1 /*
2 * Copyright (c) 2000-2004 Markus Friedl. All rights reserved.
3 *
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16
17 /* $OpenBSD: sftp-server.c,v 1.71 2007/01/03 07:22:36 stevesk Exp $ */
18
19 #include "includes.h"
20
21 #include <sys/types.h>
22 #include <sys/param.h>
23 #include <sys/stat.h>
24 #ifdef HAVE_SYS_TIME_H
25 # include <sys/time.h>
26 #endif
27
28 #include <dirent.h>
29 #include <errno.h>
30 #include <fcntl.h>
31 #include <pwd.h>
32 #include <stdlib.h>
33 #include <stdio.h>
34 #include <string.h>
35 #include <pwd.h>
36 #include <time.h>
37 #include <unistd.h>
38 #include <stdarg.h>
39
40 #include "xmalloc.h"
41 #include "buffer.h"
42 #include "bufaux.h"
43 #include "log.h"
44 #include "misc.h"
45 #include "uidswap.h"
46
47 #include "sftp.h"
48 #include "sftp-common.h"
49
50 #ifdef HAVE___PROGNAME
51 extern char *__progname;
52 #else
53 char *__progname;
54 #endif
55
56 /* helper */
57 #define get_int64() buffer_get_int64(&iqueue);
58 #define get_int() buffer_get_int(&iqueue);
59 #define get_string(lenp) buffer_get_string(&iqueue, lenp);
60
61 void cleanup_exit(int i);
62
63 /* Our verbosity */
64 LogLevel log_level = SYSLOG_LEVEL_ERROR;
65
66 /* Our client */
67 struct passwd *pw = NULL;
68 char *client_addr = NULL;
69
70 /* input and output queue */
71 Buffer iqueue;
72 Buffer oqueue;
73
74 /* Version of client */
75 int version;
76
77 /* portable attributes, etc. */
78
79 typedef struct Stat Stat;
80
81 struct Stat {
82 char *name;
83 char *long_name;
84 Attrib attrib;
85 };
86
87 static int
errno_to_portable(int unixerrno)88 errno_to_portable(int unixerrno)
89 {
90 int ret = 0;
91
92 switch (unixerrno) {
93 case 0:
94 ret = SSH2_FX_OK;
95 break;
96 case ENOENT:
97 case ENOTDIR:
98 case EBADF:
99 case ELOOP:
100 ret = SSH2_FX_NO_SUCH_FILE;
101 break;
102 case EPERM:
103 case EACCES:
104 case EFAULT:
105 ret = SSH2_FX_PERMISSION_DENIED;
106 break;
107 case ENAMETOOLONG:
108 case EINVAL:
109 ret = SSH2_FX_BAD_MESSAGE;
110 break;
111 default:
112 ret = SSH2_FX_FAILURE;
113 break;
114 }
115 return ret;
116 }
117
118 static int
flags_from_portable(int pflags)119 flags_from_portable(int pflags)
120 {
121 int flags = 0;
122
123 if ((pflags & SSH2_FXF_READ) &&
124 (pflags & SSH2_FXF_WRITE)) {
125 flags = O_RDWR;
126 } else if (pflags & SSH2_FXF_READ) {
127 flags = O_RDONLY;
128 } else if (pflags & SSH2_FXF_WRITE) {
129 flags = O_WRONLY;
130 }
131 if (pflags & SSH2_FXF_CREAT)
132 flags |= O_CREAT;
133 if (pflags & SSH2_FXF_TRUNC)
134 flags |= O_TRUNC;
135 if (pflags & SSH2_FXF_EXCL)
136 flags |= O_EXCL;
137 return flags;
138 }
139
140 static const char *
string_from_portable(int pflags)141 string_from_portable(int pflags)
142 {
143 static char ret[128];
144
145 *ret = '\0';
146
147 #define PAPPEND(str) { \
148 if (*ret != '\0') \
149 strlcat(ret, ",", sizeof(ret)); \
150 strlcat(ret, str, sizeof(ret)); \
151 }
152
153 if (pflags & SSH2_FXF_READ)
154 PAPPEND("READ")
155 if (pflags & SSH2_FXF_WRITE)
156 PAPPEND("WRITE")
157 if (pflags & SSH2_FXF_CREAT)
158 PAPPEND("CREATE")
159 if (pflags & SSH2_FXF_TRUNC)
160 PAPPEND("TRUNCATE")
161 if (pflags & SSH2_FXF_EXCL)
162 PAPPEND("EXCL")
163
164 return ret;
165 }
166
167 static Attrib *
get_attrib(void)168 get_attrib(void)
169 {
170 return decode_attrib(&iqueue);
171 }
172
173 /* handle handles */
174
175 typedef struct Handle Handle;
176 struct Handle {
177 int use;
178 DIR *dirp;
179 int fd;
180 char *name;
181 u_int64_t bytes_read, bytes_write;
182 };
183
184 enum {
185 HANDLE_UNUSED,
186 HANDLE_DIR,
187 HANDLE_FILE
188 };
189
190 Handle handles[100];
191
192 static void
handle_init(void)193 handle_init(void)
194 {
195 u_int i;
196
197 for (i = 0; i < sizeof(handles)/sizeof(Handle); i++)
198 handles[i].use = HANDLE_UNUSED;
199 }
200
201 static int
handle_new(int use,const char * name,int fd,DIR * dirp)202 handle_new(int use, const char *name, int fd, DIR *dirp)
203 {
204 u_int i;
205
206 for (i = 0; i < sizeof(handles)/sizeof(Handle); i++) {
207 if (handles[i].use == HANDLE_UNUSED) {
208 handles[i].use = use;
209 handles[i].dirp = dirp;
210 handles[i].fd = fd;
211 handles[i].name = xstrdup(name);
212 handles[i].bytes_read = handles[i].bytes_write = 0;
213 return i;
214 }
215 }
216 return -1;
217 }
218
219 static int
handle_is_ok(int i,int type)220 handle_is_ok(int i, int type)
221 {
222 return i >= 0 && (u_int)i < sizeof(handles)/sizeof(Handle) &&
223 handles[i].use == type;
224 }
225
226 static int
handle_to_string(int handle,char ** stringp,int * hlenp)227 handle_to_string(int handle, char **stringp, int *hlenp)
228 {
229 if (stringp == NULL || hlenp == NULL)
230 return -1;
231 *stringp = xmalloc(sizeof(int32_t));
232 put_u32(*stringp, handle);
233 *hlenp = sizeof(int32_t);
234 return 0;
235 }
236
237 static int
handle_from_string(const char * handle,u_int hlen)238 handle_from_string(const char *handle, u_int hlen)
239 {
240 int val;
241
242 if (hlen != sizeof(int32_t))
243 return -1;
244 val = get_u32(handle);
245 if (handle_is_ok(val, HANDLE_FILE) ||
246 handle_is_ok(val, HANDLE_DIR))
247 return val;
248 return -1;
249 }
250
251 static char *
handle_to_name(int handle)252 handle_to_name(int handle)
253 {
254 if (handle_is_ok(handle, HANDLE_DIR)||
255 handle_is_ok(handle, HANDLE_FILE))
256 return handles[handle].name;
257 return NULL;
258 }
259
260 static DIR *
handle_to_dir(int handle)261 handle_to_dir(int handle)
262 {
263 if (handle_is_ok(handle, HANDLE_DIR))
264 return handles[handle].dirp;
265 return NULL;
266 }
267
268 static int
handle_to_fd(int handle)269 handle_to_fd(int handle)
270 {
271 if (handle_is_ok(handle, HANDLE_FILE))
272 return handles[handle].fd;
273 return -1;
274 }
275
276 static void
handle_update_read(int handle,ssize_t bytes)277 handle_update_read(int handle, ssize_t bytes)
278 {
279 if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0)
280 handles[handle].bytes_read += bytes;
281 }
282
283 static void
handle_update_write(int handle,ssize_t bytes)284 handle_update_write(int handle, ssize_t bytes)
285 {
286 if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0)
287 handles[handle].bytes_write += bytes;
288 }
289
290 static u_int64_t
handle_bytes_read(int handle)291 handle_bytes_read(int handle)
292 {
293 if (handle_is_ok(handle, HANDLE_FILE))
294 return (handles[handle].bytes_read);
295 return 0;
296 }
297
298 static u_int64_t
handle_bytes_write(int handle)299 handle_bytes_write(int handle)
300 {
301 if (handle_is_ok(handle, HANDLE_FILE))
302 return (handles[handle].bytes_write);
303 return 0;
304 }
305
306 static int
handle_close(int handle)307 handle_close(int handle)
308 {
309 int ret = -1;
310
311 if (handle_is_ok(handle, HANDLE_FILE)) {
312 ret = close(handles[handle].fd);
313 handles[handle].use = HANDLE_UNUSED;
314 xfree(handles[handle].name);
315 } else if (handle_is_ok(handle, HANDLE_DIR)) {
316 ret = closedir(handles[handle].dirp);
317 handles[handle].use = HANDLE_UNUSED;
318 xfree(handles[handle].name);
319 } else {
320 errno = ENOENT;
321 }
322 return ret;
323 }
324
325 static void
handle_log_close(int handle,char * emsg)326 handle_log_close(int handle, char *emsg)
327 {
328 if (handle_is_ok(handle, HANDLE_FILE)) {
329 log("%s%sclose \"%s\" bytes read %llu written %llu",
330 emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ",
331 handle_to_name(handle),
332 (unsigned long long)handle_bytes_read(handle),
333 (unsigned long long)handle_bytes_write(handle));
334 } else {
335 log("%s%sclosedir \"%s\"",
336 emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ",
337 handle_to_name(handle));
338 }
339 }
340
341 static void
handle_log_exit(void)342 handle_log_exit(void)
343 {
344 u_int i;
345
346 for (i = 0; i < sizeof(handles)/sizeof(Handle); i++)
347 if (handles[i].use != HANDLE_UNUSED)
348 handle_log_close(i, "forced");
349 }
350
351 static int
get_handle(void)352 get_handle(void)
353 {
354 char *handle;
355 int val = -1;
356 u_int hlen;
357
358 handle = get_string(&hlen);
359 if (hlen < 256)
360 val = handle_from_string(handle, hlen);
361 xfree(handle);
362 return val;
363 }
364
365 /* send replies */
366
367 static void
send_msg(Buffer * m)368 send_msg(Buffer *m)
369 {
370 int mlen = buffer_len(m);
371
372 buffer_put_int(&oqueue, mlen);
373 buffer_append(&oqueue, buffer_ptr(m), mlen);
374 buffer_consume(m, mlen);
375 }
376
377 static const char *
status_to_message(u_int32_t status)378 status_to_message(u_int32_t status)
379 {
380 const char *status_messages[] = {
381 "Success", /* SSH_FX_OK */
382 "End of file", /* SSH_FX_EOF */
383 "No such file", /* SSH_FX_NO_SUCH_FILE */
384 "Permission denied", /* SSH_FX_PERMISSION_DENIED */
385 "Failure", /* SSH_FX_FAILURE */
386 "Bad message", /* SSH_FX_BAD_MESSAGE */
387 "No connection", /* SSH_FX_NO_CONNECTION */
388 "Connection lost", /* SSH_FX_CONNECTION_LOST */
389 "Operation unsupported", /* SSH_FX_OP_UNSUPPORTED */
390 "Unknown error" /* Others */
391 };
392 return (status_messages[MIN(status,SSH2_FX_MAX)]);
393 }
394
395 static void
send_status(u_int32_t id,u_int32_t status)396 send_status(u_int32_t id, u_int32_t status)
397 {
398 Buffer msg;
399
400 debug3("request %u: sent status %u", id, status);
401 if (log_level > SYSLOG_LEVEL_VERBOSE ||
402 (status != SSH2_FX_OK && status != SSH2_FX_EOF))
403 log("sent status %s", status_to_message(status));
404 buffer_init(&msg);
405 buffer_put_char(&msg, SSH2_FXP_STATUS);
406 buffer_put_int(&msg, id);
407 buffer_put_int(&msg, status);
408 if (version >= 3) {
409 buffer_put_cstring(&msg, status_to_message(status));
410 buffer_put_cstring(&msg, "");
411 }
412 send_msg(&msg);
413 buffer_free(&msg);
414 }
415 static void
send_data_or_handle(char type,u_int32_t id,const char * data,int dlen)416 send_data_or_handle(char type, u_int32_t id, const char *data, int dlen)
417 {
418 Buffer msg;
419
420 buffer_init(&msg);
421 buffer_put_char(&msg, type);
422 buffer_put_int(&msg, id);
423 buffer_put_string(&msg, data, dlen);
424 send_msg(&msg);
425 buffer_free(&msg);
426 }
427
428 static void
send_data(u_int32_t id,const char * data,int dlen)429 send_data(u_int32_t id, const char *data, int dlen)
430 {
431 debug("request %u: sent data len %d", id, dlen);
432 send_data_or_handle(SSH2_FXP_DATA, id, data, dlen);
433 }
434
435 static void
send_handle(u_int32_t id,int handle)436 send_handle(u_int32_t id, int handle)
437 {
438 char *string;
439 int hlen;
440
441 handle_to_string(handle, &string, &hlen);
442 debug("request %u: sent handle handle %d", id, handle);
443 send_data_or_handle(SSH2_FXP_HANDLE, id, string, hlen);
444 xfree(string);
445 }
446
447 static void
send_names(u_int32_t id,int count,const Stat * stats)448 send_names(u_int32_t id, int count, const Stat *stats)
449 {
450 Buffer msg;
451 int i;
452
453 buffer_init(&msg);
454 buffer_put_char(&msg, SSH2_FXP_NAME);
455 buffer_put_int(&msg, id);
456 buffer_put_int(&msg, count);
457 debug("request %u: sent names count %d", id, count);
458 for (i = 0; i < count; i++) {
459 buffer_put_cstring(&msg, stats[i].name);
460 buffer_put_cstring(&msg, stats[i].long_name);
461 encode_attrib(&msg, &stats[i].attrib);
462 }
463 send_msg(&msg);
464 buffer_free(&msg);
465 }
466
467 static void
send_attrib(u_int32_t id,const Attrib * a)468 send_attrib(u_int32_t id, const Attrib *a)
469 {
470 Buffer msg;
471
472 debug("request %u: sent attrib have 0x%x", id, a->flags);
473 buffer_init(&msg);
474 buffer_put_char(&msg, SSH2_FXP_ATTRS);
475 buffer_put_int(&msg, id);
476 encode_attrib(&msg, a);
477 send_msg(&msg);
478 buffer_free(&msg);
479 }
480
481 /* parse incoming */
482
483 static void
process_init(void)484 process_init(void)
485 {
486 Buffer msg;
487
488 version = get_int();
489 verbose("received client version %d", version);
490 buffer_init(&msg);
491 buffer_put_char(&msg, SSH2_FXP_VERSION);
492 buffer_put_int(&msg, SSH2_FILEXFER_VERSION);
493 send_msg(&msg);
494 buffer_free(&msg);
495 }
496
497 static void
process_open(void)498 process_open(void)
499 {
500 u_int32_t id, pflags;
501 Attrib *a;
502 char *name;
503 int handle, fd, flags, mode, status = SSH2_FX_FAILURE;
504
505 id = get_int();
506 name = get_string(NULL);
507 pflags = get_int(); /* portable flags */
508 debug3("request %u: open flags %d", id, pflags);
509 a = get_attrib();
510 flags = flags_from_portable(pflags);
511 mode = (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ? a->perm : 0666;
512 log("open \"%s\" flags %s mode 0%o",
513 name, string_from_portable(pflags), mode);
514 fd = open(name, flags, mode);
515 if (fd < 0) {
516 status = errno_to_portable(errno);
517 } else {
518 handle = handle_new(HANDLE_FILE, name, fd, NULL);
519 if (handle < 0) {
520 close(fd);
521 } else {
522 send_handle(id, handle);
523 status = SSH2_FX_OK;
524 }
525 }
526 if (status != SSH2_FX_OK)
527 send_status(id, status);
528 xfree(name);
529 }
530
531 static void
process_close(void)532 process_close(void)
533 {
534 u_int32_t id;
535 int handle, ret, status = SSH2_FX_FAILURE;
536
537 id = get_int();
538 handle = get_handle();
539 debug3("request %u: close handle %u", id, handle);
540 handle_log_close(handle, NULL);
541 ret = handle_close(handle);
542 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
543 send_status(id, status);
544 }
545
546 static void
process_read(void)547 process_read(void)
548 {
549 char buf[64*1024];
550 u_int32_t id, len;
551 int handle, fd, ret, status = SSH2_FX_FAILURE;
552 u_int64_t off;
553
554 id = get_int();
555 handle = get_handle();
556 off = get_int64();
557 len = get_int();
558
559 debug("request %u: read \"%s\" (handle %d) off %llu len %d",
560 id, handle_to_name(handle), handle, (unsigned long long)off, len);
561 if (len > sizeof buf) {
562 len = sizeof buf;
563 debug2("read change len %d", len);
564 }
565 fd = handle_to_fd(handle);
566 if (fd >= 0) {
567 if (lseek(fd, off, SEEK_SET) < 0) {
568 error("process_read: seek failed");
569 status = errno_to_portable(errno);
570 } else {
571 ret = read(fd, buf, len);
572 if (ret < 0) {
573 status = errno_to_portable(errno);
574 } else if (ret == 0) {
575 status = SSH2_FX_EOF;
576 } else {
577 send_data(id, buf, ret);
578 status = SSH2_FX_OK;
579 handle_update_read(handle, ret);
580 }
581 }
582 }
583 if (status != SSH2_FX_OK)
584 send_status(id, status);
585 }
586
587 static void
process_write(void)588 process_write(void)
589 {
590 u_int32_t id;
591 u_int64_t off;
592 u_int len;
593 int handle, fd, ret, status = SSH2_FX_FAILURE;
594 char *data;
595
596 id = get_int();
597 handle = get_handle();
598 off = get_int64();
599 data = get_string(&len);
600
601 debug("request %u: write \"%s\" (handle %d) off %llu len %d",
602 id, handle_to_name(handle), handle, (unsigned long long)off, len);
603 fd = handle_to_fd(handle);
604 if (fd >= 0) {
605 if (lseek(fd, off, SEEK_SET) < 0) {
606 status = errno_to_portable(errno);
607 error("process_write: seek failed");
608 } else {
609 /* XXX ATOMICIO ? */
610 ret = write(fd, data, len);
611 if (ret < 0) {
612 error("process_write: write failed");
613 status = errno_to_portable(errno);
614 } else if ((size_t)ret == len) {
615 status = SSH2_FX_OK;
616 handle_update_write(handle, ret);
617 } else {
618 debug2("nothing at all written");
619 }
620 }
621 }
622 send_status(id, status);
623 xfree(data);
624 }
625
626 static void
process_do_stat(int do_lstat)627 process_do_stat(int do_lstat)
628 {
629 Attrib a;
630 struct stat st;
631 u_int32_t id;
632 char *name;
633 int ret, status = SSH2_FX_FAILURE;
634
635 id = get_int();
636 name = get_string(NULL);
637 debug3("request %u: %sstat", id, do_lstat ? "l" : "");
638 verbose("%sstat name \"%s\"", do_lstat ? "l" : "", name);
639 ret = do_lstat ? lstat(name, &st) : stat(name, &st);
640 if (ret < 0) {
641 status = errno_to_portable(errno);
642 } else {
643 stat_to_attrib(&st, &a);
644 send_attrib(id, &a);
645 status = SSH2_FX_OK;
646 }
647 if (status != SSH2_FX_OK)
648 send_status(id, status);
649 xfree(name);
650 }
651
652 static void
process_stat(void)653 process_stat(void)
654 {
655 process_do_stat(0);
656 }
657
658 static void
process_lstat(void)659 process_lstat(void)
660 {
661 process_do_stat(1);
662 }
663
664 static void
process_fstat(void)665 process_fstat(void)
666 {
667 Attrib a;
668 struct stat st;
669 u_int32_t id;
670 int fd, ret, handle, status = SSH2_FX_FAILURE;
671
672 id = get_int();
673 handle = get_handle();
674 debug("request %u: fstat \"%s\" (handle %u)",
675 id, handle_to_name(handle), handle);
676 fd = handle_to_fd(handle);
677 if (fd >= 0) {
678 ret = fstat(fd, &st);
679 if (ret < 0) {
680 status = errno_to_portable(errno);
681 } else {
682 stat_to_attrib(&st, &a);
683 send_attrib(id, &a);
684 status = SSH2_FX_OK;
685 }
686 }
687 if (status != SSH2_FX_OK)
688 send_status(id, status);
689 }
690
691 static struct timeval *
attrib_to_tv(const Attrib * a)692 attrib_to_tv(const Attrib *a)
693 {
694 static struct timeval tv[2];
695
696 tv[0].tv_sec = a->atime;
697 tv[0].tv_usec = 0;
698 tv[1].tv_sec = a->mtime;
699 tv[1].tv_usec = 0;
700 return tv;
701 }
702
703 static void
process_setstat(void)704 process_setstat(void)
705 {
706 Attrib *a;
707 u_int32_t id;
708 char *name;
709 int status = SSH2_FX_OK, ret;
710
711 id = get_int();
712 name = get_string(NULL);
713 a = get_attrib();
714 debug("request %u: setstat name \"%s\"", id, name);
715 if (a->flags & SSH2_FILEXFER_ATTR_SIZE) {
716 log("set \"%s\" size %llu",
717 name, (unsigned long long)a->size);
718 ret = truncate(name, a->size);
719 if (ret == -1)
720 status = errno_to_portable(errno);
721 }
722 if (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) {
723 log("set \"%s\" mode %04o", name, a->perm);
724 ret = chmod(name, a->perm & 07777);
725 if (ret == -1)
726 status = errno_to_portable(errno);
727 }
728 if (a->flags & SSH2_FILEXFER_ATTR_ACMODTIME) {
729 char buf[64];
730 time_t t = a->mtime;
731
732 strftime(buf, sizeof(buf), "%Y" "%m%d-%H:%M:%S",
733 localtime(&t));
734 log("set \"%s\" modtime %s", name, buf);
735 ret = utimes(name, attrib_to_tv(a));
736 if (ret == -1)
737 status = errno_to_portable(errno);
738 }
739 if (a->flags & SSH2_FILEXFER_ATTR_UIDGID) {
740 log("set \"%s\" owner %lu group %lu", name,
741 (u_long)a->uid, (u_long)a->gid);
742 ret = chown(name, a->uid, a->gid);
743 if (ret == -1)
744 status = errno_to_portable(errno);
745 }
746 send_status(id, status);
747 xfree(name);
748 }
749
750 static void
process_fsetstat(void)751 process_fsetstat(void)
752 {
753 Attrib *a;
754 u_int32_t id;
755 int handle, fd, ret;
756 int status = SSH2_FX_OK;
757
758 id = get_int();
759 handle = get_handle();
760 a = get_attrib();
761 debug("request %u: fsetstat handle %d", id, handle);
762 fd = handle_to_fd(handle);
763 if (fd < 0) {
764 status = SSH2_FX_FAILURE;
765 } else {
766 char *name = handle_to_name(handle);
767
768 if (a->flags & SSH2_FILEXFER_ATTR_SIZE) {
769 log("set \"%s\" size %llu",
770 name, (unsigned long long)a->size);
771 ret = ftruncate(fd, a->size);
772 if (ret == -1)
773 status = errno_to_portable(errno);
774 }
775 if (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) {
776 log("set \"%s\" mode %04o", name, a->perm);
777 #ifdef HAVE_FCHMOD
778 ret = fchmod(fd, a->perm & 07777);
779 #else
780 ret = chmod(name, a->perm & 07777);
781 #endif
782 if (ret == -1)
783 status = errno_to_portable(errno);
784 }
785 if (a->flags & SSH2_FILEXFER_ATTR_ACMODTIME) {
786 char buf[64];
787 time_t t = a->mtime;
788
789 strftime(buf, sizeof(buf), "%Y" "%m%d-%H:%M:%S",
790 localtime(&t));
791 log("set \"%s\" modtime %s", name, buf);
792 #ifdef HAVE_FUTIMES
793 ret = futimes(fd, attrib_to_tv(a));
794 #else
795 ret = utimes(name, attrib_to_tv(a));
796 #endif
797 if (ret == -1)
798 status = errno_to_portable(errno);
799 }
800 if (a->flags & SSH2_FILEXFER_ATTR_UIDGID) {
801 log("set \"%s\" owner %lu group %lu", name,
802 (u_long)a->uid, (u_long)a->gid);
803 #ifdef HAVE_FCHOWN
804 ret = fchown(fd, a->uid, a->gid);
805 #else
806 ret = chown(name, a->uid, a->gid);
807 #endif
808 if (ret == -1)
809 status = errno_to_portable(errno);
810 }
811 }
812 send_status(id, status);
813 }
814
815 static void
process_opendir(void)816 process_opendir(void)
817 {
818 DIR *dirp = NULL;
819 char *path;
820 int handle, status = SSH2_FX_FAILURE;
821 u_int32_t id;
822
823 id = get_int();
824 path = get_string(NULL);
825 debug3("request %u: opendir", id);
826 log("opendir \"%s\"", path);
827 dirp = opendir(path);
828 if (dirp == NULL) {
829 status = errno_to_portable(errno);
830 } else {
831 handle = handle_new(HANDLE_DIR, path, 0, dirp);
832 if (handle < 0) {
833 closedir(dirp);
834 } else {
835 send_handle(id, handle);
836 status = SSH2_FX_OK;
837 }
838
839 }
840 if (status != SSH2_FX_OK)
841 send_status(id, status);
842 xfree(path);
843 }
844
845 static void
process_readdir(void)846 process_readdir(void)
847 {
848 DIR *dirp;
849 struct dirent *dp;
850 char *path;
851 int handle;
852 u_int32_t id;
853
854 id = get_int();
855 handle = get_handle();
856 debug("request %u: readdir \"%s\" (handle %d)", id,
857 handle_to_name(handle), handle);
858 dirp = handle_to_dir(handle);
859 path = handle_to_name(handle);
860 if (dirp == NULL || path == NULL) {
861 send_status(id, SSH2_FX_FAILURE);
862 } else {
863 struct stat st;
864 char pathname[MAXPATHLEN];
865 Stat *stats;
866 int nstats = 10, count = 0, i;
867
868 stats = xcalloc(nstats, sizeof(Stat));
869 while ((dp = readdir(dirp)) != NULL) {
870 if (count >= nstats) {
871 nstats *= 2;
872 stats = xrealloc(stats, nstats * sizeof(Stat));
873 }
874 /* XXX OVERFLOW ? */
875 snprintf(pathname, sizeof pathname, "%s%s%s", path,
876 strcmp(path, "/") ? "/" : "", dp->d_name);
877 if (lstat(pathname, &st) < 0)
878 continue;
879 stat_to_attrib(&st, &(stats[count].attrib));
880 stats[count].name = xstrdup(dp->d_name);
881 stats[count].long_name = ls_file(dp->d_name, &st, 0);
882 count++;
883 /* send up to 100 entries in one message */
884 /* XXX check packet size instead */
885 if (count == 100)
886 break;
887 }
888 if (count > 0) {
889 send_names(id, count, stats);
890 for (i = 0; i < count; i++) {
891 xfree(stats[i].name);
892 xfree(stats[i].long_name);
893 }
894 } else {
895 send_status(id, SSH2_FX_EOF);
896 }
897 xfree(stats);
898 }
899 }
900
901 static void
process_remove(void)902 process_remove(void)
903 {
904 char *name;
905 u_int32_t id;
906 int status = SSH2_FX_FAILURE;
907 int ret;
908
909 id = get_int();
910 name = get_string(NULL);
911 debug3("request %u: remove", id);
912 log("remove name \"%s\"", name);
913 ret = unlink(name);
914 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
915 send_status(id, status);
916 xfree(name);
917 }
918
919 static void
process_mkdir(void)920 process_mkdir(void)
921 {
922 Attrib *a;
923 u_int32_t id;
924 char *name;
925 int ret, mode, status = SSH2_FX_FAILURE;
926
927 id = get_int();
928 name = get_string(NULL);
929 a = get_attrib();
930 mode = (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ?
931 a->perm & 0777 : 0777;
932 debug3("request %u: mkdir", id);
933 log("mkdir name \"%s\" mode 0%o", name, mode);
934 ret = mkdir(name, mode);
935 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
936 send_status(id, status);
937 xfree(name);
938 }
939
940 static void
process_rmdir(void)941 process_rmdir(void)
942 {
943 u_int32_t id;
944 char *name;
945 int ret, status;
946
947 id = get_int();
948 name = get_string(NULL);
949 debug3("request %u: rmdir", id);
950 log("rmdir name \"%s\"", name);
951 ret = rmdir(name);
952 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
953 send_status(id, status);
954 xfree(name);
955 }
956
957 static void
process_realpath(void)958 process_realpath(void)
959 {
960 char resolvedname[MAXPATHLEN];
961 u_int32_t id;
962 char *path;
963
964 id = get_int();
965 path = get_string(NULL);
966 if (path[0] == '\0') {
967 xfree(path);
968 path = xstrdup(".");
969 }
970 debug3("request %u: realpath", id);
971 verbose("realpath \"%s\"", path);
972 if (realpath(path, resolvedname) == NULL) {
973 send_status(id, errno_to_portable(errno));
974 } else {
975 Stat s;
976 attrib_clear(&s.attrib);
977 s.name = s.long_name = resolvedname;
978 send_names(id, 1, &s);
979 }
980 xfree(path);
981 }
982
983 static void
process_rename(void)984 process_rename(void)
985 {
986 u_int32_t id;
987 char *oldpath, *newpath;
988 int status;
989 struct stat sb;
990
991 id = get_int();
992 oldpath = get_string(NULL);
993 newpath = get_string(NULL);
994 debug3("request %u: rename", id);
995 log("rename old \"%s\" new \"%s\"", oldpath, newpath);
996 status = SSH2_FX_FAILURE;
997 if (lstat(oldpath, &sb) == -1)
998 status = errno_to_portable(errno);
999 else if (S_ISREG(sb.st_mode)) {
1000 /* Race-free rename of regular files */
1001 if (link(oldpath, newpath) == -1) {
1002 if (errno == EOPNOTSUPP
1003 #ifdef LINK_OPNOTSUPP_ERRNO
1004 || errno == LINK_OPNOTSUPP_ERRNO
1005 #endif
1006 ) {
1007 struct stat st;
1008
1009 /*
1010 * fs doesn't support links, so fall back to
1011 * stat+rename. This is racy.
1012 */
1013 if (stat(newpath, &st) == -1) {
1014 if (rename(oldpath, newpath) == -1)
1015 status =
1016 errno_to_portable(errno);
1017 else
1018 status = SSH2_FX_OK;
1019 }
1020 } else {
1021 status = errno_to_portable(errno);
1022 }
1023 } else if (unlink(oldpath) == -1) {
1024 status = errno_to_portable(errno);
1025 /* clean spare link */
1026 unlink(newpath);
1027 } else
1028 status = SSH2_FX_OK;
1029 } else if (stat(newpath, &sb) == -1) {
1030 if (rename(oldpath, newpath) == -1)
1031 status = errno_to_portable(errno);
1032 else
1033 status = SSH2_FX_OK;
1034 }
1035 send_status(id, status);
1036 xfree(oldpath);
1037 xfree(newpath);
1038 }
1039
1040 static void
process_readlink(void)1041 process_readlink(void)
1042 {
1043 u_int32_t id;
1044 int len;
1045 char buf[MAXPATHLEN];
1046 char *path;
1047
1048 id = get_int();
1049 path = get_string(NULL);
1050 debug3("request %u: readlink", id);
1051 verbose("readlink \"%s\"", path);
1052 if ((len = readlink(path, buf, sizeof(buf) - 1)) == -1)
1053 send_status(id, errno_to_portable(errno));
1054 else {
1055 Stat s;
1056
1057 buf[len] = '\0';
1058 attrib_clear(&s.attrib);
1059 s.name = s.long_name = buf;
1060 send_names(id, 1, &s);
1061 }
1062 xfree(path);
1063 }
1064
1065 static void
process_symlink(void)1066 process_symlink(void)
1067 {
1068 u_int32_t id;
1069 char *oldpath, *newpath;
1070 int ret, status;
1071
1072 id = get_int();
1073 oldpath = get_string(NULL);
1074 newpath = get_string(NULL);
1075 debug3("request %u: symlink", id);
1076 log("symlink old \"%s\" new \"%s\"", oldpath, newpath);
1077 /* this will fail if 'newpath' exists */
1078 ret = symlink(oldpath, newpath);
1079 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
1080 send_status(id, status);
1081 xfree(oldpath);
1082 xfree(newpath);
1083 }
1084
1085 static void
process_extended(void)1086 process_extended(void)
1087 {
1088 u_int32_t id;
1089 char *request;
1090
1091 id = get_int();
1092 request = get_string(NULL);
1093 send_status(id, SSH2_FX_OP_UNSUPPORTED); /* MUST */
1094 xfree(request);
1095 }
1096
1097 /* stolen from ssh-agent */
1098
1099 static void
process(void)1100 process(void)
1101 {
1102 u_int msg_len;
1103 u_int buf_len;
1104 u_int consumed;
1105 u_int type;
1106 u_char *cp;
1107
1108 buf_len = buffer_len(&iqueue);
1109 if (buf_len < 5)
1110 return; /* Incomplete message. */
1111 cp = buffer_ptr(&iqueue);
1112 msg_len = get_u32(cp);
1113 if (msg_len > SFTP_MAX_MSG_LENGTH) {
1114 error("bad message from %s local user %s",
1115 client_addr, pw->pw_name);
1116 cleanup_exit(11);
1117 }
1118 if (buf_len < msg_len + 4)
1119 return;
1120 buffer_consume(&iqueue, 4);
1121 buf_len -= 4;
1122 type = buffer_get_char(&iqueue);
1123 switch (type) {
1124 case SSH2_FXP_INIT:
1125 process_init();
1126 break;
1127 case SSH2_FXP_OPEN:
1128 process_open();
1129 break;
1130 case SSH2_FXP_CLOSE:
1131 process_close();
1132 break;
1133 case SSH2_FXP_READ:
1134 process_read();
1135 break;
1136 case SSH2_FXP_WRITE:
1137 process_write();
1138 break;
1139 case SSH2_FXP_LSTAT:
1140 process_lstat();
1141 break;
1142 case SSH2_FXP_FSTAT:
1143 process_fstat();
1144 break;
1145 case SSH2_FXP_SETSTAT:
1146 process_setstat();
1147 break;
1148 case SSH2_FXP_FSETSTAT:
1149 process_fsetstat();
1150 break;
1151 case SSH2_FXP_OPENDIR:
1152 process_opendir();
1153 break;
1154 case SSH2_FXP_READDIR:
1155 process_readdir();
1156 break;
1157 case SSH2_FXP_REMOVE:
1158 process_remove();
1159 break;
1160 case SSH2_FXP_MKDIR:
1161 process_mkdir();
1162 break;
1163 case SSH2_FXP_RMDIR:
1164 process_rmdir();
1165 break;
1166 case SSH2_FXP_REALPATH:
1167 process_realpath();
1168 break;
1169 case SSH2_FXP_STAT:
1170 process_stat();
1171 break;
1172 case SSH2_FXP_RENAME:
1173 process_rename();
1174 break;
1175 case SSH2_FXP_READLINK:
1176 process_readlink();
1177 break;
1178 case SSH2_FXP_SYMLINK:
1179 process_symlink();
1180 break;
1181 case SSH2_FXP_EXTENDED:
1182 process_extended();
1183 break;
1184 default:
1185 error("Unknown message %d", type);
1186 break;
1187 }
1188 /* discard the remaining bytes from the current packet */
1189 if (buf_len < buffer_len(&iqueue))
1190 fatal("iqueue grew unexpectedly");
1191 consumed = buf_len - buffer_len(&iqueue);
1192 if (msg_len < consumed)
1193 fatal("msg_len %d < consumed %d", msg_len, consumed);
1194 if (msg_len > consumed)
1195 buffer_consume(&iqueue, msg_len - consumed);
1196 }
1197
1198 /*
1199 * Cleanup handler that logs active handles upon normal exit. Not static since
1200 * sftp-server-main.c file needs that as well.
1201 */
1202 void
cleanup_exit(int i)1203 cleanup_exit(int i)
1204 {
1205 if (pw != NULL && client_addr != NULL) {
1206 handle_log_exit();
1207 log("session closed for local user %s from [%s]",
1208 pw->pw_name, client_addr);
1209 }
1210 _exit(i);
1211 }
1212
1213 static void
usage(void)1214 usage(void)
1215 {
1216 fprintf(stderr,
1217 "Usage: %s [-he] [-l log_level] [-f log_facility]\n", __progname);
1218 exit(1);
1219 }
1220
1221 int
sftp_server_main(int argc,char ** argv,struct passwd * user_pw)1222 sftp_server_main(int argc, char **argv, struct passwd *user_pw)
1223 {
1224 fd_set *rset, *wset;
1225 int in, out, max, ch, skipargs = 0, log_stderr = 0;
1226 ssize_t len, olen, set_size;
1227 SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
1228 char *cp, buf[4*4096];
1229
1230 extern char *optarg;
1231
1232 __progname = get_progname(argv[0]);
1233
1234 (void) g11n_setlocale(LC_ALL, "");
1235
1236 log_init(__progname, log_level, log_facility, log_stderr);
1237
1238 while (!skipargs && (ch = getopt(argc, argv, "C:f:l:che")) != -1) {
1239 switch (ch) {
1240 case 'c':
1241 /*
1242 * Ignore all arguments if we are invoked as a
1243 * shell using "sftp-server -c command"
1244 */
1245 skipargs = 1;
1246 break;
1247 case 'e':
1248 log_stderr = 1;
1249 break;
1250 case 'l':
1251 log_level = log_level_number(optarg);
1252 if (log_level == SYSLOG_LEVEL_NOT_SET)
1253 error("Invalid log level \"%s\"", optarg);
1254 break;
1255 case 'f':
1256 log_facility = log_facility_number(optarg);
1257 if (log_facility == SYSLOG_FACILITY_NOT_SET)
1258 error("Invalid log facility \"%s\"", optarg);
1259 break;
1260 case 'h':
1261 default:
1262 usage();
1263 }
1264 }
1265
1266 log_init(__progname, log_level, log_facility, log_stderr);
1267
1268 if ((cp = getenv("SSH_CONNECTION")) != NULL) {
1269 client_addr = xstrdup(cp);
1270 if ((cp = strchr(client_addr, ' ')) == NULL)
1271 fatal("Malformed SSH_CONNECTION variable: \"%s\"",
1272 getenv("SSH_CONNECTION"));
1273 *cp = '\0';
1274 } else
1275 client_addr = xstrdup("UNKNOWN");
1276
1277 pw = pwcopy(user_pw);
1278
1279 log("session opened for local user %s from [%s]",
1280 pw->pw_name, client_addr);
1281
1282 handle_init();
1283
1284 in = dup(STDIN_FILENO);
1285 out = dup(STDOUT_FILENO);
1286
1287 #ifdef HAVE_CYGWIN
1288 setmode(in, O_BINARY);
1289 setmode(out, O_BINARY);
1290 #endif
1291
1292 max = 0;
1293 if (in > max)
1294 max = in;
1295 if (out > max)
1296 max = out;
1297
1298 buffer_init(&iqueue);
1299 buffer_init(&oqueue);
1300
1301 set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask);
1302 rset = (fd_set *)xmalloc(set_size);
1303 wset = (fd_set *)xmalloc(set_size);
1304
1305 for (;;) {
1306 memset(rset, 0, set_size);
1307 memset(wset, 0, set_size);
1308
1309 /*
1310 * Ensure that we can read a full buffer and handle
1311 * the worst-case length packet it can generate,
1312 * otherwise apply backpressure by stopping reads.
1313 */
1314 if (buffer_check_alloc(&iqueue, sizeof(buf)) &&
1315 buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH))
1316 FD_SET(in, rset);
1317
1318 olen = buffer_len(&oqueue);
1319 if (olen > 0)
1320 FD_SET(out, wset);
1321
1322 if (select(max+1, rset, wset, NULL, NULL) < 0) {
1323 if (errno == EINTR)
1324 continue;
1325 error("select: %s", strerror(errno));
1326 cleanup_exit(2);
1327 }
1328
1329 /* copy stdin to iqueue */
1330 if (FD_ISSET(in, rset)) {
1331 len = read(in, buf, sizeof buf);
1332 if (len == 0) {
1333 debug("read eof");
1334 cleanup_exit(0);
1335 } else if (len < 0) {
1336 error("read: %s", strerror(errno));
1337 cleanup_exit(1);
1338 } else {
1339 buffer_append(&iqueue, buf, len);
1340 }
1341 }
1342 /* send oqueue to stdout */
1343 if (FD_ISSET(out, wset)) {
1344 len = write(out, buffer_ptr(&oqueue), olen);
1345 if (len < 0) {
1346 error("write: %s", strerror(errno));
1347 cleanup_exit(1);
1348 } else {
1349 buffer_consume(&oqueue, len);
1350 }
1351 }
1352
1353 /*
1354 * Process requests from client if we can fit the results
1355 * into the output buffer, otherwise stop processing input
1356 * and let the output queue drain.
1357 */
1358 if (buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH))
1359 process();
1360 }
1361
1362 /* NOTREACHED */
1363 return (0);
1364 }
1365