1 files changed, 98 insertions, 5 deletions

diff --git a/src/tls/tlsv1_client_read.c b/src/tls/tlsv1_client_read.c
index 3269ecf..f78921d 100644
--- a/src/tls/tlsv1_client_read.c
+++ b/src/tls/tlsv1_client_read.c
@@ -1,6 +1,6 @@
 /*
  * TLSv1 client - read handshake message
- * Copyright (c) 2006-2011, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2006-2014, Jouni Malinen <j@w1.fi>
  *
  * This software may be distributed under the terms of the BSD license.
  * See README for more details.
@@ -409,10 +409,37 @@ static int tls_process_certificate(struct tlsv1_client *conn, u8 ct,
 }
 
 
+static unsigned int count_bits(const u8 *val, size_t len)
+{
+	size_t i;
+	unsigned int bits;
+	u8 tmp;
+
+	for (i = 0; i < len; i++) {
+		if (val[i])
+			break;
+	}
+	if (i == len)
+		return 0;
+
+	bits = (len - i - 1) * 8;
+	tmp = val[i];
+	while (tmp) {
+		bits++;
+		tmp >>= 1;
+	}
+
+	return bits;
+}
+
+
 static int tlsv1_process_diffie_hellman(struct tlsv1_client *conn,
-					const u8 *buf, size_t len)
+					const u8 *buf, size_t len,
+					tls_key_exchange key_exchange)
 {
-	const u8 *pos, *end;
+	const u8 *pos, *end, *server_params, *server_params_end;
+	u8 alert;
+	unsigned int bits;
 
 	tlsv1_client_free_dh(conn);
 
@@ -421,6 +448,7 @@ static int tlsv1_process_diffie_hellman(struct tlsv1_client *conn,
 
 	if (end - pos < 3)
 		goto fail;
+	server_params = pos;
 	conn->dh_p_len = WPA_GET_BE16(pos);
 	pos += 2;
 	if (conn->dh_p_len == 0 || end - pos < (int) conn->dh_p_len) {
@@ -428,6 +456,14 @@ static int tlsv1_process_diffie_hellman(struct tlsv1_client *conn,
 			   (unsigned long) conn->dh_p_len);
 		goto fail;
 	}
+	bits = count_bits(pos, conn->dh_p_len);
+	if (bits < 768) {
+		wpa_printf(MSG_INFO, "TLSv1: Reject under 768-bit DH prime (insecure; only %u bits)",
+			   bits);
+		wpa_hexdump(MSG_DEBUG, "TLSv1: Rejected DH prime",
+			    pos, conn->dh_p_len);
+		goto fail;
+	}
 	conn->dh_p = os_malloc(conn->dh_p_len);
 	if (conn->dh_p == NULL)
 		goto fail;
@@ -465,6 +501,59 @@ static int tlsv1_process_diffie_hellman(struct tlsv1_client *conn,
 	pos += conn->dh_ys_len;
 	wpa_hexdump(MSG_DEBUG, "TLSv1: DH Ys (server's public value)",
 		    conn->dh_ys, conn->dh_ys_len);
+	server_params_end = pos;
+
+	if (key_exchange == TLS_KEY_X_DHE_RSA) {
+		u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN];
+		int hlen;
+
+		if (conn->rl.tls_version == TLS_VERSION_1_2) {
+#ifdef CONFIG_TLSV12
+			/*
+			 * RFC 5246, 4.7:
+			 * TLS v1.2 adds explicit indication of the used
+			 * signature and hash algorithms.
+			 *
+			 * struct {
+			 *   HashAlgorithm hash;
+			 *   SignatureAlgorithm signature;
+			 * } SignatureAndHashAlgorithm;
+			 */
+			if (end - pos < 2)
+				goto fail;
+			if (pos[0] != TLS_HASH_ALG_SHA256 ||
+			    pos[1] != TLS_SIGN_ALG_RSA) {
+				wpa_printf(MSG_DEBUG, "TLSv1.2: Unsupported hash(%u)/signature(%u) algorithm",
+					   pos[0], pos[1]);
+				goto fail;
+			}
+			pos += 2;
+
+			hlen = tlsv12_key_x_server_params_hash(
+				conn->rl.tls_version, conn->client_random,
+				conn->server_random, server_params,
+				server_params_end - server_params, hash);
+#else /* CONFIG_TLSV12 */
+			goto fail;
+#endif /* CONFIG_TLSV12 */
+		} else {
+			hlen = tls_key_x_server_params_hash(
+				conn->rl.tls_version, conn->client_random,
+				conn->server_random, server_params,
+				server_params_end - server_params, hash);
+		}
+
+		if (hlen < 0)
+			goto fail;
+		wpa_hexdump(MSG_MSGDUMP, "TLSv1: ServerKeyExchange hash",
+			    hash, hlen);
+
+		if (tls_verify_signature(conn->rl.tls_version,
+					 conn->server_rsa_key,
+					 hash, hlen, pos, end - pos,
+					 &alert) < 0)
+			goto fail;
+	}
 
 	return 0;
 
@@ -543,8 +632,10 @@ static int tls_process_server_key_exchange(struct tlsv1_client *conn, u8 ct,
 
 	wpa_hexdump(MSG_DEBUG, "TLSv1: ServerKeyExchange", pos, len);
 	suite = tls_get_cipher_suite(conn->rl.cipher_suite);
-	if (suite && suite->key_exchange == TLS_KEY_X_DH_anon) {
-		if (tlsv1_process_diffie_hellman(conn, pos, len) < 0) {
+	if (suite && (suite->key_exchange == TLS_KEY_X_DH_anon ||
+		      suite->key_exchange == TLS_KEY_X_DHE_RSA)) {
+		if (tlsv1_process_diffie_hellman(conn, pos, len,
+						 suite->key_exchange) < 0) {
 			tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
 				  TLS_ALERT_DECODE_ERROR);
 			return -1;
@@ -873,6 +964,8 @@ static int tls_process_server_finished(struct tlsv1_client *conn, u8 ct,
 
 	if (os_memcmp(pos, verify_data, TLS_VERIFY_DATA_LEN) != 0) {
 		wpa_printf(MSG_INFO, "TLSv1: Mismatch in verify_data");
+		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
+			  TLS_ALERT_DECRYPT_ERROR);
 		return -1;
 	}