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
);
67 static void sftp_pkt_addbool(struct sftp_packet
*pkt
, unsigned char value
)
69 sftp_pkt_adddata(pkt
, &value
, 1);
71 static void sftp_pkt_adduint32(struct sftp_packet
*pkt
,
76 sftp_pkt_adddata(pkt
, x
, 4);
78 static void sftp_pkt_adduint64(struct sftp_packet
*pkt
, uint64 value
)
81 PUT_32BIT(x
, value
.hi
);
82 PUT_32BIT(x
+ 4, value
.lo
);
83 sftp_pkt_adddata(pkt
, x
, 8);
85 static void sftp_pkt_addstring_start(struct sftp_packet
*pkt
)
87 sftp_pkt_adduint32(pkt
, 0);
88 pkt
->savedpos
= pkt
->length
;
90 static void sftp_pkt_addstring_str(struct sftp_packet
*pkt
, char *data
)
92 sftp_pkt_adddata(pkt
, data
, strlen(data
));
93 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
95 static void sftp_pkt_addstring_data(struct sftp_packet
*pkt
,
98 sftp_pkt_adddata(pkt
, data
, len
);
99 PUT_32BIT(pkt
->data
+ pkt
->savedpos
- 4, pkt
->length
- pkt
->savedpos
);
101 static void sftp_pkt_addstring(struct sftp_packet
*pkt
, char *data
)
103 sftp_pkt_addstring_start(pkt
);
104 sftp_pkt_addstring_str(pkt
, data
);
106 static void sftp_pkt_addattrs(struct sftp_packet
*pkt
, struct fxp_attrs attrs
)
108 sftp_pkt_adduint32(pkt
, attrs
.flags
);
109 if (attrs
.flags
& SSH_FILEXFER_ATTR_SIZE
) {
110 sftp_pkt_adduint32(pkt
, attrs
.size
.hi
);
111 sftp_pkt_adduint32(pkt
, attrs
.size
.lo
);
113 if (attrs
.flags
& SSH_FILEXFER_ATTR_UIDGID
) {
114 sftp_pkt_adduint32(pkt
, attrs
.uid
);
115 sftp_pkt_adduint32(pkt
, attrs
.gid
);
117 if (attrs
.flags
& SSH_FILEXFER_ATTR_PERMISSIONS
) {
118 sftp_pkt_adduint32(pkt
, attrs
.permissions
);
120 if (attrs
.flags
& SSH_FILEXFER_ATTR_ACMODTIME
) {
121 sftp_pkt_adduint32(pkt
, attrs
.atime
);
122 sftp_pkt_adduint32(pkt
, attrs
.mtime
);
124 if (attrs
.flags
& SSH_FILEXFER_ATTR_EXTENDED
) {
126 * We currently don't support sending any extended
132 /* ----------------------------------------------------------------------
133 * SFTP packet decode functions.
136 static unsigned char sftp_pkt_getbyte(struct sftp_packet
*pkt
)
139 if (pkt
->length
- pkt
->savedpos
< 1)
140 return 0; /* arrgh, no way to decline (FIXME?) */
141 value
= (unsigned char) pkt
->data
[pkt
->savedpos
];
145 static unsigned long sftp_pkt_getuint32(struct sftp_packet
*pkt
)
148 if (pkt
->length
- pkt
->savedpos
< 4)
149 return 0; /* arrgh, no way to decline (FIXME?) */
150 value
= GET_32BIT(pkt
->data
+ pkt
->savedpos
);
154 static void sftp_pkt_getstring(struct sftp_packet
*pkt
,
155 char **p
, int *length
)
158 if (pkt
->length
- pkt
->savedpos
< 4)
160 *length
= GET_32BIT(pkt
->data
+ pkt
->savedpos
);
162 if (pkt
->length
- pkt
->savedpos
< *length
)
164 *p
= pkt
->data
+ pkt
->savedpos
;
165 pkt
->savedpos
+= *length
;
167 static struct fxp_attrs
sftp_pkt_getattrs(struct sftp_packet
*pkt
)
169 struct fxp_attrs ret
;
170 ret
.flags
= sftp_pkt_getuint32(pkt
);
171 if (ret
.flags
& SSH_FILEXFER_ATTR_SIZE
) {
172 unsigned long hi
, lo
;
173 hi
= sftp_pkt_getuint32(pkt
);
174 lo
= sftp_pkt_getuint32(pkt
);
175 ret
.size
= uint64_make(hi
, lo
);
177 if (ret
.flags
& SSH_FILEXFER_ATTR_UIDGID
) {
178 ret
.uid
= sftp_pkt_getuint32(pkt
);
179 ret
.gid
= sftp_pkt_getuint32(pkt
);
181 if (ret
.flags
& SSH_FILEXFER_ATTR_PERMISSIONS
) {
182 ret
.permissions
= sftp_pkt_getuint32(pkt
);
184 if (ret
.flags
& SSH_FILEXFER_ATTR_ACMODTIME
) {
185 ret
.atime
= sftp_pkt_getuint32(pkt
);
186 ret
.mtime
= sftp_pkt_getuint32(pkt
);
188 if (ret
.flags
& SSH_FILEXFER_ATTR_EXTENDED
) {
190 count
= sftp_pkt_getuint32(pkt
);
195 * We should try to analyse these, if we ever find one
198 sftp_pkt_getstring(pkt
, &str
, &len
);
199 sftp_pkt_getstring(pkt
, &str
, &len
);
204 static void sftp_pkt_free(struct sftp_packet
*pkt
)
211 /* ----------------------------------------------------------------------
212 * Send and receive packet functions.
214 int sftp_send(struct sftp_packet
*pkt
)
218 PUT_32BIT(x
, pkt
->length
);
219 ret
= (sftp_senddata(x
, 4) && sftp_senddata(pkt
->data
, pkt
->length
));
223 struct sftp_packet
*sftp_recv(void)
225 struct sftp_packet
*pkt
;
228 if (!sftp_recvdata(x
, 4))
231 pkt
= smalloc(sizeof(struct sftp_packet
));
233 pkt
->length
= pkt
->maxlen
= GET_32BIT(x
);
234 pkt
->data
= smalloc(pkt
->length
);
236 if (!sftp_recvdata(pkt
->data
, pkt
->length
)) {
241 pkt
->type
= sftp_pkt_getbyte(pkt
);
246 /* ----------------------------------------------------------------------
247 * String handling routines.
250 static char *mkstr(char *s
, int len
)
252 char *p
= smalloc(len
+ 1);
258 /* ----------------------------------------------------------------------
263 * Deal with (and free) an FXP_STATUS packet. Return 1 if
264 * SSH_FX_OK, 0 if SSH_FX_EOF, and -1 for anything else (error).
265 * Also place the status into fxp_errtype.
267 static int fxp_got_status(struct sftp_packet
*pktin
)
269 static const char *const messages
[] = {
270 /* SSH_FX_OK. The only time we will display a _message_ for this
271 * is if we were expecting something other than FXP_STATUS on
272 * success, so this is actually an error message! */
273 "unexpected OK response",
275 "no such file or directory",
281 "operation unsupported",
284 if (pktin
->type
!= SSH_FXP_STATUS
) {
285 fxp_error_message
= "expected FXP_STATUS packet";
288 fxp_errtype
= sftp_pkt_getuint32(pktin
);
289 if (fxp_errtype
< 0 ||
290 fxp_errtype
>= sizeof(messages
) / sizeof(*messages
))
291 fxp_error_message
= "unknown error code";
293 fxp_error_message
= messages
[fxp_errtype
];
296 if (fxp_errtype
== SSH_FX_OK
)
298 else if (fxp_errtype
== SSH_FX_EOF
)
304 static void fxp_internal_error(char *msg
)
306 fxp_error_message
= msg
;
310 const char *fxp_error(void)
312 return fxp_error_message
;
315 int fxp_error_type(void)
321 * Perform exchange of init/version packets. Return 0 on failure.
325 struct sftp_packet
*pktout
, *pktin
;
328 pktout
= sftp_pkt_init(SSH_FXP_INIT
);
329 sftp_pkt_adduint32(pktout
, SFTP_PROTO_VERSION
);
334 fxp_internal_error("could not connect");
337 if (pktin
->type
!= SSH_FXP_VERSION
) {
338 fxp_internal_error("did not receive FXP_VERSION");
341 remotever
= sftp_pkt_getuint32(pktin
);
342 if (remotever
> SFTP_PROTO_VERSION
) {
344 ("remote protocol is more advanced than we support");
348 * In principle, this packet might also contain extension-
349 * string pairs. We should work through them and look for any
350 * we recognise. In practice we don't currently do so because
351 * we know we don't recognise _any_.
353 sftp_pkt_free(pktin
);
359 * Canonify a pathname.
361 char *fxp_realpath(char *path
)
363 struct sftp_packet
*pktin
, *pktout
;
366 pktout
= sftp_pkt_init(SSH_FXP_REALPATH
);
367 sftp_pkt_adduint32(pktout
, 0x123); /* request id */
368 sftp_pkt_addstring_start(pktout
);
369 sftp_pkt_addstring_str(pktout
, path
);
373 fxp_internal_error("did not receive a valid SFTP packet\n");
376 id
= sftp_pkt_getuint32(pktin
);
378 fxp_internal_error("request ID mismatch\n");
381 if (pktin
->type
== SSH_FXP_NAME
) {
386 count
= sftp_pkt_getuint32(pktin
);
388 fxp_internal_error("REALPATH returned name count != 1\n");
391 sftp_pkt_getstring(pktin
, &path
, &len
);
393 fxp_internal_error("REALPATH returned malformed FXP_NAME\n");
396 path
= mkstr(path
, len
);
397 sftp_pkt_free(pktin
);
400 fxp_got_status(pktin
);
408 struct fxp_handle
*fxp_open(char *path
, int type
)
410 struct sftp_packet
*pktin
, *pktout
;
413 pktout
= sftp_pkt_init(SSH_FXP_OPEN
);
414 sftp_pkt_adduint32(pktout
, 0x567); /* request id */
415 sftp_pkt_addstring(pktout
, path
);
416 sftp_pkt_adduint32(pktout
, type
);
417 sftp_pkt_adduint32(pktout
, 0); /* (FIXME) empty ATTRS structure */
421 fxp_internal_error("did not receive a valid SFTP packet\n");
424 id
= sftp_pkt_getuint32(pktin
);
426 fxp_internal_error("request ID mismatch\n");
429 if (pktin
->type
== SSH_FXP_HANDLE
) {
431 struct fxp_handle
*handle
;
434 sftp_pkt_getstring(pktin
, &hstring
, &len
);
436 fxp_internal_error("OPEN returned malformed FXP_HANDLE\n");
439 handle
= smalloc(sizeof(struct fxp_handle
));
440 handle
->hstring
= mkstr(hstring
, len
);
442 sftp_pkt_free(pktin
);
445 fxp_got_status(pktin
);
453 struct fxp_handle
*fxp_opendir(char *path
)
455 struct sftp_packet
*pktin
, *pktout
;
458 pktout
= sftp_pkt_init(SSH_FXP_OPENDIR
);
459 sftp_pkt_adduint32(pktout
, 0x456); /* request id */
460 sftp_pkt_addstring(pktout
, path
);
464 fxp_internal_error("did not receive a valid SFTP packet\n");
467 id
= sftp_pkt_getuint32(pktin
);
469 fxp_internal_error("request ID mismatch\n");
472 if (pktin
->type
== SSH_FXP_HANDLE
) {
474 struct fxp_handle
*handle
;
477 sftp_pkt_getstring(pktin
, &hstring
, &len
);
479 fxp_internal_error("OPENDIR returned malformed FXP_HANDLE\n");
482 handle
= smalloc(sizeof(struct fxp_handle
));
483 handle
->hstring
= mkstr(hstring
, len
);
485 sftp_pkt_free(pktin
);
488 fxp_got_status(pktin
);
496 void fxp_close(struct fxp_handle
*handle
)
498 struct sftp_packet
*pktin
, *pktout
;
501 pktout
= sftp_pkt_init(SSH_FXP_CLOSE
);
502 sftp_pkt_adduint32(pktout
, 0x789); /* request id */
503 sftp_pkt_addstring_start(pktout
);
504 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
508 fxp_internal_error("did not receive a valid SFTP packet\n");
511 id
= sftp_pkt_getuint32(pktin
);
513 fxp_internal_error("request ID mismatch\n");
516 fxp_got_status(pktin
);
517 sfree(handle
->hstring
);
521 int fxp_mkdir(char *path
)
523 struct sftp_packet
*pktin
, *pktout
;
526 pktout
= sftp_pkt_init(SSH_FXP_MKDIR
);
527 sftp_pkt_adduint32(pktout
, 0x234); /* request id */
528 sftp_pkt_addstring(pktout
, path
);
529 sftp_pkt_adduint32(pktout
, 0); /* (FIXME) empty ATTRS structure */
533 fxp_internal_error("did not receive a valid SFTP packet\n");
536 id
= sftp_pkt_getuint32(pktin
);
538 fxp_internal_error("request ID mismatch\n");
541 id
= fxp_got_status(pktin
);
548 int fxp_rmdir(char *path
)
550 struct sftp_packet
*pktin
, *pktout
;
553 pktout
= sftp_pkt_init(SSH_FXP_RMDIR
);
554 sftp_pkt_adduint32(pktout
, 0x345); /* request id */
555 sftp_pkt_addstring(pktout
, path
);
559 fxp_internal_error("did not receive a valid SFTP packet\n");
562 id
= sftp_pkt_getuint32(pktin
);
564 fxp_internal_error("request ID mismatch\n");
567 id
= fxp_got_status(pktin
);
574 int fxp_remove(char *fname
)
576 struct sftp_packet
*pktin
, *pktout
;
579 pktout
= sftp_pkt_init(SSH_FXP_REMOVE
);
580 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
581 sftp_pkt_addstring(pktout
, fname
);
585 fxp_internal_error("did not receive a valid SFTP packet\n");
588 id
= sftp_pkt_getuint32(pktin
);
590 fxp_internal_error("request ID mismatch\n");
593 id
= fxp_got_status(pktin
);
600 int fxp_rename(char *srcfname
, char *dstfname
)
602 struct sftp_packet
*pktin
, *pktout
;
605 pktout
= sftp_pkt_init(SSH_FXP_RENAME
);
606 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
607 sftp_pkt_addstring(pktout
, srcfname
);
608 sftp_pkt_addstring(pktout
, dstfname
);
612 fxp_internal_error("did not receive a valid SFTP packet\n");
615 id
= sftp_pkt_getuint32(pktin
);
617 fxp_internal_error("request ID mismatch\n");
620 id
= fxp_got_status(pktin
);
628 * Retrieve the attributes of a file. We have fxp_stat which works
629 * on filenames, and fxp_fstat which works on open file handles.
631 int fxp_stat(char *fname
, struct fxp_attrs
*attrs
)
633 struct sftp_packet
*pktin
, *pktout
;
636 pktout
= sftp_pkt_init(SSH_FXP_STAT
);
637 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
638 sftp_pkt_addstring(pktout
, fname
);
642 fxp_internal_error("did not receive a valid SFTP packet\n");
645 id
= sftp_pkt_getuint32(pktin
);
647 fxp_internal_error("request ID mismatch\n");
651 if (pktin
->type
== SSH_FXP_ATTRS
) {
652 *attrs
= sftp_pkt_getattrs(pktin
);
655 fxp_got_status(pktin
);
660 int fxp_fstat(struct fxp_handle
*handle
, struct fxp_attrs
*attrs
)
662 struct sftp_packet
*pktin
, *pktout
;
665 pktout
= sftp_pkt_init(SSH_FXP_FSTAT
);
666 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
667 sftp_pkt_addstring_start(pktout
);
668 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
672 fxp_internal_error("did not receive a valid SFTP packet\n");
675 id
= sftp_pkt_getuint32(pktin
);
677 fxp_internal_error("request ID mismatch\n");
681 if (pktin
->type
== SSH_FXP_ATTRS
) {
682 *attrs
= sftp_pkt_getattrs(pktin
);
685 fxp_got_status(pktin
);
691 * Set the attributes of a file.
693 int fxp_setstat(char *fname
, struct fxp_attrs attrs
)
695 struct sftp_packet
*pktin
, *pktout
;
698 pktout
= sftp_pkt_init(SSH_FXP_SETSTAT
);
699 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
700 sftp_pkt_addstring(pktout
, fname
);
701 sftp_pkt_addattrs(pktout
, attrs
);
705 fxp_internal_error("did not receive a valid SFTP packet\n");
708 id
= sftp_pkt_getuint32(pktin
);
710 fxp_internal_error("request ID mismatch\n");
713 id
= fxp_got_status(pktin
);
719 int fxp_fsetstat(struct fxp_handle
*handle
, struct fxp_attrs attrs
)
721 struct sftp_packet
*pktin
, *pktout
;
724 pktout
= sftp_pkt_init(SSH_FXP_FSETSTAT
);
725 sftp_pkt_adduint32(pktout
, 0x678); /* request id */
726 sftp_pkt_addstring_start(pktout
);
727 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
728 sftp_pkt_addattrs(pktout
, attrs
);
732 fxp_internal_error("did not receive a valid SFTP packet\n");
735 id
= sftp_pkt_getuint32(pktin
);
737 fxp_internal_error("request ID mismatch\n");
740 id
= fxp_got_status(pktin
);
748 * Read from a file. Returns the number of bytes read, or -1 on an
749 * error, or possibly 0 if EOF. (I'm not entirely sure whether it
750 * will return 0 on EOF, or return -1 and store SSH_FX_EOF in the
751 * error indicator. It might even depend on the SFTP server.)
753 int fxp_read(struct fxp_handle
*handle
, char *buffer
, uint64 offset
,
756 struct sftp_packet
*pktin
, *pktout
;
759 pktout
= sftp_pkt_init(SSH_FXP_READ
);
760 sftp_pkt_adduint32(pktout
, 0xBCD); /* request id */
761 sftp_pkt_addstring_start(pktout
);
762 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
763 sftp_pkt_adduint64(pktout
, offset
);
764 sftp_pkt_adduint32(pktout
, len
);
768 fxp_internal_error("did not receive a valid SFTP packet\n");
771 id
= sftp_pkt_getuint32(pktin
);
773 fxp_internal_error("request ID mismatch");
776 if (pktin
->type
== SSH_FXP_DATA
) {
780 sftp_pkt_getstring(pktin
, &str
, &rlen
);
782 if (rlen
> len
|| rlen
< 0) {
783 fxp_internal_error("READ returned more bytes than requested");
787 memcpy(buffer
, str
, rlen
);
791 fxp_got_status(pktin
);
797 * Read from a directory.
799 struct fxp_names
*fxp_readdir(struct fxp_handle
*handle
)
801 struct sftp_packet
*pktin
, *pktout
;
804 pktout
= sftp_pkt_init(SSH_FXP_READDIR
);
805 sftp_pkt_adduint32(pktout
, 0xABC); /* request id */
806 sftp_pkt_addstring_start(pktout
);
807 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
811 fxp_internal_error("did not receive a valid SFTP packet\n");
814 id
= sftp_pkt_getuint32(pktin
);
816 fxp_internal_error("request ID mismatch\n");
819 if (pktin
->type
== SSH_FXP_NAME
) {
820 struct fxp_names
*ret
;
822 ret
= smalloc(sizeof(struct fxp_names
));
823 ret
->nnames
= sftp_pkt_getuint32(pktin
);
824 ret
->names
= smalloc(ret
->nnames
* sizeof(struct fxp_name
));
825 for (i
= 0; i
< ret
->nnames
; i
++) {
828 sftp_pkt_getstring(pktin
, &str
, &len
);
829 ret
->names
[i
].filename
= mkstr(str
, len
);
830 sftp_pkt_getstring(pktin
, &str
, &len
);
831 ret
->names
[i
].longname
= mkstr(str
, len
);
832 ret
->names
[i
].attrs
= sftp_pkt_getattrs(pktin
);
836 fxp_got_status(pktin
);
842 * Write to a file. Returns 0 on error, 1 on OK.
844 int fxp_write(struct fxp_handle
*handle
, char *buffer
, uint64 offset
,
847 struct sftp_packet
*pktin
, *pktout
;
850 pktout
= sftp_pkt_init(SSH_FXP_WRITE
);
851 sftp_pkt_adduint32(pktout
, 0xDCB); /* request id */
852 sftp_pkt_addstring_start(pktout
);
853 sftp_pkt_addstring_data(pktout
, handle
->hstring
, handle
->hlen
);
854 sftp_pkt_adduint64(pktout
, offset
);
855 sftp_pkt_addstring_start(pktout
);
856 sftp_pkt_addstring_data(pktout
, buffer
, len
);
860 fxp_internal_error("did not receive a valid SFTP packet\n");
863 id
= sftp_pkt_getuint32(pktin
);
865 fxp_internal_error("request ID mismatch\n");
868 fxp_got_status(pktin
);
869 return fxp_errtype
== SSH_FX_OK
;
873 * Free up an fxp_names structure.
875 void fxp_free_names(struct fxp_names
*names
)
879 for (i
= 0; i
< names
->nnames
; i
++) {
880 sfree(names
->names
[i
].filename
);
881 sfree(names
->names
[i
].longname
);