diff --git a/src/tls12.c b/src/tls12.c
index da43d99c..2a1756b0 100644
--- a/src/tls12.c
+++ b/src/tls12.c
@@ -503,6 +503,111 @@ int tls_record_set_handshake_server_key_exchange(uint8_t *record, size_t *record
 	return 1;
 }
 
+static int tls12_server_ecdh_params_from_bytes(uint8_t *curve_type, uint16_t *named_curve,
+	const uint8_t **point_octets, size_t *point_octets_len,
+	const uint8_t **in, size_t *inlen)
+{
+	if (!curve_type || !named_curve || !point_octets || !point_octets_len
+		|| !in || !(*in) || !inlen) {
+		error_print();
+		return -1;
+	}
+	if (tls_uint8_from_bytes(curve_type, in, inlen) != 1
+		|| tls_uint16_from_bytes(named_curve, in, inlen) != 1
+		|| tls_uint8array_from_bytes(point_octets, point_octets_len, in, inlen) != 1) {
+		error_print();
+		return -1;
+	}
+	if (*curve_type != TLS_curve_type_named_curve) {
+		error_print();
+		return -1;
+	}
+	if (!tls_named_curve_name(*named_curve)) {
+		error_print();
+		return -1;
+	}
+	if (!*point_octets || !*point_octets_len) {
+		error_print();
+		return -1;
+	}
+	return 1;
+}
+
+static int tls12_server_key_exchange_params_from_bytes(int cipher_suite,
+	const uint8_t **params, size_t *params_len, const uint8_t **in, size_t *inlen)
+{
+	const uint8_t *start;
+
+	if (!params || !params_len || !in || !(*in) || !inlen) {
+		error_print();
+		return -1;
+	}
+
+	start = *in;
+	switch (cipher_suite) {
+	case TLS_cipher_ecdhe_sm4_cbc_sm3:
+	case TLS_cipher_ecdhe_sm4_gcm_sm3:
+	case TLS_cipher_ecdhe_ecdsa_with_aes_128_cbc_sha256:
+		{
+			uint8_t curve_type;
+			uint16_t named_curve;
+			const uint8_t *point_octets;
+			size_t point_octets_len;
+
+			if (tls12_server_ecdh_params_from_bytes(&curve_type, &named_curve,
+				&point_octets, &point_octets_len, in, inlen) != 1) {
+				error_print();
+				return -1;
+			}
+		}
+		break;
+	default:
+		error_print();
+		return -1;
+	}
+
+	*params = start;
+	*params_len = *in - start;
+	return 1;
+}
+
+static int tls12_record_get_handshake_server_key_exchange(const uint8_t *record, int cipher_suite,
+	const uint8_t **params, size_t *params_len,
+	uint16_t *sig_alg, const uint8_t **sig, size_t *siglen)
+{
+	int type;
+	const uint8_t *p;
+	size_t len;
+
+	if (!record || !params || !params_len || !sig_alg || !sig || !siglen) {
+		error_print();
+		return -1;
+	}
+	if (tls_record_get_handshake(record, &type, &p, &len) != 1) {
+		error_print();
+		return -1;
+	}
+	if (type != TLS_handshake_server_key_exchange) {
+		error_print();
+		return 0;
+	}
+
+	if (tls12_server_key_exchange_params_from_bytes(cipher_suite,
+			params, params_len, &p, &len) != 1
+		|| tls_uint16_from_bytes(sig_alg, &p, &len) != 1
+		|| tls_uint16array_from_bytes(sig, siglen, &p, &len) != 1
+		|| tls_length_is_zero(len) != 1) {
+		error_print();
+		return -1;
+	}
+	if (!tls_signature_scheme_name(*sig_alg)) {
+		error_print();
+		return -1;
+	}
+
+	return 1;
+}
+
 // 这个函数是有问题的，因为tlcp的格式和TLS不一样
 int tls_record_get_handshake_server_key_exchange(const uint8_t *record,
 	uint8_t *curve_type, uint16_t *named_curve,
@@ -524,9 +629,8 @@ int tls_record_get_handshake_server_key_exchange(const uint8_t *record,
 	}
 
 	*server_ecdh_params = p;
-	if (tls_uint8_from_bytes(curve_type, &p, &len) != 1
-		|| tls_uint16_from_bytes(named_curve, &p, &len) != 1
-		|| tls_uint8array_from_bytes(point_octets, point_octets_len, &p, &len) != 1) {
+	if (tls12_server_ecdh_params_from_bytes(curve_type, named_curve,
+		point_octets, point_octets_len, &p, &len) != 1) {
 		error_print();
 		return -1;
 	}
@@ -541,14 +645,6 @@ int tls_record_get_handshake_server_key_exchange(const uint8_t *record,
 		error_print();
 		return -1;
 	}
-	if (*curve_type != TLS_curve_type_named_curve) {
-		error_print();
-		return -1;
-	}
-	if (!tls_named_curve_name(*named_curve)) {
-		error_print();
-		return -1;
-	}
 	if (!tls_signature_scheme_name(*sig_alg)) {
 		error_print();
 		return -1;
@@ -1975,12 +2071,12 @@ int tls_signature_scheme_match_cipher_suite(int sig_alg, int cipher_suite)
 int tls_recv_server_key_exchange(TLS_CONNECT *conn)
 {
 	int ret;
-	uint8_t curve_type;
-	uint16_t named_curve;
-	const uint8_t *point_octets;
-	size_t point_octets_len;
-	const uint8_t *server_ecdh_params;
-	size_t server_ecdh_params_len;
+	uint8_t curve_type = 0;
+	uint16_t named_curve = 0;
+	const uint8_t *point_octets = NULL;
+	size_t point_octets_len = 0;
+	const uint8_t *server_ecdh_params = NULL;
+	size_t server_ecdh_params_len = 0;
 	uint16_t sig_alg;
 	const uint8_t *sig;
 	size_t siglen;
@@ -2012,10 +2108,8 @@ int tls_recv_server_key_exchange(TLS_CONNECT *conn)
 	tls12_record_trace(stderr, conn->record, conn->recordlen, 0, 0);
 
 
-	// 这个函数可能是有问题的，如果cipher_suite不同，ServerKeyExchange可能也是不同的
-	if ((ret = tls_record_get_handshake_server_key_exchange(conn->record,
-		&curve_type, &named_curve, &point_octets, &point_octets_len,
-		&server_ecdh_params, &server_ecdh_params_len,
+	if ((ret = tls12_record_get_handshake_server_key_exchange(conn->record,
+		conn->cipher_suite, &server_ecdh_params, &server_ecdh_params_len,
 		&sig_alg, &sig, &siglen)) < 0) {
 		error_print();
 		tls_send_alert(conn, TLS_alert_decode_error);
@@ -2032,8 +2126,32 @@ int tls_recv_server_key_exchange(TLS_CONNECT *conn)
 	}
 	tls_handshake_digest_print(stderr, 0, 0, "ServerKeyExchange", &conn->dgst_ctx);
 
+	switch (conn->cipher_suite) {
+	case TLS_cipher_ecdhe_sm4_cbc_sm3:
+	case TLS_cipher_ecdhe_sm4_gcm_sm3:
+	case TLS_cipher_ecdhe_ecdsa_with_aes_128_cbc_sha256:
+		{
+			const uint8_t *p = server_ecdh_params;
+			size_t len = server_ecdh_params_len;
+
+			if (tls12_server_ecdh_params_from_bytes(&curve_type, &named_curve,
+				&point_octets, &point_octets_len, &p, &len) != 1
+				|| tls_length_is_zero(len) != 1) {
+				error_print();
+				tls_send_alert(conn, TLS_alert_decode_error);
+				return -1;
+			}
+		}
+		break;
+	default:
+		error_print();
+		tls_send_alert(conn, TLS_alert_unexpected_message);
+		return -1;
+	}
+
 	if (curve_type != TLS_curve_type_named_curve) {
 		error_print();
+		tls_send_alert(conn, TLS_alert_illegal_parameter);
 		return -1;
 	}
 	// named_curve应该在supported_groups里面
@@ -2049,20 +2167,19 @@ int tls_recv_server_key_exchange(TLS_CONNECT *conn)
 
 	if (point_octets_len != 65) {
 		error_print();
+		tls_send_alert(conn, TLS_alert_illegal_parameter);
 		return -1;
 	}
 
 
 	if (tls_curve_match_cipher_suite(named_curve, conn->cipher_suite) != 1) {
 		error_print();
-		return -1;
-	}
-	if (point_octets_len != 65) {
-		error_print();
+		tls_send_alert(conn, TLS_alert_illegal_parameter);
 		return -1;
 	}
 	if (tls_signature_scheme_match_cipher_suite(sig_alg, conn->cipher_suite) != 1) {
 		error_print();
+		tls_send_alert(conn, TLS_alert_illegal_parameter);
 		return -1;
 	}
 
@@ -2130,9 +2247,10 @@ int tls_recv_server_key_exchange(TLS_CONNECT *conn)
 	if (x509_verify_init(&sign_ctx, &server_sign_key, sign_args, sign_argslen, sig, siglen) != 1
 		|| x509_verify_update(&sign_ctx, conn->client_random, 32) != 1
 		|| x509_verify_update(&sign_ctx, conn->server_random, 32) != 1
-		|| x509_verify_update(&sign_ctx, server_ecdh_params, 69) != 1
+		|| x509_verify_update(&sign_ctx, server_ecdh_params, server_ecdh_params_len) != 1
 		|| x509_verify_finish(&sign_ctx) != 1) {
 		error_print();
+		tls_send_alert(conn, TLS_alert_decrypt_error);
 		return -1;
 	}