Allow AWS-EC2 nonce configuration.

We now allow nonce configuration via Nonce.generated()/Nonce.provided() and use with AwsEc2AuthenticationOptions.

Closes gh-89.

spring-vault-core/pom.xml

@@ -100,6 +100,13 @@
 			<version>1.16.10</version>
 			<optional>true</optional>
 		</dependency>
+
+		<dependency>
+			<groupId>org.slf4j</groupId>
+			<artifactId>slf4j-jcl</artifactId>
+			<version>1.7.16</version>
+			<scope>test</scope>
+		</dependency>
 	</dependencies>
 
 </project>

spring-vault-core/src/main/java/org/springframework/vault/authentication/AwsEc2Authentication.java

@@ -17,7 +17,6 @@ package org.springframework.vault.authentication;
 
 import java.util.HashMap;
 import java.util.Map;
-import java.util.UUID;
 import java.util.concurrent.atomic.AtomicReference;
 
 import org.apache.commons.logging.Log;
@@ -159,6 +158,6 @@ public class AwsEc2Authentication implements ClientAuthentication {
 	}
 
 	protected char[] createNonce() {
-		return UUID.randomUUID().toString().toCharArray();
+		return options.getNonce().getValue();
 	}
 }

spring-vault-core/src/main/java/org/springframework/vault/authentication/AwsEc2AuthenticationOptions.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 the original author or authors.
+ * Copyright 2016-2017 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 +16,8 @@
 package org.springframework.vault.authentication;
 
 import java.net.URI;
+import java.util.Arrays;
+import java.util.UUID;
 
 import org.springframework.util.Assert;
 
@@ -59,15 +61,23 @@ public class AwsEc2AuthenticationOptions {
 	 */
 	private final String role;
 
+	/**
+	 * Authentication nonce.
+	 */
+	private final Nonce nonce;
+
 	private AwsEc2AuthenticationOptions() {
-		this(DEFAULT_AWS_AUTHENTICATION_PATH, DEFAULT_PKCS7_IDENTITY_DOCUMENT_URI, "");
+		this(DEFAULT_AWS_AUTHENTICATION_PATH, DEFAULT_PKCS7_IDENTITY_DOCUMENT_URI, "",
+				Nonce.generated());
 	}
 
-	private AwsEc2AuthenticationOptions(String path, URI identityDocumentUri, String role) {
+	private AwsEc2AuthenticationOptions(String path, URI identityDocumentUri,
+			String role, Nonce nonce) {
 
 		this.path = path;
 		this.identityDocumentUri = identityDocumentUri;
 		this.role = role;
+		this.nonce = nonce;
 	}
 
 	/**
@@ -98,6 +108,13 @@ public class AwsEc2AuthenticationOptions {
 		return role;
 	}
 
+	/**
+	 * @return the configured {@link Nonce}.
+	 */
+	public Nonce getNonce() {
+		return nonce;
+	}
+
 	/**
 	 * Builder for {@link AwsEc2AuthenticationOptionsBuilder}.
 	 */
@@ -106,6 +123,7 @@ public class AwsEc2AuthenticationOptions {
 		private String path = DEFAULT_AWS_AUTHENTICATION_PATH;
 		private URI identityDocumentUri = DEFAULT_PKCS7_IDENTITY_DOCUMENT_URI;
 		private String role;
+		private Nonce nonce = Nonce.generated();
 
 		AwsEc2AuthenticationOptionsBuilder() {
 		}
@@ -152,6 +170,22 @@ public class AwsEc2AuthenticationOptions {
 			return this;
 		}
 
+		/**
+		 * Configure a {@link Nonce} for login requests. Defaults to
+		 * {@link Nonce#generated()}.
+		 *
+		 * @param nonce must not be {@literal null}.
+		 * @return {@code this} {@link AwsEc2AuthenticationOptionsBuilder}.
+		 * @since 1.1
+		 */
+		public AwsEc2AuthenticationOptionsBuilder nonce(Nonce nonce) {
+
+			Assert.notNull(nonce, "Nonce must not be null");
+
+			this.nonce = nonce;
+			return this;
+		}
+
 		/**
 		 * Build a new {@link AwsEc2AuthenticationOptions} instance.
 		 *
@@ -161,7 +195,63 @@ public class AwsEc2AuthenticationOptions {
 
 			Assert.notNull(identityDocumentUri, "IdentityDocumentUri must not be null");
 
-			return new AwsEc2AuthenticationOptions(path, identityDocumentUri, role);
+			return new AwsEc2AuthenticationOptions(path, identityDocumentUri, role, nonce);
+		}
+	}
+
+	/**
+	 * Value object for an authentication nonce.
+	 *
+	 * @since 1.1
+	 */
+	public static class Nonce {
+
+		private final char[] value;
+
+		protected Nonce(char[] value) {
+			this.value = value;
+		}
+
+		/**
+		 * Create a new generated {@link Nonce} using {@link UUID}.
+		 *
+		 * @return a new generated {@link Nonce} using {@link UUID}.
+		 */
+		public static Nonce generated() {
+			return new Generated();
+		}
+
+		/**
+		 * Create a wrapped {@link Nonce} given a {@code nonce} value.
+		 *
+		 * @return a wrapped {@link Nonce} given for the {@code nonce} value.
+		 */
+		public static Nonce provided(char[] nonce) {
+
+			Assert.notNull(nonce, "Nonce must not be null");
+
+			return new Provided(Arrays.copyOf(nonce, nonce.length));
+		}
+
+		/**
+		 * @return the nonce value.
+		 */
+		public char[] getValue() {
+			return value;
+		}
+
+		static class Generated extends Nonce {
+
+			Generated() {
+				super(UUID.randomUUID().toString().toCharArray());
+			}
+		}
+
+		static class Provided extends Nonce {
+
+			Provided(char[] nonce) {
+				super(nonce);
+			}
 		}
 	}
 }

spring-vault-core/src/test/java/org/springframework/vault/authentication/AwsEc2AuthenticationUnitTests.java

@@ -25,6 +25,7 @@ import org.springframework.http.HttpMethod;
 import org.springframework.http.MediaType;
 import org.springframework.test.web.client.MockRestServiceServer;
 import org.springframework.vault.VaultException;
+import org.springframework.vault.authentication.AwsEc2AuthenticationOptions.Nonce;
 import org.springframework.vault.client.VaultClients;
 import org.springframework.vault.client.VaultClients.PrefixAwareUriTemplateHandler;
 import org.springframework.vault.support.VaultToken;
@@ -94,9 +95,20 @@ public class AwsEc2AuthenticationUnitTests {
 	@Test
 	public void shouldLogin() throws Exception {
 
+		Nonce nonce = Nonce.provided("foo".toCharArray());
+
+		AwsEc2AuthenticationOptions authenticationOptions = AwsEc2AuthenticationOptions
+				.builder().nonce(nonce).build();
+
+		mockRest.expect(
+				requestTo("http://169.254.169.254/latest/dynamic/instance-identity/pkcs7")) //
+				.andExpect(method(HttpMethod.GET)) //
+				.andRespond(withSuccess().body("value"));
+
 		mockRest.expect(requestTo("/auth/aws-ec2/login"))
 				.andExpect(method(HttpMethod.POST))
 				.andExpect(jsonPath("$.pkcs7").value("value"))
+				.andExpect(jsonPath("$.nonce").value("foo"))
 				.andRespond(
 						withSuccess()
 								.contentType(MediaType.APPLICATION_JSON)
@@ -104,12 +116,8 @@ public class AwsEc2AuthenticationUnitTests {
 										+ "\"auth\":{\"client_token\":\"my-token\", \"lease_duration\":20}"
 										+ "}"));
 
-		AwsEc2Authentication authentication = new AwsEc2Authentication(restTemplate) {
-			@Override
-			protected Map<String, String> getEc2Login() {
-				return Collections.singletonMap("pkcs7", "value");
-			}
-		};
+		AwsEc2Authentication authentication = new AwsEc2Authentication(
+				authenticationOptions, restTemplate, restTemplate);
 
 		VaultToken login = authentication.login();