guacamole-spice-protocol/src/protocols/ssh/ssh_client.c
2013-10-30 23:19:11 -07:00

364 lines
11 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 <libssh/libssh.h>
#include <libssh/sftp.h>
#include "client.h"
#include "common.h"
#include "guac_handlers.h"
#include "sftp.h"
/**
* 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->term->stdin_pipe_fd[0];
int stdout_fd = client_data->term->stdout_pipe_fd[1];
/* Print title */
guac_terminal_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 == 0x7F) {
if (pos > 0) {
guac_terminal_write_all(stdout_fd, "\b \b", 3);
pos--;
}
}
/* CR (end of input */
else if (in_byte == 0x0D) {
guac_terminal_write_all(stdout_fd, "\r\n", 2);
break;
}
else {
/* Store character, update buffers */
str[pos++] = in_byte;
/* Print character if echoing */
if (echo)
guac_terminal_write_all(stdout_fd, &in_byte, 1);
else
guac_terminal_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->term->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;
}
static ssh_session __guac_ssh_create_session(guac_client* client) {
ssh_guac_client_data* client_data = (ssh_guac_client_data*) client->data;
/* Open SSH session */
ssh_session session = ssh_new();
if (session == NULL) {
guac_client_log_error(client, "Session allocation failed",
ssh_get_error(session));
return NULL;
}
/* Set session options */
ssh_options_set(session, SSH_OPTIONS_HOST, client_data->hostname);
ssh_options_set(session, SSH_OPTIONS_PORT, &(client_data->port));
ssh_options_set(session, SSH_OPTIONS_USER, client_data->username);
/* Connect */
if (ssh_connect(session) != SSH_OK) {
guac_client_log_error(client, "Unable to connect via SSH: %s",
ssh_get_error(session));
return NULL;
}
#ifdef ENABLE_SSH_PUBLIC_KEY
/* Authenticate with key if available */
if (client_data->key != NULL) {
if (ssh_userauth_publickey(session, NULL, client_data->key)
== SSH_AUTH_SUCCESS)
return session;
else {
guac_client_log_error(client,
"Public key authentication failed: %s",
ssh_get_error(session));
return NULL;
}
}
#endif
/* Authenticate with password */
if (ssh_userauth_password(session, NULL, client_data->password)
== SSH_AUTH_SUCCESS)
return session;
else {
guac_client_log_error(client,
"Password authentication failed: %s",
ssh_get_error(session));
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;
char name[1024];
guac_socket* socket = client->socket;
char buffer[8192];
int bytes_read = -1234;
int stdout_fd = client_data->term->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;
/* Send new name */
snprintf(name, sizeof(name)-1, "%s@%s", client_data->username, client_data->hostname);
guac_protocol_send_name(socket, name);
#ifdef ENABLE_SSH_PUBLIC_KEY
/* If key specified, import */
if (client_data->key_base64[0] != 0) {
/* Attempt to read key without passphrase */
if (ssh_pki_import_privkey_base64(client_data->key_base64, NULL,
NULL, NULL, &client_data->key) == SSH_OK)
guac_client_log_info(client, "Auth key successfully imported.");
/* On failure, attempt with passphrase */
else {
/* Prompt for passphrase if missing */
if (client_data->key_passphrase[0] == 0) {
if (prompt(client, "Key passphrase: ",
client_data->key_passphrase,
sizeof(client_data->key_passphrase), false) == NULL)
return NULL;
}
/* Import key with passphrase */
if (ssh_pki_import_privkey_base64(client_data->key_base64,
client_data->key_passphrase,
NULL, NULL, &client_data->key) != SSH_OK) {
guac_client_log_error(client, "Auth key import failed.");
return NULL;
}
} /* end decrypt key with passphrase */
} /* end if key given */
/* Otherwise, get password if not provided */
else if (client_data->password[0] == 0) {
#else
/* Get password if not provided */
if (client_data->password[0] == 0) {
#endif
if (prompt(client, "Password: ", client_data->password,
sizeof(client_data->password), false) == NULL)
return NULL;
}
/* Clear screen */
guac_terminal_write_all(stdout_fd, "\x1B[H\x1B[J", 6);
/* Open SSH session */
client_data->session = __guac_ssh_create_session(client);
if (client_data->session == NULL) {
guac_protocol_send_error(socket, "Unable to create SSH session.",
GUAC_PROTOCOL_STATUS_INTERNAL_ERROR);
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_PROTOCOL_STATUS_INTERNAL_ERROR);
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_PROTOCOL_STATUS_INTERNAL_ERROR);
guac_socket_flush(socket);
return NULL;
}
/* Start SFTP session as well, if enabled */
if (client_data->enable_sftp) {
/* Create SSH session specific for SFTP */
client_data->sftp_ssh_session = __guac_ssh_create_session(client);
/* Request SFTP */
client_data->sftp_session = sftp_new(client_data->sftp_ssh_session);
if (client_data->sftp_session == NULL) {
guac_protocol_send_error(socket, "Unable to start SFTP session..",
GUAC_PROTOCOL_STATUS_INTERNAL_ERROR);
guac_socket_flush(socket);
return NULL;
}
/* Init SFTP */
if (sftp_init(client_data->sftp_session) != SSH_OK) {
guac_protocol_send_error(socket, "Unable to initialize SFTP session.",
GUAC_PROTOCOL_STATUS_INTERNAL_ERROR);
guac_socket_flush(socket);
return NULL;
}
/* Set file handlers */
client->ack_handler = guac_sftp_ack_handler;
client->file_handler = guac_sftp_file_handler;
client->blob_handler = guac_sftp_blob_handler;
client->end_handler = guac_sftp_end_handler;
guac_client_log_info(client, "SFTP session initialized");
}
/* Request PTY */
if (channel_request_pty_size(client_data->term_channel, "linux",
client_data->term->term_width, client_data->term->term_height) != SSH_OK) {
guac_protocol_send_error(socket, "Unable to allocate PTY for channel.",
GUAC_PROTOCOL_STATUS_INTERNAL_ERROR);
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_PROTOCOL_STATUS_INTERNAL_ERROR);
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;
/* Attempt to write data received. Exit on failure. */
if (bytes_read > 0) {
int written = guac_terminal_write_all(stdout_fd, buffer, bytes_read);
if (written < 0)
break;
}
}
/* Wait for input thread to die */
pthread_join(input_thread, NULL);
guac_client_log_info(client, "SSH connection ended.");
return NULL;
}