-
Notifications
You must be signed in to change notification settings - Fork 72
/
scp.c
437 lines (385 loc) · 14.2 KB
/
scp.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
/* Copyright (c) 2004-2006, Sara Golemon <sarag@libssh2.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms,
* with or without modification, are permitted provided
* that the following conditions are met:
*
* Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* Neither the name of the copyright holder nor the names
* of any other contributors may be used to endorse or
* promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*/
#include "libssh2_priv.h"
#include <errno.h>
#include <stdlib.h>
#define LIBSSH2_SCP_RESPONSE_BUFLEN 256
/* {{{ libssh2_scp_recv
* Open a channel and request a remote file via SCP
*/
LIBSSH2_API LIBSSH2_CHANNEL *libssh2_scp_recv(LIBSSH2_SESSION *session, const char *path, struct stat *sb)
{
int path_len = strlen(path);
unsigned char *command, response[LIBSSH2_SCP_RESPONSE_BUFLEN];
unsigned long command_len = path_len + sizeof("scp -f "), response_len;
LIBSSH2_CHANNEL *channel;
long mode = 0, size = 0, mtime = 0, atime = 0;
if (sb) {
command_len++;
}
command = LIBSSH2_ALLOC(session, command_len);
if (!command) {
libssh2_error(session, LIBSSH2_ERROR_ALLOC, "Unable to allocate a command buffer for scp session", 0);
return NULL;
}
if (sb) {
memcpy(command, "scp -pf ", sizeof("scp -pf ") - 1);
memcpy(command + sizeof("scp -pf ") - 1, path, path_len);
} else {
memcpy(command, "scp -f ", sizeof("scp -f ") - 1);
memcpy(command + sizeof("scp -f ") - 1, path, path_len);
}
command[command_len - 1] = '\0';
#ifdef LIBSSH2_DEBUG_SCP
_libssh2_debug(session, LIBSSH2_DBG_SCP, "Opening channel for SCP receive");
#endif
/* Allocate a channel */
if ((channel = libssh2_channel_open_session(session)) == NULL) {
LIBSSH2_FREE(session, command);
return NULL;
}
/* Use blocking I/O for negotiation phase */
libssh2_channel_set_blocking(channel, 1);
/* Request SCP for the desired file */
if (libssh2_channel_process_startup(channel, "exec", sizeof("exec") - 1, (const char *)command, command_len)) {
LIBSSH2_FREE(session, command);
libssh2_channel_free(channel);
return NULL;
}
LIBSSH2_FREE(session, command);
#ifdef LIBSSH2_DEBUG_SCP
_libssh2_debug(session, LIBSSH2_DBG_SCP, "Sending initial wakeup");
#endif
/* SCP ACK */
response[0] = '\0';
if (libssh2_channel_write(channel, response, 1) != 1) {
libssh2_channel_free(channel);
return NULL;
}
/* Parse SCP response */
response_len = 0;
while (sb && (response_len < LIBSSH2_SCP_RESPONSE_BUFLEN)) {
unsigned char *s, *p;
if (libssh2_channel_read(channel, response + response_len, 1) <= 0) {
/* Timeout, give up */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Timed out waiting for SCP response", 0);
libssh2_channel_free(channel);
return NULL;
}
response_len++;
if (response[0] != 'T') {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid data in SCP response, missing Time data", 0);
libssh2_channel_free(channel);
return NULL;
}
if ((response_len > 1) &&
((response[response_len-1] < '0') || (response[response_len-1] > '9')) &&
(response[response_len-1] != ' ') &&
(response[response_len-1] != '\r') &&
(response[response_len-1] != '\n')) {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid data in SCP response", 0);
libssh2_channel_free(channel);
return NULL;
}
if ((response_len < 9) || (response[response_len-1] != '\n')) {
if (response_len == LIBSSH2_SCP_RESPONSE_BUFLEN) {
/* You had your chance */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Unterminated response from SCP server", 0);
libssh2_channel_free(channel);
return NULL;
}
/* Way too short to be an SCP response, or not done yet, short circuit */
continue;
}
/* We're guaranteed not to go under response_len == 0 by the logic above */
while ((response[response_len-1] == '\r') || (response[response_len-1] == '\n')) response_len--;
response[response_len] = '\0';
if (response_len < 8) {
/* EOL came too soon */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, too short", 0);
libssh2_channel_free(channel);
return NULL;
}
s = response + 1;
p = (unsigned char *)strchr((const char *)s, ' ');
if (!p || ((p - s) <= 0)) {
/* No spaces or space in the wrong spot */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, malformed mtime", 0);
libssh2_channel_free(channel);
return NULL;
}
*(p++) = '\0';
/* Make sure we don't get fooled by leftover values */
errno = 0;
mtime = strtol((const char *)s, NULL, 10);
if (errno) {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, invalid mtime", 0);
libssh2_channel_free(channel);
return NULL;
}
s = (unsigned char *)strchr((const char *)p, ' ');
if (!s || ((s - p) <= 0)) {
/* No spaces or space in the wrong spot */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, malformed mtime.usec", 0);
libssh2_channel_free(channel);
return NULL;
}
/* Ignore mtime.usec */
s++;
p = (unsigned char *)strchr((const char *)s, ' ');
if (!p || ((p - s) <= 0)) {
/* No spaces or space in the wrong spot */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, too short or malformed", 0);
libssh2_channel_free(channel);
return NULL;
}
*(p++) = '\0';
/* Make sure we don't get fooled by leftover values */
errno = 0;
atime = strtol((const char *)s, NULL, 10);
if (errno) {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, invalid atime", 0);
libssh2_channel_free(channel);
return NULL;
}
/* SCP ACK */
response[0] = '\0';
if (libssh2_channel_write(channel, response, 1) != 1) {
libssh2_channel_free(channel);
return NULL;
}
#ifdef LIBSSH2_DEBUG_SCP
_libssh2_debug(session, LIBSSH2_DBG_SCP, "mtime = %ld, atime = %ld", mtime, atime);
#endif
/* We *should* check that atime.usec is valid, but why let that stop use? */
break;
}
response_len = 0;
while (response_len < LIBSSH2_SCP_RESPONSE_BUFLEN) {
char *s, *p, *e = NULL;
if (libssh2_channel_read(channel, response + response_len, 1) <= 0) {
/* Timeout, give up */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Timed out waiting for SCP response", 0);
libssh2_channel_free(channel);
return NULL;
}
response_len++;
if (response[0] != 'C') {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server", 0);
libssh2_channel_free(channel);
return NULL;
}
if ((response_len > 1) &&
(response[response_len-1] != '\r') &&
(response[response_len-1] != '\n') &&
((response[response_len-1] < 32) || (response[response_len-1] > 126))) {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid data in SCP response", 0);
libssh2_channel_free(channel);
return NULL;
}
if ((response_len < 7) || (response[response_len-1] != '\n')) {
if (response_len == LIBSSH2_SCP_RESPONSE_BUFLEN) {
/* You had your chance */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Unterminated response from SCP server", 0);
libssh2_channel_free(channel);
return NULL;
}
/* Way too short to be an SCP response, or not done yet, short circuit */
continue;
}
/* We're guaranteed not to go under response_len == 0 by the logic above */
while ((response[response_len-1] == '\r') || (response[response_len-1] == '\n')) response_len--;
response[response_len] = '\0';
if (response_len < 6) {
/* EOL came too soon */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, too short", 0);
libssh2_channel_free(channel);
return NULL;
}
s = (char *)(response + 1);
p = strchr(s, ' ');
if (!p || ((p - s) <= 0)) {
/* No spaces or space in the wrong spot */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, malformed mode", 0);
libssh2_channel_free(channel);
return NULL;
}
*(p++) = '\0';
/* Make sure we don't get fooled by leftover values */
errno = 0;
mode = strtol(s, &e, 8);
if ((e && *e) || errno) {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, invalid mode", 0);
libssh2_channel_free(channel);
return NULL;
}
s = strchr(p, ' ');
if (!s || ((s - p) <= 0)) {
/* No spaces or space in the wrong spot */
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, too short or malformed", 0);
libssh2_channel_free(channel);
return NULL;
}
*(s++) = '\0';
/* Make sure we don't get fooled by leftover values */
errno = 0;
size = strtol(p, &e, 10);
if ((e && *e) || errno) {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid response from SCP server, invalid size", 0);
libssh2_channel_free(channel);
return NULL;
}
/* SCP ACK */
response[0] = '\0';
if (libssh2_channel_write(channel, response, 1) != 1) {
libssh2_channel_free(channel);
return NULL;
}
#ifdef LIBSSH2_DEBUG_SCP
_libssh2_debug(session, LIBSSH2_DBG_SCP, "mod = 0%lo size = %ld", mode, size);
#endif
/* We *should* check that basename is valid, but why let that stop us? */
break;
}
if (sb) {
memset(sb, 0, sizeof(struct stat));
sb->st_mtime = mtime;
sb->st_atime = atime;
sb->st_size = size;
sb->st_mode = mode;
}
/* Revert to non-blocking and let the data BEGIN! */
libssh2_channel_set_blocking(channel, 0);
return channel;
}
/* }}} */
/* {{{ libssh2_scp_send_ex
* Send a file using SCP
*/
LIBSSH2_API LIBSSH2_CHANNEL *libssh2_scp_send_ex(LIBSSH2_SESSION *session, const char *path, int mode, size_t size, long mtime, long atime)
{
int path_len = strlen(path);
unsigned char *command, response[LIBSSH2_SCP_RESPONSE_BUFLEN];
unsigned long response_len, command_len = path_len + sizeof("scp -t ");
unsigned const char *base;
LIBSSH2_CHANNEL *channel;
if (mtime || atime) {
command_len++;
}
command = LIBSSH2_ALLOC(session, command_len);
if (!command) {
libssh2_error(session, LIBSSH2_ERROR_ALLOC, "Unable to allocate a command buffer for scp session", 0);
return NULL;
}
if (mtime || atime) {
memcpy(command, "scp -pt ", sizeof("scp -pt ") - 1);
memcpy(command + sizeof("scp -pt ") - 1, path, path_len);
} else {
memcpy(command, "scp -t ", sizeof("scp -t ") - 1);
memcpy(command + sizeof("scp -t ") - 1, path, path_len);
}
command[command_len - 1] = '\0';
#ifdef LIBSSH2_DEBUG_SCP
_libssh2_debug(session, LIBSSH2_DBG_SCP, "Opening channel for SCP send");
#endif
/* Allocate a channel */
if ((channel = libssh2_channel_open_session(session)) == NULL) {
/* previous call set libssh2_session_last_error(), pass it through */
LIBSSH2_FREE(session, command);
return NULL;
}
/* Use blocking I/O for negotiation phase */
libssh2_channel_set_blocking(channel, 1);
/* Request SCP for the desired file */
if (libssh2_channel_process_startup(channel, "exec", sizeof("exec") - 1, (const char *)command, command_len)) {
/* previous call set libssh2_session_last_error(), pass it through */
LIBSSH2_FREE(session, command);
libssh2_channel_free(channel);
return NULL;
}
LIBSSH2_FREE(session, command);
/* Wait for ACK */
if ((libssh2_channel_read(channel, response, 1) <= 0) || (response[0] != 0)) {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid ACK response from remote", 0);
libssh2_channel_free(channel);
return NULL;
}
/* Send mtime and atime to be used for file */
if (mtime || atime) {
response_len = snprintf((char *)response, LIBSSH2_SCP_RESPONSE_BUFLEN, "T%ld 0 %ld 0\n", mtime, atime);
#ifdef LIBSSH2_DEBUG_SCP
_libssh2_debug(session, LIBSSH2_DBG_SCP, "Sent %s", response);
#endif
if (libssh2_channel_write(channel, response, response_len) != response_len) {
libssh2_error(session, LIBSSH2_ERROR_SOCKET_SEND, "Unable to send time data for SCP file", 0);
libssh2_channel_free(channel);
return NULL;
}
/* Wait for ACK */
if ((libssh2_channel_read(channel, response, 1) <= 0) || (response[0] != 0)) {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid ACK response from remote", 0);
libssh2_channel_free(channel);
return NULL;
}
}
/* Send mode, size, and basename */
base = (unsigned char *)strrchr(path, '/');
if (base) {
base++;
} else {
base = (unsigned char *)path;
}
response_len = snprintf((char *)response, LIBSSH2_SCP_RESPONSE_BUFLEN, "C0%o %lu %s\n", mode, (unsigned long)size, base);
#ifdef LIBSSH2_DEBUG_SCP
_libssh2_debug(session, LIBSSH2_DBG_SCP, "Sent %s", response);
#endif
if (libssh2_channel_write(channel, response, response_len) != response_len) {
libssh2_error(session, LIBSSH2_ERROR_SOCKET_SEND, "Unable to send core file data for SCP file", 0);
libssh2_channel_free(channel);
return NULL;
}
/* Wait for ACK */
if ((libssh2_channel_read(channel, response, 1) <= 0) || (response[0] != 0)) {
libssh2_error(session, LIBSSH2_ERROR_SCP_PROTOCOL, "Invalid ACK response from remote", 0);
libssh2_channel_free(channel);
return NULL;
}
/* Ready to start, switch to non-blocking and let calling app send file */
libssh2_channel_set_blocking(channel, 0);
return channel;
}
/* }}} */