tls: avoid some clang warnings

src/tls/openssl/tls.c

@@ -1953,6 +1953,9 @@ int bio_sni_from_client_hello(BIO *bio, struct pl *sni)
 
 		/* Server Name length */
 		err  = pl_bin_u16(&sniext, &sn_len);
+		if (err)
+			return err;
+
 		if (sn_len >= TLSEXT_MAXLEN_host_name)
 			return EINVAL;
 
@@ -2112,6 +2115,7 @@ struct tls_cert *tls_cert_for_sni(const struct tls *tls, const struct pl *sni)
 {
 	struct tls_cert *tls_cert = NULL;
 	struct le *le;
+	int sz;
 	char *cn;
 
 	if (!tls || !list_head(&tls->certs))
@@ -2120,7 +2124,11 @@ struct tls_cert *tls_cert_for_sni(const struct tls *tls, const struct pl *sni)
 	if (!pl_isset(sni))
 		return list_head(&tls->certs)->data;
 
-	cn = mem_zalloc(sni->l + 1, NULL);
+	if (sni->l >= TLSEXT_MAXLEN_host_name)
+		return NULL;
+
+	sz = (int) sni->l + 1;
+	cn = mem_zalloc(sz, NULL);
 	LIST_FOREACH(&tls->certs, le) {
 		X509 *x509;
 		X509_NAME *nm;
@@ -2135,7 +2143,7 @@ struct tls_cert *tls_cert_for_sni(const struct tls *tls, const struct pl *sni)
 		}
 
 		nm = X509_get_subject_name(x509);
-		X509_NAME_get_text_by_NID(nm, NID_commonName, cn, sni->l + 1);
+		X509_NAME_get_text_by_NID(nm, NID_commonName, cn, sz);
 		if (!pl_strcmp(sni, cn))
 			break;
 

src/tls/openssl/tls_tcp.c

@@ -216,7 +216,7 @@ static bool estab_handler(int *err, bool active, void *arg)
 static int tls_use_cert(struct tls_conn *tc, struct tls_cert *uc)
 {
 	int err;
-	int r;
+	long r;
 
 #if !defined(LIBRESSL_VERSION_NUMBER)
 	SSL_certs_clear(tc->ssl);