af_inet6.c

linux 内核源代码

	.connect	   = inet_stream_connect,	/* ok		*/
	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
	.accept		   = inet_accept,		/* ok		*/
	.getname	   = inet6_getname,
	.poll		   = tcp_poll,			/* ok		*/
	.ioctl		   = inet6_ioctl,		/* must change  */
	.listen		   = inet_listen,		/* ok		*/
	.shutdown	   = inet_shutdown,		/* ok		*/
	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
	.sendmsg	   = tcp_sendmsg,		/* ok		*/
	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
	.mmap		   = sock_no_mmap,
	.sendpage	   = tcp_sendpage,
#ifdef CONFIG_COMPAT
	.compat_setsockopt = compat_sock_common_setsockopt,
	.compat_getsockopt = compat_sock_common_getsockopt,
#endif
};

const struct proto_ops inet6_dgram_ops = {
	.family		   = PF_INET6,
	.owner		   = THIS_MODULE,
	.release	   = inet6_release,
	.bind		   = inet6_bind,
	.connect	   = inet_dgram_connect,	/* ok		*/
	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
	.accept		   = sock_no_accept,		/* a do nothing	*/
	.getname	   = inet6_getname,
	.poll		   = udp_poll,			/* ok		*/
	.ioctl		   = inet6_ioctl,		/* must change  */
	.listen		   = sock_no_listen,		/* ok		*/
	.shutdown	   = inet_shutdown,		/* ok		*/
	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
	.sendmsg	   = inet_sendmsg,		/* ok		*/
	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
	.mmap		   = sock_no_mmap,
	.sendpage	   = sock_no_sendpage,
#ifdef CONFIG_COMPAT
	.compat_setsockopt = compat_sock_common_setsockopt,
	.compat_getsockopt = compat_sock_common_getsockopt,
#endif
};

static struct net_proto_family inet6_family_ops = {
	.family = PF_INET6,
	.create = inet6_create,
	.owner	= THIS_MODULE,
};

/* Same as inet6_dgram_ops, sans udp_poll.  */
static const struct proto_ops inet6_sockraw_ops = {
	.family		   = PF_INET6,
	.owner		   = THIS_MODULE,
	.release	   = inet6_release,
	.bind		   = inet6_bind,
	.connect	   = inet_dgram_connect,	/* ok		*/
	.socketpair	   = sock_no_socketpair,	/* a do nothing	*/
	.accept		   = sock_no_accept,		/* a do nothing	*/
	.getname	   = inet6_getname,
	.poll		   = datagram_poll,		/* ok		*/
	.ioctl		   = inet6_ioctl,		/* must change  */
	.listen		   = sock_no_listen,		/* ok		*/
	.shutdown	   = inet_shutdown,		/* ok		*/
	.setsockopt	   = sock_common_setsockopt,	/* ok		*/
	.getsockopt	   = sock_common_getsockopt,	/* ok		*/
	.sendmsg	   = inet_sendmsg,		/* ok		*/
	.recvmsg	   = sock_common_recvmsg,	/* ok		*/
	.mmap		   = sock_no_mmap,
	.sendpage	   = sock_no_sendpage,
#ifdef CONFIG_COMPAT
	.compat_setsockopt = compat_sock_common_setsockopt,
	.compat_getsockopt = compat_sock_common_getsockopt,
#endif
};

static struct inet_protosw rawv6_protosw = {
	.type		= SOCK_RAW,
	.protocol	= IPPROTO_IP,	/* wild card */
	.prot		= &rawv6_prot,
	.ops		= &inet6_sockraw_ops,
	.capability	= CAP_NET_RAW,
	.no_check	= UDP_CSUM_DEFAULT,
	.flags		= INET_PROTOSW_REUSE,
};

void
inet6_register_protosw(struct inet_protosw *p)
{
	struct list_head *lh;
	struct inet_protosw *answer;
	int protocol = p->protocol;
	struct list_head *last_perm;

	spin_lock_bh(&inetsw6_lock);

	if (p->type >= SOCK_MAX)
		goto out_illegal;

	/* If we are trying to override a permanent protocol, bail. */
	answer = NULL;
	last_perm = &inetsw6[p->type];
	list_for_each(lh, &inetsw6[p->type]) {
		answer = list_entry(lh, struct inet_protosw, list);

		/* Check only the non-wild match. */
		if (INET_PROTOSW_PERMANENT & answer->flags) {
			if (protocol == answer->protocol)
				break;
			last_perm = lh;
		}

		answer = NULL;
	}
	if (answer)
		goto out_permanent;

	/* Add the new entry after the last permanent entry if any, so that
	 * the new entry does not override a permanent entry when matched with
	 * a wild-card protocol. But it is allowed to override any existing
	 * non-permanent entry.  This means that when we remove this entry, the
	 * system automatically returns to the old behavior.
	 */
	list_add_rcu(&p->list, last_perm);
out:
	spin_unlock_bh(&inetsw6_lock);
	return;

out_permanent:
	printk(KERN_ERR "Attempt to override permanent protocol %d.\n",
	       protocol);
	goto out;

out_illegal:
	printk(KERN_ERR
	       "Ignoring attempt to register invalid socket type %d.\n",
	       p->type);
	goto out;
}

EXPORT_SYMBOL(inet6_register_protosw);

void
inet6_unregister_protosw(struct inet_protosw *p)
{
	if (INET_PROTOSW_PERMANENT & p->flags) {
		printk(KERN_ERR
		       "Attempt to unregister permanent protocol %d.\n",
		       p->protocol);
	} else {
		spin_lock_bh(&inetsw6_lock);
		list_del_rcu(&p->list);
		spin_unlock_bh(&inetsw6_lock);

		synchronize_net();
	}
}

EXPORT_SYMBOL(inet6_unregister_protosw);

int inet6_sk_rebuild_header(struct sock *sk)
{
	int err;
	struct dst_entry *dst;
	struct ipv6_pinfo *np = inet6_sk(sk);

	dst = __sk_dst_check(sk, np->dst_cookie);

	if (dst == NULL) {
		struct inet_sock *inet = inet_sk(sk);
		struct in6_addr *final_p = NULL, final;
		struct flowi fl;

		memset(&fl, 0, sizeof(fl));
		fl.proto = sk->sk_protocol;
		ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
		ipv6_addr_copy(&fl.fl6_src, &np->saddr);
		fl.fl6_flowlabel = np->flow_label;
		fl.oif = sk->sk_bound_dev_if;
		fl.fl_ip_dport = inet->dport;
		fl.fl_ip_sport = inet->sport;
		security_sk_classify_flow(sk, &fl);

		if (np->opt && np->opt->srcrt) {
			struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt;
			ipv6_addr_copy(&final, &fl.fl6_dst);
			ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
			final_p = &final;
		}

		err = ip6_dst_lookup(sk, &dst, &fl);
		if (err) {
			sk->sk_route_caps = 0;
			return err;
		}
		if (final_p)
			ipv6_addr_copy(&fl.fl6_dst, final_p);

		if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
			sk->sk_err_soft = -err;
			return err;
		}

		__ip6_dst_store(sk, dst, NULL, NULL);
	}

	return 0;
}

EXPORT_SYMBOL_GPL(inet6_sk_rebuild_header);

int ipv6_opt_accepted(struct sock *sk, struct sk_buff *skb)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct inet6_skb_parm *opt = IP6CB(skb);

	if (np->rxopt.all) {
		if ((opt->hop && (np->rxopt.bits.hopopts ||
				  np->rxopt.bits.ohopopts)) ||
		    ((IPV6_FLOWINFO_MASK &
		      *(__be32 *)skb_network_header(skb)) &&
		     np->rxopt.bits.rxflow) ||
		    (opt->srcrt && (np->rxopt.bits.srcrt ||
		     np->rxopt.bits.osrcrt)) ||
		    ((opt->dst1 || opt->dst0) &&
		     (np->rxopt.bits.dstopts || np->rxopt.bits.odstopts)))
			return 1;
	}
	return 0;
}

EXPORT_SYMBOL_GPL(ipv6_opt_accepted);

static int __init init_ipv6_mibs(void)
{
	if (snmp_mib_init((void **)ipv6_statistics, sizeof (struct ipstats_mib),
			  __alignof__(struct ipstats_mib)) < 0)
		goto err_ip_mib;
	if (snmp_mib_init((void **)icmpv6_statistics, sizeof (struct icmpv6_mib),
			  __alignof__(struct icmpv6_mib)) < 0)
		goto err_icmp_mib;
	if (snmp_mib_init((void **)icmpv6msg_statistics,
	    sizeof (struct icmpv6msg_mib), __alignof__(struct icmpv6_mib)) < 0)
		goto err_icmpmsg_mib;
	if (snmp_mib_init((void **)udp_stats_in6, sizeof (struct udp_mib),
			  __alignof__(struct udp_mib)) < 0)
		goto err_udp_mib;
	if (snmp_mib_init((void **)udplite_stats_in6, sizeof (struct udp_mib),
			  __alignof__(struct udp_mib)) < 0)
		goto err_udplite_mib;
	return 0;

err_udplite_mib:
	snmp_mib_free((void **)udp_stats_in6);
err_udp_mib:
	snmp_mib_free((void **)icmpv6msg_statistics);
err_icmpmsg_mib:
	snmp_mib_free((void **)icmpv6_statistics);
err_icmp_mib:
	snmp_mib_free((void **)ipv6_statistics);
err_ip_mib:
	return -ENOMEM;

}

static void cleanup_ipv6_mibs(void)
{
	snmp_mib_free((void **)ipv6_statistics);
	snmp_mib_free((void **)icmpv6_statistics);
	snmp_mib_free((void **)icmpv6msg_statistics);
	snmp_mib_free((void **)udp_stats_in6);
	snmp_mib_free((void **)udplite_stats_in6);
}

static int __init inet6_init(void)
{
	struct sk_buff *dummy_skb;
	struct list_head *r;
	int err;

	BUILD_BUG_ON(sizeof(struct inet6_skb_parm) > sizeof(dummy_skb->cb));

#ifdef MODULE
#if 0 /* FIXME --RR */
	if (!mod_member_present(&__this_module, can_unload))
	  return -EINVAL;

	__this_module.can_unload = &ipv6_unload;
#endif
#endif

	err = proto_register(&tcpv6_prot, 1);
	if (err)
		goto out;

	err = proto_register(&udpv6_prot, 1);
	if (err)
		goto out_unregister_tcp_proto;

	err = proto_register(&udplitev6_prot, 1);
	if (err)
		goto out_unregister_udp_proto;

	err = proto_register(&rawv6_prot, 1);
	if (err)
		goto out_unregister_udplite_proto;


	/* Register the socket-side information for inet6_create.  */
	for(r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
		INIT_LIST_HEAD(r);

	/* We MUST register RAW sockets before we create the ICMP6,
	 * IGMP6, or NDISC control sockets.
	 */
	inet6_register_protosw(&rawv6_protosw);

	/* Register the family here so that the init calls below will
	 * be able to create sockets. (?? is this dangerous ??)
	 */
	err = sock_register(&inet6_family_ops);
	if (err)
		goto out_unregister_raw_proto;

	/* Initialise ipv6 mibs */
	err = init_ipv6_mibs();
	if (err)
		goto out_unregister_sock;

	/*
	 *	ipngwg API draft makes clear that the correct semantics
	 *	for TCP and UDP is to consider one TCP and UDP instance
	 *	in a host availiable by both INET and INET6 APIs and
	 *	able to communicate via both network protocols.
	 */

#ifdef CONFIG_SYSCTL
	ipv6_sysctl_register();
#endif
	err = icmpv6_init(&inet6_family_ops);
	if (err)
		goto icmp_fail;
	err = ndisc_init(&inet6_family_ops);
	if (err)
		goto ndisc_fail;
	err = igmp6_init(&inet6_family_ops);
	if (err)
		goto igmp_fail;
	err = ipv6_netfilter_init();
	if (err)
		goto netfilter_fail;
	/* Create /proc/foo6 entries. */
#ifdef CONFIG_PROC_FS
	err = -ENOMEM;
	if (raw6_proc_init())
		goto proc_raw6_fail;
	if (tcp6_proc_init())
		goto proc_tcp6_fail;
	if (udp6_proc_init())
		goto proc_udp6_fail;
	if (udplite6_proc_init())
		goto proc_udplite6_fail;
	if (ipv6_misc_proc_init())
		goto proc_misc6_fail;

	if (ac6_proc_init())
		goto proc_anycast6_fail;
	if (if6_proc_init())
		goto proc_if6_fail;
#endif
	ip6_route_init();
	ip6_flowlabel_init();
	err = addrconf_init();
	if (err)
		goto addrconf_fail;

	/* Init v6 extension headers. */
	ipv6_rthdr_init();
	ipv6_frag_init();
	ipv6_nodata_init();
	ipv6_destopt_init();

	/* Init v6 transport protocols. */
	udpv6_init();
	udplitev6_init();
	tcpv6_init();

	ipv6_packet_init();
	err = 0;
out:
	return err;

addrconf_fail:
	ip6_flowlabel_cleanup();
	ip6_route_cleanup();
#ifdef CONFIG_PROC_FS
	if6_proc_exit();
proc_if6_fail:
	ac6_proc_exit();
proc_anycast6_fail:
	ipv6_misc_proc_exit();
proc_misc6_fail:
	udplite6_proc_exit();
proc_udplite6_fail:
	udp6_proc_exit();
proc_udp6_fail:
	tcp6_proc_exit();
proc_tcp6_fail:
	raw6_proc_exit();
proc_raw6_fail:
#endif
	ipv6_netfilter_fini();
netfilter_fail:
	igmp6_cleanup();
igmp_fail:
	ndisc_cleanup();
ndisc_fail:
	icmpv6_cleanup();
icmp_fail:
#ifdef CONFIG_SYSCTL
	ipv6_sysctl_unregister();
#endif
	cleanup_ipv6_mibs();
out_unregister_sock:
	sock_unregister(PF_INET6);
out_unregister_raw_proto:
	proto_unregister(&rawv6_prot);
out_unregister_udplite_proto:
	proto_unregister(&udplitev6_prot);
out_unregister_udp_proto:
	proto_unregister(&udpv6_prot);
out_unregister_tcp_proto:
	proto_unregister(&tcpv6_prot);
	goto out;
}
module_init(inet6_init);

static void __exit inet6_exit(void)
{
	/* First of all disallow new sockets creation. */
	sock_unregister(PF_INET6);
	/* Disallow any further netlink messages */
	rtnl_unregister_all(PF_INET6);

	/* Cleanup code parts. */
	ipv6_packet_cleanup();

	addrconf_cleanup();
	ip6_flowlabel_cleanup();
	ip6_route_cleanup();
#ifdef CONFIG_PROC_FS

	/* Cleanup code parts. */
	if6_proc_exit();
	ac6_proc_exit();
	ipv6_misc_proc_exit();
	udplite6_proc_exit();
	udp6_proc_exit();
	tcp6_proc_exit();
	raw6_proc_exit();
#endif
	ipv6_netfilter_fini();
	igmp6_cleanup();
	ndisc_cleanup();
	icmpv6_cleanup();
#ifdef CONFIG_SYSCTL
	ipv6_sysctl_unregister();
#endif
	cleanup_ipv6_mibs();
	proto_unregister(&rawv6_prot);
	proto_unregister(&udplitev6_prot);
	proto_unregister(&udpv6_prot);
	proto_unregister(&tcpv6_prot);
}
module_exit(inet6_exit);

MODULE_ALIAS_NETPROTO(PF_INET6);