[SDK-4738] Add support for performing Pushed Authorization Requests (#…

…327)

Co-authored-by: Rita Zerrizuela <[email protected]>

authentication/oauth.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"net/url"
+	"strings"
 	"time"
 
 	"github.com/google/uuid"
@@ -207,6 +208,53 @@ func (o *OAuth) RevokeRefreshToken(ctx context.Context, body oauth.RevokeRefresh
 	return o.authentication.Request(ctx, "POST", o.authentication.URI("oauth", "revoke"), body, nil, opts...)
 }
 
+// PushedAuthorization performs a Pushed Authorization Request that can be used to initiate an OAuth flow from
+// the backchannel instead of building a URL.
+//
+// See: https://www.rfc-editor.org/rfc/rfc9126.html
+func (o *OAuth) PushedAuthorization(ctx context.Context, body oauth.PushedAuthorizationRequest, opts ...RequestOption) (p *oauth.PushedAuthorizationRequestResponse, err error) {
+	missing := []string{}
+	check(&missing, "ClientID", (body.ClientID != "" || o.authentication.clientID != ""))
+	check(&missing, "ResponseType", body.ResponseType != "")
+	check(&missing, "RedirectURI", body.RedirectURI != "")
+
+	if len(missing) > 0 {
+		return nil, fmt.Errorf("Missing required fields: %s", strings.Join(missing, ", "))
+	}
+
+	data := url.Values{
+		"response_type": []string{body.ResponseType},
+		"redirect_uri":  []string{body.RedirectURI},
+	}
+
+	addIfNotEmpty("scope", body.Scope, data)
+	addIfNotEmpty("audience", body.Audience, data)
+	addIfNotEmpty("nonce", body.Nonce, data)
+	addIfNotEmpty("response_mode", body.ResponseMode, data)
+	addIfNotEmpty("organization", body.Organization, data)
+	addIfNotEmpty("invitation", body.Invitation, data)
+	addIfNotEmpty("connection", body.Connection, data)
+	addIfNotEmpty("code_challenge", body.CodeChallenge, data)
+
+	for key, value := range body.ExtraParameters {
+		data.Set(key, value)
+	}
+
+	err = o.addClientAuthentication(body.ClientAuthentication, data, true)
+
+	if err != nil {
+		return nil, err
+	}
+
+	err = o.authentication.Request(ctx, "POST", o.authentication.URI("oauth", "par"), data, &p, opts...)
+
+	if err != nil {
+		return nil, err
+	}
+
+	return
+}
+
 func (o *OAuth) addClientAuthentication(params oauth.ClientAuthentication, body url.Values, required bool) error {
 	clientID := params.ClientID
 	if params.ClientID == "" {
@@ -289,3 +337,15 @@ func createClientAssertion(clientAssertionSigningAlg, clientAssertionSigningKey,
 
 	return string(b), nil
 }
+
+func addIfNotEmpty(key string, value string, qs url.Values) {
+	if value != "" {
+		qs.Set(key, value)
+	}
+}
+
+func check(errors *[]string, key string, c bool) {
+	if !c {
+		*errors = append(*errors, key)
+	}
+}

authentication/oauth/oauth.go

@@ -114,3 +114,36 @@ type IDTokenValidationOptions struct {
 	Nonce        string
 	Organization string
 }
+
+// PushedAuthorizationRequest defines the request body for performing a Pushed Authorization Request (PAR).
+type PushedAuthorizationRequest struct {
+	ClientAuthentication
+	// The URI to redirect to.
+	RedirectURI string
+	// Scopes to request.
+	Scope string
+	// The unique identifier of the target API you want to access.
+	Audience string
+	// The nonce.
+	Nonce string
+	// The response mode to use.
+	ResponseMode string
+	// The response type the client expects.
+	ResponseType string
+	// The organization to log the user in to.
+	Organization string
+	// The ID of an invitation to accept.
+	Invitation string
+	// Name of the connection.
+	Connection string
+	// A Base64-encoded SHA-256 hash of the code_verifier used for the Authorization Code Flow with PKCE.
+	CodeChallenge string
+	// Extra parameters to be added to the request. Values set here will override any existing values.
+	ExtraParameters map[string]string
+}
+
+// PushedAuthorizationRequestResponse defines the response from a Pushed Authorization Request.
+type PushedAuthorizationRequestResponse struct {
+	RequestURI string `json:"request_uri,omitempty"`
+	ExpiresIn  int    `json:"expires_in,omitempty"`
+}

authentication/oauth_test.go

@@ -408,6 +408,71 @@ func TestOAuthWithIDTokenVerification(t *testing.T) {
 	})
 }
 
+func TestPushedAuthorizationRequest(t *testing.T) {
+	t.Run("Should require a client secret", func(t *testing.T) {
+		_, err := authAPI.OAuth.PushedAuthorization(context.Background(), oauth.PushedAuthorizationRequest{
+			ResponseType: "code",
+			RedirectURI:  "http://localhost:3000/callback",
+		})
+		assert.ErrorContains(t, err, "client_secret or client_assertion is required but not provided")
+	})
+
+	t.Run("Should require a ClientID, ResponseType and RedirectURI", func(t *testing.T) {
+		auth, err := New(
+			context.Background(),
+			domain,
+		)
+		require.NoError(t, err)
+		_, err = auth.OAuth.PushedAuthorization(context.Background(), oauth.PushedAuthorizationRequest{})
+		assert.ErrorContains(t, err, "Missing required fields: ClientID, ResponseType, RedirectURI")
+	})
+
+	t.Run("Should make a PAR request", func(t *testing.T) {
+		skipE2E(t)
+		configureHTTPTestRecordings(t, authAPI)
+
+		res, err := authAPI.OAuth.PushedAuthorization(context.Background(), oauth.PushedAuthorizationRequest{
+			ClientAuthentication: oauth.ClientAuthentication{
+				ClientSecret: clientSecret,
+			},
+			ResponseType: "code",
+			RedirectURI:  "http://localhost:3000/callback",
+		})
+
+		require.NoError(t, err)
+		assert.NotEmpty(t, res.RequestURI)
+		assert.NotEmpty(t, res.ExpiresIn)
+	})
+
+	t.Run("Should support all arguments", func(t *testing.T) {
+		skipE2E(t)
+		configureHTTPTestRecordings(t, authAPI)
+
+		res, err := authAPI.OAuth.PushedAuthorization(context.Background(), oauth.PushedAuthorizationRequest{
+			ClientAuthentication: oauth.ClientAuthentication{
+				ClientSecret: clientSecret,
+			},
+			ResponseType:  "code",
+			RedirectURI:   "http://localhost:3000/callback",
+			Audience:      "test-audience",
+			Nonce:         "abc123",
+			ResponseMode:  "form_post",
+			Scope:         "openid profile email",
+			Organization:  "my-org",
+			Invitation:    "invite",
+			Connection:    "Username-Password",
+			CodeChallenge: "n4bQgYhMfWWaL-qgxVrQFaO_TxsrC4Is0V1sFbDwCgg",
+			ExtraParameters: map[string]string{
+				"test": "value",
+			},
+		})
+
+		require.NoError(t, err)
+		assert.NotEmpty(t, res.RequestURI)
+		assert.NotEmpty(t, res.ExpiresIn)
+	})
+}
+
 func withIDToken(t *testing.T, extras map[string]interface{}) (*Authentication, error) {
 	t.Helper()
 

test/data/recordings/authentication/TestPushedAuthorizationRequest/Should_make_a_PAR_request.yaml

@@ -0,0 +1,44 @@
+---
+version: 2
+interactions:
+    - id: 0
+      request:
+        proto: HTTP/1.1
+        proto_major: 1
+        proto_minor: 1
+        content_length: 194
+        transfer_encoding: []
+        trailer: {}
+        host: go-auth0-dev.eu.auth0.com
+        remote_addr: ""
+        request_uri: ""
+        body: client_id=test-client_id&client_secret=test-client_secret&redirect_uri=http%3A%2F%2Flocalhost%3A3000%2Fcallback&response_type=code
+        form:
+            client_id:
+                - test-client_id
+            client_secret:
+                - test-client_secret
+            redirect_uri:
+                - http://localhost:3000/callback
+            response_type:
+                - code
+        headers:
+            Content-Type:
+                - application/x-www-form-urlencoded
+        url: https://go-auth0-dev.eu.auth0.com/oauth/par
+        method: POST
+      response:
+        proto: HTTP/2.0
+        proto_major: 2
+        proto_minor: 0
+        transfer_encoding: []
+        trailer: {}
+        content_length: 132
+        uncompressed: false
+        body: '{"expires_in":30,"request_uri":"urn:ietf:params:oauth:request_uri:test-value"}'
+        headers:
+            Content-Type:
+                - application/json; charset=utf-8
+        status: 201 Created
+        code: 201
+        duration: 669.090416ms

test/data/recordings/authentication/TestPushedAuthorizationRequest/Should_support_all_arguments.yaml

@@ -0,0 +1,62 @@
+---
+version: 2
+interactions:
+    - id: 0
+      request:
+        proto: HTTP/1.1
+        proto_major: 1
+        proto_minor: 1
+        content_length: 395
+        transfer_encoding: []
+        trailer: {}
+        host: go-auth0-dev.eu.auth0.com
+        remote_addr: ""
+        request_uri: ""
+        body: audience=test-audience&client_id=test-client_id&client_secret=test-client_secret&code_challenge=n4bQgYhMfWWaL-qgxVrQFaO_TxsrC4Is0V1sFbDwCgg&connection=Username-Password&invitation=invite&nonce=abc123&organization=my-org&redirect_uri=http%3A%2F%2Flocalhost%3A3000%2Fcallback&response_mode=form_post&response_type=code&scope=openid+profile+email&test=value
+        form:
+            audience:
+                - test-audience
+            client_id:
+                - test-client_id
+            client_secret:
+                - test-client_secret
+            code_challenge:
+                - n4bQgYhMfWWaL-qgxVrQFaO_TxsrC4Is0V1sFbDwCgg
+            connection:
+                - Username-Password
+            invitation:
+                - invite
+            nonce:
+                - abc123
+            organization:
+                - my-org
+            redirect_uri:
+                - http://localhost:3000/callback
+            response_mode:
+                - form_post
+            response_type:
+                - code
+            scope:
+                - openid profile email
+            test:
+                - value
+        headers:
+            Content-Type:
+                - application/x-www-form-urlencoded
+        url: https://go-auth0-dev.eu.auth0.com/oauth/par
+        method: POST
+      response:
+        proto: HTTP/2.0
+        proto_major: 2
+        proto_minor: 0
+        transfer_encoding: []
+        trailer: {}
+        content_length: 132
+        uncompressed: false
+        body: '{"expires_in":30,"request_uri":"urn:ietf:params:oauth:request_uri:test-value"}'
+        headers:
+            Content-Type:
+                - application/json; charset=utf-8
+        status: 201 Created
+        code: 201
+        duration: 397.494667ms