1 /* $NetBSD: psbuf.c,v 1.19 2012/11/04 22:46:08 christos Exp $ */
2
3 /*
4 * Copyright (c) 2006-2009 Antti Kantee. All Rights Reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include <sys/cdefs.h>
29 #ifndef lint
30 __RCSID("$NetBSD: psbuf.c,v 1.19 2012/11/04 22:46:08 christos Exp $");
31 #endif /* !lint */
32
33 /*
34 * buffering functions for network input/output. slightly different
35 * from the average joe buffer routines, as is usually the case ...
36 * these use efuns for now.
37 */
38
39 #include <sys/types.h>
40 #include <sys/time.h>
41 #include <sys/vnode.h>
42 #include <sys/socket.h>
43
44 #include <err.h>
45 #include <errno.h>
46 #include <stdlib.h>
47 #include <util.h>
48 #include <unistd.h>
49
50 #include "psshfs.h"
51 #include "sftp_proto.h"
52
53 #define FAILRV(x) do { int rv; if ((rv=x)) return (rv); } while (/*CONSTCOND*/0)
54 #define READSTATE_LENGTH(off) (off < 4)
55
56 #define SFTP_LENOFF 0
57 #define SFTP_TYPEOFF 4
58 #define SFTP_REQIDOFF 5
59
60 #define CHECK(v) if (!(v)) abort()
61
62 uint8_t
psbuf_get_type(struct puffs_framebuf * pb)63 psbuf_get_type(struct puffs_framebuf *pb)
64 {
65 uint8_t type;
66
67 puffs_framebuf_getdata_atoff(pb, SFTP_TYPEOFF, &type, 1);
68 return type;
69 }
70
71 uint32_t
psbuf_get_len(struct puffs_framebuf * pb)72 psbuf_get_len(struct puffs_framebuf *pb)
73 {
74 uint32_t len;
75
76 puffs_framebuf_getdata_atoff(pb, SFTP_LENOFF, &len, 4);
77 return be32toh(len);
78 }
79
80 uint32_t
psbuf_get_reqid(struct puffs_framebuf * pb)81 psbuf_get_reqid(struct puffs_framebuf *pb)
82 {
83 uint32_t req;
84
85 puffs_framebuf_getdata_atoff(pb, SFTP_REQIDOFF, &req, 4);
86 return be32toh(req);
87 }
88
89 #define CUROFF(pb) (puffs_framebuf_telloff(pb))
90 int
psbuf_read(struct puffs_usermount * pu,struct puffs_framebuf * pb,int fd,int * done)91 psbuf_read(struct puffs_usermount *pu, struct puffs_framebuf *pb,
92 int fd, int *done)
93 {
94 void *win;
95 ssize_t n;
96 size_t howmuch, winlen;
97 int lenstate;
98
99 the_next_level:
100 if ((lenstate = READSTATE_LENGTH(CUROFF(pb))))
101 howmuch = 4 - CUROFF(pb);
102 else
103 howmuch = psbuf_get_len(pb) - (CUROFF(pb) - 4);
104
105 if (puffs_framebuf_reserve_space(pb, howmuch) == -1)
106 return errno;
107
108 while (howmuch) {
109 winlen = howmuch;
110 if (puffs_framebuf_getwindow(pb, CUROFF(pb), &win, &winlen)==-1)
111 return errno;
112 n = recv(fd, win, winlen, MSG_NOSIGNAL);
113 switch (n) {
114 case 0:
115 return ECONNRESET;
116 case -1:
117 if (errno == EAGAIN)
118 return 0;
119 return errno;
120 default:
121 howmuch -= n;
122 puffs_framebuf_seekset(pb, CUROFF(pb) + n);
123 break;
124 }
125 }
126
127 if (!lenstate) {
128 /* XXX: initial exchange shorter.. but don't worry, be happy */
129 puffs_framebuf_seekset(pb, 9);
130 *done = 1;
131 return 0;
132 } else
133 goto the_next_level;
134 }
135
136 int
psbuf_write(struct puffs_usermount * pu,struct puffs_framebuf * pb,int fd,int * done)137 psbuf_write(struct puffs_usermount *pu, struct puffs_framebuf *pb,
138 int fd, int *done)
139 {
140 void *win;
141 ssize_t n;
142 size_t winlen, howmuch;
143
144 /* finalize buffer.. could be elsewhere ... */
145 if (CUROFF(pb) == 0) {
146 uint32_t len;
147
148 len = htobe32(puffs_framebuf_tellsize(pb) - 4);
149 puffs_framebuf_putdata_atoff(pb, 0, &len, 4);
150 }
151
152 howmuch = puffs_framebuf_tellsize(pb) - CUROFF(pb);
153 while (howmuch) {
154 winlen = howmuch;
155 if (puffs_framebuf_getwindow(pb, CUROFF(pb), &win, &winlen)==-1)
156 return errno;
157 n = send(fd, win, winlen, MSG_NOSIGNAL);
158 switch (n) {
159 case 0:
160 return ECONNRESET;
161 case -1:
162 if (errno == EAGAIN)
163 return 0;
164 return errno;
165 default:
166 howmuch -= n;
167 puffs_framebuf_seekset(pb, CUROFF(pb) + n);
168 break;
169 }
170 }
171
172 *done = 1;
173 return 0;
174 }
175 #undef CUROFF
176
177 int
psbuf_cmp(struct puffs_usermount * pu,struct puffs_framebuf * cmp1,struct puffs_framebuf * cmp2,int * notresp)178 psbuf_cmp(struct puffs_usermount *pu,
179 struct puffs_framebuf *cmp1, struct puffs_framebuf *cmp2, int *notresp)
180 {
181
182 return psbuf_get_reqid(cmp1) != psbuf_get_reqid(cmp2);
183 }
184
185 struct puffs_framebuf *
psbuf_makeout()186 psbuf_makeout()
187 {
188 struct puffs_framebuf *pb;
189
190 pb = puffs_framebuf_make();
191 puffs_framebuf_seekset(pb, 4);
192 return pb;
193 }
194
195 void
psbuf_recycleout(struct puffs_framebuf * pb)196 psbuf_recycleout(struct puffs_framebuf *pb)
197 {
198
199 puffs_framebuf_recycle(pb);
200 puffs_framebuf_seekset(pb, 4);
201 }
202
203 void
psbuf_put_1(struct puffs_framebuf * pb,uint8_t val)204 psbuf_put_1(struct puffs_framebuf *pb, uint8_t val)
205 {
206 int rv;
207
208 rv = puffs_framebuf_putdata(pb, &val, 1);
209 CHECK(rv == 0);
210 }
211
212 void
psbuf_put_2(struct puffs_framebuf * pb,uint16_t val)213 psbuf_put_2(struct puffs_framebuf *pb, uint16_t val)
214 {
215 int rv;
216
217 HTOBE16(val);
218 rv = puffs_framebuf_putdata(pb, &val, 2);
219 CHECK(rv == 0);
220 }
221
222 void
psbuf_put_4(struct puffs_framebuf * pb,uint32_t val)223 psbuf_put_4(struct puffs_framebuf *pb, uint32_t val)
224 {
225 int rv;
226
227 HTOBE32(val);
228 rv = puffs_framebuf_putdata(pb, &val, 4);
229 CHECK(rv == 0);
230 }
231
232 void
psbuf_put_8(struct puffs_framebuf * pb,uint64_t val)233 psbuf_put_8(struct puffs_framebuf *pb, uint64_t val)
234 {
235 int rv;
236
237 HTOBE64(val);
238 rv = puffs_framebuf_putdata(pb, &val, 8);
239 CHECK(rv == 0);
240 }
241
242 void
psbuf_put_data(struct puffs_framebuf * pb,const void * data,uint32_t dlen)243 psbuf_put_data(struct puffs_framebuf *pb, const void *data, uint32_t dlen)
244 {
245 int rv;
246
247 psbuf_put_4(pb, dlen);
248 rv = puffs_framebuf_putdata(pb, data, dlen);
249 CHECK(rv == 0);
250 }
251
252 void
psbuf_put_str(struct puffs_framebuf * pb,const char * str)253 psbuf_put_str(struct puffs_framebuf *pb, const char *str)
254 {
255
256 psbuf_put_data(pb, str, strlen(str));
257 }
258
259 void
psbuf_put_vattr(struct puffs_framebuf * pb,const struct vattr * va,const struct psshfs_ctx * pctx)260 psbuf_put_vattr(struct puffs_framebuf *pb, const struct vattr *va,
261 const struct psshfs_ctx *pctx)
262 {
263 uint32_t flags;
264 uint32_t theuid = -1, thegid = -1;
265 flags = 0;
266
267 if (va->va_size != (uint64_t)PUFFS_VNOVAL)
268 flags |= SSH_FILEXFER_ATTR_SIZE;
269 if (va->va_uid != (uid_t)PUFFS_VNOVAL) {
270 theuid = va->va_uid;
271 if (pctx->domangleuid && theuid == pctx->myuid)
272 theuid = pctx->mangleuid;
273 flags |= SSH_FILEXFER_ATTR_UIDGID;
274 }
275 if (va->va_gid != (gid_t)PUFFS_VNOVAL) {
276 thegid = va->va_gid;
277 if (pctx->domanglegid && thegid == pctx->mygid)
278 thegid = pctx->manglegid;
279 flags |= SSH_FILEXFER_ATTR_UIDGID;
280 }
281 if (va->va_mode != (mode_t)PUFFS_VNOVAL)
282 flags |= SSH_FILEXFER_ATTR_PERMISSIONS;
283
284 if (va->va_atime.tv_sec != PUFFS_VNOVAL)
285 flags |= SSH_FILEXFER_ATTR_ACCESSTIME;
286
287 psbuf_put_4(pb, flags);
288 if (flags & SSH_FILEXFER_ATTR_SIZE)
289 psbuf_put_8(pb, va->va_size);
290 if (flags & SSH_FILEXFER_ATTR_UIDGID) {
291 psbuf_put_4(pb, theuid);
292 psbuf_put_4(pb, thegid);
293 }
294 if (flags & SSH_FILEXFER_ATTR_PERMISSIONS)
295 psbuf_put_4(pb, va->va_mode);
296
297 /* XXX: this is totally wrong for protocol v3, see OpenSSH */
298 if (flags & SSH_FILEXFER_ATTR_ACCESSTIME) {
299 psbuf_put_4(pb, va->va_atime.tv_sec);
300 psbuf_put_4(pb, va->va_mtime.tv_sec);
301 }
302 }
303
304 #define ERETURN(rv) return ((rv) == -1 ? errno : 0)
305
306 int
psbuf_get_1(struct puffs_framebuf * pb,uint8_t * val)307 psbuf_get_1(struct puffs_framebuf *pb, uint8_t *val)
308 {
309
310 ERETURN(puffs_framebuf_getdata(pb, val, 1));
311 }
312
313 int
psbuf_get_2(struct puffs_framebuf * pb,uint16_t * val)314 psbuf_get_2(struct puffs_framebuf *pb, uint16_t *val)
315 {
316 int rv;
317
318 rv = puffs_framebuf_getdata(pb, val, 2);
319 BE16TOH(*val);
320
321 ERETURN(rv);
322 }
323
324 int
psbuf_get_4(struct puffs_framebuf * pb,uint32_t * val)325 psbuf_get_4(struct puffs_framebuf *pb, uint32_t *val)
326 {
327 int rv;
328
329 rv = puffs_framebuf_getdata(pb, val, 4);
330 BE32TOH(*val);
331
332 ERETURN(rv);
333 }
334
335 int
psbuf_get_8(struct puffs_framebuf * pb,uint64_t * val)336 psbuf_get_8(struct puffs_framebuf *pb, uint64_t *val)
337 {
338 int rv;
339
340 rv = puffs_framebuf_getdata(pb, val, 8);
341 BE64TOH(*val);
342
343 ERETURN(rv);
344 }
345
346 int
psbuf_get_str(struct puffs_framebuf * pb,char ** strp,uint32_t * strlenp)347 psbuf_get_str(struct puffs_framebuf *pb, char **strp, uint32_t *strlenp)
348 {
349 char *str;
350 uint32_t len;
351
352 FAILRV(psbuf_get_4(pb, &len));
353
354 if (puffs_framebuf_remaining(pb) < len)
355 return EPROTO;
356
357 str = emalloc(len+1);
358 puffs_framebuf_getdata(pb, str, len);
359 str[len] = '\0';
360 *strp = str;
361
362 if (strlenp)
363 *strlenp = len;
364
365 return 0;
366 }
367
368 int
psbuf_get_vattr(struct puffs_framebuf * pb,struct vattr * vap)369 psbuf_get_vattr(struct puffs_framebuf *pb, struct vattr *vap)
370 {
371 uint32_t flags;
372 uint32_t val;
373
374 puffs_vattr_null(vap);
375
376 FAILRV(psbuf_get_4(pb, &flags));
377
378 if (flags & SSH_FILEXFER_ATTR_SIZE) {
379 FAILRV(psbuf_get_8(pb, &vap->va_size));
380 vap->va_bytes = vap->va_size;
381 }
382 if (flags & SSH_FILEXFER_ATTR_UIDGID) {
383 FAILRV(psbuf_get_4(pb, &vap->va_uid));
384 FAILRV(psbuf_get_4(pb, &vap->va_gid));
385 }
386 if (flags & SSH_FILEXFER_ATTR_PERMISSIONS) {
387 FAILRV(psbuf_get_4(pb, &vap->va_mode));
388 vap->va_type = puffs_mode2vt(vap->va_mode);
389 }
390 if (flags & SSH_FILEXFER_ATTR_ACCESSTIME) {
391 /*
392 * XXX: this is utterly wrong if we want to speak
393 * protocol version 3, but it seems like the
394 * "internet standard" for doing this
395 */
396 FAILRV(psbuf_get_4(pb, &val));
397 vap->va_atime.tv_sec = val;
398 FAILRV(psbuf_get_4(pb, &val));
399 vap->va_mtime.tv_sec = val;
400 /* make ctime the same as mtime */
401 vap->va_ctime.tv_sec = val;
402
403 vap->va_atime.tv_nsec = 0;
404 vap->va_ctime.tv_nsec = 0;
405 vap->va_mtime.tv_nsec = 0;
406 }
407
408 return 0;
409 }
410
411 /*
412 * Buffer content helpers. Caller frees all data.
413 */
414
415 /*
416 * error mapping.. most are not expected for a file system, but
417 * should help with diagnosing a possible error
418 */
419 static int emap[] = {
420 0, /* OK */
421 0, /* EOF */
422 ENOENT, /* NO_SUCH_FILE */
423 EPERM, /* PERMISSION_DENIED */
424 EIO, /* FAILURE */
425 EBADMSG, /* BAD_MESSAGE */
426 ENOTCONN, /* NO_CONNECTION */
427 ECONNRESET, /* CONNECTION_LOST */
428 EOPNOTSUPP, /* OP_UNSUPPORTED */
429 EINVAL, /* INVALID_HANDLE */
430 ENXIO, /* NO_SUCH_PATH */
431 EEXIST, /* FILE_ALREADY_EXISTS */
432 ENODEV /* WRITE_PROTECT */
433 };
434 #define NERRORS ((int)(sizeof(emap) / sizeof(emap[0])))
435
436 static int
sftperr_to_errno(int error)437 sftperr_to_errno(int error)
438 {
439
440 if (!error)
441 return 0;
442
443 if (error >= NERRORS || error < 0)
444 return EPROTO;
445
446 return emap[error];
447 }
448
449 #define INVALRESPONSE EPROTO
450
451 static int
expectcode(struct puffs_framebuf * pb,int value)452 expectcode(struct puffs_framebuf *pb, int value)
453 {
454 uint32_t error;
455 uint8_t type;
456
457 type = psbuf_get_type(pb);
458 if (type == value)
459 return 0;
460
461 if (type != SSH_FXP_STATUS)
462 return INVALRESPONSE;
463
464 FAILRV(psbuf_get_4(pb, &error));
465
466 return sftperr_to_errno(error);
467 }
468
469 #define CHECKCODE(pb,val) \
470 do { \
471 int rv; \
472 rv = expectcode(pb, val); \
473 if (rv) \
474 return rv; \
475 } while (/*CONSTCOND*/0)
476
477 int
psbuf_expect_status(struct puffs_framebuf * pb)478 psbuf_expect_status(struct puffs_framebuf *pb)
479 {
480 uint32_t error;
481
482 if (psbuf_get_type(pb) != SSH_FXP_STATUS)
483 return INVALRESPONSE;
484
485 FAILRV(psbuf_get_4(pb, &error));
486
487 return sftperr_to_errno(error);
488 }
489
490 int
psbuf_expect_handle(struct puffs_framebuf * pb,char ** hand,uint32_t * handlen)491 psbuf_expect_handle(struct puffs_framebuf *pb, char **hand, uint32_t *handlen)
492 {
493
494 CHECKCODE(pb, SSH_FXP_HANDLE);
495 FAILRV(psbuf_get_str(pb, hand, handlen));
496
497 return 0;
498 }
499
500 /* no memory allocation, direct copy */
501 int
psbuf_do_data(struct puffs_framebuf * pb,uint8_t * data,uint32_t * dlen)502 psbuf_do_data(struct puffs_framebuf *pb, uint8_t *data, uint32_t *dlen)
503 {
504 void *win;
505 size_t bufoff, winlen;
506 uint32_t len, dataoff;
507
508 if (psbuf_get_type(pb) != SSH_FXP_DATA) {
509 uint32_t val;
510
511 if (psbuf_get_type(pb) != SSH_FXP_STATUS)
512 return INVALRESPONSE;
513
514 if (psbuf_get_4(pb, &val) != 0)
515 return INVALRESPONSE;
516
517 if (val != SSH_FX_EOF)
518 return sftperr_to_errno(val);
519
520 *dlen = 0;
521 return 0;
522 }
523 if (psbuf_get_4(pb, &len) != 0)
524 return INVALRESPONSE;
525
526 if (*dlen < len)
527 return EINVAL;
528
529 *dlen = 0;
530
531 dataoff = 0;
532 while (dataoff < len) {
533 winlen = len-dataoff;
534 bufoff = puffs_framebuf_telloff(pb);
535 if (puffs_framebuf_getwindow(pb, bufoff,
536 &win, &winlen) == -1)
537 return EINVAL;
538 if (winlen == 0)
539 break;
540
541 memcpy(data + dataoff, win, winlen);
542 dataoff += winlen;
543 }
544
545 *dlen = dataoff;
546
547 return 0;
548 }
549
550 int
psbuf_expect_name(struct puffs_framebuf * pb,uint32_t * count)551 psbuf_expect_name(struct puffs_framebuf *pb, uint32_t *count)
552 {
553
554 CHECKCODE(pb, SSH_FXP_NAME);
555 FAILRV(psbuf_get_4(pb, count));
556
557 return 0;
558 }
559
560 int
psbuf_expect_attrs(struct puffs_framebuf * pb,struct vattr * vap)561 psbuf_expect_attrs(struct puffs_framebuf *pb, struct vattr *vap)
562 {
563
564 CHECKCODE(pb, SSH_FXP_ATTRS);
565 FAILRV(psbuf_get_vattr(pb, vap));
566
567 return 0;
568 }
569
570 /*
571 * More helpers: larger-scale put functions
572 */
573
574 void
psbuf_req_data(struct puffs_framebuf * pb,int type,uint32_t reqid,const void * data,uint32_t dlen)575 psbuf_req_data(struct puffs_framebuf *pb, int type, uint32_t reqid,
576 const void *data, uint32_t dlen)
577 {
578
579 psbuf_put_1(pb, type);
580 psbuf_put_4(pb, reqid);
581 psbuf_put_data(pb, data, dlen);
582 }
583
584 void
psbuf_req_str(struct puffs_framebuf * pb,int type,uint32_t reqid,const char * str)585 psbuf_req_str(struct puffs_framebuf *pb, int type, uint32_t reqid,
586 const char *str)
587 {
588
589 psbuf_req_data(pb, type, reqid, str, strlen(str));
590 }
591