guacamole-spice-protocol/protocols/ssh/src/ssh_client.c

273 lines
8.0 KiB
C

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is libguac-client-ssh.
*
* The Initial Developer of the Original Code is
* Michael Jumper.
* Portions created by the Initial Developer are Copyright (C) 2011
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* James Muehlner <dagger10k@users.sourceforge.net>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include <stdio.h>
#include <string.h>
#include <pthread.h>
#include <guacamole/client.h>
#include <guacamole/protocol.h>
#include <guacamole/socket.h>
#include "client.h"
/**
* Similar to write, but automatically retries the write operation until
* an error occurs.
*/
static int __write_all(int fd, const char* buffer, int size) {
int remaining = size;
while (remaining > 0) {
/* Attempt to write data */
int ret_val = write(fd, buffer, remaining);
if (ret_val <= 0)
return -1;
/* If successful, contine with what data remains (if any) */
remaining -= ret_val;
buffer += ret_val;
}
return size;
}
/**
* Reads a single line from STDIN.
*/
static char* prompt(guac_client* client, const char* title, char* str, int size, bool echo) {
ssh_guac_client_data* client_data = (ssh_guac_client_data*) client->data;
int pos;
char in_byte;
/* Get STDIN and STDOUT */
int stdin_fd = client_data->stdin_pipe_fd[0];
int stdout_fd = client_data->stdout_pipe_fd[1];
/* Print title */
__write_all(stdout_fd, title, strlen(title));
/* Make room for null terminator */
size--;
/* Read bytes until newline */
pos = 0;
while (pos < size && read(stdin_fd, &in_byte, 1) == 1) {
/* Backspace */
if (in_byte == 0x08) {
if (pos > 0) {
__write_all(stdout_fd, "\b \b", 3);
pos--;
}
}
/* Newline (end of input */
else if (in_byte == 0x0A) {
__write_all(stdout_fd, "\r\n", 2);
break;
}
else {
/* Store character, update buffers */
str[pos++] = in_byte;
/* Print character if echoing */
if (echo)
__write_all(stdout_fd, &in_byte, 1);
else
__write_all(stdout_fd, "*", 1);
}
}
str[pos] = 0;
return str;
}
void* ssh_input_thread(void* data) {
guac_client* client = (guac_client*) data;
ssh_guac_client_data* client_data = (ssh_guac_client_data*) client->data;
char buffer[8192];
int bytes_read;
int stdin_fd = client_data->stdin_pipe_fd[0];
/* Write all data read */
while ((bytes_read = read(stdin_fd, buffer, sizeof(buffer))) > 0)
channel_write(client_data->term_channel, buffer, bytes_read);
return NULL;
}
void* ssh_client_thread(void* data) {
guac_client* client = (guac_client*) data;
ssh_guac_client_data* client_data = (ssh_guac_client_data*) client->data;
guac_socket* socket = client->socket;
char buffer[8192];
int bytes_read = -1234;
int stdout_fd = client_data->stdout_pipe_fd[1];
pthread_t input_thread;
/* Get username */
if (client_data->username[0] == 0 &&
prompt(client, "Login as: ", client_data->username, sizeof(client_data->username), true) == NULL)
return NULL;
/* Get password */
if (client_data->password[0] == 0 &&
prompt(client, "Password: ", client_data->password, sizeof(client_data->password), false) == NULL)
return NULL;
/* Open SSH session */
client_data->session = ssh_new();
if (client_data->session == NULL) {
guac_protocol_send_error(socket, "Unable to create SSH session.");
guac_socket_flush(socket);
return NULL;
}
/* Set session options */
ssh_options_set(client_data->session, SSH_OPTIONS_HOST, client_data->hostname);
ssh_options_set(client_data->session, SSH_OPTIONS_USER, client_data->username);
/* Connect */
if (ssh_connect(client_data->session) != SSH_OK) {
guac_protocol_send_error(socket, "Unable to connect via SSH.");
guac_socket_flush(socket);
return NULL;
}
/* Authenticate */
if (ssh_userauth_password(client_data->session, NULL, client_data->password) != SSH_AUTH_SUCCESS) {
guac_protocol_send_error(socket, "SSH auth failed.");
guac_socket_flush(socket);
return NULL;
}
/* Open channel for terminal */
client_data->term_channel = channel_new(client_data->session);
if (client_data->term_channel == NULL) {
guac_protocol_send_error(socket, "Unable to open channel.");
guac_socket_flush(socket);
return NULL;
}
/* Open session for channel */
if (channel_open_session(client_data->term_channel) != SSH_OK) {
guac_protocol_send_error(socket, "Unable to open channel session.");
guac_socket_flush(socket);
return NULL;
}
/* Request PTY */
if (channel_request_pty(client_data->term_channel) != SSH_OK) {
guac_protocol_send_error(socket, "Unable to allocate PTY for channel.");
guac_socket_flush(socket);
return NULL;
}
/* Request PTY size */
if (channel_change_pty_size(client_data->term_channel,
client_data->term->term_width, client_data->term->term_height) != SSH_OK) {
guac_protocol_send_error(socket, "Unable to change PTY size.");
guac_socket_flush(socket);
return NULL;
}
/* Request shell */
if (channel_request_shell(client_data->term_channel) != SSH_OK) {
guac_protocol_send_error(socket, "Unable to associate shell with PTY.");
guac_socket_flush(socket);
return NULL;
}
/* Logged in */
guac_client_log_info(client, "SSH connection successful.");
/* Start input thread */
if (pthread_create(&(input_thread), NULL, ssh_input_thread, (void*) client)) {
guac_client_log_error(client, "Unable to start SSH input thread");
return NULL;
}
/* While data available, write to terminal */
while (channel_is_open(client_data->term_channel)
&& !channel_is_eof(client_data->term_channel)) {
/* Repeat read if necessary */
if ((bytes_read = channel_read(client_data->term_channel, buffer, sizeof(buffer), 0)) == SSH_AGAIN)
continue;
if (bytes_read > 0)
__write_all(stdout_fd, buffer, bytes_read);
}
/* Notify on error */
if (bytes_read < 0) {
guac_protocol_send_error(socket, "Error reading data.");
guac_socket_flush(socket);
return NULL;
}
/* Wait for input thread to die */
pthread_join(input_thread, NULL);
guac_client_log_info(client, "SSH connection ended.");
return NULL;
}