Add a return value to tls_crypto_t.derive_secrets()

4 files changed, 44 insertions, 21 deletions

diff --git a/src/libtls/tls_crypto.c b/src/libtls/tls_crypto.c
index 4d84876d0..61632e78f 100644
--- a/src/libtls/tls_crypto.c
+++ b/src/libtls/tls_crypto.c
@@ -1495,7 +1495,7 @@ static void derive_master(private_tls_crypto_t *this, chunk_t premaster,
 /**
  * Expand key material from master secret
  */
-static void expand_keys(private_tls_crypto_t *this,
+static bool expand_keys(private_tls_crypto_t *this,
 						chunk_t client_random, chunk_t server_random)
 {
 	chunk_t seed, block, client_write, server_write;
@@ -1577,14 +1577,15 @@ static void expand_keys(private_tls_crypto_t *this,
 		this->prf->get_bytes(this->prf, this->msk_label, seed,
 							 this->msk.len, this->msk.ptr);
 	}
+	return TRUE;
 }
 
-METHOD(tls_crypto_t, derive_secrets, void,
+METHOD(tls_crypto_t, derive_secrets, bool,
 	private_tls_crypto_t *this, chunk_t premaster, chunk_t session,
 	identification_t *id, chunk_t client_random, chunk_t server_random)
 {
 	derive_master(this, premaster, session, id, client_random, server_random);
-	expand_keys(this, client_random, server_random);
+	return expand_keys(this, client_random, server_random);
 }
 
 METHOD(tls_crypto_t, resume_session, tls_cipher_suite_t,
@@ -1602,7 +1603,10 @@ METHOD(tls_crypto_t, resume_session, tls_cipher_suite_t,
 			if (this->suite)
 			{
 				this->prf->set_key(this->prf, master);
-				expand_keys(this, client_random, server_random);
+				if (!expand_keys(this, client_random, server_random))
+				{
+					this->suite = 0;
+				}
 			}
 			chunk_clear(&master);
 		}
diff --git a/src/libtls/tls_crypto.h b/src/libtls/tls_crypto.h
index 7430aea66..5512b1f48 100644
--- a/src/libtls/tls_crypto.h
+++ b/src/libtls/tls_crypto.h
@@ -515,8 +515,9 @@ struct tls_crypto_t {
 	 * @param id			identity the session is bound to
 	 * @param client_random	random data from client hello
 	 * @param server_random	random data from server hello
+	 * @return				TRUE if secrets derived successfully
 	 */
-	void (*derive_secrets)(tls_crypto_t *this, chunk_t premaster,
+	bool (*derive_secrets)(tls_crypto_t *this, chunk_t premaster,
 						   chunk_t session, identification_t *id,
 						   chunk_t client_random, chunk_t server_random);
 
diff --git a/src/libtls/tls_peer.c b/src/libtls/tls_peer.c
index 6091702cf..068dd3ae7 100644
--- a/src/libtls/tls_peer.c
+++ b/src/libtls/tls_peer.c
@@ -913,10 +913,14 @@ static status_t send_key_exchange_encrypt(private_tls_peer_t *this,
 	rng->destroy(rng);
 	htoun16(premaster, TLS_1_2);
 
-	this->crypto->derive_secrets(this->crypto, chunk_from_thing(premaster),
-								 this->session, this->server,
-								 chunk_from_thing(this->client_random),
-								 chunk_from_thing(this->server_random));
+	if (!this->crypto->derive_secrets(this->crypto, chunk_from_thing(premaster),
+									  this->session, this->server,
+									  chunk_from_thing(this->client_random),
+									  chunk_from_thing(this->server_random)))
+	{
+		this->alert->add(this->alert, TLS_FATAL, TLS_INTERNAL_ERROR);
+		return NEED_MORE;
+	}
 
 	public = find_public_key(this);
 	if (!public)
@@ -958,10 +962,15 @@ static status_t send_key_exchange_dhe(private_tls_peer_t *this,
 		this->alert->add(this->alert, TLS_FATAL, TLS_INTERNAL_ERROR);
 		return NEED_MORE;
 	}
-	this->crypto->derive_secrets(this->crypto, premaster,
-								 this->session, this->server,
-								 chunk_from_thing(this->client_random),
-								 chunk_from_thing(this->server_random));
+	if (!this->crypto->derive_secrets(this->crypto, premaster,
+									  this->session, this->server,
+									  chunk_from_thing(this->client_random),
+									  chunk_from_thing(this->server_random)))
+	{
+		this->alert->add(this->alert, TLS_FATAL, TLS_INTERNAL_ERROR);
+		chunk_clear(&premaster);
+		return NEED_MORE;
+	}
 	chunk_clear(&premaster);
 
 	this->dh->get_my_public_value(this->dh, &pub);
diff --git a/src/libtls/tls_server.c b/src/libtls/tls_server.c
index e3617dc9a..8d6a9336d 100644
--- a/src/libtls/tls_server.c
+++ b/src/libtls/tls_server.c
@@ -436,10 +436,14 @@ static status_t process_key_exchange_encrypted(private_tls_server_t *this,
 		DBG1(DBG_TLS, "decrypting Client Key Exchange failed");
 	}
 
-	this->crypto->derive_secrets(this->crypto, chunk_from_thing(premaster),
-								 this->session, this->peer,
-								 chunk_from_thing(this->client_random),
-								 chunk_from_thing(this->server_random));
+	if (!this->crypto->derive_secrets(this->crypto, chunk_from_thing(premaster),
+									  this->session, this->peer,
+									  chunk_from_thing(this->client_random),
+									  chunk_from_thing(this->server_random)))
+	{
+		this->alert->add(this->alert, TLS_FATAL, TLS_INTERNAL_ERROR);
+		return NEED_MORE;
+	}
 
 	this->state = STATE_KEY_EXCHANGE_RECEIVED;
 	return NEED_MORE;
@@ -485,10 +489,15 @@ static status_t process_key_exchange_dhe(private_tls_server_t *this,
 		return NEED_MORE;
 	}
 
-	this->crypto->derive_secrets(this->crypto, premaster,
-								 this->session, this->peer,
-								 chunk_from_thing(this->client_random),
-								 chunk_from_thing(this->server_random));
+	if (!this->crypto->derive_secrets(this->crypto, premaster,
+									  this->session, this->peer,
+									  chunk_from_thing(this->client_random),
+									  chunk_from_thing(this->server_random)))
+	{
+		this->alert->add(this->alert, TLS_FATAL, TLS_INTERNAL_ERROR);
+		chunk_clear(&premaster);
+		return NEED_MORE;
+	}
 	chunk_clear(&premaster);
 
 	this->state = STATE_KEY_EXCHANGE_RECEIVED;