Allow explicit local WebAuthn ports

CHANGELOG.md

@@ -2,6 +2,15 @@
 
 # Changelog
 
+## v0.1.0-preview.15 — 2026-09-03
+
+- Permit applications to opt into an exact non-default HTTPS WebAuthn origin
+  port for `localhost` and reserved `.test` relying-party IDs. The configured
+  origin remains exact, production origins remain portless by default, and
+  malformed, default, non-canonical, zero, or out-of-range ports fail closed.
+- Record the Gamertan local-Caddy dogfood pressure that required this explicit
+  development boundary without weakening cross-origin ceremony rejection.
+
 ## v0.1.0-preview.14 — 2026-09-03
 
 - Reject header-only, truncated, and structurally invalid PDF uploads in the

README.md

@@ -17,7 +17,7 @@ router, handlers, HTML, authorization decisions, cache behavior, and
 deployment. Adopt one boundary at a time; Go compiles and links only the
 packages you import.
 
-> **Public preview:** `v0.1.0-preview.13`. APIs may change before a stable
+> **Public preview:** `v0.1.0-preview.15`. APIs may change before a stable
 > release. Linux is the maintained release platform.
 
 ## Why Web Foundations?
@@ -57,14 +57,14 @@ owns—and, just as importantly, what remains application policy.
 Pin the preview in an application module:
 
 ```bash
-go get gamertan.com/web@v0.1.0-preview.13
+go get gamertan.com/web@v0.1.0-preview.15
 go mod verify
 ```
 
 An application may name the first package it intends to adopt:
 
 ```bash
-go get gamertan.com/web/requestmeta@v0.1.0-preview.13
+go get gamertan.com/web/requestmeta@v0.1.0-preview.15
 ```
 
 The version belongs to the `gamertan.com/web` module. See the

authwebauthn/service.go

@@ -12,8 +12,10 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"net"
 	"net/url"
 	"regexp"
+	"strconv"
 	"strings"
 	"time"
 
@@ -39,6 +41,11 @@ type Config struct {
 	RPID          string
 	RPDisplayName string
 	Origin        string
+	// AllowDevelopmentPort permits an explicit non-default HTTPS port only
+	// for localhost or a reserved .test relying-party ID. Production origins
+	// remain portless, while local applications can terminate trusted HTTPS
+	// without requiring a privileged listener.
+	AllowDevelopmentPort    bool
 	EnrollmentLifetime      time.Duration
 	RegistrationTTL         time.Duration
 	LoginTTL                time.Duration
@@ -66,7 +73,7 @@ func New(repository Repository, authService *auth.Service, config Config) (*Serv
 	if repository == nil || authService == nil {
 		return nil, errors.New("authwebauthn: repository and auth service are required")
 	}
-	if err := validateOrigin(config.RPID, config.Origin); err != nil {
+	if err := validateOrigin(config.RPID, config.Origin, config.AllowDevelopmentPort); err != nil {
 		return nil, err
 	}
 	if strings.TrimSpace(config.RPDisplayName) == "" || len(config.RPDisplayName) > 80 {
@@ -725,12 +732,24 @@ func passwordMigrationBinding(userID string) [32]byte {
 	return BindingDigest([]byte("gamertan-web/password-to-passkey/v1\x00" + userID))
 }
 
-func validateOrigin(rpID, rawOrigin string) error {
+func validateOrigin(rpID, rawOrigin string, allowDevelopmentPort bool) error {
 	if strings.TrimSpace(rpID) == "" || strings.TrimSpace(rawOrigin) == "" {
 		return errors.New("authwebauthn: relying-party ID and origin are required")
 	}
 	origin, err := url.Parse(rawOrigin)
-	if err != nil || origin.Scheme != "https" || origin.Hostname() != rpID || origin.Port() != "" || origin.User != nil || origin.Path != "" || origin.RawQuery != "" || origin.Fragment != "" {
+	if err != nil || origin.Scheme != "https" || origin.Hostname() != rpID || origin.User != nil || origin.Path != "" || origin.RawQuery != "" || origin.Fragment != "" {
+		return errors.New("authwebauthn: origin must be the exact HTTPS relying-party origin")
+	}
+	port := origin.Port()
+	if port == "" {
+		if origin.Host != rpID {
+			return errors.New("authwebauthn: origin must be the exact HTTPS relying-party origin")
+		}
+		return nil
+	}
+	developmentRP := rpID == "localhost" || strings.HasSuffix(rpID, ".test")
+	value, portErr := strconv.ParseUint(port, 10, 16)
+	if !allowDevelopmentPort || !developmentRP || portErr != nil || value == 0 || value == 443 || strconv.FormatUint(value, 10) != port || origin.Host != net.JoinHostPort(rpID, port) {
 		return errors.New("authwebauthn: origin must be the exact HTTPS relying-party origin")
 	}
 	return nil

authwebauthn/service_test.go

@@ -231,11 +231,25 @@ func TestConfigurationAndEntropyFailures(t *testing.T) {
 		{RPID: "tend.gamertan.com", RPDisplayName: "Tend", Origin: "http://tend.gamertan.com"},
 		{RPID: "tend.gamertan.com", RPDisplayName: "Tend", Origin: "https://other.gamertan.com"},
 		{RPID: "tend.gamertan.com", RPDisplayName: "Tend", Origin: "https://tend.gamertan.com/path"},
+		{RPID: "localhost", RPDisplayName: "Tend", Origin: "https://localhost:8443"},
+		{RPID: "tend.gamertan.com", RPDisplayName: "Tend", Origin: "https://tend.gamertan.com:8443", AllowDevelopmentPort: true},
+		{RPID: "localhost", RPDisplayName: "Tend", Origin: "https://localhost:443", AllowDevelopmentPort: true},
+		{RPID: "localhost", RPDisplayName: "Tend", Origin: "https://localhost:08443", AllowDevelopmentPort: true},
+		{RPID: "localhost", RPDisplayName: "Tend", Origin: "https://localhost:0", AllowDevelopmentPort: true},
 	} {
 		if _, err = authwebauthn.New(store, authService, config); err == nil {
 			t.Fatalf("accepted config=%+v", config)
 		}
 	}
+	for _, config := range []authwebauthn.Config{
+		{RPID: "localhost", RPDisplayName: "Tend Local", Origin: "https://localhost:8443", AllowDevelopmentPort: true},
+		{RPID: "tend.test", RPDisplayName: "Tend Local", Origin: "https://tend.test:8443", AllowDevelopmentPort: true},
+	} {
+		configured, configureErr := authwebauthn.New(store, authService, config)
+		if configureErr != nil || configured == nil {
+			t.Fatalf("development config=%+v service=%v err=%v", config, configured, configureErr)
+		}
+	}
 	service, err := authwebauthn.New(store, authService, authwebauthn.Config{RPID: "tend.gamertan.com", RPDisplayName: "Tend", Origin: "https://tend.gamertan.com", Random: failingReader{}})
 	if err != nil {
 		t.Fatal(err)

docs/DOGFOOD.md

@@ -49,3 +49,8 @@ application concern belongs in the shared module.
   passkey and replacement code digests. `authrecovery.BeginPasskey` and
   `FinishPasskey` now provide that boundary without creating an authenticated
   session; Gamertan keeps the raw grant only in a short-lived HttpOnly cookie.
+- A portless-only WebAuthn origin rule made an unprivileged local HTTPS
+  exercise impossible even though WebAuthn origins include ports. The passkey
+  service now permits an explicit development port only when applications opt
+  in and the RP ID is `localhost` or reserved `.test`; production origins keep
+  the original portless default.

docs/GETTING_STARTED.md

@@ -26,7 +26,7 @@ The packages are ordinary Go imports. Pin the current preview and verify its
 module checksum:
 
 ```bash
-go get gamertan.com/web/requestmeta@v0.1.0-preview.13
+go get gamertan.com/web/requestmeta@v0.1.0-preview.15
 go mod verify
 ```
 

docs/MODULES.md

@@ -18,7 +18,7 @@ import "gamertan.com/web/requestmeta"
 and request the containing module at an exact version:
 
 ```bash
-go get gamertan.com/web/requestmeta@v0.1.0-preview.13
+go get gamertan.com/web/requestmeta@v0.1.0-preview.15
 ```
 
 Only imported packages are compiled and linked. The packages nevertheless

docs/PASSKEYS.md

@@ -9,6 +9,11 @@ authorization decisions, session cookie, HTML, and local recovery command.
 ## Fixed security policy
 
 - Use an exact HTTPS origin whose hostname equals the relying-party ID.
+- Keep production origins portless. For local development only,
+  `AllowDevelopmentPort` permits one explicit non-default port when the RP ID
+  is exactly `localhost` or beneath the reserved `.test` top-level domain. The
+  configured origin, browser `Origin`, and WebAuthn verifier origin must still
+  match exactly.
 - Reject cross-origin ceremonies.
 - Require discoverable credentials and user verification.
 - Request no attestation conveyance.