refactor auth interface to return error when verify failure (#22119)

This PR changed the Auth interface signature from 
`Verify(http *http.Request, w http.ResponseWriter, store DataStore, sess
SessionStore) *user_model.User`
to 
`Verify(http *http.Request, w http.ResponseWriter, store DataStore, sess
SessionStore) (*user_model.User, error)`.

There is a new return argument `error` which means the verification
condition matched but verify process failed, we should stop the auth
process.

Before this PR, when return a `nil` user, we don't know the reason why
it returned `nil`. If the match condition is not satisfied or it
verified failure? For these two different results, we should have
different handler. If the match condition is not satisfied, we should
try next auth method and if there is no more auth method, it's an
anonymous user. If the condition matched but verify failed, the auth
process should be stop and return immediately.

This will fix #20563

Co-authored-by: KN4CK3R <admin@oldschoolhack.me>
Co-authored-by: Jason Song <i@wolfogre.com>

routers/api/packages/api.go

@@ -11,6 +11,7 @@ import (
 
 	"code.gitea.io/gitea/models/perm"
 	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/web"
 	"code.gitea.io/gitea/routers/api/packages/composer"
@@ -58,7 +59,13 @@ func CommonRoutes(ctx gocontext.Context) *web.Route {
 
 	authGroup := auth.NewGroup(authMethods...)
 	r.Use(func(ctx *context.Context) {
-		ctx.Doer = authGroup.Verify(ctx.Req, ctx.Resp, ctx, ctx.Session)
+		var err error
+		ctx.Doer, err = authGroup.Verify(ctx.Req, ctx.Resp, ctx, ctx.Session)
+		if err != nil {
+			log.Error("Verify: %v", err)
+			ctx.Error(http.StatusUnauthorized, "authGroup.Verify")
+			return
+		}
 		ctx.IsSigned = ctx.Doer != nil
 	})
 
@@ -321,7 +328,13 @@ func ContainerRoutes(ctx gocontext.Context) *web.Route {
 
 	authGroup := auth.NewGroup(authMethods...)
 	r.Use(func(ctx *context.Context) {
-		ctx.Doer = authGroup.Verify(ctx.Req, ctx.Resp, ctx, ctx.Session)
+		var err error
+		ctx.Doer, err = authGroup.Verify(ctx.Req, ctx.Resp, ctx, ctx.Session)
+		if err != nil {
+			log.Error("Failed to verify user: %v", err)
+			ctx.Error(http.StatusUnauthorized, "Verify")
+			return
+		}
 		ctx.IsSigned = ctx.Doer != nil
 	})
 

routers/api/packages/conan/auth.go

@@ -19,22 +19,22 @@ func (a *Auth) Name() string {
 }
 
 // Verify extracts the user from the Bearer token
-func (a *Auth) Verify(req *http.Request, w http.ResponseWriter, store auth.DataStore, sess auth.SessionStore) *user_model.User {
+func (a *Auth) Verify(req *http.Request, w http.ResponseWriter, store auth.DataStore, sess auth.SessionStore) (*user_model.User, error) {
 	uid, err := packages.ParseAuthorizationToken(req)
 	if err != nil {
 		log.Trace("ParseAuthorizationToken: %v", err)
-		return nil
+		return nil, err
 	}
 
 	if uid == 0 {
-		return nil
+		return nil, nil
 	}
 
 	u, err := user_model.GetUserByID(req.Context(), uid)
 	if err != nil {
 		log.Error("GetUserByID:  %v", err)
-		return nil
+		return nil, err
 	}
 
-	return u
+	return u, nil
 }

routers/api/packages/container/auth.go

@@ -20,25 +20,25 @@ func (a *Auth) Name() string {
 
 // Verify extracts the user from the Bearer token
 // If it's an anonymous session a ghost user is returned
-func (a *Auth) Verify(req *http.Request, w http.ResponseWriter, store auth.DataStore, sess auth.SessionStore) *user_model.User {
+func (a *Auth) Verify(req *http.Request, w http.ResponseWriter, store auth.DataStore, sess auth.SessionStore) (*user_model.User, error) {
 	uid, err := packages.ParseAuthorizationToken(req)
 	if err != nil {
 		log.Trace("ParseAuthorizationToken: %v", err)
-		return nil
+		return nil, err
 	}
 
 	if uid == 0 {
-		return nil
+		return nil, nil
 	}
 	if uid == -1 {
-		return user_model.NewGhostUser()
+		return user_model.NewGhostUser(), nil
 	}
 
 	u, err := user_model.GetUserByID(req.Context(), uid)
 	if err != nil {
 		log.Error("GetUserByID:  %v", err)
-		return nil
+		return nil, err
 	}
 
-	return u
+	return u, nil
 }

routers/api/packages/nuget/auth.go

@@ -20,19 +20,20 @@ func (a *Auth) Name() string {
 }
 
 // https://docs.microsoft.com/en-us/nuget/api/package-publish-resource#request-parameters
-func (a *Auth) Verify(req *http.Request, w http.ResponseWriter, store auth.DataStore, sess auth.SessionStore) *user_model.User {
+func (a *Auth) Verify(req *http.Request, w http.ResponseWriter, store auth.DataStore, sess auth.SessionStore) (*user_model.User, error) {
 	token, err := auth_model.GetAccessTokenBySHA(req.Header.Get("X-NuGet-ApiKey"))
 	if err != nil {
 		if !(auth_model.IsErrAccessTokenNotExist(err) || auth_model.IsErrAccessTokenEmpty(err)) {
 			log.Error("GetAccessTokenBySHA: %v", err)
+			return nil, err
 		}
-		return nil
+		return nil, nil
 	}
 
 	u, err := user_model.GetUserByID(req.Context(), token.UID)
 	if err != nil {
 		log.Error("GetUserByID:  %v", err)
-		return nil
+		return nil, err
 	}
 
 	token.UpdatedUnix = timeutil.TimeStampNow()
@@ -40,5 +41,5 @@ func (a *Auth) Verify(req *http.Request, w http.ResponseWriter, store auth.DataS
 		log.Error("UpdateAccessToken:  %v", err)
 	}
 
-	return u
+	return u, nil
 }