fix: fix compile warning of telnetd

Signed-off-by: staylightblow8 <liudf0716@gmail.com>

.gitignore

@@ -44,3 +44,4 @@ xfrpc
 xfrp_test_server
 bin
 .vscode
+build

CMakeLists.txt

@@ -75,18 +75,25 @@ set(src_xfrpc
 	common.c
 	login.c
 	proxy_tcp.c
+	proxy_udp.c
 	proxy_ftp.c
 	proxy.c
 	tcpmux.c
+	tcp_redir.c
 	)
-	
+
+set(src_xfrpc_plugins
+	plugins/telnetd.c)
+
 set(libs
 	ssl
 	crypto
 	event
 	z
 	m
-	json-c)
+	json-c
+	crypt
+	pthread)
 	
 set(test_libs
 	event
@@ -98,7 +105,7 @@ if (STATIC_BUILD STREQUAL "ON")
   add_link_options(-static)
 endif (STATIC_BUILD)
 
-add_executable(xfrpc ${src_xfrpc})
+add_executable(xfrpc ${src_xfrpc} ${src_xfrpc_plugins})
 target_link_libraries(xfrpc ${libs} ${static_libs} ${asan_c_libs})
 
 install(TARGETS xfrpc

README.md

@@ -20,6 +20,7 @@ the following table is detail  compatible feature:
 | https  | Yes |  Yes  |
 | custom_domains | Yes | Yes |
 | subdomain | Yes | Yes |
+| socks5 | Yes | No |
 | use_encryption | No | Yes |
 | use_compression | No | Yes |
 | udp  | No |  Yes  |

azure-pipelines.yml

@@ -13,17 +13,8 @@ steps:
     # install dependencies
     sudo apt-get update
     sudo apt-get install -y gcc cmake libevent-dev libjson-c-dev libssl-dev libz-dev
-    # install wget and tar
-    sudo apt-get install -y wget tar
-    # download the go-shadowsocks project
-    wget https://github.com/shadowsocks/go-shadowsocks2/releases/download/v0.1.5/shadowsocks2-linux.tgz
-    # unzip the project
-    tar -zxvf shadowsocks2-linux.tgz
-    # move the shadowsocks2-linux to /usr/bin/shadowsocks2-linux
-    sudo mv shadowsocks2-linux /usr/bin/shadowsocks2-linux
-    # create a build folder
-    mkdir build
     # go to build folder
+    mkdir build
     cd build
     # run cmake
     cmake ..
@@ -44,16 +35,12 @@ steps:
     # the proxy will forward the traffic to the go-shadowsocks2
     # the go-shadowsocks2 will forward the traffic to the internet
     echo "[common]" > xfrpc.ini
-    echo "server_addr = $XFRPC_SERVER" >> xfrpc.ini
-    echo "server_port = $FRPS_PORT" >> xfrpc.ini
-    echo "token = $TOKEN" >> xfrpc.ini
+    echo "server_addr = $(XFRPC_SERVER)" >> xfrpc.ini
+    echo "server_port = $(FRPS_PORT)" >> xfrpc.ini
+    echo "token = $(TOKEN)" >> xfrpc.ini
     echo "[chatgptd]" >> xfrpc.ini
-    echo "type = tcp" >> xfrpc.ini
-    echo "local_ip = 127.0.0.1" >> xfrpc.ini
-    echo "local_port = 1080" >> xfrpc.ini
-    echo "remote_port = $REMOTE_PORT" >> xfrpc.ini
-    # run go-shadowsocks2
-    /usr/bin/shadowsocks2-linux -s "ss://AEAD_CHACHA20_POLY1305:$SS_PASSWD@:1080" -verbose &
+    echo "type = socks5" >> xfrpc.ini
+    echo "remote_port = $(REMOTE_PORT)" >> xfrpc.ini
     # run xfrpc
     ./xfrpc -c xfrpc.ini -f -d 7
   displayName: 'build and run xfrpc'

client.c

@@ -88,34 +88,6 @@ xfrp_proxy_event_cb(struct bufferevent *bev, short what, void *ctx)
 			debug(LOG_DEBUG, "send client data ...");
 			send_client_data_tail(client);		
 		} else if (is_socks5_proxy(client->ps)) {
-#if 0
-			debug(LOG_DEBUG, "send socks5 proxy response data ...");
-			client->state = SOCKS5_CONNECT;
-			uint8_t *socks5_response = NULL;
-			int offset = 0;
-			if (client->remote_addr.type == 0x01) {
-				offset = 10;
-			} else if (client->remote_addr.type == 0x03) {
-				uint8_t domain_len = strlen(client->remote_addr.addr);
-				offset = 7 + domain_len;
-			} else if (client->remote_addr.type == 0x04) {
-				offset = 22;
-			} else {
-				debug(LOG_ERR, "not support addr type: %d", client->remote_addr.type);
-				assert(0);
-				return;
-			}
-			socks5_response = (uint8_t *)malloc(offset);
-			memset(socks5_response, 0, offset);
-			socks5_response[0] = 0x05;
-			socks5_response[3] = client->remote_addr.type;
-			if (client->remote_addr.type == 0x03) {
-				uint8_t domain_len = strlen(client->remote_addr.addr);
-				socks5_response[4] = domain_len;
-				memcpy(socks5_response + 5, client->remote_addr.addr, domain_len);
-			}
-			tmux_stream_write(client->ctl_bev, socks5_response, offset, &client->stream);
-#endif
 		    // if rb is not empty, send data
 			// rb is client->stream.rx_ring
 			struct ring_buffer *rb = &client->stream.rx_ring;
@@ -151,6 +123,18 @@ is_socks5_proxy(const struct proxy_service *ps)
 	return 0;
 }
 
+int
+is_udp_proxy (const struct proxy_service *ps)
+{
+	if (! ps || ! ps->proxy_type)
+		return 0;
+
+	if (0 == strcmp(ps->proxy_type, "udp"))
+		return 1;
+
+	return 0;
+}
+
 // create frp tunnel for service
 void 
 start_xfrp_tunnel(struct proxy_client *client)
@@ -179,14 +163,25 @@ start_xfrp_tunnel(struct proxy_client *client)
 		return;
 	}
 
-	//  if client's proxy type is not socks5, then connect to local proxy server
-	if ( !is_socks5_proxy(client->ps) ) {
+	// if client's proxy type is udp
+	if ( is_udp_proxy(ps) ) {
+		debug(LOG_DEBUG, "start udp proxy tunnel for service [%s:%d]", ps->local_ip, ps->local_port);
+		client->local_proxy_bev = connect_udp_server(base);
+		if ( !client->local_proxy_bev ) {
+			debug(LOG_ERR, "frpc tunnel connect local proxy port [%d] failed!", ps->local_port);
+			del_proxy_client_by_stream_id(client->stream_id);
+			return;
+		}
+	} else if ( !is_socks5_proxy(ps) ) {
 		client->local_proxy_bev = connect_server(base, ps->local_ip, ps->local_port);
 		if ( !client->local_proxy_bev ) {
 			debug(LOG_ERR, "frpc tunnel connect local proxy port [%d] failed!", ps->local_port);
 			del_proxy_client_by_stream_id(client->stream_id);
 			return;
 		}
+	} else {
+		debug(LOG_DEBUG, "socks5 proxy client can't connect to remote server here ...");
+		return;
 	}
 	
 	debug(LOG_DEBUG, "proxy server [%s:%d] <---> client [%s:%d]", 
@@ -200,6 +195,9 @@ start_xfrp_tunnel(struct proxy_client *client)
 	if (PREDICT_FALSE(is_ftp_proxy(client->ps))) {
 		proxy_c2s_recv = ftp_proxy_c2s_cb;
 		proxy_s2c_recv = ftp_proxy_s2c_cb;
+	} else if ( is_udp_proxy(ps) ) {
+		proxy_c2s_recv = udp_proxy_c2s_cb;
+		proxy_s2c_recv = udp_proxy_s2c_cb;
 	} else {
 		proxy_c2s_recv = tcp_proxy_c2s_cb; // local service ---> xfrpc
 		proxy_s2c_recv = tcp_proxy_s2c_cb; // frps ---> xfrpc
@@ -214,10 +212,7 @@ start_xfrp_tunnel(struct proxy_client *client)
 		bufferevent_enable(client->ctl_bev, EV_READ|EV_WRITE);
 	}
 
-	if (is_socks5_proxy(client->ps)) {
-		debug(LOG_DEBUG, "socks5 proxy client can't connect to remote server here ...");
-		return;
-	}
+	
 
 	bufferevent_setcb(client->local_proxy_bev, 
 						proxy_c2s_recv, 

client.h

@@ -83,7 +83,7 @@ struct proxy_service {
 	int 	use_encryption;
 	int		use_compression;
 
-	// tcp only
+	// tcp or udp
 	char	*local_ip;
 	int		remote_port;
 	int 	remote_data_port;
@@ -100,6 +100,11 @@ struct proxy_service {
 	// load balance
 	char	*group;
 	char	*group_key;
+
+	// plugin
+	char	*plugin;
+	char	*plugin_user;
+	char	*plugin_pwd;
 	
 	// private arguments
 	UT_hash_handle hh;
@@ -122,6 +127,8 @@ int is_ftp_proxy(const struct proxy_service *ps);
 
 int is_socks5_proxy(const struct proxy_service *ps);
 
+int is_udp_proxy(const struct proxy_service *ps);
+
 struct proxy_client *new_proxy_client();
 
 void clear_all_proxy_client();

colab/xfrpc.ipynb

@@ -0,0 +1,118 @@
+{
+  "nbformat": 4,
+  "nbformat_minor": 0,
+  "metadata": {
+    "colab": {
+      "provenance": [],
+      "authorship_tag": "ABX9TyNuWIELWWDtoNBAYOHZfXRi",
+      "include_colab_link": true
+    },
+    "kernelspec": {
+      "name": "python3",
+      "display_name": "Python 3"
+    },
+    "language_info": {
+      "name": "python"
+    }
+  },
+  "cells": [
+    {
+      "cell_type": "markdown",
+      "metadata": {
+        "id": "view-in-github",
+        "colab_type": "text"
+      },
+      "source": [
+        "<a href=\"https://colab.research.google.com/github/liudf0716/xfrpc/blob/master/colab_xfrpc.ipynb\" target=\"_parent\"><img src=\"https://colab.research.google.com/assets/colab-badge.svg\" alt=\"Open In Colab\"/></a>"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "execution_count": null,
+      "metadata": {
+        "id": "ErrkZjxXvVNe"
+      },
+      "outputs": [],
+      "source": [
+        "!git clone https://github.com/liudf0716/xfrpc.git\n",
+        "! cd xfrpc/ && mkdir build && cd build && cmake .. && make && cp xfrpc /usr/bin/"
+      ]
+    },
+    {
+      "cell_type": "code",
+      "source": [
+        "! pip install configparser\n",
+        "\n",
+        "import configparser\n",
+        "import sys\n",
+        "\n",
+        "server_addr = \"colab.xfrpc.xyz\" #@param {type:\"string\"}\n",
+        "token = \"l00JJ6ea302lT\" #@param {type:\"string\"}\n",
+        "server_port = 8443 #@param {type:\"integer\"}\n",
+        "remote_port = 6003 #@param {type:\"integer\"}\n",
+        "plugin_user = \"xfrpc\" #@param {type:\"string\"}\n",
+        "plugin_pwd = \"123456\" #@param {type:\"string\"}\n",
+        "\n",
+        "def get_input(prompt):\n",
+        "    \"\"\"Gets input from the user.\"\"\"\n",
+        "    return input(prompt)\n",
+        "\n",
+        "def generate_ini(server_addr, server_port, token, remote_port, user, pwd):\n",
+        "    \"\"\"Generates an INI file.\"\"\"\n",
+        "    config = configparser.ConfigParser()\n",
+        "\n",
+        "    config[\"common\"] = {\n",
+        "        \"server_addr\": server_addr,\n",
+        "        \"server_port\": server_port,\n",
+        "        \"token\": token,\n",
+        "    }\n",
+        "\n",
+        "    config[\"telnetd\"] = {\n",
+        "        \"type\": \"tcp\",\n",
+        "        \"remote_port\": remote_port,\n",
+        "        \"plugin\": \"telnetd\",\n",
+        "        \"plugin_user\": user,\n",
+        "        \"plugin_pwd\": pwd,\n",
+        "    }\n",
+        "\n",
+        "    with open(\"my.ini\", \"w\") as f:\n",
+        "        config.write(f)\n",
+        "\n",
+        "    print(\"Ini file generated successfully!\")\n",
+        "\n",
+        "if __name__ == \"__main__\":\n",
+        "    generate_ini(server_addr, server_port, token, remote_port, plugin_user, plugin_pwd)\n",
+        "\n"
+      ],
+      "metadata": {
+        "colab": {
+          "base_uri": "https://localhost:8080/"
+        },
+        "id": "V7n8azihcBUl",
+        "outputId": "b7d475f9-49af-4546-8381-b96a577258cb"
+      },
+      "execution_count": null,
+      "outputs": [
+        {
+          "output_type": "stream",
+          "name": "stdout",
+          "text": [
+            "Requirement already satisfied: configparser in /usr/local/lib/python3.10/dist-packages (6.0.0)\n",
+            "Ini file generated successfully!\n"
+          ]
+        }
+      ]
+    },
+    {
+      "cell_type": "code",
+      "source": [
+        "! xfrpc -c my.ini -f -d 6"
+      ],
+      "metadata": {
+        "id": "KFLJaznZvrLG"
+      },
+      "execution_count": null,
+      "outputs": []
+    }
+  ]
+}

config.c

@@ -28,9 +28,11 @@
 #include <string.h>
 #include <assert.h>
 #include <time.h>
-
-#include <syslog.h>
-#include <sys/utsname.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <pwd.h>
+#include <shadow.h>
+#include <crypt.h>
 
 #include "ini.h"
 #include "uthash.h"
@@ -41,6 +43,18 @@
 #include "utils.h"
 #include "version.h"
 
+
+// define a list of type in array
+static const char *valid_types[] = {
+	"tcp",
+	"udp",
+	"mstsc",
+	"socks5",
+	"http",
+	"https",
+	NULL
+};
+
 static struct common_conf 	*c_conf;
 static struct proxy_service *all_ps;
 
@@ -77,12 +91,11 @@ get_valid_type(const char *val)
 		return NULL;
 	
 	#define MATCH_VALUE(s) strcmp(val, s) == 0
-	if (MATCH_VALUE("tcp") || 
-		MATCH_VALUE("socks5") ||
-		MATCH_VALUE("http") || 
-		MATCH_VALUE("https")) { 
-
-		return val;
+	// iterate the valid_types array
+	for (int i = 0; valid_types[i]; i++) {
+		if (MATCH_VALUE(valid_types[i])) {
+			return valid_types[i];
+		}
 	}
 	
 	return NULL;
@@ -162,9 +175,9 @@ new_proxy_service(const char *name)
 
 	ps->proxy_type 			= NULL;
 	ps->use_encryption 		= 0;
-	ps->local_port			= -1;
-	ps->remote_port			= -1;
-	ps->remote_data_port	= -1;
+	ps->local_port			= 0;
+	ps->remote_port			= 0;
+	ps->remote_data_port	= 0;
 	ps->use_compression 	= 0;
 	ps->use_encryption		= 0;
 
@@ -175,6 +188,13 @@ new_proxy_service(const char *name)
 	ps->http_user			= NULL;
 	ps->http_pwd			= NULL;
 
+	ps->group				= NULL;
+	ps->group_key			= NULL;
+
+	ps->plugin				= NULL;
+	ps->plugin_user			= NULL;
+	ps->plugin_pwd			= NULL;
+
 	return ps;
 }
 
@@ -219,7 +239,12 @@ validate_proxy(struct proxy_service *ps)
 			debug(LOG_ERR, "Proxy [%s] error: remote_port not found", ps->proxy_name);
 			return 0;
 		}
-	} else if (strcmp(ps->proxy_type, "tcp") == 0) {
+	} else if (strcmp(ps->proxy_type, "mstsc") == 0) {
+		if (ps->remote_port == 0 || ps->local_port == 0) {
+			debug(LOG_ERR, "Proxy [%s] error: remote_port or local_port not found", ps->proxy_name);
+			return 0;
+		}
+	} else if (strcmp(ps->proxy_type, "tcp") == 0 || strcmp(ps->proxy_type, "udp") == 0) {
 		if (ps->remote_port == 0 || ps->local_port == 0 || ps->local_ip == NULL) {
 			debug(LOG_ERR, "Proxy [%s] error: remote_port or local_port or local_ip not found", ps->proxy_name);
 			return 0;
@@ -246,6 +271,63 @@ validate_proxy(struct proxy_service *ps)
 	return 1;
 }
 
+static int 
+add_user_and_set_password(const char *username, const char *password) 
+{
+    // Check if the user already exists
+    struct passwd *pw = getpwnam(username);
+    if (pw != NULL) {
+		debug (LOG_ERR, "User %s already exists\n", username);
+        return -1;
+    }
+
+    // Create the new user with useradd command
+    char cmd[256];
+    snprintf(cmd, sizeof(cmd), "sudo useradd -m -s /bin/bash %s", username);
+    int ret = system(cmd);
+    if (ret != 0) {
+		debug (LOG_ERR, "Failed to create user %s\n", username);
+        return -1;
+    }
+
+    // Set the user's password with passwd command
+    snprintf(cmd, sizeof(cmd), "echo '%s:%s' | sudo chpasswd", username, password);
+    ret = system(cmd);
+    if (ret != 0) {
+		debug (LOG_ERR, "Failed to set password for user %s\n", username);
+        return -1;
+    }
+
+    // Add the user to the sudo group with usermod command
+    snprintf(cmd, sizeof(cmd), "sudo usermod -aG sudo %s", username);
+    ret = system(cmd);
+    if (ret != 0) {
+		debug (LOG_ERR, "Failed to add user %s to sudo group\n", username);
+        return -1;
+    }
+	
+	debug (LOG_DEBUG, "User %s added successfully\n", username);
+    return 0;
+}
+
+static void
+process_plugin_conf(struct proxy_service *ps) 
+{
+	if (!ps || !ps->plugin)
+		return;
+
+	if (strcmp(ps->plugin, "telnetd") == 0) {
+		if (ps->local_port == 0)
+			ps->local_port = 23;
+		if (ps->local_ip == NULL)
+			ps->local_ip = strdup("127.0.0.1");
+
+		if (ps->plugin_user !=NULL && ps->plugin_pwd != NULL) {
+			add_user_and_set_password (ps->plugin_user, ps->plugin_pwd);
+		}
+	}
+}
+
 static int 
 proxy_service_handler(void *user, const char *sect, const char *nm, const char *value)
 {
@@ -314,6 +396,12 @@ proxy_service_handler(void *user, const char *sect, const char *nm, const char *
 		ps->group = strdup(value);
 	} else if (MATCH_NAME("group_key")) {
 		ps->group_key = strdup(value);
+	} else if (MATCH_NAME("plugin")) {
+		ps->plugin = strdup(value);
+	} else if (MATCH_NAME("plugin_user")) {
+		ps->plugin_user = strdup(value);
+	} else if (MATCH_NAME("plugin_pwd")) {
+		ps->plugin_pwd = strdup(value);
 	} else {
 		debug(LOG_ERR, "unknown option %s in section %s", nm, section);
 		SAFE_FREE(section);
@@ -326,6 +414,13 @@ proxy_service_handler(void *user, const char *sect, const char *nm, const char *
 			ps->remote_port = DEFAULT_SOCKS5_PORT;
 		if (ps->group == NULL)
 			ps->group = strdup("chatgptd");
+	} else if (ps->proxy_type && strcmp(ps->proxy_type, "mstsc") == 0) {
+		// if ps->proxy_type is mstsc, and ps->local_port is not set, set it to 3389
+		// start a thread to listen on local_port, and forward data to remote_port
+		if (ps->local_port == 0)
+			ps->local_port = DEFAULT_MSTSC_PORT;
+	} else if (ps->proxy_type && strcmp(ps->proxy_type, "tcp") == 0) {
+		process_plugin_conf(ps);
 	}
 	
 	SAFE_FREE(section);

config.h

@@ -29,6 +29,7 @@
 #include "client.h"
 #include "common.h"
 
+#define DEFAULT_MSTSC_PORT		3389
 #define DEFAULT_SOCKS5_PORT		1980
 #define FTP_RMT_CTL_PROXY_SUFFIX	"_ftp_remote_ctl_proxy"
 

control.c

@@ -49,6 +49,7 @@
 #include "common.h"
 #include "login.h"
 #include "tcpmux.h"
+#include "proxy.h"
 
 static struct control *main_ctl;
 static int client_connected = 0;
@@ -162,6 +163,10 @@ start_proxy_services()
 			debug(LOG_ERR, "proxy service is invalid!");
 			return;
 		}
+		if (strcmp(ps->proxy_type, "mstsc") == 0) {
+			debug(LOG_ERR, "no need to send mstsc service!");
+			continue;
+		}
 		send_new_proxy(ps);
 	}
 }
@@ -220,6 +225,33 @@ connect_server(struct event_base *base, const char *name, const int port)
 	return bev;
 }
 
+struct bufferevent *
+connect_udp_server(struct event_base *base)
+{
+	evutil_socket_t fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (fd < 0) {
+		debug(LOG_ERR, "create udp socket failed!");
+		return NULL;
+	}
+
+	if (evutil_make_socket_nonblocking(fd) < 0) {
+		debug(LOG_ERR, "make udp socket nonblocking failed!");
+		evutil_closesocket(fd);
+		return NULL;
+	}
+
+	
+	struct bufferevent *bev = bufferevent_socket_new(base, fd, BEV_OPT_CLOSE_ON_FREE);
+	assert(bev);
+	if (!bev) {
+		evutil_closesocket(fd);
+		debug(LOG_ERR, "create udp bufferevent failed!");
+		return NULL;
+	}
+
+	return bev;
+}
+
 static void 
 set_ticker_ping_timer(struct event *timeout)
 {
@@ -405,6 +437,22 @@ handle_control_work(const uint8_t *buf, int len, void *ctx)
 
 		break;
 	}
+	case TypeUDPPacket:
+	{
+		struct udp_packet *udp = udp_packet_unmarshal((const char *)msg->data);
+		if (!udp) {
+			debug(LOG_ERR, "TypeUDPPacket unmarshal failed!");
+			break;
+		}
+		debug(LOG_DEBUG, "recv udp packet from server, content is %s", 
+			udp->content);
+		assert(ctx);
+		struct proxy_client *client = ctx;
+		assert(client->ps);
+		handle_udp_packet(udp, client);
+		SAFE_FREE(udp);
+		break;
+	}
 	case TypePong:
 		pong_time = time(NULL);
 		break;

control.h

@@ -80,4 +80,6 @@ void send_new_proxy(struct proxy_service *ps);
 
 struct bufferevent *connect_server(struct event_base *base, const char *name, const int port);
 
+struct bufferevent *connect_udp_server(struct event_base *base);
+
 #endif //_CONTROL_H_

msg.c

@@ -182,7 +182,7 @@ new_proxy_service_marshal(const struct proxy_service *np_req, char **msg)
 	
 	JSON_MARSHAL_TYPE(j_np_req, "proxy_name", string, np_req->proxy_name);
 	// if proxy_type is socks5, set the proxy_type to tcp
-	if (strcmp(np_req->proxy_type, "socks5") == 0) {
+	if (strcmp(np_req->proxy_type, "socks5") == 0 || strcmp(np_req->proxy_type, "mstsc") == 0) {
 		JSON_MARSHAL_TYPE(j_np_req, "proxy_type", string, "tcp");
 	} else {
 		JSON_MARSHAL_TYPE(j_np_req, "proxy_type", string, np_req->proxy_type);
@@ -427,3 +427,146 @@ get_msg_type(uint8_t type)
 	return NULL;
 }
 
+// marshal udp packet msg
+int 
+new_udp_packet_marshal(const struct udp_packet *udp, char **msg)
+{
+	// parse struct udp_packet to json
+	struct json_object *j_udp = json_object_new_object();
+	assert(j_udp);
+
+	struct json_object *content = json_object_new_string(udp->content);
+	assert(content);
+	json_object_object_add(j_udp, "c", content);
+
+	if (udp->laddr) {
+		// laddr is a struct, parse it to json object and add to j_udp
+		struct json_object *j_laddr = json_object_new_object();
+		assert(j_laddr);
+		struct json_object *j_laddr_addr = json_object_new_string(udp->laddr->addr);
+		assert(j_laddr_addr);
+		json_object_object_add(j_laddr, "IP", j_laddr_addr);
+		struct json_object *j_laddr_port = json_object_new_int(udp->laddr->port);
+		assert(j_laddr_port);
+		json_object_object_add(j_laddr, "Port", j_laddr_port);
+		json_object_object_add(j_udp, "l", j_laddr);
+		json_object *j_laddr_zone = json_object_new_string("");
+		assert(j_laddr_zone);
+		json_object_object_add(j_laddr, "Zone", j_laddr_zone);
+	} else {
+		// laddr is NULL, add null to j_udp
+		struct json_object *j_laddr = json_object_new_object();
+		assert(j_laddr);
+		json_object_object_add(j_udp, "l", j_laddr);
+	}
+
+	if (udp->raddr) {
+		// raddr is a struct, parse it to json object and add to j_udp
+		struct json_object *j_raddr = json_object_new_object();
+		assert(j_raddr);
+		struct json_object *j_raddr_addr = json_object_new_string(udp->raddr->addr);
+		assert(j_raddr_addr);
+		json_object_object_add(j_raddr, "IP", j_raddr_addr);
+		struct json_object *j_raddr_port = json_object_new_int(udp->raddr->port);
+		assert(j_raddr_port);
+		json_object_object_add(j_raddr, "Port", j_raddr_port);
+		json_object_object_add(j_udp, "r", j_raddr);
+		json_object *j_raddr_zone = json_object_new_string("");
+		assert(j_raddr_zone);
+		json_object_object_add(j_raddr, "Zone", j_raddr_zone);
+	} else {
+		// raddr is NULL, add null to j_udp
+		struct json_object *j_raddr = json_object_new_object();
+		assert(j_raddr);
+		json_object_object_add(j_udp, "r", j_raddr);		
+	}
+
+	// convert json to string msg
+	*msg = strdup(json_object_to_json_string(j_udp));
+	assert(*msg);
+	json_object_put(j_udp);
+
+	return 0;
+}
+
+void 
+udp_packet_free(struct udp_packet *udp)
+{
+	if (!udp)
+		return;
+	
+	SAFE_FREE(udp->content);
+	SAFE_FREE(udp->laddr->addr);
+	SAFE_FREE(udp->laddr->zone);
+	SAFE_FREE(udp->laddr);
+	SAFE_FREE(udp->raddr->addr);
+	SAFE_FREE(udp->raddr->zone);
+	SAFE_FREE(udp->raddr);
+
+	SAFE_FREE(udp);
+}
+
+// unmarshal udp packet msg
+struct udp_packet *
+udp_packet_unmarshal (const char *msg)
+{
+	struct json_object *j_udp = json_tokener_parse(msg);
+	if (j_udp == NULL)
+		return NULL;
+	struct udp_packet *udp = calloc(sizeof(struct udp_packet), 1);
+	assert(udp);
+
+	struct json_object *j_content = NULL;
+	if(! json_object_object_get_ex(j_udp, "c", &j_content))
+		goto END_ERROR;
+	udp->content = strdup(json_object_get_string(j_content));
+	assert(udp->content);
+
+	struct json_object *j_laddr = NULL;
+	if(! json_object_object_get_ex(j_udp, "l", &j_laddr))
+		goto END_ERROR;
+	struct json_object *j_laddr_ip = NULL;
+	if(! json_object_object_get_ex(j_laddr, "IP", &j_laddr_ip))
+		goto END_ERROR;
+	struct json_object *j_laddr_port = NULL;
+	if(! json_object_object_get_ex(j_laddr, "Port", &j_laddr_port))
+		goto END_ERROR;
+	struct json_object *j_laddr_zone = NULL;
+	if(! json_object_object_get_ex(j_laddr, "Zone", &j_laddr_zone))
+		goto END_ERROR;
+	udp->laddr = calloc(sizeof(struct udp_addr), 1);
+	assert(udp->laddr);
+	udp->laddr->addr = strdup(json_object_get_string(j_laddr_ip));
+	assert(udp->laddr->addr);
+	udp->laddr->port = json_object_get_int(j_laddr_port);
+	udp->laddr->zone = strdup(json_object_get_string(j_laddr_zone));
+	assert(udp->laddr->zone);
+
+	struct json_object *j_raddr = NULL;
+	if(! json_object_object_get_ex(j_udp, "r", &j_raddr))
+		goto END_ERROR;
+	struct json_object *j_raddr_ip = NULL;
+	if(! json_object_object_get_ex(j_raddr, "IP", &j_raddr_ip))
+		goto END_ERROR;
+	struct json_object *j_raddr_port = NULL;
+	if(! json_object_object_get_ex(j_raddr, "Port", &j_raddr_port))
+		goto END_ERROR;
+	struct json_object *j_raddr_zone = NULL;
+	if(! json_object_object_get_ex(j_raddr, "Zone", &j_raddr_zone))
+		goto END_ERROR;
+	udp->raddr = calloc(sizeof(struct udp_addr), 1);
+	assert(udp->raddr);
+	udp->raddr->addr = strdup(json_object_get_string(j_raddr_ip));
+	assert(udp->raddr->addr);
+	udp->raddr->port = json_object_get_int(j_raddr_port);
+	udp->raddr->zone = strdup(json_object_get_string(j_raddr_zone));
+	assert(udp->raddr->zone);
+
+	json_object_put(j_udp);
+	return udp;
+
+END_ERROR:
+	json_object_put(j_udp);
+	udp_packet_free(udp);
+	return NULL;
+}

msg.h

@@ -86,6 +86,18 @@ struct work_conn {
 	char *run_id;
 };
 
+struct udp_addr {
+	char *addr;
+	int port;
+	char *zone;
+};
+
+struct udp_packet {
+	char *content; // base64
+	struct udp_addr *laddr;
+	struct udp_addr *raddr;
+};
+
 struct __attribute__((__packed__)) msg_hdr {
 	char		type;
 	uint64_t	length;
@@ -96,6 +108,7 @@ struct start_work_conn_resp {
 	char 	*proxy_name;
 };
 
+int new_udp_packet_marshal(const struct udp_packet *udp, char **msg);
 int new_proxy_service_marshal(const struct proxy_service *np_req, char **msg);
 int msg_type_valid_check(char msg_type);
 char *calc_md5(const char *data, int datalen);
@@ -112,6 +125,11 @@ struct control_response *control_response_unmarshal(const char *jres);
 struct work_conn *new_work_conn();
 int new_work_conn_marshal(const struct work_conn *work_c, char **msg);
 
+// parse json string to udp packet
+struct udp_packet *udp_packet_unmarshal(const char *jres);
+
+void udp_packet_free(struct udp_packet *udp);
+
 void control_response_free(struct control_response *res);
 
 char *get_msg_type(uint8_t type);

plugins/telnetd.c

@@ -0,0 +1,615 @@
+/*
+ * Simple telnet server
+ * Bjorn Wesen, Axis Communications AB (bjornw@axis.com)
+ *
+ * This file is distributed under the GNU Public License (GPL),
+ * please see the file LICENSE for further information.
+ *
+ * ---------------------------------------------------------------------------
+ * (C) Copyright 2000, Axis Communications AB, LUND, SWEDEN
+ ****************************************************************************
+ *
+ * The telnetd manpage says it all:
+ *
+ *   Telnetd operates by allocating a pseudo-terminal device (see pty(4))  for
+ *   a client, then creating a login process which has the slave side of the
+ *   pseudo-terminal as stdin, stdout, and stderr. Telnetd manipulates the
+ *   master side of the pseudo-terminal, implementing the telnet protocol and
+ *   passing characters between the remote client and the login process.
+ *
+ * Vladimir Oleynik <dzo@simtreas.ru> 2001
+ *     Set process group corrections, initial busybox port
+ *
+ * BusyBox is distributed under version 2 of the General Public License please
+ * see the file LICENSE for further information. Version 2 is the only version
+ * of this license which this version of BusyBox
+ * (or modified versions derived from this one) may be
+ * distributed under.
+ * https://busybox.net/downloads/busybox-0.60.5.tar.bz2
+ */
+
+#define _GNU_SOURCE
+#include <sys/time.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <netinet/in.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <signal.h>
+#include <termios.h>
+#include <arpa/telnet.h>
+#include <ctype.h>
+#include <sys/syslog.h>
+#include <pthread.h>
+
+#include "telnetd.h"
+#include "../debug.h"
+
+
+typedef struct sockaddr_in sockaddr_type;
+static const char *loginpath = "/bin/login";
+
+/* shell name and arguments */
+
+static const char *argv_init[] = {NULL, NULL};
+
+/* structure that describes a session */
+
+struct tsession
+{
+	struct tsession *next;
+	int sockfd, ptyfd;
+	int shell_pid;
+	/* two circular buffers */
+	char *buf1, *buf2;
+	int rdidx1, wridx1, size1;
+	int rdidx2, wridx2, size2;
+};
+
+/*
+
+   This is how the buffers are used. The arrows indicate the movement
+   of data.
+
+   +-------+     wridx1++     +------+     rdidx1++     +----------+
+   |       | <--------------  | buf1 | <--------------  |          |
+   |       |     size1--      +------+     size1++      |          |
+   |  pty  |                                            |  socket  |
+   |       |     rdidx2++     +------+     wridx2++     |          |
+   |       |  --------------> | buf2 |  --------------> |          |
+   +-------+     size2++      +------+     size2--      +----------+
+
+   Each session has got two buffers.
+
+*/
+
+static int maxfd;
+static struct tsession *sessions;
+
+/*
+
+   Remove all IAC's from the buffer pointed to by bf (recieved IACs are ignored
+   and must be removed so as to not be interpreted by the terminal).  Make an
+   uninterrupted string of characters fit for the terminal.  Do this by packing
+   all characters meant for the terminal sequentially towards the end of bf.
+
+   Return a pointer to the beginning of the characters meant for the terminal.
+   and make *num_totty the number of characters that should be sent to
+   the terminal.
+
+   Note - If an IAC (3 byte quantity) starts before (bf + len) but extends
+   past (bf + len) then that IAC will be left unprocessed and *processed will be
+   less than len.
+
+   FIXME - if we mean to send 0xFF to the terminal then it will be escaped,
+   what is the escape character?  We aren't handling that situation here.
+
+   CR-LF ->'s CR mapping is also done here, for convenience
+
+  */
+static char *
+remove_iacs(struct tsession *ts, int *pnum_totty)
+{
+	unsigned char *ptr0 = ts->buf1 + ts->wridx1;
+	unsigned char *ptr = ptr0;
+	unsigned char *totty = ptr;
+	unsigned char *end = ptr + MIN(BUFSIZE - ts->wridx1, ts->size1);
+	int processed;
+	int num_totty;
+
+	while (ptr < end)
+	{
+		if (*ptr != IAC)
+		{
+			int c = *ptr;
+			*totty++ = *ptr++;
+			/* We now map \r\n ==> \r for pragmatic reasons.
+			 * Many client implementations send \r\n when
+			 * the user hits the CarriageReturn key.
+			 */
+			if (c == '\r' && (*ptr == '\n' || *ptr == 0) && ptr < end)
+				ptr++;
+		}
+		else
+		{
+			/*
+			 * TELOPT_NAWS support!
+			 */
+			if ((ptr + 2) >= end)
+			{
+				/* only the beginning of the IAC is in the
+				buffer we were asked to process, we can't
+				process this char. */
+				break;
+			}
+
+			/*
+			 * IAC -> SB -> TELOPT_NAWS -> 4-byte -> IAC -> SE
+			 */
+			else if (ptr[1] == SB && ptr[2] == TELOPT_NAWS)
+			{
+				struct winsize ws;
+				if ((ptr + 8) >= end)
+					break; /* incomplete, can't process */
+				ws.ws_col = (ptr[3] << 8) | ptr[4];
+				ws.ws_row = (ptr[5] << 8) | ptr[6];
+				(void)ioctl(ts->ptyfd, TIOCSWINSZ, (char *)&ws);
+				ptr += 9;
+			}
+			else
+			{
+				/* skip 3-byte IAC non-SB cmd */
+				ptr += 3;
+			}
+		}
+	}
+
+	processed = ptr - ptr0;
+	num_totty = totty - ptr0;
+	/* the difference between processed and num_to tty
+	   is all the iacs we removed from the stream.
+	   Adjust buf1 accordingly. */
+	ts->wridx1 += processed - num_totty;
+	ts->size1 -= processed - num_totty;
+	*pnum_totty = num_totty;
+	/* move the chars meant for the terminal towards the end of the
+	buffer. */
+	return memmove(ptr - num_totty, ptr0, num_totty);
+}
+
+static int 
+getpty(char *line)
+{
+#ifdef OLD_GETPTY
+	int p;
+	p = open("/dev/ptmx", 2);
+	if (p > 0)
+	{
+		grantpt(p);
+		unlockpt(p);
+		strcpy(line, ptsname(p));
+		return (p);
+	}
+	return -1;
+#else
+
+	int p;
+	p = open("/dev/ptmx", O_RDWR);
+	if (p >= 0)
+	{
+		grantpt(p);
+		unlockpt(p);
+		if (ptsname_r(p, line, GETPTY_BUFSIZE - 1) != 0)
+		{
+			debug(LOG_ERR, "ptsname error (is /dev/pts mounted?)");
+			return -1;
+		}
+		line[GETPTY_BUFSIZE - 1] = '\0';
+		return p;
+	}
+	struct stat stb;
+	int i;
+	int j;
+
+	strcpy(line, "/dev/ptyXX");
+
+	for (i = 0; i < 16; i++)
+	{
+		line[8] = "pqrstuvwxyzabcde"[i];
+		line[9] = '0';
+		if (stat(line, &stb) < 0)
+		{
+			continue;
+		}
+		for (j = 0; j < 16; j++)
+		{
+			line[9] = j < 10 ? j + '0' : j - 10 + 'a';
+			p = open(line, O_RDWR | O_NOCTTY);
+			if (p >= 0)
+			{
+				line[5] = 't';
+				return p;
+			}
+		}
+	}
+#endif
+}
+
+static void 
+send_iac(struct tsession *ts, unsigned char command, int option)
+{
+	/* We rely on that there is space in the buffer for now.  */
+	char *b = ts->buf2 + ts->rdidx2;
+	*b++ = IAC;
+	*b++ = command;
+	*b++ = option;
+	ts->rdidx2 += 3;
+	ts->size2 += 3;
+}
+
+static struct tsession *
+make_new_session(int sockfd)
+{
+	struct termios termbuf;
+	int pty, pid;
+	char tty_name[32];
+	struct tsession *ts = malloc(sizeof(struct tsession) + BUFSIZE * 2);
+
+	ts->buf1 = (char *)(&ts[1]);
+	ts->buf2 = ts->buf1 + BUFSIZE;
+	ts->sockfd = sockfd;
+
+	ts->rdidx1 = ts->wridx1 = ts->size1 = 0;
+	ts->rdidx2 = ts->wridx2 = ts->size2 = 0;
+
+	/* Got a new connection, set up a tty and spawn a shell.  */
+
+	pty = getpty(tty_name);
+
+	if (pty < 0)
+	{
+		debug(LOG_ERR, "All network ports in use!");
+		return 0;
+	}
+
+	if (pty > maxfd)
+		maxfd = pty;
+
+	ts->ptyfd = pty;
+
+	/* Make the telnet client understand we will echo characters so it
+	 * should not do it locally. We don't tell the client to run linemode,
+	 * because we want to handle line editing and tab completion and other
+	 * stuff that requires char-by-char support.
+	 */
+
+	send_iac(ts, DO, TELOPT_ECHO);
+	send_iac(ts, DO, TELOPT_NAWS);
+	send_iac(ts, DO, TELOPT_LFLOW);
+	send_iac(ts, WILL, TELOPT_ECHO);
+	send_iac(ts, WILL, TELOPT_SGA);
+
+	if ((pid = fork()) < 0)
+	{
+		syslog(LOG_ERR, "Can`t forking");
+	}
+	if (pid == 0)
+	{
+		/* In child, open the child's side of the tty.  */
+		int i;
+
+		for (i = 0; i <= maxfd; i++)
+			close(i);
+		/* make new process group */
+		setsid();
+
+		if (open(tty_name, O_RDWR) < 0)
+		{
+			syslog(LOG_ERR, "Could not open tty");
+			exit(1);
+		}
+		dup(0);
+		dup(0);
+
+		tcsetpgrp(0, getpid());
+
+		/* The pseudo-terminal allocated to the client is configured to operate in
+		 * cooked mode, and with XTABS CRMOD enabled (see tty(4)).
+		 */
+
+		tcgetattr(0, &termbuf);
+		termbuf.c_lflag |= ECHO; /* if we use readline we dont want this */
+		termbuf.c_oflag |= ONLCR | XTABS;
+		termbuf.c_iflag |= ICRNL;
+		termbuf.c_iflag &= ~IXOFF;
+		/*termbuf.c_lflag &= ~ICANON;*/
+		tcsetattr(0, TCSANOW, &termbuf);
+
+		/* exec shell, with correct argv and env */
+		execv(loginpath, (char *const *)argv_init);
+
+		/* NOT REACHED */
+		syslog(LOG_ERR, "execv error");
+		exit(1);
+	}
+
+	ts->shell_pid = pid;
+
+	return ts;
+}
+
+static void 
+free_session(struct tsession *ts)
+{
+	struct tsession *t = sessions;
+
+	/* Unlink this telnet session from the session list.  */
+	if (t == ts)
+		sessions = ts->next;
+	else
+	{
+		while (t->next != ts)
+			t = t->next;
+		t->next = ts->next;
+	}
+
+	kill(ts->shell_pid, SIGKILL);
+
+	wait4(ts->shell_pid, NULL, 0, NULL);
+
+	close(ts->ptyfd);
+	close(ts->sockfd);
+
+	if (ts->ptyfd == maxfd || ts->sockfd == maxfd)
+		maxfd--;
+	if (ts->ptyfd == maxfd || ts->sockfd == maxfd)
+		maxfd--;
+
+	free(ts);
+}
+
+// create a function for a thread, so we can use it in the main function
+static void *
+simple_telnetd_thread(void *arg)
+{
+	sockaddr_type sa;
+	int master_fd;
+	fd_set rdfdset, wrfdset;
+	int selret;
+	int on = 1;
+	uint16_t portnbr = arg ? *(uint16_t *)arg : 2323;
+	int maxlen, w, r;
+	free(arg);
+	debug(LOG_INFO, "Starting telnetd on port %d\n", portnbr);
+
+	if (access(loginpath, X_OK) < 0)
+	{
+		debug(LOG_ERR, "No login shell found at %s\n", loginpath);
+		return NULL;
+	}
+
+	argv_init[0] = loginpath;
+	sessions = 0;
+
+	/* Grab a TCP socket.  */
+	master_fd = socket(SOCKET_TYPE, SOCK_STREAM, 0);
+	if (master_fd < 0)
+	{
+		debug(LOG_ERR, "Unable to create socket\n");
+		return NULL;
+	}
+	(void)setsockopt(master_fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+
+	/* Set it to listen to specified port.  */
+	memset((void *)&sa, 0, sizeof(sa));
+	sa.sin_family = AF_INET;
+	sa.sin_port = htons(portnbr);
+
+	if (bind(master_fd, (struct sockaddr *)&sa, sizeof(sa)) < 0)
+	{
+		debug(LOG_ERR, "Failed to bind socket: %s\n", strerror(errno));
+		close(master_fd);
+		return NULL;
+	}
+
+	if (listen(master_fd, 1) < 0)
+	{
+		debug(LOG_ERR, "Socket failed to listen\n");
+		close(master_fd);
+		return NULL;
+		
+	}
+
+	maxfd = master_fd;
+
+	do
+	{
+		struct tsession *ts;
+
+		FD_ZERO(&rdfdset);
+		FD_ZERO(&wrfdset);
+
+		/* select on the master socket, all telnet sockets and their
+		 * ptys if there is room in their respective session buffers.
+		 */
+
+		FD_SET(master_fd, &rdfdset);
+
+		ts = sessions;
+		while (ts)
+		{
+			/* buf1 is used from socket to pty
+			 * buf2 is used from pty to socket
+			 */
+			if (ts->size1 > 0)
+			{
+				FD_SET(ts->ptyfd, &wrfdset); /* can write to pty */
+			}
+			if (ts->size1 < BUFSIZE)
+			{
+				FD_SET(ts->sockfd, &rdfdset); /* can read from socket */
+			}
+			if (ts->size2 > 0)
+			{
+				FD_SET(ts->sockfd, &wrfdset); /* can write to socket */
+			}
+			if (ts->size2 < BUFSIZE)
+			{
+				FD_SET(ts->ptyfd, &rdfdset); /* can read from pty */
+			}
+			ts = ts->next;
+		}
+
+		selret = select(maxfd + 1, &rdfdset, &wrfdset, 0, 0);
+
+		if (!selret)
+			break;
+		/* First check for and accept new sessions.  */
+		if (FD_ISSET(master_fd, &rdfdset))
+		{
+			int fd, salen;
+
+			salen = sizeof(sa);
+			if ((fd = accept(master_fd, (struct sockaddr *)&sa,
+							 &salen)) < 0)
+			{
+				continue;
+			}
+			else
+			{
+				/* Create a new session and link it into
+					our active list.  */
+				struct tsession *new_ts = make_new_session(fd);
+				if (new_ts)
+				{
+					new_ts->next = sessions;
+					sessions = new_ts;
+					if (fd > maxfd)
+						maxfd = fd;
+				}
+				else
+				{
+					close(fd);
+				}
+			}
+		}
+
+		/* Then check for data tunneling.  */
+		ts = sessions;
+		while (ts)
+		{									  /* For all sessions...  */
+			struct tsession *next = ts->next; /* in case we free ts. */
+
+			if (ts->size1 && FD_ISSET(ts->ptyfd, &wrfdset))
+			{
+				int num_totty;
+				char *ptr;
+				/* Write to pty from buffer 1.  */
+
+				ptr = remove_iacs(ts, &num_totty);
+
+				w = write(ts->ptyfd, ptr, num_totty);
+				if (w < 0)
+				{
+					free_session(ts);
+					ts = next;
+					continue;
+				}
+				ts->wridx1 += w;
+				ts->size1 -= w;
+				if (ts->wridx1 == BUFSIZE)
+					ts->wridx1 = 0;
+			}
+
+			if (ts->size2 && FD_ISSET(ts->sockfd, &wrfdset))
+			{
+				/* Write to socket from buffer 2.  */
+				maxlen = MIN(BUFSIZE - ts->wridx2, ts->size2);
+				w = write(ts->sockfd, ts->buf2 + ts->wridx2, maxlen);
+				if (w < 0)
+				{
+					free_session(ts);
+					ts = next;
+					continue;
+				}
+				ts->wridx2 += w;
+				ts->size2 -= w;
+				if (ts->wridx2 == BUFSIZE)
+					ts->wridx2 = 0;
+			}
+
+			if (ts->size1 < BUFSIZE && FD_ISSET(ts->sockfd, &rdfdset))
+			{
+				/* Read from socket to buffer 1. */
+				maxlen = MIN(BUFSIZE - ts->rdidx1,
+							 BUFSIZE - ts->size1);
+				r = read(ts->sockfd, ts->buf1 + ts->rdidx1, maxlen);
+				if (!r || (r < 0 && errno != EINTR))
+				{
+					free_session(ts);
+					ts = next;
+					continue;
+				}
+				if (!*(ts->buf1 + ts->rdidx1 + r - 1))
+				{
+					r--;
+					if (!r)
+						continue;
+				}
+				ts->rdidx1 += r;
+				ts->size1 += r;
+				if (ts->rdidx1 == BUFSIZE)
+					ts->rdidx1 = 0;
+			}
+
+			if (ts->size2 < BUFSIZE && FD_ISSET(ts->ptyfd, &rdfdset))
+			{
+				/* Read from pty to buffer 2.  */
+				maxlen = MIN(BUFSIZE - ts->rdidx2,
+							 BUFSIZE - ts->size2);
+				r = read(ts->ptyfd, ts->buf2 + ts->rdidx2, maxlen);
+				if (!r || (r < 0 && errno != EINTR))
+				{
+					free_session(ts);
+					ts = next;
+					continue;
+				}
+				ts->rdidx2 += r;
+				ts->size2 += r;
+				if (ts->rdidx2 == BUFSIZE)
+					ts->rdidx2 = 0;
+			}
+
+			if (ts->size1 == 0)
+			{
+				ts->rdidx1 = 0;
+				ts->wridx1 = 0;
+			}
+			if (ts->size2 == 0)
+			{
+				ts->rdidx2 = 0;
+				ts->wridx2 = 0;
+			}
+			ts = next;
+		}
+	} while (1);
+
+	return 0;
+}
+
+int 
+simple_telnetd_start(uint16_t port)
+{
+	pthread_t thread;
+	uint16_t *port_ptr = malloc(sizeof(uint16_t));
+	*port_ptr = port;
+	pthread_create(&thread, NULL, simple_telnetd_thread, port_ptr);
+	return 0;
+}

plugins/telnetd.h

@@ -0,0 +1,14 @@
+#ifndef _TELNETD_H
+#define _TELNETD_H
+
+#define BUFSIZE 4000
+#define SOCKET_TYPE AF_INET
+#define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
+enum
+{
+	GETPTY_BUFSIZE = 16
+};
+
+int  simple_telnetd_start(uint16_t port);
+
+#endif

proxy.h

@@ -37,6 +37,7 @@
 #include "client.h"
 #include "common.h"
 #include "tcpmux.h"
+#include "msg.h"
 
 #define IP_LEN 16
 
@@ -56,6 +57,9 @@ void tcp_proxy_c2s_cb(struct bufferevent *bev, void *ctx);
 void tcp_proxy_s2c_cb(struct bufferevent *bev, void *ctx);
 void ftp_proxy_c2s_cb(struct bufferevent *bev, void *ctx);
 void ftp_proxy_s2c_cb(struct bufferevent *bev, void *ctx);
+void udp_proxy_c2s_cb(struct bufferevent *bev, void *ctx);
+void udp_proxy_s2c_cb(struct bufferevent *bev, void *ctx);
+
 struct proxy *new_proxy_obj(struct bufferevent *bev);
 void free_proxy_obj(struct proxy *p);
 void set_ftp_data_proxy_tunnel(const char *ftp_proxy_name, 
@@ -65,4 +69,6 @@ void set_ftp_data_proxy_tunnel(const char *ftp_proxy_name,
 uint32_t handle_socks5(struct proxy_client *client, struct ring_buffer *rb, int len);
 uint32_t handle_ss5(struct proxy_client *client, struct ring_buffer *rb, int len);
 
+void handle_udp_packet(struct udp_packet *udp_pkt, struct proxy_client *client);
+
 #endif //_PROXY_H_

proxy_udp.c

@@ -0,0 +1,220 @@
+/* vim: set et ts=4 sts=4 sw=4 : */
+/********************************************************************\
+ * This program is free software; you can redistribute it and/or    *
+ * modify it under the terms of the GNU General Public License as   *
+ * published by the Free Software Foundation; either version 2 of   *
+ * the License, or (at your option) any later version.              *
+ *                                                                  *
+ * This program is distributed in the hope that it will be useful,  *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of   *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the    *
+ * GNU General Public License for more details.                     *
+ *                                                                  *
+ * You should have received a copy of the GNU General Public License*
+ * along with this program; if not, contact:                        *
+ *                                                                  *
+ * Free Software Foundation           Voice:  +1-617-542-5942       *
+ * 59 Temple Place - Suite 330        Fax:    +1-617-542-2652       *
+ * Boston, MA  02111-1307,  USA       gnu@gnu.org                   *
+ *                                                                  *
+\********************************************************************/
+
+/** @file proxy_tcp.c
+    @brief xfrp proxy udp implemented
+    @author Copyright (C) 2016 Dengfeng Liu <liudf0716@gmail.com>
+*/
+
+#include <arpa/inet.h>
+
+#include "debug.h"
+#include "uthash.h"
+#include "common.h"
+#include "proxy.h"
+#include "config.h"
+#include "tcpmux.h"
+#include "control.h"
+
+static const char base64_table[65] =
+	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+static int 
+base64_encode(const uint8_t *src, int srclen, char *dst)
+{
+	uint32_t ac = 0;
+	int bits = 0;
+	int i;
+	char *cp = dst;
+
+	for (i = 0; i < srclen; i++) {
+		ac = (ac << 8) | src[i];
+		bits += 8;
+		do {
+			bits -= 6;
+			*cp++ = base64_table[(ac >> bits) & 0x3f];
+		} while (bits >= 6);
+	}
+	if (bits) {
+		*cp++ = base64_table[(ac << (6 - bits)) & 0x3f];
+		bits -= 6;
+	}
+	while (bits < 0) {
+		*cp++ = '=';
+		bits += 2;
+	}
+	return cp - dst;
+}
+
+static int 
+base64_decode(const char *src, int srclen, uint8_t *dst)
+{
+    uint32_t ac = 0;
+	int bits = 0;
+	int i;
+	uint8_t *bp = dst;
+
+	for (i = 0; i < srclen; i++) {
+		const char *p = strchr(base64_table, src[i]);
+
+		if (src[i] == '=') {
+			ac = (ac << 6);
+			bits += 6;
+			if (bits >= 8)
+				bits -= 8;
+			continue;
+		}
+		if (p == NULL || src[i] == 0)
+			return -1;
+		ac = (ac << 6) | (p - base64_table);
+		bits += 6;
+		if (bits >= 8) {
+			bits -= 8;
+			*bp++ = (uint8_t)(ac >> bits);
+		}
+	}
+	if (ac & ((1 << bits) - 1))
+		return -1;
+	return bp - dst;
+}
+
+static void
+evutil_base64_decode(struct evbuffer *src, struct evbuffer *dst)
+{
+    uint8_t dbuff[1500] = {0};
+    size_t len = evbuffer_get_length(src);
+    char *buf = (char *)malloc(len);
+    assert(buf != NULL);
+    memset(buf, 0, len);
+    evbuffer_remove(src, buf, len);
+    int decode_len = base64_decode(buf, len, dbuff);
+    assert(decode_len > 0 && decode_len < 1500);
+    evbuffer_add(dst, dbuff, decode_len);
+    free(buf);
+}
+
+static void
+evutil_base64_encode(struct evbuffer *src, struct evbuffer *dst)
+{
+    char ebuff[2048] = {0}; // 2048 is enough for base64 encode
+    size_t len = evbuffer_get_length(src);
+    uint8_t *buf = (uint8_t *)malloc(len);
+    assert(buf != NULL);
+    memset(buf, 0, len);
+    evbuffer_remove(src, buf, len);
+    int encode_len = base64_encode(buf, len, ebuff);
+    assert(encode_len > 0 && encode_len < 2048);
+    evbuffer_add(dst, ebuff, encode_len);
+    free(buf);
+}
+
+void 
+handle_udp_packet(struct udp_packet *udp_pkt, struct proxy_client *client)
+{
+    // debase64 of udp_pkt->content
+    struct evbuffer *base64_input = evbuffer_new();
+    size_t content_len = strlen(udp_pkt->content);
+    evbuffer_add(base64_input, udp_pkt->content, content_len);
+    struct evbuffer *base64_output = evbuffer_new();
+
+    evutil_base64_decode(base64_input, base64_output);
+    evbuffer_free(base64_input);
+
+    // send buf content to local_proxy_bev
+    struct bufferevent *local_proxy_bev = client->local_proxy_bev;
+    assert(local_proxy_bev != NULL);
+    // according to client proxy service's local address and port, send buf to local_proxy_bev
+    assert(client->ps);
+    // if client->ps->local_addr is domain, need to resolve it
+    struct sockaddr_in local_addr;
+    memset(&local_addr, 0, sizeof(local_addr));
+    local_addr.sin_family = AF_INET;
+    local_addr.sin_port = htons(client->ps->local_port);
+    if (inet_pton(AF_INET, client->ps->local_ip, &local_addr.sin_addr) <= 0) {
+        // domain
+        struct hostent *host = gethostbyname(client->ps->local_ip);
+        assert(host != NULL);
+        if (host == NULL) {
+            debug(LOG_ERR, "gethostbyname %s failed", client->ps->local_ip);
+            evbuffer_free(base64_output);
+            return;
+        }
+        memcpy(&local_addr.sin_addr, host->h_addr, host->h_length);
+    } 
+
+    // send buf to local_proxy_bev
+    struct evbuffer *dst = bufferevent_get_output(local_proxy_bev);
+    evbuffer_add_buffer(dst, base64_output);
+    evbuffer_free(base64_output);
+}
+
+void 
+udp_proxy_c2s_cb(struct bufferevent *bev, void *ctx)
+{
+    struct common_conf  *c_conf = get_common_config();
+	struct proxy_client *client = (struct proxy_client *)ctx;
+	assert(client);
+	struct bufferevent *partner = client->ctl_bev;
+	assert(partner);
+	struct evbuffer *src = bufferevent_get_input(bev);
+
+	// encode src to base64
+    struct evbuffer *base64_output = evbuffer_new();
+    evutil_base64_encode(src, base64_output);
+    evbuffer_free(src);
+
+    // convert base64_output to udp_packet and json marshal
+    struct udp_packet *udp_pkt = (struct udp_packet *)malloc(sizeof(struct udp_packet));
+    assert(udp_pkt != NULL);
+    memset(udp_pkt, 0, sizeof(struct udp_packet));
+    udp_pkt->content = evbuffer_pullup(base64_output, -1);
+    udp_pkt->raddr = (struct udp_addr *)malloc(sizeof(struct udp_addr));
+    assert(udp_pkt->raddr != NULL);
+    memset(udp_pkt->raddr, 0, sizeof(struct udp_addr));
+    udp_pkt->raddr->addr = client->ps->local_ip;
+    udp_pkt->raddr->port = client->ps->local_port;
+    char *buf = NULL;
+    new_udp_packet_marshal(udp_pkt, &buf);
+    size_t len = strlen(buf);
+    free(udp_pkt->raddr);
+    free(udp_pkt);
+
+    if (!c_conf->tcp_mux) {
+		struct evbuffer *dst = bufferevent_get_output(partner);
+		evbuffer_add(dst, buf, len);
+        free(buf);
+		return;
+	}
+
+	uint32_t nr = tmux_stream_write(partner, buf, len, &client->stream);
+	if (nr < len) {
+		debug(LOG_DEBUG, "stream_id [%d] len is %d tmux_stream_write %d data, disable read", client->stream.id, len, nr);
+		bufferevent_disable(bev, EV_READ);
+	}
+	free(buf);
+}
+
+void 
+udp_proxy_s2c_cb(struct bufferevent *bev, void *ctx)
+{
+    struct proxy_client *client = (struct proxy_client *)ctx;
+	assert(client);
+}

tcp_redir.c

@@ -0,0 +1,211 @@
+/* vim: set et ts=4 sts=4 sw=4 : */
+/********************************************************************\
+ * This program is free software; you can redistribute it and/or    *
+ * modify it under the terms of the GNU General Public License as   *
+ * published by the Free Software Foundation; either version 2 of   *
+ * the License, or (at your option) any later version.              *
+ *                                                                  *
+ * This program is distributed in the hope that it will be useful,  *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of   *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the    *
+ * GNU General Public License for more details.                     *
+ *                                                                  *
+ * You should have received a copy of the GNU General Public License*
+ * along with this program; if not, contact:                        *
+ *                                                                  *
+ * Free Software Foundation           Voice:  +1-617-542-5942       *
+ * 59 Temple Place - Suite 330        Fax:    +1-617-542-2652       *
+ * Boston, MA  02111-1307,  USA       gnu@gnu.org                   *
+ *                                                                  *
+\********************************************************************/
+
+/** @file tcp_redir.c
+    @brief xfrp tcp redirect service implemented
+    @author Copyright (C) 2023 Dengfeng Liu <liu_df@qq.com>
+*/
+
+#include <pthread.h>
+#include <arpa/inet.h>
+
+#include "common.h"
+#include "debug.h"
+#include "config.h"
+#include "utils.h"
+#include "tcp_redir.h"
+
+
+// define a struct for tcp_redir which include proxy_service and event_base
+struct tcp_redir_service {
+    struct event_base *base;
+    struct proxy_service *ps;
+    struct sockaddr_in server_addr;
+};             
+
+static struct bufferevent *current_bev = NULL; // Global variable to hold the current connection
+
+// define a callback function for read event
+static void read_cb(struct bufferevent *bev, void *arg)
+{
+    struct bufferevent *bev_out = (struct bufferevent *)arg;
+    struct evbuffer *input = bufferevent_get_input(bev);
+    struct evbuffer *output = bufferevent_get_output(bev_out);
+    evbuffer_add_buffer(output, input);
+}
+
+// define a callback function for event event
+static void event_cb(struct bufferevent *bev, short events, void *arg)
+{
+    struct bufferevent *partner = (struct bufferevent *)arg;
+    if (events & BEV_EVENT_CONNECTED) {
+        debug(LOG_INFO, "connected");
+    } else if (events & BEV_EVENT_ERROR) {
+        debug(LOG_ERR, "connection error");
+        bufferevent_free(bev);
+        bufferevent_free(partner);
+        current_bev = NULL;
+    } else if (events & BEV_EVENT_EOF) {
+        debug(LOG_INFO, "connection closed");
+        bufferevent_free(bev);
+        bufferevent_free(partner);
+        current_bev = NULL;
+    }
+}
+
+// define a callback function for accept event
+static void accept_cb(struct evconnlistener *listener, evutil_socket_t fd,
+    struct sockaddr *address, int socklen, void *arg)
+{
+     if (current_bev) {
+        // Already have a connection, reject new connection
+        debug(LOG_INFO, "Rejecting new connection. Only one connection allowed at a time.");
+        evutil_closesocket(fd);
+        return;
+    }
+
+    // the argument is the proxy_service
+    struct tcp_redir_service *trs = (struct tcp_redir_service *)arg;
+    struct event_base *base = trs->base;
+
+    // read the data from the local port
+    struct bufferevent *bev_in = bufferevent_socket_new(base, fd, BEV_OPT_CLOSE_ON_FREE|BEV_OPT_DEFER_CALLBACKS);
+    if (!bev_in) {
+        debug(LOG_ERR, "create bufferevent for local port failed!");
+        evutil_closesocket(fd); 
+        return;
+    }
+
+     // connect to the remote xfrpc service
+    struct bufferevent *bev_out = bufferevent_socket_new(base, -1, BEV_OPT_CLOSE_ON_FREE|BEV_OPT_DEFER_CALLBACKS);
+    if (!bev_out) {
+        debug(LOG_ERR, "create bufferevent for remote xfrps service failed!");
+        bufferevent_free(bev_in);
+        return;
+    }
+
+    // connect to the remote port
+    if (bufferevent_socket_connect(bev_out, (struct sockaddr *)&(trs->server_addr), sizeof(trs->server_addr)) < 0) {
+        debug(LOG_ERR, "connect to remote port failed! %s", strerror(errno));
+        bufferevent_free(bev_in);
+        bufferevent_free(bev_out);
+        return;
+    }
+    debug(LOG_INFO, "connect to remote xfrps service [%s:%d] success!", 
+        get_common_config()->server_addr, trs->ps->remote_port);
+
+    bufferevent_setcb(bev_in, read_cb, NULL, event_cb, (void *)bev_out);
+    bufferevent_setcb(bev_out, read_cb, NULL, event_cb, (void *)bev_in);
+    bufferevent_enable(bev_in, EV_READ|EV_WRITE);
+    bufferevent_enable(bev_out, EV_READ|EV_WRITE);
+
+    current_bev = bev_in;
+
+    debug(LOG_INFO, "connect to remote port success!");
+    return;
+}
+
+// define a thread worker function for tcp_redir
+static void *tcp_redir_worker(void *arg)
+{
+    struct proxy_service *ps = (struct proxy_service *)arg;
+    struct common_conf *c_conf = get_common_config();
+    // the worker is based on libevent and bufferevent
+    // it listens on the local port and forward the data to the remote port
+    // the local port and remote port are defined in the proxy_service
+    // the proxy_service as argument is passed to the worker function
+
+    // create a event_base
+    struct evconnlistener *listener;
+    struct event_base *base = event_base_new();
+    if (!base) {
+        debug(LOG_ERR, "create event base failed!");
+        exit(1);
+    }
+
+    // define listen address and port
+    struct sockaddr_in sin;
+    memset(&sin, 0, sizeof(sin));
+    sin.sin_family = AF_INET;
+    sin.sin_port = htons(ps->local_port);
+    sin.sin_addr.s_addr = htonl(INADDR_ANY);
+    
+    struct tcp_redir_service trs;
+    trs.base = base;
+    trs.ps = ps;
+    trs.server_addr.sin_family = AF_INET;
+    trs.server_addr.sin_port = htons(ps->remote_port);
+    // if c_conf->server_addr is ip address, use inet_addr to convert it
+    // if c_conf->server_addr is domain name, use gethostbyname to convert it
+    if (is_valid_ip_address(c_conf->server_addr))
+        trs.server_addr.sin_addr.s_addr = inet_addr(c_conf->server_addr);
+    else {
+        struct hostent *host = gethostbyname(c_conf->server_addr);
+        if (!host) {
+            debug(LOG_ERR, "gethostbyname failed!");
+            exit(1);
+        }
+        // only support ipv4
+        if (host->h_addrtype != AF_INET) {
+            debug(LOG_ERR, "only support ipv4!");
+            exit(1);
+        }
+        trs.server_addr.sin_addr.s_addr = *(unsigned long *)host->h_addr_list[0];
+    }
+    
+    // create a listener
+    listener = evconnlistener_new_bind(base, accept_cb, (void *)&trs,
+        LEV_OPT_CLOSE_ON_FREE | LEV_OPT_REUSEABLE, -1, (struct sockaddr *)&sin, sizeof(sin));
+    if (!listener) {
+        debug(LOG_ERR, "create listener failed!");
+        exit(1);
+    }
+
+    // start the event loop
+    event_base_dispatch(base);
+
+    // free the listener
+    evconnlistener_free(listener);
+    // free the event base
+    event_base_free(base);
+
+    return NULL;
+}
+
+void start_tcp_redir_service(struct proxy_service *ps)
+{
+    // create a thread 
+    pthread_t tid;
+    if (pthread_create(&tid, NULL, tcp_redir_worker, (void *)ps) != 0) {
+        debug(LOG_ERR, "create tcp_redir worker thread failed!");
+        exit(1);
+    }
+    debug(LOG_INFO, "create tcp_redir worker thread success!");
+
+    // detach the thread
+    if (pthread_detach(tid) != 0) {
+        debug(LOG_ERR, "detach tcp_redir worker thread failed!");
+        exit(1);
+    }
+    debug(LOG_INFO, "detach tcp_redir worker thread success!");
+
+    return;
+}

tcp_redir.h

@@ -0,0 +1,8 @@
+#ifndef _TCP_REDIR_H_
+#define _TCP_REDIR_H_
+
+#include "proxy.h"
+
+void start_tcp_redir_service(struct proxy_service *proxy);
+
+#endif

utils.c

@@ -31,7 +31,7 @@ void s_sleep(unsigned int s, unsigned int u)
 }
 
 // is_valid_ip_address:
-// return 0:ipaddress unlegal
+// return 0:ip address illegal
 int is_valid_ip_address(const char *ip_address) 
 {
     struct sockaddr_in sa;

version.h

@@ -1,7 +1,7 @@
 #ifndef _VERSION_H_
 #define _VERSION_H_
 
-#define VERSION   "2.5.633"
+#define VERSION   "2.9.644"
 #define PROTOCOL_VERESION "0.43.0"
 #define CLIENT_V 1
 

xfrpc.c

@@ -45,11 +45,34 @@
 #include "crypto.h"
 #include "msg.h"
 #include "utils.h"
+#include "tcp_redir.h"
+#include "config.h"
+
+#include "plugins/telnetd.h"
+
+static void start_xfrpc_local_service()
+{
+	// iterate all proxy service to find mstsc service
+	// if found, start tcp_redir for it
+	struct proxy_service *ps, *ps_tmp;
+	struct proxy_service *all_ps = get_all_proxy_services();
+	HASH_ITER(hh, all_ps, ps, ps_tmp) {
+		if (ps->proxy_type && strcmp(ps->proxy_type, "mstsc") == 0) {
+			// start tcp_redir for it
+			start_tcp_redir_service(ps);
+		}
+		if (ps->plugin && strcmp(ps->plugin, "telnetd") == 0) {
+			simple_telnetd_start(ps->local_port);
+		}
+	}
+
+	
+}
 
 void xfrpc_loop()
 {
+	start_xfrpc_local_service();
 	init_main_control();
 	run_control();
-	
 	close_main_control();
 }