1 /*
2 * Copyright (c) 2013 Lukasz Marek <lukasz.m.luki@gmail.com>
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #include <fcntl.h>
22 #define LIBSSH_STATIC
23 #include <libssh/sftp.h>
24 #include "libavutil/avstring.h"
25 #include "libavutil/opt.h"
26 #include "libavutil/attributes.h"
27 #include "libavformat/avio.h"
28 #include "avformat.h"
29 #include "internal.h"
30 #include "url.h"
31
32 typedef struct {
33 const AVClass *class;
34 ssh_session session;
35 sftp_session sftp;
36 sftp_file file;
37 sftp_dir dir;
38 int64_t filesize;
39 int rw_timeout;
40 int trunc;
41 char *priv_key;
42 } LIBSSHContext;
43
libssh_create_ssh_session(LIBSSHContext * libssh,const char * hostname,unsigned int port)44 static av_cold int libssh_create_ssh_session(LIBSSHContext *libssh, const char* hostname, unsigned int port)
45 {
46 static const int verbosity = SSH_LOG_NOLOG;
47
48 if (!(libssh->session = ssh_new())) {
49 av_log(libssh, AV_LOG_ERROR, "SSH session creation failed: %s\n", ssh_get_error(libssh->session));
50 return AVERROR(ENOMEM);
51 }
52 ssh_options_set(libssh->session, SSH_OPTIONS_HOST, hostname);
53 ssh_options_set(libssh->session, SSH_OPTIONS_PORT, &port);
54 ssh_options_set(libssh->session, SSH_OPTIONS_LOG_VERBOSITY, &verbosity);
55 if (libssh->rw_timeout > 0) {
56 long timeout = libssh->rw_timeout * 1000;
57 ssh_options_set(libssh->session, SSH_OPTIONS_TIMEOUT_USEC, &timeout);
58 }
59
60 if (ssh_options_parse_config(libssh->session, NULL) < 0) {
61 av_log(libssh, AV_LOG_WARNING, "Could not parse the config file.\n");
62 }
63
64 if (ssh_connect(libssh->session) != SSH_OK) {
65 av_log(libssh, AV_LOG_ERROR, "Connection failed: %s\n", ssh_get_error(libssh->session));
66 return AVERROR(EIO);
67 }
68
69 return 0;
70 }
71
libssh_authentication(LIBSSHContext * libssh,const char * user,const char * password)72 static av_cold int libssh_authentication(LIBSSHContext *libssh, const char *user, const char *password)
73 {
74 int authorized = 0;
75 int auth_methods;
76
77 if (user)
78 ssh_options_set(libssh->session, SSH_OPTIONS_USER, user);
79
80 if (ssh_userauth_none(libssh->session, NULL) == SSH_AUTH_SUCCESS)
81 return 0;
82
83 auth_methods = ssh_userauth_list(libssh->session, NULL);
84
85 if (auth_methods & SSH_AUTH_METHOD_PUBLICKEY) {
86 if (libssh->priv_key) {
87 ssh_string pub_key;
88 ssh_private_key priv_key;
89 int type;
90 if (!ssh_try_publickey_from_file(libssh->session, libssh->priv_key, &pub_key, &type)) {
91 priv_key = privatekey_from_file(libssh->session, libssh->priv_key, type, password);
92 if (ssh_userauth_pubkey(libssh->session, NULL, pub_key, priv_key) == SSH_AUTH_SUCCESS) {
93 av_log(libssh, AV_LOG_DEBUG, "Authentication successful with selected private key.\n");
94 authorized = 1;
95 }
96 } else {
97 av_log(libssh, AV_LOG_DEBUG, "Invalid key is provided.\n");
98 return AVERROR(EACCES);
99 }
100 } else if (ssh_userauth_autopubkey(libssh->session, password) == SSH_AUTH_SUCCESS) {
101 av_log(libssh, AV_LOG_DEBUG, "Authentication successful with auto selected key.\n");
102 authorized = 1;
103 }
104 }
105
106 if (!authorized && password && (auth_methods & SSH_AUTH_METHOD_PASSWORD)) {
107 if (ssh_userauth_password(libssh->session, NULL, password) == SSH_AUTH_SUCCESS) {
108 av_log(libssh, AV_LOG_DEBUG, "Authentication successful with password.\n");
109 authorized = 1;
110 }
111 }
112
113 if (!authorized) {
114 av_log(libssh, AV_LOG_ERROR, "Authentication failed.\n");
115 return AVERROR(EACCES);
116 }
117
118 return 0;
119 }
120
libssh_create_sftp_session(LIBSSHContext * libssh)121 static av_cold int libssh_create_sftp_session(LIBSSHContext *libssh)
122 {
123 if (!(libssh->sftp = sftp_new(libssh->session))) {
124 av_log(libssh, AV_LOG_ERROR, "SFTP session creation failed: %s\n", ssh_get_error(libssh->session));
125 return AVERROR(ENOMEM);
126 }
127
128 if (sftp_init(libssh->sftp) != SSH_OK) {
129 av_log(libssh, AV_LOG_ERROR, "Error initializing sftp session: %s\n", ssh_get_error(libssh->session));
130 return AVERROR(EIO);
131 }
132
133 return 0;
134 }
135
libssh_open_file(LIBSSHContext * libssh,int flags,const char * file)136 static av_cold int libssh_open_file(LIBSSHContext *libssh, int flags, const char *file)
137 {
138 int access;
139
140 if ((flags & AVIO_FLAG_WRITE) && (flags & AVIO_FLAG_READ)) {
141 access = O_CREAT | O_RDWR;
142 if (libssh->trunc)
143 access |= O_TRUNC;
144 } else if (flags & AVIO_FLAG_WRITE) {
145 access = O_CREAT | O_WRONLY;
146 if (libssh->trunc)
147 access |= O_TRUNC;
148 } else
149 access = O_RDONLY;
150
151 /* 0666 = -rw-rw-rw- = read+write for everyone, minus umask */
152 if (!(libssh->file = sftp_open(libssh->sftp, file, access, 0666))) {
153 av_log(libssh, AV_LOG_ERROR, "Error opening sftp file: %s\n", ssh_get_error(libssh->session));
154 return AVERROR(EIO);
155 }
156
157 return 0;
158 }
159
libssh_stat_file(LIBSSHContext * libssh)160 static av_cold void libssh_stat_file(LIBSSHContext *libssh)
161 {
162 sftp_attributes stat;
163
164 if (!(stat = sftp_fstat(libssh->file))) {
165 av_log(libssh, AV_LOG_WARNING, "Cannot stat remote file.\n");
166 libssh->filesize = -1;
167 } else {
168 libssh->filesize = stat->size;
169 sftp_attributes_free(stat);
170 }
171 }
172
libssh_close(URLContext * h)173 static av_cold int libssh_close(URLContext *h)
174 {
175 LIBSSHContext *libssh = h->priv_data;
176 if (libssh->file) {
177 sftp_close(libssh->file);
178 libssh->file = NULL;
179 }
180 if (libssh->sftp) {
181 sftp_free(libssh->sftp);
182 libssh->sftp = NULL;
183 }
184 if (libssh->session) {
185 ssh_disconnect(libssh->session);
186 ssh_free(libssh->session);
187 libssh->session = NULL;
188 }
189 return 0;
190 }
191
libssh_connect(URLContext * h,const char * url,char * path,size_t path_size)192 static av_cold int libssh_connect(URLContext *h, const char *url, char *path, size_t path_size)
193 {
194 LIBSSHContext *libssh = h->priv_data;
195 char proto[10], hostname[1024], credencials[1024];
196 int port = 22, ret;
197 const char *user = NULL, *pass = NULL;
198 char *end = NULL;
199
200 av_url_split(proto, sizeof(proto),
201 credencials, sizeof(credencials),
202 hostname, sizeof(hostname),
203 &port,
204 path, path_size,
205 url);
206
207 if (!(*path))
208 av_strlcpy(path, "/", path_size);
209
210 // a port of 0 will use a port from ~/.ssh/config or the default value 22
211 if (port < 0 || port > 65535)
212 port = 0;
213
214 if ((ret = libssh_create_ssh_session(libssh, hostname, port)) < 0)
215 return ret;
216
217 user = av_strtok(credencials, ":", &end);
218 pass = av_strtok(end, ":", &end);
219
220 if ((ret = libssh_authentication(libssh, user, pass)) < 0)
221 return ret;
222
223 if ((ret = libssh_create_sftp_session(libssh)) < 0)
224 return ret;
225
226 return 0;
227 }
228
libssh_open(URLContext * h,const char * url,int flags)229 static av_cold int libssh_open(URLContext *h, const char *url, int flags)
230 {
231 int ret;
232 LIBSSHContext *libssh = h->priv_data;
233 char path[MAX_URL_SIZE];
234
235 if ((ret = libssh_connect(h, url, path, sizeof(path))) < 0)
236 goto fail;
237
238 if ((ret = libssh_open_file(libssh, flags, path)) < 0)
239 goto fail;
240
241 libssh_stat_file(libssh);
242
243 return 0;
244
245 fail:
246 libssh_close(h);
247 return ret;
248 }
249
libssh_seek(URLContext * h,int64_t pos,int whence)250 static int64_t libssh_seek(URLContext *h, int64_t pos, int whence)
251 {
252 LIBSSHContext *libssh = h->priv_data;
253 int64_t newpos;
254
255 if (libssh->filesize == -1 && (whence == AVSEEK_SIZE || whence == SEEK_END)) {
256 av_log(h, AV_LOG_ERROR, "Error during seeking.\n");
257 return AVERROR(EIO);
258 }
259
260 switch(whence) {
261 case AVSEEK_SIZE:
262 return libssh->filesize;
263 case SEEK_SET:
264 newpos = pos;
265 break;
266 case SEEK_CUR:
267 newpos = sftp_tell64(libssh->file) + pos;
268 break;
269 case SEEK_END:
270 newpos = libssh->filesize + pos;
271 break;
272 default:
273 return AVERROR(EINVAL);
274 }
275
276 if (newpos < 0) {
277 av_log(h, AV_LOG_ERROR, "Seeking to nagative position.\n");
278 return AVERROR(EINVAL);
279 }
280
281 if (sftp_seek64(libssh->file, newpos)) {
282 av_log(h, AV_LOG_ERROR, "Error during seeking.\n");
283 return AVERROR(EIO);
284 }
285
286 return newpos;
287 }
288
libssh_read(URLContext * h,unsigned char * buf,int size)289 static int libssh_read(URLContext *h, unsigned char *buf, int size)
290 {
291 LIBSSHContext *libssh = h->priv_data;
292 int bytes_read;
293
294 if ((bytes_read = sftp_read(libssh->file, buf, size)) < 0) {
295 av_log(libssh, AV_LOG_ERROR, "Read error.\n");
296 return AVERROR(EIO);
297 }
298 return bytes_read ? bytes_read : AVERROR_EOF;
299 }
300
libssh_write(URLContext * h,const unsigned char * buf,int size)301 static int libssh_write(URLContext *h, const unsigned char *buf, int size)
302 {
303 LIBSSHContext *libssh = h->priv_data;
304 int bytes_written;
305
306 if ((bytes_written = sftp_write(libssh->file, buf, size)) < 0) {
307 av_log(libssh, AV_LOG_ERROR, "Write error.\n");
308 return AVERROR(EIO);
309 }
310 return bytes_written;
311 }
312
libssh_open_dir(URLContext * h)313 static int libssh_open_dir(URLContext *h)
314 {
315 LIBSSHContext *libssh = h->priv_data;
316 int ret;
317 char path[MAX_URL_SIZE];
318
319 if ((ret = libssh_connect(h, h->filename, path, sizeof(path))) < 0)
320 goto fail;
321
322 if (!(libssh->dir = sftp_opendir(libssh->sftp, path))) {
323 av_log(libssh, AV_LOG_ERROR, "Error opening sftp dir: %s\n", ssh_get_error(libssh->session));
324 ret = AVERROR(EIO);
325 goto fail;
326 }
327
328 return 0;
329
330 fail:
331 libssh_close(h);
332 return ret;
333 }
334
libssh_read_dir(URLContext * h,AVIODirEntry ** next)335 static int libssh_read_dir(URLContext *h, AVIODirEntry **next)
336 {
337 LIBSSHContext *libssh = h->priv_data;
338 sftp_attributes attr = NULL;
339 AVIODirEntry *entry;
340
341 *next = entry = ff_alloc_dir_entry();
342 if (!entry)
343 return AVERROR(ENOMEM);
344
345 do {
346 if (attr)
347 sftp_attributes_free(attr);
348 attr = sftp_readdir(libssh->sftp, libssh->dir);
349 if (!attr) {
350 av_freep(next);
351 if (sftp_dir_eof(libssh->dir))
352 return 0;
353 return AVERROR(EIO);
354 }
355 } while (!strcmp(attr->name, ".") || !strcmp(attr->name, ".."));
356
357 entry->name = av_strdup(attr->name);
358 entry->group_id = attr->gid;
359 entry->user_id = attr->uid;
360 entry->size = attr->size;
361 entry->access_timestamp = INT64_C(1000000) * attr->atime;
362 entry->modification_timestamp = INT64_C(1000000) * attr->mtime;
363 entry->filemode = attr->permissions & 0777;
364 switch(attr->type) {
365 case SSH_FILEXFER_TYPE_REGULAR:
366 entry->type = AVIO_ENTRY_FILE;
367 break;
368 case SSH_FILEXFER_TYPE_DIRECTORY:
369 entry->type = AVIO_ENTRY_DIRECTORY;
370 break;
371 case SSH_FILEXFER_TYPE_SYMLINK:
372 entry->type = AVIO_ENTRY_SYMBOLIC_LINK;
373 break;
374 case SSH_FILEXFER_TYPE_SPECIAL:
375 /* Special type includes: sockets, char devices, block devices and pipes.
376 It is probably better to return unknown type, to not confuse anybody. */
377 case SSH_FILEXFER_TYPE_UNKNOWN:
378 default:
379 entry->type = AVIO_ENTRY_UNKNOWN;
380 }
381 sftp_attributes_free(attr);
382 return 0;
383 }
384
libssh_close_dir(URLContext * h)385 static int libssh_close_dir(URLContext *h)
386 {
387 LIBSSHContext *libssh = h->priv_data;
388 if (libssh->dir)
389 sftp_closedir(libssh->dir);
390 libssh->dir = NULL;
391 libssh_close(h);
392 return 0;
393 }
394
libssh_delete(URLContext * h)395 static int libssh_delete(URLContext *h)
396 {
397 int ret;
398 LIBSSHContext *libssh = h->priv_data;
399 sftp_attributes attr = NULL;
400 char path[MAX_URL_SIZE];
401
402 if ((ret = libssh_connect(h, h->filename, path, sizeof(path))) < 0)
403 goto cleanup;
404
405 if (!(attr = sftp_stat(libssh->sftp, path))) {
406 ret = AVERROR(sftp_get_error(libssh->sftp));
407 goto cleanup;
408 }
409
410 if (attr->type == SSH_FILEXFER_TYPE_DIRECTORY) {
411 if (sftp_rmdir(libssh->sftp, path) < 0) {
412 ret = AVERROR(sftp_get_error(libssh->sftp));
413 goto cleanup;
414 }
415 } else {
416 if (sftp_unlink(libssh->sftp, path) < 0) {
417 ret = AVERROR(sftp_get_error(libssh->sftp));
418 goto cleanup;
419 }
420 }
421
422 ret = 0;
423
424 cleanup:
425 if (attr)
426 sftp_attributes_free(attr);
427 libssh_close(h);
428 return ret;
429 }
430
libssh_move(URLContext * h_src,URLContext * h_dst)431 static int libssh_move(URLContext *h_src, URLContext *h_dst)
432 {
433 int ret;
434 LIBSSHContext *libssh = h_src->priv_data;
435 char path_src[MAX_URL_SIZE], path_dst[MAX_URL_SIZE];
436 char hostname_src[1024], hostname_dst[1024];
437 char credentials_src[1024], credentials_dst[1024];
438 int port_src = 22, port_dst = 22;
439
440 av_url_split(NULL, 0,
441 credentials_src, sizeof(credentials_src),
442 hostname_src, sizeof(hostname_src),
443 &port_src,
444 path_src, sizeof(path_src),
445 h_src->filename);
446
447 av_url_split(NULL, 0,
448 credentials_dst, sizeof(credentials_dst),
449 hostname_dst, sizeof(hostname_dst),
450 &port_dst,
451 path_dst, sizeof(path_dst),
452 h_dst->filename);
453
454 if (strcmp(credentials_src, credentials_dst) ||
455 strcmp(hostname_src, hostname_dst) ||
456 port_src != port_dst) {
457 return AVERROR(EINVAL);
458 }
459
460 if ((ret = libssh_connect(h_src, h_src->filename, path_src, sizeof(path_src))) < 0)
461 goto cleanup;
462
463 if (sftp_rename(libssh->sftp, path_src, path_dst) < 0) {
464 ret = AVERROR(sftp_get_error(libssh->sftp));
465 goto cleanup;
466 }
467
468 ret = 0;
469
470 cleanup:
471 libssh_close(h_src);
472 return ret;
473 }
474
475 #define OFFSET(x) offsetof(LIBSSHContext, x)
476 #define D AV_OPT_FLAG_DECODING_PARAM
477 #define E AV_OPT_FLAG_ENCODING_PARAM
478 static const AVOption options[] = {
479 {"timeout", "set timeout of socket I/O operations", OFFSET(rw_timeout), AV_OPT_TYPE_INT, {.i64 = -1}, -1, INT_MAX, D|E },
480 {"truncate", "Truncate existing files on write", OFFSET(trunc), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
481 {"private_key", "set path to private key", OFFSET(priv_key), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, D|E },
482 {NULL}
483 };
484
485 static const AVClass libssh_context_class = {
486 .class_name = "libssh",
487 .item_name = av_default_item_name,
488 .option = options,
489 .version = LIBAVUTIL_VERSION_INT,
490 };
491
492 const URLProtocol ff_libssh_protocol = {
493 .name = "sftp",
494 .url_open = libssh_open,
495 .url_read = libssh_read,
496 .url_write = libssh_write,
497 .url_seek = libssh_seek,
498 .url_close = libssh_close,
499 .url_delete = libssh_delete,
500 .url_move = libssh_move,
501 .url_open_dir = libssh_open_dir,
502 .url_read_dir = libssh_read_dir,
503 .url_close_dir = libssh_close_dir,
504 .priv_data_size = sizeof(LIBSSHContext),
505 .priv_data_class = &libssh_context_class,
506 .flags = URL_PROTOCOL_FLAG_NETWORK,
507 };
508