chore: initialize Gitea v1.27.2 fork

Includes direct password setup links in registration emails.

Assisted-by: Codex:GPT-5

modules/auth/openid/openid.go

@@ -0,0 +1,55 @@
+// Copyright 2017 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package openid
+
+import (
+	"net/http"
+	"sync"
+	"time"
+
+	"gitea.dev/modules/hostmatcher"
+	"gitea.dev/modules/proxy"
+	"gitea.dev/modules/setting"
+
+	"github.com/yohcop/openid-go"
+)
+
+// For the demo, we use in-memory infinite storage nonce and discovery
+// cache. In your app, do not use this as it will eat up memory and
+// never
+// free it. Use your own implementation, on a better database system.
+// If you have multiple servers for example, you may need to share at
+// least
+// the nonceStore between them.
+var (
+	nonceStore     = openid.NewSimpleNonceStore()
+	discoveryCache = newTimedDiscoveryCache(24 * time.Hour)
+
+	// openIDInstance does discovery/verification via an SSRF-protected client, so a user-supplied
+	// OpenID identifier can't reach internal/loopback/reserved addresses. It honors the operator's
+	// [security] ALLOWED_HOST_LIST (empty defaults to "external"), matching the avatar/webhook/migration
+	// clients, and validates the proxy path too. Lazy: reads proxy/settings once.
+	openIDInstance = sync.OnceValue(func() *openid.OpenID {
+		allowList := hostmatcher.ParseHostMatchList("security.ALLOWED_HOST_LIST", setting.Security.AllowedHostList)
+		return openid.NewOpenID(&http.Client{
+			Timeout:   30 * time.Second,
+			Transport: hostmatcher.NewHTTPTransport("openid", allowList, nil, proxy.Proxy(), setting.Proxy.ProxyURLFixed, nil),
+		})
+	})
+)
+
+// Verify handles response from OpenID provider
+func Verify(fullURL string) (id string, err error) {
+	return openIDInstance().Verify(fullURL, discoveryCache, nonceStore)
+}
+
+// Normalize normalizes an OpenID URI
+func Normalize(url string) (id string, err error) {
+	return openid.Normalize(url)
+}
+
+// RedirectURL redirects browser
+func RedirectURL(id, callbackURL, realm string) (string, error) {
+	return openIDInstance().RedirectURL(id, callbackURL, realm)
+}