URL encode client credentials

Closes gh-9610

oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/AbstractWebClientReactiveOAuth2AccessTokenResponseClient.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,9 @@
 
 package org.springframework.security.oauth2.client.endpoint;
 
+import java.io.UnsupportedEncodingException;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
 import java.util.Collections;
 import java.util.Set;
 
@@ -97,7 +100,19 @@ public abstract class AbstractWebClientReactiveOAuth2AccessTokenResponseClient<T
 		headers.setAccept(Collections.singletonList(MediaType.APPLICATION_JSON));
 		if (ClientAuthenticationMethod.CLIENT_SECRET_BASIC.equals(clientRegistration.getClientAuthenticationMethod())
 				|| ClientAuthenticationMethod.BASIC.equals(clientRegistration.getClientAuthenticationMethod())) {
-			headers.setBasicAuth(clientRegistration.getClientId(), clientRegistration.getClientSecret());
+			String clientId = encodeClientCredential(clientRegistration.getClientId());
+			String clientSecret = encodeClientCredential(clientRegistration.getClientSecret());
+			headers.setBasicAuth(clientId, clientSecret);
+		}
+	}
+
+	private static String encodeClientCredential(String clientCredential) {
+		try {
+			return URLEncoder.encode(clientCredential, StandardCharsets.UTF_8.toString());
+		}
+		catch (UnsupportedEncodingException ex) {
+			// Will not happen since UTF-8 is a standard charset
+			throw new IllegalArgumentException(ex);
 		}
 	}
 

oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationGrantRequestEntityUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,9 @@
 
 package org.springframework.security.oauth2.client.endpoint;
 
+import java.io.UnsupportedEncodingException;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
 import java.util.Collections;
 
 import org.springframework.core.convert.converter.Converter;
@@ -48,11 +51,23 @@ final class OAuth2AuthorizationGrantRequestEntityUtils {
 		headers.addAll(DEFAULT_TOKEN_REQUEST_HEADERS);
 		if (ClientAuthenticationMethod.CLIENT_SECRET_BASIC.equals(clientRegistration.getClientAuthenticationMethod())
 				|| ClientAuthenticationMethod.BASIC.equals(clientRegistration.getClientAuthenticationMethod())) {
-			headers.setBasicAuth(clientRegistration.getClientId(), clientRegistration.getClientSecret());
+			String clientId = encodeClientCredential(clientRegistration.getClientId());
+			String clientSecret = encodeClientCredential(clientRegistration.getClientSecret());
+			headers.setBasicAuth(clientId, clientSecret);
 		}
 		return headers;
 	}
 
+	private static String encodeClientCredential(String clientCredential) {
+		try {
+			return URLEncoder.encode(clientCredential, StandardCharsets.UTF_8.toString());
+		}
+		catch (UnsupportedEncodingException ex) {
+			// Will not happen since UTF-8 is a standard charset
+			throw new IllegalArgumentException(ex);
+		}
+	}
+
 	private static HttpHeaders getDefaultTokenRequestHeaders() {
 		HttpHeaders headers = new HttpHeaders();
 		headers.setAccept(Collections.singletonList(MediaType.APPLICATION_JSON_UTF8));

oauth2/oauth2-client/src/test/java/org/springframework/security/oauth2/client/endpoint/OAuth2ClientCredentialsGrantRequestEntityConverterTests.java

@@ -16,6 +16,11 @@
 
 package org.springframework.security.oauth2.client.endpoint;
 
+import java.io.UnsupportedEncodingException;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
+import java.util.Base64;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.mockito.InOrder;
@@ -128,4 +133,37 @@ public class OAuth2ClientCredentialsGrantRequestEntityConverterTests {
 		assertThat(formParameters.getFirst(OAuth2ParameterNames.SCOPE)).contains(clientRegistration.getScopes());
 	}
 
+	// gh-9610
+	@SuppressWarnings("unchecked")
+	@Test
+	public void convertWhenSpecialCharactersThenConvertsWithEncodedClientCredentials()
+			throws UnsupportedEncodingException {
+		String clientCredentialWithAnsiKeyboardSpecialCharacters = "~!@#$%^&*()_+{}|:\"<>?`-=[]\\;',./ ";
+		// @formatter:off
+		ClientRegistration clientRegistration = TestClientRegistrations.clientCredentials()
+				.clientId(clientCredentialWithAnsiKeyboardSpecialCharacters)
+				.clientSecret(clientCredentialWithAnsiKeyboardSpecialCharacters)
+				.build();
+		// @formatter:on
+		OAuth2ClientCredentialsGrantRequest clientCredentialsGrantRequest = new OAuth2ClientCredentialsGrantRequest(
+				clientRegistration);
+		RequestEntity<?> requestEntity = this.converter.convert(clientCredentialsGrantRequest);
+		assertThat(requestEntity.getMethod()).isEqualTo(HttpMethod.POST);
+		assertThat(requestEntity.getUrl().toASCIIString())
+				.isEqualTo(clientRegistration.getProviderDetails().getTokenUri());
+		HttpHeaders headers = requestEntity.getHeaders();
+		assertThat(headers.getAccept()).contains(MediaType.APPLICATION_JSON_UTF8);
+		assertThat(headers.getContentType())
+				.isEqualTo(MediaType.valueOf(MediaType.APPLICATION_FORM_URLENCODED_VALUE + ";charset=UTF-8"));
+		String urlEncodedClientCredential = URLEncoder.encode(clientCredentialWithAnsiKeyboardSpecialCharacters,
+				StandardCharsets.UTF_8.toString());
+		String clientCredentials = Base64.getEncoder().encodeToString(
+				(urlEncodedClientCredential + ":" + urlEncodedClientCredential).getBytes(StandardCharsets.UTF_8));
+		assertThat(headers.getFirst(HttpHeaders.AUTHORIZATION)).isEqualTo("Basic " + clientCredentials);
+		MultiValueMap<String, String> formParameters = (MultiValueMap<String, String>) requestEntity.getBody();
+		assertThat(formParameters.getFirst(OAuth2ParameterNames.GRANT_TYPE))
+				.isEqualTo(AuthorizationGrantType.CLIENT_CREDENTIALS.getValue());
+		assertThat(formParameters.getFirst(OAuth2ParameterNames.SCOPE)).contains(clientRegistration.getScopes());
+	}
+
 }

oauth2/oauth2-client/src/test/java/org/springframework/security/oauth2/client/endpoint/WebClientReactiveClientCredentialsTokenResponseClientTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,10 @@
 
 package org.springframework.security.oauth2.client.endpoint;
 
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
+import java.util.Base64;
+
 import okhttp3.mockwebserver.MockResponse;
 import okhttp3.mockwebserver.MockWebServer;
 import okhttp3.mockwebserver.RecordedRequest;
@@ -89,6 +93,35 @@ public class WebClientReactiveClientCredentialsTokenResponseClientTests {
 		assertThat(body).isEqualTo("grant_type=client_credentials&scope=read%3Auser");
 	}
 
+	// gh-9610
+	@Test
+	public void getTokenResponseWhenSpecialCharactersThenSuccessWithEncodedClientCredentials() throws Exception {
+		// @formatter:off
+		enqueueJson("{\n"
+			+ "  \"access_token\":\"MTQ0NjJkZmQ5OTM2NDE1ZTZjNGZmZjI3\",\n"
+			+ "  \"token_type\":\"bearer\",\n"
+			+ "  \"expires_in\":3600,\n"
+			+ "  \"refresh_token\":\"IwOGYzYTlmM2YxOTQ5MGE3YmNmMDFkNTVk\",\n"
+			+ "  \"scope\":\"create\"\n"
+			+ "}");
+		// @formatter:on
+		String clientCredentialWithAnsiKeyboardSpecialCharacters = "~!@#$%^&*()_+{}|:\"<>?`-=[]\\;',./ ";
+		OAuth2ClientCredentialsGrantRequest request = new OAuth2ClientCredentialsGrantRequest(
+				this.clientRegistration.clientId(clientCredentialWithAnsiKeyboardSpecialCharacters)
+						.clientSecret(clientCredentialWithAnsiKeyboardSpecialCharacters).build());
+		OAuth2AccessTokenResponse response = this.client.getTokenResponse(request).block();
+		RecordedRequest actualRequest = this.server.takeRequest();
+		String body = actualRequest.getBody().readUtf8();
+		assertThat(response.getAccessToken()).isNotNull();
+		String urlEncodedClientCredentialecret = URLEncoder.encode(clientCredentialWithAnsiKeyboardSpecialCharacters,
+				StandardCharsets.UTF_8.toString());
+		String clientCredentials = Base64.getEncoder()
+				.encodeToString((urlEncodedClientCredentialecret + ":" + urlEncodedClientCredentialecret)
+						.getBytes(StandardCharsets.UTF_8));
+		assertThat(actualRequest.getHeader(HttpHeaders.AUTHORIZATION)).isEqualTo("Basic " + clientCredentials);
+		assertThat(body).isEqualTo("grant_type=client_credentials&scope=read%3Auser");
+	}
+
 	@Test
 	public void getTokenResponseWhenPostThenSuccess() throws Exception {
 		ClientRegistration registration = this.clientRegistration