1 /*
2 * Copyright (c) 2000, 2001 Boris Popov
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided 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 * 4. Neither the name of the author nor the names of any co-contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: src/sys/kern/subr_mchain.c,v 1.2.2.2 2002/04/13 12:46:40 bp Exp $
30 */
31
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/kernel.h>
36 #include <sys/endian.h>
37 #include <sys/errno.h>
38 #include <sys/malloc.h>
39 #include <sys/mbuf.h>
40 #include <sys/module.h>
41 #include <sys/uio.h>
42
43 #include <sys/mchain.h>
44
45 MODULE_VERSION(libmchain, 1);
46
47 #define MBERROR(format, ...) kprintf("%s(%d): "format, __func__ , \
48 __LINE__ , ## __VA_ARGS__)
49
50 #define MBPANIC(format, ...) kprintf("%s(%d): "format, __func__ , \
51 __LINE__ , ## __VA_ARGS__)
52
53 /*
54 * Various helper functions
55 */
56 int
m_fixhdr(struct mbuf * m0)57 m_fixhdr(struct mbuf *m0)
58 {
59 struct mbuf *m = m0;
60 int len = 0;
61
62 while (m) {
63 len += m->m_len;
64 m = m->m_next;
65 }
66 m0->m_pkthdr.len = len;
67 return len;
68 }
69
70 int
mb_init(struct mbchain * mbp)71 mb_init(struct mbchain *mbp)
72 {
73 struct mbuf *m;
74
75 m = m_gethdr(M_WAITOK, MT_DATA);
76 m->m_pkthdr.rcvif = NULL;
77 m->m_len = 0;
78 mb_initm(mbp, m);
79 return 0;
80 }
81
82 void
mb_initm(struct mbchain * mbp,struct mbuf * m)83 mb_initm(struct mbchain *mbp, struct mbuf *m)
84 {
85 bzero(mbp, sizeof(*mbp));
86 mbp->mb_top = mbp->mb_cur = m;
87 mbp->mb_mleft = M_TRAILINGSPACE(m);
88 }
89
90 void
mb_done(struct mbchain * mbp)91 mb_done(struct mbchain *mbp)
92 {
93 if (mbp->mb_top) {
94 m_freem(mbp->mb_top);
95 mbp->mb_top = NULL;
96 }
97 }
98
99 struct mbuf *
mb_detach(struct mbchain * mbp)100 mb_detach(struct mbchain *mbp)
101 {
102 struct mbuf *m;
103
104 m = mbp->mb_top;
105 mbp->mb_top = NULL;
106 return m;
107 }
108
109 int
mb_fixhdr(struct mbchain * mbp)110 mb_fixhdr(struct mbchain *mbp)
111 {
112 return mbp->mb_top->m_pkthdr.len = m_fixhdr(mbp->mb_top);
113 }
114
115 /*
116 * Check if object of size 'size' fit to the current position and
117 * allocate new mbuf if not. Advance pointers and increase length of mbuf(s).
118 * Return pointer to the object placeholder or NULL if any error occured.
119 * Note: size should be <= MLEN
120 */
121 caddr_t
mb_reserve(struct mbchain * mbp,int size)122 mb_reserve(struct mbchain *mbp, int size)
123 {
124 struct mbuf *m, *mn;
125 caddr_t bpos;
126
127 if (size > MLEN)
128 panic("mb_reserve: size = %d", size);
129 m = mbp->mb_cur;
130 if (mbp->mb_mleft < size) {
131 mn = m_get(M_WAITOK, MT_DATA);
132 mbp->mb_cur = m->m_next = mn;
133 m = mn;
134 m->m_len = 0;
135 mbp->mb_mleft = M_TRAILINGSPACE(m);
136 }
137 mbp->mb_mleft -= size;
138 mbp->mb_count += size;
139 bpos = mtod(m, caddr_t) + m->m_len;
140 m->m_len += size;
141 return bpos;
142 }
143
144 int
mb_put_uint8(struct mbchain * mbp,u_int8_t x)145 mb_put_uint8(struct mbchain *mbp, u_int8_t x)
146 {
147 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
148 }
149
150 int
mb_put_uint16be(struct mbchain * mbp,u_int16_t x)151 mb_put_uint16be(struct mbchain *mbp, u_int16_t x)
152 {
153 x = htobe16(x);
154 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
155 }
156
157 int
mb_put_uint16le(struct mbchain * mbp,u_int16_t x)158 mb_put_uint16le(struct mbchain *mbp, u_int16_t x)
159 {
160 x = htole16(x);
161 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
162 }
163
164 int
mb_put_uint32be(struct mbchain * mbp,u_int32_t x)165 mb_put_uint32be(struct mbchain *mbp, u_int32_t x)
166 {
167 x = htobe32(x);
168 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
169 }
170
171 int
mb_put_uint32le(struct mbchain * mbp,u_int32_t x)172 mb_put_uint32le(struct mbchain *mbp, u_int32_t x)
173 {
174 x = htole32(x);
175 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
176 }
177
178 int
mb_put_int64be(struct mbchain * mbp,int64_t x)179 mb_put_int64be(struct mbchain *mbp, int64_t x)
180 {
181 x = htobe64(x);
182 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
183 }
184
185 int
mb_put_int64le(struct mbchain * mbp,int64_t x)186 mb_put_int64le(struct mbchain *mbp, int64_t x)
187 {
188 x = htole64(x);
189 return mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM);
190 }
191
192 int
mb_put_mem(struct mbchain * mbp,c_caddr_t source,int size,int type)193 mb_put_mem(struct mbchain *mbp, c_caddr_t source, int size, int type)
194 {
195 struct mbuf *m;
196 caddr_t dst;
197 c_caddr_t src;
198 int error, mleft, count;
199 size_t cplen, srclen, dstlen;
200
201 m = mbp->mb_cur;
202 mleft = mbp->mb_mleft;
203
204 while (size > 0) {
205 if (mleft == 0) {
206 if (m->m_next == NULL)
207 m->m_next = m_getc(size, M_WAITOK, MT_DATA);
208 m = m->m_next;
209 mleft = M_TRAILINGSPACE(m);
210 continue;
211 }
212 cplen = mleft > size ? size : mleft;
213 srclen = dstlen = cplen;
214 dst = mtod(m, caddr_t) + m->m_len;
215 switch (type) {
216 case MB_MCUSTOM:
217 srclen = size;
218 dstlen = mleft;
219 error = mbp->mb_copy(mbp, source, dst, &srclen, &dstlen);
220 if (error)
221 return error;
222 break;
223 case MB_MINLINE:
224 for (src = source, count = cplen; count; count--)
225 *dst++ = *src++;
226 break;
227 case MB_MSYSTEM:
228 bcopy(source, dst, cplen);
229 break;
230 case MB_MUSER:
231 error = copyin(source, dst, cplen);
232 if (error)
233 return error;
234 break;
235 case MB_MZERO:
236 bzero(dst, cplen);
237 break;
238 }
239 size -= srclen;
240 source += srclen;
241 m->m_len += dstlen;
242 mleft -= dstlen;
243 mbp->mb_count += dstlen;
244 }
245 mbp->mb_cur = m;
246 mbp->mb_mleft = mleft;
247 return 0;
248 }
249
250 int
mb_put_mbuf(struct mbchain * mbp,struct mbuf * m)251 mb_put_mbuf(struct mbchain *mbp, struct mbuf *m)
252 {
253 mbp->mb_cur->m_next = m;
254 while (m) {
255 mbp->mb_count += m->m_len;
256 if (m->m_next == NULL)
257 break;
258 m = m->m_next;
259 }
260 mbp->mb_mleft = M_TRAILINGSPACE(m);
261 mbp->mb_cur = m;
262 return 0;
263 }
264
265 /*
266 * copies a uio scatter/gather list to an mbuf chain.
267 */
268 int
mb_put_uio(struct mbchain * mbp,struct uio * uiop,int size)269 mb_put_uio(struct mbchain *mbp, struct uio *uiop, int size)
270 {
271 long left;
272 int mtype, error;
273
274 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER;
275
276 while (size > 0 && uiop->uio_resid) {
277 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
278 return EFBIG;
279 left = uiop->uio_iov->iov_len;
280 if (left == 0) {
281 uiop->uio_iov++;
282 uiop->uio_iovcnt--;
283 continue;
284 }
285 if (left > size)
286 left = size;
287 error = mb_put_mem(mbp, uiop->uio_iov->iov_base, left, mtype);
288 if (error)
289 return error;
290 uiop->uio_offset += left;
291 uiop->uio_resid -= left;
292 uiop->uio_iov->iov_base =
293 (char *)uiop->uio_iov->iov_base + left;
294 uiop->uio_iov->iov_len -= left;
295 size -= left;
296 }
297 return 0;
298 }
299
300 /*
301 * Routines for fetching data from an mbuf chain
302 */
303 int
md_init(struct mdchain * mdp)304 md_init(struct mdchain *mdp)
305 {
306 struct mbuf *m;
307
308 m = m_gethdr(M_WAITOK, MT_DATA);
309 m->m_pkthdr.rcvif = NULL;
310 m->m_len = 0;
311 md_initm(mdp, m);
312 return 0;
313 }
314
315 void
md_initm(struct mdchain * mdp,struct mbuf * m)316 md_initm(struct mdchain *mdp, struct mbuf *m)
317 {
318 bzero(mdp, sizeof(*mdp));
319 mdp->md_top = mdp->md_cur = m;
320 mdp->md_pos = mtod(m, u_char*);
321 }
322
323 void
md_done(struct mdchain * mdp)324 md_done(struct mdchain *mdp)
325 {
326 if (mdp->md_top) {
327 m_freem(mdp->md_top);
328 mdp->md_top = NULL;
329 }
330 }
331
332 /*
333 * Append a separate mbuf chain. It is caller responsibility to prevent
334 * multiple calls to fetch/record routines.
335 */
336 void
md_append_record(struct mdchain * mdp,struct mbuf * top)337 md_append_record(struct mdchain *mdp, struct mbuf *top)
338 {
339 struct mbuf *m;
340
341 if (mdp->md_top == NULL) {
342 md_initm(mdp, top);
343 return;
344 }
345 m = mdp->md_top;
346 while (m->m_nextpkt)
347 m = m->m_nextpkt;
348 m->m_nextpkt = top;
349 top->m_nextpkt = NULL;
350 return;
351 }
352
353 /*
354 * Put next record in place of existing
355 */
356 int
md_next_record(struct mdchain * mdp)357 md_next_record(struct mdchain *mdp)
358 {
359 struct mbuf *m;
360
361 if (mdp->md_top == NULL)
362 return ENOENT;
363 m = mdp->md_top->m_nextpkt;
364 md_done(mdp);
365 if (m == NULL)
366 return ENOENT;
367 md_initm(mdp, m);
368 return 0;
369 }
370
371 int
md_get_uint8(struct mdchain * mdp,u_int8_t * x)372 md_get_uint8(struct mdchain *mdp, u_int8_t *x)
373 {
374 return md_get_mem(mdp, x, 1, MB_MINLINE);
375 }
376
377 int
md_get_uint16(struct mdchain * mdp,u_int16_t * x)378 md_get_uint16(struct mdchain *mdp, u_int16_t *x)
379 {
380 return md_get_mem(mdp, (caddr_t)x, 2, MB_MINLINE);
381 }
382
383 int
md_get_uint16le(struct mdchain * mdp,u_int16_t * x)384 md_get_uint16le(struct mdchain *mdp, u_int16_t *x)
385 {
386 u_int16_t v;
387 int error = md_get_uint16(mdp, &v);
388
389 if (x != NULL)
390 *x = le16toh(v);
391 return error;
392 }
393
394 int
md_get_uint16be(struct mdchain * mdp,u_int16_t * x)395 md_get_uint16be(struct mdchain *mdp, u_int16_t *x) {
396 u_int16_t v;
397 int error = md_get_uint16(mdp, &v);
398
399 if (x != NULL)
400 *x = be16toh(v);
401 return error;
402 }
403
404 int
md_get_uint32(struct mdchain * mdp,u_int32_t * x)405 md_get_uint32(struct mdchain *mdp, u_int32_t *x)
406 {
407 return md_get_mem(mdp, (caddr_t)x, 4, MB_MINLINE);
408 }
409
410 int
md_get_uint32be(struct mdchain * mdp,u_int32_t * x)411 md_get_uint32be(struct mdchain *mdp, u_int32_t *x)
412 {
413 u_int32_t v;
414 int error;
415
416 error = md_get_uint32(mdp, &v);
417 if (x != NULL)
418 *x = be32toh(v);
419 return error;
420 }
421
422 int
md_get_uint32le(struct mdchain * mdp,u_int32_t * x)423 md_get_uint32le(struct mdchain *mdp, u_int32_t *x)
424 {
425 u_int32_t v;
426 int error;
427
428 error = md_get_uint32(mdp, &v);
429 if (x != NULL)
430 *x = le32toh(v);
431 return error;
432 }
433
434 int
md_get_int64(struct mdchain * mdp,int64_t * x)435 md_get_int64(struct mdchain *mdp, int64_t *x)
436 {
437 return md_get_mem(mdp, (caddr_t)x, 8, MB_MINLINE);
438 }
439
440 int
md_get_int64be(struct mdchain * mdp,int64_t * x)441 md_get_int64be(struct mdchain *mdp, int64_t *x)
442 {
443 int64_t v;
444 int error;
445
446 error = md_get_int64(mdp, &v);
447 if (x != NULL)
448 *x = be64toh(v);
449 return error;
450 }
451
452 int
md_get_int64le(struct mdchain * mdp,int64_t * x)453 md_get_int64le(struct mdchain *mdp, int64_t *x)
454 {
455 int64_t v;
456 int error;
457
458 error = md_get_int64(mdp, &v);
459 if (x != NULL)
460 *x = le64toh(v);
461 return error;
462 }
463
464 int
md_get_mem(struct mdchain * mdp,caddr_t target,int size,int type)465 md_get_mem(struct mdchain *mdp, caddr_t target, int size, int type)
466 {
467 struct mbuf *m = mdp->md_cur;
468 int error;
469 u_int count;
470 u_char *s;
471
472 while (size > 0) {
473 if (m == NULL) {
474 MBERROR("incomplete copy\n");
475 return EBADRPC;
476 }
477 s = mdp->md_pos;
478 count = mtod(m, u_char*) + m->m_len - s;
479 if (count == 0) {
480 mdp->md_cur = m = m->m_next;
481 if (m)
482 s = mdp->md_pos = mtod(m, caddr_t);
483 continue;
484 }
485 if (count > size)
486 count = size;
487 size -= count;
488 mdp->md_pos += count;
489 if (target == NULL)
490 continue;
491 switch (type) {
492 case MB_MUSER:
493 error = copyout(s, target, count);
494 if (error)
495 return error;
496 break;
497 case MB_MSYSTEM:
498 bcopy(s, target, count);
499 break;
500 case MB_MINLINE:
501 while (count--)
502 *target++ = *s++;
503 continue;
504 }
505 target += count;
506 }
507 return 0;
508 }
509
510 int
md_get_mbuf(struct mdchain * mdp,int size,struct mbuf ** ret)511 md_get_mbuf(struct mdchain *mdp, int size, struct mbuf **ret)
512 {
513 struct mbuf *m = mdp->md_cur, *rm;
514
515 rm = m_copym(m, mdp->md_pos - mtod(m, u_char*), size, M_WAITOK);
516 if (rm == NULL)
517 return EBADRPC;
518 md_get_mem(mdp, NULL, size, MB_MZERO);
519 *ret = rm;
520 return 0;
521 }
522
523 int
md_get_uio(struct mdchain * mdp,struct uio * uiop,int size)524 md_get_uio(struct mdchain *mdp, struct uio *uiop, int size)
525 {
526 char *uiocp;
527 long left;
528 int mtype, error;
529
530 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER;
531 while (size > 0 && uiop->uio_resid) {
532 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
533 return EFBIG;
534 left = uiop->uio_iov->iov_len;
535 if (left == 0) {
536 uiop->uio_iov++;
537 uiop->uio_iovcnt--;
538 continue;
539 }
540 uiocp = uiop->uio_iov->iov_base;
541 if (left > size)
542 left = size;
543 error = md_get_mem(mdp, uiocp, left, mtype);
544 if (error)
545 return error;
546 uiop->uio_offset += left;
547 uiop->uio_resid -= left;
548 uiop->uio_iov->iov_base =
549 (char *)uiop->uio_iov->iov_base + left;
550 uiop->uio_iov->iov_len -= left;
551 size -= left;
552 }
553 return 0;
554 }
555