named in the same
// millisecond still get different names.
seq atomic.Uint64
stopOnce sync.Once
// usedBytes is what Append checks against maxBytes: the size
// of the report files in dataDir, plus the reports not yet
@@ -87,7 +79,6 @@ func New(
done: make(chan struct{}),
log: params.Logger.Get(),
maxBytes: params.Config.DataDirMaxBytes,
now: time.Now,
}
lc.Append(fx.Hook{
@@ -220,14 +211,11 @@ func (b *Buffer) drainBuf() []byte {
// writeFile creates a timestamped zstd-compressed JSONL file
// in the data directory.
func (b *Buffer) writeFile(data []byte) error {
// The timestamp comes first, so the names sort by time; the number
// after it tells apart files named in the same millisecond.
ts := b.now().UTC().Format("2006-01-02T15-04-05.000Z")
name := fmt.Sprintf("%s%s-%d%s", filePrefix, ts, b.seq.Add(1), fileSuffix)
path := filepath.Join(b.dataDir, name)
ts := time.Now().UTC().Format("2006-01-02T15-04-05.000Z")
path := filepath.Join(b.dataDir, filePrefix+ts+fileSuffix)
// path is built from the operator-supplied dataDir plus a
// generated timestamp and number, so it carries no external input.
// generated timestamp, so it carries no external input.
f, err := os.OpenFile( //nolint:gosec // see comment above
path,
os.O_WRONLY|os.O_CREATE|os.O_EXCL,
+8 -77
View File
@@ -3,11 +3,9 @@ package reportbuf_test
import (
"encoding/json"
"errors"
"fmt"
"io/fs"
"os"
"path/filepath"
"slices"
"strconv"
"strings"
"sync"
@@ -20,7 +18,6 @@ import (
"sneak.berlin/go/netwatch/internal/logger"
"sneak.berlin/go/netwatch/internal/reportbuf"
"github.com/klauspost/compress/zstd"
"go.uber.org/fx"
"go.uber.org/fx/fxtest"
)
@@ -213,6 +210,10 @@ func TestWrittenReportsCountAtFileSize(t *testing.T) {
t.Fatalf("flush: %v", err)
}
// The second report is written at shutdown, and must not land in
// the first file's millisecond (see TestWrittenReportsKeepCounting).
time.Sleep(time.Millisecond)
err = buf.Append(report)
if err != nil {
t.Fatalf("second report, after the first was written: %v", err)
@@ -253,6 +254,10 @@ func TestWrittenReportsKeepCounting(t *testing.T) {
t.Fatalf("with %d bytes of report files: %v", used, err)
}
// Report files are named to the millisecond; two in the same
// one collide (https://git.eeqj.de/sneak/netwatch/issues/61).
time.Sleep(time.Millisecond)
err = buf.Flush()
if err != nil {
t.Fatalf("flush: %v", err)
@@ -310,43 +315,6 @@ func TestConcurrentAppendsStopAtCap(t *testing.T) {
}
}
// TestTwoFlushesInOneMillisecond flushes twice within one millisecond,
// as a flush for size and the final flush at shutdown can: each flush
// must write a file of its own, and the files must hold every report.
func TestTwoFlushesInOneMillisecond(t *testing.T) {
const flushes = 2
dir := t.TempDir()
t.Setenv("DATA_DIR", dir)
buf := startBuffer(t)
buf.StopClock(time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC))
for id := 1; id <= flushes; id++ {
err := buf.Append(map[string]int{"id": id})
if err != nil {
t.Fatalf("append report %d: %v", id, err)
}
err = buf.Flush()
if err != nil {
t.Fatalf("flush %d: %v", id, err)
}
}
files := readReportFiles(t, dir)
if len(files) != flushes {
t.Fatalf("%d report files after %d flushes", len(files), flushes)
}
for id := 1; id <= flushes; id++ {
want := fmt.Sprintf(`{"id":%d}`+"\n", id)
if !slices.Contains(files, want) {
t.Fatalf("no report file holds report %d alone", id)
}
}
}
// reportFilesBytes returns the total size of the report files in dir.
func reportFilesBytes(t *testing.T, dir string) int64 {
t.Helper()
@@ -370,43 +338,6 @@ func reportFilesBytes(t *testing.T, dir string) int64 {
return total
}
// readReportFiles returns the decompressed contents of each report
// file in dir.
func readReportFiles(t *testing.T, dir string) []string {
t.Helper()
files := os.DirFS(dir)
names, err := fs.Glob(files, "reports-*.jsonl.zst")
if err != nil {
t.Fatalf("list report files: %v", err)
}
dec, err := zstd.NewReader(nil)
if err != nil {
t.Fatalf("create zstd decoder: %v", err)
}
defer dec.Close()
contents := make([]string, 0, len(names))
for _, name := range names {
compressed, readErr := fs.ReadFile(files, name)
if readErr != nil {
t.Fatalf("read %s: %v", name, readErr)
}
data, decErr := dec.DecodeAll(compressed, nil)
if decErr != nil {
t.Fatalf("decompress %s: %v", name, decErr)
}
contents = append(contents, string(data))
}
return contents
}
func writeBytes(t *testing.T, path string, n int) {
t.Helper()
+1 -1
View File
@@ -14,7 +14,7 @@ set -eu
ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
GOLANGCI_CONFIG_SHA256="a79b63a254602a5318db5d0e9a06bc71b84bf0c1d896305229d8bfed1d1b1776"
GOLANGCI_CONFIG_SHA256="021cc83f4e6fc7c31b95b34b846723dfcf20b66b7baeea1dc40406e643346bcb"
main() {
cd "$ROOT"
+13 -62
View File
@@ -35,72 +35,23 @@ fi
# TRUSTED_PROXIES names the reverse proxies in front of the container,
# as IP addresses or CIDRs separated by commas. nginx takes the client
# address from X-Forwarded-For only on a request from one of them, so
# unset or empty, it trusts no one. nginx.conf includes the file written
# here, one set_real_ip_from line per entry.
#
# nginx looks up an entry it cannot read as an address as a hostname,
# and trusts what it finds (1.2.3 is found as 1.2.0.3). So each entry
# is made a CIDR, a lone address getting /128 if it is IPv6 and /32 if
# not, and netwatch-server checks it with the parsing it gives its own
# TRUSTED_PROXIES. Its error, naming the CIDR, is dropped for the one
# below, naming the entry as written. set -f keeps a * in an entry from
# becoming a list of file names.
# unset or empty, it trusts no one. nginx would look up a hostname at
# start and trust whatever address it found, so a value with a
# character no address has stops the container here. An entry such as
# 999.1.1.1 gets past this, and nginx refuses it at start as a
# hostname it cannot find.
TRUSTED_PROXIES="${TRUSTED_PROXIES:-}"
set -f
for proxy in $(printf '%s' "$TRUSTED_PROXIES" | tr ',' ' '); do
case "$proxy" in
*/*) cidr="$proxy" ;;
*:*) cidr="$proxy/128" ;;
*) cidr="$proxy/32" ;;
esac
if ! netwatch-server check-cidr "$cidr" 2> /dev/null; then
case "$TRUSTED_PROXIES" in
*[!0-9A-Fa-f.:/,\ ]*)
echo "entrypoint: TRUSTED_PROXIES must be IP addresses or CIDRs" \
"separated by commas; '$proxy' is neither" >&2
"separated by commas, not '$TRUSTED_PROXIES'" >&2
exit 1
fi
echo "set_real_ip_from $cidr;"
done > /etc/nginx/trusted-proxies.conf
# netwatch-server keeps its report files in DATA_DIR, on the /data
# volume, which may be a host directory owned by root or by another
# uid. /data and everything in it are given to the netwatch user here,
# and /data and DATA_DIR get the mode the server gives a directory it
# creates, so the host directory needs no preparing.
#
# This runs as root, so nothing is created or changed until DATA_DIR is
# known to be /data or a path below it, with no '.', '..' or empty
# part, and no part of it that exists, /data included, is a symbolic
# link: the netwatch user can put one in /data, and root would follow
# it anywhere in the container. Nothing else runs in the container yet,
# so no link can appear after the check.
export DATA_DIR="${DATA_DIR:-/data/reports}"
data_dir_ok() {
# With a / added at the end, a last part of '.' or '..', and a / at
# the end, match these patterns too.
case "$DATA_DIR/" in
*/./* | */../* | *//*) return 1 ;;
/data/*) ;;
*) return 1 ;;
;;
esac
# Each part from DATA_DIR up to /data. [ -L ] is false for a part
# that does not exist.
dir="$DATA_DIR"
while [ "$dir" != /data ]; do
[ -L "$dir" ] && return 1
dir="${dir%/*}"
done
[ ! -L /data ]
}
if ! data_dir_ok; then
echo "entrypoint: DATA_DIR must be /data or a path below it, with no" \
"'.', '..', extra '/' or symbolic link on it, not '$DATA_DIR'" >&2
exit 1
fi
mkdir -p "$DATA_DIR" || exit 1
# -h: a symbolic link in /data is itself given to netwatch, not what it
# points to.
chown -R -h netwatch:netwatch /data || exit 1
chmod 750 /data "$DATA_DIR" || exit 1
# nginx.conf includes this file; an empty one trusts no proxy.
for proxy in $(echo "$TRUSTED_PROXIES" | tr ',' ' '); do
echo "set_real_ip_from $proxy;"
done > /etc/nginx/trusted-proxies.conf
# A stop signal is only noted here; the loop below acts on it.
stop_requested=""
-16
View File
@@ -8,11 +8,6 @@ server {
# Keep the nginx version out of the Server header and error pages.
server_tokens off;
# The security headers, on every response. An add_header in a
# location drops every add_header from here, so a location with one
# of its own includes this file again.
include /etc/nginx/security-headers.conf;
root /usr/share/nginx/html;
index index.html;
@@ -37,7 +32,6 @@ server {
location /assets/ {
expires 1y;
add_header Cache-Control "public, immutable";
include /etc/nginx/security-headers.conf;
}
# netwatch-server, the Go backend, runs in the same container and
@@ -51,16 +45,6 @@ server {
proxy_set_header X-Forwarded-For $remote_addr;
proxy_set_header X-Forwarded-Proto $scheme;
# netwatch-server sets the same security headers on its own
# responses. Its copies are dropped so that each header goes out
# once, as security-headers.conf sets it.
proxy_hide_header Strict-Transport-Security;
proxy_hide_header Content-Security-Policy;
proxy_hide_header X-Frame-Options;
proxy_hide_header X-Content-Type-Options;
proxy_hide_header Referrer-Policy;
proxy_hide_header Permissions-Policy;
location /api/ {
proxy_pass http://127.0.0.1:8081;
}
+7 -25
View File
@@ -3,12 +3,12 @@
# this repo. Idempotent: every install is guarded by a check so already
# installed tools are skipped. Base tooling comes from nix, apt, brew,
# or apk (detected in that order); assumes nothing is present. Node is
# used directly if it is at least NODE_MIN_VERSION; otherwise it is
# installed at a pinned version via nvm (installing nvm itself first,
# from a hash-verified release archive, never curl | sh). Go, with its
# gofmt, is used directly if it is at least the version backend/go.mod
# asks for; otherwise the pinned Go release is installed from its
# hash-verified archive.
# used directly if installed; otherwise it is installed at a pinned
# version via nvm (installing nvm itself first, from a hash-verified
# release archive, never curl | sh). Go, with its gofmt, is used
# directly if it is at least the version backend/go.mod asks for;
# otherwise the pinned Go release is installed from its hash-verified
# archive.
#
# What this script installs outside the system package manager lives
# under $HOME and is linked into ~/.local/bin, where make and the git
@@ -23,10 +23,6 @@ ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
# Pinned versions, 2026-07-07
NODE_VERSION="22.17.0"
# The oldest node the frontend's dependencies accept: the "engines"
# field of puppeteer-core 25.5.0, the most demanding of them, asks for
# 22.12.0 or newer, 2026-09-29. An older installed node is not used.
NODE_MIN_VERSION="22.12.0"
NVM_VERSION="0.40.3"
# sha256 of https://github.com/nvm-sh/nvm/archive/refs/tags/v0.40.3.tar.gz
NVM_SHA256="5f4d6aaa04a177dc93c985e31dbc411ab6b8c6e1e21d8015dbc1372625fcd1d0"
@@ -140,22 +136,8 @@ ensure_nvm() {
rm -rf "$tmp"
}
# node_ok: the node on PATH is at least NODE_MIN_VERSION. node itself
# compares the two: major, then minor, then patch.
node_ok() {
if missing node; then return 1; fi
node -e '
const have = process.versions.node.split(".").map(Number);
const want = process.argv[1].split(".").map(Number);
for (let i = 0; i < 3; i++) {
if (have[i] !== want[i]) process.exit(have[i] > want[i] ? 0 : 1);
}
' "$NODE_MIN_VERSION"
}
# ensure_node: unless node_ok, install NODE_VERSION and link its node.
ensure_node() {
if node_ok; then return 0; fi
if ! missing node; then return 0; fi
ensure_nvm
nvm_sh "nvm install $NODE_VERSION"
link_bin "$HOME/.nvm/versions/node/v$NODE_VERSION/bin/node" node
+6 -20
View File
@@ -1,29 +1,15 @@
#!/bin/sh
# script/cibuild: run the CI build. It bootstraps first: a CI runner
# checks out and runs this and nothing else, and script/fmt-check runs
# the formatter on the host, which a pristine checkout cannot do.
# --no-cache for the same reason as script/docker: the gate phases the
# final stage depends on are RUN steps, and a cached one is a check that
# did not run.
# script/cibuild: run the CI build: build the one image from Dockerfile,
# whose stages run the checks as build steps (the backend's fmt-check,
# lint and tests, and the frontend's test, lint and fmt-check). This is
# the only build step the Gitea workflow runs.
set -eu
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd -P)"
ROOT="$(cd "$SCRIPT_DIR/.." && pwd -P)"
ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
main() {
cd "$ROOT"
"$SCRIPT_DIR/bootstrap"
"$SCRIPT_DIR/check"
# Own line: a failing command substitution inside an argument does
# not trip `set -e`, so the inline form degrades silently to an
# empty constant. VERSION is computed here because .dockerignore
# excludes .git, so `git describe` in a build stage yields an empty
# version without failing.
version="$(git describe --tags --always --dirty 2>/dev/null || true)"
[ -n "$version" ] || version="unknown"
docker build --no-cache \
--build-arg VERSION="$version" \
-t "$("$SCRIPT_DIR/projectname")" .
timeout 300 docker build .
}
main "$@"
+1 -3
View File
@@ -64,15 +64,13 @@ main() {
# nginx.conf is a template: the image renders it over its own
# default.conf, with the same port and limit bin/entrypoint.sh uses.
# The empty file it includes trusts no proxy, as bin/entrypoint.sh
# writes it when TRUSTED_PROXIES is unset. nginx.conf also includes
# the security headers, so the page runs under the shipped policy.
# writes it when TRUSTED_PROXIES is unset.
docker run -d --rm --name "$SERVER" \
--network "$NETWORK" --network-alias netwatch \
-e PORT=8080 -e NGINX_ENVSUBST_FILTER='^PORT$' \
-v "$ROOT/dist:/usr/share/nginx/html:ro" \
-v "$ROOT/nginx.conf:/etc/nginx/templates/default.conf.template:ro" \
-v /dev/null:/etc/nginx/trusted-proxies.conf:ro \
-v "$ROOT/security-headers.conf:/etc/nginx/security-headers.conf:ro" \
"$SERVER_IMAGE" > /dev/null
# The image's own entrypoint already exposes CDP on 9222 and passes
-24
View File
@@ -1,24 +0,0 @@
# The security headers REPO_POLICIES.md requires on every response.
# nginx.conf includes this file, which Dockerfile copies to
# /etc/nginx/security-headers.conf. always sends each header on error
# responses too.
add_header Strict-Transport-Security "max-age=31536000; includeSubDomains" always;
# Scripts and styles load only from the page's own origin. Inline ones
# are blocked, style attributes in markup included, so style elements
# through classes or element.style. data: images are for the favicon
# in index.html. connect-src is * because the browser checks each probe in
# src/main.js against it, and also every redirect the probe follows,
# and several of those hosts redirect to others; a list of hosts here
# would block those probes. It also covers the reports the page sends
# to its own origin.
add_header Content-Security-Policy "default-src 'self'; connect-src *; img-src 'self' data:; object-src 'none'; base-uri 'none'; form-action 'none'; frame-ancestors 'none'" always;
add_header X-Frame-Options DENY always;
add_header X-Content-Type-Options nosniff always;
# The probed hosts are not told where the page is served from.
add_header Referrer-Policy no-referrer always;
add_header Permissions-Policy "accelerometer=(), camera=(), display-capture=(), geolocation=(), gyroscope=(), magnetometer=(), microphone=(), midi=(), payment=(), usb=()" always;
+1 -1
View File
@@ -716,7 +716,7 @@ function hostRowHTML(host, index, showPin = true) {
${pinBtn}
<div class="w-[420px] flex-shrink-0 grid grid-cols-[minmax(0,1fr)_auto] items-center">
<div class="flex items-center gap-2 min-w-[200px]">
<div class="w-3 h-3 rounded-full flex-shrink-0 bg-[#6b7280]"></div>
<div class="w-3 h-3 rounded-full flex-shrink-0" style="background-color: ${latencyHex(null)}"></div>
<span class="font-medium text-white truncate">${host.name}</span>
</div>
<div class="latency-value text-4xl font-bold tabular-nums text-right mt-3" data-host="${index}">