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
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD: releng/11.0/sys/kern/subr_mchain.c 298819 2016-04-29 22:15:33Z pfg $");
32
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/sysctl.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 FEATURE(libmchain, "mchain library");
46
47 MODULE_VERSION(libmchain, 1);
48
49 #define MBERROR(format, ...) printf("%s(%d): "format, __func__ , \
50 __LINE__ , ## __VA_ARGS__)
51
52 #define MBPANIC(format, ...) printf("%s(%d): "format, __func__ , \
53 __LINE__ , ## __VA_ARGS__)
54
55 /*
56 * Various helper functions
57 */
58 int
59 mb_init(struct mbchain *mbp)
60 {
61 struct mbuf *m;
62
63 m = m_gethdr(M_WAITOK, MT_DATA);
64 m->m_len = 0;
65 mb_initm(mbp, m);
66 return (0);
67 }
68
69 void
70 mb_initm(struct mbchain *mbp, struct mbuf *m)
71 {
72 bzero(mbp, sizeof(*mbp));
73 mbp->mb_top = mbp->mb_cur = m;
74 mbp->mb_mleft = M_TRAILINGSPACE(m);
75 }
76
77 void
78 mb_done(struct mbchain *mbp)
79 {
80 if (mbp->mb_top) {
81 m_freem(mbp->mb_top);
82 mbp->mb_top = NULL;
83 }
84 }
85
86 struct mbuf *
87 mb_detach(struct mbchain *mbp)
88 {
89 struct mbuf *m;
90
91 m = mbp->mb_top;
92 mbp->mb_top = NULL;
93 return (m);
94 }
95
96 int
97 mb_fixhdr(struct mbchain *mbp)
98 {
99 return (mbp->mb_top->m_pkthdr.len = m_fixhdr(mbp->mb_top));
100 }
101
102 /*
103 * Check if object of size 'size' fit to the current position and
104 * allocate new mbuf if not. Advance pointers and increase length of mbuf(s).
105 * Return pointer to the object placeholder or NULL if any error occurred.
106 * Note: size should be <= MLEN
107 */
108 caddr_t
109 mb_reserve(struct mbchain *mbp, int size)
110 {
111 struct mbuf *m, *mn;
112 caddr_t bpos;
113
114 if (size > MLEN)
115 panic("mb_reserve: size = %d\n", size);
116 m = mbp->mb_cur;
117 if (mbp->mb_mleft < size) {
118 mn = m_get(M_WAITOK, MT_DATA);
119 mbp->mb_cur = m->m_next = mn;
120 m = mn;
121 m->m_len = 0;
122 mbp->mb_mleft = M_TRAILINGSPACE(m);
123 }
124 mbp->mb_mleft -= size;
125 mbp->mb_count += size;
126 bpos = mtod(m, caddr_t) + m->m_len;
127 m->m_len += size;
128 return (bpos);
129 }
130
131 int
132 mb_put_padbyte(struct mbchain *mbp)
133 {
134 caddr_t dst;
135 uint8_t x = 0;
136
137 dst = mtod(mbp->mb_cur, caddr_t) + mbp->mb_cur->m_len;
138
139 /* Only add padding if address is odd */
140 if ((unsigned long)dst & 1)
141 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM));
142 else
143 return (0);
144 }
145
146 int
147 mb_put_uint8(struct mbchain *mbp, uint8_t x)
148 {
149 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM));
150 }
151
152 int
153 mb_put_uint16be(struct mbchain *mbp, uint16_t x)
154 {
155 x = htobe16(x);
156 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM));
157 }
158
159 int
160 mb_put_uint16le(struct mbchain *mbp, uint16_t x)
161 {
162 x = htole16(x);
163 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM));
164 }
165
166 int
167 mb_put_uint32be(struct mbchain *mbp, uint32_t x)
168 {
169 x = htobe32(x);
170 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM));
171 }
172
173 int
174 mb_put_uint32le(struct mbchain *mbp, uint32_t x)
175 {
176 x = htole32(x);
177 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM));
178 }
179
180 int
181 mb_put_int64be(struct mbchain *mbp, int64_t x)
182 {
183 x = htobe64(x);
184 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM));
185 }
186
187 int
188 mb_put_int64le(struct mbchain *mbp, int64_t x)
189 {
190 x = htole64(x);
191 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM));
192 }
193
194 int
195 mb_put_mem(struct mbchain *mbp, c_caddr_t source, int size, int type)
196 {
197 struct mbuf *m;
198 caddr_t dst;
199 c_caddr_t src;
200 int cplen, error, mleft, count;
201 size_t srclen, dstlen;
202
203 m = mbp->mb_cur;
204 mleft = mbp->mb_mleft;
205
206 while (size > 0) {
207 if (mleft == 0) {
208 if (m->m_next == NULL)
209 m = m_getm(m, size, M_WAITOK, MT_DATA);
210 else
211 m = m->m_next;
212 mleft = M_TRAILINGSPACE(m);
213 continue;
214 }
215 cplen = mleft > size ? size : mleft;
216 srclen = dstlen = cplen;
217 dst = mtod(m, caddr_t) + m->m_len;
218 switch (type) {
219 case MB_MCUSTOM:
220 srclen = size;
221 dstlen = mleft;
222 error = mbp->mb_copy(mbp, source, dst, &srclen, &dstlen);
223 if (error)
224 return (error);
225 break;
226 case MB_MINLINE:
227 for (src = source, count = cplen; count; count--)
228 *dst++ = *src++;
229 break;
230 case MB_MSYSTEM:
231 bcopy(source, dst, cplen);
232 break;
233 case MB_MUSER:
234 error = copyin(source, dst, cplen);
235 if (error)
236 return (error);
237 break;
238 case MB_MZERO:
239 bzero(dst, cplen);
240 break;
241 }
242 size -= srclen;
243 source += srclen;
244 m->m_len += dstlen;
245 mleft -= dstlen;
246 mbp->mb_count += dstlen;
247 }
248 mbp->mb_cur = m;
249 mbp->mb_mleft = mleft;
250 return (0);
251 }
252
253 int
254 mb_put_mbuf(struct mbchain *mbp, struct mbuf *m)
255 {
256 mbp->mb_cur->m_next = m;
257 while (m) {
258 mbp->mb_count += m->m_len;
259 if (m->m_next == NULL)
260 break;
261 m = m->m_next;
262 }
263 mbp->mb_mleft = M_TRAILINGSPACE(m);
264 mbp->mb_cur = m;
265 return (0);
266 }
267
268 /*
269 * copies a uio scatter/gather list to an mbuf chain.
270 */
271 int
272 mb_put_uio(struct mbchain *mbp, struct uio *uiop, int size)
273 {
274 long left;
275 int mtype, error;
276
277 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER;
278
279 while (size > 0 && uiop->uio_resid) {
280 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
281 return (EFBIG);
282 left = uiop->uio_iov->iov_len;
283 if (left == 0) {
284 uiop->uio_iov++;
285 uiop->uio_iovcnt--;
286 continue;
287 }
288 if (left > size)
289 left = size;
290 error = mb_put_mem(mbp, uiop->uio_iov->iov_base, left, mtype);
291 if (error)
292 return (error);
293 uiop->uio_offset += left;
294 uiop->uio_resid -= left;
295 uiop->uio_iov->iov_base =
296 (char *)uiop->uio_iov->iov_base + left;
297 uiop->uio_iov->iov_len -= left;
298 size -= left;
299 }
300 return (0);
301 }
302
303 /*
304 * Routines for fetching data from an mbuf chain
305 */
306 int
307 md_init(struct mdchain *mdp)
308 {
309 struct mbuf *m;
310
311 m = m_gethdr(M_WAITOK, MT_DATA);
312 m->m_len = 0;
313 md_initm(mdp, m);
314 return (0);
315 }
316
317 void
318 md_initm(struct mdchain *mdp, struct mbuf *m)
319 {
320 bzero(mdp, sizeof(*mdp));
321 mdp->md_top = mdp->md_cur = m;
322 mdp->md_pos = mtod(m, u_char*);
323 }
324
325 void
326 md_done(struct mdchain *mdp)
327 {
328 if (mdp->md_top) {
329 m_freem(mdp->md_top);
330 mdp->md_top = NULL;
331 }
332 }
333
334 /*
335 * Append a separate mbuf chain. It is caller responsibility to prevent
336 * multiple calls to fetch/record routines.
337 */
338 void
339 md_append_record(struct mdchain *mdp, struct mbuf *top)
340 {
341 struct mbuf *m;
342
343 if (mdp->md_top == NULL) {
344 md_initm(mdp, top);
345 return;
346 }
347 m = mdp->md_top;
348 while (m->m_nextpkt)
349 m = m->m_nextpkt;
350 m->m_nextpkt = top;
351 top->m_nextpkt = NULL;
352 return;
353 }
354
355 /*
356 * Put next record in place of existing
357 */
358 int
359 md_next_record(struct mdchain *mdp)
360 {
361 struct mbuf *m;
362
363 if (mdp->md_top == NULL)
364 return (ENOENT);
365 m = mdp->md_top->m_nextpkt;
366 md_done(mdp);
367 if (m == NULL)
368 return (ENOENT);
369 md_initm(mdp, m);
370 return (0);
371 }
372
373 int
374 md_get_uint8(struct mdchain *mdp, uint8_t *x)
375 {
376 return (md_get_mem(mdp, x, 1, MB_MINLINE));
377 }
378
379 int
380 md_get_uint16(struct mdchain *mdp, uint16_t *x)
381 {
382 return (md_get_mem(mdp, (caddr_t)x, 2, MB_MINLINE));
383 }
384
385 int
386 md_get_uint16le(struct mdchain *mdp, uint16_t *x)
387 {
388 uint16_t v;
389 int error = md_get_uint16(mdp, &v);
390
391 if (x != NULL)
392 *x = le16toh(v);
393 return (error);
394 }
395
396 int
397 md_get_uint16be(struct mdchain *mdp, uint16_t *x)
398 {
399 uint16_t v;
400 int error = md_get_uint16(mdp, &v);
401
402 if (x != NULL)
403 *x = be16toh(v);
404 return (error);
405 }
406
407 int
408 md_get_uint32(struct mdchain *mdp, uint32_t *x)
409 {
410 return (md_get_mem(mdp, (caddr_t)x, 4, MB_MINLINE));
411 }
412
413 int
414 md_get_uint32be(struct mdchain *mdp, uint32_t *x)
415 {
416 uint32_t v;
417 int error;
418
419 error = md_get_uint32(mdp, &v);
420 if (x != NULL)
421 *x = be32toh(v);
422 return (error);
423 }
424
425 int
426 md_get_uint32le(struct mdchain *mdp, uint32_t *x)
427 {
428 uint32_t v;
429 int error;
430
431 error = md_get_uint32(mdp, &v);
432 if (x != NULL)
433 *x = le32toh(v);
434 return (error);
435 }
436
437 int
438 md_get_int64(struct mdchain *mdp, int64_t *x)
439 {
440 return (md_get_mem(mdp, (caddr_t)x, 8, MB_MINLINE));
441 }
442
443 int
444 md_get_int64be(struct mdchain *mdp, int64_t *x)
445 {
446 int64_t v;
447 int error;
448
449 error = md_get_int64(mdp, &v);
450 if (x != NULL)
451 *x = be64toh(v);
452 return (error);
453 }
454
455 int
456 md_get_int64le(struct mdchain *mdp, int64_t *x)
457 {
458 int64_t v;
459 int error;
460
461 error = md_get_int64(mdp, &v);
462 if (x != NULL)
463 *x = le64toh(v);
464 return (error);
465 }
466
467 int
468 md_get_mem(struct mdchain *mdp, caddr_t target, int size, int type)
469 {
470 struct mbuf *m = mdp->md_cur;
471 int error;
472 u_int count;
473 u_char *s;
474
475 while (size > 0) {
476 if (m == NULL) {
477 MBERROR("incomplete copy\n");
478 return (EBADRPC);
479 }
480 s = mdp->md_pos;
481 count = mtod(m, u_char*) + m->m_len - s;
482 if (count == 0) {
483 mdp->md_cur = m = m->m_next;
484 if (m)
485 s = mdp->md_pos = mtod(m, caddr_t);
486 continue;
487 }
488 if (count > size)
489 count = size;
490 size -= count;
491 mdp->md_pos += count;
492 if (target == NULL)
493 continue;
494 switch (type) {
495 case MB_MUSER:
496 error = copyout(s, target, count);
497 if (error)
498 return error;
499 break;
500 case MB_MSYSTEM:
501 bcopy(s, target, count);
502 break;
503 case MB_MINLINE:
504 while (count--)
505 *target++ = *s++;
506 continue;
507 }
508 target += count;
509 }
510 return (0);
511 }
512
513 int
514 md_get_mbuf(struct mdchain *mdp, int size, struct mbuf **ret)
515 {
516 struct mbuf *m = mdp->md_cur, *rm;
517
518 rm = m_copym(m, mdp->md_pos - mtod(m, u_char*), size, M_WAITOK);
519 md_get_mem(mdp, NULL, size, MB_MZERO);
520 *ret = rm;
521 return (0);
522 }
523
524 int
525 md_get_uio(struct mdchain *mdp, struct uio *uiop, int size)
526 {
527 char *uiocp;
528 long left;
529 int mtype, error;
530
531 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER;
532 while (size > 0 && uiop->uio_resid) {
533 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL)
534 return (EFBIG);
535 left = uiop->uio_iov->iov_len;
536 if (left == 0) {
537 uiop->uio_iov++;
538 uiop->uio_iovcnt--;
539 continue;
540 }
541 uiocp = uiop->uio_iov->iov_base;
542 if (left > size)
543 left = size;
544 error = md_get_mem(mdp, uiocp, left, mtype);
545 if (error)
546 return (error);
547 uiop->uio_offset += left;
548 uiop->uio_resid -= left;
549 uiop->uio_iov->iov_base =
550 (char *)uiop->uio_iov->iov_base + left;
551 uiop->uio_iov->iov_len -= left;
552 size -= left;
553 }
554 return (0);
555 }
Cache object: 142160cc5bd535828c25bebdc2fe6c08
|