internal/sessions: refactor how sessions loading (#351)

These chagnes standardize how session loading is done for session
cookie, auth bearer token, and query params.

- Bearer token previously combined with session cookie.
- rearranged cookie-store to put exported methods above unexported
- added header store that implements session loader interface
- added query param store that implements session loader interface

Signed-off-by: Bobby DeSimone <bobbydesimone@gmail.com>

internal/sessions/cookie_store.go

@@ -10,47 +10,39 @@ import (
 	"github.com/pomerium/pomerium/internal/cryptutil"
 )
 
-// ChunkedCanaryByte is the byte value used as a canary prefix to distinguish if
-// the cookie is multi-part or not. This constant *should not* be valid
-// base64. It's important this byte is ASCII to avoid UTF-8 variable sized runes.
-// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Set-Cookie#Directives
-const ChunkedCanaryByte byte = '%'
+const (
+	// ChunkedCanaryByte is the byte value used as a canary prefix to distinguish if
+	// the cookie is multi-part or not. This constant *should not* be valid
+	// base64. It's important this byte is ASCII to avoid UTF-8 variable sized runes.
+	// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Set-Cookie#Directives
+	ChunkedCanaryByte byte = '%'
+	// MaxChunkSize sets the upper bound on a cookie chunks payload value.
+	// Note, this should be lower than the actual cookie's max size (4096 bytes)
+	// which includes metadata.
+	MaxChunkSize = 3800
+	// MaxNumChunks limits the number of chunks to iterate through. Conservatively
+	// set to prevent any abuse.
+	MaxNumChunks = 5
+)
 
-// DefaultBearerTokenHeader is default header name for the authorization bearer
-// token header as defined in rfc2617
-// https://tools.ietf.org/html/rfc6750#section-2.1
-const DefaultBearerTokenHeader = "Authorization"
-
-// MaxChunkSize sets the upper bound on a cookie chunks payload value.
-// Note, this should be lower than the actual cookie's max size (4096 bytes)
-// which includes metadata.
-const MaxChunkSize = 3800
-
-// MaxNumChunks limits the number of chunks to iterate through. Conservatively
-// set to prevent any abuse.
-const MaxNumChunks = 5
-
-// CookieStore represents all the cookie related configurations
+// CookieStore implements the session store interface for session cookies.
 type CookieStore struct {
-	Name              string
-	Encoder           cryptutil.SecureEncoder
-	CookieExpire      time.Duration
-	CookieRefresh     time.Duration
-	CookieSecure      bool
-	CookieHTTPOnly    bool
-	CookieDomain      string
-	BearerTokenHeader string
+	Name           string
+	CookieDomain   string
+	CookieExpire   time.Duration
+	CookieHTTPOnly bool
+	CookieSecure   bool
+	Encoder        cryptutil.SecureEncoder
 }
 
 // CookieStoreOptions holds options for CookieStore
 type CookieStoreOptions struct {
-	Name              string
-	CookieSecure      bool
-	CookieHTTPOnly    bool
-	CookieDomain      string
-	BearerTokenHeader string
-	CookieExpire      time.Duration
-	Encoder           cryptutil.SecureEncoder
+	Name           string
+	CookieDomain   string
+	CookieExpire   time.Duration
+	CookieHTTPOnly bool
+	CookieSecure   bool
+	Encoder        cryptutil.SecureEncoder
 }
 
 // NewCookieStore returns a new session with ciphers for each of the cookie secrets
@@ -61,18 +53,14 @@ func NewCookieStore(opts *CookieStoreOptions) (*CookieStore, error) {
 	if opts.Encoder == nil {
 		return nil, fmt.Errorf("internal/sessions: cipher cannot be nil")
 	}
-	if opts.BearerTokenHeader == "" {
-		opts.BearerTokenHeader = DefaultBearerTokenHeader
-	}
 
 	return &CookieStore{
-		Name:              opts.Name,
-		CookieSecure:      opts.CookieSecure,
-		CookieHTTPOnly:    opts.CookieHTTPOnly,
-		CookieDomain:      opts.CookieDomain,
-		CookieExpire:      opts.CookieExpire,
-		Encoder:           opts.Encoder,
-		BearerTokenHeader: opts.BearerTokenHeader,
+		Name:           opts.Name,
+		CookieSecure:   opts.CookieSecure,
+		CookieHTTPOnly: opts.CookieHTTPOnly,
+		CookieDomain:   opts.CookieDomain,
+		CookieExpire:   opts.CookieExpire,
+		Encoder:        opts.Encoder,
 	}, nil
 }
 
@@ -103,11 +91,43 @@ func (cs *CookieStore) makeCookie(req *http.Request, name string, value string,
 	return c
 }
 
+// ClearSession clears the session cookie from a request
+func (cs *CookieStore) ClearSession(w http.ResponseWriter, req *http.Request) {
+	http.SetCookie(w, cs.makeCookie(req, cs.Name, "", time.Hour*-1, time.Now()))
+}
+
+// LoadSession returns a State from the cookie in the request.
+func (cs *CookieStore) LoadSession(req *http.Request) (*State, error) {
+	cipherText := loadChunkedCookie(req, cs.Name)
+	if cipherText == "" {
+		return nil, ErrNoSessionFound
+	}
+	session, err := UnmarshalSession(cipherText, cs.Encoder)
+	if err != nil {
+		return nil, ErrMalformed
+	}
+	return session, nil
+}
+
+// SaveSession saves a session state to a request sessions.
+func (cs *CookieStore) SaveSession(w http.ResponseWriter, req *http.Request, s *State) error {
+	value, err := MarshalSession(s, cs.Encoder)
+	if err != nil {
+		return err
+	}
+	cs.setSessionCookie(w, req, value)
+	return nil
+}
+
 // makeSessionCookie constructs a session cookie given the request, an expiration time and the current time.
 func (cs *CookieStore) makeSessionCookie(req *http.Request, value string, expiration time.Duration, now time.Time) *http.Cookie {
 	return cs.makeCookie(req, cs.Name, value, expiration, now)
 }
 
+func (cs *CookieStore) setSessionCookie(w http.ResponseWriter, req *http.Request, val string) {
+	cs.setCookie(w, cs.makeSessionCookie(req, val, cs.CookieExpire, time.Now()))
+}
+
 func (cs *CookieStore) setCookie(w http.ResponseWriter, cookie *http.Cookie) {
 	if len(cookie.String()) <= MaxChunkSize {
 		http.SetCookie(w, cookie)
@@ -128,35 +148,6 @@ func (cs *CookieStore) setCookie(w http.ResponseWriter, cookie *http.Cookie) {
 	}
 }
 
-func chunk(s string, size int) []string {
-	ss := make([]string, 0, len(s)/size+1)
-	for len(s) > 0 {
-		if len(s) < size {
-			size = len(s)
-		}
-		ss, s = append(ss, s[:size]), s[size:]
-	}
-	return ss
-}
-
-// ClearSession clears the session cookie from a request
-func (cs *CookieStore) ClearSession(w http.ResponseWriter, req *http.Request) {
-	http.SetCookie(w, cs.makeCookie(req, cs.Name, "", time.Hour*-1, time.Now()))
-}
-
-func (cs *CookieStore) setSessionCookie(w http.ResponseWriter, req *http.Request, val string) {
-	cs.setCookie(w, cs.makeSessionCookie(req, val, cs.CookieExpire, time.Now()))
-}
-
-func loadBearerToken(r *http.Request, headerKey string) string {
-	authHeader := r.Header.Get(headerKey)
-	split := strings.Split(authHeader, "Bearer")
-	if authHeader == "" || len(split) != 2 {
-		return ""
-	}
-	return strings.TrimSpace(split[1])
-}
-
 func loadChunkedCookie(r *http.Request, cookieName string) string {
 	c, err := r.Cookie(cookieName)
 	if err != nil {
@@ -179,37 +170,13 @@ func loadChunkedCookie(r *http.Request, cookieName string) string {
 	return cipherText
 }
 
-// LoadSession returns a State from the cookie in the request.
-func (cs *CookieStore) LoadSession(req *http.Request) (*State, error) {
-	cipherText := loadChunkedCookie(req, cs.Name)
-	if cipherText == "" {
-		cipherText = loadBearerToken(req, cs.BearerTokenHeader)
+func chunk(s string, size int) []string {
+	ss := make([]string, 0, len(s)/size+1)
+	for len(s) > 0 {
+		if len(s) < size {
+			size = len(s)
+		}
+		ss, s = append(ss, s[:size]), s[size:]
 	}
-	if cipherText == "" {
-		return nil, ErrEmptySession
-	}
-	session, err := UnmarshalSession(cipherText, cs.Encoder)
-	if err != nil {
-		return nil, err
-	}
-	return session, nil
-}
-
-// SaveSession saves a session state to a request sessions.
-func (cs *CookieStore) SaveSession(w http.ResponseWriter, req *http.Request, s *State) error {
-	value, err := MarshalSession(s, cs.Encoder)
-	if err != nil {
-		return err
-	}
-	cs.setSessionCookie(w, req, value)
-	return nil
-}
-
-// ParentSubdomain returns the parent subdomain.
-func ParentSubdomain(s string) string {
-	if strings.Count(s, ".") < 2 {
-		return ""
-	}
-	split := strings.SplitN(s, ".", 2)
-	return split[1]
+	return ss
 }

internal/sessions/cookie_store_test.go

@@ -38,33 +38,30 @@ func TestNewCookieStore(t *testing.T) {
 	}{
 		{"good",
 			&CookieStoreOptions{
-				Name:              "_cookie",
-				CookieSecure:      true,
-				CookieHTTPOnly:    true,
-				CookieDomain:      "pomerium.io",
-				CookieExpire:      10 * time.Second,
-				Encoder:           encoder,
-				BearerTokenHeader: "Authorization",
+				Name:           "_cookie",
+				CookieSecure:   true,
+				CookieHTTPOnly: true,
+				CookieDomain:   "pomerium.io",
+				CookieExpire:   10 * time.Second,
+				Encoder:        encoder,
 			},
 			&CookieStore{
-				Name:              "_cookie",
-				CookieSecure:      true,
-				CookieHTTPOnly:    true,
-				CookieDomain:      "pomerium.io",
-				CookieExpire:      10 * time.Second,
-				Encoder:           encoder,
-				BearerTokenHeader: "Authorization",
+				Name:           "_cookie",
+				CookieSecure:   true,
+				CookieHTTPOnly: true,
+				CookieDomain:   "pomerium.io",
+				CookieExpire:   10 * time.Second,
+				Encoder:        encoder,
 			},
 			false},
 		{"missing name",
 			&CookieStoreOptions{
-				Name:              "",
-				CookieSecure:      true,
-				CookieHTTPOnly:    true,
-				CookieDomain:      "pomerium.io",
-				CookieExpire:      10 * time.Second,
-				Encoder:           encoder,
-				BearerTokenHeader: "Authorization",
+				Name:           "",
+				CookieSecure:   true,
+				CookieHTTPOnly: true,
+				CookieDomain:   "pomerium.io",
+				CookieExpire:   10 * time.Second,
+				Encoder:        encoder,
 			},
 			nil,
 			true},
@@ -250,23 +247,3 @@ func TestMockSessionStore(t *testing.T) {
 		})
 	}
 }
-
-func Test_ParentSubdomain(t *testing.T) {
-	t.Parallel()
-	tests := []struct {
-		s    string
-		want string
-	}{
-		{"httpbin.corp.example.com", "corp.example.com"},
-		{"some.httpbin.corp.example.com", "httpbin.corp.example.com"},
-		{"example.com", ""},
-		{"", ""},
-	}
-	for _, tt := range tests {
-		t.Run(tt.s, func(t *testing.T) {
-			if got := ParentSubdomain(tt.s); got != tt.want {
-				t.Errorf("ParentSubdomain() = %v, want %v", got, tt.want)
-			}
-		})
-	}
-}

internal/sessions/header_store.go

@@ -0,0 +1,61 @@
+package sessions // import "github.com/pomerium/pomerium/internal/sessions"
+
+import (
+	"net/http"
+	"strings"
+
+	"github.com/pomerium/pomerium/internal/cryptutil"
+)
+
+const (
+	// defaultAuthHeader and defaultAuthType are default header name for the
+	// authorization bearer  token header as defined in rfc2617
+	// https://tools.ietf.org/html/rfc6750#section-2.1
+	defaultAuthHeader = "Authorization"
+	defaultAuthType   = "Bearer"
+)
+
+// HeaderStore implements the load session store interface using http
+// authorization headers.
+type HeaderStore struct {
+	authHeader string
+	authType   string
+	encoder    cryptutil.SecureEncoder
+}
+
+// NewHeaderStore returns a new header store for loading sessions from
+// authorization headers.
+func NewHeaderStore(enc cryptutil.SecureEncoder) *HeaderStore {
+	return &HeaderStore{
+		authHeader: defaultAuthHeader,
+		authType:   defaultAuthType,
+		encoder:    enc,
+	}
+}
+
+// LoadSession tries to retrieve the token string from the Authorization header.
+//
+// NOTA BENE: While most servers do not log Authorization headers by default,
+// you should ensure no other services are logging or leaking your auth headers.
+func (as *HeaderStore) LoadSession(r *http.Request) (*State, error) {
+	cipherText := as.tokenFromHeader(r)
+	if cipherText == "" {
+		return nil, ErrNoSessionFound
+	}
+	session, err := UnmarshalSession(cipherText, as.encoder)
+	if err != nil {
+		return nil, ErrMalformed
+	}
+	return session, nil
+
+}
+
+// retrieve the value of the authorization header
+func (as *HeaderStore) tokenFromHeader(r *http.Request) string {
+	bearer := r.Header.Get(as.authHeader)
+	atSize := len(as.authType)
+	if len(bearer) > atSize && strings.EqualFold(bearer[0:atSize], as.authType) {
+		return bearer[atSize+1:]
+	}
+	return ""
+}

internal/sessions/middleware.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"errors"
 	"net/http"
-	"strings"
 )
 
 // Context keys
@@ -13,65 +12,56 @@ var (
 	ErrorCtxKey   = &contextKey{"Error"}
 )
 
-// Library errors
-var (
-	ErrExpired        = errors.New("internal/sessions: session is expired")
-	ErrNoSessionFound = errors.New("internal/sessions: session is not found")
-	ErrMalformed      = errors.New("internal/sessions: session is malformed")
-)
-
-// RetrieveSession http middleware handler will verify a auth session from a http request.
-//
 // RetrieveSession will search for a auth session in a http request, in the order:
 //   1. `pomerium_session` URI query parameter
 //   2. `Authorization: BEARER` request header
 //   3. Cookie `_pomerium` value
-func RetrieveSession(s SessionStore) func(http.Handler) http.Handler {
+func RetrieveSession(s ...SessionLoader) func(http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
-		return retrieve(s, TokenFromQuery, TokenFromHeader, TokenFromCookie)(next)
+		return retrieve(s...)(next)
 	}
 }
 
-func retrieve(s SessionStore, findTokenFns ...func(r *http.Request) string) func(http.Handler) http.Handler {
+func retrieve(s ...SessionLoader) func(http.Handler) http.Handler {
 	return func(next http.Handler) http.Handler {
 		hfn := func(w http.ResponseWriter, r *http.Request) {
 			ctx := r.Context()
-			token, err := retrieveFromRequest(s, r, findTokenFns...)
-			ctx = NewContext(ctx, token, err)
+			state, err := retrieveFromRequest(r, s...)
+			ctx = NewContext(ctx, state, err)
 			next.ServeHTTP(w, r.WithContext(ctx))
 		}
 		return http.HandlerFunc(hfn)
 	}
 }
 
-func retrieveFromRequest(s SessionStore, r *http.Request, findTokenFns ...func(r *http.Request) string) (*State, error) {
-	var tokenStr string
+func retrieveFromRequest(r *http.Request, sessions ...SessionLoader) (*State, error) {
+	state := new(State)
 	var err error
 
-	// Extract token string from the request by calling token find functions in
+	// Extract sessions state from the request by calling token find functions in
 	// the order they where provided. Further extraction stops if a function
 	// returns a non-empty string.
-	for _, fn := range findTokenFns {
-		tokenStr = fn(r)
-		if tokenStr != "" {
+	for _, s := range sessions {
+		state, err = s.LoadSession(r)
+		if err != nil && !errors.Is(err, ErrNoSessionFound) {
+			//  unexpected error
+			return nil, err
+		}
+		// break, we found a session state
+		if state != nil {
 			break
 		}
 	}
-	if tokenStr == "" {
+	// no session found if state is still empty
+	if state == nil {
 		return nil, ErrNoSessionFound
 	}
 
-	state, err := s.LoadSession(r)
-	if err != nil {
-		return nil, ErrMalformed
-	}
-	err = state.Valid()
-	if err != nil {
+	if err = state.Valid(); err != nil {
 		// a little unusual but we want to return the expired state too
 		return state, err
 	}
 
-	// Valid!
 	return state, nil
 }
 
@@ -89,35 +79,6 @@ func FromContext(ctx context.Context) (*State, error) {
 	return state, err
 }
 
-// TokenFromCookie tries to retrieve the token string from a cookie named
-// "_pomerium".
-func TokenFromCookie(r *http.Request) string {
-	cookie, err := r.Cookie("_pomerium")
-	if err != nil {
-		return ""
-	}
-	return cookie.Value
-}
-
-// TokenFromHeader tries to retrieve the token string from the
-// "Authorization" request header: "Authorization: BEARER T".
-func TokenFromHeader(r *http.Request) string {
-	// Get token from authorization header.
-	bearer := r.Header.Get("Authorization")
-	if len(bearer) > 7 && strings.EqualFold(bearer[0:6], "BEARER") {
-		return bearer[7:]
-	}
-	return ""
-}
-
-// TokenFromQuery tries to retrieve the token string from the "pomerium_session" URI
-// query parameter.
-// todo(bdd) : document setting session code as queryparam
-func TokenFromQuery(r *http.Request) string {
-	// Get token from query param named "pomerium_session".
-	return r.URL.Query().Get("pomerium_session")
-}
-
 // contextKey is a value for use with context.WithValue. It's used as
 // a pointer so it fits in an interface{} without allocation. This technique
 // for defining context keys was copied from Go 1.7's new use of context in net/http.
@@ -126,5 +87,5 @@ type contextKey struct {
 }
 
 func (k *contextKey) String() string {
-	return "SessionStore context value " + k.name
+	return "context value " + k.name
 }

internal/sessions/middleware_test.go

@@ -9,9 +9,8 @@ import (
 	"testing"
 	"time"
 
-	"github.com/pomerium/pomerium/internal/cryptutil"
-
 	"github.com/google/go-cmp/cmp"
+	"github.com/pomerium/pomerium/internal/cryptutil"
 )
 
 func TestNewContext(t *testing.T) {
@@ -75,8 +74,8 @@ func TestVerifier(t *testing.T) {
 		{"expired auth header", State{Email: "user@pomerium.io", RefreshDeadline: time.Now().Add(-10 * time.Second)}, false, true, false, "internal/sessions: session is expired\n", http.StatusUnauthorized},
 		{"malformed auth header", State{Email: "user@pomerium.io", RefreshDeadline: time.Now().Add(-10 * time.Second)}, false, true, false, "internal/sessions: session is malformed\n", http.StatusUnauthorized},
 		{"good auth query param session", State{Email: "user@pomerium.io", RefreshDeadline: time.Now().Add(10 * time.Second)}, false, true, true, http.StatusText(http.StatusOK), http.StatusOK},
-		{"expired auth query param", State{Email: "user@pomerium.io", RefreshDeadline: time.Now().Add(-10 * time.Second)}, false, true, true, "internal/sessions: session is expired\n", http.StatusUnauthorized},
-		{"malformed auth query param", State{Email: "user@pomerium.io", RefreshDeadline: time.Now().Add(-10 * time.Second)}, false, true, true, "internal/sessions: session is malformed\n", http.StatusUnauthorized},
+		{"expired auth query param", State{Email: "user@pomerium.io", RefreshDeadline: time.Now().Add(-10 * time.Second)}, false, false, true, "internal/sessions: session is expired\n", http.StatusUnauthorized},
+		{"malformed auth query param", State{Email: "user@pomerium.io", RefreshDeadline: time.Now().Add(-10 * time.Second)}, false, false, true, "internal/sessions: session is malformed\n", http.StatusUnauthorized},
 		{"no session", State{Email: "user@pomerium.io", RefreshDeadline: time.Now().Add(-10 * time.Second)}, false, false, false, "internal/sessions: session is not found\n", http.StatusUnauthorized},
 	}
 	for _, tt := range tests {
@@ -94,7 +93,6 @@ func TestVerifier(t *testing.T) {
 			if strings.Contains(tt.name, "malformed") {
 				// add some garbage to the end of the string
 				encSession += cryptutil.NewBase64Key()
-				fmt.Println(encSession)
 			}
 
 			cs, err := NewCookieStore(&CookieStoreOptions{
@@ -104,6 +102,9 @@ func TestVerifier(t *testing.T) {
 			if err != nil {
 				t.Fatal(err)
 			}
+			as := NewHeaderStore(encoder)
+
+			qp := NewQueryParamStore(encoder)
 
 			r := httptest.NewRequest(http.MethodGet, "/", nil)
 			r.Header.Set("Accept", "application/json")
@@ -114,11 +115,12 @@ func TestVerifier(t *testing.T) {
 				r.Header.Set("Authorization", "Bearer "+encSession)
 			} else if tt.param {
 				q := r.URL.Query()
-				q.Add("pomerium_session", encSession)
+
+				q.Set("pomerium_session", encSession)
 				r.URL.RawQuery = q.Encode()
 			}
 
-			got := RetrieveSession(cs)(testAuthorizer((fnh)))
+			got := RetrieveSession(cs, as, qp)(testAuthorizer((fnh)))
 			got.ServeHTTP(w, r)
 
 			gotBody := w.Body.String()
@@ -133,3 +135,23 @@ func TestVerifier(t *testing.T) {
 		})
 	}
 }
+
+func Test_contextKey_String(t *testing.T) {
+	tests := []struct {
+		name    string
+		keyName string
+		want    string
+	}{
+		{"simple example", "test", "context value test"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			k := &contextKey{
+				name: tt.keyName,
+			}
+			if got := k.String(); got != tt.want {
+				t.Errorf("contextKey.String() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

internal/sessions/query_store.go

@@ -0,0 +1,44 @@
+package sessions // import "github.com/pomerium/pomerium/internal/sessions"
+
+import (
+	"net/http"
+
+	"github.com/pomerium/pomerium/internal/cryptutil"
+)
+
+const (
+	defaultQueryParamKey = "pomerium_session"
+)
+
+// QueryParamStore implements the load session store interface using http
+// query strings / query parameters.
+type QueryParamStore struct {
+	queryParamKey string
+	encoder       cryptutil.SecureEncoder
+}
+
+// NewQueryParamStore returns a new query param store for loading sessions from
+// query strings / query parameters.
+func NewQueryParamStore(enc cryptutil.SecureEncoder) *QueryParamStore {
+	return &QueryParamStore{
+		queryParamKey: defaultQueryParamKey,
+		encoder:       enc,
+	}
+}
+
+// LoadSession tries to retrieve the token string from URL query parameters.
+//
+// NOTA BENE: By default, most servers _DO_ log query params, the leaking or
+// accidental logging of which should be considered a security issue.
+func (qp *QueryParamStore) LoadSession(r *http.Request) (*State, error) {
+	cipherText := r.URL.Query().Get(qp.queryParamKey)
+	if cipherText == "" {
+		return nil, ErrNoSessionFound
+	}
+	session, err := UnmarshalSession(cipherText, qp.encoder)
+	if err != nil {
+		return nil, ErrMalformed
+	}
+	return session, nil
+
+}

internal/sessions/store.go

@@ -5,8 +5,14 @@ import (
 	"net/http"
 )
 
-// ErrEmptySession is an error for an empty sessions.
-var ErrEmptySession = errors.New("internal/sessions: empty session")
+var (
+	// ErrExpired is the error for an expired session.
+	ErrExpired = errors.New("internal/sessions: session is expired")
+	// ErrNoSessionFound is the error for when no session is found.
+	ErrNoSessionFound = errors.New("internal/sessions: session is not found")
+	// ErrMalformed is the error for when a session is found but is malformed.
+	ErrMalformed = errors.New("internal/sessions: session is malformed")
+)
 
 // SessionStore has the functions for setting, getting, and clearing the Session cookie
 type SessionStore interface {
@@ -14,3 +20,9 @@ type SessionStore interface {
 	LoadSession(*http.Request) (*State, error)
 	SaveSession(http.ResponseWriter, *http.Request, *State) error
 }
+
+// SessionLoader is implemented by any struct that loads a pomerium session
+// given a request, and returns a user state.
+type SessionLoader interface {
+	LoadSession(*http.Request) (*State, error)
+}

internal/sessions/util.go

@@ -0,0 +1,12 @@
+package sessions // import "github.com/pomerium/pomerium/internal/sessions"
+
+import "strings"
+
+// ParentSubdomain returns the parent subdomain.
+func ParentSubdomain(s string) string {
+	if strings.Count(s, ".") < 2 {
+		return ""
+	}
+	split := strings.SplitN(s, ".", 2)
+	return split[1]
+}

internal/sessions/util_test.go

@@ -0,0 +1,23 @@
+package sessions
+
+import "testing"
+
+func Test_ParentSubdomain(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		s    string
+		want string
+	}{
+		{"httpbin.corp.example.com", "corp.example.com"},
+		{"some.httpbin.corp.example.com", "httpbin.corp.example.com"},
+		{"example.com", ""},
+		{"", ""},
+	}
+	for _, tt := range tests {
+		t.Run(tt.s, func(t *testing.T) {
+			if got := ParentSubdomain(tt.s); got != tt.want {
+				t.Errorf("ParentSubdomain() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

proxy/handlers.go

@@ -184,8 +184,8 @@ func (p *Proxy) Verify(w http.ResponseWriter, r *http.Request) {
 	}
 	// check the queryparams to see if this check immediately followed
 	// authentication. If so, redirect back to the originally requested hostname.
-	if isCallback := r.URL.Query().Get(disableCallback); isCallback == "true" {
-		http.Redirect(w, r, "http://"+hostname, http.StatusFound)
+	if isCallback := r.URL.Query().Get("pomerium-auth-callback"); isCallback == "true" {
+		http.Redirect(w, r, hostname, http.StatusFound)
 		return
 	}
 

proxy/handlers_test.go

@@ -302,13 +302,13 @@ func TestProxy_VerifyWithMiddleware(t *testing.T) {
 		authorizer   clients.Authorizer
 		wantStatus   int
 	}{
-		{"good", opts, nil, http.MethodGet, "false", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: true}, http.StatusOK},
-		{"good post auth redirect", opts, nil, http.MethodGet, "true", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: true}, http.StatusFound},
-		{"not authorized", opts, nil, http.MethodGet, "false", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: false}, http.StatusForbidden},
-		{"not authorized expired, redirect to auth", opts, nil, http.MethodGet, "false", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(-10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: false}, http.StatusFound},
-		{"not authorized expired, don't redirect!", opts, nil, http.MethodGet, "true", "/.pomerium/verify/some.domain.name?no_redirect=true", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(-10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: false}, http.StatusUnauthorized},
-		{"not authorized because of error", opts, nil, http.MethodGet, "false", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeError: errors.New("authz error")}, http.StatusInternalServerError},
-		{"bad context retrieval error", opts, errors.New("oh no"), http.MethodGet, "false", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: true}, http.StatusOK},
+		{"good", opts, nil, http.MethodGet, "", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: true}, http.StatusOK},
+		{"good post auth redirect", opts, nil, http.MethodGet, "pomerium-auth-callback", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: true}, http.StatusFound},
+		{"not authorized", opts, nil, http.MethodGet, "", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: false}, http.StatusForbidden},
+		{"not authorized expired, redirect to auth", opts, nil, http.MethodGet, "", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(-10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: false}, http.StatusFound},
+		{"not authorized expired, don't redirect!", opts, nil, http.MethodGet, HeaderNoAuthRedirect, "/.pomerium/verify/some.domain.name?no_redirect=true", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(-10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: false}, http.StatusUnauthorized},
+		{"not authorized because of error", opts, nil, http.MethodGet, "", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeError: errors.New("authz error")}, http.StatusInternalServerError},
+		{"bad context retrieval error", opts, errors.New("oh no"), http.MethodGet, "", "/.pomerium/verify/some.domain.name", &cryptutil.MockEncoder{}, &sessions.MockSessionStore{Session: &sessions.State{Email: "user@test.example", RefreshDeadline: time.Now().Add(10 * time.Second)}}, clients.MockAuthorize{AuthorizeResponse: true}, http.StatusOK},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
@@ -322,8 +322,8 @@ func TestProxy_VerifyWithMiddleware(t *testing.T) {
 			p.UpdateOptions(tt.options)
 			uri := &url.URL{Path: tt.path}
 			queryString := uri.Query()
-			if tt.qp == "true" {
-				queryString.Set("pomerium-auth-callback", tt.qp)
+			if tt.qp != "" {
+				queryString.Set(tt.qp, "true")
 			}
 			uri.RawQuery = queryString.Encode()
 

proxy/middleware.go

@@ -23,7 +23,9 @@ const (
 	// HeaderGroups is the header key containing the user's groups.
 	HeaderGroups = "x-pomerium-authenticated-user-groups"
 
-	disableCallback = "pomerium-auth-callback"
+	// HeaderNoAuthRedirect is the header / query param key used to disable
+	// redirecting unauthenticated request by default but instead return a 401.
+	HeaderNoAuthRedirect = "x-pomerium-no-auth-redirect"
 )
 
 // AuthenticateSession is middleware to enforce a valid authentication
@@ -33,8 +35,8 @@ func (p *Proxy) AuthenticateSession(next http.Handler) http.Handler {
 		ctx, span := trace.StartSpan(r.Context(), "middleware.AuthenticateSession")
 		defer span.End()
 		s, err := sessions.FromContext(r.Context())
-		if err != nil {
-			log.Debug().Str("cause", err.Error()).Msg("proxy: re-authenticating due to session state error")
+		if err != nil || s == nil {
+			log.Debug().Msg("proxy: re-authenticating due to session state error")
 			p.reqNeedsAuthentication(w, r)
 			return
 		}
@@ -58,7 +60,7 @@ func (p *Proxy) AuthorizeSession(next http.Handler) http.Handler {
 		ctx, span := trace.StartSpan(r.Context(), "middleware.AuthorizeSession")
 		defer span.End()
 		s, err := sessions.FromContext(r.Context())
-		if err != nil {
+		if err != nil || s == nil {
 			httputil.ErrorResponse(w, r.WithContext(ctx), httputil.Error("", http.StatusForbidden, err))
 			return
 		}
@@ -105,9 +107,11 @@ func (p *Proxy) reqNeedsAuthentication(w http.ResponseWriter, r *http.Request) {
 	// some proxies like nginx won't follow redirects, and treat any
 	// non 2xx or 4xx status as an internal service error.
 	// https://nginx.org/en/docs/http/ngx_http_auth_request_module.html
-	if _, ok := r.URL.Query()[disableCallback]; ok {
+	redirectHeader := r.Header.Get(HeaderNoAuthRedirect)
+	if _, ok := r.URL.Query()[HeaderNoAuthRedirect]; ok || redirectHeader == "true" {
 		http.Error(w, http.StatusText(http.StatusUnauthorized), http.StatusUnauthorized)
 	}
+	r.Header.Get(HeaderNoAuthRedirect)
 	uri := urlutil.SignedRedirectURL(p.SharedKey, p.authenticateSigninURL, urlutil.GetAbsoluteURL(r))
 	http.Redirect(w, r, uri.String(), http.StatusFound)
 }

proxy/proxy.go

@@ -78,6 +78,7 @@ type Proxy struct {
 	refreshCooldown        time.Duration
 	Handler                http.Handler
 	sessionStore           sessions.SessionStore
+	sessionLoaders         []sessions.SessionLoader
 	signingKey             string
 	templates              *template.Template
 }
@@ -122,8 +123,12 @@ func New(opts config.Options) (*Proxy, error) {
 		defaultUpstreamTimeout: opts.DefaultUpstreamTimeout,
 		refreshCooldown:        opts.RefreshCooldown,
 		sessionStore:           cookieStore,
-		signingKey:             opts.SigningKey,
-		templates:              templates.New(),
+		sessionLoaders: []sessions.SessionLoader{
+			cookieStore,
+			sessions.NewHeaderStore(encoder),
+			sessions.NewQueryParamStore(encoder)},
+		signingKey: opts.SigningKey,
+		templates:  templates.New(),
 	}
 	// errors checked in ValidateOptions
 	p.authorizeURL, _ = urlutil.DeepCopy(opts.AuthorizeURL)
@@ -227,7 +232,7 @@ func (p *Proxy) reverseProxyHandler(r *mux.Router, policy *config.Policy) (*mux.
 	}
 
 	// 4. Retrieve the user session and add it to the request context
-	rp.Use(sessions.RetrieveSession(p.sessionStore))
+	rp.Use(sessions.RetrieveSession(p.sessionLoaders...))
 	// 5. Strip the user session cookie from the downstream request
 	rp.Use(middleware.StripCookie(p.cookieName))
 	// 6. AuthN - Verify the user is authenticated. Set email, group, & id headers