1 /* 2 * Copyright (c) 2004 The DragonFly Project. All rights reserved. 3 * 4 * Copyright (c) 1982, 1986, 1988, 1993 5 * The Regents of the University of California. 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)mbuf.h 8.5 (Berkeley) 2/19/95 36 * $FreeBSD: src/sys/sys/mbuf.h,v 1.44.2.17 2003/04/15 06:15:02 silby Exp $ 37 * $DragonFly: src/sys/sys/mbuf.h,v 1.24 2005/04/20 21:37:06 hsu Exp $ 38 */ 39 40 #ifndef _SYS_MBUF_H_ 41 #define _SYS_MBUF_H_ 42 43 #include <sys/queue.h> 44 45 /* 46 * Mbufs are of a single size, MSIZE (machine/param.h), which 47 * includes overhead. An mbuf may add a single "mbuf cluster" of size 48 * MCLBYTES (also in machine/param.h), which has no additional overhead 49 * and is used instead of the internal data area; this is done when 50 * at least MINCLSIZE of data must be stored. 51 */ 52 #define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */ 53 #define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */ 54 #define MINCLSIZE (MHLEN + 1) /* smallest amount to put in cluster */ 55 #define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */ 56 57 /* 58 * Macros for type conversion: 59 * mtod(m, t) -- Convert mbuf pointer to data pointer of correct type. 60 * mtocl(x) - convert pointer within cluster to cluster index # 61 * cltom(x) - convert cluster # to ptr to beginning of cluster 62 */ 63 #define mtod(m, t) ((t)((m)->m_data)) 64 65 /* 66 * Header present at the beginning of every mbuf. 67 */ 68 struct m_hdr { 69 struct mbuf *mh_next; /* next buffer in chain */ 70 struct mbuf *mh_nextpkt; /* next chain in queue/record */ 71 caddr_t mh_data; /* location of data */ 72 int mh_len; /* amount of data in this mbuf */ 73 short mh_type; /* type of data in this mbuf */ 74 short mh_flags; /* flags; see below */ 75 }; 76 77 /* 78 * Packet tag structure (see below for details). 79 */ 80 struct m_tag { 81 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */ 82 u_int16_t m_tag_id; /* Tag ID */ 83 u_int16_t m_tag_len; /* Length of data */ 84 u_int32_t m_tag_cookie; /* ABI/Module ID */ 85 }; 86 87 SLIST_HEAD(packet_tags, m_tag); 88 89 /* 90 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set. 91 * 92 * Be careful: The fields have been carefully ordered to avoid hidden padding. 93 * Keep this in mind, when adding or removing fields! 94 */ 95 struct pkthdr { 96 struct ifnet *rcvif; /* rcv interface */ 97 int len; /* total packet length */ 98 struct packet_tags tags; /* list of packet tags */ 99 100 /* variables for ip and tcp reassembly */ 101 void *header; /* pointer to packet header */ 102 103 /* variables for hardware checksum */ 104 int csum_flags; /* flags regarding checksum */ 105 int csum_data; /* data field used by csum routines */ 106 107 /* firewall flags */ 108 uint32_t fw_flags; /* flags for PF */ 109 110 /* variables for PF processing */ 111 uint16_t pf_tag; /* PF tag id */ 112 uint8_t pf_routed; /* PF routing counter */ 113 114 /* variables for ALTQ processing */ 115 uint8_t ecn_af; /* address family for ECN */ 116 uint32_t altq_qid; /* queue id */ 117 }; 118 119 /* 120 * Description of external storage mapped into mbuf; valid only if M_EXT is set. 121 */ 122 struct m_ext { 123 caddr_t ext_buf; /* start of buffer */ 124 union { 125 void (*old)(caddr_t, u_int); 126 void (*new)(void *arg); 127 void *any; 128 } ext_nfree; 129 u_int ext_size; /* size of buffer, for ext_nfree */ 130 union { 131 void (*old)(caddr_t, u_int); 132 void (*new)(void *arg); 133 void *any; 134 } ext_nref; 135 void *ext_arg; 136 }; 137 138 /* 139 * The core of the mbuf object along with some shortcut defines for 140 * practical purposes. 141 */ 142 struct mbuf { 143 struct m_hdr m_hdr; 144 union { 145 struct { 146 struct pkthdr MH_pkthdr; /* M_PKTHDR set */ 147 union { 148 struct m_ext MH_ext; /* M_EXT set */ 149 char MH_databuf[MHLEN]; 150 } MH_dat; 151 } MH; 152 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */ 153 } M_dat; 154 }; 155 #define m_next m_hdr.mh_next 156 #define m_len m_hdr.mh_len 157 #define m_data m_hdr.mh_data 158 #define m_type m_hdr.mh_type 159 #define m_flags m_hdr.mh_flags 160 #define m_nextpkt m_hdr.mh_nextpkt 161 #define m_pkthdr M_dat.MH.MH_pkthdr 162 #define m_ext M_dat.MH.MH_dat.MH_ext 163 #define m_pktdat M_dat.MH.MH_dat.MH_databuf 164 #define m_dat M_dat.M_databuf 165 166 /* 167 * Code that uses m_act should be converted to use m_nextpkt 168 * instead; m_act is historical and deprecated. 169 */ 170 #define m_act m_nextpkt 171 172 /* 173 * mbuf flags. 174 */ 175 #define M_EXT 0x0001 /* has associated external storage */ 176 #define M_PKTHDR 0x0002 /* start of record */ 177 #define M_EOR 0x0004 /* end of record */ 178 #define M_PROTO1 0x0008 /* protocol-specific */ 179 #define M_PROTO2 0x0010 /* protocol-specific */ 180 #define M_PROTO3 0x0020 /* protocol-specific */ 181 #define M_PROTO4 0x0040 /* protocol-specific */ 182 #define M_PROTO5 0x0080 /* protocol-specific */ 183 184 /* 185 * mbuf pkthdr flags (also stored in m_flags). 186 */ 187 #define M_BCAST 0x0100 /* send/received as link-level broadcast */ 188 #define M_MCAST 0x0200 /* send/received as link-level multicast */ 189 #define M_FRAG 0x0400 /* packet is a fragment of a larger packet */ 190 #define M_FIRSTFRAG 0x0800 /* packet is first fragment */ 191 #define M_LASTFRAG 0x1000 /* packet is last fragment */ 192 #define M_EXT_OLD 0x2000 /* new ext function format */ 193 #define M_EXT_CLUSTER 0x4000 /* standard cluster else special */ 194 195 /* 196 * Flags copied when copying m_pkthdr. 197 */ 198 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_PROTO1|M_PROTO1|M_PROTO2|M_PROTO3 | \ 199 M_PROTO4|M_PROTO5|M_BCAST|M_MCAST|M_FRAG | \ 200 M_FIRSTFRAG|M_LASTFRAG) 201 202 /* 203 * Flags indicating hw checksum support and sw checksum requirements. 204 */ 205 #define CSUM_IP 0x0001 /* will csum IP */ 206 #define CSUM_TCP 0x0002 /* will csum TCP */ 207 #define CSUM_UDP 0x0004 /* will csum UDP */ 208 #define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */ 209 #define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */ 210 211 #define CSUM_IP_CHECKED 0x0100 /* did csum IP */ 212 #define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ 213 #define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ 214 #define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ 215 216 #define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) 217 #define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */ 218 219 /* 220 * Flags indicating PF processing status 221 */ 222 #define PF_MBUF_GENERATED 0x00000001 223 #define PF_MBUF_TAGGED 0x00000002 /* pf_tag field is valid */ 224 #define PF_MBUF_ROUTED 0x00000004 /* pf_routed field is valid */ 225 #define PF_MBUF_TRANSLATE_LOCALHOST \ 226 0x00000008 227 #define PF_MBUF_FRAGCACHE 0x00000010 228 #define ALTQ_MBUF_TAGGED 0x00000020 /* altq_qid is valid */ 229 230 /* 231 * mbuf types. 232 */ 233 #define MT_FREE 0 /* should be on free list */ 234 #define MT_DATA 1 /* dynamic (data) allocation */ 235 #define MT_HEADER 2 /* packet header */ 236 #define MT_SONAME 3 /* socket name */ 237 #define MT_TAG 4 /* volatile metadata associated to pkts */ 238 #define MT_CONTROL 5 /* extra-data protocol message */ 239 #define MT_OOBDATA 6 /* expedited data */ 240 #define MT_NTYPES 7 /* number of mbuf types for mbtypes[] */ 241 242 /* 243 * General mbuf allocator statistics structure. 244 */ 245 struct mbstat { 246 u_long m_mbufs; /* mbufs obtained from page pool */ 247 u_long m_clusters; /* clusters obtained from page pool */ 248 u_long m_spare; /* spare field */ 249 u_long m_clfree; /* free clusters */ 250 u_long m_drops; /* times failed to find space */ 251 u_long m_wait; /* times waited for space */ 252 u_long m_drain; /* times drained protocols for space */ 253 u_long m_mcfail; /* times m_copym failed */ 254 u_long m_mpfail; /* times m_pullup failed */ 255 u_long m_msize; /* length of an mbuf */ 256 u_long m_mclbytes; /* length of an mbuf cluster */ 257 u_long m_minclsize; /* min length of data to allocate a cluster */ 258 u_long m_mlen; /* length of data in an mbuf */ 259 u_long m_mhlen; /* length of data in a header mbuf */ 260 }; 261 262 /* 263 * Flags specifying how an allocation should be made. 264 */ 265 266 #define MB_DONTWAIT 0x4 267 #define MB_TRYWAIT 0x8 268 #define MB_WAIT MB_TRYWAIT 269 270 /* 271 * Mbuf to Malloc Flag Conversion. 272 */ 273 #define MBTOM(how) ((how) & MB_TRYWAIT ? M_WAITOK : M_NOWAIT) 274 275 /* 276 * These are identifying numbers passed to the m_mballoc_wait function, 277 * allowing us to determine whether the call came from an MGETHDR or 278 * an MGET. 279 */ 280 #define MGETHDR_C 1 281 #define MGET_C 2 282 283 /* 284 * Wake up the next instance (if any) of m_mballoc_wait() which is 285 * waiting for an mbuf to be freed. This should be called at splimp(). 286 * 287 * XXX: If there is another free mbuf, this routine will be called [again] 288 * from the m_mballoc_wait routine in order to wake another sleep instance. 289 */ 290 #define MMBWAKEUP() do { \ 291 if (m_mballoc_wid) { \ 292 m_mballoc_wid--; \ 293 wakeup_one(&m_mballoc_wid); \ 294 } \ 295 } while (0) 296 297 /* 298 * Same as above, but for mbuf cluster(s). 299 */ 300 #define MCLWAKEUP() do { \ 301 if (m_clalloc_wid) { \ 302 m_clalloc_wid--; \ 303 wakeup_one(&m_clalloc_wid); \ 304 } \ 305 } while (0) 306 307 /* 308 * mbuf utility macros: 309 * 310 * MBUFLOCK(code) 311 * prevents a section of code from from being interrupted by network 312 * drivers. 313 */ 314 #define MBUFLOCK(code) do { \ 315 int _ms = splimp(); \ 316 \ 317 { code } \ 318 splx(_ms); \ 319 } while (0) 320 321 /* 322 * mbuf allocation/deallocation macros (YYY deprecated, too big): 323 * 324 * MGET(struct mbuf *m, int how, int type) 325 * allocates an mbuf and initializes it to contain internal data. 326 * 327 * MGETHDR(struct mbuf *m, int how, int type) 328 * allocates an mbuf and initializes it to contain a packet header 329 * and internal data. 330 */ 331 #define MGET(m, how, type) do { \ 332 (m) = m_get((how), (type)); \ 333 } while (0) 334 335 #define MGETHDR(m, how, type) do { \ 336 (m) = m_gethdr((how), (type)); \ 337 } while (0) 338 339 /* 340 * MCLGET adds such clusters to a normal mbuf. The flag M_EXT is set upon 341 * success. 342 */ 343 #define MCLGET(m, how) do { \ 344 m_mclget((m), (how)); \ 345 } while (0) 346 347 /* 348 * NB: M_COPY_PKTHDR is deprecated; use either M_MOVE_PKTHDR 349 * or m_dup_pkthdr. 350 */ 351 /* 352 * Move mbuf pkthdr from "from" to "to". 353 * from should have M_PKTHDR set, and to must be empty. 354 * from no longer has a pkthdr after this operation. 355 */ 356 #define M_MOVE_PKTHDR(_to, _from) m_move_pkthdr((_to), (_from)) 357 358 /* 359 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place 360 * an object of the specified size at the end of the mbuf, longword aligned. 361 */ 362 #define M_ALIGN(m, len) do { \ 363 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ 364 } while (0) 365 366 /* 367 * As above, for mbufs allocated with m_gethdr/MGETHDR 368 * or initialized by M_COPY_PKTHDR. 369 */ 370 #define MH_ALIGN(m, len) do { \ 371 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ 372 } while (0) 373 374 /* 375 * Check if we can write to an mbuf. 376 */ 377 #define M_EXT_WRITABLE(m) (m_sharecount(m) == 1) 378 #define M_WRITABLE(m) (!((m)->m_flags & M_EXT) || M_EXT_WRITABLE(m)) 379 380 /* 381 * Check if the supplied mbuf has a packet header, or else panic. 382 */ 383 #define M_ASSERTPKTHDR(m) \ 384 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \ 385 ("%s: invalid mbuf or no mbuf packet header!", __func__)) 386 387 /* 388 * Compute the amount of space available 389 * before the current start of data in an mbuf. 390 * 391 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 392 * of checking writability of the mbuf data area rests solely with the caller. 393 */ 394 #define M_LEADINGSPACE(m) \ 395 ((m)->m_flags & M_EXT ? \ 396 (M_EXT_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \ 397 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 398 (m)->m_data - (m)->m_dat) 399 400 /* 401 * Compute the amount of space available 402 * after the end of data in an mbuf. 403 * 404 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 405 * of checking writability of the mbuf data area rests solely with the caller. 406 */ 407 #define M_TRAILINGSPACE(m) \ 408 ((m)->m_flags & M_EXT ? \ 409 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \ 410 - ((m)->m_data + (m)->m_len) : 0) : \ 411 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 412 413 /* 414 * Arrange to prepend space of size plen to mbuf m. 415 * If a new mbuf must be allocated, how specifies whether to wait. 416 * If how is MB_DONTWAIT and allocation fails, the original mbuf chain 417 * is freed and m is set to NULL. 418 */ 419 #define M_PREPEND(m, plen, how) do { \ 420 struct mbuf **_mmp = &(m); \ 421 struct mbuf *_mm = *_mmp; \ 422 int _mplen = (plen); \ 423 int __mhow = (how); \ 424 \ 425 if (M_LEADINGSPACE(_mm) >= _mplen) { \ 426 _mm->m_data -= _mplen; \ 427 _mm->m_len += _mplen; \ 428 } else \ 429 _mm = m_prepend(_mm, _mplen, __mhow); \ 430 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ 431 _mm->m_pkthdr.len += _mplen; \ 432 *_mmp = _mm; \ 433 } while (0) 434 435 /* Length to m_copy to copy all. */ 436 #define M_COPYALL 1000000000 437 438 /* Compatibility with 4.3 */ 439 #define m_copy(m, o, l) m_copym((m), (o), (l), MB_DONTWAIT) 440 441 #ifdef _KERNEL 442 extern u_int m_clalloc_wid; /* mbuf cluster wait count */ 443 extern u_int m_mballoc_wid; /* mbuf wait count */ 444 extern int max_linkhdr; /* largest link-level header */ 445 extern int max_protohdr; /* largest protocol header */ 446 extern int max_hdr; /* largest link+protocol header */ 447 extern int max_datalen; /* MHLEN - max_hdr */ 448 extern struct mbstat mbstat; 449 extern int mbuf_wait; /* mbuf sleep time */ 450 extern int nmbclusters; 451 extern int nmbufs; 452 453 struct uio; 454 455 void m_adj(struct mbuf *, int); 456 void m_cat(struct mbuf *, struct mbuf *); 457 u_int m_countm(struct mbuf *m, struct mbuf **lastm, u_int *mbcnt); 458 void m_copyback(struct mbuf *, int, int, caddr_t); 459 void m_copydata(const struct mbuf *, int, int, caddr_t); 460 struct mbuf *m_copym(const struct mbuf *, int, int, int); 461 struct mbuf *m_copypacket(struct mbuf *, int); 462 struct mbuf *m_defrag(struct mbuf *, int); 463 struct mbuf *m_defrag_nofree(struct mbuf *, int); 464 struct mbuf *m_devget(char *, int, int, struct ifnet *, 465 void (*copy)(char *, caddr_t, u_int)); 466 struct mbuf *m_dup(struct mbuf *, int); 467 int m_dup_pkthdr(struct mbuf *, const struct mbuf *, int); 468 struct mbuf *m_free(struct mbuf *); 469 void m_freem(struct mbuf *); 470 struct mbuf *m_get(int, int); 471 struct mbuf *m_getcl(int how, short type, int flags); 472 struct mbuf *m_getclr(int, int); 473 struct mbuf *m_gethdr(int, int); 474 struct mbuf *m_getm(struct mbuf *, int, int, int); 475 u_int m_lengthm(struct mbuf *m, struct mbuf **lastm); 476 void m_move_pkthdr(struct mbuf *, struct mbuf *); 477 struct mbuf *m_prepend(struct mbuf *, int, int); 478 void m_print(const struct mbuf *m); 479 struct mbuf *m_pulldown(struct mbuf *, int, int, int *); 480 struct mbuf *m_pullup(struct mbuf *, int); 481 struct mbuf *m_retry(int, int); 482 struct mbuf *m_retryhdr(int, int); 483 struct mbuf *m_split(struct mbuf *, int, int); 484 struct mbuf *m_uiomove(struct uio *, int, int); 485 void m_mclget(struct mbuf *m, int how); 486 int m_sharecount(struct mbuf *m); 487 void m_chtype(struct mbuf *m, int type); 488 489 490 /* 491 * Packets may have annotations attached by affixing a list 492 * of "packet tags" to the pkthdr structure. Packet tags are 493 * dynamically allocated semi-opaque data structures that have 494 * a fixed header (struct m_tag) that specifies the size of the 495 * memory block and a <cookie,type> pair that identifies it. 496 * The cookie is a 32-bit unique unsigned value used to identify 497 * a module or ABI. By convention this value is chose as the 498 * date+time that the module is created, expressed as the number of 499 * seconds since the epoch (e.g. using date -u +'%s'). The type value 500 * is an ABI/module-specific value that identifies a particular annotation 501 * and is private to the module. For compatibility with systems 502 * like openbsd that define packet tags w/o an ABI/module cookie, 503 * the value PACKET_ABI_COMPAT is used to implement m_tag_get and 504 * m_tag_find compatibility shim functions and several tag types are 505 * defined below. Users that do not require compatibility should use 506 * a private cookie value so that packet tag-related definitions 507 * can be maintained privately. 508 * 509 * Note that the packet tag returned by m_tag_allocate has the default 510 * memory alignment implemented by malloc. To reference private data 511 * one can use a construct like: 512 * 513 * struct m_tag *mtag = m_tag_allocate(...); 514 * struct foo *p = (struct foo *)(mtag+1); 515 * 516 * if the alignment of struct m_tag is sufficient for referencing members 517 * of struct foo. Otherwise it is necessary to embed struct m_tag within 518 * the private data structure to insure proper alignment; e.g. 519 * 520 * struct foo { 521 * struct m_tag tag; 522 * ... 523 * }; 524 * struct foo *p = (struct foo *) m_tag_allocate(...); 525 * struct m_tag *mtag = &p->tag; 526 */ 527 528 #define PACKET_TAG_NONE 0 /* Nadda */ 529 530 /* Packet tag for use with PACKET_ABI_COMPAT */ 531 #define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */ 532 /* struct tdb_indent */ 533 #define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */ 534 /* struct tdb_indent */ 535 #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */ 536 /* struct tdb_indent, never added */ 537 #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */ 538 /* struct tdb_indent, never added */ 539 #define PACKET_TAG_IPSEC_PENDING_TDB 5 /* Reminder to do IPsec */ 540 /* struct tdb_indent, never added */ 541 #define PACKET_TAG_ENCAP 6 /* Encap. processing */ 542 /* struct ifnet *, the GIF interface */ 543 #define PACKET_TAG_IPSEC_HISTORY 7 /* IPSEC history */ 544 /* struct ipsec_history */ 545 #define PACKET_TAG_IPV6_INPUT 8 /* IPV6 input processing */ 546 /* struct ip6aux */ 547 #define PACKET_TAG_IPFW_DIVERT 9 /* divert info */ 548 /* uint16_t */ 549 550 /* 551 * As a temporary and low impact solution to replace the even uglier 552 * approach used so far in some parts of the network stack (which relies 553 * on global variables), packet tag-like annotations are stored in MT_TAG 554 * mbufs (or lookalikes) prepended to the actual mbuf chain. 555 * 556 * m_type = MT_TAG 557 * m_flags = m_tag_id 558 * m_next = next buffer in chain. 559 * 560 * BE VERY CAREFUL not to pass these blocks to the mbuf handling routines. 561 */ 562 #define _m_tag_id m_hdr.mh_flags 563 564 /* Packet tags used in the FreeBSD network stack */ 565 #define PACKET_TAG_DUMMYNET 15 /* dummynet info */ 566 /* struct dn_pkt as fake mbuf */ 567 #define PACKET_TAG_IPFORWARD 18 /* ipforward info */ 568 /* struct sockaddr_in * as m_data */ 569 570 /* Packet tag routines */ 571 struct m_tag *m_tag_alloc(u_int32_t, int, int, int); 572 void m_tag_free(struct m_tag *); 573 void m_tag_prepend(struct mbuf *, struct m_tag *); 574 void m_tag_unlink(struct mbuf *, struct m_tag *); 575 void m_tag_delete(struct mbuf *, struct m_tag *); 576 void m_tag_delete_chain(struct mbuf *, struct m_tag *); 577 struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *); 578 struct m_tag *m_tag_copy(struct m_tag *, int); 579 int m_tag_copy_chain(struct mbuf *, const struct mbuf *, int); 580 void m_tag_init(struct mbuf *); 581 struct m_tag *m_tag_first(struct mbuf *); 582 struct m_tag *m_tag_next(struct mbuf *, struct m_tag *); 583 584 /* these are for openbsd compatibility */ 585 #define MTAG_ABI_COMPAT 0 /* compatibility ABI */ 586 587 static __inline struct m_tag * 588 m_tag_get(int type, int length, int wait) 589 { 590 return m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait); 591 } 592 593 static __inline struct m_tag * 594 m_tag_find(struct mbuf *m, int type, struct m_tag *start) 595 { 596 return m_tag_locate(m, MTAG_ABI_COMPAT, type, start); 597 } 598 #endif /* _KERNEL */ 599 600 #endif /* !_SYS_MBUF_H_ */ 601