- view = lttng_buffer_view_from_dynamic_buffer(&trigger_buffer, 0, -1);
- if (lttng_trigger_create_from_buffer(&view, &trigger) !=
- trigger_len) {
- ERR("Invalid trigger payload received in \"register trigger\" command");
- ret = LTTNG_ERR_INVALID_TRIGGER;
+ /* Receive fds, if any. */
+ if (cmd_ctx->lsm.fd_count > 0) {
+ ret = lttcomm_recv_payload_fds_unix_sock(
+ sock, cmd_ctx->lsm.fd_count, &trigger_payload);
+ if (ret > 0 && ret != cmd_ctx->lsm.fd_count * sizeof(int)) {
+ ret = LTTNG_ERR_INVALID_PROTOCOL;
+ goto end;
+ } else if (ret <= 0) {
+ ret = LTTNG_ERR_FATAL;
+ goto end;
+ }
+ }
+
+ /* Deserialize trigger. */
+ {
+ struct lttng_payload_view view =
+ lttng_payload_view_from_payload(
+ &trigger_payload, 0, -1);
+
+ if (lttng_trigger_create_from_payload(&view, &trigger) !=
+ trigger_len) {
+ ERR("Invalid trigger payload received in \"register trigger\" command");
+ ret = LTTNG_ERR_INVALID_TRIGGER;
+ goto end;
+ }
+ }
+
+ /*
+ * Validate the trigger credentials against the command credentials.
+ * Only the root user can register a trigger with non-matching
+ * credentials.
+ */
+ if (!lttng_credentials_is_equal_uid(
+ lttng_trigger_get_credentials(trigger),
+ &cmd_creds)) {
+ if (lttng_credentials_get_uid(&cmd_creds) != 0) {
+ ERR("Trigger credentials do not match the command credentials");
+ ret = LTTNG_ERR_INVALID_TRIGGER;
+ goto end;
+ }
+ }
+
+ /*
+ * The bytecode generation also serves as a validation step for the
+ * bytecode expressions.
+ */
+ ret = lttng_trigger_generate_bytecode(trigger, &cmd_creds);
+ if (ret != LTTNG_OK) {