1 /* $OpenBSD: sftp-server.c,v 1.103 2014/01/17 06:23:24 dtucker Exp $ */
3 * Copyright (c) 2000-2004 Markus Friedl. All rights reserved.
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20 #include <sys/types.h>
21 #include <sys/param.h>
23 #ifdef HAVE_SYS_TIME_H
24 # include <sys/time.h>
26 #ifdef HAVE_SYS_MOUNT_H
27 #include <sys/mount.h>
29 #ifdef HAVE_SYS_STATVFS_H
30 #include <sys/statvfs.h>
32 #ifdef HAVE_SYS_PRCTL_H
33 #include <sys/prctl.h>
56 #include "sftp-common.h"
59 #define get_int64() buffer_get_int64(&iqueue);
60 #define get_int() buffer_get_int(&iqueue);
61 #define get_string(lenp) buffer_get_string(&iqueue, lenp);
64 static LogLevel log_level = SYSLOG_LEVEL_ERROR;
67 static struct passwd *pw = NULL;
68 static char *client_addr = NULL;
70 /* input and output queue */
74 /* Version of client */
77 /* SSH2_FXP_INIT received */
83 /* Requests that are allowed/denied */
84 static char *request_whitelist, *request_blacklist;
86 /* portable attributes, etc. */
87 typedef struct Stat Stat;
96 static void process_open(u_int32_t id);
97 static void process_close(u_int32_t id);
98 static void process_read(u_int32_t id);
99 static void process_write(u_int32_t id);
100 static void process_stat(u_int32_t id);
101 static void process_lstat(u_int32_t id);
102 static void process_fstat(u_int32_t id);
103 static void process_setstat(u_int32_t id);
104 static void process_fsetstat(u_int32_t id);
105 static void process_opendir(u_int32_t id);
106 static void process_readdir(u_int32_t id);
107 static void process_remove(u_int32_t id);
108 static void process_mkdir(u_int32_t id);
109 static void process_rmdir(u_int32_t id);
110 static void process_realpath(u_int32_t id);
111 static void process_rename(u_int32_t id);
112 static void process_readlink(u_int32_t id);
113 static void process_symlink(u_int32_t id);
114 static void process_extended_posix_rename(u_int32_t id);
115 static void process_extended_statvfs(u_int32_t id);
116 static void process_extended_fstatvfs(u_int32_t id);
117 static void process_extended_hardlink(u_int32_t id);
118 static void process_extended_fsync(u_int32_t id);
119 static void process_extended(u_int32_t id);
121 struct sftp_handler {
122 const char *name; /* user-visible name for fine-grained perms */
123 const char *ext_name; /* extended request name */
124 u_int type; /* packet type, for non extended packets */
125 void (*handler)(u_int32_t);
126 int does_write; /* if nonzero, banned for readonly mode */
129 struct sftp_handler handlers[] = {
130 /* NB. SSH2_FXP_OPEN does the readonly check in the handler itself */
131 { "open", NULL, SSH2_FXP_OPEN, process_open, 0 },
132 { "close", NULL, SSH2_FXP_CLOSE, process_close, 0 },
133 { "read", NULL, SSH2_FXP_READ, process_read, 0 },
134 { "write", NULL, SSH2_FXP_WRITE, process_write, 1 },
135 { "lstat", NULL, SSH2_FXP_LSTAT, process_lstat, 0 },
136 { "fstat", NULL, SSH2_FXP_FSTAT, process_fstat, 0 },
137 { "setstat", NULL, SSH2_FXP_SETSTAT, process_setstat, 1 },
138 { "fsetstat", NULL, SSH2_FXP_FSETSTAT, process_fsetstat, 1 },
139 { "opendir", NULL, SSH2_FXP_OPENDIR, process_opendir, 0 },
140 { "readdir", NULL, SSH2_FXP_READDIR, process_readdir, 0 },
141 { "remove", NULL, SSH2_FXP_REMOVE, process_remove, 1 },
142 { "mkdir", NULL, SSH2_FXP_MKDIR, process_mkdir, 1 },
143 { "rmdir", NULL, SSH2_FXP_RMDIR, process_rmdir, 1 },
144 { "realpath", NULL, SSH2_FXP_REALPATH, process_realpath, 0 },
145 { "stat", NULL, SSH2_FXP_STAT, process_stat, 0 },
146 { "rename", NULL, SSH2_FXP_RENAME, process_rename, 1 },
147 { "readlink", NULL, SSH2_FXP_READLINK, process_readlink, 0 },
148 { "symlink", NULL, SSH2_FXP_SYMLINK, process_symlink, 1 },
149 { NULL, NULL, 0, NULL, 0 }
152 /* SSH2_FXP_EXTENDED submessages */
153 struct sftp_handler extended_handlers[] = {
154 { "posix-rename", "posix-rename@openssh.com", 0,
155 process_extended_posix_rename, 1 },
156 { "statvfs", "statvfs@openssh.com", 0, process_extended_statvfs, 0 },
157 { "fstatvfs", "fstatvfs@openssh.com", 0, process_extended_fstatvfs, 0 },
158 { "hardlink", "hardlink@openssh.com", 0, process_extended_hardlink, 1 },
159 { "fsync", "fsync@openssh.com", 0, process_extended_fsync, 1 },
160 { NULL, NULL, 0, NULL, 0 }
164 request_permitted(struct sftp_handler *h)
168 if (readonly && h->does_write) {
169 verbose("Refusing %s request in read-only mode", h->name);
172 if (request_blacklist != NULL &&
173 ((result = match_list(h->name, request_blacklist, NULL))) != NULL) {
175 verbose("Refusing blacklisted %s request", h->name);
178 if (request_whitelist != NULL &&
179 ((result = match_list(h->name, request_whitelist, NULL))) != NULL) {
181 debug2("Permitting whitelisted %s request", h->name);
184 if (request_whitelist != NULL) {
185 verbose("Refusing non-whitelisted %s request", h->name);
192 errno_to_portable(int unixerrno)
204 ret = SSH2_FX_NO_SUCH_FILE;
209 ret = SSH2_FX_PERMISSION_DENIED;
213 ret = SSH2_FX_BAD_MESSAGE;
216 ret = SSH2_FX_OP_UNSUPPORTED;
219 ret = SSH2_FX_FAILURE;
226 flags_from_portable(int pflags)
230 if ((pflags & SSH2_FXF_READ) &&
231 (pflags & SSH2_FXF_WRITE)) {
233 } else if (pflags & SSH2_FXF_READ) {
235 } else if (pflags & SSH2_FXF_WRITE) {
238 if (pflags & SSH2_FXF_APPEND)
240 if (pflags & SSH2_FXF_CREAT)
242 if (pflags & SSH2_FXF_TRUNC)
244 if (pflags & SSH2_FXF_EXCL)
250 string_from_portable(int pflags)
252 static char ret[128];
256 #define PAPPEND(str) { \
258 strlcat(ret, ",", sizeof(ret)); \
259 strlcat(ret, str, sizeof(ret)); \
262 if (pflags & SSH2_FXF_READ)
264 if (pflags & SSH2_FXF_WRITE)
266 if (pflags & SSH2_FXF_APPEND)
268 if (pflags & SSH2_FXF_CREAT)
270 if (pflags & SSH2_FXF_TRUNC)
272 if (pflags & SSH2_FXF_EXCL)
281 return decode_attrib(&iqueue);
286 typedef struct Handle Handle;
293 u_int64_t bytes_read, bytes_write;
303 Handle *handles = NULL;
304 u_int num_handles = 0;
305 int first_unused_handle = -1;
307 static void handle_unused(int i)
309 handles[i].use = HANDLE_UNUSED;
310 handles[i].next_unused = first_unused_handle;
311 first_unused_handle = i;
315 handle_new(int use, const char *name, int fd, int flags, DIR *dirp)
319 if (first_unused_handle == -1) {
320 if (num_handles + 1 <= num_handles)
323 handles = xrealloc(handles, num_handles, sizeof(Handle));
324 handle_unused(num_handles - 1);
327 i = first_unused_handle;
328 first_unused_handle = handles[i].next_unused;
330 handles[i].use = use;
331 handles[i].dirp = dirp;
333 handles[i].flags = flags;
334 handles[i].name = xstrdup(name);
335 handles[i].bytes_read = handles[i].bytes_write = 0;
341 handle_is_ok(int i, int type)
343 return i >= 0 && (u_int)i < num_handles && handles[i].use == type;
347 handle_to_string(int handle, char **stringp, int *hlenp)
349 if (stringp == NULL || hlenp == NULL)
351 *stringp = xmalloc(sizeof(int32_t));
352 put_u32(*stringp, handle);
353 *hlenp = sizeof(int32_t);
358 handle_from_string(const char *handle, u_int hlen)
362 if (hlen != sizeof(int32_t))
364 val = get_u32(handle);
365 if (handle_is_ok(val, HANDLE_FILE) ||
366 handle_is_ok(val, HANDLE_DIR))
372 handle_to_name(int handle)
374 if (handle_is_ok(handle, HANDLE_DIR)||
375 handle_is_ok(handle, HANDLE_FILE))
376 return handles[handle].name;
381 handle_to_dir(int handle)
383 if (handle_is_ok(handle, HANDLE_DIR))
384 return handles[handle].dirp;
389 handle_to_fd(int handle)
391 if (handle_is_ok(handle, HANDLE_FILE))
392 return handles[handle].fd;
397 handle_to_flags(int handle)
399 if (handle_is_ok(handle, HANDLE_FILE))
400 return handles[handle].flags;
405 handle_update_read(int handle, ssize_t bytes)
407 if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0)
408 handles[handle].bytes_read += bytes;
412 handle_update_write(int handle, ssize_t bytes)
414 if (handle_is_ok(handle, HANDLE_FILE) && bytes > 0)
415 handles[handle].bytes_write += bytes;
419 handle_bytes_read(int handle)
421 if (handle_is_ok(handle, HANDLE_FILE))
422 return (handles[handle].bytes_read);
427 handle_bytes_write(int handle)
429 if (handle_is_ok(handle, HANDLE_FILE))
430 return (handles[handle].bytes_write);
435 handle_close(int handle)
439 if (handle_is_ok(handle, HANDLE_FILE)) {
440 ret = close(handles[handle].fd);
441 free(handles[handle].name);
442 handle_unused(handle);
443 } else if (handle_is_ok(handle, HANDLE_DIR)) {
444 ret = closedir(handles[handle].dirp);
445 free(handles[handle].name);
446 handle_unused(handle);
454 handle_log_close(int handle, char *emsg)
456 if (handle_is_ok(handle, HANDLE_FILE)) {
457 logit("%s%sclose \"%s\" bytes read %llu written %llu",
458 emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ",
459 handle_to_name(handle),
460 (unsigned long long)handle_bytes_read(handle),
461 (unsigned long long)handle_bytes_write(handle));
463 logit("%s%sclosedir \"%s\"",
464 emsg == NULL ? "" : emsg, emsg == NULL ? "" : " ",
465 handle_to_name(handle));
470 handle_log_exit(void)
474 for (i = 0; i < num_handles; i++)
475 if (handles[i].use != HANDLE_UNUSED)
476 handle_log_close(i, "forced");
486 handle = get_string(&hlen);
488 val = handle_from_string(handle, hlen);
498 int mlen = buffer_len(m);
500 buffer_put_int(&oqueue, mlen);
501 buffer_append(&oqueue, buffer_ptr(m), mlen);
502 buffer_consume(m, mlen);
506 status_to_message(u_int32_t status)
508 const char *status_messages[] = {
509 "Success", /* SSH_FX_OK */
510 "End of file", /* SSH_FX_EOF */
511 "No such file", /* SSH_FX_NO_SUCH_FILE */
512 "Permission denied", /* SSH_FX_PERMISSION_DENIED */
513 "Failure", /* SSH_FX_FAILURE */
514 "Bad message", /* SSH_FX_BAD_MESSAGE */
515 "No connection", /* SSH_FX_NO_CONNECTION */
516 "Connection lost", /* SSH_FX_CONNECTION_LOST */
517 "Operation unsupported", /* SSH_FX_OP_UNSUPPORTED */
518 "Unknown error" /* Others */
520 return (status_messages[MIN(status,SSH2_FX_MAX)]);
524 send_status(u_int32_t id, u_int32_t status)
528 debug3("request %u: sent status %u", id, status);
529 if (log_level > SYSLOG_LEVEL_VERBOSE ||
530 (status != SSH2_FX_OK && status != SSH2_FX_EOF))
531 logit("sent status %s", status_to_message(status));
533 buffer_put_char(&msg, SSH2_FXP_STATUS);
534 buffer_put_int(&msg, id);
535 buffer_put_int(&msg, status);
537 buffer_put_cstring(&msg, status_to_message(status));
538 buffer_put_cstring(&msg, "");
544 send_data_or_handle(char type, u_int32_t id, const char *data, int dlen)
549 buffer_put_char(&msg, type);
550 buffer_put_int(&msg, id);
551 buffer_put_string(&msg, data, dlen);
557 send_data(u_int32_t id, const char *data, int dlen)
559 debug("request %u: sent data len %d", id, dlen);
560 send_data_or_handle(SSH2_FXP_DATA, id, data, dlen);
564 send_handle(u_int32_t id, int handle)
569 handle_to_string(handle, &string, &hlen);
570 debug("request %u: sent handle handle %d", id, handle);
571 send_data_or_handle(SSH2_FXP_HANDLE, id, string, hlen);
576 send_names(u_int32_t id, int count, const Stat *stats)
582 buffer_put_char(&msg, SSH2_FXP_NAME);
583 buffer_put_int(&msg, id);
584 buffer_put_int(&msg, count);
585 debug("request %u: sent names count %d", id, count);
586 for (i = 0; i < count; i++) {
587 buffer_put_cstring(&msg, stats[i].name);
588 buffer_put_cstring(&msg, stats[i].long_name);
589 encode_attrib(&msg, &stats[i].attrib);
596 send_attrib(u_int32_t id, const Attrib *a)
600 debug("request %u: sent attrib have 0x%x", id, a->flags);
602 buffer_put_char(&msg, SSH2_FXP_ATTRS);
603 buffer_put_int(&msg, id);
604 encode_attrib(&msg, a);
610 send_statvfs(u_int32_t id, struct statvfs *st)
615 flag = (st->f_flag & ST_RDONLY) ? SSH2_FXE_STATVFS_ST_RDONLY : 0;
616 flag |= (st->f_flag & ST_NOSUID) ? SSH2_FXE_STATVFS_ST_NOSUID : 0;
619 buffer_put_char(&msg, SSH2_FXP_EXTENDED_REPLY);
620 buffer_put_int(&msg, id);
621 buffer_put_int64(&msg, st->f_bsize);
622 buffer_put_int64(&msg, st->f_frsize);
623 buffer_put_int64(&msg, st->f_blocks);
624 buffer_put_int64(&msg, st->f_bfree);
625 buffer_put_int64(&msg, st->f_bavail);
626 buffer_put_int64(&msg, st->f_files);
627 buffer_put_int64(&msg, st->f_ffree);
628 buffer_put_int64(&msg, st->f_favail);
629 buffer_put_int64(&msg, FSID_TO_ULONG(st->f_fsid));
630 buffer_put_int64(&msg, flag);
631 buffer_put_int64(&msg, st->f_namemax);
644 verbose("received client version %u", version);
646 buffer_put_char(&msg, SSH2_FXP_VERSION);
647 buffer_put_int(&msg, SSH2_FILEXFER_VERSION);
648 /* POSIX rename extension */
649 buffer_put_cstring(&msg, "posix-rename@openssh.com");
650 buffer_put_cstring(&msg, "1"); /* version */
651 /* statvfs extension */
652 buffer_put_cstring(&msg, "statvfs@openssh.com");
653 buffer_put_cstring(&msg, "2"); /* version */
654 /* fstatvfs extension */
655 buffer_put_cstring(&msg, "fstatvfs@openssh.com");
656 buffer_put_cstring(&msg, "2"); /* version */
657 /* hardlink extension */
658 buffer_put_cstring(&msg, "hardlink@openssh.com");
659 buffer_put_cstring(&msg, "1"); /* version */
660 /* fsync extension */
661 buffer_put_cstring(&msg, "fsync@openssh.com");
662 buffer_put_cstring(&msg, "1"); /* version */
668 process_open(u_int32_t id)
673 int handle, fd, flags, mode, status = SSH2_FX_FAILURE;
675 name = get_string(NULL);
676 pflags = get_int(); /* portable flags */
677 debug3("request %u: open flags %d", id, pflags);
679 flags = flags_from_portable(pflags);
680 mode = (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ? a->perm : 0666;
681 logit("open \"%s\" flags %s mode 0%o",
682 name, string_from_portable(pflags), mode);
684 ((flags & O_ACCMODE) == O_WRONLY ||
685 (flags & O_ACCMODE) == O_RDWR)) {
686 verbose("Refusing open request in read-only mode");
687 status = SSH2_FX_PERMISSION_DENIED;
689 fd = open(name, flags, mode);
691 status = errno_to_portable(errno);
693 handle = handle_new(HANDLE_FILE, name, fd, flags, NULL);
697 send_handle(id, handle);
702 if (status != SSH2_FX_OK)
703 send_status(id, status);
708 process_close(u_int32_t id)
710 int handle, ret, status = SSH2_FX_FAILURE;
712 handle = get_handle();
713 debug3("request %u: close handle %u", id, handle);
714 handle_log_close(handle, NULL);
715 ret = handle_close(handle);
716 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
717 send_status(id, status);
721 process_read(u_int32_t id)
725 int handle, fd, ret, status = SSH2_FX_FAILURE;
728 handle = get_handle();
732 debug("request %u: read \"%s\" (handle %d) off %llu len %d",
733 id, handle_to_name(handle), handle, (unsigned long long)off, len);
734 if (len > sizeof buf) {
736 debug2("read change len %d", len);
738 fd = handle_to_fd(handle);
740 if (lseek(fd, off, SEEK_SET) < 0) {
741 error("process_read: seek failed");
742 status = errno_to_portable(errno);
744 ret = read(fd, buf, len);
746 status = errno_to_portable(errno);
747 } else if (ret == 0) {
748 status = SSH2_FX_EOF;
750 send_data(id, buf, ret);
752 handle_update_read(handle, ret);
756 if (status != SSH2_FX_OK)
757 send_status(id, status);
761 process_write(u_int32_t id)
765 int handle, fd, ret, status;
768 handle = get_handle();
770 data = get_string(&len);
772 debug("request %u: write \"%s\" (handle %d) off %llu len %d",
773 id, handle_to_name(handle), handle, (unsigned long long)off, len);
774 fd = handle_to_fd(handle);
777 status = SSH2_FX_FAILURE;
779 if (!(handle_to_flags(handle) & O_APPEND) &&
780 lseek(fd, off, SEEK_SET) < 0) {
781 status = errno_to_portable(errno);
782 error("process_write: seek failed");
785 ret = write(fd, data, len);
787 error("process_write: write failed");
788 status = errno_to_portable(errno);
789 } else if ((size_t)ret == len) {
791 handle_update_write(handle, ret);
793 debug2("nothing at all written");
794 status = SSH2_FX_FAILURE;
798 send_status(id, status);
803 process_do_stat(u_int32_t id, int do_lstat)
808 int ret, status = SSH2_FX_FAILURE;
810 name = get_string(NULL);
811 debug3("request %u: %sstat", id, do_lstat ? "l" : "");
812 verbose("%sstat name \"%s\"", do_lstat ? "l" : "", name);
813 ret = do_lstat ? lstat(name, &st) : stat(name, &st);
815 status = errno_to_portable(errno);
817 stat_to_attrib(&st, &a);
821 if (status != SSH2_FX_OK)
822 send_status(id, status);
827 process_stat(u_int32_t id)
829 process_do_stat(id, 0);
833 process_lstat(u_int32_t id)
835 process_do_stat(id, 1);
839 process_fstat(u_int32_t id)
843 int fd, ret, handle, status = SSH2_FX_FAILURE;
845 handle = get_handle();
846 debug("request %u: fstat \"%s\" (handle %u)",
847 id, handle_to_name(handle), handle);
848 fd = handle_to_fd(handle);
850 ret = fstat(fd, &st);
852 status = errno_to_portable(errno);
854 stat_to_attrib(&st, &a);
859 if (status != SSH2_FX_OK)
860 send_status(id, status);
863 static struct timeval *
864 attrib_to_tv(const Attrib *a)
866 static struct timeval tv[2];
868 tv[0].tv_sec = a->atime;
870 tv[1].tv_sec = a->mtime;
876 process_setstat(u_int32_t id)
880 int status = SSH2_FX_OK, ret;
882 name = get_string(NULL);
884 debug("request %u: setstat name \"%s\"", id, name);
885 if (a->flags & SSH2_FILEXFER_ATTR_SIZE) {
886 logit("set \"%s\" size %llu",
887 name, (unsigned long long)a->size);
888 ret = truncate(name, a->size);
890 status = errno_to_portable(errno);
892 if (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) {
893 logit("set \"%s\" mode %04o", name, a->perm);
894 ret = chmod(name, a->perm & 07777);
896 status = errno_to_portable(errno);
898 if (a->flags & SSH2_FILEXFER_ATTR_ACMODTIME) {
902 strftime(buf, sizeof(buf), "%Y%m%d-%H:%M:%S",
904 logit("set \"%s\" modtime %s", name, buf);
905 ret = utimes(name, attrib_to_tv(a));
907 status = errno_to_portable(errno);
909 if (a->flags & SSH2_FILEXFER_ATTR_UIDGID) {
910 logit("set \"%s\" owner %lu group %lu", name,
911 (u_long)a->uid, (u_long)a->gid);
912 ret = chown(name, a->uid, a->gid);
914 status = errno_to_portable(errno);
916 send_status(id, status);
921 process_fsetstat(u_int32_t id)
925 int status = SSH2_FX_OK;
927 handle = get_handle();
929 debug("request %u: fsetstat handle %d", id, handle);
930 fd = handle_to_fd(handle);
932 status = SSH2_FX_FAILURE;
934 char *name = handle_to_name(handle);
936 if (a->flags & SSH2_FILEXFER_ATTR_SIZE) {
937 logit("set \"%s\" size %llu",
938 name, (unsigned long long)a->size);
939 ret = ftruncate(fd, a->size);
941 status = errno_to_portable(errno);
943 if (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) {
944 logit("set \"%s\" mode %04o", name, a->perm);
946 ret = fchmod(fd, a->perm & 07777);
948 ret = chmod(name, a->perm & 07777);
951 status = errno_to_portable(errno);
953 if (a->flags & SSH2_FILEXFER_ATTR_ACMODTIME) {
957 strftime(buf, sizeof(buf), "%Y%m%d-%H:%M:%S",
959 logit("set \"%s\" modtime %s", name, buf);
961 ret = futimes(fd, attrib_to_tv(a));
963 ret = utimes(name, attrib_to_tv(a));
966 status = errno_to_portable(errno);
968 if (a->flags & SSH2_FILEXFER_ATTR_UIDGID) {
969 logit("set \"%s\" owner %lu group %lu", name,
970 (u_long)a->uid, (u_long)a->gid);
972 ret = fchown(fd, a->uid, a->gid);
974 ret = chown(name, a->uid, a->gid);
977 status = errno_to_portable(errno);
980 send_status(id, status);
984 process_opendir(u_int32_t id)
988 int handle, status = SSH2_FX_FAILURE;
990 path = get_string(NULL);
991 debug3("request %u: opendir", id);
992 logit("opendir \"%s\"", path);
993 dirp = opendir(path);
995 status = errno_to_portable(errno);
997 handle = handle_new(HANDLE_DIR, path, 0, 0, dirp);
1001 send_handle(id, handle);
1002 status = SSH2_FX_OK;
1006 if (status != SSH2_FX_OK)
1007 send_status(id, status);
1012 process_readdir(u_int32_t id)
1019 handle = get_handle();
1020 debug("request %u: readdir \"%s\" (handle %d)", id,
1021 handle_to_name(handle), handle);
1022 dirp = handle_to_dir(handle);
1023 path = handle_to_name(handle);
1024 if (dirp == NULL || path == NULL) {
1025 send_status(id, SSH2_FX_FAILURE);
1028 char pathname[MAXPATHLEN];
1030 int nstats = 10, count = 0, i;
1032 stats = xcalloc(nstats, sizeof(Stat));
1033 while ((dp = readdir(dirp)) != NULL) {
1034 if (count >= nstats) {
1036 stats = xrealloc(stats, nstats, sizeof(Stat));
1038 /* XXX OVERFLOW ? */
1039 snprintf(pathname, sizeof pathname, "%s%s%s", path,
1040 strcmp(path, "/") ? "/" : "", dp->d_name);
1041 if (lstat(pathname, &st) < 0)
1043 stat_to_attrib(&st, &(stats[count].attrib));
1044 stats[count].name = xstrdup(dp->d_name);
1045 stats[count].long_name = ls_file(dp->d_name, &st, 0, 0);
1047 /* send up to 100 entries in one message */
1048 /* XXX check packet size instead */
1053 send_names(id, count, stats);
1054 for (i = 0; i < count; i++) {
1055 free(stats[i].name);
1056 free(stats[i].long_name);
1059 send_status(id, SSH2_FX_EOF);
1066 process_remove(u_int32_t id)
1069 int status = SSH2_FX_FAILURE;
1072 name = get_string(NULL);
1073 debug3("request %u: remove", id);
1074 logit("remove name \"%s\"", name);
1076 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
1077 send_status(id, status);
1082 process_mkdir(u_int32_t id)
1086 int ret, mode, status = SSH2_FX_FAILURE;
1088 name = get_string(NULL);
1090 mode = (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ?
1091 a->perm & 07777 : 0777;
1092 debug3("request %u: mkdir", id);
1093 logit("mkdir name \"%s\" mode 0%o", name, mode);
1094 ret = mkdir(name, mode);
1095 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
1096 send_status(id, status);
1101 process_rmdir(u_int32_t id)
1106 name = get_string(NULL);
1107 debug3("request %u: rmdir", id);
1108 logit("rmdir name \"%s\"", name);
1110 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
1111 send_status(id, status);
1116 process_realpath(u_int32_t id)
1118 char resolvedname[MAXPATHLEN];
1121 path = get_string(NULL);
1122 if (path[0] == '\0') {
1124 path = xstrdup(".");
1126 debug3("request %u: realpath", id);
1127 verbose("realpath \"%s\"", path);
1128 if (realpath(path, resolvedname) == NULL) {
1129 send_status(id, errno_to_portable(errno));
1132 attrib_clear(&s.attrib);
1133 s.name = s.long_name = resolvedname;
1134 send_names(id, 1, &s);
1140 process_rename(u_int32_t id)
1142 char *oldpath, *newpath;
1146 oldpath = get_string(NULL);
1147 newpath = get_string(NULL);
1148 debug3("request %u: rename", id);
1149 logit("rename old \"%s\" new \"%s\"", oldpath, newpath);
1150 status = SSH2_FX_FAILURE;
1151 if (lstat(oldpath, &sb) == -1)
1152 status = errno_to_portable(errno);
1153 else if (S_ISREG(sb.st_mode)) {
1154 /* Race-free rename of regular files */
1155 if (link(oldpath, newpath) == -1) {
1156 if (errno == EOPNOTSUPP || errno == ENOSYS
1160 #ifdef LINK_OPNOTSUPP_ERRNO
1161 || errno == LINK_OPNOTSUPP_ERRNO
1167 * fs doesn't support links, so fall back to
1168 * stat+rename. This is racy.
1170 if (stat(newpath, &st) == -1) {
1171 if (rename(oldpath, newpath) == -1)
1173 errno_to_portable(errno);
1175 status = SSH2_FX_OK;
1178 status = errno_to_portable(errno);
1180 } else if (unlink(oldpath) == -1) {
1181 status = errno_to_portable(errno);
1182 /* clean spare link */
1185 status = SSH2_FX_OK;
1186 } else if (stat(newpath, &sb) == -1) {
1187 if (rename(oldpath, newpath) == -1)
1188 status = errno_to_portable(errno);
1190 status = SSH2_FX_OK;
1192 send_status(id, status);
1198 process_readlink(u_int32_t id)
1201 char buf[MAXPATHLEN];
1204 path = get_string(NULL);
1205 debug3("request %u: readlink", id);
1206 verbose("readlink \"%s\"", path);
1207 if ((len = readlink(path, buf, sizeof(buf) - 1)) == -1)
1208 send_status(id, errno_to_portable(errno));
1213 attrib_clear(&s.attrib);
1214 s.name = s.long_name = buf;
1215 send_names(id, 1, &s);
1221 process_symlink(u_int32_t id)
1223 char *oldpath, *newpath;
1226 oldpath = get_string(NULL);
1227 newpath = get_string(NULL);
1228 debug3("request %u: symlink", id);
1229 logit("symlink old \"%s\" new \"%s\"", oldpath, newpath);
1230 /* this will fail if 'newpath' exists */
1231 ret = symlink(oldpath, newpath);
1232 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
1233 send_status(id, status);
1239 process_extended_posix_rename(u_int32_t id)
1241 char *oldpath, *newpath;
1244 oldpath = get_string(NULL);
1245 newpath = get_string(NULL);
1246 debug3("request %u: posix-rename", id);
1247 logit("posix-rename old \"%s\" new \"%s\"", oldpath, newpath);
1248 ret = rename(oldpath, newpath);
1249 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
1250 send_status(id, status);
1256 process_extended_statvfs(u_int32_t id)
1261 path = get_string(NULL);
1262 debug3("request %u: statvfs", id);
1263 logit("statvfs \"%s\"", path);
1265 if (statvfs(path, &st) != 0)
1266 send_status(id, errno_to_portable(errno));
1268 send_statvfs(id, &st);
1273 process_extended_fstatvfs(u_int32_t id)
1278 handle = get_handle();
1279 debug("request %u: fstatvfs \"%s\" (handle %u)",
1280 id, handle_to_name(handle), handle);
1281 if ((fd = handle_to_fd(handle)) < 0) {
1282 send_status(id, SSH2_FX_FAILURE);
1285 if (fstatvfs(fd, &st) != 0)
1286 send_status(id, errno_to_portable(errno));
1288 send_statvfs(id, &st);
1292 process_extended_hardlink(u_int32_t id)
1294 char *oldpath, *newpath;
1297 oldpath = get_string(NULL);
1298 newpath = get_string(NULL);
1299 debug3("request %u: hardlink", id);
1300 logit("hardlink old \"%s\" new \"%s\"", oldpath, newpath);
1301 ret = link(oldpath, newpath);
1302 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
1303 send_status(id, status);
1309 process_extended_fsync(u_int32_t id)
1311 int handle, fd, ret, status = SSH2_FX_OP_UNSUPPORTED;
1313 handle = get_handle();
1314 debug3("request %u: fsync (handle %u)", id, handle);
1315 verbose("fsync \"%s\"", handle_to_name(handle));
1316 if ((fd = handle_to_fd(handle)) < 0)
1317 status = SSH2_FX_NO_SUCH_FILE;
1318 else if (handle_is_ok(handle, HANDLE_FILE)) {
1320 status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
1322 send_status(id, status);
1326 process_extended(u_int32_t id)
1331 request = get_string(NULL);
1332 for (i = 0; extended_handlers[i].handler != NULL; i++) {
1333 if (strcmp(request, extended_handlers[i].ext_name) == 0) {
1334 if (!request_permitted(&extended_handlers[i]))
1335 send_status(id, SSH2_FX_PERMISSION_DENIED);
1337 extended_handlers[i].handler(id);
1341 if (extended_handlers[i].handler == NULL) {
1342 error("Unknown extended request \"%.100s\"", request);
1343 send_status(id, SSH2_FX_OP_UNSUPPORTED); /* MUST */
1348 /* stolen from ssh-agent */
1353 u_int msg_len, buf_len, consumed, type, i;
1357 buf_len = buffer_len(&iqueue);
1359 return; /* Incomplete message. */
1360 cp = buffer_ptr(&iqueue);
1361 msg_len = get_u32(cp);
1362 if (msg_len > SFTP_MAX_MSG_LENGTH) {
1363 error("bad message from %s local user %s",
1364 client_addr, pw->pw_name);
1365 sftp_server_cleanup_exit(11);
1367 if (buf_len < msg_len + 4)
1369 buffer_consume(&iqueue, 4);
1371 type = buffer_get_char(&iqueue);
1378 case SSH2_FXP_EXTENDED:
1380 fatal("Received extended request before init");
1382 process_extended(id);
1386 fatal("Received %u request before init", type);
1388 for (i = 0; handlers[i].handler != NULL; i++) {
1389 if (type == handlers[i].type) {
1390 if (!request_permitted(&handlers[i])) {
1392 SSH2_FX_PERMISSION_DENIED);
1394 handlers[i].handler(id);
1399 if (handlers[i].handler == NULL)
1400 error("Unknown message %u", type);
1402 /* discard the remaining bytes from the current packet */
1403 if (buf_len < buffer_len(&iqueue)) {
1404 error("iqueue grew unexpectedly");
1405 sftp_server_cleanup_exit(255);
1407 consumed = buf_len - buffer_len(&iqueue);
1408 if (msg_len < consumed) {
1409 error("msg_len %u < consumed %u", msg_len, consumed);
1410 sftp_server_cleanup_exit(255);
1412 if (msg_len > consumed)
1413 buffer_consume(&iqueue, msg_len - consumed);
1416 /* Cleanup handler that logs active handles upon normal exit */
1418 sftp_server_cleanup_exit(int i)
1420 if (pw != NULL && client_addr != NULL) {
1422 logit("session closed for local user %s from [%s]",
1423 pw->pw_name, client_addr);
1429 sftp_server_usage(void)
1431 extern char *__progname;
1434 "usage: %s [-ehR] [-d start_directory] [-f log_facility] "
1435 "[-l log_level]\n\t[-P blacklisted_requests] "
1436 "[-p whitelisted_requests] [-u umask]\n"
1437 " %s -Q protocol_feature\n",
1438 __progname, __progname);
1443 sftp_server_main(int argc, char **argv, struct passwd *user_pw)
1445 fd_set *rset, *wset;
1446 int i, in, out, max, ch, skipargs = 0, log_stderr = 0;
1447 ssize_t len, olen, set_size;
1448 SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
1449 char *cp, *homedir = NULL, buf[4*4096];
1452 extern char *optarg;
1453 extern char *__progname;
1455 __progname = ssh_get_progname(argv[0]);
1456 log_init(__progname, log_level, log_facility, log_stderr);
1458 pw = pwcopy(user_pw);
1460 while (!skipargs && (ch = getopt(argc, argv,
1461 "d:f:l:P:p:Q:u:cehR")) != -1) {
1464 if (strcasecmp(optarg, "requests") != 0) {
1465 fprintf(stderr, "Invalid query type\n");
1468 for (i = 0; handlers[i].handler != NULL; i++)
1469 printf("%s\n", handlers[i].name);
1470 for (i = 0; extended_handlers[i].handler != NULL; i++)
1471 printf("%s\n", extended_handlers[i].name);
1479 * Ignore all arguments if we are invoked as a
1480 * shell using "sftp-server -c command"
1488 log_level = log_level_number(optarg);
1489 if (log_level == SYSLOG_LEVEL_NOT_SET)
1490 error("Invalid log level \"%s\"", optarg);
1493 log_facility = log_facility_number(optarg);
1494 if (log_facility == SYSLOG_FACILITY_NOT_SET)
1495 error("Invalid log facility \"%s\"", optarg);
1498 cp = tilde_expand_filename(optarg, user_pw->pw_uid);
1499 homedir = percent_expand(cp, "d", user_pw->pw_dir,
1500 "u", user_pw->pw_name, (char *)NULL);
1504 if (request_whitelist != NULL)
1505 fatal("Permitted requests already set");
1506 request_whitelist = xstrdup(optarg);
1509 if (request_blacklist != NULL)
1510 fatal("Refused requests already set");
1511 request_blacklist = xstrdup(optarg);
1515 mask = strtol(optarg, &cp, 8);
1516 if (mask < 0 || mask > 0777 || *cp != '\0' ||
1517 cp == optarg || (mask == 0 && errno != 0))
1518 fatal("Invalid umask \"%s\"", optarg);
1519 (void)umask((mode_t)mask);
1523 sftp_server_usage();
1527 log_init(__progname, log_level, log_facility, log_stderr);
1529 #if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE)
1531 * On Linux, we should try to avoid making /proc/self/{mem,maps}
1532 * available to the user so that sftp access doesn't automatically
1533 * imply arbitrary code execution access that will break
1534 * restricted configurations.
1536 if (prctl(PR_SET_DUMPABLE, 0) != 0)
1537 fatal("unable to make the process undumpable");
1538 #endif /* defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE) */
1540 if ((cp = getenv("SSH_CONNECTION")) != NULL) {
1541 client_addr = xstrdup(cp);
1542 if ((cp = strchr(client_addr, ' ')) == NULL) {
1543 error("Malformed SSH_CONNECTION variable: \"%s\"",
1544 getenv("SSH_CONNECTION"));
1545 sftp_server_cleanup_exit(255);
1549 client_addr = xstrdup("UNKNOWN");
1551 logit("session opened for local user %s from [%s]",
1552 pw->pw_name, client_addr);
1555 out = STDOUT_FILENO;
1558 setmode(in, O_BINARY);
1559 setmode(out, O_BINARY);
1568 buffer_init(&iqueue);
1569 buffer_init(&oqueue);
1571 set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask);
1572 rset = (fd_set *)xmalloc(set_size);
1573 wset = (fd_set *)xmalloc(set_size);
1575 if (homedir != NULL) {
1576 if (chdir(homedir) != 0) {
1577 error("chdir to \"%s\" failed: %s", homedir,
1583 memset(rset, 0, set_size);
1584 memset(wset, 0, set_size);
1587 * Ensure that we can read a full buffer and handle
1588 * the worst-case length packet it can generate,
1589 * otherwise apply backpressure by stopping reads.
1591 if (buffer_check_alloc(&iqueue, sizeof(buf)) &&
1592 buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH))
1595 olen = buffer_len(&oqueue);
1599 if (select(max+1, rset, wset, NULL, NULL) < 0) {
1602 error("select: %s", strerror(errno));
1603 sftp_server_cleanup_exit(2);
1606 /* copy stdin to iqueue */
1607 if (FD_ISSET(in, rset)) {
1608 len = read(in, buf, sizeof buf);
1611 sftp_server_cleanup_exit(0);
1612 } else if (len < 0) {
1613 error("read: %s", strerror(errno));
1614 sftp_server_cleanup_exit(1);
1616 buffer_append(&iqueue, buf, len);
1619 /* send oqueue to stdout */
1620 if (FD_ISSET(out, wset)) {
1621 len = write(out, buffer_ptr(&oqueue), olen);
1623 error("write: %s", strerror(errno));
1624 sftp_server_cleanup_exit(1);
1626 buffer_consume(&oqueue, len);
1631 * Process requests from client if we can fit the results
1632 * into the output buffer, otherwise stop processing input
1633 * and let the output queue drain.
1635 if (buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH))