xref: /illumos-gate/usr/src/lib/lib9p/common/pack.c (revision 66597161e2ba69a84fa138bce7ac02a1e6b9746c)
1 /*
2  * Copyright 2016 Jakub Klama <jceel@FreeBSD.org>
3  * All rights reserved
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted providing that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
18  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
23  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24  * POSSIBILITY OF SUCH DAMAGE.
25  *
26  */
27 
28 /*
29  * Based on libixp code: ©2007-2010 Kris Maglione <maglione.k at Gmail>
30  */
31 
32 #include <stdlib.h>
33 #include <string.h>
34 #include <assert.h>
35 #include <sys/types.h>
36 #include <sys/param.h>
37 #ifdef __APPLE__
38 # include "apple_endian.h"
39 #elif __illumos__
40 # include "illumos_endian.h"
41 # include <sys/sysmacros.h>
42 #else
43 # include <sys/endian.h>
44 #endif
45 #include <sys/uio.h>
46 #include "lib9p.h"
47 #include "lib9p_impl.h"
48 #include "log.h"
49 
50 #define N(ary)          (sizeof(ary) / sizeof(*ary))
51 #define STRING_SIZE(s)  (L9P_WORD + (s != NULL ? (uint16_t)strlen(s) : 0))
52 #define QID_SIZE        (L9P_BYTE + L9P_DWORD + L9P_QWORD)
53 
54 static ssize_t l9p_iov_io(struct l9p_message *, void *, size_t);
55 static inline ssize_t l9p_pu8(struct l9p_message *, uint8_t *);
56 static inline ssize_t l9p_pu16(struct l9p_message *, uint16_t *);
57 static inline ssize_t l9p_pu32(struct l9p_message *, uint32_t *);
58 static inline ssize_t l9p_pu64(struct l9p_message *, uint64_t *);
59 static ssize_t l9p_pustring(struct l9p_message *, char **s);
60 static ssize_t l9p_pustrings(struct l9p_message *, uint16_t *, char **, size_t);
61 static ssize_t l9p_puqid(struct l9p_message *, struct l9p_qid *);
62 static ssize_t l9p_puqids(struct l9p_message *, uint16_t *, struct l9p_qid *q);
63 
64 /*
65  * Transfer data from incoming request, or to outgoing response,
66  * using msg to track position and direction within request/response.
67  *
68  * Returns the number of bytes actually transferred (which is always
69  * just len itself, converted to signed), or -1 if we ran out of space.
70  *
71  * Note that if we return -1, subsequent l9p_iov_io() calls with
72  * the same (and not-reset) msg and len > 0 will also return -1.
73  * This means most users can just check the *last* call for failure.
74  */
75 static ssize_t
76 l9p_iov_io(struct l9p_message *msg, void *buffer, size_t len)
77 {
78 	size_t done = 0;
79 	size_t left = len;
80 
81 	assert(msg != NULL);
82 
83 	if (len == 0)
84 		return (0);
85 
86 	if (msg->lm_cursor_iov >= msg->lm_niov)
87 		return (-1);
88 
89 	assert(buffer != NULL);
90 
91 	while (left > 0) {
92 		size_t idx = msg->lm_cursor_iov;
93 		size_t space = msg->lm_iov[idx].iov_len - msg->lm_cursor_offset;
94 		size_t towrite = MIN(space, left);
95 
96 		if (msg->lm_mode == L9P_PACK) {
97 			memcpy((char *)msg->lm_iov[idx].iov_base +
98 			    msg->lm_cursor_offset, (char *)buffer + done,
99 			    towrite);
100 		}
101 
102 		if (msg->lm_mode == L9P_UNPACK) {
103 			memcpy((char *)buffer + done,
104 			    (char *)msg->lm_iov[idx].iov_base +
105 			    msg->lm_cursor_offset, towrite);
106 		}
107 
108 		msg->lm_cursor_offset += towrite;
109 
110 		done += towrite;
111 		left -= towrite;
112 
113 		if (space - towrite == 0) {
114 			/* Advance to next iov */
115 			msg->lm_cursor_iov++;
116 			msg->lm_cursor_offset = 0;
117 
118 			if (msg->lm_cursor_iov >= msg->lm_niov && left > 0)
119 				return (-1);
120 		}
121 	}
122 
123 	msg->lm_size += done;
124 	return ((ssize_t)done);
125 }
126 
127 /*
128  * Pack or unpack a byte (8 bits).
129  *
130  * Returns 1 (success, 1 byte) or -1 (error).
131  */
132 static inline ssize_t
133 l9p_pu8(struct l9p_message *msg, uint8_t *val)
134 {
135 
136 	return (l9p_iov_io(msg, val, sizeof (uint8_t)));
137 }
138 
139 /*
140  * Pack or unpack 16-bit value.
141  *
142  * Returns 2 or -1.
143  */
144 static inline ssize_t
145 l9p_pu16(struct l9p_message *msg, uint16_t *val)
146 {
147 #if _BYTE_ORDER != _LITTLE_ENDIAN
148 	/*
149 	 * The ifdefs are annoying, but there is no need
150 	 * for all of this foolery on little-endian hosts,
151 	 * and I don't expect the compiler to optimize it
152 	 * all away.
153 	 */
154 	uint16_t copy;
155 	ssize_t ret;
156 
157 	if (msg->lm_mode == L9P_PACK) {
158 		copy = htole16(*val);
159 		return (l9p_iov_io(msg, &copy, sizeof (uint16_t)));
160 	}
161 	ret = l9p_iov_io(msg, val, sizeof (uint16_t));
162 	*val = le16toh(*val);
163 	return (ret);
164 #else
165 	return (l9p_iov_io(msg, val, sizeof (uint16_t)));
166 #endif
167 }
168 
169 /*
170  * Pack or unpack 32-bit value.
171  *
172  * Returns 4 or -1.
173  */
174 static inline ssize_t
175 l9p_pu32(struct l9p_message *msg, uint32_t *val)
176 {
177 #if _BYTE_ORDER != _LITTLE_ENDIAN
178 	uint32_t copy;
179 	ssize_t ret;
180 
181 	if (msg->lm_mode == L9P_PACK) {
182 		copy = htole32(*val);
183 		return (l9p_iov_io(msg, &copy, sizeof (uint32_t)));
184 	}
185 	ret = l9p_iov_io(msg, val, sizeof (uint32_t));
186 	*val = le32toh(*val);
187 	return (ret);
188 #else
189 	return (l9p_iov_io(msg, val, sizeof (uint32_t)));
190 #endif
191 }
192 
193 /*
194  * Pack or unpack 64-bit value.
195  *
196  * Returns 8 or -1.
197  */
198 static inline ssize_t
199 l9p_pu64(struct l9p_message *msg, uint64_t *val)
200 {
201 #if _BYTE_ORDER != _LITTLE_ENDIAN
202 	uint64_t copy;
203 	ssize_t ret;
204 
205 	if (msg->lm_mode == L9P_PACK) {
206 		copy = htole64(*val);
207 		return (l9p_iov_io(msg, &copy, sizeof (uint64_t)));
208 	}
209 	ret = l9p_iov_io(msg, val, sizeof (uint32_t));
210 	*val = le64toh(*val);
211 	return (ret);
212 #else
213 	return (l9p_iov_io(msg, val, sizeof (uint64_t)));
214 #endif
215 }
216 
217 /*
218  * Pack or unpack a string, encoded as 2-byte length followed by
219  * string bytes.  The returned length is 2 greater than the
220  * length of the string itself.
221  *
222  * When unpacking, this allocates a new string (NUL-terminated).
223  *
224  * Return -1 on error (not space, or failed to allocate string,
225  * or illegal string).
226  *
227  * Note that pustring (and hence pustrings) can return an error
228  * even when l9p_iov_io succeeds.
229  */
230 static ssize_t
231 l9p_pustring(struct l9p_message *msg, char **s)
232 {
233 	uint16_t len;
234 
235 	if (msg->lm_mode == L9P_PACK)
236 		len = *s != NULL ? (uint16_t)strlen(*s) : 0;
237 
238 	if (l9p_pu16(msg, &len) < 0)
239 		return (-1);
240 
241 	if (msg->lm_mode == L9P_UNPACK) {
242 		*s = l9p_calloc(1, len + 1);
243 		if (*s == NULL)
244 			return (-1);
245 	}
246 
247 	if (l9p_iov_io(msg, *s, len) < 0)
248 		return (-1);
249 
250 	if (msg->lm_mode == L9P_UNPACK) {
251 		/*
252 		 * An embedded NUL byte in a string is illegal.
253 		 * We don't necessarily have to check (we'll just
254 		 * treat it as a shorter string), but checking
255 		 * seems like a good idea.
256 		 */
257 		if (memchr(*s, '\0', len) != NULL)
258 			return (-1);
259 	}
260 
261 	return ((ssize_t)len + 2);
262 }
263 
264 /*
265  * Pack or unpack a number (*num) of strings (but at most max of
266  * them).
267  *
268  * Returns the number of bytes transferred, including the packed
269  * number of strings.  If packing and the packed number of strings
270  * was reduced, the original *num value is unchanged; only the
271  * wire-format number is reduced.  If unpacking and the input
272  * number of strings exceeds the max, the incoming *num is reduced
273  * to lim, if needed.  (NOTE ASYMMETRY HERE!)
274  *
275  * Returns -1 on error.
276  */
277 static ssize_t
278 l9p_pustrings(struct l9p_message *msg, uint16_t *num, char **strings,
279     size_t max)
280 {
281 	size_t i, lim;
282 	ssize_t r, ret;
283 	uint16_t adjusted;
284 
285 	if (msg->lm_mode == L9P_PACK) {
286 		lim = *num;
287 		if (lim > max)
288 			lim = max;
289 		adjusted = (uint16_t)lim;
290 		r = l9p_pu16(msg, &adjusted);
291 	} else {
292 		r = l9p_pu16(msg, num);
293 		lim = *num;
294 		if (lim > max)
295 			*num = (uint16_t)(lim = max);
296 	}
297 	if (r < 0)
298 		return (-1);
299 
300 	for (i = 0; i < lim; i++) {
301 		ret = l9p_pustring(msg, &strings[i]);
302 		if (ret < 1)
303 			return (-1);
304 
305 		r += ret;
306 	}
307 
308 	return (r);
309 }
310 
311 /*
312  * Pack or unpack a qid.
313  *
314  * Returns 13 (success) or -1 (error).
315  */
316 static ssize_t
317 l9p_puqid(struct l9p_message *msg, struct l9p_qid *qid)
318 {
319 	ssize_t r;
320 	uint8_t type;
321 
322 	if (msg->lm_mode == L9P_PACK) {
323 		type = qid->type;
324 		r = l9p_pu8(msg, &type);
325 	} else {
326 		r = l9p_pu8(msg, &type);
327 		qid->type = type;
328 	}
329 	if (r > 0)
330 		r = l9p_pu32(msg, &qid->version);
331 	if (r > 0)
332 		r = l9p_pu64(msg, &qid->path);
333 
334 	return (r > 0 ? QID_SIZE : r);
335 }
336 
337 /*
338  * Pack or unpack *num qids.
339  *
340  * Returns 2 + 13 * *num (after possibly setting *num), or -1 on error.
341  */
342 static ssize_t
343 l9p_puqids(struct l9p_message *msg, uint16_t *num, struct l9p_qid *qids)
344 {
345 	size_t i, lim;
346 	ssize_t ret, r;
347 
348 	r = l9p_pu16(msg, num);
349 	if (r > 0) {
350 		for (i = 0, lim = *num; i < lim; i++) {
351 			ret = l9p_puqid(msg, &qids[i]);
352 			if (ret < 0)
353 				return (-1);
354 			r += ret;
355 		}
356 	}
357 	return (r);
358 }
359 
360 /*
361  * Pack or unpack a l9p_stat.
362  *
363  * These have variable size, and the size further depends on
364  * the protocol version.
365  *
366  * Returns the number of bytes packed/unpacked, or -1 on error.
367  */
368 ssize_t
369 l9p_pustat(struct l9p_message *msg, struct l9p_stat *stat,
370     enum l9p_version version)
371 {
372 	ssize_t r = 0;
373 	uint16_t size;
374 
375 	/* The on-wire size field excludes the size of the size field. */
376 	if (msg->lm_mode == L9P_PACK)
377 		size = l9p_sizeof_stat(stat, version) - 2;
378 
379 	r += l9p_pu16(msg, &size);
380 	r += l9p_pu16(msg, &stat->type);
381 	r += l9p_pu32(msg, &stat->dev);
382 	r += l9p_puqid(msg, &stat->qid);
383 	r += l9p_pu32(msg, &stat->mode);
384 	r += l9p_pu32(msg, &stat->atime);
385 	r += l9p_pu32(msg, &stat->mtime);
386 	r += l9p_pu64(msg, &stat->length);
387 	r += l9p_pustring(msg, &stat->name);
388 	r += l9p_pustring(msg, &stat->uid);
389 	r += l9p_pustring(msg, &stat->gid);
390 	r += l9p_pustring(msg, &stat->muid);
391 
392 	if (version >= L9P_2000U) {
393 		r += l9p_pustring(msg, &stat->extension);
394 		r += l9p_pu32(msg, &stat->n_uid);
395 		r += l9p_pu32(msg, &stat->n_gid);
396 		r += l9p_pu32(msg, &stat->n_muid);
397 	}
398 
399 	if (r < size + 2)
400 		return (-1);
401 
402 	return (r);
403 }
404 
405 /*
406  * Pack or unpack a variable-length dirent.
407  *
408  * If unpacking, the name field is malloc()ed and the caller must
409  * free it.
410  *
411  * Returns the wire-format length, or -1 if we ran out of room.
412  */
413 ssize_t
414 l9p_pudirent(struct l9p_message *msg, struct l9p_dirent *de)
415 {
416 	ssize_t r, s;
417 
418 	r = l9p_puqid(msg, &de->qid);
419 	r += l9p_pu64(msg, &de->offset);
420 	r += l9p_pu8(msg, &de->type);
421 	s = l9p_pustring(msg, &de->name);
422 	if (r < QID_SIZE + 8 + 1 || s < 0)
423 		return (-1);
424 	return (r + s);
425 }
426 
427 /*
428  * Pack or unpack a request or response (fcall).
429  *
430  * Returns 0 on success, -1 on error.  (It's up to the caller
431  * to call l9p_freefcall on our failure.)
432  */
433 int
434 l9p_pufcall(struct l9p_message *msg, union l9p_fcall *fcall,
435     enum l9p_version version)
436 {
437 	uint32_t length = 0;
438 	ssize_t r;
439 
440 	/*
441 	 * Get overall length, type, and tag, which should appear
442 	 * in all messages.  If not even that works, abort immediately.
443 	 */
444 	l9p_pu32(msg, &length);
445 	l9p_pu8(msg, &fcall->hdr.type);
446 	r = l9p_pu16(msg, &fcall->hdr.tag);
447 	if (r < 0)
448 		return (-1);
449 
450 	/*
451 	 * Decode remainder of message.	 When unpacking, this may
452 	 * allocate memory, even if we fail during the decode.
453 	 * Note that the initial fcall is zeroed out, though, so
454 	 * we can just freefcall() to release whatever might have
455 	 * gotten allocated, if the unpack fails due to a short
456 	 * packet.
457 	 */
458 	switch (fcall->hdr.type) {
459 	case L9P_TVERSION:
460 	case L9P_RVERSION:
461 		l9p_pu32(msg, &fcall->version.msize);
462 		r = l9p_pustring(msg, &fcall->version.version);
463 		break;
464 
465 	case L9P_TAUTH:
466 		l9p_pu32(msg, &fcall->tauth.afid);
467 		r = l9p_pustring(msg, &fcall->tauth.uname);
468 		if (r < 0)
469 			break;
470 		r = l9p_pustring(msg, &fcall->tauth.aname);
471 		if (r < 0)
472 			break;
473 		if (version >= L9P_2000U)
474 			r = l9p_pu32(msg, &fcall->tauth.n_uname);
475 		break;
476 
477 	case L9P_RAUTH:
478 		r = l9p_puqid(msg, &fcall->rauth.aqid);
479 		break;
480 
481 	case L9P_TATTACH:
482 		l9p_pu32(msg, &fcall->hdr.fid);
483 		l9p_pu32(msg, &fcall->tattach.afid);
484 		r = l9p_pustring(msg, &fcall->tattach.uname);
485 		if (r < 0)
486 			break;
487 		r = l9p_pustring(msg, &fcall->tattach.aname);
488 		if (r < 0)
489 			break;
490 		if (version >= L9P_2000U)
491 			r = l9p_pu32(msg, &fcall->tattach.n_uname);
492 		break;
493 
494 	case L9P_RATTACH:
495 		r = l9p_puqid(msg, &fcall->rattach.qid);
496 		break;
497 
498 	case L9P_RERROR:
499 		r = l9p_pustring(msg, &fcall->error.ename);
500 		if (r < 0)
501 			break;
502 		if (version >= L9P_2000U)
503 			r = l9p_pu32(msg, &fcall->error.errnum);
504 		break;
505 
506 	case L9P_RLERROR:
507 		r = l9p_pu32(msg, &fcall->error.errnum);
508 		break;
509 
510 	case L9P_TFLUSH:
511 		r = l9p_pu16(msg, &fcall->tflush.oldtag);
512 		break;
513 
514 	case L9P_RFLUSH:
515 		break;
516 
517 	case L9P_TWALK:
518 		l9p_pu32(msg, &fcall->hdr.fid);
519 		l9p_pu32(msg, &fcall->twalk.newfid);
520 		r = l9p_pustrings(msg, &fcall->twalk.nwname,
521 		    fcall->twalk.wname, N(fcall->twalk.wname));
522 		break;
523 
524 	case L9P_RWALK:
525 		r = l9p_puqids(msg, &fcall->rwalk.nwqid, fcall->rwalk.wqid);
526 		break;
527 
528 	case L9P_TOPEN:
529 		l9p_pu32(msg, &fcall->hdr.fid);
530 		r = l9p_pu8(msg, &fcall->topen.mode);
531 		break;
532 
533 	case L9P_ROPEN:
534 		l9p_puqid(msg, &fcall->ropen.qid);
535 		r = l9p_pu32(msg, &fcall->ropen.iounit);
536 		break;
537 
538 	case L9P_TCREATE:
539 		l9p_pu32(msg, &fcall->hdr.fid);
540 		r = l9p_pustring(msg, &fcall->tcreate.name);
541 		if (r < 0)
542 			break;
543 		l9p_pu32(msg, &fcall->tcreate.perm);
544 		r = l9p_pu8(msg, &fcall->tcreate.mode);
545 		if (version >= L9P_2000U)
546 			r = l9p_pustring(msg, &fcall->tcreate.extension);
547 		break;
548 
549 	case L9P_RCREATE:
550 		l9p_puqid(msg, &fcall->rcreate.qid);
551 		r = l9p_pu32(msg, &fcall->rcreate.iounit);
552 		break;
553 
554 	case L9P_TREAD:
555 	case L9P_TREADDIR:
556 		l9p_pu32(msg, &fcall->hdr.fid);
557 		l9p_pu64(msg, &fcall->io.offset);
558 		r = l9p_pu32(msg, &fcall->io.count);
559 		break;
560 
561 	case L9P_RREAD:
562 	case L9P_RREADDIR:
563 		r = l9p_pu32(msg, &fcall->io.count);
564 		break;
565 
566 	case L9P_TWRITE:
567 		l9p_pu32(msg, &fcall->hdr.fid);
568 		l9p_pu64(msg, &fcall->io.offset);
569 		r = l9p_pu32(msg, &fcall->io.count);
570 		break;
571 
572 	case L9P_RWRITE:
573 		r = l9p_pu32(msg, &fcall->io.count);
574 		break;
575 
576 	case L9P_TCLUNK:
577 	case L9P_TSTAT:
578 	case L9P_TREMOVE:
579 	case L9P_TSTATFS:
580 		r = l9p_pu32(msg, &fcall->hdr.fid);
581 		break;
582 
583 	case L9P_RCLUNK:
584 	case L9P_RREMOVE:
585 		break;
586 
587 	case L9P_RSTAT:
588 	{
589 		uint16_t size = l9p_sizeof_stat(&fcall->rstat.stat,
590 		    version);
591 		l9p_pu16(msg, &size);
592 		r = l9p_pustat(msg, &fcall->rstat.stat, version);
593 	}
594 		break;
595 
596 	case L9P_TWSTAT:
597 	{
598 		uint16_t size;
599 		l9p_pu32(msg, &fcall->hdr.fid);
600 		l9p_pu16(msg, &size);
601 		r = l9p_pustat(msg, &fcall->twstat.stat, version);
602 	}
603 		break;
604 
605 	case L9P_RWSTAT:
606 		break;
607 
608 	case L9P_RSTATFS:
609 		l9p_pu32(msg, &fcall->rstatfs.statfs.type);
610 		l9p_pu32(msg, &fcall->rstatfs.statfs.bsize);
611 		l9p_pu64(msg, &fcall->rstatfs.statfs.blocks);
612 		l9p_pu64(msg, &fcall->rstatfs.statfs.bfree);
613 		l9p_pu64(msg, &fcall->rstatfs.statfs.bavail);
614 		l9p_pu64(msg, &fcall->rstatfs.statfs.files);
615 		l9p_pu64(msg, &fcall->rstatfs.statfs.ffree);
616 		l9p_pu64(msg, &fcall->rstatfs.statfs.fsid);
617 		r = l9p_pu32(msg, &fcall->rstatfs.statfs.namelen);
618 		break;
619 
620 	case L9P_TLOPEN:
621 		l9p_pu32(msg, &fcall->hdr.fid);
622 		r = l9p_pu32(msg, &fcall->tlopen.flags);
623 		break;
624 
625 	case L9P_RLOPEN:
626 		l9p_puqid(msg, &fcall->rlopen.qid);
627 		r = l9p_pu32(msg, &fcall->rlopen.iounit);
628 		break;
629 
630 	case L9P_TLCREATE:
631 		l9p_pu32(msg, &fcall->hdr.fid);
632 		r = l9p_pustring(msg, &fcall->tlcreate.name);
633 		if (r < 0)
634 			break;
635 		l9p_pu32(msg, &fcall->tlcreate.flags);
636 		l9p_pu32(msg, &fcall->tlcreate.mode);
637 		r = l9p_pu32(msg, &fcall->tlcreate.gid);
638 		break;
639 
640 	case L9P_RLCREATE:
641 		l9p_puqid(msg, &fcall->rlcreate.qid);
642 		r = l9p_pu32(msg, &fcall->rlcreate.iounit);
643 		break;
644 
645 	case L9P_TSYMLINK:
646 		l9p_pu32(msg, &fcall->hdr.fid);
647 		r = l9p_pustring(msg, &fcall->tsymlink.name);
648 		if (r < 0)
649 			break;
650 		r = l9p_pustring(msg, &fcall->tsymlink.symtgt);
651 		if (r < 0)
652 			break;
653 		r = l9p_pu32(msg, &fcall->tlcreate.gid);
654 		break;
655 
656 	case L9P_RSYMLINK:
657 		r = l9p_puqid(msg, &fcall->rsymlink.qid);
658 		break;
659 
660 	case L9P_TMKNOD:
661 		l9p_pu32(msg, &fcall->hdr.fid);
662 		r = l9p_pustring(msg, &fcall->tmknod.name);
663 		if (r < 0)
664 			break;
665 		l9p_pu32(msg, &fcall->tmknod.mode);
666 		l9p_pu32(msg, &fcall->tmknod.major);
667 		l9p_pu32(msg, &fcall->tmknod.minor);
668 		r = l9p_pu32(msg, &fcall->tmknod.gid);
669 		break;
670 
671 	case L9P_RMKNOD:
672 		r = l9p_puqid(msg, &fcall->rmknod.qid);
673 		break;
674 
675 	case L9P_TRENAME:
676 		l9p_pu32(msg, &fcall->hdr.fid);
677 		l9p_pu32(msg, &fcall->trename.dfid);
678 		r = l9p_pustring(msg, &fcall->trename.name);
679 		break;
680 
681 	case L9P_RRENAME:
682 		break;
683 
684 	case L9P_TREADLINK:
685 		r = l9p_pu32(msg, &fcall->hdr.fid);
686 		break;
687 
688 	case L9P_RREADLINK:
689 		r = l9p_pustring(msg, &fcall->rreadlink.target);
690 		break;
691 
692 	case L9P_TGETATTR:
693 		l9p_pu32(msg, &fcall->hdr.fid);
694 		r = l9p_pu64(msg, &fcall->tgetattr.request_mask);
695 		break;
696 
697 	case L9P_RGETATTR:
698 		l9p_pu64(msg, &fcall->rgetattr.valid);
699 		l9p_puqid(msg, &fcall->rgetattr.qid);
700 		l9p_pu32(msg, &fcall->rgetattr.mode);
701 		l9p_pu32(msg, &fcall->rgetattr.uid);
702 		l9p_pu32(msg, &fcall->rgetattr.gid);
703 		l9p_pu64(msg, &fcall->rgetattr.nlink);
704 		l9p_pu64(msg, &fcall->rgetattr.rdev);
705 		l9p_pu64(msg, &fcall->rgetattr.size);
706 		l9p_pu64(msg, &fcall->rgetattr.blksize);
707 		l9p_pu64(msg, &fcall->rgetattr.blocks);
708 		l9p_pu64(msg, &fcall->rgetattr.atime_sec);
709 		l9p_pu64(msg, &fcall->rgetattr.atime_nsec);
710 		l9p_pu64(msg, &fcall->rgetattr.mtime_sec);
711 		l9p_pu64(msg, &fcall->rgetattr.mtime_nsec);
712 		l9p_pu64(msg, &fcall->rgetattr.ctime_sec);
713 		l9p_pu64(msg, &fcall->rgetattr.ctime_nsec);
714 		l9p_pu64(msg, &fcall->rgetattr.btime_sec);
715 		l9p_pu64(msg, &fcall->rgetattr.btime_nsec);
716 		l9p_pu64(msg, &fcall->rgetattr.gen);
717 		r = l9p_pu64(msg, &fcall->rgetattr.data_version);
718 		break;
719 
720 	case L9P_TSETATTR:
721 		l9p_pu32(msg, &fcall->hdr.fid);
722 		l9p_pu32(msg, &fcall->tsetattr.valid);
723 		l9p_pu32(msg, &fcall->tsetattr.mode);
724 		l9p_pu32(msg, &fcall->tsetattr.uid);
725 		l9p_pu32(msg, &fcall->tsetattr.gid);
726 		l9p_pu64(msg, &fcall->tsetattr.size);
727 		l9p_pu64(msg, &fcall->tsetattr.atime_sec);
728 		l9p_pu64(msg, &fcall->tsetattr.atime_nsec);
729 		l9p_pu64(msg, &fcall->tsetattr.mtime_sec);
730 		r = l9p_pu64(msg, &fcall->tsetattr.mtime_nsec);
731 		break;
732 
733 	case L9P_RSETATTR:
734 		break;
735 
736 	case L9P_TXATTRWALK:
737 		l9p_pu32(msg, &fcall->hdr.fid);
738 		l9p_pu32(msg, &fcall->txattrwalk.newfid);
739 		r = l9p_pustring(msg, &fcall->txattrwalk.name);
740 		break;
741 
742 	case L9P_RXATTRWALK:
743 		r = l9p_pu64(msg, &fcall->rxattrwalk.size);
744 		break;
745 
746 	case L9P_TXATTRCREATE:
747 		l9p_pu32(msg, &fcall->hdr.fid);
748 		r = l9p_pustring(msg, &fcall->txattrcreate.name);
749 		if (r < 0)
750 			break;
751 		l9p_pu64(msg, &fcall->txattrcreate.attr_size);
752 		r = l9p_pu32(msg, &fcall->txattrcreate.flags);
753 		break;
754 
755 	case L9P_RXATTRCREATE:
756 		break;
757 
758 	case L9P_TFSYNC:
759 		r = l9p_pu32(msg, &fcall->hdr.fid);
760 		break;
761 
762 	case L9P_RFSYNC:
763 		break;
764 
765 	case L9P_TLOCK:
766 		l9p_pu32(msg, &fcall->hdr.fid);
767 		l9p_pu8(msg, &fcall->tlock.type);
768 		l9p_pu32(msg, &fcall->tlock.flags);
769 		l9p_pu64(msg, &fcall->tlock.start);
770 		l9p_pu64(msg, &fcall->tlock.length);
771 		l9p_pu32(msg, &fcall->tlock.proc_id);
772 		r = l9p_pustring(msg, &fcall->tlock.client_id);
773 		break;
774 
775 	case L9P_RLOCK:
776 		r = l9p_pu8(msg, &fcall->rlock.status);
777 		break;
778 
779 	case L9P_TGETLOCK:
780 		l9p_pu32(msg, &fcall->hdr.fid);
781 		/* FALLTHROUGH */
782 
783 	case L9P_RGETLOCK:
784 		l9p_pu8(msg, &fcall->getlock.type);
785 		l9p_pu64(msg, &fcall->getlock.start);
786 		l9p_pu64(msg, &fcall->getlock.length);
787 		l9p_pu32(msg, &fcall->getlock.proc_id);
788 		r = l9p_pustring(msg, &fcall->getlock.client_id);
789 		break;
790 
791 	case L9P_TLINK:
792 		l9p_pu32(msg, &fcall->tlink.dfid);
793 		l9p_pu32(msg, &fcall->hdr.fid);
794 		r = l9p_pustring(msg, &fcall->tlink.name);
795 		break;
796 
797 	case L9P_RLINK:
798 		break;
799 
800 	case L9P_TMKDIR:
801 		l9p_pu32(msg, &fcall->hdr.fid);
802 		r = l9p_pustring(msg, &fcall->tmkdir.name);
803 		if (r < 0)
804 			break;
805 		l9p_pu32(msg, &fcall->tmkdir.mode);
806 		r = l9p_pu32(msg, &fcall->tmkdir.gid);
807 		break;
808 
809 	case L9P_RMKDIR:
810 		r = l9p_puqid(msg, &fcall->rmkdir.qid);
811 		break;
812 
813 	case L9P_TRENAMEAT:
814 		l9p_pu32(msg, &fcall->hdr.fid);
815 		r = l9p_pustring(msg, &fcall->trenameat.oldname);
816 		if (r < 0)
817 			break;
818 		l9p_pu32(msg, &fcall->trenameat.newdirfid);
819 		r = l9p_pustring(msg, &fcall->trenameat.newname);
820 		break;
821 
822 	case L9P_RRENAMEAT:
823 		break;
824 
825 	case L9P_TUNLINKAT:
826 		l9p_pu32(msg, &fcall->hdr.fid);
827 		r = l9p_pustring(msg, &fcall->tunlinkat.name);
828 		if (r < 0)
829 			break;
830 		r = l9p_pu32(msg, &fcall->tunlinkat.flags);
831 		break;
832 
833 	case L9P_RUNLINKAT:
834 		break;
835 
836 	default:
837 		L9P_LOG(L9P_ERROR, "%s(): missing case for type %d",
838 		    __func__, fcall->hdr.type);
839 		break;
840 	}
841 
842 	/* Check for over- or under-run, or pustring error. */
843 	if (r < 0)
844 		return (-1);
845 
846 	if (msg->lm_mode == L9P_PACK) {
847 		/* Rewind to the beginning and install size at front. */
848 		uint32_t len = (uint32_t)msg->lm_size;
849 		msg->lm_cursor_offset = 0;
850 		msg->lm_cursor_iov = 0;
851 
852 		/*
853 		 * Subtract 4 bytes from current size, becase we're
854 		 * overwriting size (rewinding message to the beginning)
855 		 * and writing again, which will increase it 4 more.
856 		 */
857 		msg->lm_size -= sizeof(uint32_t);
858 
859 		if (fcall->hdr.type == L9P_RREAD ||
860 		    fcall->hdr.type == L9P_RREADDIR)
861 			len += fcall->io.count;
862 
863 		l9p_pu32(msg, &len);
864 	}
865 
866 	return (0);
867 }
868 
869 /*
870  * Free any strings or other data malloc'ed in the process of
871  * packing or unpacking an fcall.
872  */
873 void
874 l9p_freefcall(union l9p_fcall *fcall)
875 {
876 	uint16_t i;
877 
878 	switch (fcall->hdr.type) {
879 
880 	case L9P_TVERSION:
881 	case L9P_RVERSION:
882 		free(fcall->version.version);
883 		return;
884 
885 	case L9P_TATTACH:
886 		free(fcall->tattach.aname);
887 		free(fcall->tattach.uname);
888 		return;
889 
890 	case L9P_TWALK:
891 		for (i = 0; i < fcall->twalk.nwname; i++)
892 			free(fcall->twalk.wname[i]);
893 		return;
894 
895 	case L9P_TCREATE:
896 	case L9P_TOPEN:
897 		free(fcall->tcreate.name);
898 		free(fcall->tcreate.extension);
899 		return;
900 
901 	case L9P_RSTAT:
902 		l9p_freestat(&fcall->rstat.stat);
903 		return;
904 
905 	case L9P_TWSTAT:
906 		l9p_freestat(&fcall->twstat.stat);
907 		return;
908 
909 	case L9P_TLCREATE:
910 		free(fcall->tlcreate.name);
911 		return;
912 
913 	case L9P_TSYMLINK:
914 		free(fcall->tsymlink.name);
915 		free(fcall->tsymlink.symtgt);
916 		return;
917 
918 	case L9P_TMKNOD:
919 		free(fcall->tmknod.name);
920 		return;
921 
922 	case L9P_TRENAME:
923 		free(fcall->trename.name);
924 		return;
925 
926 	case L9P_RREADLINK:
927 		free(fcall->rreadlink.target);
928 		return;
929 
930 	case L9P_TXATTRWALK:
931 		free(fcall->txattrwalk.name);
932 		return;
933 
934 	case L9P_TXATTRCREATE:
935 		free(fcall->txattrcreate.name);
936 		return;
937 
938 	case L9P_TLOCK:
939 		free(fcall->tlock.client_id);
940 		return;
941 
942 	case L9P_TGETLOCK:
943 	case L9P_RGETLOCK:
944 		free(fcall->getlock.client_id);
945 		return;
946 
947 	case L9P_TLINK:
948 		free(fcall->tlink.name);
949 		return;
950 
951 	case L9P_TMKDIR:
952 		free(fcall->tmkdir.name);
953 		return;
954 
955 	case L9P_TRENAMEAT:
956 		free(fcall->trenameat.oldname);
957 		free(fcall->trenameat.newname);
958 		return;
959 
960 	case L9P_TUNLINKAT:
961 		free(fcall->tunlinkat.name);
962 		return;
963 	}
964 }
965 
966 void
967 l9p_freestat(struct l9p_stat *stat)
968 {
969 	free(stat->name);
970 	free(stat->extension);
971 	free(stat->uid);
972 	free(stat->gid);
973 	free(stat->muid);
974 }
975 
976 uint16_t
977 l9p_sizeof_stat(struct l9p_stat *stat, enum l9p_version version)
978 {
979 	uint16_t size = L9P_WORD /* size */
980 	    + L9P_WORD /* type */
981 	    + L9P_DWORD /* dev */
982 	    + QID_SIZE /* qid */
983 	    + 3 * L9P_DWORD /* mode, atime, mtime */
984 	    + L9P_QWORD /* length */
985 	    + STRING_SIZE(stat->name)
986 	    + STRING_SIZE(stat->uid)
987 	    + STRING_SIZE(stat->gid)
988 	    + STRING_SIZE(stat->muid);
989 
990 	if (version >= L9P_2000U) {
991 		size += STRING_SIZE(stat->extension)
992 		    + 3 * L9P_DWORD;
993 	}
994 
995 	return (size);
996 }
997