guacamole-spice-protocol/src/protocols/ssh/sftp.c
2013-10-28 14:11:04 -07:00

294 lines
8.8 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):
*
* 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 <unistd.h>
#include <libgen.h>
#include <sys/stat.h>
#include <stdbool.h>
#include <string.h>
#include <fcntl.h>
#include <libssh/libssh.h>
#include <libssh/sftp.h>
#include <guacamole/client.h>
#include <guacamole/protocol.h>
#include <guacamole/stream.h>
#include "client.h"
static bool __ssh_guac_valid_filename(char* filename) {
/* Disallow "." as a filename */
if (strcmp(filename, ".") == 0)
return false;
/* Disallow ".." as a filename */
if (strcmp(filename, "..") == 0)
return false;
/* Search for path separator characters */
for (;;) {
char c = *(filename++);
if (c == '\0')
break;
/* Replace slashes with underscores */
if (c == '\\' || c == '/')
return false;
}
/* If filename does not contain a path, it's ok */
return true;
}
int guac_sftp_file_handler(guac_client* client, guac_stream* stream,
char* mimetype, char* filename) {
ssh_guac_client_data* client_data = (ssh_guac_client_data*) client->data;
char fullpath[GUAC_SFTP_MAX_PATH];
sftp_file file;
int i;
/* Ensure filename is a valid filename and not a path */
if (!__ssh_guac_valid_filename(filename)) {
guac_protocol_send_ack(client->socket, stream,
"SFTP: Illegal filename",
GUAC_PROTOCOL_STATUS_INVALID_PARAMETER);
guac_socket_flush(client->socket);
return 0;
}
/* Copy upload path, append trailing slash */
for (i=0; i<GUAC_SFTP_MAX_PATH; i++) {
char c = client_data->sftp_upload_path[i];
if (c == '\0') {
fullpath[i++] = '/';
break;
}
fullpath[i] = c;
}
/* Append filename */
for (; i<GUAC_SFTP_MAX_PATH; i++) {
char c = *(filename++);
if (c == '\0')
break;
fullpath[i] = c;
}
/* If path + filename exceeds max length, abort */
if (i == GUAC_SFTP_MAX_PATH) {
guac_protocol_send_ack(client->socket, stream, "SFTP: Name too long",
GUAC_PROTOCOL_STATUS_INVALID_PARAMETER);
guac_socket_flush(client->socket);
return 0;
}
/* Terminate path string */
fullpath[i] = '\0';
/* Open file via SFTP */
file = sftp_open(client_data->sftp_session, fullpath,
O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR);
/* Inform of status */
if (file != NULL) {
guac_protocol_send_ack(client->socket, stream, "SFTP: File opened",
GUAC_PROTOCOL_STATUS_SUCCESS);
guac_socket_flush(client->socket);
}
else {
guac_client_log_error(client, "Unable to open file \"%s\": %s",
fullpath, ssh_get_error(client_data->sftp_ssh_session));
guac_protocol_send_ack(client->socket, stream, "SFTP: Open failed",
GUAC_PROTOCOL_STATUS_INTERNAL_ERROR);
guac_socket_flush(client->socket);
}
/* Store file within stream */
stream->data = file;
return 0;
}
int guac_sftp_blob_handler(guac_client* client, guac_stream* stream,
void* data, int length) {
/* Pull file from stream */
ssh_guac_client_data* client_data = (ssh_guac_client_data*) client->data;
sftp_file file = (sftp_file) stream->data;
/* Attempt write */
if (sftp_write(file, data, length) == length) {
guac_protocol_send_ack(client->socket, stream, "SFTP: OK",
GUAC_PROTOCOL_STATUS_SUCCESS);
guac_socket_flush(client->socket);
}
/* Inform of any errors */
else {
guac_client_log_error(client, "Unable to write to file: %s",
ssh_get_error(client_data->sftp_ssh_session));
guac_protocol_send_ack(client->socket, stream, "SFTP: Write failed",
GUAC_PROTOCOL_STATUS_INTERNAL_ERROR);
guac_socket_flush(client->socket);
}
return 0;
}
int guac_sftp_end_handler(guac_client* client, guac_stream* stream) {
/* Pull file from stream */
sftp_file file = (sftp_file) stream->data;
/* Attempt to close file */
if (sftp_close(file) == SSH_OK) {
guac_protocol_send_ack(client->socket, stream, "SFTP: OK",
GUAC_PROTOCOL_STATUS_SUCCESS);
guac_socket_flush(client->socket);
}
else {
guac_client_log_error(client, "Unable to close file");
guac_protocol_send_ack(client->socket, stream, "SFTP: Close failed",
GUAC_PROTOCOL_STATUS_INTERNAL_ERROR);
guac_socket_flush(client->socket);
}
return 0;
}
int guac_sftp_ack_handler(guac_client* client, guac_stream* stream,
char* message, guac_protocol_status status) {
ssh_guac_client_data* client_data = (ssh_guac_client_data*) client->data;
sftp_file file = (sftp_file) stream->data;
/* If successful, read data */
if (status == GUAC_PROTOCOL_STATUS_SUCCESS) {
/* Attempt read into buffer */
char buffer[4096];
int bytes_read = sftp_read(file, buffer, sizeof(buffer));
/* If bytes read, send as blob */
if (bytes_read > 0)
guac_protocol_send_blob(client->socket, stream,
buffer, bytes_read);
/* If EOF, send end */
else if (bytes_read == 0) {
guac_protocol_send_end(client->socket, stream);
guac_client_free_stream(client, stream);
}
/* Otherwise, fail stream */
else {
guac_client_log_error(client, "Error reading file: %s",
ssh_get_error(client_data->sftp_ssh_session));
guac_protocol_send_end(client->socket, stream);
guac_client_free_stream(client, stream);
}
guac_socket_flush(client->socket);
}
/* Otherwise, return stream to client */
else
guac_client_free_stream(client, stream);
return 0;
}
guac_stream* guac_sftp_download_file(guac_client* client,
char* filename) {
ssh_guac_client_data* client_data = (ssh_guac_client_data*) client->data;
guac_stream* stream;
sftp_file file;
/* Attempt to open file for reading */
file = sftp_open(client_data->sftp_session, filename, O_RDONLY, 0);
if (file == NULL) {
guac_client_log_error(client, "Unable to read file \"%s\": %s",
filename, ssh_get_error(client_data->sftp_ssh_session));
return NULL;
}
/* Allocate stream */
stream = guac_client_alloc_stream(client);
stream->data = file;
/* Send stream start, strip name */
filename = basename(filename);
guac_protocol_send_file(client->socket, stream,
"application/octet-stream", filename);
guac_socket_flush(client->socket);
return stream;
}
void guac_sftp_set_upload_path(guac_client* client, char* path) {
ssh_guac_client_data* client_data = (ssh_guac_client_data*) client->data;
int length = strnlen(path, GUAC_SFTP_MAX_PATH);
/* Ignore requests which exceed maximum-allowed path */
if (length > GUAC_SFTP_MAX_PATH) {
guac_client_log_error(client,
"Submitted path exceeds limit of %i bytes",
GUAC_SFTP_MAX_PATH);
return;
}
/* Copy path */
memcpy(client_data->sftp_upload_path, path, length);
}