Move validator's signature verification into ClientHelper

briar-api/src/org/briarproject/api/clients/ClientHelper.java

@@ -6,6 +6,7 @@ import org.briarproject.api.data.BdfList;
 import org.briarproject.api.db.DbException;
 import org.briarproject.api.db.Transaction;
 import org.briarproject.api.sync.GroupId;
+import org.briarproject.api.sync.InvalidMessageException;
 import org.briarproject.api.sync.Message;
 import org.briarproject.api.sync.MessageId;
 
@@ -81,4 +82,8 @@ public interface ClientHelper {
 
 	byte[] sign(BdfList toSign, byte[] privateKey)
 			throws FormatException, GeneralSecurityException;
+
+	void verifySignature(byte[] sig, byte[] publicKey, BdfList signed)
+			throws InvalidMessageException;
+
 }

briar-core/src/org/briarproject/blogs/BlogPostValidator.java

@@ -6,10 +6,6 @@ import org.briarproject.api.blogs.BlogFactory;
 import org.briarproject.api.blogs.MessageType;
 import org.briarproject.api.clients.BdfMessageContext;
 import org.briarproject.api.clients.ClientHelper;
-import org.briarproject.api.crypto.CryptoComponent;
-import org.briarproject.api.crypto.KeyParser;
-import org.briarproject.api.crypto.PublicKey;
-import org.briarproject.api.crypto.Signature;
 import org.briarproject.api.data.BdfDictionary;
 import org.briarproject.api.data.BdfEntry;
 import org.briarproject.api.data.BdfList;
@@ -24,7 +20,6 @@ import org.briarproject.api.sync.MessageId;
 import org.briarproject.api.system.Clock;
 import org.briarproject.clients.BdfMessageValidator;
 
-import java.security.GeneralSecurityException;
 import java.util.Collection;
 import java.util.Collections;
 
@@ -48,18 +43,15 @@ import static org.briarproject.api.identity.AuthorConstants.MAX_SIGNATURE_LENGTH
 
 class BlogPostValidator extends BdfMessageValidator {
 
-	private final CryptoComponent crypto;
 	private final GroupFactory groupFactory;
 	private final MessageFactory messageFactory;
 	private final BlogFactory blogFactory;
 
-	BlogPostValidator(CryptoComponent crypto, GroupFactory groupFactory,
-			MessageFactory messageFactory, BlogFactory blogFactory,
-			ClientHelper clientHelper, MetadataEncoder metadataEncoder,
-			Clock clock) {
+	BlogPostValidator(GroupFactory groupFactory, MessageFactory messageFactory,
+			BlogFactory blogFactory, ClientHelper clientHelper,
+			MetadataEncoder metadataEncoder, Clock clock) {
 		super(clientHelper, metadataEncoder, clock);
 
-		this.crypto = crypto;
 		this.groupFactory = groupFactory;
 		this.messageFactory = messageFactory;
 		this.blogFactory = blogFactory;
@@ -109,7 +101,7 @@ class BlogPostValidator extends BdfMessageValidator {
 		BdfList signed = BdfList.of(g.getId(), m.getTimestamp(), postBody);
 		Blog b = blogFactory.parseBlog(g, ""); // description doesn't matter
 		Author a = b.getAuthor();
-		verifySignature(sig, a.getPublicKey(), signed);
+		clientHelper.verifySignature(sig, a.getPublicKey(), signed);
 
 		// Return the metadata and dependencies
 		BdfDictionary meta = new BdfDictionary();
@@ -150,7 +142,7 @@ class BlogPostValidator extends BdfMessageValidator {
 						currentId);
 		Blog b = blogFactory.parseBlog(g, ""); // description doesn't matter
 		Author a = b.getAuthor();
-		verifySignature(sig, a.getPublicKey(), signed);
+		clientHelper.verifySignature(sig, a.getPublicKey(), signed);
 
 		// Return the metadata and dependencies
 		BdfDictionary meta = new BdfDictionary();
@@ -267,26 +259,6 @@ class BlogPostValidator extends BdfMessageValidator {
 		return new BdfMessageContext(meta, dependencies);
 	}
 
-	private void verifySignature(byte[] sig, byte[] publicKey, BdfList signed)
-			throws InvalidMessageException {
-		try {
-			// Parse the public key
-			KeyParser keyParser = crypto.getSignatureKeyParser();
-			PublicKey key = keyParser.parsePublicKey(publicKey);
-			// Verify the signature
-			Signature signature = crypto.getSignature();
-			signature.initVerify(key);
-			signature.update(clientHelper.toByteArray(signed));
-			if (!signature.verify(sig)) {
-				throw new InvalidMessageException("Invalid signature");
-			}
-		} catch (GeneralSecurityException e) {
-			throw new InvalidMessageException("Invalid public key");
-		} catch (FormatException e) {
-			throw new InvalidMessageException(e);
-		}
-	}
-
 	static BdfDictionary authorToBdfDictionary(Author a) {
 		return BdfDictionary.of(
 				new BdfEntry(KEY_AUTHOR_ID, a.getId()),

briar-core/src/org/briarproject/blogs/BlogsModule.java

@@ -5,7 +5,6 @@ import org.briarproject.api.blogs.BlogManager;
 import org.briarproject.api.blogs.BlogPostFactory;
 import org.briarproject.api.clients.ClientHelper;
 import org.briarproject.api.contact.ContactManager;
-import org.briarproject.api.crypto.CryptoComponent;
 import org.briarproject.api.data.MetadataEncoder;
 import org.briarproject.api.identity.AuthorFactory;
 import org.briarproject.api.identity.IdentityManager;
@@ -64,14 +63,14 @@ public class BlogsModule {
 	@Provides
 	@Singleton
 	BlogPostValidator provideBlogPostValidator(
-			ValidationManager validationManager, CryptoComponent crypto,
-			GroupFactory groupFactory, MessageFactory messageFactory,
-			BlogFactory blogFactory, ClientHelper clientHelper,
-			MetadataEncoder metadataEncoder, Clock clock) {
+			ValidationManager validationManager, GroupFactory groupFactory,
+			MessageFactory messageFactory, BlogFactory blogFactory,
+			ClientHelper clientHelper, MetadataEncoder metadataEncoder,
+			Clock clock) {
 
-		BlogPostValidator validator = new BlogPostValidator(crypto,
-				groupFactory, messageFactory, blogFactory, clientHelper,
-				metadataEncoder, clock);
+		BlogPostValidator validator = new BlogPostValidator(groupFactory,
+				messageFactory, blogFactory, clientHelper, metadataEncoder,
+				clock);
 		validationManager.registerMessageValidator(CLIENT_ID, validator);
 
 		return validator;

briar-core/src/org/briarproject/clients/ClientHelperImpl.java

@@ -5,6 +5,7 @@ import org.briarproject.api.clients.ClientHelper;
 import org.briarproject.api.crypto.CryptoComponent;
 import org.briarproject.api.crypto.KeyParser;
 import org.briarproject.api.crypto.PrivateKey;
+import org.briarproject.api.crypto.PublicKey;
 import org.briarproject.api.crypto.Signature;
 import org.briarproject.api.data.BdfDictionary;
 import org.briarproject.api.data.BdfList;
@@ -19,6 +20,7 @@ import org.briarproject.api.db.DbException;
 import org.briarproject.api.db.Metadata;
 import org.briarproject.api.db.Transaction;
 import org.briarproject.api.sync.GroupId;
+import org.briarproject.api.sync.InvalidMessageException;
 import org.briarproject.api.sync.Message;
 import org.briarproject.api.sync.MessageFactory;
 import org.briarproject.api.sync.MessageId;
@@ -320,4 +322,26 @@ class ClientHelperImpl implements ClientHelper {
 		signature.update(toByteArray(toSign));
 		return signature.sign();
 	}
+
+	@Override
+	public void verifySignature(byte[] sig, byte[] publicKey, BdfList signed)
+			throws InvalidMessageException {
+		try {
+			// Parse the public key
+			KeyParser keyParser = cryptoComponent.getSignatureKeyParser();
+			PublicKey key = keyParser.parsePublicKey(publicKey);
+			// Verify the signature
+			Signature signature = cryptoComponent.getSignature();
+			signature.initVerify(key);
+			signature.update(toByteArray(signed));
+			if (!signature.verify(sig)) {
+				throw new InvalidMessageException("Invalid signature");
+			}
+		} catch (GeneralSecurityException e) {
+			throw new InvalidMessageException("Invalid public key");
+		} catch (FormatException e) {
+			throw new InvalidMessageException(e);
+		}
+	}
+
 }

briar-core/src/org/briarproject/forum/ForumModule.java

@@ -54,11 +54,11 @@ public class ForumModule {
 	@Provides
 	@Singleton
 	ForumPostValidator provideForumPostValidator(
-			ValidationManager validationManager, CryptoComponent crypto,
-			AuthorFactory authorFactory, ClientHelper clientHelper,
-			MetadataEncoder metadataEncoder, Clock clock) {
-		ForumPostValidator validator = new ForumPostValidator(crypto,
-				authorFactory, clientHelper, metadataEncoder, clock);
+			ValidationManager validationManager, AuthorFactory authorFactory,
+			ClientHelper clientHelper, MetadataEncoder metadataEncoder,
+			Clock clock) {
+		ForumPostValidator validator = new ForumPostValidator(authorFactory,
+				clientHelper, metadataEncoder, clock);
 		validationManager.registerMessageValidator(
 				ForumManagerImpl.CLIENT_ID, validator);
 		return validator;

briar-core/src/org/briarproject/forum/ForumPostValidator.java

@@ -4,10 +4,6 @@ import org.briarproject.api.FormatException;
 import org.briarproject.api.UniqueId;
 import org.briarproject.api.clients.BdfMessageContext;
 import org.briarproject.api.clients.ClientHelper;
-import org.briarproject.api.crypto.CryptoComponent;
-import org.briarproject.api.crypto.KeyParser;
-import org.briarproject.api.crypto.PublicKey;
-import org.briarproject.api.crypto.Signature;
 import org.briarproject.api.data.BdfDictionary;
 import org.briarproject.api.data.BdfList;
 import org.briarproject.api.data.MetadataEncoder;
@@ -20,7 +16,6 @@ import org.briarproject.api.sync.MessageId;
 import org.briarproject.api.system.Clock;
 import org.briarproject.clients.BdfMessageValidator;
 
-import java.security.GeneralSecurityException;
 import java.util.Collection;
 import java.util.Collections;
 
@@ -32,14 +27,11 @@ import static org.briarproject.api.identity.AuthorConstants.MAX_SIGNATURE_LENGTH
 
 class ForumPostValidator extends BdfMessageValidator {
 
-	private final CryptoComponent crypto;
 	private final AuthorFactory authorFactory;
 
-	ForumPostValidator(CryptoComponent crypto, AuthorFactory authorFactory,
-			ClientHelper clientHelper, MetadataEncoder metadataEncoder,
-			Clock clock) {
+	ForumPostValidator(AuthorFactory authorFactory, ClientHelper clientHelper,
+			MetadataEncoder metadataEncoder, Clock clock) {
 		super(clientHelper, metadataEncoder, clock);
-		this.crypto = crypto;
 		this.authorFactory = authorFactory;
 	}
 
@@ -81,23 +73,10 @@ class ForumPostValidator extends BdfMessageValidator {
 		}
 		// Verify the signature, if any
 		if (author != null) {
-			try {
-				// Parse the public key
-				KeyParser keyParser = crypto.getSignatureKeyParser();
-				PublicKey key = keyParser.parsePublicKey(author.getPublicKey());
-				// Serialise the data to be signed
-				BdfList signed = BdfList.of(g.getId(), m.getTimestamp(), parent,
-						authorList, contentType, forumPostBody);
-				// Verify the signature
-				Signature signature = crypto.getSignature();
-				signature.initVerify(key);
-				signature.update(clientHelper.toByteArray(signed));
-				if (!signature.verify(sig)) {
-					throw new InvalidMessageException("Invalid signature");
-				}
-			} catch (GeneralSecurityException e) {
-				throw new InvalidMessageException("Invalid public key");
-			}
+			// Serialise the data to be signed
+			BdfList signed = BdfList.of(g.getId(), m.getTimestamp(), parent,
+					authorList, contentType, forumPostBody);
+			clientHelper.verifySignature(sig, author.getPublicKey(), signed);
 		}
 		// Return the metadata and dependencies
 		BdfDictionary meta = new BdfDictionary();

briar-tests/src/org/briarproject/blogs/BlogPostValidatorTest.java

@@ -7,9 +7,6 @@ import org.briarproject.api.blogs.Blog;
 import org.briarproject.api.blogs.BlogFactory;
 import org.briarproject.api.clients.ClientHelper;
 import org.briarproject.api.crypto.CryptoComponent;
-import org.briarproject.api.crypto.KeyParser;
-import org.briarproject.api.crypto.PublicKey;
-import org.briarproject.api.crypto.Signature;
 import org.briarproject.api.data.BdfDictionary;
 import org.briarproject.api.data.BdfEntry;
 import org.briarproject.api.data.BdfList;
@@ -20,7 +17,6 @@ import org.briarproject.api.sync.ClientId;
 import org.briarproject.api.sync.Group;
 import org.briarproject.api.sync.GroupFactory;
 import org.briarproject.api.sync.GroupId;
-import org.briarproject.api.sync.InvalidMessageException;
 import org.briarproject.api.sync.Message;
 import org.briarproject.api.sync.MessageFactory;
 import org.briarproject.api.sync.MessageId;
@@ -37,9 +33,9 @@ import static org.briarproject.api.blogs.BlogConstants.KEY_AUTHOR;
 import static org.briarproject.api.blogs.BlogConstants.KEY_AUTHOR_ID;
 import static org.briarproject.api.blogs.BlogConstants.KEY_AUTHOR_NAME;
 import static org.briarproject.api.blogs.BlogConstants.KEY_COMMENT;
+import static org.briarproject.api.blogs.BlogConstants.KEY_ORIGINAL_MSG_ID;
 import static org.briarproject.api.blogs.BlogConstants.KEY_ORIGINAL_PARENT_MSG_ID;
 import static org.briarproject.api.blogs.BlogConstants.KEY_PARENT_MSG_ID;
-import static org.briarproject.api.blogs.BlogConstants.KEY_ORIGINAL_MSG_ID;
 import static org.briarproject.api.blogs.BlogConstants.KEY_PUBLIC_KEY;
 import static org.briarproject.api.blogs.BlogConstants.KEY_READ;
 import static org.briarproject.api.blogs.MessageType.COMMENT;
@@ -94,9 +90,8 @@ public class BlogPostValidatorTest extends BriarTestCase {
 		message = new Message(messageId, group.getId(), timestamp, raw);
 
 		MetadataEncoder metadataEncoder = context.mock(MetadataEncoder.class);
-		validator = new BlogPostValidator(cryptoComponent, groupFactory,
-				messageFactory, blogFactory, clientHelper, metadataEncoder,
-				clock);
+		validator = new BlogPostValidator(groupFactory, messageFactory,
+				blogFactory, clientHelper, metadataEncoder, clock);
 		context.assertIsSatisfied();
 	}
 
@@ -108,7 +103,7 @@ public class BlogPostValidatorTest extends BriarTestCase {
 
 		BdfList signed =
 				BdfList.of(blog.getId(), message.getTimestamp(), body);
-		expectCrypto(signed, sigBytes, true);
+		expectCrypto(signed, sigBytes);
 		final BdfDictionary result =
 				validator.validateMessage(message, group, m).getDictionary();
 
@@ -135,18 +130,6 @@ public class BlogPostValidatorTest extends BriarTestCase {
 		validator.validateMessage(message, group, m).getDictionary();
 	}
 
-	@Test(expected = InvalidMessageException.class)
-	public void testValidateBlogPostWithBadSignature()
-			throws IOException, GeneralSecurityException {
-		final byte[] sigBytes = TestUtils.getRandomBytes(42);
-		BdfList m = BdfList.of(POST.getInt(), body, sigBytes);
-
-		BdfList signed =
-				BdfList.of(blog.getId(), message.getTimestamp(), body);
-		expectCrypto(signed, sigBytes, false);
-		validator.validateMessage(message, group, m).getDictionary();
-	}
-
 	@Test
 	public void testValidateProperBlogComment()
 			throws IOException, GeneralSecurityException {
@@ -162,7 +145,7 @@ public class BlogPostValidatorTest extends BriarTestCase {
 		BdfList signed =
 				BdfList.of(blog.getId(), message.getTimestamp(), comment,
 						pOriginalId, currentId);
-		expectCrypto(signed, sigBytes, true);
+		expectCrypto(signed, sigBytes);
 		final BdfDictionary result =
 				validator.validateMessage(message, group, m).getDictionary();
 
@@ -189,7 +172,7 @@ public class BlogPostValidatorTest extends BriarTestCase {
 		BdfList signed =
 				BdfList.of(blog.getId(), message.getTimestamp(), null,
 						originalId, currentId);
-		expectCrypto(signed, sigBytes, true);
+		expectCrypto(signed, sigBytes);
 		final BdfDictionary result =
 				validator.validateMessage(message, group, m).getDictionary();
 
@@ -208,7 +191,7 @@ public class BlogPostValidatorTest extends BriarTestCase {
 
 		BdfList signed =
 				BdfList.of(blog.getId(), message.getTimestamp(), body);
-		expectCrypto(signed, sigBytes, true);
+		expectCrypto(signed, sigBytes);
 
 		final BdfList originalList = BdfList.of(POST.getInt(), body, sigBytes);
 		final byte[] originalBody = TestUtils.getRandomBytes(42);
@@ -247,7 +230,7 @@ public class BlogPostValidatorTest extends BriarTestCase {
 
 		BdfList signed = BdfList.of(blog.getId(), message.getTimestamp(),
 				comment, originalId, oldId);
-		expectCrypto(signed, sigBytes, true);
+		expectCrypto(signed, sigBytes);
 
 		final BdfList originalList = BdfList.of(COMMENT.getInt(), comment,
 				originalId, oldId, sigBytes);
@@ -275,27 +258,13 @@ public class BlogPostValidatorTest extends BriarTestCase {
 		context.assertIsSatisfied();
 	}
 
-	private void expectCrypto(final BdfList signed, final byte[] sig,
-			final boolean pass) throws IOException, GeneralSecurityException {
-		final Signature signature = context.mock(Signature.class);
-		final KeyParser keyParser = context.mock(KeyParser.class);
-		final PublicKey publicKey = context.mock(PublicKey.class);
-
+	private void expectCrypto(final BdfList signed, final byte[] sig)
+			throws IOException, GeneralSecurityException {
 		context.checking(new Expectations() {{
 			oneOf(blogFactory).parseBlog(group, "");
 			will(returnValue(blog));
-			oneOf(cryptoComponent).getSignatureKeyParser();
-			will(returnValue(keyParser));
-			oneOf(keyParser).parsePublicKey(blog.getAuthor().getPublicKey());
-			will(returnValue(publicKey));
-			oneOf(cryptoComponent).getSignature();
-			will(returnValue(signature));
-			oneOf(signature).initVerify(publicKey);
-			oneOf(clientHelper).toByteArray(signed);
-			will(returnValue(sig));
-			oneOf(signature).update(sig);
-			oneOf(signature).verify(sig);
-			will(returnValue(pass));
+			oneOf(clientHelper)
+					.verifySignature(sig, author.getPublicKey(), signed);
 		}});
 	}