Reset Session ID on login (#18018)

* Reset Session ID on login

When logging in the SessionID should be reset and the session cleaned up.

Signed-off-by: Andrew Thornton <art27@cantab.net>

* with new session.RegenerateID function

Signed-off-by: Andrew Thornton <art27@cantab.net>

* update go-chi/session

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Ensure that session id is changed after oauth data is set and between account linking pages too

Signed-off-by: Andrew Thornton <art27@cantab.net>

* placate lint

Signed-off-by: Andrew Thornton <art27@cantab.net>

* as per review

Signed-off-by: Andrew Thornton <art27@cantab.net>

9 files changed, 121 insertions, 11 deletions

diff --git a/go.mod b/go.mod
index 91bcae3e56..b608790e0c 100644
--- a/go.mod
+++ b/go.mod
@@ -9,7 +9,7 @@ require (
 	gitea.com/go-chi/binding v0.0.0-20211013065440-d16dc407c2be
 	gitea.com/go-chi/cache v0.0.0-20211013020926-78790b11abf1
 	gitea.com/go-chi/captcha v0.0.0-20211013065431-70641c1a35d5
-	gitea.com/go-chi/session v0.0.0-20211013065435-7d334f340c09
+	gitea.com/go-chi/session v0.0.0-20211218221615-e3605d8b28b8
 	gitea.com/lunny/levelqueue v0.4.1
 	github.com/42wim/sshsig v0.0.0-20211121163825-841cf5bbc121
 	github.com/Microsoft/go-winio v0.5.0 // indirect
diff --git a/go.sum b/go.sum
index e9b3ecbc79..d817e97669 100644
--- a/go.sum
+++ b/go.sum
@@ -48,8 +48,8 @@ gitea.com/go-chi/cache v0.0.0-20211013020926-78790b11abf1 h1:Z7DcvTkxt8ovcENgPsQ
 gitea.com/go-chi/cache v0.0.0-20211013020926-78790b11abf1/go.mod h1:k2V/gPDEtXGjjMGuBJiapffAXTv76H4snSmlJRLUhH0=
 gitea.com/go-chi/captcha v0.0.0-20211013065431-70641c1a35d5 h1:J/1i8u40TbcLP/w2w2KCkgW2PelIqYkD5UOwu8IOvVU=
 gitea.com/go-chi/captcha v0.0.0-20211013065431-70641c1a35d5/go.mod h1:hQ9SYHKdOX968wJglb/NMQ+UqpOKwW4L+EYdvkWjHSo=
-gitea.com/go-chi/session v0.0.0-20211013065435-7d334f340c09 h1:1+K+6uOXrnSfLHXvu8jpuoNEWA3/NULOlLSRZwaij+c=
-gitea.com/go-chi/session v0.0.0-20211013065435-7d334f340c09/go.mod h1:fc/pjt5EqNKgqQXYzcas1Z5L5whkZHyOvTA7OzWVJck=
+gitea.com/go-chi/session v0.0.0-20211218221615-e3605d8b28b8 h1:tJQRXgZigkLeeW9LPlps9G9aMoE6LAmqigLA+wxmd1Q=
+gitea.com/go-chi/session v0.0.0-20211218221615-e3605d8b28b8/go.mod h1:fc/pjt5EqNKgqQXYzcas1Z5L5whkZHyOvTA7OzWVJck=
 gitea.com/lunny/levelqueue v0.4.1 h1:RZ+AFx5gBsZuyqCvofhAkPQ9uaVDPJnsULoJZIYaJNw=
 gitea.com/lunny/levelqueue v0.4.1/go.mod h1:HBqmLbz56JWpfEGG0prskAV97ATNRoj5LDmPicD22hU=
 gitea.com/xorm/sqlfiddle v0.0.0-20180821085327-62ce714f951a h1:lSA0F4e9A2NcQSqGqTOXqu2aRi/XEQxDCBwM8yJtE6s=
diff --git a/modules/session/store.go b/modules/session/store.go
index 529187d3be..8c5d7d82eb 100644
--- a/modules/session/store.go
+++ b/modules/session/store.go
@@ -4,9 +4,21 @@
 
 package session
 
+import (
+	"net/http"
+
+	"gitea.com/go-chi/session"
+)
+
 // Store represents a session store
 type Store interface {
 	Get(interface{}) interface{}
 	Set(interface{}, interface{}) error
 	Delete(interface{}) error
 }
+
+// RegenerateSession regenerates the underlying session and returns the new store
+func RegenerateSession(resp http.ResponseWriter, req *http.Request) (Store, error) {
+	s, err := session.RegenerateSession(resp, req)
+	return s, err
+}
diff --git a/routers/web/user/auth.go b/routers/web/user/auth.go
index 9f7796b9e5..356a907859 100644
--- a/routers/web/user/auth.go
+++ b/routers/web/user/auth.go
@@ -22,6 +22,7 @@ import (
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/password"
 	"code.gitea.io/gitea/modules/recaptcha"
+	"code.gitea.io/gitea/modules/session"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/timeutil"
 	"code.gitea.io/gitea/modules/web"
@@ -90,6 +91,10 @@ func AutoSignIn(ctx *context.Context) (bool, error) {
 
 	isSucceed = true
 
+	if _, err := session.RegenerateSession(ctx.Resp, ctx.Req); err != nil {
+		return false, fmt.Errorf("unable to RegenerateSession: Error: %w", err)
+	}
+
 	// Set session IDs
 	if err := ctx.Session.Set("uid", u.ID); err != nil {
 		return false, err
@@ -256,6 +261,11 @@ func SignInPost(ctx *context.Context) {
 		return
 	}
 
+	if _, err := session.RegenerateSession(ctx.Resp, ctx.Req); err != nil {
+		ctx.ServerError("UserSignIn: Unable to set regenerate session", err)
+		return
+	}
+
 	// User will need to use 2FA TOTP or U2F, save data
 	if err := ctx.Session.Set("twofaUid", u.ID); err != nil {
 		ctx.ServerError("UserSignIn: Unable to set twofaUid in session", err)
@@ -419,6 +429,9 @@ func TwoFactorScratchPost(ctx *context.Context) {
 		}
 
 		handleSignInFull(ctx, u, remember, false)
+		if ctx.Written() {
+			return
+		}
 		ctx.Flash.Info(ctx.Tr("auth.twofa_scratch_used"))
 		ctx.Redirect(setting.AppSubURL + "/user/settings/security")
 		return
@@ -526,6 +539,9 @@ func U2FSign(ctx *context.Context) {
 				}
 			}
 			redirect := handleSignInFull(ctx, user, remember, false)
+			if ctx.Written() {
+				return
+			}
 			if redirect == "" {
 				redirect = setting.AppSubURL + "/"
 			}
@@ -538,7 +554,11 @@ func U2FSign(ctx *context.Context) {
 
 // This handles the final part of the sign-in process of the user.
 func handleSignIn(ctx *context.Context, u *user_model.User, remember bool) {
-	handleSignInFull(ctx, u, remember, true)
+	redirect := handleSignInFull(ctx, u, remember, true)
+	if ctx.Written() {
+		return
+	}
+	ctx.Redirect(redirect)
 }
 
 func handleSignInFull(ctx *context.Context, u *user_model.User, remember, obeyRedirect bool) string {
@@ -549,6 +569,12 @@ func handleSignInFull(ctx *context.Context, u *user_model.User, remember, obeyRe
 			setting.CookieRememberName, u.Name, days)
 	}
 
+	if _, err := session.RegenerateSession(ctx.Resp, ctx.Req); err != nil {
+		ctx.ServerError("RegenerateSession", err)
+		return setting.AppSubURL + "/"
+	}
+
+	// Delete the openid, 2fa and linkaccount data
 	_ = ctx.Session.Delete("openid_verified_uri")
 	_ = ctx.Session.Delete("openid_signin_remember")
 	_ = ctx.Session.Delete("openid_determined_email")
@@ -572,7 +598,7 @@ func handleSignInFull(ctx *context.Context, u *user_model.User, remember, obeyRe
 	if len(u.Language) == 0 {
 		u.Language = ctx.Locale.Language()
 		if err := user_model.UpdateUserCols(db.DefaultContext, u, "language"); err != nil {
-			log.Error(fmt.Sprintf("Error updating user language [user: %d, locale: %s]", u.ID, u.Language))
+			ctx.ServerError("UpdateUserCols Language", fmt.Errorf("Error updating user language [user: %d, locale: %s]", u.ID, u.Language))
 			return setting.AppSubURL + "/"
 		}
 	}
@@ -779,6 +805,11 @@ func getUserName(gothUser *goth.User) string {
 }
 
 func showLinkingLogin(ctx *context.Context, gothUser goth.User) {
+	if _, err := session.RegenerateSession(ctx.Resp, ctx.Req); err != nil {
+		ctx.ServerError("RegenerateSession", err)
+		return
+	}
+
 	if err := ctx.Session.Set("linkAccountGothUser", gothUser); err != nil {
 		log.Error("Error setting linkAccountGothUser in session: %v", err)
 	}
@@ -822,6 +853,12 @@ func handleOAuth2SignIn(ctx *context.Context, source *login.Source, u *user_mode
 	// If this user is enrolled in 2FA and this source doesn't override it,
 	// we can't sign the user in just yet. Instead, redirect them to the 2FA authentication page.
 	if !needs2FA {
+		if _, err := session.RegenerateSession(ctx.Resp, ctx.Req); err != nil {
+			ctx.ServerError("RegenerateSession", err)
+			return
+		}
+
+		// Set session IDs
 		if err := ctx.Session.Set("uid", u.ID); err != nil {
 			log.Error("Error setting uid in session: %v", err)
 		}
@@ -878,6 +915,11 @@ func handleOAuth2SignIn(ctx *context.Context, source *login.Source, u *user_mode
 		}
 	}
 
+	if _, err := session.RegenerateSession(ctx.Resp, ctx.Req); err != nil {
+		ctx.ServerError("RegenerateSession", err)
+		return
+	}
+
 	// User needs to use 2FA, save data and redirect to 2FA page.
 	if err := ctx.Session.Set("twofaUid", u.ID); err != nil {
 		log.Error("Error setting twofaUid in session: %v", err)
@@ -1090,6 +1132,11 @@ func linkAccount(ctx *context.Context, u *user_model.User, gothUser goth.User, r
 		return
 	}
 
+	if _, err := session.RegenerateSession(ctx.Resp, ctx.Req); err != nil {
+		ctx.ServerError("RegenerateSession", err)
+		return
+	}
+
 	// User needs to use 2FA, save data and redirect to 2FA page.
 	if err := ctx.Session.Set("twofaUid", u.ID); err != nil {
 		log.Error("Error setting twofaUid in session: %v", err)
@@ -1227,7 +1274,7 @@ func LinkAccountPostRegister(ctx *context.Context) {
 		return
 	}
 
-	ctx.Redirect(setting.AppSubURL + "/user/login")
+	handleSignIn(ctx, u, false)
 }
 
 // HandleSignOut resets the session and sets the cookies
@@ -1370,7 +1417,7 @@ func SignUpPost(ctx *context.Context) {
 	}
 
 	ctx.Flash.Success(ctx.Tr("auth.sign_up_successful"))
-	handleSignInFull(ctx, u, false, true)
+	handleSignIn(ctx, u, false)
 }
 
 // createAndHandleCreatedUser calls createUserInContext and
@@ -1591,6 +1638,13 @@ func handleAccountActivation(ctx *context.Context, user *user_model.User) {
 
 	log.Trace("User activated: %s", user.Name)
 
+	if _, err := session.RegenerateSession(ctx.Resp, ctx.Req); err != nil {
+		log.Error("Unable to regenerate session for user: %-v with email: %s: %v", user, user.Email, err)
+		ctx.ServerError("ActivateUserEmail", err)
+		return
+	}
+
+	// Set session IDs
 	if err := ctx.Session.Set("uid", user.ID); err != nil {
 		log.Error("Error setting uid in session[%s]: %v", ctx.Session.ID(), err)
 	}
@@ -1862,11 +1916,14 @@ func ResetPasswdPost(ctx *context.Context) {
 
 		handleSignInFull(ctx, u, remember, false)
 		ctx.Flash.Info(ctx.Tr("auth.twofa_scratch_used"))
+		if ctx.Written() {
+			return
+		}
 		ctx.Redirect(setting.AppSubURL + "/user/settings/security")
 		return
 	}
 
-	handleSignInFull(ctx, u, remember, true)
+	handleSignIn(ctx, u, remember)
 }
 
 // MustChangePassword renders the page to change a user's password
diff --git a/routers/web/user/auth_openid.go b/routers/web/user/auth_openid.go
index 884ec29c21..55dd8f8d09 100644
--- a/routers/web/user/auth_openid.go
+++ b/routers/web/user/auth_openid.go
@@ -16,6 +16,7 @@ import (
 	"code.gitea.io/gitea/modules/hcaptcha"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/recaptcha"
+	"code.gitea.io/gitea/modules/session"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/util"
 	"code.gitea.io/gitea/modules/web"
@@ -232,6 +233,11 @@ func signInOpenIDVerify(ctx *context.Context) {
 		}
 	}
 
+	if _, err := session.RegenerateSession(ctx.Resp, ctx.Req); err != nil {
+		ctx.ServerError("RegenerateSession", err)
+		return
+	}
+
 	if err := ctx.Session.Set("openid_verified_uri", id); err != nil {
 		log.Error("signInOpenIDVerify: Could not set openid_verified_uri in session: %v", err)
 	}
diff --git a/services/auth/auth.go b/services/auth/auth.go
index e53691221f..ceb9f4c5d8 100644
--- a/services/auth/auth.go
+++ b/services/auth/auth.go
@@ -15,6 +15,7 @@ import (
 	"code.gitea.io/gitea/models/db"
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/session"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/web/middleware"
 )
@@ -106,6 +107,14 @@ func isGitRawReleaseOrLFSPath(req *http.Request) bool {
 
 // handleSignIn clears existing session variables and stores new ones for the specified user object
 func handleSignIn(resp http.ResponseWriter, req *http.Request, sess SessionStore, user *user_model.User) {
+	// We need to regenerate the session...
+	newSess, err := session.RegenerateSession(resp, req)
+	if err != nil {
+		log.Error(fmt.Sprintf("Error regenerating session: %v", err))
+	} else {
+		sess = newSess
+	}
+
 	_ = sess.Delete("openid_verified_uri")
 	_ = sess.Delete("openid_signin_remember")
 	_ = sess.Delete("openid_determined_email")
@@ -114,7 +123,7 @@ func handleSignIn(resp http.ResponseWriter, req *http.Request, sess SessionStore
 	_ = sess.Delete("twofaRemember")
 	_ = sess.Delete("u2fChallenge")
 	_ = sess.Delete("linkAccount")
-	err := sess.Set("uid", user.ID)
+	err = sess.Set("uid", user.ID)
 	if err != nil {
 		log.Error(fmt.Sprintf("Error setting session: %v", err))
 	}
diff --git a/services/auth/source/oauth2/store.go b/services/auth/source/oauth2/store.go
index 4026abb6ec..f00264f997 100644
--- a/services/auth/source/oauth2/store.go
+++ b/services/auth/source/oauth2/store.go
@@ -55,6 +55,7 @@ func (st *SessionsStore) getOrNew(r *http.Request, name string, override bool) (
 		}
 	}
 
+	session.IsNew = override
 	session.ID = chiStore.ID() // Simply copy the session id from the chi store
 
 	return session, chiStore.Set(name, session)
@@ -64,6 +65,11 @@ func (st *SessionsStore) getOrNew(r *http.Request, name string, override bool) (
 func (st *SessionsStore) Save(r *http.Request, w http.ResponseWriter, session *sessions.Session) error {
 	chiStore := chiSession.GetSession(r)
 
+	if session.IsNew {
+		_, _ = chiSession.RegenerateSession(w, r)
+		session.IsNew = false
+	}
+
 	if err := chiStore.Set(session.Name(), session); err != nil {
 		return err
 	}
diff --git a/vendor/gitea.com/go-chi/session/session.go b/vendor/gitea.com/go-chi/session/session.go
index 5c2afedc93..be10674133 100644
--- a/vendor/gitea.com/go-chi/session/session.go
+++ b/vendor/gitea.com/go-chi/session/session.go
@@ -260,7 +260,7 @@ func Sessioner(options ...Options) func(next http.Handler) http.Handler {
 				return
 			}
 
-			if err = sess.Release(); err != nil {
+			if err = s.RawStore.Release(); err != nil {
 				panic("session(release): " + err.Error())
 			}
 		})
@@ -274,6 +274,26 @@ func GetSession(req *http.Request) Store {
 	return sess
 }
 
+// RegenerateSession
+func RegenerateSession(resp http.ResponseWriter, req *http.Request) (Store, error) {
+	sess, ok := GetSession(req).(*store)
+	if !ok {
+		return nil, fmt.Errorf("no session in request context")
+	}
+
+	oldRawStore := sess.RawStore
+	if err := oldRawStore.Release(); err != nil {
+		return nil, err
+	}
+
+	store, err := sess.RegenerateID(resp, req)
+	if err != nil {
+		return nil, err
+	}
+	sess.RawStore = store
+	return sess, nil
+}
+
 // Provider is the interface that provides session manipulations.
 type Provider interface {
 	// Init initializes session provider.
diff --git a/vendor/modules.txt b/vendor/modules.txt
index 20444be1cf..8b2b9350b7 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -18,7 +18,7 @@ gitea.com/go-chi/cache/memcache
 # gitea.com/go-chi/captcha v0.0.0-20211013065431-70641c1a35d5
 ## explicit
 gitea.com/go-chi/captcha
-# gitea.com/go-chi/session v0.0.0-20211013065435-7d334f340c09
+# gitea.com/go-chi/session v0.0.0-20211218221615-e3605d8b28b8
 ## explicit
 gitea.com/go-chi/session
 gitea.com/go-chi/session/couchbase