Send Content-Type once on a delivery (closes #246)

A delivery set Content-Type from the event's ContentType and then
added the inbound Content-Type from the event's stored headers, so
the target could receive two values. The inbound Content-Type is no
longer forwarded from the stored headers; the receiver already saved
it as the event's ContentType.

Which value wins is now stated at applyRequestHeaders: a Content-Type
configured on the target, otherwise the event's ContentType,
otherwise none.

Model: opus-5-5

README.md

@@ -147,7 +147,7 @@ TTY detection, and security headers are always applied.
 | `RETENTION_SWEEP_INTERVAL` | How often the retention reaper and archive sweeper run (Go duration, must be positive) | `1h` |
 | `SESSION_IDLE_TIMEOUT`  | Idle session timeout (Go duration)  | `24h`    |
 | `RECEIVER_RATE_LIMIT`   | Receiver requests/minute per IP per entrypoint (10x that per IP across the route) | `120` |
-| `TRUSTED_PROXIES`       | CIDRs whose forwarded headers are trusted. A set value replaces the default. Under the default, any client with a private address, whether it connects directly or through the proxy, can choose its own rate-limit key by sending its own `X-Forwarded-For`; if any clients have private addresses, set it to the proxy's address alone. See [Trusted proxies](#trusted-proxies) | `10.0.0.0/8,172.16.0.0/12,192.168.0.0/16` (RFC 1918) |
+| `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) |
 
 #### Allowing egress to your own network
@@ -157,11 +157,6 @@ private and reserved ranges — RFC 1918, loopback, CGNAT, link-local and
 the rest — are refused, which stops a target from being used to make
 webhooker probe the network it sits in.
 
-Besides the private and reserved ranges, the default blocklist refuses
-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 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
@@ -200,16 +195,15 @@ Two things this setting cannot do:
   the list is always an allowlist; an empty list (the default) means
   every private and reserved range stays refused. Note that
   `0.0.0.0/0` gets you most of the way there anyway, per above.
-- **It cannot open link-local, or a cloud metadata endpoint at a
-  non-public address that discloses credentials or user data.** An
-  address is on the list below when it is not a public address and both
-  of these hold: the provider fixes it, so it cannot collide with
-  anything you run; and reaching it hands out credentials, user data or
-  bootstrap material. Those stay blocked no matter what you list,
-  including when you list them outright or list a supernet such as
-  `0.0.0.0/0`, `::/0`, `fd00::/8` or `100.64.0.0/10`. Treat this as best
-  effort rather than a guarantee — it is a hand-maintained list and the
-  caveat below the table applies:
+- **It cannot open link-local, or a cloud metadata endpoint that
+  discloses credentials or user data.** An address is on the list below
+  when both of these hold: the provider fixes it, so it cannot collide
+  with anything you run; and reaching it hands out credentials, user
+  data or bootstrap material. Those stay blocked no matter what you
+  list, including when you list them outright or list a supernet such
+  as `0.0.0.0/0`, `::/0`, `fd00::/8` or `100.64.0.0/10`. Treat this as
+  best effort rather than a guarantee — it is a hand-maintained list
+  and the caveat below the table applies:
 
   | Blocked unconditionally | What it is |
   | ----------------------- | ---------- |
@@ -248,8 +242,7 @@ Two things this setting cannot do:
   encodings, which the default blocklist does not match. A publicly
   routable metadata address is not listed here, because nothing on this
   list can be reopened and blocking one that way would leave you no
-  escape hatch at all; Azure's `168.63.129.16` is refused by the default
-  blocklist instead, as described above.
+  escape hatch at all.
 
   This list is not exhaustive of every cloud's metadata address — if
   yours is not here, do not allowlist the block that contains it.
@@ -379,48 +372,41 @@ unlocked.
 `TRUSTED_PROXIES` is a comma-separated list of CIDR blocks (a bare
 address such as `192.168.1.7` is accepted and treated as a single
 host), for example `192.168.1.7, 2001:db8::5`. It decides whose
-`X-Forwarded-For` header the rate limiters believe, so it should cover
-the addresses of your reverse proxies.
+`X-Forwarded-For` header the rate limiters believe, so it should name
+the addresses of your reverse proxies and nothing else.
 
 `X-Forwarded-For` is honoured **only** when the connecting peer is
 inside one of these blocks; for every other peer the client identity is
-the connection's own address and the header is ignored. Unset (or
-empty), the list is the RFC 1918 private ranges: `10.0.0.0/8`,
-`172.16.0.0/12` and `192.168.0.0/16`. That covers a reverse proxy
-reaching webhooker over a Docker network or a private LAN without
-anything set. A set value replaces the default entirely. A set but
-unparseable value aborts startup.
+the connection's own address and the header is ignored. The default is
+the empty list, which trusts nobody — anything else would let any
+client pick its own rate limit bucket, minting a fresh one per request
+or draining someone else's. Set it to the address of your reverse
+proxy, and to nothing wider. A set but unparseable value aborts
+startup.
 
-Trusting those ranges has two consequences for clients with private
-addresses:
-
-- Any such client, whether it connects directly or through the proxy,
-  can choose its own rate-limit key by sending its own
-  `X-Forwarded-For`. A direct client's header is walked because the
-  client is itself trusted; behind the proxy, the client's own address
-  is skipped as a trusted hop when the chain is walked (below), so the
-  entry it wrote is taken as the client. If any of your clients have
-  private addresses, you must set `TRUSTED_PROXIES` to the proxy's
-  address alone.
-- A client behind the proxy that sends no `X-Forwarded-For` of its own
-  shares the proxy's bucket, because its own address is skipped too.
-  Setting the list to the proxy's address alone gives each its own
-  bucket.
-
-A proxy the list does not cover, such as nginx on the same host
-reaching webhooker over loopback, is not trusted: every request through
-it keys on the proxy's own address and all clients share a single
+That default is safe against forged headers, but leaving it unset in
+production has a cost you must know about. Production runs behind a
+TLS-terminating reverse proxy, so with `TRUSTED_PROXIES` unset every
+request keys on the proxy's own address and all clients share a single
 bucket per limit. The receiver limits become service-wide ceilings,
 and the login endpoint's failure counting collapses onto one key, so a
 stranger's wrong passwords throttle every other client's wrong
-passwords. Set `TRUSTED_PROXIES` to that proxy's address to restore
-per-client buckets.
+passwords.
 
 What it cannot do is lock the operator out. The login endpoint
 verifies credentials **before** it consults any limit and charges only
 failures, so a correct password is never throttled no matter how full
 the bucket is. See [Rate Limiting](#rate-limiting).
 
+The remedy is to set `TRUSTED_PROXIES` to your reverse proxy's
+address, which restores per-client buckets. webhooker logs a warning
+at startup whenever `TRUSTED_PROXIES` is empty, in every environment,
+because behind a proxy every client shares one bucket in `dev` and
+`prod` alike. The warning is informational when nothing proxies to the
+process: with no proxy in front, the peer address is the client's own
+and the buckets are already per-client. See
+[Rate Limiting](#rate-limiting) for what each limit shares.
+
 `X-Real-IP` and `True-Client-IP` are **never** read, from any peer.
 Reverse proxies append to `X-Forwarded-For` but forward other client
 headers verbatim, so a single-valued header is client-controlled even
@@ -442,14 +428,14 @@ Two operator requirements follow:
   (nginx `$proxy_add_x_forwarded_for`, HAProxy `option forwardfor`,
   Caddy and AWS ALB by default), and must append a bare address with
   no port.
-- Keep clients out of the list. Any address inside `TRUSTED_PROXIES`
+- List proxy hosts **only**. Any address inside `TRUSTED_PROXIES`
   chooses its own rate-limit key: its `X-Forwarded-For` is walked, so
   it can name a different address on every request to get a fresh
   bucket each time, or name another client's address to drain that
-  client's bucket. A block that also covers clients — the default, on
-  a network where clients have private addresses — makes all three
-  limits, including the unauthenticated webhook receiver, silently
-  bypassable by every client in the block.
+  client's bucket. Never list a block that also covers clients — a
+  broad `10.0.0.0/8` on a network where clients live in the same range
+  makes all three limits, including the unauthenticated webhook
+  receiver, silently bypassable by every client in the block.
 
 #### Sessions
 
@@ -771,16 +757,10 @@ repository's `Dockerfile` and runs it. The app needs:
 
 - **Environment variables:**
     - `WEBHOOKER_ENVIRONMENT=prod`
-    - `TRUSTED_PROXIES`: Docker networks use private addresses, so the
-      default covers your reverse proxy on that network. Under the
-      default, any client with a private address, whether it connects
-      directly or through the proxy, can choose its own rate-limit key
-      by sending its own `X-Forwarded-For`. If any clients have private
-      addresses, or the network's addresses are outside the RFC 1918
-      ranges, set it to the proxy's address there. The `remoteIP` field
-      of the `http request` log line for a request that came through
-      the proxy shows it; the health check's own lines show `::1`. See
-      [Trusted proxies](#trusted-proxies).
+    - `TRUSTED_PROXIES`: your reverse proxy's address on that Docker
+      network. The `remoteIP` field of the `http request` log line for a
+      request that came through the proxy shows it; the health check's
+      own lines show `::1`. See [Trusted proxies](#trusted-proxies).
     - Leave `BIND_ADDRESS` and `DATA_DIR` unset: the image sets
       `BIND_ADDRESS` to `0.0.0.0`, and `DATA_DIR` defaults to
       `/var/lib/webhooker`.
@@ -843,14 +823,12 @@ reports.
    behind a proxy means the `X-Forwarded-Proto` header. The block below
    sets it; without it every request is read as plaintext and cookies
    ship without `Secure`. See [Configuration](#configuration).
-3. **Make sure `TRUSTED_PROXIES` covers the proxy's address.** Unset,
-   it covers the RFC 1918 private ranges, so a proxy on a Docker
-   network or a private LAN is covered and one on loopback is not. For
-   a proxy it does not cover, every rate limiter keys on the connecting
-   peer, which is the proxy on every request: all clients collapse into
-   one global bucket per limit and the receiver's per-IP limits become
-   service-wide ceilings. See [Trusted proxies](#trusted-proxies). If
-   any clients have private addresses, list the proxy and nothing else.
+3. **Set `TRUSTED_PROXIES` to the proxy's address.** Unset, every rate
+   limiter keys on the connecting peer, which behind a proxy is the
+   proxy on every request: all clients collapse into one global bucket
+   per limit and the receiver's per-IP limits become service-wide
+   ceilings. See [Trusted proxies](#trusted-proxies). List the proxy
+   and nothing else.
 4. **Send `Host` as `$http_host`, not `$host`.** `$host` strips the
    port. webhooker's Origin/Referer check compares against the host it
    was given, so on any port other than 443 `$host` makes every form
@@ -990,10 +968,15 @@ scratch file**: it holds committed transactions that are not yet in the
 have no readable schema at all. `-shm` is regenerable, but there is no
 reason to separate the two — copy the directory and you have them.
 
-A clean shutdown closes every database, which checkpoints and removes
-its sidecars; a killed or crashed instance leaves them, and they must be
-carried with the `.db`. An archive the service has not opened since a
-crash keeps that crash's sidecars, even across a later clean stop.
+A clean shutdown closes `webhooker.db` and every `events-*.db`, which
+checkpoints and removes their sidecars; a killed or crashed instance
+leaves them, and they must be carried with the `.db`. **Archive
+databases are different**: their handle is not closed at shutdown, so
+`archive-*.db-wal` and `-shm` normally survive a clean stop and the
+`-wal` can hold every row the archive has. Measured on a stopped
+instance: `archive-….db` 4096 bytes with no table, its `-wal` 157 KB
+holding all 8 archived events. Copying `DATA_DIR` in full is what makes
+this a non-issue; copying `.db` files out of it by name is not.
 
 Configuration is **not** in `DATA_DIR` — it comes from the environment
 and from a `.env` file read out of the process working directory. Back
@@ -1068,9 +1051,10 @@ The file becomes self-contained again when the handle closes, which
 happens on the next write past the debounce window, when the connection
 pool retires the idle connection (about a minute after the last write),
 or at the idle archive sweep — measured, the same file was a complete
-20 KB `.db` with no sidecars about a minute after its last write. A
-clean stop closes it too. So either move `archive-{uuid}.db` together
-with any `-wal`/`-shm` beside it, or wait until there are none.
+20 KB `.db` with no sidecars about a minute after its last write.
+Shutdown is **not** on that list: the archive handle is not closed when
+the service stops. So either move `archive-{uuid}.db` together with any
+`-wal`/`-shm` beside it, or wait until there are none.
 
 ### Restore
 
@@ -1089,10 +1073,12 @@ with any `-wal`/`-shm` beside it, or wait until there are none.
    They are part of the database, and dropping a `-wal` silently
    discards every transaction it still holds. An `.backup` set will not
    contain any: it writes a single consolidated file per database. A
-   stop-and-copy set normally has none, because a clean stop closes
-   every database and checkpoints its sidecars away; the exception is an
-   archive not opened since a crash. A copy salvaged from a crashed
-   instance has them for everything, and needs all of them.
+   stop-and-copy set has none for `webhooker.db` or the `events-*.db`,
+   because a clean stop closes those and checkpoints their sidecars
+   away — but it will normally have them for `archive-*.db`, whose
+   handle stays open across shutdown, and those carry the archive's
+   rows. A copy salvaged from a crashed instance has them for
+   everything, and needs all of them.
 
 4. **Fix ownership.** The container runs as the non-root `webhooker`
    user, UID 1000 / GID 1000. Restored files must be owned by (or
@@ -1411,11 +1397,10 @@ It uses:
 - **[go-chi/httprate](https://github.com/go-chi/httprate)** for
   sliding-window rate limiting of the password-change and webhook
   receiver endpoints. The bucket is per client IP only when
-  `TRUSTED_PROXIES` covers the reverse proxy (by default it covers the
-  RFC 1918 private ranges); otherwise every client behind that proxy
-  shares one bucket per limit. The login endpoint counts failed
-  attempts itself instead, so that a correct password is never
-  throttled (see [Rate Limiting](#rate-limiting))
+  `TRUSTED_PROXIES` names the reverse proxy; unset, every client
+  behind that proxy shares one bucket per limit. The login endpoint
+  counts failed attempts itself instead, so that a correct password is
+  never throttled (see [Rate Limiting](#rate-limiting))
 - **[Prometheus](https://prometheus.io)** for metrics, served at
   `/metrics` behind basic auth
 - **[Sentry](https://sentry.io)** for optional error reporting
@@ -2596,30 +2581,30 @@ let one subscriber rotate source addresses and mint a fresh bucket per
 request, evading these limits at the network layer without spoofing
 anything; the cost is that distinct clients inside one `/64` share a
 bucket. IPv4-mapped addresses (`::ffff:1.2.3.4`) key as the IPv4 address
-they carry. See [Trusted proxies](#trusted-proxies). When that variable
-does not cover the reverse proxy, a client behind it shares one bucket
-with every other client behind the same proxy. Set `TRUSTED_PROXIES` to
-the proxy's address to get per-client limits back. What the shared bucket
+they carry. See [Trusted proxies](#trusted-proxies). Deployed without that
+variable set, a client behind a reverse proxy shares one bucket with
+every other client behind the same proxy. Set `TRUSTED_PROXIES` to the
+proxy's address to get per-client limits back. What the shared bucket
 costs is not the same for every limiter, and the two cases pull in
 opposite directions:
 
 - For the **receiver** limits it costs throughput, which is the safe
   direction to be wrong in: sharing can only make a limit bind sooner,
   never let a sender past it. It matters more for the aggregate limit
-  than for the per-entrypoint one: when `TRUSTED_PROXIES` does not
-  cover the reverse proxy a production deployment is required to run
-  behind, every request keys on the proxy, so the aggregate limit
-  becomes a service-wide ceiling of 1200 requests per minute across all
-  senders and all entrypoints, where the per-entrypoint limit's
-  capacity still grows with the number of entrypoints. Any deployment
-  with more than a handful of busy entrypoints must make sure
-  `TRUSTED_PROXIES` covers its proxy.
+  than for the per-entrypoint one: with `TRUSTED_PROXIES` unset behind
+  the reverse proxy a production deployment is required to run behind,
+  every request keys on the proxy, so the aggregate limit becomes a
+  service-wide ceiling of 1200 requests per minute across all senders
+  and all entrypoints, where the per-entrypoint limit's capacity still
+  grows with the number of entrypoints. Any deployment with more than a
+  handful of busy entrypoints must set `TRUSTED_PROXIES`.
 - For the **login and password-change** limits it costs precision, not
   availability. Login failures from every client land in one counter,
   so a stranger's wrong passwords make the operator's own wrong
   passwords answer `429` sooner; the operator's _correct_ password is
   never affected, because it is never counted. Production deployments
-  should still make sure `TRUSTED_PROXIES` covers their proxy.
+  should still set `TRUSTED_PROXIES`; webhooker warns at startup
+  whenever it is empty, in any environment.
 
 #### The login endpoint
 
@@ -2722,10 +2707,8 @@ re-fills both verification slots on its first two requests. The
 remedies are to block the source at the reverse proxy, or to
 rate-limit `POST /pages/login` there — the one place a limit can be
 applied without reintroducing the lockout, because the proxy sees the
-real client address. `TRUSTED_PROXIES` does not stop the saturation.
-The flood's source is in the proxy's access log: webhooker's own logs
-record the proxy's address, not the client's (see
-[Deployment behind a reverse proxy](#deployment-behind-a-reverse-proxy)).
+real client address. Setting `TRUSTED_PROXIES` does not stop the
+saturation, but it makes the source visible in the failure logs.
 
 Finer-grained per-webhook rate limits (configured in the web UI and
 enforced in the webhook handler) can layer on top of this env-level
@@ -3082,9 +3065,10 @@ check, see [The login endpoint](#the-login-endpoint).
   It runs behind session auth, so only a client already holding a
   valid session reaches it, and an operator throttled out of changing
   a password can still log in. The bucket is per client IP only when
-  `TRUSTED_PROXIES` covers the reverse proxy; otherwise every client
+  `TRUSTED_PROXIES` names the reverse proxy; unset, every client
   shares one bucket, which costs precision rather than availability
-  (see [Rate Limiting](#rate-limiting))
+  (see [Rate Limiting](#rate-limiting)). webhooker warns at startup
+  whenever `TRUSTED_PROXIES` is empty
 - Prometheus metrics behind basic auth
 - Static assets embedded in binary (no filesystem access needed at
   runtime)
@@ -3104,8 +3088,7 @@ each hook. The order, read off the fx stop-hook log:
 3. `server` — the HTTP drain, bounded separately by
    `server.ShutdownTimeout` (**3 seconds**), then a Sentry flush if
    `SENTRY_DSN` is set
-4. `delivery.Engine` — waits for its workers, then closes the archive
-   databases
+4. `delivery.Engine`
 5. `healthcheck`
 6. `WebhookDBManager`
 7. the database close

internal/config/config.go

@@ -75,11 +75,6 @@ const (
 	// internet-exposed endpoint.
 	defaultReceiverRateLimit = 120
 
-	// defaultTrustedProxies is TRUSTED_PROXIES when it is unset: the
-	// RFC 1918 private ranges, which a reverse proxy reaching the
-	// process over a Docker network or a private LAN connects from.
-	defaultTrustedProxies = "10.0.0.0/8,172.16.0.0/12,192.168.0.0/16"
-
 	// maxPort is the highest valid TCP port number. The lower
 	// bound (at least 1) is enforced by envPositiveInt.
 	maxPort = 65535
@@ -177,14 +172,13 @@ type Config struct {
 
 	// TrustedProxies is the set of networks whose members are
 	// allowed to speak for the client with X-Forwarded-For, the
-	// only forwarded header read. Unless TRUSTED_PROXIES is set it
-	// is the RFC 1918 private ranges (defaultTrustedProxies).
-	// Other peers' forwarded headers are ignored and they are
-	// identified by the connection's own address. Under the
-	// default any client with a private address, directly or
-	// through a proxy, can choose its own rate-limit key, so
-	// where any clients have private addresses this must be set
-	// to the proxy hosts alone.
+	// only forwarded header read. It is empty unless
+	// TRUSTED_PROXIES is set, and empty means no peer is
+	// trusted: forwarded headers are then ignored entirely and
+	// clients are identified by the connection's own address.
+	// Members can choose their own rate-limit key, so this must
+	// name proxy hosts only, never a block that also covers
+	// clients.
 	TrustedProxies []netip.Prefix
 
 	// AllowedEgressCIDRs is the set of networks a delivery target
@@ -198,10 +192,9 @@ type Config struct {
 	// alwaysBlockedNetworks stays blocked no matter what is listed
 	// here. That set is link-local plus the cloud metadata
 	// endpoints outside it that disclose credentials or user data
-	// at a provider-fixed, non-public address; it is not
-	// exhaustive of every cloud's metadata address. See
-	// alwaysBlockedNetworks for the authoritative list and the
-	// criterion it is built from.
+	// at a provider-fixed address; it is not exhaustive of every
+	// cloud's metadata address. See alwaysBlockedNetworks for the
+	// authoritative list and the criterion it is built from.
 	AllowedEgressCIDRs []netip.Prefix
 
 	params *ConfigParams
@@ -466,15 +459,14 @@ func parseCIDR(entry string) (netip.Prefix, error) {
 
 // envPrefixList returns the value of the named environment variable
 // parsed as a comma-separated list of CIDR blocks (bare addresses
-// allowed). An unset, empty, or blank value is read as defaultValue
-// instead. A set value containing an unparseable entry is a hard
-// error naming the key and the bad entry, so startup fails loudly
-// rather than silently running with a list the operator did not
-// intend.
-func envPrefixList(key, defaultValue string) ([]netip.Prefix, error) {
+// allowed). An unset, empty, or blank value yields an empty list. A
+// set value containing an unparseable entry is a hard error naming
+// the key and the bad entry, so startup fails loudly rather than
+// silently running with a list the operator did not intend.
+func envPrefixList(key string) ([]netip.Prefix, error) {
 	v := strings.TrimSpace(os.Getenv(key))
 	if v == "" {
-		v = defaultValue
+		return nil, nil
 	}
 
 	var prefixes []netip.Prefix
@@ -688,12 +680,12 @@ func loadFromEnv() (*Config, error) {
 		return nil, err
 	}
 
-	trustedProxies, err := envPrefixList("TRUSTED_PROXIES", defaultTrustedProxies)
+	trustedProxies, err := envPrefixList("TRUSTED_PROXIES")
 	if err != nil {
 		return nil, err
 	}
 
-	allowedEgressCIDRs, err := envPrefixList("ALLOWED_EGRESS_CIDRS", "")
+	allowedEgressCIDRs, err := envPrefixList("ALLOWED_EGRESS_CIDRS")
 	if err != nil {
 		return nil, err
 	}
@@ -754,19 +746,61 @@ func (c *Config) warnEgressAllowlist(log *slog.Logger) {
 
 	log.Warn(
 		"ALLOWED_EGRESS_CIDRS lets delivery targets reach these "+
-			"otherwise-blocked networks. Anyone who can create a "+
-			"delivery target can now make this process issue "+
-			"requests into them, and read back the response. Only "+
-			"the addresses the README lists as blocked "+
-			"unconditionally stay blocked regardless of what is "+
-			"listed here; a public cloud metadata address such as "+
-			"168.63.129.16 is reachable once it, or a block "+
-			"covering it, is listed.",
+			"otherwise-blocked private/reserved networks. Anyone "+
+			"who can create a delivery target can now make this "+
+			"process issue requests into them, and read back the "+
+			"response. Link-local and the known cloud instance "+
+			"metadata endpoints outside it stay blocked "+
+			"regardless of what is listed here.",
 		"allowedEgressCIDRs",
 		strings.Join(PrefixStrings(c.AllowedEgressCIDRs), ","),
 	)
 }
 
+// warnSharedRateLimitBucket logs a startup warning whenever
+// TRUSTED_PROXIES is empty, in any environment.
+//
+// With no trusted proxies every rate limiter keys on the connecting
+// peer's address. Whether that is harmless or dangerous depends on
+// what is in front of the process, which this code cannot observe:
+// with nothing in front, the peer is the client and the limits are
+// per-client as intended; behind a reverse proxy the peer is the proxy
+// for every request, so all clients share one bucket per limiter.
+//
+// The login endpoint no longer spends budget on arrival — it verifies
+// credentials first and charges only failures — so a shared bucket
+// cannot deny the operator a correct password. What it does collapse
+// is the failure counting: one client's wrong passwords throttle
+// everyone else's wrong passwords, and the receiver's limits become
+// service-wide ceilings.
+//
+// The warning is deliberately not gated on WEBHOOKER_ENVIRONMENT:
+// behind a proxy every client shares one bucket in dev and prod alike.
+//
+// The default of trusting nobody is deliberate — trusting forwarded
+// headers from arbitrary peers lets any client choose its own bucket —
+// so this warns rather than failing startup or changing the key.
+func (c *Config) warnSharedRateLimitBucket(log *slog.Logger) {
+	if len(c.TrustedProxies) > 0 {
+		return
+	}
+
+	log.Warn(
+		"TRUSTED_PROXIES is empty: every rate limit keys on the "+
+			"connecting peer's address. With nothing proxying to "+
+			"this process that is the client itself and the limits "+
+			"are per-client as intended. Behind a reverse proxy the "+
+			"peer is the proxy on every request, so all clients "+
+			"share one bucket per limit: the receiver limits become "+
+			"service-wide ceilings, and one client's failed logins "+
+			"throttle every other client's failed logins — a "+
+			"correct password still gets in. If anything proxies to "+
+			"this process, set TRUSTED_PROXIES to its address.",
+		"environment", c.Environment,
+		"trustedProxies", len(c.TrustedProxies),
+	)
+}
+
 // New creates a Config by reading environment variables.
 //
 //nolint:revive // lc parameter is required by fx even if unused.
@@ -812,6 +846,7 @@ func New(lc fx.Lifecycle, params ConfigParams) (*Config, error) {
 		"hasMetricsAuth", s.MetricsAuthEnabled(),
 	)
 
+	s.warnSharedRateLimitBucket(log)
 	s.warnEgressAllowlist(log)
 
 	return s, nil

internal/config/config_test.go

@@ -551,11 +551,6 @@ func testReceiverRateLimitSuccess(
 }
 
 func TestTrustedProxies(t *testing.T) {
-	// Unset, the RFC 1918 private ranges are trusted, so a reverse
-	// proxy on a Docker network or a private LAN is covered without
-	// configuration.
-	defaultProxies := []string{cidrPrivateV4, "172.16.0.0/12", "192.168.0.0/16"}
-
 	tests := []struct {
 		name        string
 		set         bool
@@ -564,21 +559,18 @@ func TestTrustedProxies(t *testing.T) {
 		expected    []string
 	}{
 		{
+			// The default must be "trust nobody": an empty list
+			// means forwarded headers are ignored, never that
+			// every peer may speak for the client.
 			name:     caseUnsetUsesDefault,
 			set:      false,
-			expected: defaultProxies,
+			expected: []string{},
 		},
 		{
-			name:     "blank value uses default",
+			name:     "blank value trusts nothing",
 			set:      true,
 			value:    "  ",
-			expected: defaultProxies,
-		},
-		{
-			name:     "set value replaces the default entirely",
-			set:      true,
-			value:    "203.0.113.7",
-			expected: []string{"203.0.113.7/32"},
+			expected: []string{},
 		},
 		{
 			name:  caseValidValueParsed,
@@ -842,13 +834,107 @@ func TestEgressAllowlistWarning(t *testing.T) {
 			// to be able to read back which networks are open.
 			assert.Contains(t, logged, "10.0.0.0/8")
 			assert.Contains(t, logged, "127.0.0.0/8")
-			// What stays shut is the whole unconditional set, not
-			// link-local alone; a public metadata address is not in
-			// it, so a listed block covering it opens it.
-			assert.Contains(t, logged, "blocked unconditionally")
-			assert.Contains(t, logged, "168.63.129.16 is reachable")
-			// The listed blocks need not be private or reserved.
-			assert.NotContains(t, logged, "private/reserved")
+			// What stays shut. Asserted on the clause naming the
+			// wider set rather than on "Link-local" alone, so the
+			// string cannot narrow back to link-local only while
+			// the always-blocked set covers ULA, CGNAT and two
+			// public metadata addresses as well.
+			assert.Contains(t, logged, "metadata endpoints outside it")
+		})
+	}
+}
+
+// TestSharedRateLimitBucketWarning covers the startup warning that
+// tells an operator a deployment behind a reverse proxy shares one
+// rate-limit bucket between every client, which turns the receiver
+// limits into service-wide ceilings and collapses login failure
+// counting. It must fire whenever TRUSTED_PROXIES is empty, in any
+// environment, because behind a proxy every client shares one bucket
+// in dev and prod alike. It stays quiet once proxies are named.
+func TestSharedRateLimitBucketWarning(t *testing.T) {
+	tests := []struct {
+		name           string
+		environment    string
+		trustedProxies string
+		expectWarning  bool
+	}{
+		{
+			name:          "prod without trusted proxies warns",
+			environment:   config.EnvironmentProd,
+			expectWarning: true,
+		},
+		{
+			name:           "prod with trusted proxies is quiet",
+			environment:    config.EnvironmentProd,
+			trustedProxies: cidrPrivateV4,
+			expectWarning:  false,
+		},
+		{
+			name:          "dev without trusted proxies warns",
+			environment:   config.EnvironmentDev,
+			expectWarning: true,
+		},
+		{
+			name:           "dev with trusted proxies is quiet",
+			environment:    config.EnvironmentDev,
+			trustedProxies: cidrPrivateV4,
+			expectWarning:  false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			// Cannot use t.Parallel() here because t.Setenv
+			// is incompatible with parallel subtests.
+			t.Setenv("WEBHOOKER_ENVIRONMENT", tt.environment)
+
+			if tt.trustedProxies == "" {
+				require.NoError(
+					t, os.Unsetenv("TRUSTED_PROXIES"),
+				)
+			} else {
+				t.Setenv("TRUSTED_PROXIES", tt.trustedProxies)
+			}
+
+			var buf bytes.Buffer
+
+			log := slog.New(slog.NewJSONHandler(
+				&buf, &slog.HandlerOptions{
+					Level: slog.LevelDebug,
+				},
+			))
+
+			require.NoError(
+				t,
+				config.WarnSharedRateLimitBucketForTest(log),
+			)
+
+			if !tt.expectWarning {
+				assert.Empty(t, buf.String())
+
+				return
+			}
+
+			logged := buf.String()
+
+			assert.Contains(t, logged, `"level":"WARN"`)
+			assert.Contains(t, logged, "TRUSTED_PROXIES")
+			assert.Contains(t, logged, "share one bucket")
+			assert.Contains(
+				t, logged, "throttle every other client's failed logins",
+			)
+			// The warning must not claim a lockout the login
+			// endpoint no longer permits: credentials are verified
+			// before any budget is spent.
+			assert.Contains(
+				t, logged, "a correct password still gets in",
+			)
+			// The text must stay accurate for a developer with
+			// nothing in front of the process, where an empty
+			// list costs nothing.
+			assert.Contains(
+				t, logged, "nothing proxying to this process",
+			)
 		})
 	}
 }

internal/config/export_test.go

@@ -6,6 +6,21 @@ import "log/slog"
 // the external config_test package so each helper can be covered by
 // its own table-driven test without weakening the package API.
 
+// WarnSharedRateLimitBucketForTest loads a Config from the current
+// environment and emits its startup warnings to log. The real logger
+// writes to stdout, so this lets the warning's firing condition be
+// asserted against a handler the test controls.
+func WarnSharedRateLimitBucketForTest(log *slog.Logger) error {
+	c, err := loadFromEnv()
+	if err != nil {
+		return err
+	}
+
+	c.warnSharedRateLimitBucket(log)
+
+	return nil
+}
+
 // WarnEgressAllowlistForTest loads a Config from the current
 // environment and emits its egress-allowlist startup warning to
 // log, so a test can assert both that the warning fires only when

internal/delivery/engine.go

@@ -362,15 +362,6 @@ func (e *Engine) start() {
 // stop cancels the worker pool's context and waits for the pool
 // to drain, bounded by the stop hook's context: a wedged worker
 // must not hang the process past fx's stop timeout.
-//
-// Once the pool has drained it closes the archive writers, so a
-// clean stop leaves no archive -wal behind. Nothing else holds a
-// writer for long by then: the archive sweeper stops before the
-// engine, and deleting a webhook only closes one. If the pool did
-// not drain in time, the writers are left open, as a kill would
-// leave them. Closing them would wait for any write in progress,
-// and a worker still running would then open new writers that
-// nothing closes, so it gains nothing over a kill.
 func (e *Engine) stop(ctx context.Context) error {
 	e.log.Info("delivery engine stopping")
 
@@ -385,8 +376,6 @@ func (e *Engine) stop(ctx context.Context) error {
 		return err
 	}
 
-	e.dbTarget.evictAll()
-
 	e.log.Info("delivery engine stopped")
 
 	return nil
@@ -739,7 +728,9 @@ func (e *Engine) recoverSingleRetry(
 		// webhook on one bad read would be a far larger fault than
 		// the strand it is meant to clear.
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			e.failMissingTarget(webhookDB, webhookID, d)
+			e.failMissingTargetRetry(
+				webhookDB, webhookID, d,
+			)
 
 			return
 		}
@@ -1142,7 +1133,9 @@ func (e *Engine) sweepSingleRetry(
 		// Deleted is terminal, unreadable is not; see
 		// recoverSingleRetry.
 		if errors.Is(err, gorm.ErrRecordNotFound) {
-			e.failMissingTarget(webhookDB, webhookID, d)
+			e.failMissingTargetRetry(
+				webhookDB, webhookID, d,
+			)
 
 			return
 		}
@@ -1256,19 +1249,19 @@ func (e *Engine) failUnretryableRetry(
 	e.failDelivery(webhookDB, d, target.Type, reason)
 }
 
-// failMissingTarget terminally fails a recovered delivery, pending or
-// retrying, whose target row is gone. Restart recovery and the periodic
-// sweep call it for both statuses, so the transition exists once.
+// failMissingTargetRetry terminally fails an orphaned retrying
+// delivery whose target row is gone. Both restart recovery and the
+// periodic sweep call it, so the transition exists once.
 //
-// Until it existed those paths logged the failed lookup and moved on,
-// which left the delivery where it was for the life of the database and
+// Until it existed both paths logged the failed lookup and returned,
+// which left the delivery retrying for the life of the database and
 // the sweep repeating the same error every minute forever. Failing it
 // with a recorded reason is the treatment the other orphaned-retry
 // cases already get, so all of them read alike in the event log.
 //
 // Logged at warn rather than error: a deleted target is an operator
 // action, not a system fault.
-func (e *Engine) failMissingTarget(
+func (e *Engine) failMissingTargetRetry(
 	webhookDB *gorm.DB,
 	webhookID string,
 	d *database.Delivery,
@@ -1281,37 +1274,13 @@ func (e *Engine) failMissingTarget(
 
 	defer e.inflight.release(d.ID)
 
-	// The batch was read before ownership was taken, and a worker may
-	// have settled the delivery and let it go in between. Only a row
-	// still in the status the batch read is failed.
-	row, err := e.loadDelivery(webhookDB, d.ID)
-	if err != nil {
-		e.log.Error(
-			"failed to load delivery",
-			"delivery_id", d.ID,
-			"error", err,
-		)
-
-		return
-	}
-
-	if row.Status != d.Status {
-		e.log.Debug(
-			"delivery already handled, not failed",
-			"delivery_id", d.ID,
-			"status", row.Status,
-		)
-
-		return
-	}
-
 	targetType, reason := e.missingTargetReason(d.TargetID)
 
 	e.log.Warn(
-		"failing recovered delivery: its target no longer exists",
+		"failing orphaned retrying delivery: "+
+			"its target no longer exists",
 		"webhook_id", webhookID,
 		"delivery_id", d.ID,
-		"status", d.Status,
 		"target_id", d.TargetID,
 		"target_type", targetType,
 	)
@@ -1345,14 +1314,15 @@ func (e *Engine) missingTargetReason(
 	if err != nil {
 		return "", fmt.Sprintf(
 			"target %s no longer exists; the delivery "+
-				"has been failed terminally",
+				"cannot be retried and has been failed "+
+				"terminally",
 			targetID,
 		)
 	}
 
 	return target.Type, fmt.Sprintf(
 		"target %q (type %s) was deleted; the delivery "+
-			"has been failed terminally",
+			"cannot be retried and has been failed terminally",
 		target.Name, target.Type,
 	)
 }
@@ -2051,30 +2021,13 @@ func (e *Engine) sendRecoveredDeliveries(
 
 		target, ok := targetMap[deliveries[i].TargetID]
 		if !ok {
-			// A missing entry does not mean the target is gone: the
-			// map is also empty when its query failed. Only a lookup
-			// that finds no row ends the delivery; any other error
-			// leaves it pending for the next sweep. See
-			// recoverSingleRetry.
-			var err error
+			e.log.Error(
+				"target not found for delivery",
+				"delivery_id", deliveries[i].ID,
+				"target_id", deliveries[i].TargetID,
+			)
 
-			target, err = e.loadTarget(deliveries[i].TargetID)
-			if errors.Is(err, gorm.ErrRecordNotFound) {
-				e.failMissingTarget(webhookDB, webhookID, &deliveries[i])
-
-				continue
-			}
-
-			if err != nil {
-				e.log.Error(
-					"failed to load target for recovered delivery",
-					"delivery_id", deliveries[i].ID,
-					"target_id", deliveries[i].TargetID,
-					"error", err,
-				)
-
-				continue
-			}
+			continue
 		}
 
 		if !e.takeForRedispatch(

internal/delivery/engine_lifecycle_test.go

@@ -2,8 +2,6 @@ package delivery_test
 
 import (
 	"context"
-	"fmt"
-	"path/filepath"
 	"testing"
 	"time"
 
@@ -271,88 +269,3 @@ func TestEngine_StopHookHonoursStopTimeout(t *testing.T) {
 
 	requireStopHookExpires(t, lc.hooks[0], "delivery engine")
 }
-
-// deliverToArchive runs one delivery to a database target through
-// the running engine and returns the webhook's archive file path.
-// The archive writer holds the file open afterwards.
-func deliverToArchive(t *testing.T, s iSetup) string {
-	t.Helper()
-
-	deliveryID, task := seedLogTask(t, s)
-	task.TargetType = database.TargetTypeDatabase
-
-	s.Engine.Notify([]delivery.Task{task})
-
-	iWaitForDelivered(t, s.WebhookDB, deliveryID)
-
-	return filepath.Join(
-		filepath.Dir(s.DBMgr.DBPath(s.WebhookID)),
-		fmt.Sprintf("archive-%s.db", s.WebhookID),
-	)
-}
-
-// TestEngine_StopHookClosesArchives is the regression test for an
-// archive split across two files by a clean stop. The engine never
-// closed its archive writers, so after a stop the archived rows
-// could sit in archive-{id}.db-wal while archive-{id}.db held no
-// table at all, and copying the .db on its own gave an empty
-// database.
-func TestEngine_StopHookClosesArchives(t *testing.T) {
-	t.Parallel()
-
-	s := newISetup(t)
-
-	lc := startEngineViaHook(t, s.Engine)
-
-	path := deliverToArchive(t, s)
-	require.FileExists(
-		t, path+"-wal",
-		"an open archive should have a -wal for the stop to remove",
-	)
-
-	require.NoError(t, lc.hooks[0].OnStop(context.Background()))
-
-	wals, err := filepath.Glob(
-		filepath.Join(filepath.Dir(path), "archive-*.db-wal"),
-	)
-	require.NoError(t, err)
-	require.Empty(
-		t, wals, "a clean stop must leave no archive -wal behind",
-	)
-
-	// With no -wal beside it, the row can only be in the .db.
-	count, err := countArchivedRows(path)
-	require.NoError(t, err)
-	require.Equal(t, int64(1), count)
-}
-
-// TestEngine_StopHookTimeoutLeavesArchivesOpen covers a stop whose
-// budget runs out while a worker is still running. The archive
-// writers are left open, as a kill would leave them: closing them
-// would wait for any write in progress, and that worker would then
-// open new writers that nothing closes.
-func TestEngine_StopHookTimeoutLeavesArchivesOpen(t *testing.T) {
-	t.Parallel()
-
-	s := newISetup(t)
-
-	lc := startEngineViaHook(t, s.Engine)
-
-	deliverToArchive(t, s)
-
-	release := make(chan struct{})
-
-	t.Cleanup(func() {
-		close(release)
-		s.Engine.EvictWebhook(s.WebhookID)
-	})
-
-	s.Engine.ExportWedgeWorker(release)
-
-	requireStopHookExpires(t, lc.hooks[0], "delivery engine")
-
-	require.True(
-		t, s.Engine.ExportArchiveHandleOpen(s.WebhookID),
-		"a stop that timed out must not close archive writers",
-	)
-}

internal/delivery/export_test.go

@@ -342,31 +342,6 @@ func (e *Engine) ExportRecoverRetryingDeliveries(
 	e.recoverRetryingDeliveries(webhookDB, webhookID)
 }
 
-// ExportFailMissingTarget exposes failMissingTarget, so a test can hand
-// it a delivery as a batch read it earlier.
-func (e *Engine) ExportFailMissingTarget(
-	webhookDB *gorm.DB,
-	webhookID string,
-	d *database.Delivery,
-) {
-	e.failMissingTarget(webhookDB, webhookID, d)
-}
-
-// ExportSendRecoveredDeliveries exposes sendRecoveredDeliveries, so a
-// test can hand it a target map that lacks a delivery's target.
-func (e *Engine) ExportSendRecoveredDeliveries(
-	ctx context.Context,
-	webhookDB *gorm.DB,
-	deliveries []database.Delivery,
-	webhookID string,
-	targetMap map[string]database.Target,
-	settled map[string]struct{},
-) {
-	e.sendRecoveredDeliveries(
-		ctx, webhookDB, deliveries, webhookID, targetMap, settled,
-	)
-}
-
 // ExportDeliveryCh returns the delivery channel.
 func (e *Engine) ExportDeliveryCh() chan Task {
 	return e.deliveryCh

internal/delivery/redirect_test.go

@@ -339,11 +339,10 @@ func TestRedirectPolicy_StopsAtHopCap(t *testing.T) {
 // The set the redirect policy strips is whatever the delivery path
 // actually put on the wire, so a header added to the forward set is
 // covered without a second edit. A header the event never carried
-// is not in the set, and neither is the inbound Content-Type, because
-// it is not forwarded. Two more are deliberately excluded: a
-// Content-Type configured on the target describes the body, which a
-// 307 carries across hosts, and the inbound User-Agent every real
-// sender supplies is overwritten before the request goes out.
+// is not in the set, and the delivery path's own two are deliberately
+// excluded: Content-Type describes the body, which a 307 carries
+// across hosts, and the inbound User-Agent every real sender supplies
+// is overwritten before the request goes out.
 func TestApplyRequestHeaders_ReportsOriginScopedNames(t *testing.T) {
 	t.Parallel()
 
@@ -372,7 +371,6 @@ func TestApplyRequestHeaders_ReportsOriginScopedNames(t *testing.T) {
 		&delivery.HTTPTargetConfig{
 			Headers: map[string]string{
 				probeHeaderName: probeHeaderValue,
-				"Content-Type":  testContentType,
 			},
 		},
 	)
@@ -380,11 +378,7 @@ func TestApplyRequestHeaders_ReportsOriginScopedNames(t *testing.T) {
 	assert.Equal(t,
 		[]string{probeHeaderName, inboundHeaderName}, names,
 		"both header classes are reported, and only those: "+
-			"Host and the inbound Content-Type are never "+
-			"forwarded, User-Agent is the delivery path's own",
-	)
-	assert.NotContains(t, names, "Content-Type",
-		"a Content-Type configured on the target must survive "+
-			"a cross-origin 307/308 with the body it describes",
+			"Host is never forwarded, Content-Type and "+
+			"User-Agent are the delivery path's own",
 	)
 }

internal/delivery/ssrf.go

@@ -26,7 +26,7 @@ var (
 		"hostname resolved to no IP addresses",
 	)
 	errBlockedIP = errors.New(
-		"blocked private, reserved or cloud metadata address",
+		"blocked private/reserved IP range",
 	)
 	errBlockedMetadata = errors.New(
 		"blocked link-local or cloud instance metadata " +
@@ -37,10 +37,9 @@ var (
 	)
 )
 
-// blockedNetworks is the default blocklist: the private and
-// reserved IP ranges, plus the public cloud metadata addresses,
-// that are blocked to prevent SSRF attacks. An operator can
-// permit specific blocks out of this set with
+// blockedNetworks contains all private/reserved IP ranges
+// that should be blocked to prevent SSRF attacks. An operator
+// can permit specific blocks out of this set with
 // ALLOWED_EGRESS_CIDRS; see Guard.
 //
 //nolint:gochecknoglobals // package-level network list is appropriate here
@@ -123,8 +122,6 @@ func init() {
 		"::1/128",
 		"fc00::/7",
 		"fe80::/10",
-		// Azure WireServer, a public address that serves VM credentials.
-		"168.63.129.16/32",
 	})
 
 	// Every entry is named. The set must not grow or shrink
@@ -219,8 +216,8 @@ func matchesAny(networks []*net.IPNet, ip net.IP) bool {
 }
 
 // isBlockedIP checks whether an IP address falls within
-// the default blocklist, before any operator allowlist is
-// considered.
+// any blocked private/reserved network range, before any
+// operator allowlist is considered.
 func isBlockedIP(ip net.IP) bool {
 	return matchesAny(blockedNetworks, ip)
 }
@@ -323,7 +320,7 @@ func (g *Guard) allows(ip net.IP) bool {
 //
 //  1. alwaysBlockedNetworks is refused before the allowlist is
 //     consulted, so no configured CIDR reaches link-local or a
-//     cloud metadata endpoint at a non-public address.
+//     cloud instance metadata endpoint.
 //  2. The allowlist is consulted next, so a listed private
 //     network becomes reachable.
 //  3. Everything else keeps the default blocklist's answer.

internal/delivery/ssrf_allowlist_test.go

@@ -390,41 +390,6 @@ func TestGuardAllowlist_PublicUnaffected(t *testing.T) {
 	}
 }
 
-// TestGuardAllowlist_AzureWireServerReopenable covers Azure's
-// WireServer, a public address that serves VM credentials. The
-// default guard refuses it, but because it is public it sits in
-// the default blocklist rather than the unconditional set, so an
-// operator who lists it can reach it.
-func TestGuardAllowlist_AzureWireServerReopenable(t *testing.T) {
-	t.Parallel()
-
-	const wireServerIP = "168.63.129.16"
-
-	target := "http://" + wireServerIP + "/?comp=versions"
-
-	defaultGuard := delivery.NewTestGuard()
-
-	err := defaultGuard.ValidateTargetURL(context.Background(), target)
-	require.Error(t, err,
-		"WireServer must be refused with no allowlist set",
-	)
-	assert.NotContains(t, err.Error(), metadataRefusalClause,
-		"WireServer must be refused by the default blocklist, "+
-			"which an allowlist can override",
-	)
-
-	assertDialRefused(t, defaultGuard, target)
-
-	listed := delivery.NewTestGuard(
-		netip.MustParsePrefix(wireServerIP + "/32"),
-	)
-
-	assert.NoError(t,
-		listed.ValidateTargetURL(context.Background(), target),
-		"an operator who lists WireServer must be able to reach it",
-	)
-}
-
 // TestGuardCheckIP_BothPathsShareOneDecision asserts that the
 // validator and the dialer are not two policies that happen to
 // agree: both are defined in terms of checkIP, so the exported

internal/delivery/target_database.go

@@ -277,24 +277,6 @@ func (t *databaseTarget) evict(webhookID string) {
 	)
 }
 
-// evictAll evicts every cached archive writer, exactly as evict
-// does for one webhook. The engine calls it at shutdown, once its
-// workers have returned. Closing the last handle on an archive
-// moves the contents of its -wal into the .db and removes the
-// -wal, so a clean stop leaves each archive as a single file.
-func (t *databaseTarget) evictAll() {
-	t.mu.Lock()
-
-	writers := t.writers
-	t.writers = nil
-
-	t.mu.Unlock()
-
-	for _, w := range writers {
-		w.evict()
-	}
-}
-
 // sweepWebhook prunes one webhook's archive of rows older than
 // expiry, without requiring a write. It returns nil (nothing to
 // do) when the archive file does not exist, so a sweep never

internal/delivery/target_database_evict_test.go

@@ -1,7 +1,6 @@
 package delivery_test
 
 import (
-	"context"
 	"errors"
 	"fmt"
 	"net/http"
@@ -362,46 +361,3 @@ func TestEvictWebhook_LaterDeliveryRecreatesWriter(t *testing.T) {
 		"a later delivery should recreate the writer",
 	)
 }
-
-// TestEngineStop_WriteAfterStopIsRefused proves the engine's stop
-// closes each archive writer the way deleting its webhook does: a
-// write that reaches a writer after the stop is refused, reopens
-// nothing and adds no row.
-func TestEngineStop_WriteAfterStopIsRefused(t *testing.T) {
-	t.Parallel()
-
-	eng, _ := evictTestEngine(t)
-
-	webhookDB := testWebhookDB(t)
-	event := seedEvent(t, webhookDB, `{"archived":true}`)
-	d := seedDatabaseTargetDelivery(t, webhookDB, event, "")
-
-	eng.ExportDeliverDatabase(webhookDB, d)
-
-	w := eng.ExportArchiveWriterFor(event.WebhookID)
-	require.NotNil(t, w)
-	require.True(t, w.HandleOpen())
-
-	require.NoError(t, eng.ExportStop(context.Background()))
-
-	err := w.Write(evictTestRow("ev-after-stop"), 0)
-
-	require.ErrorIs(
-		t, err, delivery.ErrExportArchiveWriterEvicted,
-		"a write after the stop must be refused",
-	)
-	assert.False(
-		t, w.HandleOpen(),
-		"a refused write must not reopen the archive",
-	)
-	assert.False(
-		t, eng.ExportHasArchiveWriter(event.WebhookID),
-		"the stop should empty the registry",
-	)
-
-	count, err := countArchivedRows(w.Path())
-	require.NoError(t, err)
-	assert.Equal(
-		t, int64(1), count, "the refused row must not be written",
-	)
-}

internal/delivery/terminal_state_test.go

@@ -18,17 +18,16 @@ import (
 // https://git.eeqj.de/sneak/webhooker/issues/107: a delivery failed
 // with nothing in its event log to say why, and a retrying delivery
 // whose target was deleted, which used to keep sending and then never
-// terminalise. Section 4 is the same deleted-target gap for a pending
-// delivery: https://git.eeqj.de/sneak/webhooker/issues/293.
+// terminalise.
 
 // tUnknownType is a target type no build implements. It stands in for
 // a target whose type was written by a build that knew a type this one
 // does not.
 const tUnknownType = database.TargetType("pubsub")
 
-// tSeedDeletedTarget creates a target, a delivery against it at the
-// given status with one recorded failed attempt, and then deletes the
-// target the way the source page does.
+// tSeedDeletedTarget creates a target, a retrying delivery against it
+// with one recorded failed attempt, and then deletes the target the
+// way the source page does.
 //
 // It asserts the delete is soft, because that is the whole reason the
 // engine could not tell a deleted target from a target id that never
@@ -37,7 +36,6 @@ func tSeedDeletedTarget(
 	t *testing.T,
 	s iSetup,
 	name, url string,
-	status database.DeliveryStatus,
 ) string {
 	t.Helper()
 
@@ -53,7 +51,8 @@ func tSeedDeletedTarget(
 	)
 
 	d := iSeedDelivery(
-		t, s.WebhookDB, event.ID, targetID, status,
+		t, s.WebhookDB, event.ID, targetID,
+		database.DeliveryStatusRetrying,
 	)
 
 	iSeedFailedResult(t, s.WebhookDB, d.ID)
@@ -174,7 +173,6 @@ func TestRecoverSingleRetry_TargetDeleted(t *testing.T) {
 
 	deliveryID := tSeedDeletedTarget(
 		t, s, "gone-on-recovery", "http://example.com/hook",
-		database.DeliveryStatusRetrying,
 	)
 
 	s.Engine.ExportRecoverWebhookDeliveries(
@@ -212,7 +210,6 @@ func TestSweepSingleRetry_TargetDeleted(t *testing.T) {
 
 	deliveryID := tSeedDeletedTarget(
 		t, s, "gone-on-sweep", "http://example.com/hook",
-		database.DeliveryStatusRetrying,
 	)
 
 	// Twice, because the bug was an error the sweep repeated every
@@ -281,11 +278,11 @@ func TestSweepSingleRetry_TargetNeverExisted(t *testing.T) {
 	)
 }
 
-// TestFailMissingTarget_WritesNoTargetRow holds the new terminal path
-// to the same rule as the existing one: no target row, and so no
+// TestFailMissingTargetRetry_WritesNoTargetRow holds the new terminal
+// path to the same rule as the existing one: no target row, and so no
 // plaintext target config, may be written into the per-webhook event
 // database. See https://git.eeqj.de/sneak/webhooker/issues/206.
-func TestFailMissingTarget_WritesNoTargetRow(
+func TestFailMissingTargetRetry_WritesNoTargetRow(
 	t *testing.T,
 ) {
 	t.Parallel()
@@ -300,7 +297,6 @@ func TestFailMissingTarget_WritesNoTargetRow(
 
 	deliveryID := tSeedDeletedTarget(
 		t, s, "credential-bearing", hookURL,
-		database.DeliveryStatusRetrying,
 	)
 
 	s.Engine.ExportSweepWebhookRetries(
@@ -533,260 +529,3 @@ func TestRecoverSingleRetry_TargetUnreadable_LeavesDeliveryAlone(
 
 	assert.Zero(t, s.Engine.ExportInflightHeld())
 }
-
-// --- 4. A pending delivery whose target is gone ---
-
-func TestRecoverPending_TargetDeleted(t *testing.T) {
-	t.Parallel()
-
-	s := newISetup(t)
-
-	deliveryID := tSeedDeletedTarget(
-		t, s, "gone-while-pending", "http://example.com/hook",
-		database.DeliveryStatusPending,
-	)
-
-	s.Engine.ExportRecoverWebhookDeliveries(
-		context.Background(), s.WebhookID,
-	)
-
-	iAssertStatus(
-		t, s.WebhookDB, deliveryID,
-		database.DeliveryStatusFailed,
-	)
-
-	last := tLastResult(t, s, deliveryID, 2)
-
-	assert.False(t, last.Success)
-	assert.Equal(t, 2, last.AttemptNum)
-	assert.Contains(t, last.Error, "gone-while-pending")
-	assert.Contains(t, last.Error, "was deleted")
-
-	assert.Empty(t, fDrain(s.Engine),
-		"a delivery whose target is gone was sent",
-	)
-	assert.Zero(t, s.Engine.ExportInflightHeld(),
-		"the terminal path leaked its ownership reference",
-	)
-}
-
-// TestRecoverPending_TargetDeleted_LeavesAnOwnedDeliveryAlone: the
-// terminal write takes ownership like every other recovery write, so a
-// delivery the engine still holds is not failed underneath its worker.
-func TestRecoverPending_TargetDeleted_LeavesAnOwnedDeliveryAlone(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	s := newISetup(t)
-
-	deliveryID := tSeedDeletedTarget(
-		t, s, "gone-but-owned", "http://example.com/hook",
-		database.DeliveryStatusPending,
-	)
-
-	require.True(t, s.Engine.ExportRetainDelivery(deliveryID))
-
-	s.Engine.ExportRecoverWebhookDeliveries(
-		context.Background(), s.WebhookID,
-	)
-
-	iAssertStatus(
-		t, s.WebhookDB, deliveryID,
-		database.DeliveryStatusPending,
-	)
-
-	assert.Len(t, iResults(t, s.WebhookDB, deliveryID), 1,
-		"a delivery the engine owns was failed underneath it",
-	)
-}
-
-// TestFailMissingTarget_LeavesASettledDeliveryAlone: the recovery paths
-// read their batch before taking ownership, and a worker may send a
-// delivery and let it go in between. The terminal write goes by the row
-// as it is now, not as the batch read it.
-func TestFailMissingTarget_LeavesASettledDeliveryAlone(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	s := newISetup(t)
-
-	deliveryID := tSeedDeletedTarget(
-		t, s, "gone-after-sending", "http://example.com/hook",
-		database.DeliveryStatusPending,
-	)
-
-	var batch database.Delivery
-
-	require.NoError(t, s.WebhookDB.First(
-		&batch, "id = ?", deliveryID,
-	).Error)
-
-	// A worker settles the delivery after the batch was read.
-	require.NoError(t, s.WebhookDB.Model(&database.Delivery{}).
-		Where("id = ?", deliveryID).
-		Update("status", database.DeliveryStatusDelivered).Error)
-
-	s.Engine.ExportFailMissingTarget(
-		s.WebhookDB, s.WebhookID, &batch,
-	)
-
-	iAssertStatus(
-		t, s.WebhookDB, deliveryID,
-		database.DeliveryStatusDelivered,
-	)
-
-	assert.Len(t, iResults(t, s.WebhookDB, deliveryID), 1,
-		"a delivery settled after the batch read was then failed",
-	)
-	assert.Zero(t, s.Engine.ExportInflightHeld())
-}
-
-// TestSweepPending_TargetDeleted sweeps twice over a batch that also
-// holds a healthy stranded delivery. The one whose target is gone is
-// failed once and then left alone; the healthy one is queued by the
-// first sweep and not again by the second.
-func TestSweepPending_TargetDeleted(t *testing.T) {
-	t.Parallel()
-
-	liveTargetID := uuid.New().String()
-	s := fSweepSetup(t, liveTargetID, "still-there")
-
-	deliveryID := tSeedDeletedTarget(
-		t, s, "gone-on-pending-sweep", "http://example.com/hook",
-		database.DeliveryStatusPending,
-	)
-	rAgePending(t, s.WebhookDB, deliveryID)
-
-	event := iSeedEvent(
-		t, s.WebhookDB, s.WebhookID, `{"target":"live"}`,
-	)
-
-	healthy := iSeedDelivery(
-		t, s.WebhookDB, event.ID, liveTargetID,
-		database.DeliveryStatusPending,
-	)
-	rAgePending(t, s.WebhookDB, healthy.ID)
-
-	ctx := context.Background()
-
-	s.Engine.ExportSweepWebhookRetries(ctx, s.WebhookID)
-
-	tasks := fDrain(s.Engine)
-	require.Len(t, tasks, 1,
-		"the first sweep did not queue the healthy delivery",
-	)
-	assert.Equal(t, healthy.ID, tasks[0].DeliveryID)
-
-	s.Engine.ExportSweepWebhookRetries(ctx, s.WebhookID)
-
-	assert.Empty(t, fDrain(s.Engine),
-		"the second sweep queued a delivery again",
-	)
-
-	iAssertStatus(
-		t, s.WebhookDB, deliveryID,
-		database.DeliveryStatusFailed,
-	)
-
-	last := tLastResult(t, s, deliveryID, 2)
-
-	assert.Contains(t, last.Error, "gone-on-pending-sweep")
-	assert.Contains(t, last.Error, "was deleted")
-}
-
-// TestSendRecoveredDeliveries_TargetMissingFromMap: the batch's target
-// map is empty when its query failed, so every delivery in the batch is
-// looked up on its own. A healthy one is sent to the target that lookup
-// finds.
-func TestSendRecoveredDeliveries_TargetMissingFromMap(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	s := newISetup(t)
-
-	targetID := uuid.New().String()
-
-	iCreateTarget(
-		t, s.MainDB, targetID, s.WebhookID, "found-on-lookup",
-		database.TargetTypeLog, "", 0,
-	)
-
-	event := iSeedEvent(
-		t, s.WebhookDB, s.WebhookID, `{"map":"empty"}`,
-	)
-
-	d := iSeedDelivery(
-		t, s.WebhookDB, event.ID, targetID,
-		database.DeliveryStatusPending,
-	)
-
-	s.Engine.ExportSendRecoveredDeliveries(
-		context.Background(), s.WebhookDB,
-		[]database.Delivery{d}, s.WebhookID,
-		map[string]database.Target{}, nil,
-	)
-
-	tasks := fDrain(s.Engine)
-	require.Len(t, tasks, 1,
-		"the healthy delivery was not queued exactly once",
-	)
-	assert.Equal(t, d.ID, tasks[0].DeliveryID)
-	assert.Equal(t, targetID, tasks[0].TargetID)
-	assert.Equal(t, database.TargetTypeLog, tasks[0].TargetType)
-
-	iAssertStatus(
-		t, s.WebhookDB, d.ID,
-		database.DeliveryStatusPending,
-	)
-}
-
-// TestRecoverPending_TargetUnreadable_LeavesDeliveryAlone: a failed
-// read of the main database is not a deleted target. Restart recovery
-// holds every pending delivery of the webhook in one batch, so failing
-// on this would fail all of them.
-func TestRecoverPending_TargetUnreadable_LeavesDeliveryAlone(
-	t *testing.T,
-) {
-	t.Parallel()
-
-	s := newISetup(t)
-
-	targetID := uuid.New().String()
-
-	iCreateTarget(
-		t, s.MainDB, targetID, s.WebhookID, "healthy",
-		database.TargetTypeLog, "", 0,
-	)
-
-	event := iSeedEvent(
-		t, s.WebhookDB, s.WebhookID, `{"still":"pending"}`,
-	)
-
-	d := iSeedDelivery(
-		t, s.WebhookDB, event.ID, targetID,
-		database.DeliveryStatusPending,
-	)
-
-	sqlDB, err := s.MainDB.DB()
-	require.NoError(t, err)
-	require.NoError(t, sqlDB.Close())
-
-	s.Engine.ExportRecoverPendingDeliveries(
-		context.Background(), s.WebhookDB, s.WebhookID,
-	)
-
-	iAssertStatus(
-		t, s.WebhookDB, d.ID,
-		database.DeliveryStatusPending,
-	)
-
-	assert.Empty(t, iResults(t, s.WebhookDB, d.ID),
-		"an unreadable main database produced a terminal "+
-			"failure row",
-	)
-	assert.Empty(t, fDrain(s.Engine))
-	assert.Zero(t, s.Engine.ExportInflightHeld())
-}

internal/handlers/auth.go

@@ -103,10 +103,9 @@ func (h *Handlers) renderLoginError(
 // The credential check runs BEFORE any rate-limit budget is
 // consulted, and only a failed check spends budget. That is what
 // keeps the single administrative path reachable: behind the reverse
-// proxy this deployment requires, when TRUSTED_PROXIES does not cover
-// it, every client shares one bucket, so a limiter spent on arrival
-// lets any stranger deny the operator's own correct password
-// indefinitely.
+// proxy this deployment requires, with TRUSTED_PROXIES unset, every
+// client shares one bucket, so a limiter spent on arrival lets any
+// stranger deny the operator's own correct password indefinitely.
 //
 // Verifying first means every login POST costs an Argon2id hash, so
 // the work is taken under a bounded number of verification slots.

internal/handlers/auth_test.go

@@ -25,7 +25,7 @@ const (
 
 	// sharedProxyPeer is the whole point of this file. Production is
 	// required to run behind a TLS-terminating reverse proxy, and
-	// when TRUSTED_PROXIES does not cover it every client — attacker
+	// TRUSTED_PROXIES defaults to empty, so every client — attacker
 	// and operator alike — reaches the process from the proxy's
 	// address and shares one rate-limit bucket. Both parties in
 	// these tests therefore use the same RemoteAddr.
@@ -115,11 +115,11 @@ func floodFailures(
 // done-criterion of https://git.eeqj.de/sneak/webhooker/issues/150.
 //
 // The attacker and the operator share one rate-limit bucket, because
-// behind the mandated reverse proxy, when TRUSTED_PROXIES does not
-// cover it, every client keys on the proxy's address. The attacker
-// floods the operator's own username — a single-admin product has a
-// predictable one — far past the failure limit. The operator must
-// still be able to log in with the correct password.
+// behind the mandated reverse proxy with TRUSTED_PROXIES unset every
+// client keys on the proxy's address. The attacker floods the
+// operator's own username — a single-admin product has a predictable
+// one — far past the failure limit. The operator must still be able
+// to log in with the correct password.
 //
 // This fails if credentials stop being verified ahead of the limiter.
 func TestLogin_StrangersFloodCannotLockOutTheOperator(t *testing.T) {

internal/middleware/loginguard.go

@@ -108,10 +108,10 @@ type failureWindow struct {
 //
 // A limiter that spends budget on arrival cannot protect a
 // single-admin product: behind the reverse proxy the deployment
-// requires, when TRUSTED_PROXIES does not cover it, every client
-// keys on the proxy, so a stranger trickling five POSTs a minute
-// keeps the one bucket full and the operator's own correct password
-// is answered 429 forever. There is no second administrative path.
+// requires, with TRUSTED_PROXIES unset, every client keys on the
+// proxy, so a stranger trickling five POSTs a minute keeps the one
+// bucket full and the operator's own correct password is answered 429
+// forever. There is no second administrative path.
 //
 // So budget is spent only by a FAILED verification. A correct
 // password is never throttled, whatever the counters say, which is

internal/middleware/ratelimit.go

@@ -123,8 +123,9 @@ func bucketKey(addr netip.Addr) string {
 	return prefix.String()
 }
 
-// isTrustedProxy reports whether addr belongs to a network in
-// TRUSTED_PROXIES, which by default is the RFC 1918 private ranges.
+// isTrustedProxy reports whether addr belongs to a network the
+// operator listed in TRUSTED_PROXIES. The list is empty by default,
+// so by default nothing is trusted.
 func (m *Middleware) isTrustedProxy(addr netip.Addr) bool {
 	for _, prefix := range m.params.Config.TrustedProxies {
 		if prefix.Contains(addr) {

internal/middleware/ratelimit_test.go

@@ -426,8 +426,8 @@ func assertSharedBucket(
 }
 
 // TestRateLimitKey_SpoofedForwardedFromUntrustedPeer is the test
-// this gating exists for: from a peer that is not a trusted
-// proxy, a client that rotates a forwarded header on every
+// this gating exists for: with no trusted proxies configured (the
+// default), a client that rotates a forwarded header on every
 // request must stay in one bucket. If forwarded headers were
 // trusted unconditionally, each spoofed value would mint a fresh
 // bucket and the limit would stop no one.

internal/middleware/recoverer.go

@@ -133,11 +133,6 @@ func (w *recoverResponseWriter) Unwrap() http.ResponseWriter {
 // what the access log records and the metrics count, and outside the
 // sentryhttp handler, whose Repanic option depends on something
 // further out recovering what it re-raises.
-//
-// Unlike http.Error on its own, it deletes any Set-Cookie the handler
-// set before panicking, because a request that failed must not hand
-// the client a credential; every other header is left to http.Error.
-// See https://git.eeqj.de/sneak/webhooker/issues/193.
 func (s *Middleware) Recoverer() func(http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
 		return http.HandlerFunc(func(
@@ -169,8 +164,6 @@ func (s *Middleware) Recoverer() func(http.Handler) http.Handler {
 					return
 				}
 
-				rw.Header().Del("Set-Cookie")
-
 				http.Error(
 					rw,
 					http.StatusText(

internal/middleware/recoverer_test.go

@@ -304,44 +304,16 @@ func TestRecovererRepanicsErrAbortHandler(t *testing.T) {
 	)
 }
 
-// TestRecovererDropsSetCookieFromTheRecovered500 covers a handler that
-// sets a cookie and a redirect target and then panics before sending
-// anything. A request that failed must not hand the client a
-// credential, so the 500 carries no cookie; Location is left alone.
-func TestRecovererDropsSetCookieFromTheRecovered500(t *testing.T) {
-	t.Parallel()
-
-	probe := newRecovererProbe(
-		t, false,
-		func(w http.ResponseWriter, _ *http.Request) {
-			w.Header().Set("Set-Cookie", "session=x")
-			w.Header().Set("Location", "/after")
-
-			panic(panicMarker)
-		},
-	)
-
-	resp, err := probe.get(t)
-	require.NoError(t, err)
-	require.NoError(t, resp.Body.Close())
-
-	assert.Equal(t, http.StatusInternalServerError, resp.StatusCode)
-	assert.Empty(t, resp.Cookies())
-	assert.Equal(t, "/after", resp.Header.Get("Location"))
-}
-
 // TestRecovererKeepsAnAlreadyCommittedResponse covers a handler that
 // panics after sending its status. The bytes are already on the wire,
-// cookie included, so a second WriteHeader would change nothing the
-// client sees and would draw net/http's "superfluous
-// response.WriteHeader" report.
+// so a second WriteHeader would change nothing the client sees and
+// would draw net/http's "superfluous response.WriteHeader" report.
 func TestRecovererKeepsAnAlreadyCommittedResponse(t *testing.T) {
 	t.Parallel()
 
 	probe := newRecovererProbe(
 		t, false,
 		func(w http.ResponseWriter, _ *http.Request) {
-			w.Header().Set("Set-Cookie", "session=x")
 			w.WriteHeader(committedStatus)
 			_, _ = w.Write([]byte("partial"))
 
@@ -359,7 +331,6 @@ func TestRecovererKeepsAnAlreadyCommittedResponse(t *testing.T) {
 
 	assert.Equal(t, committedStatus, resp.StatusCode)
 	assert.Equal(t, "partial", string(body))
-	assert.Len(t, resp.Cookies(), 1)
 
 	record := probe.panicRecord(t)
 	assert.Equal(t, panicMarker, record["panic"])

internal/server/routes.go

@@ -140,12 +140,11 @@ func (s *Server) setupPageRoutes() {
 		r.Use(s.mw.NoCache())
 
 		// The login POST carries no pre-emptive rate limiter. Behind
-		// the reverse proxy production requires, when TRUSTED_PROXIES
-		// does not cover it, every client shares one bucket, so a
-		// limiter spent on arrival lets any stranger deny the operator
-		// the only administrative path. The handler verifies
-		// credentials first and charges only failures; see
-		// Handlers.authenticateUser.
+		// the reverse proxy production requires, with TRUSTED_PROXIES
+		// unset, every client shares one bucket, so a limiter spent
+		// on arrival lets any stranger deny the operator the only
+		// administrative path. The handler verifies credentials first
+		// and charges only failures; see Handlers.authenticateUser.
 		r.Get("/login", s.h.HandleLoginPage())
 		r.Post("/login", s.h.HandleLoginSubmit())