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
);
373 id
= sftp_pkt_getuint32(pktin
);
375 fxp_internal_error("request ID mismatch\n");
378 if (pktin
->type
== SSH_FXP_NAME
) {
383 count
= sftp_pkt_getuint32(pktin
);
385 fxp_internal_error("REALPATH returned name count != 1\n");
388 sftp_pkt_getstring(pktin
, &path
, &len
);
390 fxp_internal_error("REALPATH returned malformed FXP_NAME\n");
393 path
= mkstr(path
, len
);
394 sftp_pkt_free(pktin
);
397 fxp_got_status(pktin
);
405 struct fxp_handle
*fxp_open(char *path
, int type
)
407 struct sftp_packet
*pktin
, *pktout
;
410 pktout
= sftp_pkt_init(SSH_FXP_OPEN
);
411 sftp_pkt_adduint32(pktout
, 0x567); /* request id */
412 sftp_pkt_addstring(pktout
, path
);
413 sftp_pkt_adduint32(pktout
, type
);
414 sftp_pkt_adduint32(pktout
, 0); /* (FIXME) empty ATTRS structure */
417 id
= sftp_pkt_getuint32(pktin
);
419 fxp_internal_error("request ID mismatch\n");
422 if (pktin
->type
== SSH_FXP_HANDLE
) {
424 struct fxp_handle
*handle
;
427 sftp_pkt_getstring(pktin
, &hstring
, &len
);
429 fxp_internal_error("OPEN returned malformed FXP_HANDLE\n");
432 handle
= smalloc(sizeof(struct fxp_handle
));
433 handle
->hstring
= mkstr(hstring
, len
);
435 sftp_pkt_free(pktin
);
438 fxp_got_status(pktin
);
446 struct fxp_handle
*fxp_opendir(char *path
)
448 struct sftp_packet
*pktin
, *pktout
;
451 pktout
= sftp_pkt_init(SSH_FXP_OPENDIR
);
452 sftp_pkt_adduint32(pktout
, 0x456); /* request id */
453 sftp_pkt_addstring(pktout
, path
);
456 id
= sftp_pkt_getuint32(pktin
);
458 fxp_internal_error("request ID mismatch\n");
461 if (pktin
->type
== SSH_FXP_HANDLE
) {
463 struct fxp_handle
*handle
;
466 sftp_pkt_getstring(pktin
, &hstring
, &len
);
468 fxp_internal_error("OPENDIR returned malformed FXP_HANDLE\n");
471 handle
= smalloc(sizeof(struct fxp_handle
));
472 handle
->hstring
= mkstr(hstring
, len
);
474 sftp_pkt_free(pktin
);
477 fxp_got_status(pktin
);
485 void fxp_close(struct fxp_handle
*handle
)
487 struct sftp_packet
*pktin
, *pktout
;
490 pktout
= sftp_pkt_init(SSH_FXP_CLOSE
);
491 sftp_pkt_adduint32(pktout
, 0x789); /* request id */
492 sftp_pkt_addstring_start(pktout
);
493 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
496 id
= sftp_pkt_getuint32(pktin
);
498 fxp_internal_error("request ID mismatch\n");
501 fxp_got_status(pktin
);
502 sfree(handle
->hstring
);
506 int fxp_mkdir(char *path
)
508 struct sftp_packet
*pktin
, *pktout
;
511 pktout
= sftp_pkt_init(SSH_FXP_MKDIR
);
512 sftp_pkt_adduint32(pktout
, 0x234); /* request id */
513 sftp_pkt_addstring(pktout
, path
);
514 sftp_pkt_adduint32(pktout
, 0); /* (FIXME) empty ATTRS structure */
517 id
= sftp_pkt_getuint32(pktin
);
519 fxp_internal_error("request ID mismatch\n");
522 id
= fxp_got_status(pktin
);
529 int fxp_rmdir(char *path
)
531 struct sftp_packet
*pktin
, *pktout
;
534 pktout
= sftp_pkt_init(SSH_FXP_RMDIR
);
535 sftp_pkt_adduint32(pktout
, 0x345); /* request id */
536 sftp_pkt_addstring(pktout
, path
);
539 id
= sftp_pkt_getuint32(pktin
);
541 fxp_internal_error("request ID mismatch\n");
544 id
= fxp_got_status(pktin
);
551 int fxp_remove(char *fname
)
553 struct sftp_packet
*pktin
, *pktout
;
556 pktout
= sftp_pkt_init(SSH_FXP_REMOVE
);
557 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
558 sftp_pkt_addstring(pktout
, fname
);
561 id
= sftp_pkt_getuint32(pktin
);
563 fxp_internal_error("request ID mismatch\n");
566 id
= fxp_got_status(pktin
);
573 int fxp_rename(char *srcfname
, char *dstfname
)
575 struct sftp_packet
*pktin
, *pktout
;
578 pktout
= sftp_pkt_init(SSH_FXP_RENAME
);
579 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
580 sftp_pkt_addstring(pktout
, srcfname
);
581 sftp_pkt_addstring(pktout
, dstfname
);
584 id
= sftp_pkt_getuint32(pktin
);
586 fxp_internal_error("request ID mismatch\n");
589 id
= fxp_got_status(pktin
);
597 * Retrieve the attributes of a file. We have fxp_stat which works
598 * on filenames, and fxp_fstat which works on open file handles.
600 int fxp_stat(char *fname
, struct fxp_attrs
*attrs
)
602 struct sftp_packet
*pktin
, *pktout
;
605 pktout
= sftp_pkt_init(SSH_FXP_STAT
);
606 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
607 sftp_pkt_addstring(pktout
, fname
);
610 id
= sftp_pkt_getuint32(pktin
);
612 fxp_internal_error("request ID mismatch\n");
616 if (pktin
->type
== SSH_FXP_ATTRS
) {
617 *attrs
= sftp_pkt_getattrs(pktin
);
620 fxp_got_status(pktin
);
625 int fxp_fstat(struct fxp_handle
*handle
, struct fxp_attrs
*attrs
)
627 struct sftp_packet
*pktin
, *pktout
;
630 pktout
= sftp_pkt_init(SSH_FXP_FSTAT
);
631 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
632 sftp_pkt_addstring_start(pktout
);
633 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
636 id
= sftp_pkt_getuint32(pktin
);
638 fxp_internal_error("request ID mismatch\n");
642 if (pktin
->type
== SSH_FXP_ATTRS
) {
643 *attrs
= sftp_pkt_getattrs(pktin
);
646 fxp_got_status(pktin
);
652 * Set the attributes of a file.
654 int fxp_setstat(char *fname
, struct fxp_attrs attrs
)
656 struct sftp_packet
*pktin
, *pktout
;
659 pktout
= sftp_pkt_init(SSH_FXP_SETSTAT
);
660 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
661 sftp_pkt_addstring(pktout
, fname
);
662 sftp_pkt_addattrs(pktout
, attrs
);
665 id
= sftp_pkt_getuint32(pktin
);
667 fxp_internal_error("request ID mismatch\n");
670 id
= fxp_got_status(pktin
);
676 int fxp_fsetstat(struct fxp_handle
*handle
, struct fxp_attrs attrs
)
678 struct sftp_packet
*pktin
, *pktout
;
681 pktout
= sftp_pkt_init(SSH_FXP_FSETSTAT
);
682 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
683 sftp_pkt_addstring_start(pktout
);
684 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
685 sftp_pkt_addattrs(pktout
, attrs
);
688 id
= sftp_pkt_getuint32(pktin
);
690 fxp_internal_error("request ID mismatch\n");
693 id
= fxp_got_status(pktin
);
701 * Read from a file. Returns the number of bytes read, or -1 on an
702 * error, or possibly 0 if EOF. (I'm not entirely sure whether it
703 * will return 0 on EOF, or return -1 and store SSH_FX_EOF in the
704 * error indicator. It might even depend on the SFTP server.)
706 int fxp_read(struct fxp_handle
*handle
, char *buffer
, uint64 offset
,
709 struct sftp_packet
*pktin
, *pktout
;
712 pktout
= sftp_pkt_init(SSH_FXP_READ
);
713 sftp_pkt_adduint32(pktout
, 0xBCD); /* request id */
714 sftp_pkt_addstring_start(pktout
);
715 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
716 sftp_pkt_adduint64(pktout
, offset
);
717 sftp_pkt_adduint32(pktout
, len
);
720 id
= sftp_pkt_getuint32(pktin
);
722 fxp_internal_error("request ID mismatch");
725 if (pktin
->type
== SSH_FXP_DATA
) {
729 sftp_pkt_getstring(pktin
, &str
, &rlen
);
731 if (rlen
> len
|| rlen
< 0) {
732 fxp_internal_error("READ returned more bytes than requested");
736 memcpy(buffer
, str
, rlen
);
740 fxp_got_status(pktin
);
746 * Read from a directory.
748 struct fxp_names
*fxp_readdir(struct fxp_handle
*handle
)
750 struct sftp_packet
*pktin
, *pktout
;
753 pktout
= sftp_pkt_init(SSH_FXP_READDIR
);
754 sftp_pkt_adduint32(pktout
, 0xABC); /* request id */
755 sftp_pkt_addstring_start(pktout
);
756 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
759 id
= sftp_pkt_getuint32(pktin
);
761 fxp_internal_error("request ID mismatch\n");
764 if (pktin
->type
== SSH_FXP_NAME
) {
765 struct fxp_names
*ret
;
767 ret
= smalloc(sizeof(struct fxp_names
));
768 ret
->nnames
= sftp_pkt_getuint32(pktin
);
769 ret
->names
= smalloc(ret
->nnames
* sizeof(struct fxp_name
));
770 for (i
= 0; i
< ret
->nnames
; i
++) {
773 sftp_pkt_getstring(pktin
, &str
, &len
);
774 ret
->names
[i
].filename
= mkstr(str
, len
);
775 sftp_pkt_getstring(pktin
, &str
, &len
);
776 ret
->names
[i
].longname
= mkstr(str
, len
);
777 ret
->names
[i
].attrs
= sftp_pkt_getattrs(pktin
);
781 fxp_got_status(pktin
);
787 * Write to a file. Returns 0 on error, 1 on OK.
789 int fxp_write(struct fxp_handle
*handle
, char *buffer
, uint64 offset
,
792 struct sftp_packet
*pktin
, *pktout
;
795 pktout
= sftp_pkt_init(SSH_FXP_WRITE
);
796 sftp_pkt_adduint32(pktout
, 0xDCB); /* request id */
797 sftp_pkt_addstring_start(pktout
);
798 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
799 sftp_pkt_adduint64(pktout
, offset
);
800 sftp_pkt_addstring_start(pktout
);
801 sftp_pkt_addstring_data(pktout
, buffer
, len
);
804 id
= sftp_pkt_getuint32(pktin
);
806 fxp_internal_error("request ID mismatch\n");
809 fxp_got_status(pktin
);
810 return fxp_errtype
== SSH_FX_OK
;
814 * Free up an fxp_names structure.
816 void fxp_free_names(struct fxp_names
*names
)
820 for (i
= 0; i
< names
->nnames
; i
++) {
821 sfree(names
->names
[i
].filename
);
822 sfree(names
->names
[i
].longname
);