Logging in returns to the page that was asked for (closes #384 )

RequireAuth now sends a logged-out GET to /pages/login with its path and query in a `next` parameter. The login form carries it as a hidden field, and a successful login redirects there when it is a path on this site; anything else, plain or percent-encoded, goes to `/`, which leads to the webhook list. A browser already logged in that opens the login page goes to the same place. The navigation bar on the login page no longer links to the login page. Model: opus-5-5
Commit the Alpine.js tarball in 3p/ and extract it at build time (closes #345 )
2026-10-01 20:45:57 +00:00 · 2026-10-01 22:44:41 +02:00
33 changed files with 387 additions and 433 deletions
@@ -3,10 +3,8 @@
 # stage of the Dockerfile.
 .git/
 bin/
-# Third-party browser assets are fetched and hash-verified inside the build by
-# script/fetch-assets. Excluding any host copy keeps a developer's working tree
-# from supplying the bytes that get shipped. The script and its
-# static/vendor.sha256 manifest stay in the context.
+# Extracted from 3p/ by `make assets` inside the build; a host copy is not
+# needed. The tarball in 3p/ must stay in the context.
 static/js/alpine.min.js
 *.md
 LICENSE
@@ -46,7 +46,6 @@ temp/
 # CI cache barrier, written into the build context by the check workflow
 .ci-fingerprint

-# Third-party browser assets, fetched and hash-verified by
-# script/fetch-assets against static/vendor.sha256. Not committed:
-# REPO_POLICIES.md forbids minified bundles in version control.
-/static/js/alpine.min.js 
+# Alpine.js, extracted by `make assets` from its tarball in 3p/, which is
+# what is committed.
+/static/js/alpine.min.js
@@ -51,15 +51,8 @@ RUN go mod download
 # the lint stage above.
 COPY . .

-# Fetch the third-party browser assets the UI serves. They are not committed
-# (REPO_POLICIES.md forbids minified bundles in version control) and
-# .dockerignore keeps any host copy out of the build context, so this step is
-# the only way they enter the image. Each download is checked against a
-# hardcoded sha256 and the build fails on mismatch; make test re-checks the
-# hashes against the bytes go:embed actually put in the binary.
-RUN script/fetch-assets
-
-# Run tests and build
+# Run tests and build. Both first run script/assets, which extracts Alpine.js
+# from its tarball in 3p/.
 RUN make test

 # Version stamped into the binary. .dockerignore excludes .git/, so
@@ -67,8 +60,8 @@ RUN make test
 # host and passes it in. The default is what a bare `docker build .`
 # with no --build-arg gets, and it names no tag the tree may not be at.
 #
-# Declared here, below the test and asset steps, so a changed version
-# does not invalidate their cached layers.
+# Declared here, below the test step, so a changed version does not
+# invalidate its cached layer.
 ARG VERSION=unknown

 RUN make build VERSION="$VERSION"
@@ -28,7 +28,7 @@ setup:
 	@script/setup

 assets:
-	@script/fetch-assets
+	@script/assets

 test:
 	@script/test
@@ -45,13 +45,13 @@ fmt-check:
 check:
 	@script/check

-build:
+build: assets
 	go build -ldflags '$(strip -X main.version=$(VERSION) $(GO_LDFLAGS))' -o bin/webhooker ./cmd/webhooker

 run: build
 	./bin/webhooker

-dev:
+dev: assets
 	go run ./cmd/webhooker

 deps:
@@ -21,9 +21,6 @@ before deploying one.
 - Go 1.26.1+ (the version in `go.mod`)
 - Docker (for linting, for the test stage of the CI gate, and for
  containerized deployment)
- `curl`, used by `script/fetch-assets` to download the third-party
-  browser assets, which are not committed (`make bootstrap` installs
-  it if missing)

 golangci-lint is not a prerequisite and must not be installed on the
 host: `script/bootstrap` does not install it, and `make lint` runs the
@@ -36,9 +33,7 @@ digest-pinned linter image via `Dockerfile.lint`.
 git clone https://git.eeqj.de/sneak/webhooker.git
 cd webhooker

-# Install Go dependencies and the third-party browser assets.
-# `make deps` alone is not enough: it only runs go mod download/tidy,
-# and the checks below need the fetched assets.
+# Install the Go toolchain if missing, and the Go dependencies
 make bootstrap

 # Run all checks (test, lint, format check)
@@ -58,7 +53,7 @@ make docker
 ```bash
 make bootstrap  # Install all dependencies (idempotent)
 make setup      # Bootstrap + install git pre-commit hook
-make assets     # Fetch + verify third-party browser assets
+make assets     # Extract Alpine.js from 3p/ (test, check, build, dev run it)
 make fmt        # Format code (gofmt + goimports)
 make fmt-check  # Fail if gofmt would change anything (writes nothing)
 make lint       # Run golangci-lint in Docker (Dockerfile.lint)
@@ -1221,14 +1216,15 @@ This repository adheres to the
 standard: normalized scripts in `script/` are the entrypoints for the
 development workflow. Ten of the Makefile's seventeen targets are thin
 shims that call them; `build`, `run`, `dev`, `deps`, `clean`, `css` and
-`version` are inline commands with no script behind them, though
-`build` and `version` both take their value from `script/version`.
+`version` are inline commands with no script behind them, though `build`,
+`run` and `dev` first run `script/assets`, and `build` and `version` both
+take their value from `script/version`.

-`make check` needs the third-party browser assets in `static/`, which
-are not committed, so run `make bootstrap` (or just `make assets`) once
-after cloning. Without them the tests fail with a message naming that
-remedy. `make check` does not fetch them itself because it must not
-change any files in the repo.
+`script/test`, `make build` and `make dev` each run `script/assets`
+first, which writes the ignored `static/js/alpine.min.js` (see
+[Third-party browser assets](#third-party-browser-assets)), so
+`make test`, `make check` and the pre-commit hook work on a fresh clone
+without a separate step.

 We provide:

@@ -1236,8 +1232,8 @@ We provide:
 - `script/setup` — make a fresh clone ready for development
  (bootstrap, then install-precommit)
 - `script/projectname` — output the project name ("webhooker")
- `script/fetch-assets` — download the third-party browser assets into
-  `static/`, verifying each against its pinned sha256
+- `script/assets` — extract Alpine.js from its tarball in `3p/` (see
+  [Third-party browser assets](#third-party-browser-assets))
 - `script/test` — run the test suite
 - `script/lint` — run golangci-lint in Docker (see Linting below)
 - `script/fmt` — format all code (writes)
@@ -1259,24 +1255,25 @@ We provide:

 ## Third-party browser assets

-The web UI serves one third-party script, Alpine.js. It is **not** committed:
-a minified bundle in the tree is unreviewable, and `REPO_POLICIES.md` bars
-both committed build artifacts and unpinned external references.
+The web UI serves one third-party script, Alpine.js. Its npm package tarball
+is committed as `3p/alpinejs-3.14.9.tgz`, byte for byte as the npm registry
+publishes it. It is a dependency, not this repo's build output, so
+`REPO_POLICIES.md`'s rule against committed build artifacts does not apply.
+The directory is `3p/` rather than `vendor/` because Go treats a root
+`vendor/` directory as its module vendor directory.

-Instead `script/fetch-assets` downloads it from a pinned URL, checks the
-download against a hardcoded sha256, and installs it under `static/`. The
-sha256 of every installed asset is recorded in `static/vendor.sha256`, and
-`static/vendor_test.go` re-hashes the bytes `go:embed` put in the binary
-against that manifest — so the pin is enforced on what actually ships, not
-merely written down. Any mismatch fails the build.
+`script/assets` (`make assets`) extracts the browser build,
+`package/dist/cdn.min.js`, from the tarball to `static/js/alpine.min.js`,
+where `go:embed` picks it up. `script/test`, `make build` and `make dev` run
+it first, and the Dockerfile builds through `make test` and `make build`, so
+nothing downloads Alpine.js. The extracted file is not committed, and
+`.dockerignore` keeps any host copy out of the build context.

-`make bootstrap` runs the fetch for local development, and the Dockerfile
-runs it in the build stage; `.gitignore` and `.dockerignore` keep the
-artifact out of both the repo and the build context.
-
-To move to a new version: update the version, URL, and tarball sha256 in
-`script/fetch-assets` and the asset sha256 in `static/vendor.sha256`, then
-run `make assets && make check`.
+To move to a new version: download
+`https://registry.npmjs.org/alpinejs/-/alpinejs-<version>.tgz`, check it
+against the `dist.integrity` hash listed at
+`https://registry.npmjs.org/alpinejs/<version>`, replace the tarball in `3p/`
+with it, update its file name in `script/assets`, and run `make check`.

 ## Rationale

@@ -2695,12 +2692,16 @@ abuse limit later; they are tracked as future work.

 | Method | Path            | Description |
 | ------ | --------------- | ----------- |
-| `GET`  | `/pages/login`  | Login page (not rate limited) |
-| `POST` | `/pages/login`  | Login form submission. Credentials are verified before any limit is consulted, so a correct password is never throttled; 5 FAILED attempts per minute per bucket per submitted username, then `429`. `503` if no verification slot frees up within 5s, or immediately if 16 requests are already queued for one (see [Rate Limiting](#rate-limiting)) |
+| `GET`  | `/pages/login`  | Login page (not rate limited). Its `next` parameter names the page to return to after login; anything but a path on this site is replaced with `/` |
+| `POST` | `/pages/login`  | Login form submission. On success, redirects to the form's `next` when it is a path on this site, otherwise to `/`. Credentials are verified before any limit is consulted, so a correct password is never throttled; 5 FAILED attempts per minute per bucket per submitted username, then `429`. `503` if no verification slot frees up within 5s, or immediately if 16 requests are already queued for one (see [Rate Limiting](#rate-limiting)) |
 | `POST` | `/pages/logout` | Logout (destroys session) |

 #### Authenticated Endpoints

+A logged-out request to any of these is redirected to `/pages/login`. A
+`GET` carries its path and query there as `next`, so logging in returns
+to the page that was asked for.
+
 | Method | Path                     | Description |
 | ------ | ------------------------ | ----------- |
 | `GET`  | `/user/{username}`       | User profile page |
@@ -2755,6 +2756,8 @@ imports. The entry point is `cmd/webhooker/main.go`.

 ```
 webhooker/
+├── 3p/
+│   └── alpinejs-3.14.9.tgz    # Alpine.js npm package, extracted by make assets
 ├── cmd/webhooker/
 │   └── main.go               # Entry point: subcommand dispatch; no args locks DATA_DIR and wires fx
 ├── internal/
@@ -2848,8 +2851,7 @@ webhooker/
 │   ├── css/tailwind.css       # Generated stylesheet the pages load
 │   ├── css/style.css          # Older hand-written stylesheet, no longer loaded
 │   ├── js/app.js              # Progressive-enhancement copy-to-clipboard
-│   ├── js/alpine.min.js       # Alpine.js, fetched by script/fetch-assets, not committed
-│   └── vendor.sha256          # Pinned hashes the fetched assets are verified against
+│   └── js/alpine.min.js       # Alpine.js, extracted from 3p/ by make assets, not committed
 ├── templates/                 # Go HTML templates (base, login, sources, etc.)
 ├── script/                    # Scripts to Rule Them All entrypoints
 ├── Dockerfile                 # Three stages: lint, test+build, Alpine runtime
@@ -3161,14 +3163,14 @@ version is fixed independently of the compiler's:
   `make fmt-check`, then `golangci-lint config verify` and
   `golangci-lint run`, both with `--network=none`.
 2. **Builder stage** (`golang:1.26.1-bookworm`) — depends on the lint
-   stage passing (it copies a file from it), runs `script/fetch-assets`
-   to download and verify the third-party browser assets, then runs
-   `make test` and `make build`, and finally rebuilds the binary with
-   `CGO_ENABLED=1` and static linking so it runs on musl. Both builds
-   go through `make build`, the relink adding its `-extldflags` via
-   `GO_LDFLAGS`, so neither can drop the `-X` that stamps the version.
-   The version arrives as the `VERSION` build arg, since the context
-   has no `.git` (see [Version stamping](#version-stamping)).
+   stage passing (it copies a file from it), runs `make test` and
+   `make build` (both extract Alpine.js from `3p/` first), and finally
+   rebuilds the binary with `CGO_ENABLED=1` and static linking so it
+   runs on musl. Both builds go through `make build`, the relink adding
+   its `-extldflags` via `GO_LDFLAGS`, so neither can drop the `-X` that
+   stamps the version. The version arrives as the `VERSION` build arg,
+   since the context has no `.git` (see
+   [Version stamping](#version-stamping)).
 3. **Runtime stage** (`alpine:3.21`) — copies the static binary and
   `deploy/docker-entrypoint.sh`, creates the `/var/lib/webhooker`
   directory for all SQLite databases, exposes port 8080, and includes
@@ -79,9 +79,3 @@ func (d *Database) ExportSetBannerOut(w io.Writer) {
 func DummyPasswordHashForTest() string {
 	return dummyPasswordHash()
 }
-
-// HashPasswordWithDefaultsForTest hashes with the shipped Argon2id
-// parameters, which TestMain has lowered for HashPassword itself.
-func HashPasswordWithDefaultsForTest(password string) (string, error) {
-	return hashPasswordWith(password, DefaultPasswordConfig())
-}
@@ -1,14 +0,0 @@
-package database_test
-
-import (
-	"testing"
-
-	"sneak.berlin/go/webhooker/internal/database"
-)
-
-// TestMain lowers the password hashing cost before any test runs. See
-// database.LowerPasswordHashCostForTest.
-func TestMain(m *testing.M) {
-	database.LowerPasswordHashCostForTest()
-	m.Run()
-}
@@ -63,24 +63,10 @@ func DefaultPasswordConfig() *PasswordConfig {
 	}
 }

-// hashConfig is what HashPassword hashes with: the defaults above.
-// Only a test binary changes it, through LowerPasswordHashCostForTest,
-// before any test runs.
-//
-//nolint:gochecknoglobals // see above
-var hashConfig = DefaultPasswordConfig()
-
 // HashPassword generates an Argon2id hash of the password
 func HashPassword(password string) (string, error) {
-	return hashPasswordWith(password, hashConfig)
-}
+	config := DefaultPasswordConfig()

-// hashPasswordWith generates an Argon2id hash of the password with
-// the given parameters.
-func hashPasswordWith(
-	password string,
-	config *PasswordConfig,
-) (string, error) {
 	// Generate a salt
 	salt := make([]byte, config.SaltLen)

@@ -192,36 +192,6 @@ func TestHashPasswordUniqueness(t *testing.T) {
 	}
 }

-// TestHashPassword_ShippedParameters hashes and verifies at the
-// shipped Argon2id parameters. Every other test hashes at the lowered
-// memory cost TestMain sets, so this is the one that keeps production
-// hashing covered. One hash and one verification: each costs 64 MB.
-func TestHashPassword_ShippedParameters(t *testing.T) {
-	t.Parallel()
-
-	password := "correct horse battery staple"
-
-	hash, err := database.HashPasswordWithDefaultsForTest(password)
-	if err != nil {
-		t.Fatalf("hashing with the shipped parameters: %v", err)
-	}
-
-	const shipped = "$argon2id$v=19$m=65536,t=1,p=4$"
-
-	if !strings.HasPrefix(hash, shipped) {
-		t.Errorf("hash = %q, want prefix %q", hash, shipped)
-	}
-
-	valid, err := database.VerifyPassword(password, hash)
-	if err != nil {
-		t.Fatalf("VerifyPassword() error = %v", err)
-	}
-
-	if !valid {
-		t.Error("VerifyPassword() returned false for correct password")
-	}
-}
-
 // TestVerifyDummyPassword_DoesRealWork covers the anti-enumeration
 // path. Login charges an unknown username a verification against a
 // dummy hash so that a nonexistent account is not answered in
@@ -45,20 +45,3 @@ func NewTestWebhookDBManagerWithLogger(
 		log:     log,
 	}
 }
-
-// testArgon2Memory is the Argon2id memory cost, in KiB, that test
-// binaries hash with: 1 MB instead of the shipped 64 MB.
-const testArgon2Memory = 1024
-
-// LowerPasswordHashCostForTest makes HashPassword use a 1 MB Argon2id
-// memory cost instead of the shipped 64 MB, for the rest of the
-// process. Call it from TestMain, before any test runs.
-//
-// Every test that starts a database hashes the bootstrap admin
-// password, and a package runs dozens of those tests in parallel.
-// Under the race detector each 64 MB hash holds about 150 MB resident.
-// VerifyPassword reads the cost from the hash it checks, so
-// verification follows. Production code never calls this.
-func LowerPasswordHashCostForTest() {
-	hashConfig.Memory = testArgon2Memory
-}
@@ -1,14 +0,0 @@
-package gormlog_test
-
-import (
-	"testing"
-
-	"sneak.berlin/go/webhooker/internal/database"
-)
-
-// TestMain lowers the password hashing cost before any test runs. See
-// database.LowerPasswordHashCostForTest.
-func TestMain(m *testing.M) {
-	database.LowerPasswordHashCostForTest()
-	m.Run()
-}
@@ -2,19 +2,62 @@ package handlers

 import (
 	"net/http"
+	"net/url"
 	"strconv"
+	"strings"
+	"unicode"

 	"sneak.berlin/go/webhooker/internal/database"
 	"sneak.berlin/go/webhooker/internal/logfield"
+	"sneak.berlin/go/webhooker/internal/middleware"
 )

+// maxNextBytes bounds the page to return to after login. The login
+// page writes it into its form, and every page is rendered into a
+// buffer first (see executeTemplate), so without a bound a request
+// would choose the size of that buffer.
+const maxNextBytes = 2048
+
+// loginDestination returns where a successful login sends the
+// browser: next when it is a path on this site, otherwise "/", which
+// leads to the webhook list.
+//
+// A browser reads "//host" as another site, reads "\" as "/", and
+// drops tabs and newlines before reading at all. So the value must
+// start with exactly one "/" and hold no "\" or control character
+// anywhere: http.Redirect cleans "/a/../\host" down to "/\host". It
+// is checked after percent-decoding, so an encoded form of any of
+// these is refused too.
+func loginDestination(next string) string {
+	if len(next) > maxNextBytes {
+		return "/"
+	}
+
+	decoded, err := url.PathUnescape(next)
+	if err != nil ||
+		!strings.HasPrefix(decoded, "/") ||
+		strings.HasPrefix(decoded, "//") ||
+		strings.Contains(decoded, `\`) ||
+		strings.ContainsFunc(decoded, unicode.IsControl) {
+		return "/"
+	}
+
+	return next
+}
+
 // HandleLoginPage returns a handler for the login page (GET)
 func (h *Handlers) HandleLoginPage() http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
+		next := loginDestination(
+			r.URL.Query().Get(middleware.NextParam),
+		)
+
 		// Check if already logged in
 		sess, err := h.session.Get(r)
 		if err == nil && h.session.IsAuthenticated(sess) {
-			http.Redirect(w, r, "/", http.StatusSeeOther)
+			http.Redirect( //nolint:gosec // checked by loginDestination
+				w, r, next, http.StatusSeeOther,
+			)

 			return
 		}
@@ -22,6 +65,7 @@ func (h *Handlers) HandleLoginPage() http.HandlerFunc {
 		// Render login page
 		data := map[string]any{
 			tmplKeyError: "",
+			tmplKeyNext:  next,
 		}

 		h.renderTemplate(w, r, "login.html", data)
@@ -77,8 +121,13 @@ func (h *Handlers) HandleLoginSubmit() http.HandlerFunc {
 			"user_id", user.ID,
 		)

-		// Redirect to home page
-		http.Redirect(w, r, "/", http.StatusSeeOther)
+		// The form value is the client's to set, so it is checked
+		// again here rather than trusted from the rendered page.
+		http.Redirect( //nolint:gosec // checked by loginDestination
+			w, r,
+			loginDestination(r.PostFormValue(middleware.NextParam)),
+			http.StatusSeeOther,
+		)
 	}
 }

@@ -91,6 +140,9 @@ func (h *Handlers) renderLoginError(
 ) {
 	data := map[string]any{
 		tmplKeyError: msg,
+		tmplKeyNext: loginDestination(
+			r.PostFormValue(middleware.NextParam),
+		),
 	}

 	w.WriteHeader(status)
@@ -454,6 +454,139 @@ func TestLogin_SuccessCreatesSession(t *testing.T) {
 	)
 }

+// TestLogin_ReturnsOnlyToAPathOnThisSite is the security half of
+// https://git.eeqj.de/sneak/webhooker/issues/384: the page a login
+// returns to is client-chosen, so anything that is not a path on this
+// site, plain or percent-encoded, must land on "/", the webhook list.
+func TestLogin_ReturnsOnlyToAPathOnThisSite(t *testing.T) {
+	t.Parallel()
+
+	var (
+		h  *handlers.Handlers
+		db *database.Database
+	)
+
+	app := newTestApp(t, &h, &db)
+	app.RequireStart()
+
+	t.Cleanup(app.RequireStop)
+
+	seedOperator(t, db)
+
+	cases := []struct{ next, want string }{
+		{"/source/abc/logs?page=2", "/source/abc/logs?page=2"},
+		{"", "/"},
+		{"https://evil.example/", "/"},
+		{"https%3A%2F%2Fevil.example%2F", "/"},
+		{"//evil.example/", "/"},
+		{"%2F%2Fevil.example/", "/"},
+		{"/%2Fevil.example/", "/"},
+		{`/\evil.example/`, "/"},
+		{"%2F%5Cevil.example/", "/"},
+		{"/%5Cevil.example/", "/"},
+		{`/a/../\evil.example/`, "/"},
+		{"/\t/evil.example/", "/"},
+		{"/%09/evil.example/", "/"},
+		{"/" + strings.Repeat("a", 4096), "/"},
+	}
+
+	for _, c := range cases {
+		form := url.Values{}
+		form.Set("username", operatorUser)
+		form.Set("password", operatorPassword)
+		form.Set("next", c.next)
+
+		req := httptest.NewRequestWithContext(
+			context.Background(),
+			http.MethodPost,
+			"/pages/login",
+			strings.NewReader(form.Encode()),
+		)
+		req.Header.Set(
+			"Content-Type", "application/x-www-form-urlencoded",
+		)
+		req.RemoteAddr = sharedProxyPeer
+
+		w := httptest.NewRecorder()
+		h.HandleLoginSubmit().ServeHTTP(w, req)
+
+		assert.Equal(t, http.StatusSeeOther, w.Code, "next %q", c.next)
+		assert.Equal(
+			t, c.want, w.Header().Get("Location"), "next %q", c.next,
+		)
+	}
+}
+
+// loginPageGet renders the login page as a GET with the given next
+// value and cookies.
+func loginPageGet(
+	h *handlers.Handlers, next string, cookies []*http.Cookie,
+) *httptest.ResponseRecorder {
+	req := httptest.NewRequestWithContext(
+		context.Background(), http.MethodGet,
+		"/pages/login?"+url.Values{"next": {next}}.Encode(), nil,
+	)
+
+	for _, c := range cookies {
+		req.AddCookie(c)
+	}
+
+	w := httptest.NewRecorder()
+	h.HandleLoginPage().ServeHTTP(w, req)
+
+	return w
+}
+
+// TestLoginPage_CarriesOnlyAPathOnThisSite covers the login page
+// itself: its form carries the requested page only when it is a path
+// on this site, and a browser already logged in goes straight there.
+func TestLoginPage_CarriesOnlyAPathOnThisSite(t *testing.T) {
+	t.Parallel()
+
+	var (
+		h    *handlers.Handlers
+		sess *session.Session
+	)
+
+	app := newTestApp(t, &h, &sess)
+	app.RequireStart()
+
+	t.Cleanup(app.RequireStop)
+
+	assert.Contains(
+		t, loginPageGet(h, "/source/abc", nil).Body.String(),
+		`name="next" value="/source/abc"`,
+	)
+	assert.Contains(
+		t, loginPageGet(h, "//evil.example/", nil).Body.String(),
+		`name="next" value="/"`,
+	)
+
+	cookies := authenticatedCookies(t, sess, "test-user-id", "testuser")
+	w := loginPageGet(h, "/source/abc", cookies)
+
+	assert.Equal(t, http.StatusSeeOther, w.Code)
+	assert.Equal(t, "/source/abc", w.Header().Get("Location"))
+}
+
+// TestLoginPage_HasNoLinkToItself: the navigation bar on the login
+// page offers no link to the login page.
+func TestLoginPage_HasNoLinkToItself(t *testing.T) {
+	t.Parallel()
+
+	var h *handlers.Handlers
+
+	app := newTestApp(t, &h)
+	app.RequireStart()
+
+	t.Cleanup(app.RequireStop)
+
+	w := loginPageGet(h, "", nil)
+
+	require.Equal(t, http.StatusOK, w.Code)
+	assert.NotContains(t, w.Body.String(), `href="/pages/login"`)
+}
+
 // TestLogin_UsernameAtLimitCanLogIn shows that a username of exactly
 // database.MaxUsernameBytes still fits in the session cookie. Past
 // what the cookie can carry, a correct login answers 500.
@@ -36,6 +36,9 @@ const (
 	tmplKeyError = "Error"
 	// tmplKeyWebhook is the template data key for a webhook.
 	tmplKeyWebhook = "Webhook"
+	// tmplKeyNext is the template data key for the page to return
+	// to after login.
+	tmplKeyNext = "Next"
 )

 // errInvalidPassword is returned when a password does not match.
@@ -1,14 +0,0 @@
-package handlers_test
-
-import (
-	"testing"
-
-	"sneak.berlin/go/webhooker/internal/database"
-)
-
-// TestMain lowers the password hashing cost before any test runs. See
-// database.LowerPasswordHashCostForTest.
-func TestMain(m *testing.M) {
-	database.LowerPasswordHashCostForTest()
-	m.Run()
-}
@@ -158,7 +158,10 @@ func TestUserRoute_Unauthenticated_RedirectedByMiddleware(t *testing.T) {
 		"handler must not be reached for unauthenticated request",
 	)
 	assert.Equal(t, http.StatusSeeOther, w.Code)
-	assert.Equal(t, "/pages/login", w.Header().Get("Location"))
+	assert.Equal(
+		t, "/pages/login?next=%2Fuser%2Ftestuser",
+		w.Header().Get("Location"),
+	)
 }

 // passwordChangeRequest builds a POST request to the password-change
@@ -6,6 +6,7 @@ import (
 	"log/slog"
 	"net"
 	"net/http"
+	"net/url"
 	"sync"
 	"time"

@@ -366,6 +367,24 @@ func (s *Middleware) CORS() func(http.Handler) http.Handler {
 	}
 }

+// NextParam is the query parameter on the login redirect, and the
+// login form field, that holds the page to return to after login.
+const NextParam = "next"
+
+// loginURL is the login page RequireAuth redirects to. A GET carries
+// its own path and query in NextParam so that logging in returns to
+// it; HandleLoginSubmit decides whether that value is safe to follow.
+// Other methods carry nothing, since a redirect cannot repeat them.
+func loginURL(r *http.Request) string {
+	if r.Method != http.MethodGet {
+		return "/pages/login"
+	}
+
+	return "/pages/login?" + url.Values{
+		NextParam: {r.URL.RequestURI()},
+	}.Encode()
+}
+
 // RequireAuth returns middleware that checks for a valid session.
 // Unauthenticated users are redirected to the login page.
 func (s *Middleware) RequireAuth() func(http.Handler) http.Handler {
@@ -381,7 +400,7 @@ func (s *Middleware) RequireAuth() func(http.Handler) http.Handler {
 					"error", err,
 				)
 				http.Redirect(
-					w, r, "/pages/login", http.StatusSeeOther,
+					w, r, loginURL(r), http.StatusSeeOther,
 				)

 				return
@@ -409,7 +428,7 @@ func (s *Middleware) RequireAuth() func(http.Handler) http.Handler {
 					),
 				)
 				http.Redirect(
-					w, r, "/pages/login", http.StatusSeeOther,
+					w, r, loginURL(r), http.StatusSeeOther,
 				)

 				return
@@ -338,6 +338,42 @@ func TestRequireAuth_NoSession_RedirectsToLogin(t *testing.T) {
 			"unauthenticated request",
 	)
 	assert.Equal(t, http.StatusSeeOther, w.Code)
+	assert.Equal(
+		t, "/pages/login?next=%2Fdashboard", w.Header().Get("Location"),
+	)
+}
+
+// TestRequireAuth_LoginRedirectCarriesOnlyAGet pins what the login
+// redirect carries: a GET's path and query, so logging in can return
+// there, and nothing for a POST, which a redirect cannot repeat.
+func TestRequireAuth_LoginRedirectCarriesOnlyAGet(t *testing.T) {
+	t.Parallel()
+
+	m, _ := testMiddleware(t, config.EnvironmentDev)
+
+	handler := m.RequireAuth()(http.HandlerFunc(
+		func(_ http.ResponseWriter, _ *http.Request) {},
+	))
+
+	get := httptest.NewRequestWithContext(
+		context.Background(),
+		http.MethodGet, "/source/abc/logs?page=2", nil,
+	)
+	w := httptest.NewRecorder()
+	handler.ServeHTTP(w, get)
+
+	assert.Equal(
+		t, "/pages/login?next=%2Fsource%2Fabc%2Flogs%3Fpage%3D2",
+		w.Header().Get("Location"),
+	)
+
+	post := httptest.NewRequestWithContext(
+		context.Background(),
+		http.MethodPost, "/source/abc/delete", nil,
+	)
+	w = httptest.NewRecorder()
+	handler.ServeHTTP(w, post)
+
 	assert.Equal(t, "/pages/login", w.Header().Get("Location"))
 }

@@ -443,7 +479,9 @@ func TestRequireAuth_UnauthenticatedSession_RedirectsToLogin(
 			"unauthenticated session",
 	)
 	assert.Equal(t, http.StatusSeeOther, w.Code)
-	assert.Equal(t, "/pages/login", w.Header().Get("Location"))
+	assert.Equal(
+		t, "/pages/login?next=%2Fdashboard", w.Header().Get("Location"),
+	)
 }

 // --- RequireAuth Session Expiry Tests ---
@@ -541,7 +579,9 @@ func TestRequireAuth_IdleExpiredSession_RedirectsToLogin(
 		"handler should not run for an idle-expired session",
 	)
 	assert.Equal(t, http.StatusSeeOther, w.Code)
-	assert.Equal(t, "/pages/login", w.Header().Get("Location"))
+	assert.Equal(
+		t, "/pages/login?next=%2Fdashboard", w.Header().Get("Location"),
+	)
 	assert.Empty(
 		t, sessionCookies(w),
 		"an expired session must not be refreshed",
@@ -1,14 +0,0 @@
-package resetpw_test
-
-import (
-	"testing"
-
-	"sneak.berlin/go/webhooker/internal/database"
-)
-
-// TestMain lowers the password hashing cost before any test runs. See
-// database.LowerPasswordHashCostForTest.
-func TestMain(m *testing.M) {
-	database.LowerPasswordHashCostForTest()
-	m.Run()
-}
@@ -140,7 +140,7 @@ func (n *noopEvictor) EvictWebhook(string) {}
 // and the database, exactly as internal/handlers builds them.
 //
 // One application per test function, not per case: every start that
-// finds no account seeds one with an Argon2id hash, and this package's
+// finds no account seeds one at 64 MB of Argon2id, and this package's
 // budget is not the place to spend that repeatedly.
 func newServerApp(
 	t *testing.T, dir string,
@@ -1,14 +0,0 @@
-package server_test
-
-import (
-	"testing"
-
-	"sneak.berlin/go/webhooker/internal/database"
-)
-
-// TestMain lowers the password hashing cost before any test runs. See
-// database.LowerPasswordHashCostForTest.
-func TestMain(m *testing.M) {
-	database.LowerPasswordHashCostForTest()
-	m.Run()
-}
@@ -680,6 +680,44 @@ func TestPagesLogin_CookiesFromAnEarlierDatabase(t *testing.T) {
 	)
 }

+// TestPagesLogin_ReturnsToTheRequestedPage is
+// https://git.eeqj.de/sneak/webhooker/issues/384: a page opened while
+// logged out leads to the login page, and logging in from there lands
+// on that page, query included.
+func TestPagesLogin_ReturnsToTheRequestedPage(t *testing.T) {
+	t.Parallel()
+
+	const (
+		username = "operator"
+		password = "correct-horse-battery-staple"
+	)
+
+	env := newTestEnv(t)
+	userID, _ := env.seedUser(t, username, password)
+	asked := "/source/" + env.seedWebhook(t, userID).ID + "/logs?page=2"
+
+	bounced := env.get(asked, nil)
+	require.Equal(t, http.StatusSeeOther, bounced.Code)
+
+	loginPage := bounced.Header().Get("Location")
+
+	match := regexp.MustCompile(`name="next" value="([^"]*)"`).
+		FindStringSubmatch(env.get(loginPage, nil).Body.String())
+	require.Len(t, match, 2, "the login form must carry the page")
+
+	token, cookies := env.csrfFrom(t, loginPage, nil)
+
+	form := url.Values{}
+	form.Set("csrf_token", token)
+	form.Set("username", username)
+	form.Set("password", password)
+	form.Set("next", html.UnescapeString(match[1]))
+
+	w := env.post("/pages/login", form, cookies)
+	require.Equal(t, http.StatusSeeOther, w.Code)
+	assert.Equal(t, asked, w.Header().Get("Location"))
+}
+
 // --- /user/{username} group ---

 // TestPasswordChange_OversizeBody_RejectedAndPasswordUnchanged
@@ -830,7 +868,10 @@ func TestSourceLogsBody_OtherUser404s(t *testing.T) {

 	anon := env.get(path, nil)
 	assert.Equal(t, http.StatusSeeOther, anon.Code)
-	assert.Equal(t, "/pages/login", anon.Header().Get("Location"))
+	assert.Equal(
+		t, "/pages/login?next="+url.QueryEscape(path),
+		anon.Header().Get("Location"),
+	)
 }

 // TestDeliveryReplay_PostOnlyAndCSRFProtected walks the replay action
@@ -13,9 +13,9 @@ import (

 // TestBaseTemplateScriptsAreServed walks every /s/ script the base
 // template loads on each page and fetches it through the real router.
-// Alpine.js is fetched at build time rather than committed, so nothing
-// in the repo guarantees it is present: this is the check that the page
-// still gets the JavaScript it asks for.
+// Alpine.js is extracted from its tarball in 3p/ at build time, so the
+// file is not in the tree: this is the check that the page still gets
+// the JavaScript it asks for.
 func TestBaseTemplateScriptsAreServed(t *testing.T) {
 	t.Parallel()

@@ -0,0 +1,16 @@
+#!/bin/sh
+# script/assets: extract Alpine.js from its npm package tarball, committed
+# in 3p/, to static/js/alpine.min.js, where go:embed reads it. The
+# extracted file is not committed. script/test, make build and make dev run
+# this first.
+set -eu
+
+ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
+
+main() {
+    cd "$ROOT"
+    tar -xzOf 3p/alpinejs-3.14.9.tgz package/dist/cdn.min.js \
+        >static/js/alpine.min.js
+}
+
+main "$@"
@@ -4,9 +4,7 @@
 # installed tools are skipped. Base tooling comes from nix, apt, brew,
 # or apk (detected in that order); assumes NOTHING is present (not git,
 # make, or go). golangci-lint is deliberately not installed: linting runs
-# only in docker, via script/lint and Dockerfile.lint. Finishes by running
-# script/fetch-assets, which installs the hash-pinned third-party browser
-# assets the repo does not commit.
+# only in docker, via script/lint and Dockerfile.lint.
 set -eu

 ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
@@ -69,11 +67,6 @@ main() {

    go mod download

-    # Third-party browser assets are not committed; fetch and verify them
-    # so a fresh clone can build and test.
-    if missing curl; then pkg_install curl curl curl curl; fi
-    "$ROOT/script/fetch-assets"
-
    echo "bootstrap complete"
 }

@@ -1,6 +1,7 @@
 #!/bin/sh
 # script/check: run all checks (test, lint, fmt-check). Our own
-# extension to scripts-to-rule-them-all. Must not modify any files.
+# extension to scripts-to-rule-them-all.
+# Writes only the ignored static/js/alpine.min.js, through script/test.
 # Generic: usually needs no adaptation.
 set -eu

@@ -1,104 +0,0 @@
-#!/bin/sh
-# script/fetch-assets: download the third-party browser assets the web UI
-# ships and install them under static/. Minified bundles are not committed
-# (REPO_POLICIES.md: no build artifacts in version control), so the build
-# fetches them here. Every download is verified against a hardcoded sha256
-# before it is installed, and any mismatch aborts. Idempotent: an asset
-# already present with its pinned hash is left alone.
-set -eu
-
-ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
-
-# The sha256 of each installed asset lives in static/vendor.sha256, in
-# sha256sum(1) format, with paths relative to static/. That file is the
-# single source of truth: this script verifies against it, and
-# static/vendor_test.go asserts the bytes embedded into the binary match
-# it, so the hash cannot rot into a value nothing checks.
-MANIFEST="static/vendor.sha256"
-
-# Alpine.js 3.14.9, 2026-08-17. Fetched from registry.npmjs.org, the
-# publisher of record; the jsDelivr and unpkg copies are mirrors of this
-# same tarball. dist/cdn.min.js is the browser build Alpine publishes for
-# a <script> tag.
-ALPINE_VERSION="3.14.9"
-ALPINE_URL="https://registry.npmjs.org/alpinejs/-/alpinejs-${ALPINE_VERSION}.tgz"
-# sha256 of alpinejs-3.14.9.tgz
-ALPINE_TARBALL_SHA256="97dad7c0c81e659cfc8e7700055da9770f8186187cb9a8a76efb57e00d5ce52a"
-ALPINE_MEMBER="package/dist/cdn.min.js"
-ALPINE_DEST="js/alpine.min.js"
-
-sha256_of() {
-    if command -v sha256sum >/dev/null 2>&1; then
-        sha256sum "$1" | cut -d' ' -f1
-    else
-        shasum -a 256 "$1" | cut -d' ' -f1
-    fi
-}
-
-# expected_sha256 <path-relative-to-static>
-expected_sha256() {
-    awk -v want="$1" '$2 == want { print $1; found = 1 }
-        END { if (!found) exit 1 }' "$ROOT/$MANIFEST"
-}
-
-# verify <file> <expected-sha256> <what>
-verify() {
-    actual="$(sha256_of "$1")"
-    if [ "$actual" != "$2" ]; then
-        echo "fetch-assets: sha256 mismatch for $3" >&2
-        echo "  expected: $2" >&2
-        echo "  actual:   $actual" >&2
-        exit 1
-    fi
-}
-
-# up_to_date <path-relative-to-static> <expected-sha256>
-up_to_date() {
-    [ -f "$ROOT/static/$1" ] || return 1
-    [ "$(sha256_of "$ROOT/static/$1")" = "$2" ]
-}
-
-fetch_alpine() {
-    want="$(expected_sha256 "$ALPINE_DEST")"
-
-    if up_to_date "$ALPINE_DEST" "$want"; then
-        echo "fetch-assets: static/$ALPINE_DEST already at $want"
-        return 0
-    fi
-
-    echo "fetch-assets: fetching Alpine.js $ALPINE_VERSION from $ALPINE_URL"
-    tmp="$(mktemp -d)"
-    trap 'rm -rf "$tmp"' EXIT INT TERM
-    curl -fsSL -o "$tmp/alpine.tgz" "$ALPINE_URL"
-    verify "$tmp/alpine.tgz" "$ALPINE_TARBALL_SHA256" "alpinejs-${ALPINE_VERSION}.tgz"
-    tar -xzOf "$tmp/alpine.tgz" "$ALPINE_MEMBER" >"$tmp/alpine.min.js"
-    verify "$tmp/alpine.min.js" "$want" "$ALPINE_MEMBER from alpinejs-${ALPINE_VERSION}.tgz"
-
-    mkdir -p "$(dirname "$ROOT/static/$ALPINE_DEST")"
-    cp "$tmp/alpine.min.js" "$ROOT/static/$ALPINE_DEST"
-    rm -rf "$tmp"
-    trap - EXIT INT TERM
-    echo "fetch-assets: installed static/$ALPINE_DEST ($want)"
-}
-
-# Re-check every manifest entry against what is now on disk, so an entry
-# no script installs fails loudly instead of passing silently.
-verify_manifest() {
-    while read -r want path; do
-        case "$want" in '' | '#'*) continue ;; esac
-        if [ ! -f "$ROOT/static/$path" ]; then
-            echo "fetch-assets: $MANIFEST lists static/$path, which is missing" >&2
-            exit 1
-        fi
-        verify "$ROOT/static/$path" "$want" "static/$path"
-    done <"$ROOT/$MANIFEST"
-}
-
-main() {
-    cd "$ROOT"
-    fetch_alpine
-    verify_manifest
-    echo "fetch-assets: all assets in $MANIFEST verified"
-}
-
-main "$@"
@@ -22,18 +22,14 @@
 # The one figure above 90s is GOMAXPROCS 1, a synthetic core floor rather than
 # a condition CI runs under. If a CPU-limited runner ever puts a real run near
 # 67s, that is the datum to revisit the org figure with.
-#
-# -p 4 -parallel 8 keep the run under 2 GB of memory: at most four test
-# binaries build or run at once, each with at most eight parallel tests. Under
-# -race every test binary and every link costs a few hundred MB, so the
-# defaults (one per core) add up to several GB on a many-core host.
 set -eu

 ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"

 main() {
    cd "$ROOT"
-    go test -v -race -p 4 -parallel 8 -timeout 90s ./...
+    "$ROOT/script/assets"
+    go test -v -race -timeout 90s ./...
 }

 main "$@"
@@ -1 +0,0 @@
-3ed1eed252488921df65e363d6715deb04d7f92aaedb9e52199fdf73cb1e0ad3  js/alpine.min.js
@@ -1,92 +0,0 @@
-package static_test
-
-import (
-	"bufio"
-	"crypto/sha256"
-	"encoding/hex"
-	"os"
-	"strings"
-	"testing"
-
-	"github.com/stretchr/testify/require"
-
-	"sneak.berlin/go/webhooker/static"
-)
-
-const manifestPath = "vendor.sha256"
-
-// fetchHint is appended to every failure here: the assets the manifest
-// covers are fetched by the build, not committed, so a fresh clone that
-// has not run script/fetch-assets fails this test and should be told why.
-const fetchHint = "run `script/fetch-assets` (or `make assets`) to install " +
-	"the pinned third-party assets"
-
-// TestVendoredAssetsMatchManifest asserts that every asset listed in
-// static/vendor.sha256 is embedded in the binary with exactly the pinned
-// bytes. script/fetch-assets verifies the same hashes at download time;
-// this test verifies them again on what actually ships, so a build that
-// skipped, cached, or subverted the fetch cannot produce a binary serving
-// unpinned third-party JavaScript.
-func TestVendoredAssetsMatchManifest(t *testing.T) {
-	t.Parallel()
-
-	entries := readManifest(t)
-	require.NotEmpty(t, entries, "%s lists no assets", manifestPath)
-
-	for path, want := range entries {
-		t.Run(path, func(t *testing.T) {
-			t.Parallel()
-
-			data, err := static.Static.ReadFile(path)
-			require.NoErrorf(
-				t, err,
-				"%s is listed in %s but is not embedded; %s",
-				path, manifestPath, fetchHint,
-			)
-
-			sum := sha256.Sum256(data)
-			got := hex.EncodeToString(sum[:])
-			require.Equalf(
-				t, want, got,
-				"embedded %s does not match its pinned sha256 in %s; %s",
-				path, manifestPath, fetchHint,
-			)
-		})
-	}
-}
-
-// readManifest parses static/vendor.sha256, which is in sha256sum(1)
-// format with paths relative to static/.
-func readManifest(t *testing.T) map[string]string {
-	t.Helper()
-
-	f, err := os.Open(manifestPath)
-	require.NoError(t, err, "opening %s", manifestPath)
-
-	defer func() { require.NoError(t, f.Close()) }()
-
-	entries := make(map[string]string)
-	scanner := bufio.NewScanner(f)
-
-	for scanner.Scan() {
-		line := strings.TrimSpace(scanner.Text())
-		if line == "" || strings.HasPrefix(line, "#") {
-			continue
-		}
-
-		fields := strings.Fields(line)
-		require.Lenf(
-			t, fields, 2,
-			"%s: malformed entry %q, want \"<sha256>  <path>\"",
-			manifestPath, line,
-		)
-
-		sum, path := fields[0], fields[1]
-		require.Lenf(t, sum, 64, "%s: %q is not a sha256", manifestPath, sum)
-		entries[path] = sum
-	}
-
-	require.NoError(t, scanner.Err(), "reading %s", manifestPath)
-
-	return entries
-}
@@ -24,6 +24,7 @@

            <form method="POST" action="/pages/login" class="space-y-6">
                <input type="hidden" name="csrf_token" value="{{.CSRFToken}}">
+                <input type="hidden" name="next" value="{{.Next}}">
                <div class="form-group">
                    <label for="username" class="label">Username</label>
                    <input
@@ -6,12 +6,14 @@
        </div>

        <!-- Mobile menu button -->
+        {{if .User}}
        <button @click="open = !open" class="md:hidden p-2 rounded-md text-gray-500 hover:bg-gray-100">
            <svg class="w-6 h-6" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                <path x-show="!open" stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M4 6h16M4 12h16M4 18h16"/>
                <path x-show="open" x-cloak stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M6 18L18 6M6 6l12 12"/>
            </svg>
        </button>
+        {{end}}

        <!-- Desktop navigation -->
        <div class="hidden md:flex items-center gap-4">
@@ -28,8 +30,6 @@
                <input type="hidden" name="csrf_token" value="{{.CSRFToken}}">
                <button type="submit" class="btn-text">Logout</button>
            </form>
-            {{else}}
-            <a href="/pages/login" class="btn-primary">Login</a>
            {{end}}
        </div>
    </div>
@@ -44,8 +44,6 @@
                <input type="hidden" name="csrf_token" value="{{.CSRFToken}}">
                <button type="submit" class="btn-text w-full text-left">Logout</button>
            </form>
-            {{else}}
-            <a href="/pages/login" class="btn-primary w-full">Login</a>
            {{end}}
        </div>
    </div>
				`@@ -1 +0,0 @@`
				`3ed1eed252488921df65e363d6715deb04d7f92aaedb9e52199fdf73cb1e0ad3 js/alpine.min.js`