State what the default blocklist covers (closes #244)

The default blocklist covers the IPv4 private and reserved ranges, IPv6
loopback, unique local and link-local addresses, and public addresses
that hand credentials, user data or bootstrap material to whatever can
reach them, without the caller presenting anything. A provider's other
public addresses, such as 161.26.0.0/16 and 166.8.0.0/14, are not
refused: they hand out no credentials that way, reaching them can be
legitimate, and every cloud has some, so a partial list would promise
coverage it does not give.

The README's egress section and the comment above blockedNetworks now
state this rule, naming the same material as the rule above
alwaysBlockedNetworks, so nobody infers wider coverage and a future
candidate can be accepted or refused against it. No list change.

Model: opus-5-5

README.md

@@ -145,11 +145,6 @@ TTY detection, and security headers are always applied.
 | `TRUSTED_PROXIES`       | CIDRs whose forwarded headers are trusted (unset: all clients behind a proxy share one rate-limit bucket; a correct login password is never throttled either way) | `""` (none) |
 | `ALLOWED_EGRESS_CIDRS`  | CIDRs that delivery targets may reach despite the SSRF blocklist. Read [Allowing egress to your own network](#allowing-egress-to-your-own-network) before setting it | `""` (none) |
 
-The Settings page of the web UI (`/settings`, behind the login) lists
-every one of these with the value the running server loaded. It is
-read-only, and it shows `METRICS_PASSWORD` and `SENTRY_DSN` only as
-set or not set, never their values.
-
 #### Allowing egress to your own network
 
 By default every delivery target must resolve to a public address. The
@@ -162,6 +157,21 @@ public cloud metadata addresses: currently only `168.63.129.16`, Azure's
 WireServer, which serves an Azure VM its credentials. Because it is a
 public address, listing it in `ALLOWED_EGRESS_CIDRS` reopens it.
 
+That is all the default blocklist covers: the IPv4 private and reserved
+ranges; of IPv6, only loopback (`::1`), unique local addresses
+(`fc00::/7`) and link-local addresses (`fe80::/10`); and certain public
+addresses. A public address belongs on the default blocklist only if it
+hands credentials, user data or bootstrap material to whatever can reach
+it, without the caller presenting anything. A provider's other public
+addresses are not refused. IBM Cloud, for example, serves its package
+mirrors, time servers and object storage on `161.26.0.0/16`, and the
+private endpoints of its own cloud services on `166.8.0.0/14`. Neither
+range hands out credentials that way: the token service among those
+endpoints issues a token only in exchange for something the caller
+presents, such as an API key. Reaching these services can be a
+legitimate delivery, and every cloud has some, so a partial list would
+promise coverage it does not give.
+
 That default is also inconvenient for the thing webhooker is mostly
 for: taking a public webhook and forwarding it to something on your own
 network. A container on the same Docker network, a box on `10.x`, a
@@ -2707,7 +2717,6 @@ abuse limit later; they are tracked as future work.
 | ------ | ------------------------ | ----------- |
 | `GET`  | `/user/{username}`       | User profile page |
 | `POST` | `/user/{username}/password` | Change the user's password (5 per minute per bucket, then `429`; `503` if no verification slot frees up within 5s, or immediately if 16 requests are already queued for one) |
-| `GET`  | `/settings`              | Read-only list of the configuration the server is running with; `METRICS_PASSWORD` and `SENTRY_DSN` show only as set or not set |
 | `GET`  | `/sources`               | List user's webhooks |
 | `GET`  | `/sources/new`           | Create webhook form |
 | `POST` | `/sources/new`           | Create webhook submission |
@@ -2820,7 +2829,6 @@ webhooker/
 │   │   ├── healthcheck.go     # Health check handler
 │   │   ├── index.go           # Index page handler
 │   │   ├── profile.go         # User profile handler
-│   │   ├── settings.go        # Read-only Settings page handler
 │   │   ├── source_management.go  # Webhook CRUD handlers
 │   │   └── webhook.go         # Webhook receiver handler
 │   ├── healthcheck/

internal/delivery/ssrf.go

@@ -43,6 +43,13 @@ var (
 // permit specific blocks out of this set with
 // ALLOWED_EGRESS_CIDRS; see Guard.
 //
+// A public address belongs on the default blocklist only if it
+// hands credentials, user data or bootstrap material to whatever
+// can reach it, without the caller presenting anything. A
+// provider's other public addresses are not refused, since
+// reaching them can be legitimate and no list of them could be
+// complete.
+//
 //nolint:gochecknoglobals // package-level network list is appropriate here
 var blockedNetworks []*net.IPNet
 

internal/handlers/handlers.go

@@ -13,7 +13,6 @@ import (
 	"sync/atomic"
 
 	"go.uber.org/fx"
-	"sneak.berlin/go/webhooker/internal/config"
 	"sneak.berlin/go/webhooker/internal/database"
 	"sneak.berlin/go/webhooker/internal/delivery"
 	"sneak.berlin/go/webhooker/internal/globals"
@@ -54,7 +53,6 @@ type HandlersParams struct {
 
 	Logger       *logger.Logger
 	Globals      *globals.Globals
-	Config       *config.Config
 	Database     *database.Database
 	WebhookDBMgr *database.WebhookDBManager
 	Healthcheck  *healthcheck.Healthcheck
@@ -131,7 +129,6 @@ func New(
 	s.templates = map[string]*template.Template{
 		"login.html":         parsePageTemplate("login.html"),
 		"profile.html":       parsePageTemplate("profile.html"),
-		"settings.html":      parsePageTemplate("settings.html"),
 		"sources_list.html":  parsePageTemplate("sources_list.html"),
 		"sources_new.html":   parsePageTemplate("sources_new.html"),
 		"source_detail.html": parsePageTemplate("source_detail.html"),

internal/handlers/handlers_test.go

@@ -83,25 +83,16 @@ func newTestApp(
 ) *fxtest.App {
 	t.Helper()
 
-	return newTestAppWithConfig(
-		t, &config.Config{DataDir: t.TempDir()}, targets...,
-	)
-}
-
-// newTestAppWithConfig is newTestApp over a caller-supplied Config.
-func newTestAppWithConfig(
-	t *testing.T,
-	cfg *config.Config,
-	targets ...any,
-) *fxtest.App {
-	t.Helper()
-
 	return fxtest.New(
 		t,
 		fx.Provide(
 			globals.New,
 			logger.New,
-			func() *config.Config { return cfg },
+			func() *config.Config {
+				return &config.Config{
+					DataDir: t.TempDir(),
+				}
+			},
 			database.New,
 			database.NewWebhookDBManager,
 			healthcheck.New,

internal/handlers/profile_test.go

@@ -88,6 +88,8 @@ func TestHandleProfile_OwnProfile_OK(t *testing.T) {
 	h.HandleProfile().ServeHTTP(w, req)
 
 	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Contains(t, w.Body.String(), "Account Information")
+	assert.NotContains(t, w.Body.String(), "Account Type")
 }
 
 func TestHandleProfile_OtherProfile_Forbidden(t *testing.T) {

internal/handlers/settings.go

@@ -1,130 +0,0 @@
-package handlers
-
-import (
-	"net/http"
-	"net/netip"
-	"strconv"
-	"strings"
-
-	"sneak.berlin/go/webhooker/internal/config"
-)
-
-// notSet is what the Settings page shows for a value that is empty.
-const notSet = "not set"
-
-// settingRow is one line of the Settings page: an environment
-// variable, what it controls, and the value the server loaded for it.
-type settingRow struct {
-	Name        string
-	Description string
-	Value       string
-}
-
-// HandleSettings returns a handler for the read-only Settings page,
-// which lists the configuration the server started with.
-func (h *Handlers) HandleSettings() http.HandlerFunc {
-	return func(w http.ResponseWriter, r *http.Request) {
-		h.renderTemplate(w, r, "settings.html", map[string]any{
-			"Settings": settingRows(h.params.Config),
-		})
-	}
-}
-
-// settingRows lists every field of cfg under the environment variable
-// it is read from, in the order of the README's configuration table.
-// METRICS_PASSWORD and SENTRY_DSN are credentials, so their values
-// never reach the page: only whether they are set.
-func settingRows(cfg *config.Config) []settingRow {
-	metricsUsername := cfg.MetricsUsername
-	if metricsUsername == "" {
-		metricsUsername = notSet
-	}
-
-	return []settingRow{
-		{"WEBHOOKER_ENVIRONMENT", "dev or prod", cfg.Environment},
-		{"PORT", "HTTP listen port", strconv.Itoa(cfg.Port)},
-		{
-			"BIND_ADDRESS",
-			"IP address the HTTP listener binds",
-			cfg.BindAddress,
-		},
-		{
-			"DATA_DIR",
-			"Directory for all SQLite databases",
-			cfg.DataDir,
-		},
-		{
-			"DEBUG",
-			"Enable debug logging",
-			strconv.FormatBool(cfg.Debug),
-		},
-		{
-			"MAINTENANCE_MODE",
-			"Report maintenanceMode: true in the healthcheck JSON. " +
-				"It does not change how any request is served",
-			strconv.FormatBool(cfg.MaintenanceMode),
-		},
-		{
-			"METRICS_USERNAME",
-			"Basic auth username for /metrics",
-			metricsUsername,
-		},
-		{
-			"METRICS_PASSWORD",
-			"Basic auth password for /metrics",
-			setOrNotSet(cfg.MetricsPassword),
-		},
-		{
-			"SENTRY_DSN",
-			"Error reporting DSN. Unset leaves error reporting off",
-			setOrNotSet(cfg.SentryDSN),
-		},
-		{
-			"RETENTION_SWEEP_INTERVAL",
-			"How often the retention reaper and archive sweeper run",
-			cfg.RetentionSweepInterval.String(),
-		},
-		{
-			"SESSION_IDLE_TIMEOUT",
-			"Idle session timeout. Zero or negative disables idle " +
-				"expiry",
-			cfg.SessionIdleTimeout.String(),
-		},
-		{
-			"RECEIVER_RATE_LIMIT",
-			"Receiver requests per minute per IP per entrypoint " +
-				"(10x that per IP across the route)",
-			strconv.Itoa(cfg.ReceiverRateLimit),
-		},
-		{
-			"TRUSTED_PROXIES",
-			"CIDRs whose forwarded headers are trusted",
-			cidrList(cfg.TrustedProxies),
-		},
-		{
-			"ALLOWED_EGRESS_CIDRS",
-			"CIDRs that delivery targets may reach despite the " +
-				"SSRF blocklist",
-			cidrList(cfg.AllowedEgressCIDRs),
-		},
-	}
-}
-
-// setOrNotSet is how the Settings page shows a credential: whether it
-// has a value, never the value itself.
-func setOrNotSet(value string) string {
-	if value == "" {
-		return notSet
-	}
-
-	return "set"
-}
-
-// cidrList renders a CIDR list setting for the Settings page.
-func cidrList(prefixes []netip.Prefix) string {
-	if len(prefixes) == 0 {
-		return "none"
-	}
-
-	return strings.Join(config.PrefixStrings(prefixes), ", ")
-}

internal/handlers/settings_test.go

@@ -1,130 +0,0 @@
-package handlers_test
-
-import (
-	"context"
-	"html"
-	"net/http"
-	"net/http/httptest"
-	"net/netip"
-	"regexp"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-	"sneak.berlin/go/webhooker/internal/config"
-	"sneak.berlin/go/webhooker/internal/handlers"
-	"sneak.berlin/go/webhooker/internal/session"
-)
-
-// settingsShown renders the Settings page over cfg as a logged-in user
-// and returns the value it shows for each variable name, plus the
-// whole page.
-func settingsShown(
-	t *testing.T, cfg *config.Config,
-) (map[string]string, string) {
-	t.Helper()
-
-	var h *handlers.Handlers
-
-	var sess *session.Session
-
-	app := newTestAppWithConfig(t, cfg, &h, &sess)
-	app.RequireStart()
-
-	t.Cleanup(app.RequireStop)
-
-	req := httptest.NewRequestWithContext(
-		context.Background(), http.MethodGet, "/settings", nil,
-	)
-	for _, c := range authenticatedCookies(t, sess, "id", "admin") {
-		req.AddCookie(c)
-	}
-
-	w := httptest.NewRecorder()
-	h.HandleSettings().ServeHTTP(w, req)
-	require.Equal(t, http.StatusOK, w.Code)
-
-	body := w.Body.String()
-
-	row := regexp.MustCompile(
-		`<code[^>]*>([A-Z_]+)</code>\s*<code[^>]*>([^<]*)</code>`,
-	)
-
-	shown := map[string]string{}
-	for _, match := range row.FindAllStringSubmatch(body, -1) {
-		shown[match[1]] = html.UnescapeString(match[2])
-	}
-
-	return shown, body
-}
-
-func TestSettingsPageShowsLoadedConfiguration(t *testing.T) {
-	t.Parallel()
-
-	const (
-		metricsPassword = "metrics-password-1f9a"
-		sentryKey       = "dsnkey7c2e"
-		sentryDSN       = "https://" + sentryKey + "@errors.example.com/42"
-	)
-
-	cfg := &config.Config{
-		DataDir:                t.TempDir(),
-		Debug:                  true,
-		MaintenanceMode:        true,
-		Environment:            config.EnvironmentDev,
-		MetricsUsername:        "scraper",
-		MetricsPassword:        metricsPassword,
-		Port:                   9123,
-		SentryDSN:              sentryDSN,
-		BindAddress:            "192.0.2.10",
-		RetentionSweepInterval: 17 * time.Minute,
-		SessionIdleTimeout:     3 * time.Hour,
-		ReceiverRateLimit:      77,
-		TrustedProxies: []netip.Prefix{
-			netip.MustParsePrefix("10.1.0.0/16"),
-		},
-		AllowedEgressCIDRs: []netip.Prefix{
-			netip.MustParsePrefix("192.168.5.0/24"),
-			netip.MustParsePrefix("fd00::/8"),
-		},
-	}
-
-	shown, body := settingsShown(t, cfg)
-
-	assert.Equal(t, map[string]string{
-		"WEBHOOKER_ENVIRONMENT":    "dev",
-		"PORT":                     "9123",
-		"BIND_ADDRESS":             "192.0.2.10",
-		"DATA_DIR":                 cfg.DataDir,
-		"DEBUG":                    "true",
-		"MAINTENANCE_MODE":         "true",
-		"METRICS_USERNAME":         "scraper",
-		"METRICS_PASSWORD":         "set",
-		"SENTRY_DSN":               "set",
-		"RETENTION_SWEEP_INTERVAL": "17m0s",
-		"SESSION_IDLE_TIMEOUT":     "3h0m0s",
-		"RECEIVER_RATE_LIMIT":      "77",
-		"TRUSTED_PROXIES":          "10.1.0.0/16",
-		"ALLOWED_EGRESS_CIDRS":     "192.168.5.0/24, fd00::/8",
-	}, shown)
-
-	assert.NotContains(t, body, metricsPassword)
-	assert.NotContains(t, body, sentryKey)
-	assert.Contains(
-		t, body, `href="/settings"`,
-		"the navigation bar links to the page",
-	)
-}
-
-func TestSettingsPageShowsUnsetValues(t *testing.T) {
-	t.Parallel()
-
-	shown, _ := settingsShown(t, &config.Config{DataDir: t.TempDir()})
-
-	assert.Equal(t, "not set", shown["METRICS_USERNAME"])
-	assert.Equal(t, "not set", shown["METRICS_PASSWORD"])
-	assert.Equal(t, "not set", shown["SENTRY_DSN"])
-	assert.Equal(t, "none", shown["TRUSTED_PROXIES"])
-	assert.Equal(t, "none", shown["ALLOWED_EGRESS_CIDRS"])
-}

internal/server/routes.go

@@ -141,7 +141,6 @@ func (s *Server) setupRoutes() {
 
 	s.setupPageRoutes()
 	s.setupUserRoutes()
-	s.setupSettingsRoutes()
 	s.setupSourceRoutes()
 	s.setupWebhookRoutes()
 }
@@ -182,21 +181,6 @@ func (s *Server) setupUserRoutes() {
 	})
 }
 
-// setupSettingsRoutes serves the Settings page. It is GET only:
-// configuration comes from the environment and nothing here changes
-// it.
-func (s *Server) setupSettingsRoutes() {
-	s.router.Route("/settings", func(r chi.Router) {
-		// MaxBodySize precedes CSRF and RequireAuth deliberately;
-		// see maxFormBodySize for why, and for what it costs.
-		r.Use(s.mw.MaxBodySize(maxFormBodySize))
-		r.Use(s.mw.CSRF())
-		r.Use(s.mw.NoCache())
-		r.Use(s.mw.RequireAuth())
-		r.Get("/", s.h.HandleSettings())
-	})
-}
-
 func (s *Server) setupSourceRoutes() {
 	s.router.Route("/sources", func(r chi.Router) {
 		// MaxBodySize precedes CSRF and RequireAuth deliberately;

internal/server/settings_test.go

@@ -1,22 +0,0 @@
-package server_test
-
-import (
-	"net/http"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-)
-
-func TestSettingsPageIsBehindLogin(t *testing.T) {
-	t.Parallel()
-
-	env := newTestEnv(t)
-
-	w := env.get("/settings", nil)
-	assert.Equal(t, http.StatusSeeOther, w.Code)
-	assert.Equal(t, "/pages/login", w.Header().Get("Location"))
-
-	w = env.get("/settings", env.authCookies(t, "id", "admin"))
-	assert.Equal(t, http.StatusOK, w.Code)
-	assert.Contains(t, w.Body.String(), "WEBHOOKER_ENVIRONMENT")
-}

templates/navbar.html

@@ -17,7 +17,6 @@
         <div class="hidden md:flex items-center gap-4">
             {{if .User}}
             <a href="/sources" class="btn-text">Webhooks</a>
-            <a href="/settings" class="btn-text">Settings</a>
             <a href="/user/{{.User.Username}}" class="btn-text">
                 <svg class="w-5 h-5 mr-1" fill="currentColor" viewBox="0 0 16 16">
                     <path d="M11 6a3 3 0 1 1-6 0 3 3 0 0 1 6 0z"/>
@@ -40,7 +39,6 @@
         <div class="flex flex-col gap-2">
             {{if .User}}
             <a href="/sources" class="btn-text w-full text-left">Webhooks</a>
-            <a href="/settings" class="btn-text w-full text-left">Settings</a>
             <a href="/user/{{.User.Username}}" class="btn-text w-full text-left">Profile</a>
             <form method="POST" action="/pages/logout">
                 <input type="hidden" name="csrf_token" value="{{.CSRFToken}}">

templates/profile.html

@@ -41,10 +41,6 @@
                     <dt class="w-32 text-sm font-medium text-gray-500">Username</dt>
                     <dd class="text-sm text-gray-900">{{.User.Username}}</dd>
                 </div>
-                <div class="flex">
-                    <dt class="w-32 text-sm font-medium text-gray-500">Account Type</dt>
-                    <dd class="text-sm text-gray-900">Standard User</dd>
-                </div>
             </dl>
         </div>
     </div>

templates/settings.html

@@ -1,24 +0,0 @@
-{{template "base" .}}
-
-{{define "title"}}Settings - Webhooker{{end}}
-
-{{define "content"}}
-<div class="max-w-6xl mx-auto px-6 py-8">
-    <h1 class="text-2xl font-medium text-gray-900">Settings</h1>
-    <p class="text-sm text-gray-500 mt-1 mb-6">The configuration this server started with. It is set in the server's environment and cannot be changed here.</p>
-
-    <div class="card">
-        <div class="divide-y divide-gray-100">
-            {{range .Settings}}
-            <div class="p-4">
-                <div class="flex justify-between items-start gap-4">
-                    <code class="text-sm font-medium text-gray-900">{{.Name}}</code>
-                    <code class="text-sm text-gray-900 break-all">{{.Value}}</code>
-                </div>
-                <p class="text-sm text-gray-500 mt-1">{{.Description}}</p>
-            </div>
-            {{end}}
-        </div>
-    </div>
-</div>
-{{end}}