1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2000, 2001 Boris Popov 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the author nor the names of any co-contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/sysctl.h> 38 #include <sys/endian.h> 39 #include <sys/errno.h> 40 #include <sys/malloc.h> 41 #include <sys/mbuf.h> 42 #include <sys/module.h> 43 #include <sys/uio.h> 44 45 #include <sys/mchain.h> 46 47 FEATURE(libmchain, "mchain library"); 48 49 MODULE_VERSION(libmchain, 1); 50 51 #define MBERROR(format, ...) printf("%s(%d): "format, __func__ , \ 52 __LINE__ , ## __VA_ARGS__) 53 54 #define MBPANIC(format, ...) printf("%s(%d): "format, __func__ , \ 55 __LINE__ , ## __VA_ARGS__) 56 57 /* 58 * Various helper functions 59 */ 60 int 61 mb_init(struct mbchain *mbp) 62 { 63 struct mbuf *m; 64 65 m = m_gethdr(M_WAITOK, MT_DATA); 66 m->m_len = 0; 67 mb_initm(mbp, m); 68 return (0); 69 } 70 71 void 72 mb_initm(struct mbchain *mbp, struct mbuf *m) 73 { 74 bzero(mbp, sizeof(*mbp)); 75 mbp->mb_top = mbp->mb_cur = m; 76 mbp->mb_mleft = M_TRAILINGSPACE(m); 77 } 78 79 void 80 mb_done(struct mbchain *mbp) 81 { 82 if (mbp->mb_top) { 83 m_freem(mbp->mb_top); 84 mbp->mb_top = NULL; 85 } 86 } 87 88 struct mbuf * 89 mb_detach(struct mbchain *mbp) 90 { 91 struct mbuf *m; 92 93 m = mbp->mb_top; 94 mbp->mb_top = NULL; 95 return (m); 96 } 97 98 int 99 mb_fixhdr(struct mbchain *mbp) 100 { 101 return (mbp->mb_top->m_pkthdr.len = m_fixhdr(mbp->mb_top)); 102 } 103 104 /* 105 * Check if object of size 'size' fit to the current position and 106 * allocate new mbuf if not. Advance pointers and increase length of mbuf(s). 107 * Return pointer to the object placeholder or NULL if any error occurred. 108 * Note: size should be <= MLEN 109 */ 110 caddr_t 111 mb_reserve(struct mbchain *mbp, int size) 112 { 113 struct mbuf *m, *mn; 114 caddr_t bpos; 115 116 if (size > MLEN) 117 panic("mb_reserve: size = %d\n", size); 118 m = mbp->mb_cur; 119 if (mbp->mb_mleft < size) { 120 mn = m_get(M_WAITOK, MT_DATA); 121 mbp->mb_cur = m->m_next = mn; 122 m = mn; 123 m->m_len = 0; 124 mbp->mb_mleft = M_TRAILINGSPACE(m); 125 } 126 mbp->mb_mleft -= size; 127 mbp->mb_count += size; 128 bpos = mtod(m, caddr_t) + m->m_len; 129 m->m_len += size; 130 return (bpos); 131 } 132 133 int 134 mb_put_padbyte(struct mbchain *mbp) 135 { 136 caddr_t dst; 137 uint8_t x = 0; 138 139 dst = mtod(mbp->mb_cur, caddr_t) + mbp->mb_cur->m_len; 140 141 /* Only add padding if address is odd */ 142 if ((unsigned long)dst & 1) 143 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM)); 144 else 145 return (0); 146 } 147 148 int 149 mb_put_uint8(struct mbchain *mbp, uint8_t x) 150 { 151 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM)); 152 } 153 154 int 155 mb_put_uint16be(struct mbchain *mbp, uint16_t x) 156 { 157 x = htobe16(x); 158 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM)); 159 } 160 161 int 162 mb_put_uint16le(struct mbchain *mbp, uint16_t x) 163 { 164 x = htole16(x); 165 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM)); 166 } 167 168 int 169 mb_put_uint32be(struct mbchain *mbp, uint32_t x) 170 { 171 x = htobe32(x); 172 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM)); 173 } 174 175 int 176 mb_put_uint32le(struct mbchain *mbp, uint32_t x) 177 { 178 x = htole32(x); 179 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM)); 180 } 181 182 int 183 mb_put_int64be(struct mbchain *mbp, int64_t x) 184 { 185 x = htobe64(x); 186 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM)); 187 } 188 189 int 190 mb_put_int64le(struct mbchain *mbp, int64_t x) 191 { 192 x = htole64(x); 193 return (mb_put_mem(mbp, (caddr_t)&x, sizeof(x), MB_MSYSTEM)); 194 } 195 196 int 197 mb_put_mem(struct mbchain *mbp, c_caddr_t source, int size, int type) 198 { 199 struct mbuf *m; 200 caddr_t dst; 201 c_caddr_t src; 202 int cplen, error, mleft, count; 203 size_t srclen, dstlen; 204 205 m = mbp->mb_cur; 206 mleft = mbp->mb_mleft; 207 208 while (size > 0) { 209 if (mleft == 0) { 210 if (m->m_next == NULL) 211 m = m_getm(m, size, M_WAITOK, MT_DATA); 212 else 213 m = m->m_next; 214 mleft = M_TRAILINGSPACE(m); 215 continue; 216 } 217 cplen = mleft > size ? size : mleft; 218 srclen = dstlen = cplen; 219 dst = mtod(m, caddr_t) + m->m_len; 220 switch (type) { 221 case MB_MCUSTOM: 222 srclen = size; 223 dstlen = mleft; 224 error = mbp->mb_copy(mbp, source, dst, &srclen, &dstlen); 225 if (error) 226 return (error); 227 break; 228 case MB_MINLINE: 229 for (src = source, count = cplen; count; count--) 230 *dst++ = *src++; 231 break; 232 case MB_MSYSTEM: 233 bcopy(source, dst, cplen); 234 break; 235 case MB_MUSER: 236 error = copyin(source, dst, cplen); 237 if (error) 238 return (error); 239 break; 240 case MB_MZERO: 241 bzero(dst, cplen); 242 break; 243 } 244 size -= srclen; 245 source += srclen; 246 m->m_len += dstlen; 247 mleft -= dstlen; 248 mbp->mb_count += dstlen; 249 } 250 mbp->mb_cur = m; 251 mbp->mb_mleft = mleft; 252 return (0); 253 } 254 255 int 256 mb_put_mbuf(struct mbchain *mbp, struct mbuf *m) 257 { 258 mbp->mb_cur->m_next = m; 259 while (m) { 260 mbp->mb_count += m->m_len; 261 if (m->m_next == NULL) 262 break; 263 m = m->m_next; 264 } 265 mbp->mb_mleft = M_TRAILINGSPACE(m); 266 mbp->mb_cur = m; 267 return (0); 268 } 269 270 /* 271 * copies a uio scatter/gather list to an mbuf chain. 272 */ 273 int 274 mb_put_uio(struct mbchain *mbp, struct uio *uiop, int size) 275 { 276 long left; 277 int mtype, error; 278 279 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER; 280 281 while (size > 0 && uiop->uio_resid) { 282 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL) 283 return (EFBIG); 284 left = uiop->uio_iov->iov_len; 285 if (left == 0) { 286 uiop->uio_iov++; 287 uiop->uio_iovcnt--; 288 continue; 289 } 290 if (left > size) 291 left = size; 292 error = mb_put_mem(mbp, uiop->uio_iov->iov_base, left, mtype); 293 if (error) 294 return (error); 295 uiop->uio_offset += left; 296 uiop->uio_resid -= left; 297 uiop->uio_iov->iov_base = 298 (char *)uiop->uio_iov->iov_base + left; 299 uiop->uio_iov->iov_len -= left; 300 size -= left; 301 } 302 return (0); 303 } 304 305 /* 306 * Routines for fetching data from an mbuf chain 307 */ 308 int 309 md_init(struct mdchain *mdp) 310 { 311 struct mbuf *m; 312 313 m = m_gethdr(M_WAITOK, MT_DATA); 314 m->m_len = 0; 315 md_initm(mdp, m); 316 return (0); 317 } 318 319 void 320 md_initm(struct mdchain *mdp, struct mbuf *m) 321 { 322 bzero(mdp, sizeof(*mdp)); 323 mdp->md_top = mdp->md_cur = m; 324 mdp->md_pos = mtod(m, u_char*); 325 } 326 327 void 328 md_done(struct mdchain *mdp) 329 { 330 if (mdp->md_top) { 331 m_freem(mdp->md_top); 332 mdp->md_top = NULL; 333 } 334 } 335 336 /* 337 * Append a separate mbuf chain. It is caller responsibility to prevent 338 * multiple calls to fetch/record routines. 339 */ 340 void 341 md_append_record(struct mdchain *mdp, struct mbuf *top) 342 { 343 struct mbuf *m; 344 345 if (mdp->md_top == NULL) { 346 md_initm(mdp, top); 347 return; 348 } 349 m = mdp->md_top; 350 while (m->m_nextpkt) 351 m = m->m_nextpkt; 352 m->m_nextpkt = top; 353 top->m_nextpkt = NULL; 354 return; 355 } 356 357 /* 358 * Put next record in place of existing 359 */ 360 int 361 md_next_record(struct mdchain *mdp) 362 { 363 struct mbuf *m; 364 365 if (mdp->md_top == NULL) 366 return (ENOENT); 367 m = mdp->md_top->m_nextpkt; 368 md_done(mdp); 369 if (m == NULL) 370 return (ENOENT); 371 md_initm(mdp, m); 372 return (0); 373 } 374 375 int 376 md_get_uint8(struct mdchain *mdp, uint8_t *x) 377 { 378 return (md_get_mem(mdp, x, 1, MB_MINLINE)); 379 } 380 381 int 382 md_get_uint16(struct mdchain *mdp, uint16_t *x) 383 { 384 return (md_get_mem(mdp, (caddr_t)x, 2, MB_MINLINE)); 385 } 386 387 int 388 md_get_uint16le(struct mdchain *mdp, uint16_t *x) 389 { 390 uint16_t v; 391 int error = md_get_uint16(mdp, &v); 392 393 if (x != NULL) 394 *x = le16toh(v); 395 return (error); 396 } 397 398 int 399 md_get_uint16be(struct mdchain *mdp, uint16_t *x) 400 { 401 uint16_t v; 402 int error = md_get_uint16(mdp, &v); 403 404 if (x != NULL) 405 *x = be16toh(v); 406 return (error); 407 } 408 409 int 410 md_get_uint32(struct mdchain *mdp, uint32_t *x) 411 { 412 return (md_get_mem(mdp, (caddr_t)x, 4, MB_MINLINE)); 413 } 414 415 int 416 md_get_uint32be(struct mdchain *mdp, uint32_t *x) 417 { 418 uint32_t v; 419 int error; 420 421 error = md_get_uint32(mdp, &v); 422 if (x != NULL) 423 *x = be32toh(v); 424 return (error); 425 } 426 427 int 428 md_get_uint32le(struct mdchain *mdp, uint32_t *x) 429 { 430 uint32_t v; 431 int error; 432 433 error = md_get_uint32(mdp, &v); 434 if (x != NULL) 435 *x = le32toh(v); 436 return (error); 437 } 438 439 int 440 md_get_int64(struct mdchain *mdp, int64_t *x) 441 { 442 return (md_get_mem(mdp, (caddr_t)x, 8, MB_MINLINE)); 443 } 444 445 int 446 md_get_int64be(struct mdchain *mdp, int64_t *x) 447 { 448 int64_t v; 449 int error; 450 451 error = md_get_int64(mdp, &v); 452 if (x != NULL) 453 *x = be64toh(v); 454 return (error); 455 } 456 457 int 458 md_get_int64le(struct mdchain *mdp, int64_t *x) 459 { 460 int64_t v; 461 int error; 462 463 error = md_get_int64(mdp, &v); 464 if (x != NULL) 465 *x = le64toh(v); 466 return (error); 467 } 468 469 int 470 md_get_mem(struct mdchain *mdp, caddr_t target, int size, int type) 471 { 472 struct mbuf *m = mdp->md_cur; 473 int error; 474 u_int count; 475 u_char *s; 476 477 while (size > 0) { 478 if (m == NULL) { 479 MBERROR("incomplete copy\n"); 480 return (EBADRPC); 481 } 482 s = mdp->md_pos; 483 count = mtod(m, u_char*) + m->m_len - s; 484 if (count == 0) { 485 mdp->md_cur = m = m->m_next; 486 if (m) 487 s = mdp->md_pos = mtod(m, caddr_t); 488 continue; 489 } 490 if (count > size) 491 count = size; 492 size -= count; 493 mdp->md_pos += count; 494 if (target == NULL) 495 continue; 496 switch (type) { 497 case MB_MUSER: 498 error = copyout(s, target, count); 499 if (error) 500 return error; 501 break; 502 case MB_MSYSTEM: 503 bcopy(s, target, count); 504 break; 505 case MB_MINLINE: 506 while (count--) 507 *target++ = *s++; 508 continue; 509 } 510 target += count; 511 } 512 return (0); 513 } 514 515 int 516 md_get_mbuf(struct mdchain *mdp, int size, struct mbuf **ret) 517 { 518 struct mbuf *m = mdp->md_cur, *rm; 519 520 rm = m_copym(m, mdp->md_pos - mtod(m, u_char*), size, M_WAITOK); 521 md_get_mem(mdp, NULL, size, MB_MZERO); 522 *ret = rm; 523 return (0); 524 } 525 526 int 527 md_get_uio(struct mdchain *mdp, struct uio *uiop, int size) 528 { 529 char *uiocp; 530 long left; 531 int mtype, error; 532 533 mtype = (uiop->uio_segflg == UIO_SYSSPACE) ? MB_MSYSTEM : MB_MUSER; 534 while (size > 0 && uiop->uio_resid) { 535 if (uiop->uio_iovcnt <= 0 || uiop->uio_iov == NULL) 536 return (EFBIG); 537 left = uiop->uio_iov->iov_len; 538 if (left == 0) { 539 uiop->uio_iov++; 540 uiop->uio_iovcnt--; 541 continue; 542 } 543 uiocp = uiop->uio_iov->iov_base; 544 if (left > size) 545 left = size; 546 error = md_get_mem(mdp, uiocp, left, mtype); 547 if (error) 548 return (error); 549 uiop->uio_offset += left; 550 uiop->uio_resid -= left; 551 uiop->uio_iov->iov_base = 552 (char *)uiop->uio_iov->iov_base + left; 553 uiop->uio_iov->iov_len -= left; 554 size -= left; 555 } 556 return (0); 557 } 558