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];
pthread_t input_thread;
/* Init SSH base libraries */
if (guac_common_ssh_init(client))
return NULL;
/* Get user and credentials */
client_data->user = guac_ssh_get_user(client);
/* Send new name */
char name[1024];
snprintf(name, sizeof(name)-1, "%s@%s",
client_data->username, client_data->hostname);
guac_protocol_send_name(socket, name);
/* Open SSH session */
client_data->session = guac_common_ssh_create_session(client,
client_data->hostname, client_data->port, client_data->user);
if (client_data->session == NULL) {
/* Already aborted within guac_common_ssh_create_session() */
return NULL;
}
pthread_mutex_init(&client_data->term_channel_lock, NULL);
/* Open channel for terminal */
client_data->term_channel =
libssh2_channel_open_session(client_data->session->session);
if (client_data->term_channel == NULL) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_ERROR,
"Unable to open terminal channel.");
return NULL;
}
#ifdef ENABLE_SSH_AGENT
/* Start SSH agent forwarding, if enabled */
if (client_data->enable_agent) {
libssh2_session_callback_set(client_data->session,
LIBSSH2_CALLBACK_AUTH_AGENT, (void*) ssh_auth_agent_callback);
/* Request agent forwarding */
if (libssh2_channel_request_auth_agent(client_data->term_channel))
guac_client_log(client, GUAC_LOG_ERROR, "Agent forwarding request failed");
else
guac_client_log(client, GUAC_LOG_INFO, "Agent forwarding enabled.");
}
client_data->auth_agent = NULL;
#endif
/* Start SFTP session as well, if enabled */
if (client_data->enable_sftp) {
/* Create SSH session specific for SFTP */
guac_client_log(client, GUAC_LOG_DEBUG, "Reconnecting for SFTP...");
client_data->sftp_session =
guac_common_ssh_create_session(client, client_data->hostname,
client_data->port, client_data->user);
if (client_data->sftp_session == NULL) {
/* Already aborted within guac_common_ssh_create_session() */
return NULL;
}
/* Request SFTP */
client_data->sftp_filesystem =
guac_common_ssh_create_sftp_filesystem(
client_data->sftp_session, "/");
/* Set generic (non-filesystem) file upload handler */
client->file_handler = guac_sftp_file_handler;
/* Init handlers for Guacamole-specific console codes */
client_data->term->upload_path_handler = guac_sftp_set_upload_path;
client_data->term->file_download_handler = guac_sftp_download_file;
guac_client_log(client, GUAC_LOG_DEBUG, "SFTP session initialized");
}
/* Request PTY */
if (libssh2_channel_request_pty_ex(client_data->term_channel, "linux", sizeof("linux")-1, NULL, 0,
client_data->term->term_width, client_data->term->term_height, 0, 0)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_ERROR, "Unable to allocate PTY.");
return NULL;
}
/* Request shell */
if (libssh2_channel_shell(client_data->term_channel)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_ERROR, "Unable to associate shell with PTY.");
return NULL;
}
/* Logged in */
guac_client_log(client, GUAC_LOG_INFO, "SSH connection successful.");
/* Start input thread */
if (pthread_create(&(input_thread), NULL, ssh_input_thread, (void*) client)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR, "Unable to start input thread");
return NULL;
}
/* Set non-blocking */
libssh2_session_set_blocking(client_data->session->session, 0);
/* While data available, write to terminal */
int bytes_read = 0;
for (;;) {
/* Track total amount of data read */
int total_read = 0;
pthread_mutex_lock(&(client_data->term_channel_lock));
/* Stop reading at EOF */
if (libssh2_channel_eof(client_data->term_channel)) {
pthread_mutex_unlock(&(client_data->term_channel_lock));
break;
}
/* Read terminal data */
bytes_read = libssh2_channel_read(client_data->term_channel,
buffer, sizeof(buffer));
pthread_mutex_unlock(&(client_data->term_channel_lock));
/* Attempt to write data received. Exit on failure. */
if (bytes_read > 0) {
int written = guac_terminal_write_stdout(client_data->term, buffer, bytes_read);
if (written < 0)
break;
total_read += bytes_read;
}
else if (bytes_read < 0 && bytes_read != LIBSSH2_ERROR_EAGAIN)
break;
#ifdef ENABLE_SSH_AGENT
/* If agent open, handle any agent packets */
if (client_data->auth_agent != NULL) {
bytes_read = ssh_auth_agent_read(client_data->auth_agent);
if (bytes_read > 0)
total_read += bytes_read;
else if (bytes_read < 0 && bytes_read != LIBSSH2_ERROR_EAGAIN)
client_data->auth_agent = NULL;
}
#endif
/* Wait for more data if reads turn up empty */
if (total_read == 0) {
fd_set fds;
struct timeval timeout;
FD_ZERO(&fds);
FD_SET(client_data->session->fd, &fds);
/* Wait for one second */
timeout.tv_sec = 1;
timeout.tv_usec = 0;
if (select(client_data->session->fd + 1, &fds,
NULL, NULL, &timeout) < 0)
break;
}
}
/* Kill client and Wait for input thread to die */
guac_client_stop(client);
pthread_join(input_thread, NULL);
pthread_mutex_destroy(&client_data->term_channel_lock);
guac_client_log(client, GUAC_LOG_INFO, "SSH connection ended.");
return NULL;
}
void* ssh_client_thread(void* data) {
guac_client* client = (guac_client*) data;
guac_ssh_client* ssh_client = (guac_ssh_client*) client->data;
guac_ssh_settings* settings = ssh_client->settings;
char buffer[8192];
pthread_t input_thread;
/* Init SSH base libraries */
if (guac_common_ssh_init(client)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
"SSH library initialization failed");
return NULL;
}
/* Set up screen recording, if requested */
if (settings->recording_path != NULL) {
guac_common_recording_create(client,
settings->recording_path,
settings->recording_name,
settings->create_recording_path);
}
/* Create terminal */
ssh_client->term = guac_terminal_create(client,
settings->font_name, settings->font_size,
settings->resolution, settings->width, settings->height,
settings->color_scheme);
/* Fail if terminal init failed */
if (ssh_client->term == NULL) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
"Terminal initialization failed");
return NULL;
}
/* Set up typescript, if requested */
if (settings->typescript_path != NULL) {
guac_terminal_create_typescript(ssh_client->term,
settings->typescript_path,
settings->typescript_name,
settings->create_typescript_path);
}
/* Get user and credentials */
ssh_client->user = guac_ssh_get_user(client);
/* Open SSH session */
ssh_client->session = guac_common_ssh_create_session(client,
settings->hostname, settings->port, ssh_client->user);
if (ssh_client->session == NULL) {
/* Already aborted within guac_common_ssh_create_session() */
return NULL;
}
pthread_mutex_init(&ssh_client->term_channel_lock, NULL);
/* Open channel for terminal */
ssh_client->term_channel =
libssh2_channel_open_session(ssh_client->session->session);
if (ssh_client->term_channel == NULL) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_ERROR,
"Unable to open terminal channel.");
return NULL;
}
#ifdef ENABLE_SSH_AGENT
/* Start SSH agent forwarding, if enabled */
if (ssh_client->enable_agent) {
libssh2_session_callback_set(ssh_client->session,
LIBSSH2_CALLBACK_AUTH_AGENT, (void*) ssh_auth_agent_callback);
/* Request agent forwarding */
if (libssh2_channel_request_auth_agent(ssh_client->term_channel))
guac_client_log(client, GUAC_LOG_ERROR, "Agent forwarding request failed");
else
guac_client_log(client, GUAC_LOG_INFO, "Agent forwarding enabled.");
}
ssh_client->auth_agent = NULL;
#endif
/* Start SFTP session as well, if enabled */
if (settings->enable_sftp) {
/* Create SSH session specific for SFTP */
guac_client_log(client, GUAC_LOG_DEBUG, "Reconnecting for SFTP...");
ssh_client->sftp_session =
guac_common_ssh_create_session(client, settings->hostname,
settings->port, ssh_client->user);
if (ssh_client->sftp_session == NULL) {
/* Already aborted within guac_common_ssh_create_session() */
return NULL;
}
/* Request SFTP */
ssh_client->sftp_filesystem = guac_common_ssh_create_sftp_filesystem(
ssh_client->sftp_session, "/");
/* Expose filesystem to connection owner */
guac_client_for_owner(client,
guac_common_ssh_expose_sftp_filesystem,
ssh_client->sftp_filesystem);
/* Init handlers for Guacamole-specific console codes */
ssh_client->term->upload_path_handler = guac_sftp_set_upload_path;
ssh_client->term->file_download_handler = guac_sftp_download_file;
guac_client_log(client, GUAC_LOG_DEBUG, "SFTP session initialized");
}
/* Request PTY */
if (libssh2_channel_request_pty_ex(ssh_client->term_channel, "linux", sizeof("linux")-1, NULL, 0,
ssh_client->term->term_width, ssh_client->term->term_height, 0, 0)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_ERROR, "Unable to allocate PTY.");
return NULL;
}
/* If a command is specified, run that instead of a shell */
if (settings->command != NULL) {
if (libssh2_channel_exec(ssh_client->term_channel, settings->command)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_ERROR,
"Unable to execute command.");
return NULL;
}
}
/* Otherwise, request a shell */
else if (libssh2_channel_shell(ssh_client->term_channel)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_ERROR,
"Unable to associate shell with PTY.");
return NULL;
}
/* Logged in */
guac_client_log(client, GUAC_LOG_INFO, "SSH connection successful.");
/* Start input thread */
if (pthread_create(&(input_thread), NULL, ssh_input_thread, (void*) client)) {
guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR, "Unable to start input thread");
return NULL;
}
/* Set non-blocking */
libssh2_session_set_blocking(ssh_client->session->session, 0);
/* While data available, write to terminal */
int bytes_read = 0;
for (;;) {
/* Track total amount of data read */
int total_read = 0;
pthread_mutex_lock(&(ssh_client->term_channel_lock));
/* Stop reading at EOF */
if (libssh2_channel_eof(ssh_client->term_channel)) {
pthread_mutex_unlock(&(ssh_client->term_channel_lock));
break;
}
/* Read terminal data */
bytes_read = libssh2_channel_read(ssh_client->term_channel,
buffer, sizeof(buffer));
pthread_mutex_unlock(&(ssh_client->term_channel_lock));
/* Attempt to write data received. Exit on failure. */
if (bytes_read > 0) {
int written = guac_terminal_write_stdout(ssh_client->term, buffer, bytes_read);
if (written < 0)
break;
total_read += bytes_read;
}
else if (bytes_read < 0 && bytes_read != LIBSSH2_ERROR_EAGAIN)
break;
#ifdef ENABLE_SSH_AGENT
/* If agent open, handle any agent packets */
if (ssh_client->auth_agent != NULL) {
bytes_read = ssh_auth_agent_read(ssh_client->auth_agent);
if (bytes_read > 0)
total_read += bytes_read;
else if (bytes_read < 0 && bytes_read != LIBSSH2_ERROR_EAGAIN)
ssh_client->auth_agent = NULL;
}
#endif
/* Wait for more data if reads turn up empty */
if (total_read == 0) {
fd_set fds;
struct timeval timeout;
FD_ZERO(&fds);
FD_SET(ssh_client->session->fd, &fds);
/* Wait for one second */
timeout.tv_sec = 1;
timeout.tv_usec = 0;
if (select(ssh_client->session->fd + 1, &fds,
NULL, NULL, &timeout) < 0)
break;
}
}
/* Kill client and Wait for input thread to die */
guac_client_stop(client);
pthread_join(input_thread, NULL);
pthread_mutex_destroy(&ssh_client->term_channel_lock);
guac_client_log(client, GUAC_LOG_INFO, "SSH connection ended.");
return NULL;
}
