[Project] Lua_udp: Add initial prototype

src/lua/CMakeLists.txt

@@ -27,6 +27,7 @@ SET(LUASRC			  ${CMAKE_CURRENT_SOURCE_DIR}/lua_common.c
 					  ${CMAKE_CURRENT_SOURCE_DIR}/lua_cryptobox.c
 					  ${CMAKE_CURRENT_SOURCE_DIR}/lua_map.c
 					  ${CMAKE_CURRENT_SOURCE_DIR}/lua_thread_pool.c
-					  ${CMAKE_CURRENT_SOURCE_DIR}/lua_dns.c)
+					  ${CMAKE_CURRENT_SOURCE_DIR}/lua_dns.c
+					  ${CMAKE_CURRENT_SOURCE_DIR}/lua_udp.c)
 
 SET(RSPAMD_LUA ${LUASRC} PARENT_SCOPE)

src/lua/lua_common.c

@@ -784,6 +784,7 @@ rspamd_lua_init ()
 	luaopen_sqlite3 (L);
 	luaopen_cryptobox (L);
 	luaopen_dns (L);
+	luaopen_udp (L);
 
 	luaL_newmetatable (L, "rspamd{ev_base}");
 	lua_pushstring (L, "class");

src/lua/lua_common.h

@@ -282,6 +282,7 @@ void luaopen_fann (lua_State *L);
 void luaopen_sqlite3 (lua_State *L);
 void luaopen_cryptobox (lua_State *L);
 void luaopen_dns (lua_State *L);
+void luaopen_udp (lua_State * L);
 
 void rspamd_lua_dostring (const gchar *line);
 

src/lua/lua_dns_resolver.c

@@ -44,7 +44,6 @@ end
 static const gchar *M = "rspamd lua dns resolver";
 
 struct rspamd_dns_resolver * lua_check_dns_resolver (lua_State * L);
-void luaopen_dns_resolver (lua_State * L);
 
 /* Lua bindings */
 LUA_FUNCTION_DEF (dns_resolver, init);

src/lua/lua_udp.c

@@ -0,0 +1,363 @@
+/*-
+ * Copyright 2019 Vsevolod Stakhov
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include "lua_common.h"
+#include "lua_thread_pool.h"
+#include "utlist.h"
+#include "unix-std.h"
+#include <math.h>
+
+static const gchar *M = "rspamd lua udp";
+
+/***
+ * @module rspamd_udp
+ * Rspamd UDP module represents generic UDP asynchronous client available from LUA code.
+ * This module is quite simple: it can either send requests to some address or
+ * it can send requests and wait for replies, potentially handling retransmits.
+ * @example
+local logger = require "rspamd_logger"
+local udp = require "rspamd_udp"
+
+rspamd_config.SYM = function(task)
+  udp.sento({
+    host = addr, -- must be ip address object (e.g. received by upstream module)
+    port = 500,
+    data = data, -- can be table, string or rspamd_text
+    timeout = 0.5, -- default = 1s
+    task = task, -- if has task
+    session = session, -- optional
+    ev_base = ev_base, -- if no task available
+  }
+end
+ */
+
+static const double default_udp_timeout = 1.0;
+
+LUA_FUNCTION_DEF (udp, sendto);
+
+static const struct luaL_reg udp_libf[] = {
+	LUA_INTERFACE_DEF (udp, sendto),
+	{NULL, NULL}
+};
+
+struct lua_udp_cbdata {
+	struct event io;
+	struct event_base *ev_base;
+	rspamd_mempool_t *pool;
+	rspamd_inet_addr_t *addr;
+	struct rspamd_symcache_item *item;
+	struct rspamd_async_session *s;
+	struct iovec *iov;
+	lua_State *L;
+	guint iovlen;
+	gint sock;
+	gint cbref;
+};
+
+#define msg_debug_udp(...)  rspamd_conditional_debug_fast (NULL, cbd->addr, \
+        rspamd_lua_udp_log_id, "lua_udp", cbd->pool->tag.uid, \
+        G_STRFUNC, \
+        __VA_ARGS__)
+
+INIT_LOG_MODULE(lua_udp)
+
+static inline void
+lua_fill_iov (lua_State *L, rspamd_mempool_t *pool,
+		struct iovec *iov, gint pos)
+{
+	if (lua_type (L, pos) == LUA_TUSERDATA) {
+		struct rspamd_lua_text *t = lua_check_text (L, pos);
+
+		if (t) {
+			iov->iov_base = rspamd_mempool_alloc (pool, t->len);
+			iov->iov_len = t->len;
+			memcpy (iov->iov_base, t->start, t->len);
+		}
+	}
+	else {
+		const gchar *s;
+		gsize len;
+
+		s = lua_tolstring (L, pos, &len);
+
+		iov->iov_base = rspamd_mempool_alloc (pool, len);
+		iov->iov_len = len;
+		memcpy (iov->iov_base, s, len);
+	}
+}
+
+static void
+lua_udp_cbd_fin (gpointer p)
+{
+	struct lua_udp_cbdata *cbd = (struct lua_udp_cbdata *)p;
+
+	if (cbd->sock != -1) {
+		close (cbd->sock);
+	}
+
+	if (cbd->addr) {
+		rspamd_inet_address_free (cbd->addr);
+	}
+}
+
+
+enum rspamd_udp_send_result {
+	RSPAMD_SENT_OK,
+	RSPAMD_SENT_RETRY,
+	RSPAMD_SENT_FAILURE
+};
+
+static enum rspamd_udp_send_result
+lua_try_send_request (struct lua_udp_cbdata *cbd)
+{
+	struct msghdr msg;
+	gint r;
+
+	memset (&msg, 0, sizeof (msg));
+	msg.msg_iov = cbd->iov;
+	msg.msg_iovlen = cbd->iovlen;
+	msg.msg_name = rspamd_inet_address_get_sa (cbd->addr, &msg.msg_namelen);
+
+	r = sendmsg (cbd->sock, &msg, 0);
+
+	if (r != -1) {
+		return RSPAMD_SENT_OK;
+	}
+
+	if (errno == EAGAIN || errno == EINTR) {
+		return RSPAMD_SENT_RETRY;
+	}
+
+	return RSPAMD_SENT_FAILURE;
+}
+
+
+/***
+ * @function rspamd_tcp.request({params})
+ * This function creates and sends TCP request to the specified host and port,
+ * resolves hostname (if needed) and invokes continuation callback upon data received
+ * from the remote peer. This function accepts table of arguments with the following
+ * attributes
+ *
+ * - `task`: rspamd task objects (implies `pool`, `session`, `ev_base` and `resolver` arguments)
+ * - `ev_base`: event base (if no task specified)
+ * - `session`: events session (no task)
+ * - `host`: IP or name of the peer (required)
+ * - `port`: remote port to use
+ * - `data`: a table of strings or `rspamd_text` objects that contains data pieces
+ * - `callback`: continuation function (required)
+ * - `on_connect`: callback called on connection success
+ * - `timeout`: floating point value that specifies timeout for IO operations in **seconds**
+ * - `partial`: boolean flag that specifies that callback should be called on any data portion received
+ * - `stop_pattern`: stop reading on finding a certain pattern (e.g. \r\n.\r\n for smtp)
+ * - `shutdown`: half-close socket after writing (boolean: default false)
+ * - `read`: read response after sending request (boolean: default true)
+ * @return {boolean} true if request has been sent
+ */
+static gint
+lua_udp_sendto (lua_State *L) {
+	LUA_TRACE_POINT;
+	const gchar *host;
+	guint port;
+	gint cbref, tp, conn_cbref = -1;
+	struct event_base *ev_base = NULL;
+	struct lua_udp_cbdata *cbd;
+	struct rspamd_async_session *session = NULL;
+	struct rspamd_task *task = NULL;
+	rspamd_inet_addr_t *addr;
+	rspamd_mempool_t *pool = NULL;
+	struct iovec *iov = NULL;
+	guint niov = 0, total_out;
+	guint64 h;
+	gdouble timeout = default_udp_timeout;
+
+	if (lua_type (L, 1) == LUA_TTABLE) {
+		lua_pushstring (L, "port");
+		lua_gettable (L, -2);
+
+		if (lua_type (L, -1) == LUA_TNUMBER) {
+			port = luaL_checknumber (L, -1);
+		}
+		else {
+			/* We assume that it is a unix socket */
+			port = 0;
+		}
+
+		lua_pop (L, 1);
+
+		lua_pushstring (L, "host");
+		lua_gettable (L, -2);
+
+		if (lua_type (L, -1) == LUA_TSTRING) {
+			host = luaL_checkstring (L, -1);
+
+			if (rspamd_parse_inet_address (&addr, host, 0)) {
+				rspamd_inet_address_set_port (addr, port);
+			}
+			else {
+				lua_pop (L, 1);
+				return luaL_error (L, "invalid host: %s", host);
+			}
+		}
+		else if (lua_type (L, -1) == LUA_TUSERDATA) {
+			struct rspamd_lua_ip *lip;
+
+			lip = lua_check_ip (L, -1);
+
+			if (lip == NULL || lip->addr == NULL) {
+				lua_pop (L, 1);
+				return luaL_error (L, "invalid host class");
+			}
+
+			addr = rspamd_inet_address_copy (lip->addr);
+		}
+		else {
+			lua_pop (L, 1);
+			return luaL_error (L, "invalid host");
+		}
+
+		lua_pop (L, 1);
+
+		lua_pushstring (L, "task");
+		lua_gettable (L, -2);
+		if (lua_type (L, -1) == LUA_TUSERDATA) {
+			task = lua_check_task (L, -1);
+			ev_base = task->ev_base;
+			session = task->s;
+			pool = task->task_pool;
+		}
+		lua_pop (L, 1);
+
+		if (task == NULL) {
+			lua_pushstring (L, "ev_base");
+			lua_gettable (L, -2);
+			if (rspamd_lua_check_udata_maybe (L, -1, "rspamd{ev_base}")) {
+				ev_base = *(struct event_base **) lua_touserdata (L, -1);
+			} else {
+				ev_base = NULL;
+			}
+			lua_pop (L, 1);
+
+			lua_pushstring (L, "session");
+			lua_gettable (L, -2);
+			if (rspamd_lua_check_udata_maybe (L, -1, "rspamd{session}")) {
+				session = *(struct rspamd_async_session **) lua_touserdata (L, -1);
+			} else {
+				session = NULL;
+			}
+			lua_pop (L, 1);
+
+			lua_pushstring (L, "session");
+			lua_gettable (L, -2);
+			if (rspamd_lua_check_udata_maybe (L, -1, "rspamd{mempool}")) {
+				pool = *(rspamd_mempool_t **) lua_touserdata (L, -1);
+			} else {
+				pool = NULL;
+			}
+			lua_pop (L, 1);
+		}
+
+		lua_pushstring (L, "timeout");
+		lua_gettable (L, -2);
+		if (lua_type (L, -1) == LUA_TNUMBER) {
+			timeout = lua_tonumber (L, -1) * 1000.;
+		}
+		lua_pop (L, 1);
+
+		if (!ev_base || !pool) {
+			rspamd_inet_address_free (addr);
+
+			return luaL_error (L, "invalid arguments");
+		}
+
+		cbd = rspamd_mempool_alloc0 (pool, sizeof (*cbd));
+		cbd->ev_base = ev_base;
+		cbd->pool = pool;
+		cbd->s = session;
+		cbd->addr = addr;
+		cbd->sock = rspamd_socket_create (rspamd_inet_address_get_af (addr),
+				SOCK_DGRAM, 0, TRUE);
+
+		if (cbd->sock == -1) {
+			rspamd_inet_address_free (addr);
+
+			return luaL_error (L, "cannot open socket: %s", strerror (errno));
+		}
+
+		cbd->L = L;
+
+		gsize data_len;
+
+		lua_pushstring (L, "data");
+		if (lua_type (L, -1) == LUA_TTABLE) {
+			data_len = rspamd_lua_table_size (L, -1);
+			cbd->iov = rspamd_mempool_alloc (pool,
+					sizeof (*cbd->iov) * data_len);
+
+			for (int i = 0; i < data_len; i ++) {
+				lua_rawgeti (L, -1, i + 1);
+				lua_fill_iov (L, pool, &cbd->iov[i], -1);
+				lua_pop (L, 1);
+			}
+
+			cbd->iovlen = data_len;
+		}
+		else {
+			cbd->iov = rspamd_mempool_alloc (pool, sizeof (*cbd->iov));
+			cbd->iovlen = 1;
+			lua_fill_iov (L, pool, cbd->iov, -1);
+		}
+
+		lua_pop (L, 1);
+
+		enum rspamd_udp_send_result r;
+
+		r = lua_try_send_request (cbd);
+		if (r == RSPAMD_SENT_OK) {
+			lua_pushboolean (L, true);
+			lua_udp_cbd_fin (cbd);
+		}
+		else if (r == RSPAMD_SENT_FAILURE) {
+			lua_pushboolean (L, false);
+			lua_pushstring (L, strerror (errno));
+			lua_udp_cbd_fin (cbd);
+
+			return 2;
+		}
+		else {
+			/* TODO: add waiting */
+		}
+	}
+	else {
+		return luaL_error (L, "invalid arguments");
+	}
+
+	return 1;
+}
+
+static gint
+lua_load_udp (lua_State * L)
+{
+	lua_newtable (L);
+	luaL_register (L, NULL, udp_libf);
+
+	return 1;
+}
+
+void
+luaopen_udp (lua_State * L)
+{
+	rspamd_lua_add_preload (L, "rspamd_tcp", lua_load_udp);
+}