mbuf.h revision 114851
1/*- 2 * Copyright (c) 1982, 1986, 1988, 1993 3 * The Regents of the University of California. 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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)mbuf.h 8.5 (Berkeley) 2/19/95 34 * $FreeBSD: head/sys/sys/mbuf.h 114851 2003-05-09 02:15:52Z silby $ 35 */ 36 37#ifndef _SYS_MBUF_H_ 38#define _SYS_MBUF_H_ 39 40#include <sys/queue.h> 41 42/* 43 * Mbufs are of a single size, MSIZE (sys/param.h), which 44 * includes overhead. An mbuf may add a single "mbuf cluster" of size 45 * MCLBYTES (also in sys/param.h), which has no additional overhead 46 * and is used instead of the internal data area; this is done when 47 * at least MINCLSIZE of data must be stored. Additionally, it is possible 48 * to allocate a separate buffer externally and attach it to the mbuf in 49 * a way similar to that of mbuf clusters. 50 */ 51#define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */ 52#define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */ 53#define MINCLSIZE (MHLEN + 1) /* smallest amount to put in cluster */ 54#define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */ 55 56#ifdef _KERNEL 57/*- 58 * Macros for type conversion: 59 * mtod(m, t) -- Convert mbuf pointer to data pointer of correct type. 60 * dtom(x) -- Convert data pointer within mbuf to mbuf pointer (XXX). 61 */ 62#define mtod(m, t) ((t)((m)->m_data)) 63#define dtom(x) ((struct mbuf *)((intptr_t)(x) & ~(MSIZE-1))) 64#endif /* _KERNEL */ 65 66/* 67 * Header present at the beginning of every mbuf. 68 */ 69struct m_hdr { 70 struct mbuf *mh_next; /* next buffer in chain */ 71 struct mbuf *mh_nextpkt; /* next chain in queue/record */ 72 caddr_t mh_data; /* location of data */ 73 int mh_len; /* amount of data in this mbuf */ 74 int mh_flags; /* flags; see below */ 75 short mh_type; /* type of data in this mbuf */ 76}; 77 78/* 79 * Packet tag structure (see below for details). 80 */ 81struct m_tag { 82 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */ 83 u_int16_t m_tag_id; /* Tag ID */ 84 u_int16_t m_tag_len; /* Length of data */ 85 u_int32_t m_tag_cookie; /* ABI/Module ID */ 86}; 87 88/* 89 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set. 90 */ 91struct pkthdr { 92 struct ifnet *rcvif; /* rcv interface */ 93 int len; /* total packet length */ 94 /* variables for ip and tcp reassembly */ 95 void *header; /* pointer to packet header */ 96 /* variables for hardware checksum */ 97 int csum_flags; /* flags regarding checksum */ 98 int csum_data; /* data field used by csum routines */ 99 SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */ 100}; 101 102/* 103 * Description of external storage mapped into mbuf; valid only if M_EXT is set. 104 */ 105struct m_ext { 106 caddr_t ext_buf; /* start of buffer */ 107 void (*ext_free) /* free routine if not the usual */ 108 (void *, void *); 109 void *ext_args; /* optional argument pointer */ 110 u_int ext_size; /* size of buffer, for ext_free */ 111 u_int *ref_cnt; /* pointer to ref count info */ 112 int ext_type; /* type of external storage */ 113}; 114 115/* 116 * The core of the mbuf object along with some shortcut defines for 117 * practical purposes. 118 */ 119struct mbuf { 120 struct m_hdr m_hdr; 121 union { 122 struct { 123 struct pkthdr MH_pkthdr; /* M_PKTHDR set */ 124 union { 125 struct m_ext MH_ext; /* M_EXT set */ 126 char MH_databuf[MHLEN]; 127 } MH_dat; 128 } MH; 129 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */ 130 } M_dat; 131}; 132#define m_next m_hdr.mh_next 133#define m_len m_hdr.mh_len 134#define m_data m_hdr.mh_data 135#define m_type m_hdr.mh_type 136#define m_flags m_hdr.mh_flags 137#define m_nextpkt m_hdr.mh_nextpkt 138#define m_act m_nextpkt 139#define m_pkthdr M_dat.MH.MH_pkthdr 140#define m_ext M_dat.MH.MH_dat.MH_ext 141#define m_pktdat M_dat.MH.MH_dat.MH_databuf 142#define m_dat M_dat.M_databuf 143 144/* 145 * mbuf flags. 146 */ 147#define M_EXT 0x0001 /* has associated external storage */ 148#define M_PKTHDR 0x0002 /* start of record */ 149#define M_EOR 0x0004 /* end of record */ 150#define M_RDONLY 0x0008 /* associated data is marked read-only */ 151#define M_PROTO1 0x0010 /* protocol-specific */ 152#define M_PROTO2 0x0020 /* protocol-specific */ 153#define M_PROTO3 0x0040 /* protocol-specific */ 154#define M_PROTO4 0x0080 /* protocol-specific */ 155#define M_PROTO5 0x0100 /* protocol-specific */ 156#define M_FREELIST 0x8000 /* mbuf is on the free list */ 157 158/* 159 * mbuf pkthdr flags (also stored in m_flags). 160 */ 161#define M_BCAST 0x0200 /* send/received as link-level broadcast */ 162#define M_MCAST 0x0400 /* send/received as link-level multicast */ 163#define M_FRAG 0x0800 /* packet is a fragment of a larger packet */ 164#define M_FIRSTFRAG 0x1000 /* packet is first fragment */ 165#define M_LASTFRAG 0x2000 /* packet is last fragment */ 166 167/* 168 * External buffer types: identify ext_buf type. 169 */ 170#define EXT_CLUSTER 1 /* mbuf cluster */ 171#define EXT_SFBUF 2 /* sendfile(2)'s sf_bufs */ 172#define EXT_NET_DRV 100 /* custom ext_buf provided by net driver(s) */ 173#define EXT_MOD_TYPE 200 /* custom module's ext_buf type */ 174#define EXT_DISPOSABLE 300 /* can throw this buffer away w/page flipping */ 175#define EXT_EXTREF 400 /* has externally maintained ref_cnt ptr*/ 176 177/* 178 * Flags copied when copying m_pkthdr. 179 */ 180#define M_COPYFLAGS (M_PKTHDR|M_EOR|M_RDONLY|M_PROTO1|M_PROTO1|M_PROTO2|\ 181 M_PROTO3|M_PROTO4|M_PROTO5|M_BCAST|M_MCAST|\ 182 M_FRAG|M_FIRSTFRAG|M_LASTFRAG) 183 184/* 185 * Flags indicating hw checksum support and sw checksum requirements. 186 */ 187#define CSUM_IP 0x0001 /* will csum IP */ 188#define CSUM_TCP 0x0002 /* will csum TCP */ 189#define CSUM_UDP 0x0004 /* will csum UDP */ 190#define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */ 191#define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */ 192 193#define CSUM_IP_CHECKED 0x0100 /* did csum IP */ 194#define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ 195#define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ 196#define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ 197 198#define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) 199#define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */ 200 201/* 202 * mbuf types. 203 */ 204#define MT_NOTMBUF 0 /* USED INTERNALLY ONLY! Object is not mbuf */ 205#define MT_DATA 1 /* dynamic (data) allocation */ 206#define MT_HEADER 2 /* packet header */ 207#if 0 208#define MT_SOCKET 3 /* socket structure */ 209#define MT_PCB 4 /* protocol control block */ 210#define MT_RTABLE 5 /* routing tables */ 211#define MT_HTABLE 6 /* IMP host tables */ 212#define MT_ATABLE 7 /* address resolution tables */ 213#endif 214#define MT_SONAME 8 /* socket name */ 215#if 0 216#define MT_SOOPTS 10 /* socket options */ 217#endif 218#define MT_FTABLE 11 /* fragment reassembly header */ 219#if 0 220#define MT_RIGHTS 12 /* access rights */ 221#define MT_IFADDR 13 /* interface address */ 222#endif 223#define MT_TAG 13 /* volatile metadata associated to pkts */ 224#define MT_CONTROL 14 /* extra-data protocol message */ 225#define MT_OOBDATA 15 /* expedited data */ 226#define MT_NTYPES 16 /* number of mbuf types for mbtypes[] */ 227 228/* 229 * Mbuf and cluster allocation statistics PCPU structure. 230 */ 231struct mbpstat { 232 u_long mb_mbfree; 233 u_long mb_mbbucks; 234 u_long mb_clfree; 235 u_long mb_clbucks; 236 long mb_mbtypes[MT_NTYPES]; 237 short mb_active; 238}; 239 240/* 241 * General mbuf allocator statistics structure. 242 * XXX: Modifications of these are not protected by any mutex locks nor by 243 * any atomic() manipulations. As a result, we may occasionally lose 244 * a count or two. Luckily, not all of these fields are modified at all 245 * and remain static, and those that are manipulated are only manipulated 246 * in failure situations, which do not occur (hopefully) very often. 247 */ 248struct mbstat { 249 u_long m_drops; /* times failed to allocate */ 250 u_long m_wait; /* times succesfully returned from wait */ 251 u_long m_drain; /* times drained protocols for space */ 252 u_long m_mcfail; /* XXX: times m_copym failed */ 253 u_long m_mpfail; /* XXX: times m_pullup failed */ 254 u_long m_msize; /* length of an mbuf */ 255 u_long m_mclbytes; /* length of an mbuf cluster */ 256 u_long m_minclsize; /* min length of data to allocate a cluster */ 257 u_long m_mlen; /* length of data in an mbuf */ 258 u_long m_mhlen; /* length of data in a header mbuf */ 259 u_int m_mbperbuck; /* number of mbufs per "bucket" */ 260 u_int m_clperbuck; /* number of clusters per "bucket" */ 261 /* Number of mbtypes (gives # elems in mbpstat's mb_mbtypes[] array: */ 262 short m_numtypes; 263}; 264 265/* 266 * Flags specifying how an allocation should be made. 267 * M_DONTWAIT means "don't block if nothing is available" whereas 268 * M_TRYWAIT means "block for mbuf_wait ticks at most if nothing is 269 * available." 270 */ 271#define M_DONTWAIT 0x4 /* don't conflict with M_NOWAIT */ 272#define M_TRYWAIT 0x8 /* or M_WAITOK */ 273#define M_WAIT M_TRYWAIT /* XXX: Deprecated. */ 274#define MBTOM(how) ((how) & M_TRYWAIT ? M_WAITOK : M_NOWAIT) 275 276#ifdef _KERNEL 277/*- 278 * mbuf external reference count management macros. 279 * 280 * MEXT_IS_REF(m): true if (m) is not the only mbuf referencing 281 * the external buffer ext_buf. 282 * 283 * MEXT_REM_REF(m): remove reference to m_ext object. 284 * 285 * MEXT_ADD_REF(m): add reference to m_ext object already 286 * referred to by (m). 287 */ 288#define MEXT_IS_REF(m) (*((m)->m_ext.ref_cnt) > 1) 289 290#define MEXT_REM_REF(m) do { \ 291 KASSERT(*((m)->m_ext.ref_cnt) > 0, ("m_ext refcnt < 0")); \ 292 atomic_subtract_int((m)->m_ext.ref_cnt, 1); \ 293} while(0) 294 295#define MEXT_ADD_REF(m) atomic_add_int((m)->m_ext.ref_cnt, 1) 296 297/* 298 * mbuf, cluster, and external object allocation macros 299 * (for compatibility purposes). 300 */ 301/* NB: M_COPY_PKTHDR is deprecated, use M_MOVE_PKTHDR or m_dup_pktdr */ 302#define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from)) 303#define m_getclr(how, type) m_get_clrd((how), (type)) 304#define MGET(m, how, type) ((m) = m_get((how), (type))) 305#define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type))) 306#define MCLGET(m, how) m_clget((m), (how)) 307#define MEXTADD(m, buf, size, free, args, flags, type) \ 308 m_extadd((m), (caddr_t)(buf), (size), (free), (args), (flags), (type)) 309 310/* 311 * MEXTFREE(m): disassociate (and possibly free) an external object from (m). 312 * 313 * If the atomic_cmpset_int() returns 0, then we effectively do nothing 314 * in terms of "cleaning up" (freeing the ext buf and ref. counter) as 315 * this means that either there are still references, or another thread 316 * is taking care of the clean-up. 317 */ 318#define MEXTFREE(m) do { \ 319 struct mbuf *_mb = (m); \ 320 \ 321 MEXT_REM_REF(_mb); \ 322 if (atomic_cmpset_int(_mb->m_ext.ref_cnt, 0, 1)) \ 323 _mext_free(_mb); \ 324 _mb->m_flags &= ~M_EXT; \ 325} while (0) 326 327/* 328 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this 329 * can be both the local data payload, or an external buffer area, 330 * depending on whether M_EXT is set). 331 */ 332#define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && (!((m)->m_flags \ 333 & M_EXT) || !MEXT_IS_REF(m))) 334 335/* 336 * Check if the supplied mbuf has a packet header, or else panic. 337 */ 338#define M_ASSERTPKTHDR(m) \ 339 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \ 340 ("%s: no mbuf packet header!", __func__)) 341 342/* 343 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place 344 * an object of the specified size at the end of the mbuf, longword aligned. 345 */ 346#define M_ALIGN(m, len) do { \ 347 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ 348} while (0) 349 350/* 351 * As above, for mbufs allocated with m_gethdr/MGETHDR 352 * or initialized by M_COPY_PKTHDR. 353 */ 354#define MH_ALIGN(m, len) do { \ 355 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ 356} while (0) 357 358/* 359 * Compute the amount of space available 360 * before the current start of data in an mbuf. 361 * 362 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 363 * of checking writability of the mbuf data area rests solely with the caller. 364 */ 365#define M_LEADINGSPACE(m) \ 366 ((m)->m_flags & M_EXT ? \ 367 (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \ 368 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ 369 (m)->m_data - (m)->m_dat) 370 371/* 372 * Compute the amount of space available 373 * after the end of data in an mbuf. 374 * 375 * The M_WRITABLE() is a temporary, conservative safety measure: the burden 376 * of checking writability of the mbuf data area rests solely with the caller. 377 */ 378#define M_TRAILINGSPACE(m) \ 379 ((m)->m_flags & M_EXT ? \ 380 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \ 381 - ((m)->m_data + (m)->m_len) : 0) : \ 382 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) 383 384/* 385 * Arrange to prepend space of size plen to mbuf m. 386 * If a new mbuf must be allocated, how specifies whether to wait. 387 * If the allocation fails, the original mbuf chain is freed and m is 388 * set to NULL. 389 */ 390#define M_PREPEND(m, plen, how) do { \ 391 struct mbuf **_mmp = &(m); \ 392 struct mbuf *_mm = *_mmp; \ 393 int _mplen = (plen); \ 394 int __mhow = (how); \ 395 \ 396 if (M_LEADINGSPACE(_mm) >= _mplen) { \ 397 _mm->m_data -= _mplen; \ 398 _mm->m_len += _mplen; \ 399 } else \ 400 _mm = m_prepend(_mm, _mplen, __mhow); \ 401 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ 402 _mm->m_pkthdr.len += _mplen; \ 403 *_mmp = _mm; \ 404} while (0) 405 406/* 407 * Change mbuf to new type. 408 * This is a relatively expensive operation and should be avoided. 409 */ 410#define MCHTYPE(m, t) m_chtype((m), (t)) 411 412/* Length to m_copy to copy all. */ 413#define M_COPYALL 1000000000 414 415/* Compatibility with 4.3. */ 416#define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT) 417 418extern int max_datalen; /* MHLEN - max_hdr */ 419extern int max_hdr; /* Largest link + protocol header */ 420extern int max_linkhdr; /* Largest link-level header */ 421extern int max_protohdr; /* Largest protocol header */ 422extern struct mbstat mbstat; /* General mbuf stats/infos */ 423extern int nmbclusters; /* Maximum number of clusters */ 424extern int nmbcnt; /* Scale kmem_map for counter space */ 425extern int nmbufs; /* Maximum number of mbufs */ 426extern int nsfbufs; /* Number of sendfile(2) bufs */ 427 428void _mext_free(struct mbuf *); 429void m_adj(struct mbuf *, int); 430void m_cat(struct mbuf *, struct mbuf *); 431void m_chtype(struct mbuf *, short); 432void m_clget(struct mbuf *, int); 433void m_extadd(struct mbuf *, caddr_t, u_int, 434 void (*)(void *, void *), void *, int, int); 435void m_copyback(struct mbuf *, int, int, caddr_t); 436void m_copydata(const struct mbuf *, int, int, caddr_t); 437struct mbuf *m_copym(struct mbuf *, int, int, int); 438struct mbuf *m_copypacket(struct mbuf *, int); 439void m_copy_pkthdr(struct mbuf *, struct mbuf *); 440struct mbuf *m_defrag(struct mbuf *, int); 441struct mbuf *m_devget(char *, int, int, struct ifnet *, 442 void (*)(char *, caddr_t, u_int)); 443struct mbuf *m_dup(struct mbuf *, int); 444int m_dup_pkthdr(struct mbuf *, struct mbuf *, int); 445u_int m_fixhdr(struct mbuf *); 446struct mbuf *m_free(struct mbuf *); 447void m_freem(struct mbuf *); 448struct mbuf *m_get(int, short); 449struct mbuf *m_get_clrd(int, short); 450struct mbuf *m_getcl(int, short, int); 451struct mbuf *m_gethdr(int, short); 452struct mbuf *m_gethdr_clrd(int, short); 453struct mbuf *m_getm(struct mbuf *, int, int, short); 454u_int m_length(struct mbuf *, struct mbuf **); 455void m_move_pkthdr(struct mbuf *, struct mbuf *); 456struct mbuf *m_prepend(struct mbuf *, int, int); 457void m_print(const struct mbuf *); 458struct mbuf *m_pulldown(struct mbuf *, int, int, int *); 459struct mbuf *m_pullup(struct mbuf *, int); 460struct mbuf *m_split(struct mbuf *, int, int); 461 462/* 463 * Packets may have annotations attached by affixing a list 464 * of "packet tags" to the pkthdr structure. Packet tags are 465 * dynamically allocated semi-opaque data structures that have 466 * a fixed header (struct m_tag) that specifies the size of the 467 * memory block and a <cookie,type> pair that identifies it. 468 * The cookie is a 32-bit unique unsigned value used to identify 469 * a module or ABI. By convention this value is chose as the 470 * date+time that the module is created, expressed as the number of 471 * seconds since the epoch (e.g. using date -u +'%s'). The type value 472 * is an ABI/module-specific value that identifies a particular annotation 473 * and is private to the module. For compatibility with systems 474 * like openbsd that define packet tags w/o an ABI/module cookie, 475 * the value PACKET_ABI_COMPAT is used to implement m_tag_get and 476 * m_tag_find compatibility shim functions and several tag types are 477 * defined below. Users that do not require compatibility should use 478 * a private cookie value so that packet tag-related definitions 479 * can be maintained privately. 480 * 481 * Note that the packet tag returned by m_tag_allocate has the default 482 * memory alignment implemented by malloc. To reference private data 483 * one can use a construct like: 484 * 485 * struct m_tag *mtag = m_tag_allocate(...); 486 * struct foo *p = (struct foo *)(mtag+1); 487 * 488 * if the alignment of struct m_tag is sufficient for referencing members 489 * of struct foo. Otherwise it is necessary to embed struct m_tag within 490 * the private data structure to insure proper alignment; e.g. 491 * 492 * struct foo { 493 * struct m_tag tag; 494 * ... 495 * }; 496 * struct foo *p = (struct foo *) m_tag_allocate(...); 497 * struct m_tag *mtag = &p->tag; 498 */ 499 500#define PACKET_TAG_NONE 0 /* Nadda */ 501 502/* Packet tag for use with PACKET_ABI_COMPAT */ 503#define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */ 504#define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */ 505#define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */ 506#define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */ 507#define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO 5 /* NIC notifies IPsec */ 508#define PACKET_TAG_IPSEC_PENDING_TDB 6 /* Reminder to do IPsec */ 509#define PACKET_TAG_BRIDGE 7 /* Bridge processing done */ 510#define PACKET_TAG_GIF 8 /* GIF processing done */ 511#define PACKET_TAG_GRE 9 /* GRE processing done */ 512#define PACKET_TAG_IN_PACKET_CHECKSUM 10 /* NIC checksumming done */ 513#define PACKET_TAG_ENCAP 11 /* Encap. processing */ 514#define PACKET_TAG_IPSEC_SOCKET 12 /* IPSEC socket ref */ 515#define PACKET_TAG_IPSEC_HISTORY 13 /* IPSEC history */ 516#define PACKET_TAG_IPV6_INPUT 14 /* IPV6 input processing */ 517 518/* 519 * As a temporary and low impact solution to replace the even uglier 520 * approach used so far in some parts of the network stack (which relies 521 * on global variables), packet tag-like annotations are stored in MT_TAG 522 * mbufs (or lookalikes) prepended to the actual mbuf chain. 523 * 524 * m_type = MT_TAG 525 * m_flags = m_tag_id 526 * m_next = next buffer in chain. 527 * 528 * BE VERY CAREFUL not to pass these blocks to the mbuf handling routines. 529 */ 530#define _m_tag_id m_hdr.mh_flags 531 532/* Packet tags used in the FreeBSD network stack */ 533#define PACKET_TAG_DUMMYNET 15 /* dummynet info */ 534#define PACKET_TAG_IPFW 16 /* ipfw classification */ 535#define PACKET_TAG_DIVERT 17 /* divert info */ 536#define PACKET_TAG_IPFORWARD 18 /* ipforward info */ 537#define PACKET_TAG_MACLABEL 19 /* MAC label */ 538 539/* Packet tag routines */ 540struct m_tag *m_tag_alloc(u_int32_t, int, int, int); 541void m_tag_free(struct m_tag *); 542void m_tag_prepend(struct mbuf *, struct m_tag *); 543void m_tag_unlink(struct mbuf *, struct m_tag *); 544void m_tag_delete(struct mbuf *, struct m_tag *); 545void m_tag_delete_chain(struct mbuf *, struct m_tag *); 546struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *); 547struct m_tag *m_tag_copy(struct m_tag *, int); 548int m_tag_copy_chain(struct mbuf *, struct mbuf *, int); 549void m_tag_init(struct mbuf *); 550struct m_tag *m_tag_first(struct mbuf *); 551struct m_tag *m_tag_next(struct mbuf *, struct m_tag *); 552 553/* these are for openbsd compatibility */ 554#define MTAG_ABI_COMPAT 0 /* compatibility ABI */ 555 556static __inline struct m_tag * 557m_tag_get(int type, int length, int wait) 558{ 559 return m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait); 560} 561 562static __inline struct m_tag * 563m_tag_find(struct mbuf *m, int type, struct m_tag *start) 564{ 565 return m_tag_locate(m, MTAG_ABI_COMPAT, type, start); 566} 567#endif /* _KERNEL */ 568 569#endif /* !_SYS_MBUF_H_ */ 570