check user and repo for redirects when using git via SSH transport

cmd/serv.go

@@ -229,11 +229,6 @@ func runServ(ctx context.Context, c *cli.Command) error {
 	username := repoPathFields[0]
 	reponame := strings.TrimSuffix(repoPathFields[1], ".git") // “the-repo-name" or "the-repo-name.wiki"
 
-	// LowerCase and trim the repoPath as that's how they are stored.
-	// This should be done after splitting the repoPath into username and reponame
-	// so that username and reponame are not affected.
-	repoPath = strings.ToLower(strings.TrimSpace(repoPath))
-
 	if !repo.IsValidSSHAccessRepoName(reponame) {
 		return fail(ctx, "Invalid repo name", "Invalid repo name: %s", reponame)
 	}
@@ -280,6 +275,11 @@ func runServ(ctx context.Context, c *cli.Command) error {
 		return fail(ctx, extra.UserMsg, "ServCommand failed: %s", extra.Error)
 	}
 
+	// LowerCase and trim the repoPath as that's how they are stored.
+	// This should be done after splitting the repoPath into username and reponame
+	// so that username and reponame are not affected.
+	repoPath = strings.ToLower(results.OwnerName + "/" + results.RepoName + ".git")
+
 	// LFS SSH protocol
 	if verb == git.CmdVerbLfsTransfer {
 		token, err := getLFSAuthToken(ctx, lfsVerb, results)

models/fixtures/user_redirect.yml

@@ -2,3 +2,7 @@
   id: 1
   lower_name: olduser1
   redirect_user_id: 1
+-
+  id: 2
+  lower_name: olduser2
+  redirect_user_id: 2

routers/private/serv.go

@@ -108,6 +108,18 @@ func ServCommand(ctx *context.PrivateContext) {
 		results.RepoName = repoName[:len(repoName)-5]
 	}
 
+	// Check if there is a user redirect for the requested owner
+	redirectedUserID, err := user_model.LookupUserRedirect(ctx, results.OwnerName)
+	if err == nil {
+		owner, err := user_model.GetUserByID(ctx, redirectedUserID)
+		if err == nil {
+			log.Info("User %s has been redirected to %s", results.OwnerName, owner.Name)
+			results.OwnerName = owner.Name
+		} else {
+			log.Warn("User %s has a redirect to user with ID %d, but no user with this ID could be found. Trying without redirect...", results.OwnerName, redirectedUserID)
+		}
+	}
+
 	owner, err := user_model.GetUserByName(ctx, results.OwnerName)
 	if err != nil {
 		if user_model.IsErrUserNotExist(err) {
@@ -131,6 +143,19 @@ func ServCommand(ctx *context.PrivateContext) {
 		return
 	}
 
+	redirectedRepoID, err := repo_model.LookupRedirect(ctx, owner.ID, results.RepoName)
+	if err == nil {
+		redirectedRepo, err := repo_model.GetRepositoryByID(ctx, redirectedRepoID)
+		if err == nil {
+			log.Info("Repository %s/%s has been redirected to %s/%s", results.OwnerName, results.RepoName, redirectedRepo.OwnerName, redirectedRepo.Name)
+			results.RepoName = redirectedRepo.Name
+			results.OwnerName = redirectedRepo.OwnerName
+			owner.ID = redirectedRepo.OwnerID
+		} else {
+			log.Warn("Repo %s/%s has a redirect to repo with ID %d, but no repo with this ID could be found. Trying without redirect...", results.OwnerName, results.RepoName, redirectedRepoID)
+		}
+	}
+
 	// Now get the Repository and set the results section
 	repoExist := true
 	repo, err := repo_model.GetRepositoryByName(ctx, owner.ID, results.RepoName)

tests/integration/git_ssh_redirect_test.go

@@ -0,0 +1,42 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package integration
+
+import (
+	"fmt"
+	"net/url"
+	"testing"
+
+	auth_model "code.gitea.io/gitea/models/auth"
+)
+
+func TestGitSSHRedirect(t *testing.T) {
+	onGiteaRun(t, testGitSSHRedirect)
+}
+
+func testGitSSHRedirect(t *testing.T, u *url.URL) {
+	apiTestContext := NewAPITestContext(t, "user2", "repo1", auth_model.AccessTokenScopeWriteRepository, auth_model.AccessTokenScopeWriteUser)
+
+	withKeyFile(t, "my-testing-key", func(keyFile string) {
+		t.Run("CreateUserKey", doAPICreateUserKey(apiTestContext, "test-key", keyFile))
+
+		testCases := []struct {
+			testName string
+			userName string
+			repoName string
+		}{
+			{"Test untouched", "user2", "repo1"},
+			{"Test renamed user", "olduser2", "repo1"},
+			{"Test renamed repo", "user2", "oldrepo1"},
+			{"Test renamed user and repo", "olduser2", "oldrepo1"},
+		}
+
+		for _, tc := range testCases {
+			t.Run(tc.testName, func(t *testing.T) {
+				cloneURL := createSSHUrl(fmt.Sprintf("%s/%s.git", tc.userName, tc.repoName), u)
+				t.Run("Clone", doGitClone(t.TempDir(), cloneURL))
+			})
+		}
+	})
+}