ipv6.h

linux 内核源代码

/*
 *	Linux INET6 implementation
 *
 *	Authors:
 *	Pedro Roque		<[e-mail]>
 *
 *	$Id: ipv6.h,v 1.1 2002/05/20 15:13:07 jgrimm Exp $
 *
 *	This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#ifndef _NET_IPV6_H
#define _NET_IPV6_H

#include <linux/ipv6.h>
#include <linux/hardirq.h>
#include <net/if_inet6.h>
#include <net/ndisc.h>
#include <net/flow.h>
#include <net/snmp.h>

#define SIN6_LEN_RFC2133	24

#define IPV6_MAXPLEN		65535

/*
 *	NextHeader field of IPv6 header
 */

#define NEXTHDR_HOP		0	/* Hop-by-hop option header. */
#define NEXTHDR_TCP		6	/* TCP segment. */
#define NEXTHDR_UDP		17	/* UDP message. */
#define NEXTHDR_IPV6		41	/* IPv6 in IPv6 */
#define NEXTHDR_ROUTING		43	/* Routing header. */
#define NEXTHDR_FRAGMENT	44	/* Fragmentation/reassembly header. */
#define NEXTHDR_ESP		50	/* Encapsulating security payload. */
#define NEXTHDR_AUTH		51	/* Authentication header. */
#define NEXTHDR_ICMP		58	/* ICMP for IPv6. */
#define NEXTHDR_NONE		59	/* No next header */
#define NEXTHDR_DEST		60	/* Destination options header. */
#define NEXTHDR_MOBILITY	135	/* Mobility header. */

#define NEXTHDR_MAX		255



#define IPV6_DEFAULT_HOPLIMIT   64
#define IPV6_DEFAULT_MCASTHOPS	1

/*
 *	Addr type
 *	
 *	type	-	unicast | multicast
 *	scope	-	local	| site	    | global
 *	v4	-	compat
 *	v4mapped
 *	any
 *	loopback
 */

#define IPV6_ADDR_ANY		0x0000U

#define IPV6_ADDR_UNICAST      	0x0001U	
#define IPV6_ADDR_MULTICAST    	0x0002U	

#define IPV6_ADDR_LOOPBACK	0x0010U
#define IPV6_ADDR_LINKLOCAL	0x0020U
#define IPV6_ADDR_SITELOCAL	0x0040U

#define IPV6_ADDR_COMPATv4	0x0080U

#define IPV6_ADDR_SCOPE_MASK	0x00f0U

#define IPV6_ADDR_MAPPED	0x1000U
#define IPV6_ADDR_RESERVED	0x2000U	/* reserved address space */

/*
 *	Addr scopes
 */
#ifdef __KERNEL__
#define IPV6_ADDR_MC_SCOPE(a)	\
	((a)->s6_addr[1] & 0x0f)	/* nonstandard */
#define __IPV6_ADDR_SCOPE_INVALID	-1
#endif
#define IPV6_ADDR_SCOPE_NODELOCAL	0x01
#define IPV6_ADDR_SCOPE_LINKLOCAL	0x02
#define IPV6_ADDR_SCOPE_SITELOCAL	0x05
#define IPV6_ADDR_SCOPE_ORGLOCAL	0x08
#define IPV6_ADDR_SCOPE_GLOBAL		0x0e

/*
 *	fragmentation header
 */

struct frag_hdr {
	__u8	nexthdr;
	__u8	reserved;
	__be16	frag_off;
	__be32	identification;
};

#define	IP6_MF	0x0001

#ifdef __KERNEL__

#include <net/sock.h>

/* sysctls */
extern int sysctl_ipv6_bindv6only;
extern int sysctl_mld_max_msf;

#define _DEVINC(statname, modifier, idev, field)			\
({									\
	struct inet6_dev *_idev = (idev);				\
	if (likely(_idev != NULL))					\
		SNMP_INC_STATS##modifier((_idev)->stats.statname, (field)); \
	SNMP_INC_STATS##modifier(statname##_statistics, (field));	\
})

#define _DEVADD(statname, modifier, idev, field, val)			\
({									\
	struct inet6_dev *_idev = (idev);				\
	if (likely(_idev != NULL))					\
		SNMP_ADD_STATS##modifier((_idev)->stats.statname, (field), (val)); \
	SNMP_ADD_STATS##modifier(statname##_statistics, (field), (val));\
})

/* MIBs */
DECLARE_SNMP_STAT(struct ipstats_mib, ipv6_statistics);

#define IP6_INC_STATS(idev,field)	_DEVINC(ipv6, , idev, field)
#define IP6_INC_STATS_BH(idev,field)	_DEVINC(ipv6, _BH, idev, field)
#define IP6_INC_STATS_USER(idev,field)	_DEVINC(ipv6, _USER, idev, field)
#define IP6_ADD_STATS_BH(idev,field,val) _DEVADD(ipv6, _BH, idev, field, val)

DECLARE_SNMP_STAT(struct icmpv6_mib, icmpv6_statistics);
DECLARE_SNMP_STAT(struct icmpv6msg_mib, icmpv6msg_statistics);

#define ICMP6_INC_STATS(idev, field)	_DEVINC(icmpv6, , idev, field)
#define ICMP6_INC_STATS_BH(idev, field)	_DEVINC(icmpv6, _BH, idev, field)
#define ICMP6_INC_STATS_USER(idev, field) _DEVINC(icmpv6, _USER, idev, field)

#define ICMP6_INC_STATS_OFFSET_BH(idev, field, offset)	({			\
	struct inet6_dev *_idev = idev;						\
	__typeof__(offset) _offset = (offset);					\
	if (likely(_idev != NULL))						\
		SNMP_INC_STATS_OFFSET_BH(_idev->stats.icmpv6, field, _offset);	\
	SNMP_INC_STATS_OFFSET_BH(icmpv6_statistics, field, _offset);    	\
})

#define ICMP6MSGOUT_INC_STATS(idev, field) \
	_DEVINC(icmpv6msg, , idev, field +256)
#define ICMP6MSGOUT_INC_STATS_BH(idev, field) \
	_DEVINC(icmpv6msg, _BH, idev, field +256)
#define ICMP6MSGOUT_INC_STATS_USER(idev, field) \
	_DEVINC(icmpv6msg, _USER, idev, field +256)
#define ICMP6MSGIN_INC_STATS(idev, field) \
	 _DEVINC(icmpv6msg, , idev, field)
#define ICMP6MSGIN_INC_STATS_BH(idev, field) \
	_DEVINC(icmpv6msg, _BH, idev, field)
#define ICMP6MSGIN_INC_STATS_USER(idev, field) \
	_DEVINC(icmpv6msg, _USER, idev, field)

DECLARE_SNMP_STAT(struct udp_mib, udp_stats_in6);
DECLARE_SNMP_STAT(struct udp_mib, udplite_stats_in6);
#define UDP6_INC_STATS_BH(field, is_udplite) 			      do  {  \
	if (is_udplite) SNMP_INC_STATS_BH(udplite_stats_in6, field);         \
	else		SNMP_INC_STATS_BH(udp_stats_in6, field);    } while(0)
#define UDP6_INC_STATS_USER(field, is_udplite)			       do {    \
	if (is_udplite) SNMP_INC_STATS_USER(udplite_stats_in6, field);         \
	else		SNMP_INC_STATS_USER(udp_stats_in6, field);    } while(0)

struct ip6_ra_chain
{
	struct ip6_ra_chain	*next;
	struct sock		*sk;
	int			sel;
	void			(*destructor)(struct sock *);
};

extern struct ip6_ra_chain	*ip6_ra_chain;
extern rwlock_t ip6_ra_lock;

/*
   This structure is prepared by protocol, when parsing
   ancillary data and passed to IPv6.
 */

struct ipv6_txoptions
{
	/* Length of this structure */
	int			tot_len;

	/* length of extension headers   */

	__u16			opt_flen;	/* after fragment hdr */
	__u16			opt_nflen;	/* before fragment hdr */

	struct ipv6_opt_hdr	*hopopt;
	struct ipv6_opt_hdr	*dst0opt;
	struct ipv6_rt_hdr	*srcrt;	/* Routing Header */
	struct ipv6_opt_hdr	*dst1opt;

	/* Option buffer, as read by IPV6_PKTOPTIONS, starts here. */
};

struct ip6_flowlabel
{
	struct ip6_flowlabel	*next;
	__be32			label;
	atomic_t		users;
	struct in6_addr		dst;
	struct ipv6_txoptions	*opt;
	unsigned long		linger;
	u8			share;
	u32			owner;
	unsigned long		lastuse;
	unsigned long		expires;
};

#define IPV6_FLOWINFO_MASK	__constant_htonl(0x0FFFFFFF)
#define IPV6_FLOWLABEL_MASK	__constant_htonl(0x000FFFFF)

struct ipv6_fl_socklist
{
	struct ipv6_fl_socklist	*next;
	struct ip6_flowlabel	*fl;
};

extern struct ip6_flowlabel	*fl6_sock_lookup(struct sock *sk, __be32 label);
extern struct ipv6_txoptions	*fl6_merge_options(struct ipv6_txoptions * opt_space,
						   struct ip6_flowlabel * fl,
						   struct ipv6_txoptions * fopt);
extern void			fl6_free_socklist(struct sock *sk);
extern int			ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen);
extern void			ip6_flowlabel_init(void);
extern void			ip6_flowlabel_cleanup(void);

static inline void fl6_sock_release(struct ip6_flowlabel *fl)
{
	if (fl)
		atomic_dec(&fl->users);
}

extern int 			ip6_ra_control(struct sock *sk, int sel,
					       void (*destructor)(struct sock *));


extern int			ipv6_parse_hopopts(struct sk_buff *skb);

extern struct ipv6_txoptions *  ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt);
extern struct ipv6_txoptions *	ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
						   int newtype,
						   struct ipv6_opt_hdr __user *newopt,
						   int newoptlen);
struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
					  struct ipv6_txoptions *opt);

extern int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb);

int ip6_frag_nqueues(void);
int ip6_frag_mem(void);

#define IPV6_FRAG_TIMEOUT	(60*HZ)		/* 60 seconds */

/*
 *	Function prototype for build_xmit
 */

typedef int		(*inet_getfrag_t) (const void *data,
					   struct in6_addr *addr,
					   char *,
					   unsigned int, unsigned int);

extern int __ipv6_addr_type(const struct in6_addr *addr);
static inline int ipv6_addr_type(const struct in6_addr *addr)
{
	return __ipv6_addr_type(addr) & 0xffff;
}

static inline int ipv6_addr_scope(const struct in6_addr *addr)
{
	return __ipv6_addr_type(addr) & IPV6_ADDR_SCOPE_MASK;
}

static inline int __ipv6_addr_src_scope(int type)
{
	return (type == IPV6_ADDR_ANY ? __IPV6_ADDR_SCOPE_INVALID : (type >> 16));
}

static inline int ipv6_addr_src_scope(const struct in6_addr *addr)
{
	return __ipv6_addr_src_scope(__ipv6_addr_type(addr));
}

static inline int ipv6_addr_cmp(const struct in6_addr *a1, const struct in6_addr *a2)
{
	return memcmp(a1, a2, sizeof(struct in6_addr));
}

static inline int
ipv6_masked_addr_cmp(const struct in6_addr *a1, const struct in6_addr *m,
		     const struct in6_addr *a2)
{
	unsigned int i;

	for (i = 0; i < 4; i++)
		if ((a1->s6_addr32[i] ^ a2->s6_addr32[i]) & m->s6_addr32[i])
			return 1;
	return 0;
}

static inline void ipv6_addr_copy(struct in6_addr *a1, const struct in6_addr *a2)
{
	memcpy(a1, a2, sizeof(struct in6_addr));
}

static inline void ipv6_addr_prefix(struct in6_addr *pfx, 
				    const struct in6_addr *addr,