ff761d2 · typeable/oauth2-proxy

git.iko.soy/typeable/oauth2-proxy

fix: runtime error: index out of range (0) with length 0 (#2328)

* Issue 2311: runtime error: index out of range [0] with length 0 while extracting state of of the csrf --------- Co-authored-by: tuunit <jan@larwig.com>

commitff761d2523c2b4e1fd291b8833e667bb65b41de5 authorNuno Miguel Micaelo Borges <miguelborges99@gmail.com> dateTue 8 Oct 2024, 13:40 (2 years ago) parent642ba17

4 files changed+54−28

compare with master

unifiedsplit

CHANGELOG.md+1 oauthproxy.go+39−9 pkg/cookies/csrf.go+8−15 pkg/cookies/csrf_test.go+6−4

CHANGELOG.md+1

@@ -10,6 +10,7 @@

1010

1111- [#2803](https://github.com/oauth2-proxy/oauth2-proxy/pull/2803) fix: self signed certificate handling in v7.7.0 (@tuunit)

1212- [#2619](https://github.com/oauth2-proxy/oauth2-proxy/pull/2619) fix: unable to use hyphen in JSON path for oidc-groups-claim option (@rd-danny-fleer)

13+- [#2311](https://github.com/oauth2-proxy/oauth2-proxy/pull/2311) fix: runtime error: index out of range (0) with length 0 (@miguelborges99 / @tuunit)

1314

1415# V7.7.0

1516

oauthproxy.go+39−9

@@ -870,9 +870,22 @@ func (p *OAuthProxy) OAuthCallback(rw http.ResponseWriter, req *http.Request) {

870870 return

871871 }

872872

873− csrf, err := cookies.LoadCSRFCookie(req, p.CookieOptions)

873+ nonce, appRedirect, err := decodeState(req.Form.Get("state"), p.encodeState)

874+ if err != nil {

875+ logger.Errorf("Error while parsing OAuth2 state: %v", err)

876+ p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())

877+ return

878+ }

879+

880+ // calculate the cookie name

881+ cookieName := cookies.GenerateCookieName(p.CookieOptions, nonce)

882+ // Try to find the CSRF cookie and decode it

883+ csrf, err := cookies.LoadCSRFCookie(req, cookieName, p.CookieOptions)

874884 if err != nil {

875− logger.Println(req, logger.AuthFailure, "Invalid authentication via OAuth2. Error while loading CSRF cookie:", err.Error())

885+ // There are a lot of issues opened complaining about missing CSRF cookies.

886+ // Try to log the INs and OUTs of OAuthProxy, to be easier to analyse these issues.

887+ LoggingCSRFCookiesInOAuthCallback(req, cookieName)

888+ logger.Println(req, logger.AuthFailure, "Invalid authentication via OAuth2: unable to obtain CSRF cookie: %s (state=%s)", err, nonce)

876889 p.ErrorPage(rw, req, http.StatusForbidden, err.Error(), "Login Failed: Unable to find a valid CSRF token. Please try again.")

877890 return

878891 }

@@ -893,13 +906,6 @@ func (p *OAuthProxy) OAuthCallback(rw http.ResponseWriter, req *http.Request) {

893906

894907 csrf.ClearCookie(rw, req)

895908

896− nonce, appRedirect, err := decodeState(req.Form.Get("state"), p.encodeState)

897− if err != nil {

898− logger.Errorf("Error while parsing OAuth2 state: %v", err)

899− p.ErrorPage(rw, req, http.StatusInternalServerError, err.Error())

900− return

901− }

902−

903909 if !csrf.CheckOAuthState(nonce) {

904910 logger.PrintAuthf(session.Email, req, logger.AuthFailure, "Invalid authentication via OAuth2: CSRF token mismatch, potential attack")

905911 p.ErrorPage(rw, req, http.StatusForbidden, "CSRF token mismatch, potential attack", "Login Failed: Unable to find a valid CSRF token. Please try again.")

@@ -1297,3 +1303,27 @@ func (p *OAuthProxy) errorJSON(rw http.ResponseWriter, code int) {

12971303 // application/json

12981304 rw.Write([]byte("{}"))

12991305}

1306+

1307+// LoggingCSRFCookiesInOAuthCallback Log all CSRF cookies found in HTTP request OAuth callback,

1308+// which were successfully parsed

1309+func LoggingCSRFCookiesInOAuthCallback(req *http.Request, cookieName string) {

1310+ cookies := req.Cookies()

1311+ if len(cookies) == 0 {

1312+ logger.Println(req, logger.AuthFailure, "No cookies were found in OAuth callback.")

1313+ return

1314+ }

1315+

1316+ for _, c := range cookies {

1317+ if cookieName == c.Name {

1318+ logger.Println(req, logger.AuthFailure, "CSRF cookie %s was found in OAuth callback.", c.Name)

1319+ return

1320+ }

1321+

1322+ if strings.HasSuffix(c.Name, "_csrf") {

1323+ logger.Println(req, logger.AuthFailure, "CSRF cookie %s was found in OAuth callback, but it is not the expected one (%s).", c.Name, cookieName)

1324+ return

1325+ }

1326+ }

1327+

1328+ logger.Println(req, logger.AuthFailure, "Cookies were found in OAuth callback, but none was a CSRF cookie.")

1329+}

pkg/cookies/csrf.go+8−15

@@ -72,9 +72,7 @@ func NewCSRF(opts *options.Cookie, codeVerifier string) (CSRF, error) {

7272}

7373

7474// LoadCSRFCookie loads a CSRF object from a request's CSRF cookie

75−func LoadCSRFCookie(req *http.Request, opts *options.Cookie) (CSRF, error) {

76− cookieName := GenerateCookieName(req, opts)

77−

75+func LoadCSRFCookie(req *http.Request, cookieName string, opts *options.Cookie) (CSRF, error) {

7876 cookies := req.Cookies()

7977 for _, cookie := range cookies {

8078 if cookie.Name != cookieName {

@@ -89,17 +87,17 @@ func LoadCSRFCookie(req *http.Request, opts *options.Cookie) (CSRF, error) {

8987 return csrf, nil

9088 }

9189

92− return nil, errors.New("CSRF cookie not found")

90+ return nil, fmt.Errorf("CSRF cookie with name '%v' was not found", cookieName)

9391}

9492

9593// GenerateCookieName in case cookie options state that CSRF cookie has fixed name then set fixed name, otherwise

9694// build name based on the state

97−func GenerateCookieName(req *http.Request, opts *options.Cookie) string {

95+func GenerateCookieName(opts *options.Cookie, state string) string {

9896 stateSubstring := ""

9997 if opts.CSRFPerRequest {

10098 // csrfCookieName will include a substring of the state to enable multiple csrf cookies

10199 // in case of parallel requests

102− stateSubstring = ExtractStateSubstring(req)

100+ stateSubstring = ExtractStateSubstring(state)

103101 }

104102 return csrfCookieName(opts, stateSubstring)

105103}

@@ -218,20 +216,15 @@ func csrfCookieName(opts *options.Cookie, stateSubstring string) string {

218216 if stateSubstring == "" {

219217 return fmt.Sprintf("%v_csrf", opts.Name)

220218 }

221− return fmt.Sprintf("%v_csrf_%v", opts.Name, stateSubstring)

219+ return fmt.Sprintf("%v_%v_csrf", opts.Name, stateSubstring)

222220}

223221

224222// ExtractStateSubstring extract the initial state characters, to add it to the CSRF cookie name

225−func ExtractStateSubstring(req *http.Request) string {

223+func ExtractStateSubstring(state string) string {

226224 lastChar := csrfStateLength - 1

227225 stateSubstring := ""

228−

229− state := req.URL.Query()["state"]

230− if state[0] != "" {

231− state := state[0]

232− if lastChar <= len(state) {

233− stateSubstring = state[0:lastChar]

234− }

226+ if lastChar <= len(state) {

227+ stateSubstring = state[0:lastChar]

235228 }

236229 return stateSubstring

237230}

pkg/cookies/csrf_test.go+6−4

@@ -19,6 +19,7 @@ var _ = Describe("CSRF Cookie Tests", func() {

1919 cookieOpts *options.Cookie

2020 publicCSRF CSRF

2121 privateCSRF *csrf

22+ csrfName string

2223 )

2324

2425 BeforeEach(func() {

@@ -39,6 +40,7 @@ var _ = Describe("CSRF Cookie Tests", func() {

3940 Expect(err).ToNot(HaveOccurred())

4041

4142 privateCSRF = publicCSRF.(*csrf)

43+ csrfName = GenerateCookieName(cookieOpts, csrfNonce)

4244 })

4345

4446 Context("NewCSRF", func() {

@@ -175,7 +177,7 @@ var _ = Describe("CSRF Cookie Tests", func() {

175177 })

176178

177179 It("should return error when no cookie is set", func() {

178− csrf, err := LoadCSRFCookie(req, cookieOpts)

180+ csrf, err := LoadCSRFCookie(req, csrfName, cookieOpts)

179181 Expect(err).To(HaveOccurred())

180182 Expect(csrf).To(BeNil())

181183 })

@@ -191,7 +193,7 @@ var _ = Describe("CSRF Cookie Tests", func() {

191193 Value: encoded,

192194 })

193195

194− csrf, err := LoadCSRFCookie(req, cookieOpts)

196+ csrf, err := LoadCSRFCookie(req, csrfName, cookieOpts)

195197 Expect(err).ToNot(HaveOccurred())

196198 Expect(csrf).ToNot(BeNil())

197199 })

@@ -202,7 +204,7 @@ var _ = Describe("CSRF Cookie Tests", func() {

202204 Value: "invalid",

203205 })

204206

205− csrf, err := LoadCSRFCookie(req, cookieOpts)

207+ csrf, err := LoadCSRFCookie(req, csrfName, cookieOpts)

206208 Expect(err).To(HaveOccurred())

207209 Expect(csrf).To(BeNil())

208210 })

@@ -223,7 +225,7 @@ var _ = Describe("CSRF Cookie Tests", func() {

223225 Value: encoded,

224226 })

225227

226− csrf, err := LoadCSRFCookie(req, cookieOpts)

228+ csrf, err := LoadCSRFCookie(req, csrfName, cookieOpts)

227229 Expect(err).ToNot(HaveOccurred())

228230 Expect(csrf).ToNot(BeNil())

229231 })