OpenSSL: Provide access to peer subject and own certificate use

These are needed for EAP-TEAP server and client side implementation to
allow Phase 2 to be skipped based on client certificate use during Phase
1.

Signed-off-by: Jouni Malinen <j@w1.fi>

src/crypto/tls.h

@@ -670,4 +670,18 @@ int tls_get_tls_unique(struct tls_connection *conn, u8 *buf, size_t max_len);
  */
 u16 tls_connection_get_cipher_suite(struct tls_connection *conn);
 
+/**
+ * tls_connection_get_peer_subject - Get peer subject
+ * @conn: Connection context data from tls_connection_init()
+ * Returns: Peer subject or %NULL if not authenticated or not available
+ */
+const char * tls_connection_get_peer_subject(struct tls_connection *conn);
+
+/**
+ * tls_connection_get_own_cert_used - Was own certificate used
+ * @conn: Connection context data from tls_connection_init()
+ * Returns: true if own certificate was used during authentication
+ */
+bool tls_connection_get_own_cert_used(struct tls_connection *conn);
+
 #endif /* TLS_H */

src/crypto/tls_openssl.c

@@ -265,6 +265,7 @@ struct tls_connection {
 	X509 *peer_cert;
 	X509 *peer_issuer;
 	X509 *peer_issuer_issuer;
+	char *peer_subject; /* peer subject info for authenticated peer */
 
 	unsigned char client_random[SSL3_RANDOM_SIZE];
 	unsigned char server_random[SSL3_RANDOM_SIZE];
@@ -1629,6 +1630,7 @@ void tls_connection_deinit(void *ssl_ctx, struct tls_connection *conn)
 	os_free(conn->domain_match);
 	os_free(conn->check_cert_subject);
 	os_free(conn->session_ticket);
+	os_free(conn->peer_subject);
 	os_free(conn);
 }
 
@@ -2579,6 +2581,11 @@ static int tls_verify_cb(int preverify_ok, X509_STORE_CTX *x509_ctx)
 		context->event_cb(context->cb_ctx,
 				  TLS_CERT_CHAIN_SUCCESS, NULL);
 
+	if (depth == 0 && preverify_ok) {
+		os_free(conn->peer_subject);
+		conn->peer_subject = os_strdup(buf);
+	}
+
 	return preverify_ok;
 }
 
@@ -3180,7 +3187,11 @@ int tls_connection_set_verify(void *ssl_ctx, struct tls_connection *conn,
 	if (conn == NULL)
 		return -1;
 
-	if (verify_peer) {
+	if (verify_peer == 2) {
+		conn->ca_cert_verify = 1;
+		SSL_set_verify(conn->ssl, SSL_VERIFY_PEER |
+			       SSL_VERIFY_CLIENT_ONCE, tls_verify_cb);
+	} else if (verify_peer) {
 		conn->ca_cert_verify = 1;
 		SSL_set_verify(conn->ssl, SSL_VERIFY_PEER |
 			       SSL_VERIFY_FAIL_IF_NO_PEER_CERT |
@@ -5683,3 +5694,19 @@ u16 tls_connection_get_cipher_suite(struct tls_connection *conn)
 	return SSL_CIPHER_get_id(cipher) & 0xFFFF;
 #endif
 }
+
+
+const char * tls_connection_get_peer_subject(struct tls_connection *conn)
+{
+	if (conn)
+		return conn->peer_subject;
+	return NULL;
+}
+
+
+bool tls_connection_get_own_cert_used(struct tls_connection *conn)
+{
+	if (conn)
+		return SSL_get_certificate(conn->ssl) != NULL;
+	return false;
+}