tailscale/safeweb/http_test.go
Andrew Lytvynov ddbc950f46
safeweb: add support for custom CSP (#13975)
To allow more flexibility with CSPs, add a fully customizable `CSP` type
that can be provided in `Config` and encodes itself into the correct
format. Preserve the `CSPAllowInlineStyles` option as is today, but
maybe that'll get deprecated later in favor of the new CSP field.

In particular, this allows for pages loading external JS, or inline JS
with nonces or hashes (see
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/script-src#unsafe_inline_script)

Updates https://github.com/tailscale/corp/issues/8027

Signed-off-by: Andrew Lytvynov <awly@tailscale.com>
2024-10-31 12:13:29 -07:00

650 lines
16 KiB
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
package safeweb
import (
"io"
"net/http"
"net/http/httptest"
"strconv"
"strings"
"testing"
"time"
"github.com/google/go-cmp/cmp"
"github.com/gorilla/csrf"
)
func TestCompleteCORSConfig(t *testing.T) {
_, err := NewServer(Config{AccessControlAllowOrigin: []string{"https://foobar.com"}})
if err == nil {
t.Fatalf("expected error when AccessControlAllowOrigin is provided without AccessControlAllowMethods")
}
_, err = NewServer(Config{AccessControlAllowMethods: []string{"GET", "POST"}})
if err == nil {
t.Fatalf("expected error when AccessControlAllowMethods is provided without AccessControlAllowOrigin")
}
_, err = NewServer(Config{AccessControlAllowOrigin: []string{"https://foobar.com"}, AccessControlAllowMethods: []string{"GET", "POST"}})
if err != nil {
t.Fatalf("error creating server with complete CORS configuration: %v", err)
}
}
func TestPostRequestContentTypeValidation(t *testing.T) {
tests := []struct {
name string
browserRoute bool
contentType string
wantErr bool
}{
{
name: "API routes should accept `application/json` content-type",
browserRoute: false,
contentType: "application/json",
wantErr: false,
},
{
name: "API routes should reject `application/x-www-form-urlencoded` content-type",
browserRoute: false,
contentType: "application/x-www-form-urlencoded",
wantErr: true,
},
{
name: "Browser routes should accept `application/x-www-form-urlencoded` content-type",
browserRoute: true,
contentType: "application/x-www-form-urlencoded",
wantErr: false,
},
{
name: "non Browser routes should accept `application/json` content-type",
browserRoute: true,
contentType: "application/json",
wantErr: false,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
h := &http.ServeMux{}
h.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("ok"))
}))
var s *Server
var err error
if tt.browserRoute {
s, err = NewServer(Config{BrowserMux: h})
} else {
s, err = NewServer(Config{APIMux: h})
}
if err != nil {
t.Fatal(err)
}
defer s.Close()
req := httptest.NewRequest("POST", "/", nil)
req.Header.Set("Content-Type", tt.contentType)
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, req)
resp := w.Result()
if tt.wantErr && resp.StatusCode != http.StatusBadRequest {
t.Fatalf("content type validation failed: got %v; want %v", resp.StatusCode, http.StatusBadRequest)
}
})
}
}
func TestAPIMuxCrossOriginResourceSharingHeaders(t *testing.T) {
tests := []struct {
name string
httpMethod string
wantCORSHeaders bool
corsOrigins []string
corsMethods []string
}{
{
name: "do not set CORS headers for non-OPTIONS requests",
corsOrigins: []string{"https://foobar.com"},
corsMethods: []string{"GET", "POST", "HEAD"},
httpMethod: "GET",
wantCORSHeaders: false,
},
{
name: "set CORS headers for non-OPTIONS requests",
corsOrigins: []string{"https://foobar.com"},
corsMethods: []string{"GET", "POST", "HEAD"},
httpMethod: "OPTIONS",
wantCORSHeaders: true,
},
{
name: "do not serve CORS headers for OPTIONS requests with no configured origins",
httpMethod: "OPTIONS",
wantCORSHeaders: false,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
h := &http.ServeMux{}
h.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("ok"))
}))
s, err := NewServer(Config{
APIMux: h,
AccessControlAllowOrigin: tt.corsOrigins,
AccessControlAllowMethods: tt.corsMethods,
})
if err != nil {
t.Fatal(err)
}
defer s.Close()
req := httptest.NewRequest(tt.httpMethod, "/", nil)
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, req)
resp := w.Result()
if (resp.Header.Get("Access-Control-Allow-Origin") == "") == tt.wantCORSHeaders {
t.Fatalf("access-control-allow-origin want: %v; got: %v", tt.wantCORSHeaders, resp.Header.Get("Access-Control-Allow-Origin"))
}
})
}
}
func TestCSRFProtection(t *testing.T) {
tests := []struct {
name string
apiRoute bool
passCSRFToken bool
wantStatus int
}{
{
name: "POST requests to non-API routes require CSRF token and fail if not provided",
apiRoute: false,
passCSRFToken: false,
wantStatus: http.StatusForbidden,
},
{
name: "POST requests to non-API routes require CSRF token and pass if provided",
apiRoute: false,
passCSRFToken: true,
wantStatus: http.StatusOK,
},
{
name: "POST requests to /api/ routes do not require CSRF token",
apiRoute: true,
passCSRFToken: false,
wantStatus: http.StatusOK,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
h := &http.ServeMux{}
h.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("ok"))
}))
var s *Server
var err error
if tt.apiRoute {
s, err = NewServer(Config{APIMux: h})
} else {
s, err = NewServer(Config{BrowserMux: h})
}
if err != nil {
t.Fatal(err)
}
defer s.Close()
// construct the test request
req := httptest.NewRequest("POST", "/", nil)
// send JSON for API routes, form data for browser routes
if tt.apiRoute {
req.Header.Set("Content-Type", "application/json")
} else {
req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
}
// retrieve CSRF cookie & pass it in the test request
// ref: https://github.com/gorilla/csrf/blob/main/csrf_test.go#L344-L347
var token string
if tt.passCSRFToken {
h.Handle("/csrf", http.HandlerFunc(func(_ http.ResponseWriter, r *http.Request) {
token = csrf.Token(r)
}))
get := httptest.NewRequest("GET", "/csrf", nil)
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, get)
resp := w.Result()
// pass the token & cookie in our subsequent test request
req.Header.Set("X-CSRF-Token", token)
for _, c := range resp.Cookies() {
req.AddCookie(c)
}
}
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, req)
resp := w.Result()
if resp.StatusCode != tt.wantStatus {
t.Fatalf("csrf protection check failed: got %v; want %v", resp.StatusCode, tt.wantStatus)
}
})
}
}
func TestContentSecurityPolicyHeader(t *testing.T) {
tests := []struct {
name string
csp CSP
apiRoute bool
wantCSP string
}{
{
name: "default CSP",
wantCSP: `base-uri 'self'; block-all-mixed-content; default-src 'self'; form-action 'self'; frame-ancestors 'none';`,
},
{
name: "custom CSP",
csp: CSP{
"default-src": {"'self'", "https://tailscale.com"},
"upgrade-insecure-requests": nil,
},
wantCSP: `default-src 'self' https://tailscale.com; upgrade-insecure-requests;`,
},
{
name: "`/api/*` routes do not get CSP headers",
apiRoute: true,
wantCSP: "",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
h := &http.ServeMux{}
h.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("ok"))
}))
var s *Server
var err error
if tt.apiRoute {
s, err = NewServer(Config{APIMux: h, CSP: tt.csp})
} else {
s, err = NewServer(Config{BrowserMux: h, CSP: tt.csp})
}
if err != nil {
t.Fatal(err)
}
defer s.Close()
req := httptest.NewRequest("GET", "/", nil)
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, req)
resp := w.Result()
if got := resp.Header.Get("Content-Security-Policy"); got != tt.wantCSP {
t.Fatalf("content security policy want: %q; got: %q", tt.wantCSP, got)
}
})
}
}
func TestCSRFCookieSecureMode(t *testing.T) {
tests := []struct {
name string
secureMode bool
wantSecure bool
}{
{
name: "CSRF cookie should be secure when server is in secure context",
secureMode: true,
wantSecure: true,
},
{
name: "CSRF cookie should not be secure when server is not in secure context",
secureMode: false,
wantSecure: false,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
h := &http.ServeMux{}
h.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("ok"))
}))
s, err := NewServer(Config{BrowserMux: h, SecureContext: tt.secureMode})
if err != nil {
t.Fatal(err)
}
defer s.Close()
req := httptest.NewRequest("GET", "/", nil)
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, req)
resp := w.Result()
cookie := resp.Cookies()[0]
if (cookie.Secure == tt.wantSecure) == false {
t.Fatalf("csrf cookie secure flag want: %v; got: %v", tt.wantSecure, cookie.Secure)
}
})
}
}
func TestRefererPolicy(t *testing.T) {
tests := []struct {
name string
browserRoute bool
wantRefererPolicy bool
}{
{
name: "BrowserMux routes get Referer-Policy headers",
browserRoute: true,
wantRefererPolicy: true,
},
{
name: "APIMux routes do not get Referer-Policy headers",
browserRoute: false,
wantRefererPolicy: false,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
h := &http.ServeMux{}
h.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("ok"))
}))
var s *Server
var err error
if tt.browserRoute {
s, err = NewServer(Config{BrowserMux: h})
} else {
s, err = NewServer(Config{APIMux: h})
}
if err != nil {
t.Fatal(err)
}
defer s.Close()
req := httptest.NewRequest("GET", "/", nil)
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, req)
resp := w.Result()
if (resp.Header.Get("Referer-Policy") == "") == tt.wantRefererPolicy {
t.Fatalf("referer policy want: %v; got: %v", tt.wantRefererPolicy, resp.Header.Get("Referer-Policy"))
}
})
}
}
func TestCSPAllowInlineStyles(t *testing.T) {
for _, allow := range []bool{false, true} {
t.Run(strconv.FormatBool(allow), func(t *testing.T) {
h := &http.ServeMux{}
h.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("ok"))
}))
s, err := NewServer(Config{BrowserMux: h, CSPAllowInlineStyles: allow})
if err != nil {
t.Fatal(err)
}
defer s.Close()
req := httptest.NewRequest("GET", "/", nil)
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, req)
resp := w.Result()
csp := resp.Header.Get("Content-Security-Policy")
allowsStyles := strings.Contains(csp, "style-src 'self' 'unsafe-inline'")
if allowsStyles != allow {
t.Fatalf("CSP inline styles want: %v, got: %v in %q", allow, allowsStyles, csp)
}
})
}
}
func TestRouting(t *testing.T) {
for _, tt := range []struct {
desc string
browserPatterns []string
apiPatterns []string
requestPath string
want string
}{
{
desc: "only browser mux",
browserPatterns: []string{"/"},
requestPath: "/index.html",
want: "browser",
},
{
desc: "only API mux",
apiPatterns: []string{"/api/"},
requestPath: "/api/foo",
want: "api",
},
{
desc: "browser mux match",
browserPatterns: []string{"/content/"},
apiPatterns: []string{"/api/"},
requestPath: "/content/index.html",
want: "browser",
},
{
desc: "API mux match",
browserPatterns: []string{"/content/"},
apiPatterns: []string{"/api/"},
requestPath: "/api/foo",
want: "api",
},
{
desc: "browser wildcard match",
browserPatterns: []string{"/"},
apiPatterns: []string{"/api/"},
requestPath: "/index.html",
want: "browser",
},
{
desc: "API wildcard match",
browserPatterns: []string{"/content/"},
apiPatterns: []string{"/"},
requestPath: "/api/foo",
want: "api",
},
{
desc: "path conflict",
browserPatterns: []string{"/foo/"},
apiPatterns: []string{"/foo/bar/"},
requestPath: "/foo/bar/baz",
want: "api",
},
{
desc: "no match",
browserPatterns: []string{"/foo/"},
apiPatterns: []string{"/bar/"},
requestPath: "/baz",
want: "404 page not found",
},
} {
t.Run(tt.desc, func(t *testing.T) {
bm := &http.ServeMux{}
for _, p := range tt.browserPatterns {
bm.HandleFunc(p, func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("browser"))
})
}
am := &http.ServeMux{}
for _, p := range tt.apiPatterns {
am.HandleFunc(p, func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("api"))
})
}
s, err := NewServer(Config{BrowserMux: bm, APIMux: am})
if err != nil {
t.Fatal(err)
}
defer s.Close()
req := httptest.NewRequest("GET", tt.requestPath, nil)
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, req)
resp, err := io.ReadAll(w.Result().Body)
if err != nil {
t.Fatal(err)
}
if got := strings.TrimSpace(string(resp)); got != tt.want {
t.Errorf("got response %q, want %q", got, tt.want)
}
})
}
}
func TestGetMoreSpecificPattern(t *testing.T) {
for _, tt := range []struct {
desc string
a string
b string
want handlerType
}{
{
desc: "identical",
a: "/foo/bar",
b: "/foo/bar",
want: unknownHandler,
},
{
desc: "identical prefix",
a: "/foo/bar/",
b: "/foo/bar/",
want: unknownHandler,
},
{
desc: "trailing slash",
a: "/foo",
b: "/foo/", // path.Clean will strip the trailing slash.
want: unknownHandler,
},
{
desc: "same prefix",
a: "/foo/bar/quux",
b: "/foo/bar/", // path.Clean will strip the trailing slash.
want: apiHandler,
},
{
desc: "almost same prefix, but not a path component",
a: "/goat/sheep/cheese",
b: "/goat/sheepcheese/", // path.Clean will strip the trailing slash.
want: apiHandler,
},
{
desc: "attempt to make less-specific pattern look more specific",
a: "/goat/cat/buddy",
b: "/goat/../../../../../../../cat", // path.Clean catches this foolishness
want: apiHandler,
},
{
desc: "2 names for / (1)",
a: "/",
b: "/../../../../../../",
want: unknownHandler,
},
{
desc: "2 names for / (2)",
a: "/",
b: "///////",
want: unknownHandler,
},
{
desc: "root-level",
a: "/latest",
b: "/", // path.Clean will NOT strip the trailing slash.
want: apiHandler,
},
} {
t.Run(tt.desc, func(t *testing.T) {
got := checkHandlerType(tt.a, tt.b)
if got != tt.want {
t.Errorf("got %q, want %q", got, tt.want)
}
})
}
}
func TestStrictTransportSecurityOptions(t *testing.T) {
tests := []struct {
name string
options string
secureContext bool
expect string
}{
{
name: "off by default",
},
{
name: "default HSTS options in the secure context",
secureContext: true,
expect: DefaultStrictTransportSecurityOptions,
},
{
name: "custom options sent in the secure context",
options: DefaultStrictTransportSecurityOptions + "; includeSubDomains",
secureContext: true,
expect: DefaultStrictTransportSecurityOptions + "; includeSubDomains",
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
h := &http.ServeMux{}
h.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Write([]byte("ok"))
}))
s, err := NewServer(Config{BrowserMux: h, SecureContext: tt.secureContext, StrictTransportSecurityOptions: tt.options})
if err != nil {
t.Fatal(err)
}
defer s.Close()
req := httptest.NewRequest("GET", "/", nil)
w := httptest.NewRecorder()
s.h.Handler.ServeHTTP(w, req)
resp := w.Result()
if cmp.Diff(tt.expect, resp.Header.Get("Strict-Transport-Security")) != "" {
t.Fatalf("HSTS want: %q; got: %q", tt.expect, resp.Header.Get("Strict-Transport-Security"))
}
})
}
}
func TestOverrideHTTPServer(t *testing.T) {
s, err := NewServer(Config{})
if err != nil {
t.Fatalf("NewServer: %v", err)
}
if s.h.IdleTimeout != 0 {
t.Fatalf("got %v; want 0", s.h.IdleTimeout)
}
c := http.Server{
IdleTimeout: 10 * time.Second,
}
s, err = NewServer(Config{HTTPServer: &c})
if err != nil {
t.Fatalf("NewServer: %v", err)
}
if s.h.IdleTimeout != c.IdleTimeout {
t.Fatalf("got %v; want %v", s.h.IdleTimeout, c.IdleTimeout)
}
}