Support for ipv6 addresses (with or without port specified) (#536)

* Support for ipv6 addresses (with or without port specified)

Currently et does not support passing an ipv6 address as the host
positional argument is assumed to be an ipv4 address or hostname with a
single colon with the port after it and the rest is ignored, eg:

```
$ et 2620:10d:c083:1418:14ac:6bbc:4737:56ee                                                                                                                                     15:19:52  10.07.22  100% █
Could not reach the ET server: 2620:10
```

This change will support ipv4 address or hostname with port specified or
ipv6 address with or without port specified.  Currently, if a port is
specified in the positional arg, it overwrites what was specified
(explicitly or by default) with the -p,--port option. I think this is
backwards and may offer a PR to invert this logic.

* etterminal option/description cleanup plus other housecleaning.

No-op changes:
* TerminalMain: change binary name/description
* TerminalMain: get rid of Daemon log file (does nothing now)
* SubprocessToString: reorganize forking logic and remove irrelevant
  comments and cleanup trailing whitespace
* PsuedoUserTerminal: breaks in forking switch statement

* Rename et --prefix option to --terminal-path.

The prefix option to the terminal client is misleading as it isn't a
prefix (or search path) and is treated as an absolute path to the
etterminal executable.  This renames it as such and removes the
superfluous positional arg in the command string building for the ssh
command (i.e. /usr/local/bin/etterminal etterminal -v 0)

.circleci/config.yml

@@ -13,7 +13,8 @@ jobs:
  - checkout
  - run:
  name: Set up ssh & known_hosts
- command: sudo /etc/init.d/ssh start; rm -f ~/.ssh/id_rsa*; ssh-keygen -q -N "" -f ~/.ssh/id_rsa; sudo rm -f ~/.ssh/authorized_keys; cp ~/.ssh/id_rsa.pub ~/.ssh/authorized_keys; rm -f ~/.ssh/known_hosts; ssh -o "StrictHostKeyChecking no" localhost ls
+ command: sudo sed -i -e 's/#ListenAddress/ListenAddress/' /etc/ssh/sshd_config; sudo sed -i -e 's/AddressFamily inet/AddressFamily any/' /etc/ssh/sshd_config; sudo /etc/init.d/ssh restart; rm -f ~/.ssh/id_rsa*; ssh-keygen -q -N "" -f ~/.ssh/id_rsa; sudo rm -f ~/.ssh/authorized_keys; cp ~/.ssh/id_rsa.pub ~/.ssh/authorized_keys; rm -f ~/.ssh/known_hosts; ssh -o "StrictHostKeyChecking no" localhost ls; ssh -o "StrictHostKeyChecking no" 0:0:0:0:0:0:0:1 ls
+
  - run:
  name: Init submodules
  command: if [ $CIRCLE_BRANCH != "release" ]; then git submodule update --init --recursive; fi
@@ -31,6 +32,12 @@ jobs:
  - run:
  name: Connect new -> old
  command: sudo ../root_version/build/etserver --daemon; sudo cp ../root_version/build/etterminal /usr/bin/etterminal; sleep 1; build/et -c "ls" localhost --logtostdout --verbose=9
+ - run:
+ name: Connect new -> old (ipv6)
+ command: build/et -c "ls" 0:0:0:0:0:0:0:1 --logtostdout --verbose=9
+ - run:
+ name: Connect new -> old (ipv6 with port in host)
+ command: build/et -c "ls" 0:0:0:0:0:0:0:1:2022 --logtostdout --verbose=9
  - run:
  name: Kill server
  command: sudo pkill etserver

src/base/SubprocessToString.cpp

@@ -2,7 +2,7 @@
 
 namespace et {
 #ifdef WIN32
-#define BUFSIZE 4096 
+#define BUFSIZE 4096
 
  void ErrorExit(PTSTR);
 
@@ -14,13 +14,13 @@ namespace et {
  HANDLE g_hChildStd_OUT_Wr = NULL;
 
 
- // Set the bInheritHandle flag so pipe handles are inherited. 
+ // Set the bInheritHandle flag so pipe handles are inherited.
 
  saAttr.nLength = sizeof(SECURITY_ATTRIBUTES);
  saAttr.bInheritHandle = TRUE;
  saAttr.lpSecurityDescriptor = NULL;
 
- // Create a pipe for the child process's STDOUT. 
+ // Create a pipe for the child process's STDOUT.
 
  if (!CreatePipe(&g_hChildStd_OUT_Rd, &g_hChildStd_OUT_Wr, &saAttr, 0))
  ErrorExit(TEXT("StdoutRd CreatePipe"));
@@ -30,12 +30,12 @@ namespace et {
  if (!SetHandleInformation(g_hChildStd_OUT_Rd, HANDLE_FLAG_INHERIT, 0))
  ErrorExit(TEXT("Stdout SetHandleInformation"));
 
- // Create a pipe for the child process's STDIN. 
+ // Create a pipe for the child process's STDIN.
 
  if (!CreatePipe(&g_hChildStd_IN_Rd, &g_hChildStd_IN_Wr, &saAttr, 0))
  ErrorExit(TEXT("Stdin CreatePipe"));
 
- // Ensure the write handle to the pipe for STDIN is not inherited. 
+ // Ensure the write handle to the pipe for STDIN is not inherited.
 
  if (!SetHandleInformation(g_hChildStd_IN_Wr, HANDLE_FLAG_INHERIT, 0))
  ErrorExit(TEXT("Stdin SetHandleInformation"));
@@ -50,11 +50,11 @@ namespace et {
  STARTUPINFO siStartInfo;
  BOOL bSuccess = FALSE;
 
- // Set up members of the PROCESS_INFORMATION structure. 
+ // Set up members of the PROCESS_INFORMATION structure.
 
  ZeroMemory(&piProcInfo, sizeof(PROCESS_INFORMATION));
 
- // Set up members of the STARTUPINFO structure. 
+ // Set up members of the STARTUPINFO structure.
  // This structure specifies the STDIN and STDOUT handles for redirection.
 
  ZeroMemory(&siStartInfo, sizeof(STARTUPINFO));
@@ -64,30 +64,30 @@ namespace et {
  siStartInfo.hStdInput = g_hChildStd_IN_Rd;
  siStartInfo.dwFlags |= STARTF_USESTDHANDLES;
 
- // Create the child process. 
+ // Create the child process.
 
  std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> converter;
  std::wstring wide = converter.from_bytes(localCommand);
 
  bSuccess = CreateProcess(NULL,
- &(wide[0]), // command line 
- NULL, // process security attributes 
- NULL, // primary thread security attributes 
- TRUE, // handles are inherited 
- 0, // creation flags 
- NULL, // use parent's environment 
- NULL, // use parent's current directory 
- &siStartInfo, // STARTUPINFO pointer 
- &piProcInfo); // receives PROCESS_INFORMATION 
-
- // If an error occurs, exit the application. 
+ &(wide[0]), // command line
+ NULL, // process security attributes
+ NULL, // primary thread security attributes
+ TRUE, // handles are inherited
+ 0, // creation flags
+ NULL, // use parent's environment
+ NULL, // use parent's current directory
+ &siStartInfo, // STARTUPINFO pointer
+ &piProcInfo); // receives PROCESS_INFORMATION
+
+ // If an error occurs, exit the application.
  if (!bSuccess)
  ErrorExit(TEXT("CreateProcess"));
  else
  {
  // Close handles to the child process and its primary thread.
  // Some applications might keep these handles to monitor the status
- // of the child process, for example. 
+ // of the child process, for example.
 
  CloseHandle(piProcInfo.hProcess);
  CloseHandle(piProcInfo.hThread);
@@ -99,10 +99,10 @@ namespace et {
  CloseHandle(g_hChildStd_IN_Rd);
  }
 
- // Read from pipe that is the standard output for child process. 
+ // Read from pipe that is the standard output for child process.
  // Read output from the child process's pipe for STDOUT
- // and write to the parent process's pipe for STDOUT. 
- // Stop when there is no more data. 
+ // and write to the parent process's pipe for STDOUT.
+ // Stop when there is no more data.
  DWORD dwRead, dwWritten;
  CHAR chBuf[BUFSIZE];
  bSuccess = FALSE;
@@ -117,20 +117,20 @@ namespace et {
  childOutput += string((const char*)chBuf, (size_t)dwRead);
  }
 
- // The remaining open handles are cleaned up when this process terminates. 
- // To avoid resource leaks in a larger application, close handles explicitly. 
+ // The remaining open handles are cleaned up when this process terminates.
+ // To avoid resource leaks in a larger application, close handles explicitly.
 
  return childOutput;
  }
 
-#include <windows.h> 
+#include <windows.h>
 #include <tchar.h>
-#include <stdio.h> 
+#include <stdio.h>
 #include <strsafe.h>
 
  void ErrorExit(PTSTR lpszFunction)
 
- // Format a readable error message, display a message box, 
+ // Format a readable error message, display a message box,
  // and exit from the application.
  {
  LPVOID lpMsgBuf;
@@ -169,9 +169,9 @@ namespace et {
  }
 
  pid_t pid = fork();
- if (!pid) {
- // start etserver daemon on dst.
- dup2(link_client[1], 1);
+ if (pid == 0) {
+ // child process
+ dup2(link_client[1], STDOUT_FILENO);
  close(link_client[0]);
  close(link_client[1]);
 
@@ -181,21 +181,17 @@ namespace et {
  argsArray[a + 1] = strdup(args[a].c_str());
  }
  argsArray[args.size() + 1] = NULL;
- // run the command in interactive mode
  execvp(command.c_str(), argsArray);
 
- LOG(INFO) << "execl error";
+ LOG(INFO) << "execvp error";
  for (int a = 0; a <= args.size(); a++) {
  free(argsArray[a]);
  }
  delete[] argsArray;
  exit(1);
  }
- else if (pid < 0) {
- LOG(INFO) << "Failed to fork";
- exit(1);
- }
- else {
+ else if (pid > 0) {
+ // parent process
  close(link_client[1]);
  wait(NULL);
  string sshBuffer;
@@ -208,7 +204,11 @@ namespace et {
  }
  return sshBuffer;
  }
+ else {
+ LOG(INFO) << "Failed to fork";
+ exit(1);
+ }
  }
 #endif
 
-}
+}

src/terminal/PsuedoUserTerminal.hpp

@@ -31,14 +31,15 @@ class PsuedoUserTerminal : public UserTerminal {
  switch (pid) {
  case -1:
  FATAL_FAIL(pid);
+ break;
  case 0: {
  close(routerFd);
  runTerminal();
+ // only get here if execl fails so a break is not needed since we exit
  exit(0);
  }
  default: {
  // parent
- break;
  }
  }
 

src/terminal/SshSetupHandler.cpp

@@ -3,21 +3,25 @@
 #include "SubprocessToString.hpp"
 
 namespace et {
+const string SshSetupHandler::ETTERMINAL_BIN = "etterminal";
+
 string genCommand(const string& passkey, const string& id,
  const string& clientTerm, const string& user, bool kill,
- const string& command_prefix, const string& options) {
- string SSH_SCRIPT_PREFIX;
+ const string& etterminal_path, const string& options) {
+ string ssh_script_prefix;
+ string etterminal_bin =
+ etterminal_path.empty() ? SshSetupHandler::ETTERMINAL_BIN : etterminal_path;
 
- string COMMAND = "echo '" + id + "/" + passkey + "_" + clientTerm + "\n' | " +
- command_prefix + " etterminal " + options;
+ string command = "echo '" + id + "/" + passkey + "_" + clientTerm + "' | " +
+ etterminal_bin + " " + options;
 
  // Kill old ET sessions of the user
  if (kill) {
- SSH_SCRIPT_PREFIX =
- "pkill etterminal -u " + user + "; sleep 0.5; " + SSH_SCRIPT_PREFIX;
+ ssh_script_prefix =
+ "pkill etterminal -u " + user + "; sleep 0.5; " + ssh_script_prefix;
  }
 
- return SSH_SCRIPT_PREFIX + COMMAND;
+ return ssh_script_prefix + command;
 }
 
 string SshSetupHandler::SetupSsh(const string& user, const string& host,

src/terminal/SshSetupHandler.hpp

@@ -9,9 +9,10 @@ class SshSetupHandler {
  static string SetupSsh(const string &user, const string &host,
  const string &host_alias, int port,
  const string &jumphost, int jport, bool kill,
- int vlevel, const string &cmd_prefix,
+ int vlevel, const string &etterminal_path,
  const string &serverFifo,
  const std::vector<std::string>& ssh_options);
+ static const string ETTERMINAL_BIN;
 };
 } // namespace et
 #endif // __ET_SSH_SETUP_HANDLER__

src/terminal/TerminalClientMain.cpp

@@ -51,7 +51,8 @@ int main(int argc, char** argv) {
  cxxopts::value<int>()->default_value("2022")) //
  ("c,command", "Run command on connect",
  cxxopts::value<std::string>()) //
- ("prefix", "Add prefix when launching etterminal on server side",
+ ("terminal-path", "Path to etterminal on server side. "
+ "Use if etterminal is not on the system path.",
  cxxopts::value<std::string>()) //
  ("t,tunnel",
  "Tunnel: Array of source:destination ports or "
@@ -69,8 +70,8 @@ int main(int argc, char** argv) {
  ("x,kill-other-sessions",
  "kill all old sessions belonging to the user") //
  ("macserver",
- "Set when connecting to an OS/X server. Sets "
- "--prefix=/usr/local/bin/etterminal") //
+ "Set when connecting to an macOS server. Sets "
+ "--terminal-path=/usr/local/bin/etterminal") //
  ("v,verbose", "Enable verbose logging",
  cxxopts::value<int>()->default_value("0")) //
  ("k,keepalive", "Client keepalive duration in seconds",
@@ -144,18 +145,29 @@ int main(int argc, char** argv) {
  CLOG(INFO, "stdout") << options.help({}) << endl;
  exit(0);
  }
- string arg = result["host"].as<std::string>();
- if (arg.find('@') != string::npos) {
- int i = arg.find('@');
- username = arg.substr(0, i);
- arg = arg.substr(i + 1);
+ string host_arg = result["host"].as<std::string>();
+ if (host_arg.find('@') != string::npos) {
+ int i = host_arg.find('@');
+ username = host_arg.substr(0, i);
+ host_arg = host_arg.substr(i + 1);
  }
- if (arg.find(':') != string::npos) {
- int i = arg.find(':');
- destinationPort = stoi(arg.substr(i + 1));
- arg = arg.substr(0, i);
+
+ if (host_arg.find(':') != string::npos) {
+ int colon_count = std::count(host_arg.begin(), host_arg.end(), ':');
+ if (colon_count == 1 || colon_count == 8) {
+ // ipv4 or hostname or ipv6 with port specified
+ int port_colon_pos = host_arg.rfind(':');
+ destinationPort = stoi(host_arg.substr(port_colon_pos + 1));
+ host_arg = host_arg.substr(0, port_colon_pos);
+ } else if (colon_count == 7) {
+ // ipv6 without port specified
+ } else {
+ CLOG(INFO, "stdout") << "Invalid host positional arg: "
+ << result["host"].as<std::string>() << endl;
+ exit(1);
+ }
  }
- destinationHost = arg;
+ destinationHost = host_arg;
 
  string jumphost =
  result.count("jumphost") ? result["jumphost"].as<string>() : "";
@@ -254,17 +266,17 @@ int main(int argc, char** argv) {
  if (result.count("ssh-option")) {
  ssh_options = result["ssh-option"].as<std::vector<string>>();
  }
- string prefix = "";
+ string etterminal_path = "";
  if (result.count("macserver") > 0) {
- prefix = "/usr/local/bin/etterminal";
+ etterminal_path = "/usr/local/bin/etterminal";
  }
- if (result.count("prefix")) {
- prefix = result["prefix"].as<string>();
+ if (result.count("etterminal_path")) {
+ etterminal_path = result["terminal-path"].as<string>();
  }
  string idpasskeypair = SshSetupHandler::SetupSsh(
  username, destinationHost, host_alias, destinationPort, jumphost, jport,
- result.count("x") > 0, result["verbose"].as<int>(), prefix, serverFifo,
- ssh_options);
+ result.count("x") > 0, result["verbose"].as<int>(), etterminal_path,
+ serverFifo, ssh_options);
 
  string id = "", passkey = "";
  // Trim whitespace