服务端支持配置多局域网组网

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.18.4)
 
-project(candy LANGUAGES C CXX VERSION 5.9.3)
+project(candy LANGUAGES C CXX VERSION 5.9.4)
 
 option(CANDY_NOEXE  "Don't build executable")
 option(CANDY_DEVEL  "Build development library")

README.md

@@ -164,6 +164,14 @@ dhcp = "10.0.0.0/24"
 password = "123456"
 ```
 
+配置[多局域网组网](docs/muti-lan-interconn.md)
+
+```bash
+# 进入设备网络 10.0.0.1/32 且目的网络为 192.168.2.0/24 的 IP 报文通过 10.0.0.2 转发,
+# 通过分号分割的多条规则,配置中禁止出现空白符.
+sdwan = "10.0.0.1/32,192.168.2.0/24,10.0.0.2;10.0.0.2/32,192.168.1.0/24,10.0.0.1";
+```
+
 #### 客户端
 
 与上述服务端匹配的客户端配置
@@ -186,7 +194,7 @@ stun = "stun://stun.canets.org"
 port = 0
 ```
 
-关于路由的配置
+配置客户端中继
 
 ```bash
 # 路由功能在对等连接的基础上工作,对等连接是被动启动,
@@ -201,7 +209,7 @@ discovery = 300
 route = 5
 ```
 
-关于局域网内建立对等的配置
+配置局域网内对等链接
 
 ```bash
 # 用于建立对等连接的本机局域网 IP 地址,不配置此项时将尝试自动获取.

candy.cfg

@@ -25,6 +25,12 @@ websocket = "wss://canets.org/demo";
 # configure a static address through tun.
 #dhcp = "172.16.0.0/16";
 
+# [Optional] software-defined wide area network
+# IP packets entering 172.16.0.1/32 with the destination address 192.168.2.0/24
+# will be forwarded to 172.16.0.2. Multiple rules are separated by semicolons.
+# Extraneous whitespace characters are prohibited.
+#sdwan = "172.16.0.1/32,192.168.2.0/24,172.16.0.2;172.16.0.2/32,192.168.1.0/24,172.16.0.1";
+
 ################################# Client Only #################################
 # [Optional] Network interface name
 # Used to differentiate networks when running multiple clients.

docs/muti-lan-interconn.md

@@ -8,7 +8,7 @@
 
 此处假设你已经:
 
-- 成功部署 Web 版本[服务端](https://hub.docker.com/r/lanthora/cucurbita)
+- 成功部署服务端
 - 在网关 (Gateway) 上部署 Candy 并分配了虚拟地址
 
 以 LAN A 为例解释表格含义.

src/core/server.cc

@@ -7,6 +7,7 @@
 #include <Poco/URI.h>
 #include <spdlog/fmt/bin_to_hex.h>
 #include <spdlog/spdlog.h>
+#include <sstream>
 
 namespace Candy {
 
@@ -47,6 +48,34 @@ int Server::setDynamicAddressRange(const std::string &cidr) {
     return 0;
 }
 
+int Server::setSdwan(const std::string &sdwan) {
+    if (sdwan.empty()) {
+        return 0;
+    }
+    std::string route;
+    std::stringstream stream(sdwan);
+    while (std::getline(stream, route, ';')) {
+        std::string addr;
+        SysRoute rt;
+        std::stringstream ss(route);
+        if (!std::getline(ss, addr, ',') || rt.dev.cidrUpdate(addr) || rt.dev.getIp() != rt.dev.getNet()) {
+            spdlog::critical("invalid route device: {}", route);
+            return -1;
+        }
+        if (!std::getline(ss, addr, ',') || rt.dst.cidrUpdate(addr) || rt.dst.getIp() != rt.dst.getNet()) {
+            spdlog::critical("invalid route dest: {}", route);
+            return -1;
+        }
+        if (!std::getline(ss, addr, ',') || rt.next.ipStrUpdate(addr)) {
+            spdlog::critical("invalid route nexthop: {}", route);
+            return -1;
+        }
+        spdlog::info("route: dev={} dst={} next={}", rt.dev.getCidr(), rt.dst.getCidr(), rt.next.getIpStr());
+        this->routes.push_back(rt);
+    }
+    return 0;
+}
+
 int Server::run() {
     this->running = true;
     if (startWsThread()) {
@@ -180,6 +209,7 @@ void Server::handleAuthMessage(WebSocketMessage &message) {
 
     this->ipWsMap[address.getIp()] = message.conn;
     this->wsIpMap[message.conn] = address.getIp();
+    updateClientRoute(message, address.getIp());
 }
 
 void Server::handleForwardMessage(WebSocketMessage &message) {
@@ -468,4 +498,26 @@ void Server::handleCloseMessage(WebSocketMessage &message) {
     this->wsMacMap.erase(message.conn);
 }
 
+void Server::updateClientRoute(WebSocketMessage &message, uint32_t client) {
+    message.buffer.resize(sizeof(SysRouteMessage));
+    SysRouteMessage *header = (SysRouteMessage *)message.buffer.data();
+    memset(header, 0, sizeof(SysRouteMessage));
+    header->type = MessageType::ROUTE;
+
+    for (auto rt : this->routes) {
+        if ((rt.dev.getMask() & client) == rt.dev.getIp()) {
+            SysRouteItem item;
+            item.dest = Address::hostToNet(rt.dst.getNet());
+            item.mask = Address::hostToNet(rt.dst.getMask());
+            item.nexthop = Address::hostToNet(rt.next.getIp());
+            message.buffer.append((char *)(&item), sizeof(item));
+            header->size += 1;
+        }
+    }
+
+    if (header->size > 0) {
+        this->ws.write(message);
+    }
+}
+
 } // namespace Candy

src/core/server.h

@@ -4,17 +4,25 @@
 
 #include "utility/address.h"
 #include "websocket/server.h"
+#include <list>
 #include <map>
 #include <string>
 #include <thread>
 
 namespace Candy {
 
+struct SysRoute {
+    Address dev;
+    Address dst;
+    Address next;
+};
+
 class Server {
 public:
     int setWebSocketServer(const std::string &uri);
     int setPassword(const std::string &password);
     int setDynamicAddressRange(const std::string &cidr);
+    int setSdwan(const std::string &sdwan);
 
     int run();
     int shutdown();
@@ -32,6 +40,8 @@ class Server {
     void handleGeneralMessage(WebSocketMessage &message);
     void handleCloseMessage(WebSocketMessage &message);
 
+    void updateClientRoute(WebSocketMessage &message, uint32_t client);
+
     bool running = false;
     uint16_t port;
     std::string host;
@@ -45,6 +55,7 @@ class Server {
     std::map<uint32_t, WebSocketConn> ipWsMap;
     std::map<WebSocketConn, uint32_t> wsIpMap;
     std::map<WebSocketConn, std::string> wsMacMap;
+    std::list<SysRoute> routes;
 };
 
 } // namespace Candy

src/main/main.cc

@@ -31,6 +31,7 @@ struct arguments {
 
     // 服务端配置
     std::string dhcp;
+    std::string sdwan;
 
     // 客户端配置
     std::string name;
@@ -82,6 +83,7 @@ void parseConfig(std::string cfgFile, arguments &args) {
             {"debug", [&](const std::string &value) { args.debug = (value == "true"); }},
             {"restart", [&](const std::string &value) { args.restart = std::stoi(value); }},
             {"dhcp", [&](const std::string &value) { args.dhcp = value; }},
+            {"sdwan", [&](const std::string &value) { args.sdwan = value; }},
             {"tun", [&](const std::string &value) { args.tun = value; }},
             {"stun", [&](const std::string &value) { args.stun = value; }},
             {"name", [&](const std::string &value) { args.name = value; }},
@@ -256,6 +258,7 @@ int serve(const arguments &args) {
         server.setPassword(args.password);
         server.setWebSocketServer(args.websocket);
         server.setDynamicAddressRange(args.dhcp);
+        server.setSdwan(args.sdwan);
         server.run();
     }
 
@@ -299,6 +302,7 @@ int parseConfig(int argc, char *argv[], arguments &args) {
     program.add_argument("-p", "--password").help("authorization password").metavar("TEXT");
     program.add_argument("--restart").help("restart interval").scan<'i', int>().metavar("SECONDS");
     program.add_argument("-d", "--dhcp").help("dhcp address range").metavar("CIDR");
+    program.add_argument("--sdwan").help("software-defined wide area network").metavar("ROUTES");
     program.add_argument("-n", "--name").help("network interface name").metavar("TEXT");
     program.add_argument("-t", "--tun").help("static address").metavar("CIDR");
     program.add_argument("-s", "--stun").help("stun address").metavar("URI");
@@ -323,6 +327,7 @@ int parseConfig(int argc, char *argv[], arguments &args) {
         args.noTimestamp = program.is_used("--no-timestamp") ? program.get<bool>("--no-timestamp") : args.noTimestamp;
         args.debug = program.is_used("--debug") ? program.get<bool>("--debug") : args.debug;
         args.dhcp = program.is_used("--dhcp") ? program.get<std::string>("--dhcp") : args.dhcp;
+        args.sdwan = program.is_used("--sdwan") ? program.get<std::string>("--sdwan") : args.sdwan;
         args.name = program.is_used("--name") ? program.get<std::string>("--name") : args.name;
         args.tun = program.is_used("--tun") ? program.get<std::string>("--tun") : args.tun;
         args.stun = program.is_used("--stun") ? program.get<std::string>("--stun") : args.stun;