SOCKS5 support (#452)

* Add termix.rb Cask file

* Update Termix to version 1.9.0 with new checksum

* Update README to remove 'coming soon' notes

* SOCKS5 support

Adding single and chain socks5 proxy support

* fix: cleanup files

---------

Co-authored-by: Luke Gustafson <88517757+LukeGus@users.noreply.github.com>
Co-authored-by: LukeGus <bugattiguy527@gmail.com>

src/backend/utils/socks5-helper.ts

@@ -0,0 +1,160 @@
+import { SocksClient } from "socks";
+import type { SocksClientOptions } from "socks";
+import net from "net";
+import { sshLogger } from "./logger.js";
+import type { ProxyNode } from "../../types/index.js";
+
+export interface SOCKS5Config {
+  useSocks5?: boolean;
+  socks5Host?: string;
+  socks5Port?: number;
+  socks5Username?: string;
+  socks5Password?: string;
+  socks5ProxyChain?: ProxyNode[];
+}
+
+/**
+ * Creates a SOCKS5 connection through a single proxy or a chain of proxies
+ * @param targetHost - Target SSH server hostname/IP
+ * @param targetPort - Target SSH server port
+ * @param socks5Config - SOCKS5 proxy configuration
+ * @returns Promise with connected socket or null if SOCKS5 is not enabled
+ */
+export async function createSocks5Connection(
+  targetHost: string,
+  targetPort: number,
+  socks5Config: SOCKS5Config,
+): Promise<net.Socket | null> {
+  // If SOCKS5 is not enabled, return null
+  if (!socks5Config.useSocks5) {
+    return null;
+  }
+
+  // If proxy chain is provided, use chain connection
+  if (socks5Config.socks5ProxyChain && socks5Config.socks5ProxyChain.length > 0) {
+    return createProxyChainConnection(targetHost, targetPort, socks5Config.socks5ProxyChain);
+  }
+
+  // If single proxy is configured, use single proxy connection
+  if (socks5Config.socks5Host) {
+    return createSingleProxyConnection(targetHost, targetPort, socks5Config);
+  }
+
+  // No proxy configured
+  return null;
+}
+
+/**
+ * Creates a connection through a single SOCKS proxy
+ */
+async function createSingleProxyConnection(
+  targetHost: string,
+  targetPort: number,
+  socks5Config: SOCKS5Config,
+): Promise<net.Socket> {
+  const socksOptions: SocksClientOptions = {
+    proxy: {
+      host: socks5Config.socks5Host!,
+      port: socks5Config.socks5Port || 1080,
+      type: 5,
+      userId: socks5Config.socks5Username,
+      password: socks5Config.socks5Password,
+    },
+    command: "connect",
+    destination: {
+      host: targetHost,
+      port: targetPort,
+    },
+  };
+
+  sshLogger.info("Creating SOCKS5 connection", {
+    operation: "socks5_connect",
+    proxyHost: socks5Config.socks5Host,
+    proxyPort: socks5Config.socks5Port || 1080,
+    targetHost,
+    targetPort,
+    hasAuth: !!(socks5Config.socks5Username && socks5Config.socks5Password),
+  });
+
+  try {
+    const info = await SocksClient.createConnection(socksOptions);
+
+    sshLogger.info("SOCKS5 connection established", {
+      operation: "socks5_connected",
+      targetHost,
+      targetPort,
+    });
+
+    return info.socket;
+  } catch (error) {
+    sshLogger.error("SOCKS5 connection failed", error, {
+      operation: "socks5_connect_failed",
+      proxyHost: socks5Config.socks5Host,
+      proxyPort: socks5Config.socks5Port || 1080,
+      targetHost,
+      targetPort,
+      errorMessage: error instanceof Error ? error.message : "Unknown error",
+    });
+    throw error;
+  }
+}
+
+/**
+ * Creates a connection through a chain of SOCKS proxies
+ * Each proxy in the chain connects through the previous one
+ */
+async function createProxyChainConnection(
+  targetHost: string,
+  targetPort: number,
+  proxyChain: ProxyNode[],
+): Promise<net.Socket> {
+  if (proxyChain.length === 0) {
+    throw new Error("Proxy chain is empty");
+  }
+
+  const chainPath = proxyChain.map((p) => `${p.host}:${p.port}`).join(" → ");
+  sshLogger.info(`Creating SOCKS proxy chain: ${chainPath} → ${targetHost}:${targetPort}`, {
+    operation: "socks5_chain_connect",
+    chainLength: proxyChain.length,
+    targetHost,
+    targetPort,
+    proxies: proxyChain.map((p) => `${p.host}:${p.port}`),
+  });
+
+  try {
+    const info = await SocksClient.createConnectionChain({
+      proxies: proxyChain.map((p) => ({
+        host: p.host,
+        port: p.port,
+        type: p.type,
+        userId: p.username,
+        password: p.password,
+        timeout: 10000, // 10-second timeout for each hop
+      })),
+      command: "connect",
+      destination: {
+        host: targetHost,
+        port: targetPort,
+      },
+    });
+
+    sshLogger.info(`✓ Proxy chain established: ${chainPath} → ${targetHost}:${targetPort}`, {
+      operation: "socks5_chain_connected",
+      chainLength: proxyChain.length,
+      targetHost,
+      targetPort,
+      fullPath: `${chainPath} → ${targetHost}:${targetPort}`,
+    });
+
+    return info.socket;
+  } catch (error) {
+    sshLogger.error("SOCKS proxy chain connection failed", error, {
+      operation: "socks5_chain_connect_failed",
+      chainLength: proxyChain.length,
+      targetHost,
+      targetPort,
+      errorMessage: error instanceof Error ? error.message : "Unknown error",
+    });
+    throw error;
+  }
+}