freebsd-dev/sys/netinet/ip6.h
Robert Watson 6c572040c6 Eliminate use of M_EXT in IP6_EXTHDR_CHECK() by trimming a redundant
'if'/'else' case: it matches the simple 'else' case that follows.

This reduces awareness of external-storage mechanics outside of the
mbuf allocator.

Reviewed by:	bz
MFC after:	3 days
Sponsored by:	EMC / Isilon Storage Division
Differential Revision:	https://reviews.freebsd.org/D900
2014-10-05 06:28:53 +00:00

347 lines
12 KiB
C

/* $FreeBSD$ */
/* $KAME: ip6.h,v 1.18 2001/03/29 05:34:30 itojun Exp $ */
/*-
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*-
* Copyright (c) 1982, 1986, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ip.h 8.1 (Berkeley) 6/10/93
*/
#ifndef _NETINET_IP6_H_
#define _NETINET_IP6_H_
/*
* Definition for internet protocol version 6.
* RFC 2460
*/
struct ip6_hdr {
union {
struct ip6_hdrctl {
u_int32_t ip6_un1_flow; /* 20 bits of flow-ID */
u_int16_t ip6_un1_plen; /* payload length */
u_int8_t ip6_un1_nxt; /* next header */
u_int8_t ip6_un1_hlim; /* hop limit */
} ip6_un1;
u_int8_t ip6_un2_vfc; /* 4 bits version, top 4 bits class */
} ip6_ctlun;
struct in6_addr ip6_src; /* source address */
struct in6_addr ip6_dst; /* destination address */
} __packed;
#define ip6_vfc ip6_ctlun.ip6_un2_vfc
#define ip6_flow ip6_ctlun.ip6_un1.ip6_un1_flow
#define ip6_plen ip6_ctlun.ip6_un1.ip6_un1_plen
#define ip6_nxt ip6_ctlun.ip6_un1.ip6_un1_nxt
#define ip6_hlim ip6_ctlun.ip6_un1.ip6_un1_hlim
#define ip6_hops ip6_ctlun.ip6_un1.ip6_un1_hlim
#define IPV6_VERSION 0x60
#define IPV6_VERSION_MASK 0xf0
#if BYTE_ORDER == BIG_ENDIAN
#define IPV6_FLOWINFO_MASK 0x0fffffff /* flow info (28 bits) */
#define IPV6_FLOWLABEL_MASK 0x000fffff /* flow label (20 bits) */
#else
#if BYTE_ORDER == LITTLE_ENDIAN
#define IPV6_FLOWINFO_MASK 0xffffff0f /* flow info (28 bits) */
#define IPV6_FLOWLABEL_MASK 0xffff0f00 /* flow label (20 bits) */
#endif /* LITTLE_ENDIAN */
#endif
#if 1
/* ECN bits proposed by Sally Floyd */
#define IP6TOS_CE 0x01 /* congestion experienced */
#define IP6TOS_ECT 0x02 /* ECN-capable transport */
#endif
/*
* Extension Headers
*/
struct ip6_ext {
u_int8_t ip6e_nxt;
u_int8_t ip6e_len;
} __packed;
/* Hop-by-Hop options header */
/* XXX should we pad it to force alignment on an 8-byte boundary? */
struct ip6_hbh {
u_int8_t ip6h_nxt; /* next header */
u_int8_t ip6h_len; /* length in units of 8 octets */
/* followed by options */
} __packed;
/* Destination options header */
/* XXX should we pad it to force alignment on an 8-byte boundary? */
struct ip6_dest {
u_int8_t ip6d_nxt; /* next header */
u_int8_t ip6d_len; /* length in units of 8 octets */
/* followed by options */
} __packed;
/* Option types and related macros */
#define IP6OPT_PAD1 0x00 /* 00 0 00000 */
#define IP6OPT_PADN 0x01 /* 00 0 00001 */
#define IP6OPT_JUMBO 0xC2 /* 11 0 00010 = 194 */
#define IP6OPT_NSAP_ADDR 0xC3 /* 11 0 00011 */
#define IP6OPT_TUNNEL_LIMIT 0x04 /* 00 0 00100 */
#ifndef _KERNEL
#define IP6OPT_RTALERT 0x05 /* 00 0 00101 (KAME definition) */
#endif
#define IP6OPT_ROUTER_ALERT 0x05 /* 00 0 00101 (RFC3542, recommended) */
#define IP6OPT_RTALERT_LEN 4
#define IP6OPT_RTALERT_MLD 0 /* Datagram contains an MLD message */
#define IP6OPT_RTALERT_RSVP 1 /* Datagram contains an RSVP message */
#define IP6OPT_RTALERT_ACTNET 2 /* contains an Active Networks msg */
#define IP6OPT_MINLEN 2
#define IP6OPT_EID 0x8a /* 10 0 01010 */
#define IP6OPT_TYPE(o) ((o) & 0xC0)
#define IP6OPT_TYPE_SKIP 0x00
#define IP6OPT_TYPE_DISCARD 0x40
#define IP6OPT_TYPE_FORCEICMP 0x80
#define IP6OPT_TYPE_ICMP 0xC0
#define IP6OPT_MUTABLE 0x20
/* IPv6 options: common part */
struct ip6_opt {
u_int8_t ip6o_type;
u_int8_t ip6o_len;
} __packed;
/* Jumbo Payload Option */
struct ip6_opt_jumbo {
u_int8_t ip6oj_type;
u_int8_t ip6oj_len;
u_int8_t ip6oj_jumbo_len[4];
} __packed;
#define IP6OPT_JUMBO_LEN 6
/* NSAP Address Option */
struct ip6_opt_nsap {
u_int8_t ip6on_type;
u_int8_t ip6on_len;
u_int8_t ip6on_src_nsap_len;
u_int8_t ip6on_dst_nsap_len;
/* followed by source NSAP */
/* followed by destination NSAP */
} __packed;
/* Tunnel Limit Option */
struct ip6_opt_tunnel {
u_int8_t ip6ot_type;
u_int8_t ip6ot_len;
u_int8_t ip6ot_encap_limit;
} __packed;
/* Router Alert Option */
struct ip6_opt_router {
u_int8_t ip6or_type;
u_int8_t ip6or_len;
u_int8_t ip6or_value[2];
} __packed;
/* Router alert values (in network byte order) */
#if BYTE_ORDER == BIG_ENDIAN
#define IP6_ALERT_MLD 0x0000
#define IP6_ALERT_RSVP 0x0001
#define IP6_ALERT_AN 0x0002
#else
#if BYTE_ORDER == LITTLE_ENDIAN
#define IP6_ALERT_MLD 0x0000
#define IP6_ALERT_RSVP 0x0100
#define IP6_ALERT_AN 0x0200
#endif /* LITTLE_ENDIAN */
#endif
/* Routing header */
struct ip6_rthdr {
u_int8_t ip6r_nxt; /* next header */
u_int8_t ip6r_len; /* length in units of 8 octets */
u_int8_t ip6r_type; /* routing type */
u_int8_t ip6r_segleft; /* segments left */
/* followed by routing type specific data */
} __packed;
/* Type 0 Routing header, deprecated by RFC 5095. */
struct ip6_rthdr0 {
u_int8_t ip6r0_nxt; /* next header */
u_int8_t ip6r0_len; /* length in units of 8 octets */
u_int8_t ip6r0_type; /* always zero */
u_int8_t ip6r0_segleft; /* segments left */
u_int32_t ip6r0_reserved; /* reserved field */
/* followed by up to 127 struct in6_addr */
} __packed;
/* Fragment header */
struct ip6_frag {
u_int8_t ip6f_nxt; /* next header */
u_int8_t ip6f_reserved; /* reserved field */
u_int16_t ip6f_offlg; /* offset, reserved, and flag */
u_int32_t ip6f_ident; /* identification */
} __packed;
#if BYTE_ORDER == BIG_ENDIAN
#define IP6F_OFF_MASK 0xfff8 /* mask out offset from _offlg */
#define IP6F_RESERVED_MASK 0x0006 /* reserved bits in ip6f_offlg */
#define IP6F_MORE_FRAG 0x0001 /* more-fragments flag */
#else /* BYTE_ORDER == LITTLE_ENDIAN */
#define IP6F_OFF_MASK 0xf8ff /* mask out offset from _offlg */
#define IP6F_RESERVED_MASK 0x0600 /* reserved bits in ip6f_offlg */
#define IP6F_MORE_FRAG 0x0100 /* more-fragments flag */
#endif /* BYTE_ORDER == LITTLE_ENDIAN */
/*
* Internet implementation parameters.
*/
#define IPV6_MAXHLIM 255 /* maximum hoplimit */
#define IPV6_DEFHLIM 64 /* default hlim */
#define IPV6_FRAGTTL 120 /* ttl for fragment packets, in slowtimo tick */
#define IPV6_HLIMDEC 1 /* subtracted when forwarding */
#define IPV6_MMTU 1280 /* minimal MTU and reassembly. 1024 + 256 */
#define IPV6_MAXPACKET 65535 /* ip6 max packet size without Jumbo payload*/
#define IPV6_MAXOPTHDR 2048 /* max option header size, 256 64-bit words */
#ifdef _KERNEL
/*
* IP6_EXTHDR_CHECK ensures that region between the IP6 header and the
* target header (including IPv6 itself, extension headers and
* TCP/UDP/ICMP6 headers) are contiguous. KAME requires drivers
* to store incoming data into one internal mbuf or one or more external
* mbufs(never into two or more internal mbufs). Thus, the third case is
* supposed to never be matched but is prepared just in case.
*/
#define IP6_EXTHDR_CHECK(m, off, hlen, ret) \
do { \
if ((m)->m_next != NULL) { \
if (((m)->m_flags & M_LOOP) && \
((m)->m_len < (off) + (hlen)) && \
(((m) = m_pullup((m), (off) + (hlen))) == NULL)) { \
IP6STAT_INC(ip6s_exthdrtoolong); \
return ret; \
} else { \
if ((m)->m_len < (off) + (hlen)) { \
IP6STAT_INC(ip6s_exthdrtoolong); \
m_freem(m); \
return ret; \
} \
} \
} else { \
if ((m)->m_len < (off) + (hlen)) { \
IP6STAT_INC(ip6s_tooshort); \
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated); \
m_freem(m); \
return ret; \
} \
} \
} while (/*CONSTCOND*/ 0)
/*
* IP6_EXTHDR_GET ensures that intermediate protocol header (from "off" to
* "len") is located in single mbuf, on contiguous memory region.
* The pointer to the region will be returned to pointer variable "val",
* with type "typ".
* IP6_EXTHDR_GET0 does the same, except that it aligns the structure at the
* very top of mbuf. GET0 is likely to make memory copy than GET.
*
* XXX we're now testing this, needs m_pulldown()
*/
#define IP6_EXTHDR_GET(val, typ, m, off, len) \
do { \
struct mbuf *t; \
int tmp; \
if ((m)->m_len >= (off) + (len)) \
(val) = (typ)(mtod((m), caddr_t) + (off)); \
else { \
t = m_pulldown((m), (off), (len), &tmp); \
if (t) { \
if (t->m_len < tmp + (len)) \
panic("m_pulldown malfunction"); \
(val) = (typ)(mtod(t, caddr_t) + tmp); \
} else { \
(val) = (typ)NULL; \
(m) = NULL; \
} \
} \
} while (/*CONSTCOND*/ 0)
#define IP6_EXTHDR_GET0(val, typ, m, off, len) \
do { \
struct mbuf *t; \
if ((off) == 0) \
(val) = (typ)mtod(m, caddr_t); \
else { \
t = m_pulldown((m), (off), (len), NULL); \
if (t) { \
if (t->m_len < (len)) \
panic("m_pulldown malfunction"); \
(val) = (typ)mtod(t, caddr_t); \
} else { \
(val) = (typ)NULL; \
(m) = NULL; \
} \
} \
} while (/*CONSTCOND*/ 0)
#endif /*_KERNEL*/
#endif /* not _NETINET_IP6_H_ */