Enable server name verification on mbedTLS

PUBLISHED_FROM=54774944d5402a5d6a351b4609428940c0ad20ea

mongoose.c

@@ -4370,10 +4370,6 @@ enum mg_ssl_if_result mg_ssl_if_conn_init(
     return MG_SSL_ERROR;
   }
 
-  if (params->server_name != NULL) {
-    /* TODO(rojer): Implement server name verification on mbedTLS. */
-  }
-
   mg_set_cipher_list(ctx, NULL);
 
   if (!(nc->flags & MG_F_LISTENING)) {
@@ -4383,6 +4379,10 @@ enum mg_ssl_if_result mg_ssl_if_conn_init(
       MG_SET_PTRPTR(err_msg, "Failed to create SSL session");
       return MG_SSL_ERROR;
     }
+    if (params->server_name != NULL &&
+        mbedtls_ssl_set_hostname(ctx->ssl, params->server_name) != 0) {
+      return MG_SSL_ERROR;
+    }
   }
 
   nc->flags |= MG_F_SSL;