2 * sftp.c: SFTP generic client code.
14 #define GET_32BIT(cp) \
15 (((unsigned long)(unsigned char)(cp)[0] << 24) | \
16 ((unsigned long)(unsigned char)(cp)[1] << 16) | \
17 ((unsigned long)(unsigned char)(cp)[2] << 8) | \
18 ((unsigned long)(unsigned char)(cp)[3]))
20 #define PUT_32BIT(cp, value) { \
21 (cp)[0] = (unsigned char)((value) >> 24); \
22 (cp)[1] = (unsigned char)((value) >> 16); \
23 (cp)[2] = (unsigned char)((value) >> 8); \
24 (cp)[3] = (unsigned char)(value); }
33 static const char *fxp_error_message
;
34 static int fxp_errtype
;
36 /* ----------------------------------------------------------------------
37 * SFTP packet construction functions.
39 static void sftp_pkt_ensure(struct sftp_packet
*pkt
, int length
)
41 if (pkt
->maxlen
< length
) {
42 pkt
->maxlen
= length
+ 256;
43 pkt
->data
= srealloc(pkt
->data
, pkt
->maxlen
);
46 static void sftp_pkt_adddata(struct sftp_packet
*pkt
, void *data
, int len
)
49 sftp_pkt_ensure(pkt
, pkt
->length
);
50 memcpy(pkt
->data
+ pkt
->length
- len
, data
, len
);
52 static void sftp_pkt_addbyte(struct sftp_packet
*pkt
, unsigned char byte
)
54 sftp_pkt_adddata(pkt
, &byte
, 1);
56 static struct sftp_packet
*sftp_pkt_init(int pkt_type
)
58 struct sftp_packet
*pkt
;
59 pkt
= smalloc(sizeof(struct sftp_packet
));
64 sftp_pkt_addbyte(pkt
, (unsigned char) pkt_type
);
65 fxp_error_message
= NULL
;
68 static void sftp_pkt_addbool(struct sftp_packet
*pkt
, unsigned char value
)
70 sftp_pkt_adddata(pkt
, &value
, 1);
72 static void sftp_pkt_adduint32(struct sftp_packet
*pkt
,
77 sftp_pkt_adddata(pkt
, x
, 4);
79 static void sftp_pkt_adduint64(struct sftp_packet
*pkt
, uint64 value
)
82 PUT_32BIT(x
, value
.hi
);
83 PUT_32BIT(x
+ 4, value
.lo
);
84 sftp_pkt_adddata(pkt
, x
, 8);
86 static void sftp_pkt_addstring_start(struct sftp_packet
*pkt
)
88 sftp_pkt_adduint32(pkt
, 0);
89 pkt
->savedpos
= pkt
->length
;
91 static void sftp_pkt_addstring_str(struct sftp_packet
*pkt
, char *data
)
93 sftp_pkt_adddata(pkt
, data
, strlen(data
));
94 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
96 static void sftp_pkt_addstring_data(struct sftp_packet
*pkt
,
99 sftp_pkt_adddata(pkt
, data
, len
);
100 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
102 static void sftp_pkt_addstring(struct sftp_packet
*pkt
, char *data
)
104 sftp_pkt_addstring_start(pkt
);
105 sftp_pkt_addstring_str(pkt
, data
);
107 static void sftp_pkt_addattrs(struct sftp_packet
*pkt
, struct fxp_attrs attrs
)
109 sftp_pkt_adduint32(pkt
, attrs
.flags
);
110 if (attrs
.flags
& SSH_FILEXFER_ATTR_SIZE
) {
111 sftp_pkt_adduint32(pkt
, attrs
.size
.hi
);
112 sftp_pkt_adduint32(pkt
, attrs
.size
.lo
);
114 if (attrs
.flags
& SSH_FILEXFER_ATTR_UIDGID
) {
115 sftp_pkt_adduint32(pkt
, attrs
.uid
);
116 sftp_pkt_adduint32(pkt
, attrs
.gid
);
118 if (attrs
.flags
& SSH_FILEXFER_ATTR_PERMISSIONS
) {
119 sftp_pkt_adduint32(pkt
, attrs
.permissions
);
121 if (attrs
.flags
& SSH_FILEXFER_ATTR_ACMODTIME
) {
122 sftp_pkt_adduint32(pkt
, attrs
.atime
);
123 sftp_pkt_adduint32(pkt
, attrs
.mtime
);
125 if (attrs
.flags
& SSH_FILEXFER_ATTR_EXTENDED
) {
127 * We currently don't support sending any extended
133 /* ----------------------------------------------------------------------
134 * SFTP packet decode functions.
137 static unsigned char sftp_pkt_getbyte(struct sftp_packet
*pkt
)
140 if (pkt
->length
- pkt
->savedpos
< 1)
141 return 0; /* arrgh, no way to decline (FIXME?) */
142 value
= (unsigned char) pkt
->data
[pkt
->savedpos
];
146 static unsigned long sftp_pkt_getuint32(struct sftp_packet
*pkt
)
149 if (pkt
->length
- pkt
->savedpos
< 4)
150 return 0; /* arrgh, no way to decline (FIXME?) */
151 value
= GET_32BIT(pkt
->data
+ pkt
->savedpos
);
155 static void sftp_pkt_getstring(struct sftp_packet
*pkt
,
156 char **p
, int *length
)
159 if (pkt
->length
- pkt
->savedpos
< 4)
161 *length
= GET_32BIT(pkt
->data
+ pkt
->savedpos
);
163 if (pkt
->length
- pkt
->savedpos
< *length
)
165 *p
= pkt
->data
+ pkt
->savedpos
;
166 pkt
->savedpos
+= *length
;
168 static struct fxp_attrs
sftp_pkt_getattrs(struct sftp_packet
*pkt
)
170 struct fxp_attrs ret
;
171 ret
.flags
= sftp_pkt_getuint32(pkt
);
172 if (ret
.flags
& SSH_FILEXFER_ATTR_SIZE
) {
173 unsigned long hi
, lo
;
174 hi
= sftp_pkt_getuint32(pkt
);
175 lo
= sftp_pkt_getuint32(pkt
);
176 ret
.size
= uint64_make(hi
, lo
);
178 if (ret
.flags
& SSH_FILEXFER_ATTR_UIDGID
) {
179 ret
.uid
= sftp_pkt_getuint32(pkt
);
180 ret
.gid
= sftp_pkt_getuint32(pkt
);
182 if (ret
.flags
& SSH_FILEXFER_ATTR_PERMISSIONS
) {
183 ret
.permissions
= sftp_pkt_getuint32(pkt
);
185 if (ret
.flags
& SSH_FILEXFER_ATTR_ACMODTIME
) {
186 ret
.atime
= sftp_pkt_getuint32(pkt
);
187 ret
.mtime
= sftp_pkt_getuint32(pkt
);
189 if (ret
.flags
& SSH_FILEXFER_ATTR_EXTENDED
) {
191 count
= sftp_pkt_getuint32(pkt
);
196 * We should try to analyse these, if we ever find one
199 sftp_pkt_getstring(pkt
, &str
, &len
);
200 sftp_pkt_getstring(pkt
, &str
, &len
);
205 static void sftp_pkt_free(struct sftp_packet
*pkt
)
212 /* ----------------------------------------------------------------------
213 * Send and receive packet functions.
215 int sftp_send(struct sftp_packet
*pkt
)
219 PUT_32BIT(x
, pkt
->length
);
220 ret
= (sftp_senddata(x
, 4) && sftp_senddata(pkt
->data
, pkt
->length
));
224 struct sftp_packet
*sftp_recv(void)
226 struct sftp_packet
*pkt
;
229 if (!sftp_recvdata(x
, 4))
232 pkt
= smalloc(sizeof(struct sftp_packet
));
234 pkt
->length
= pkt
->maxlen
= GET_32BIT(x
);
235 pkt
->data
= smalloc(pkt
->length
);
237 if (!sftp_recvdata(pkt
->data
, pkt
->length
)) {
242 pkt
->type
= sftp_pkt_getbyte(pkt
);
247 /* ----------------------------------------------------------------------
248 * String handling routines.
251 static char *mkstr(char *s
, int len
)
253 char *p
= smalloc(len
+ 1);
259 /* ----------------------------------------------------------------------
264 * Deal with (and free) an FXP_STATUS packet. Return 1 if
265 * SSH_FX_OK, 0 if SSH_FX_EOF, and -1 for anything else (error).
266 * Also place the status into fxp_errtype.
268 static int fxp_got_status(struct sftp_packet
*pktin
)
270 static const char *const messages
[] = {
271 /* SSH_FX_OK. The only time we will display a _message_ for this
272 * is if we were expecting something other than FXP_STATUS on
273 * success, so this is actually an error message! */
274 "unexpected OK response",
276 "no such file or directory",
282 "operation unsupported",
285 if (pktin
->type
!= SSH_FXP_STATUS
) {
286 fxp_error_message
= "expected FXP_STATUS packet";
289 fxp_errtype
= sftp_pkt_getuint32(pktin
);
290 if (fxp_errtype
< 0 ||
291 fxp_errtype
>= sizeof(messages
) / sizeof(*messages
))
292 fxp_error_message
= "unknown error code";
294 fxp_error_message
= messages
[fxp_errtype
];
297 if (fxp_errtype
== SSH_FX_OK
)
299 else if (fxp_errtype
== SSH_FX_EOF
)
305 static void fxp_internal_error(char *msg
)
307 fxp_error_message
= msg
;
311 const char *fxp_error(void)
313 return fxp_error_message
;
316 int fxp_error_type(void)
322 * Perform exchange of init/version packets. Return 0 on failure.
326 struct sftp_packet
*pktout
, *pktin
;
329 pktout
= sftp_pkt_init(SSH_FXP_INIT
);
330 sftp_pkt_adduint32(pktout
, SFTP_PROTO_VERSION
);
335 fxp_internal_error("could not connect");
338 if (pktin
->type
!= SSH_FXP_VERSION
) {
339 fxp_internal_error("did not receive FXP_VERSION");
342 remotever
= sftp_pkt_getuint32(pktin
);
343 if (remotever
> SFTP_PROTO_VERSION
) {
345 ("remote protocol is more advanced than we support");
349 * In principle, this packet might also contain extension-
350 * string pairs. We should work through them and look for any
351 * we recognise. In practice we don't currently do so because
352 * we know we don't recognise _any_.
354 sftp_pkt_free(pktin
);
360 * Canonify a pathname.
362 char *fxp_realpath(char *path
)
364 struct sftp_packet
*pktin
, *pktout
;
367 pktout
= sftp_pkt_init(SSH_FXP_REALPATH
);
368 sftp_pkt_adduint32(pktout
, 0x123); /* request id */
369 sftp_pkt_addstring_start(pktout
);
370 sftp_pkt_addstring_str(pktout
, path
);
374 fxp_internal_error("did not receive a valid SFTP packet\n");
377 id
= sftp_pkt_getuint32(pktin
);
379 fxp_internal_error("request ID mismatch\n");
382 if (pktin
->type
== SSH_FXP_NAME
) {
387 count
= sftp_pkt_getuint32(pktin
);
389 fxp_internal_error("REALPATH returned name count != 1\n");
392 sftp_pkt_getstring(pktin
, &path
, &len
);
394 fxp_internal_error("REALPATH returned malformed FXP_NAME\n");
397 path
= mkstr(path
, len
);
398 sftp_pkt_free(pktin
);
401 fxp_got_status(pktin
);
409 struct fxp_handle
*fxp_open(char *path
, int type
)
411 struct sftp_packet
*pktin
, *pktout
;
414 pktout
= sftp_pkt_init(SSH_FXP_OPEN
);
415 sftp_pkt_adduint32(pktout
, 0x567); /* request id */
416 sftp_pkt_addstring(pktout
, path
);
417 sftp_pkt_adduint32(pktout
, type
);
418 sftp_pkt_adduint32(pktout
, 0); /* (FIXME) empty ATTRS structure */
422 fxp_internal_error("did not receive a valid SFTP packet\n");
425 id
= sftp_pkt_getuint32(pktin
);
427 fxp_internal_error("request ID mismatch\n");
430 if (pktin
->type
== SSH_FXP_HANDLE
) {
432 struct fxp_handle
*handle
;
435 sftp_pkt_getstring(pktin
, &hstring
, &len
);
437 fxp_internal_error("OPEN returned malformed FXP_HANDLE\n");
440 handle
= smalloc(sizeof(struct fxp_handle
));
441 handle
->hstring
= mkstr(hstring
, len
);
443 sftp_pkt_free(pktin
);
446 fxp_got_status(pktin
);
454 struct fxp_handle
*fxp_opendir(char *path
)
456 struct sftp_packet
*pktin
, *pktout
;
459 pktout
= sftp_pkt_init(SSH_FXP_OPENDIR
);
460 sftp_pkt_adduint32(pktout
, 0x456); /* request id */
461 sftp_pkt_addstring(pktout
, path
);
465 fxp_internal_error("did not receive a valid SFTP packet\n");
468 id
= sftp_pkt_getuint32(pktin
);
470 fxp_internal_error("request ID mismatch\n");
473 if (pktin
->type
== SSH_FXP_HANDLE
) {
475 struct fxp_handle
*handle
;
478 sftp_pkt_getstring(pktin
, &hstring
, &len
);
480 fxp_internal_error("OPENDIR returned malformed FXP_HANDLE\n");
483 handle
= smalloc(sizeof(struct fxp_handle
));
484 handle
->hstring
= mkstr(hstring
, len
);
486 sftp_pkt_free(pktin
);
489 fxp_got_status(pktin
);
497 void fxp_close(struct fxp_handle
*handle
)
499 struct sftp_packet
*pktin
, *pktout
;
502 pktout
= sftp_pkt_init(SSH_FXP_CLOSE
);
503 sftp_pkt_adduint32(pktout
, 0x789); /* request id */
504 sftp_pkt_addstring_start(pktout
);
505 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
509 fxp_internal_error("did not receive a valid SFTP packet\n");
512 id
= sftp_pkt_getuint32(pktin
);
514 fxp_internal_error("request ID mismatch\n");
517 fxp_got_status(pktin
);
518 sfree(handle
->hstring
);
522 int fxp_mkdir(char *path
)
524 struct sftp_packet
*pktin
, *pktout
;
527 pktout
= sftp_pkt_init(SSH_FXP_MKDIR
);
528 sftp_pkt_adduint32(pktout
, 0x234); /* request id */
529 sftp_pkt_addstring(pktout
, path
);
530 sftp_pkt_adduint32(pktout
, 0); /* (FIXME) empty ATTRS structure */
534 fxp_internal_error("did not receive a valid SFTP packet\n");
537 id
= sftp_pkt_getuint32(pktin
);
539 fxp_internal_error("request ID mismatch\n");
542 id
= fxp_got_status(pktin
);
549 int fxp_rmdir(char *path
)
551 struct sftp_packet
*pktin
, *pktout
;
554 pktout
= sftp_pkt_init(SSH_FXP_RMDIR
);
555 sftp_pkt_adduint32(pktout
, 0x345); /* request id */
556 sftp_pkt_addstring(pktout
, path
);
560 fxp_internal_error("did not receive a valid SFTP packet\n");
563 id
= sftp_pkt_getuint32(pktin
);
565 fxp_internal_error("request ID mismatch\n");
568 id
= fxp_got_status(pktin
);
575 int fxp_remove(char *fname
)
577 struct sftp_packet
*pktin
, *pktout
;
580 pktout
= sftp_pkt_init(SSH_FXP_REMOVE
);
581 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
582 sftp_pkt_addstring(pktout
, fname
);
586 fxp_internal_error("did not receive a valid SFTP packet\n");
589 id
= sftp_pkt_getuint32(pktin
);
591 fxp_internal_error("request ID mismatch\n");
594 id
= fxp_got_status(pktin
);
601 int fxp_rename(char *srcfname
, char *dstfname
)
603 struct sftp_packet
*pktin
, *pktout
;
606 pktout
= sftp_pkt_init(SSH_FXP_RENAME
);
607 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
608 sftp_pkt_addstring(pktout
, srcfname
);
609 sftp_pkt_addstring(pktout
, dstfname
);
613 fxp_internal_error("did not receive a valid SFTP packet\n");
616 id
= sftp_pkt_getuint32(pktin
);
618 fxp_internal_error("request ID mismatch\n");
621 id
= fxp_got_status(pktin
);
629 * Retrieve the attributes of a file. We have fxp_stat which works
630 * on filenames, and fxp_fstat which works on open file handles.
632 int fxp_stat(char *fname
, struct fxp_attrs
*attrs
)
634 struct sftp_packet
*pktin
, *pktout
;
637 pktout
= sftp_pkt_init(SSH_FXP_STAT
);
638 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
639 sftp_pkt_addstring(pktout
, fname
);
643 fxp_internal_error("did not receive a valid SFTP packet\n");
646 id
= sftp_pkt_getuint32(pktin
);
648 fxp_internal_error("request ID mismatch\n");
652 if (pktin
->type
== SSH_FXP_ATTRS
) {
653 *attrs
= sftp_pkt_getattrs(pktin
);
656 fxp_got_status(pktin
);
661 int fxp_fstat(struct fxp_handle
*handle
, struct fxp_attrs
*attrs
)
663 struct sftp_packet
*pktin
, *pktout
;
666 pktout
= sftp_pkt_init(SSH_FXP_FSTAT
);
667 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
668 sftp_pkt_addstring_start(pktout
);
669 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
673 fxp_internal_error("did not receive a valid SFTP packet\n");
676 id
= sftp_pkt_getuint32(pktin
);
678 fxp_internal_error("request ID mismatch\n");
682 if (pktin
->type
== SSH_FXP_ATTRS
) {
683 *attrs
= sftp_pkt_getattrs(pktin
);
686 fxp_got_status(pktin
);
692 * Set the attributes of a file.
694 int fxp_setstat(char *fname
, struct fxp_attrs attrs
)
696 struct sftp_packet
*pktin
, *pktout
;
699 pktout
= sftp_pkt_init(SSH_FXP_SETSTAT
);
700 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
701 sftp_pkt_addstring(pktout
, fname
);
702 sftp_pkt_addattrs(pktout
, attrs
);
706 fxp_internal_error("did not receive a valid SFTP packet\n");
709 id
= sftp_pkt_getuint32(pktin
);
711 fxp_internal_error("request ID mismatch\n");
714 id
= fxp_got_status(pktin
);
720 int fxp_fsetstat(struct fxp_handle
*handle
, struct fxp_attrs attrs
)
722 struct sftp_packet
*pktin
, *pktout
;
725 pktout
= sftp_pkt_init(SSH_FXP_FSETSTAT
);
726 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
727 sftp_pkt_addstring_start(pktout
);
728 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
729 sftp_pkt_addattrs(pktout
, attrs
);
733 fxp_internal_error("did not receive a valid SFTP packet\n");
736 id
= sftp_pkt_getuint32(pktin
);
738 fxp_internal_error("request ID mismatch\n");
741 id
= fxp_got_status(pktin
);
749 * Read from a file. Returns the number of bytes read, or -1 on an
750 * error, or possibly 0 if EOF. (I'm not entirely sure whether it
751 * will return 0 on EOF, or return -1 and store SSH_FX_EOF in the
752 * error indicator. It might even depend on the SFTP server.)
754 int fxp_read(struct fxp_handle
*handle
, char *buffer
, uint64 offset
,
757 struct sftp_packet
*pktin
, *pktout
;
760 pktout
= sftp_pkt_init(SSH_FXP_READ
);
761 sftp_pkt_adduint32(pktout
, 0xBCD); /* request id */
762 sftp_pkt_addstring_start(pktout
);
763 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
764 sftp_pkt_adduint64(pktout
, offset
);
765 sftp_pkt_adduint32(pktout
, len
);
769 fxp_internal_error("did not receive a valid SFTP packet\n");
772 id
= sftp_pkt_getuint32(pktin
);
774 fxp_internal_error("request ID mismatch");
777 if (pktin
->type
== SSH_FXP_DATA
) {
781 sftp_pkt_getstring(pktin
, &str
, &rlen
);
783 if (rlen
> len
|| rlen
< 0) {
784 fxp_internal_error("READ returned more bytes than requested");
788 memcpy(buffer
, str
, rlen
);
792 fxp_got_status(pktin
);
798 * Read from a directory.
800 struct fxp_names
*fxp_readdir(struct fxp_handle
*handle
)
802 struct sftp_packet
*pktin
, *pktout
;
805 pktout
= sftp_pkt_init(SSH_FXP_READDIR
);
806 sftp_pkt_adduint32(pktout
, 0xABC); /* request id */
807 sftp_pkt_addstring_start(pktout
);
808 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
812 fxp_internal_error("did not receive a valid SFTP packet\n");
815 id
= sftp_pkt_getuint32(pktin
);
817 fxp_internal_error("request ID mismatch\n");
820 if (pktin
->type
== SSH_FXP_NAME
) {
821 struct fxp_names
*ret
;
823 ret
= smalloc(sizeof(struct fxp_names
));
824 ret
->nnames
= sftp_pkt_getuint32(pktin
);
825 ret
->names
= smalloc(ret
->nnames
* sizeof(struct fxp_name
));
826 for (i
= 0; i
< ret
->nnames
; i
++) {
829 sftp_pkt_getstring(pktin
, &str
, &len
);
830 ret
->names
[i
].filename
= mkstr(str
, len
);
831 sftp_pkt_getstring(pktin
, &str
, &len
);
832 ret
->names
[i
].longname
= mkstr(str
, len
);
833 ret
->names
[i
].attrs
= sftp_pkt_getattrs(pktin
);
837 fxp_got_status(pktin
);
843 * Write to a file. Returns 0 on error, 1 on OK.
845 int fxp_write(struct fxp_handle
*handle
, char *buffer
, uint64 offset
,
848 struct sftp_packet
*pktin
, *pktout
;
851 pktout
= sftp_pkt_init(SSH_FXP_WRITE
);
852 sftp_pkt_adduint32(pktout
, 0xDCB); /* request id */
853 sftp_pkt_addstring_start(pktout
);
854 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
855 sftp_pkt_adduint64(pktout
, offset
);
856 sftp_pkt_addstring_start(pktout
);
857 sftp_pkt_addstring_data(pktout
, buffer
, len
);
861 fxp_internal_error("did not receive a valid SFTP packet\n");
864 id
= sftp_pkt_getuint32(pktin
);
866 fxp_internal_error("request ID mismatch\n");
869 fxp_got_status(pktin
);
870 return fxp_errtype
== SSH_FX_OK
;
874 * Free up an fxp_names structure.
876 void fxp_free_names(struct fxp_names
*names
)
880 for (i
= 0; i
< names
->nnames
; i
++) {
881 sfree(names
->names
[i
].filename
);
882 sfree(names
->names
[i
].longname
);