submission: Move relay part of QUIT command to submission-backend-rel…

…ay.c.
dovecot · Oct 9, 2018 · b7cceee · b7cceee
1 parent cdb809b
commit b7cceee
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Showing 5 changed files with 102 additions and 114 deletions.
diff --git a/src/submission/Makefile.am b/src/submission/Makefile.am
@@ -33,11 +33,7 @@ submission_DEPENDENCIES = \
 	$(LIBDOVECOT_STORAGE_DEPS) \
 	$(LIBDOVECOT_DEPS)
 
-cmds = \
-	cmd-quit.c
-
 submission_SOURCES = \
-	$(cmds) \
 	main.c \
 	submission-backend-relay.c \
 	submission-client.c \

diff --git a/src/submission/cmd-quit.c b/src/submission/cmd-quit.c
diff --git a/src/submission/submission-backend-relay.c b/src/submission/submission-backend-relay.c
@@ -576,3 +576,104 @@ int cmd_noop_relay(struct client *client, struct smtp_server_cmd_ctx *cmd)
 		(client->proxy_conn, 0, cmd_noop_proxy_cb, noop_cmd);
 	return 0;
 }
+
+/*
+ * QUIT command
+ */
+
+struct relay_cmd_quit_context {
+	struct client *client;
+	struct smtp_server_cmd_ctx *cmd;
+	struct smtp_client_command *cmd_proxied;
+};
+
+static void
+relay_cmd_quit_destroy(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
+		       struct relay_cmd_quit_context *quit_cmd)
+{
+	if (quit_cmd->cmd_proxied != NULL)
+		smtp_client_command_abort(&quit_cmd->cmd_proxied);
+}
+
+static void
+relay_cmd_quit_replied(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
+		       struct relay_cmd_quit_context *quit_cmd)
+{
+	if (quit_cmd->cmd_proxied != NULL)
+		smtp_client_command_abort(&quit_cmd->cmd_proxied);
+}
+
+static void relay_cmd_quit_finish(struct relay_cmd_quit_context *quit_cmd)
+{
+	struct smtp_server_cmd_ctx *cmd = quit_cmd->cmd;
+
+	if (quit_cmd->cmd_proxied != NULL)
+		smtp_client_command_abort(&quit_cmd->cmd_proxied);
+	smtp_server_reply_quit(cmd);
+}
+
+static void
+relay_cmd_quit_proxy_cb(const struct smtp_reply *proxy_reply ATTR_UNUSED,
+			struct relay_cmd_quit_context *quit_cmd)
+{
+	quit_cmd->cmd_proxied = NULL;
+	relay_cmd_quit_finish(quit_cmd);
+}
+
+static void relay_cmd_quit_proxy(struct relay_cmd_quit_context *quit_cmd)
+{
+	struct client *client = quit_cmd->client;
+	struct smtp_server_cmd_ctx *cmd = quit_cmd->cmd;
+
+	if (quit_cmd->cmd_proxied != NULL)
+		return;
+
+	if (smtp_client_connection_get_state(client->proxy_conn)
+		< SMTP_CLIENT_CONNECTION_STATE_READY) {
+		/* Don't bother proxying QUIT command when proxy is not
+		   fully initialized. */
+		smtp_server_reply_quit(cmd);
+		return;
+	}
+
+	/* RFC 5321, Section 4.1.1.10:
+
+	   The sender MUST NOT intentionally close the transmission channel
+	   until it sends a QUIT command, and it SHOULD wait until it receives
+	   the reply (even if there was an error response to a previous
+	   command). */
+	quit_cmd->cmd_proxied =
+		smtp_client_command_new(client->proxy_conn, 0,
+					relay_cmd_quit_proxy_cb, quit_cmd);
+	smtp_client_command_write(quit_cmd->cmd_proxied, "QUIT");
+	smtp_client_command_submit(quit_cmd->cmd_proxied);
+}
+
+static void
+relay_cmd_quit_next(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
+		    struct relay_cmd_quit_context *quit_cmd)
+{
+	/* QUIT command is next to reply */
+	relay_cmd_quit_proxy(quit_cmd);
+}
+
+int cmd_quit_relay(struct client *client, struct smtp_server_cmd_ctx *cmd)
+{
+	struct relay_cmd_quit_context *quit_cmd;
+
+	quit_cmd = p_new(cmd->pool, struct relay_cmd_quit_context, 1);
+	quit_cmd->client = client;
+	quit_cmd->cmd = cmd;
+
+	smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_NEXT,
+				     relay_cmd_quit_next, quit_cmd);
+	smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_REPLIED,
+				     relay_cmd_quit_replied, quit_cmd);
+	smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_DESTROY,
+				     relay_cmd_quit_destroy, quit_cmd);
+
+	if (smtp_client_connection_get_state(client->proxy_conn)
+		>= SMTP_CLIENT_CONNECTION_STATE_READY)
+		relay_cmd_quit_proxy(quit_cmd);
+	return 0;
+}
diff --git a/src/submission/submission-backend-relay.h b/src/submission/submission-backend-relay.h
@@ -14,5 +14,6 @@ int cmd_data_relay(struct client *client, struct smtp_server_cmd_ctx *cmd,
 int cmd_vrfy_relay(struct client *client, struct smtp_server_cmd_ctx *cmd,
 		   const char *param);
 int cmd_noop_relay(struct client *client, struct smtp_server_cmd_ctx *cmd);
+int cmd_quit_relay(struct client *client, struct smtp_server_cmd_ctx *cmd);
 
 #endif
diff --git a/src/submission/submission-commands.h b/src/submission/submission-commands.h
@@ -4,8 +4,6 @@
 bool client_command_handle_proxy_reply(struct client *client,
 	const struct smtp_reply *reply, struct smtp_reply *reply_r);
 
-int cmd_quit_relay(struct client *client, struct smtp_server_cmd_ctx *cmd);
-
 void submission_helo_reply_submit(struct smtp_server_cmd_ctx *cmd,
 				  struct smtp_server_cmd_helo *data);
 int cmd_helo(void *conn_ctx, struct smtp_server_cmd_ctx *cmd,