|  | /* | 
|  | *	TCP over IPv6 | 
|  | *	Linux INET6 implementation | 
|  | * | 
|  | *	Authors: | 
|  | *	Pedro Roque		<roque@di.fc.ul.pt> | 
|  | * | 
|  | *	$Id: tcp_ipv6.c,v 1.144 2002/02/01 22:01:04 davem Exp $ | 
|  | * | 
|  | *	Based on: | 
|  | *	linux/net/ipv4/tcp.c | 
|  | *	linux/net/ipv4/tcp_input.c | 
|  | *	linux/net/ipv4/tcp_output.c | 
|  | * | 
|  | *	Fixes: | 
|  | *	Hideaki YOSHIFUJI	:	sin6_scope_id support | 
|  | *	YOSHIFUJI Hideaki @USAGI and:	Support IPV6_V6ONLY socket option, which | 
|  | *	Alexey Kuznetsov		allow both IPv4 and IPv6 sockets to bind | 
|  | *					a single port at the same time. | 
|  | *	YOSHIFUJI Hideaki @USAGI:	convert /proc/net/tcp6 to seq_file. | 
|  | * | 
|  | *	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. | 
|  | */ | 
|  |  | 
|  | #include <linux/module.h> | 
|  | #include <linux/config.h> | 
|  | #include <linux/errno.h> | 
|  | #include <linux/types.h> | 
|  | #include <linux/socket.h> | 
|  | #include <linux/sockios.h> | 
|  | #include <linux/net.h> | 
|  | #include <linux/jiffies.h> | 
|  | #include <linux/in.h> | 
|  | #include <linux/in6.h> | 
|  | #include <linux/netdevice.h> | 
|  | #include <linux/init.h> | 
|  | #include <linux/jhash.h> | 
|  | #include <linux/ipsec.h> | 
|  | #include <linux/times.h> | 
|  |  | 
|  | #include <linux/ipv6.h> | 
|  | #include <linux/icmpv6.h> | 
|  | #include <linux/random.h> | 
|  |  | 
|  | #include <net/tcp.h> | 
|  | #include <net/ndisc.h> | 
|  | #include <net/inet6_hashtables.h> | 
|  | #include <net/inet6_connection_sock.h> | 
|  | #include <net/ipv6.h> | 
|  | #include <net/transp_v6.h> | 
|  | #include <net/addrconf.h> | 
|  | #include <net/ip6_route.h> | 
|  | #include <net/ip6_checksum.h> | 
|  | #include <net/inet_ecn.h> | 
|  | #include <net/protocol.h> | 
|  | #include <net/xfrm.h> | 
|  | #include <net/addrconf.h> | 
|  | #include <net/snmp.h> | 
|  | #include <net/dsfield.h> | 
|  | #include <net/timewait_sock.h> | 
|  |  | 
|  | #include <asm/uaccess.h> | 
|  |  | 
|  | #include <linux/proc_fs.h> | 
|  | #include <linux/seq_file.h> | 
|  |  | 
|  | /* Socket used for sending RSTs and ACKs */ | 
|  | static struct socket *tcp6_socket; | 
|  |  | 
|  | static void	tcp_v6_send_reset(struct sk_buff *skb); | 
|  | static void	tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req); | 
|  | static void	tcp_v6_send_check(struct sock *sk, int len, | 
|  | struct sk_buff *skb); | 
|  |  | 
|  | static int	tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb); | 
|  |  | 
|  | static struct inet_connection_sock_af_ops ipv6_mapped; | 
|  | static struct inet_connection_sock_af_ops ipv6_specific; | 
|  |  | 
|  | static int tcp_v6_get_port(struct sock *sk, unsigned short snum) | 
|  | { | 
|  | return inet_csk_get_port(&tcp_hashinfo, sk, snum, | 
|  | inet6_csk_bind_conflict); | 
|  | } | 
|  |  | 
|  | static void tcp_v6_hash(struct sock *sk) | 
|  | { | 
|  | if (sk->sk_state != TCP_CLOSE) { | 
|  | if (inet_csk(sk)->icsk_af_ops == &ipv6_mapped) { | 
|  | tcp_prot.hash(sk); | 
|  | return; | 
|  | } | 
|  | local_bh_disable(); | 
|  | __inet6_hash(&tcp_hashinfo, sk); | 
|  | local_bh_enable(); | 
|  | } | 
|  | } | 
|  |  | 
|  | static __inline__ u16 tcp_v6_check(struct tcphdr *th, int len, | 
|  | struct in6_addr *saddr, | 
|  | struct in6_addr *daddr, | 
|  | unsigned long base) | 
|  | { | 
|  | return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base); | 
|  | } | 
|  |  | 
|  | static __u32 tcp_v6_init_sequence(struct sock *sk, struct sk_buff *skb) | 
|  | { | 
|  | if (skb->protocol == htons(ETH_P_IPV6)) { | 
|  | return secure_tcpv6_sequence_number(skb->nh.ipv6h->daddr.s6_addr32, | 
|  | skb->nh.ipv6h->saddr.s6_addr32, | 
|  | skb->h.th->dest, | 
|  | skb->h.th->source); | 
|  | } else { | 
|  | return secure_tcp_sequence_number(skb->nh.iph->daddr, | 
|  | skb->nh.iph->saddr, | 
|  | skb->h.th->dest, | 
|  | skb->h.th->source); | 
|  | } | 
|  | } | 
|  |  | 
|  | static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, | 
|  | int addr_len) | 
|  | { | 
|  | struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr; | 
|  | struct inet_sock *inet = inet_sk(sk); | 
|  | struct inet_connection_sock *icsk = inet_csk(sk); | 
|  | struct ipv6_pinfo *np = inet6_sk(sk); | 
|  | struct tcp_sock *tp = tcp_sk(sk); | 
|  | struct in6_addr *saddr = NULL, *final_p = NULL, final; | 
|  | struct flowi fl; | 
|  | struct dst_entry *dst; | 
|  | int addr_type; | 
|  | int err; | 
|  |  | 
|  | if (addr_len < SIN6_LEN_RFC2133) | 
|  | return -EINVAL; | 
|  |  | 
|  | if (usin->sin6_family != AF_INET6) | 
|  | return(-EAFNOSUPPORT); | 
|  |  | 
|  | memset(&fl, 0, sizeof(fl)); | 
|  |  | 
|  | if (np->sndflow) { | 
|  | fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK; | 
|  | IP6_ECN_flow_init(fl.fl6_flowlabel); | 
|  | if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) { | 
|  | struct ip6_flowlabel *flowlabel; | 
|  | flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel); | 
|  | if (flowlabel == NULL) | 
|  | return -EINVAL; | 
|  | ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst); | 
|  | fl6_sock_release(flowlabel); | 
|  | } | 
|  | } | 
|  |  | 
|  | /* | 
|  | *	connect() to INADDR_ANY means loopback (BSD'ism). | 
|  | */ | 
|  |  | 
|  | if(ipv6_addr_any(&usin->sin6_addr)) | 
|  | usin->sin6_addr.s6_addr[15] = 0x1; | 
|  |  | 
|  | addr_type = ipv6_addr_type(&usin->sin6_addr); | 
|  |  | 
|  | if(addr_type & IPV6_ADDR_MULTICAST) | 
|  | return -ENETUNREACH; | 
|  |  | 
|  | if (addr_type&IPV6_ADDR_LINKLOCAL) { | 
|  | if (addr_len >= sizeof(struct sockaddr_in6) && | 
|  | usin->sin6_scope_id) { | 
|  | /* If interface is set while binding, indices | 
|  | * must coincide. | 
|  | */ | 
|  | if (sk->sk_bound_dev_if && | 
|  | sk->sk_bound_dev_if != usin->sin6_scope_id) | 
|  | return -EINVAL; | 
|  |  | 
|  | sk->sk_bound_dev_if = usin->sin6_scope_id; | 
|  | } | 
|  |  | 
|  | /* Connect to link-local address requires an interface */ | 
|  | if (!sk->sk_bound_dev_if) | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | if (tp->rx_opt.ts_recent_stamp && | 
|  | !ipv6_addr_equal(&np->daddr, &usin->sin6_addr)) { | 
|  | tp->rx_opt.ts_recent = 0; | 
|  | tp->rx_opt.ts_recent_stamp = 0; | 
|  | tp->write_seq = 0; | 
|  | } | 
|  |  | 
|  | ipv6_addr_copy(&np->daddr, &usin->sin6_addr); | 
|  | np->flow_label = fl.fl6_flowlabel; | 
|  |  | 
|  | /* | 
|  | *	TCP over IPv4 | 
|  | */ | 
|  |  | 
|  | if (addr_type == IPV6_ADDR_MAPPED) { | 
|  | u32 exthdrlen = icsk->icsk_ext_hdr_len; | 
|  | struct sockaddr_in sin; | 
|  |  | 
|  | SOCK_DEBUG(sk, "connect: ipv4 mapped\n"); | 
|  |  | 
|  | if (__ipv6_only_sock(sk)) | 
|  | return -ENETUNREACH; | 
|  |  | 
|  | sin.sin_family = AF_INET; | 
|  | sin.sin_port = usin->sin6_port; | 
|  | sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3]; | 
|  |  | 
|  | icsk->icsk_af_ops = &ipv6_mapped; | 
|  | sk->sk_backlog_rcv = tcp_v4_do_rcv; | 
|  |  | 
|  | err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin)); | 
|  |  | 
|  | if (err) { | 
|  | icsk->icsk_ext_hdr_len = exthdrlen; | 
|  | icsk->icsk_af_ops = &ipv6_specific; | 
|  | sk->sk_backlog_rcv = tcp_v6_do_rcv; | 
|  | goto failure; | 
|  | } else { | 
|  | ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF), | 
|  | inet->saddr); | 
|  | ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF), | 
|  | inet->rcv_saddr); | 
|  | } | 
|  |  | 
|  | return err; | 
|  | } | 
|  |  | 
|  | if (!ipv6_addr_any(&np->rcv_saddr)) | 
|  | saddr = &np->rcv_saddr; | 
|  |  | 
|  | fl.proto = IPPROTO_TCP; | 
|  | ipv6_addr_copy(&fl.fl6_dst, &np->daddr); | 
|  | ipv6_addr_copy(&fl.fl6_src, | 
|  | (saddr ? saddr : &np->saddr)); | 
|  | fl.oif = sk->sk_bound_dev_if; | 
|  | fl.fl_ip_dport = usin->sin6_port; | 
|  | fl.fl_ip_sport = inet->sport; | 
|  |  | 
|  | 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) | 
|  | goto failure; | 
|  | if (final_p) | 
|  | ipv6_addr_copy(&fl.fl6_dst, final_p); | 
|  |  | 
|  | if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) | 
|  | goto failure; | 
|  |  | 
|  | if (saddr == NULL) { | 
|  | saddr = &fl.fl6_src; | 
|  | ipv6_addr_copy(&np->rcv_saddr, saddr); | 
|  | } | 
|  |  | 
|  | /* set the source address */ | 
|  | ipv6_addr_copy(&np->saddr, saddr); | 
|  | inet->rcv_saddr = LOOPBACK4_IPV6; | 
|  |  | 
|  | ip6_dst_store(sk, dst, NULL); | 
|  | sk->sk_route_caps = dst->dev->features & | 
|  | ~(NETIF_F_IP_CSUM | NETIF_F_TSO); | 
|  |  | 
|  | icsk->icsk_ext_hdr_len = 0; | 
|  | if (np->opt) | 
|  | icsk->icsk_ext_hdr_len = (np->opt->opt_flen + | 
|  | np->opt->opt_nflen); | 
|  |  | 
|  | tp->rx_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr); | 
|  |  | 
|  | inet->dport = usin->sin6_port; | 
|  |  | 
|  | tcp_set_state(sk, TCP_SYN_SENT); | 
|  | err = inet6_hash_connect(&tcp_death_row, sk); | 
|  | if (err) | 
|  | goto late_failure; | 
|  |  | 
|  | if (!tp->write_seq) | 
|  | tp->write_seq = secure_tcpv6_sequence_number(np->saddr.s6_addr32, | 
|  | np->daddr.s6_addr32, | 
|  | inet->sport, | 
|  | inet->dport); | 
|  |  | 
|  | err = tcp_connect(sk); | 
|  | if (err) | 
|  | goto late_failure; | 
|  |  | 
|  | return 0; | 
|  |  | 
|  | late_failure: | 
|  | tcp_set_state(sk, TCP_CLOSE); | 
|  | __sk_dst_reset(sk); | 
|  | failure: | 
|  | inet->dport = 0; | 
|  | sk->sk_route_caps = 0; | 
|  | return err; | 
|  | } | 
|  |  | 
|  | static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, | 
|  | int type, int code, int offset, __u32 info) | 
|  | { | 
|  | struct ipv6hdr *hdr = (struct ipv6hdr*)skb->data; | 
|  | const struct tcphdr *th = (struct tcphdr *)(skb->data+offset); | 
|  | struct ipv6_pinfo *np; | 
|  | struct sock *sk; | 
|  | int err; | 
|  | struct tcp_sock *tp; | 
|  | __u32 seq; | 
|  |  | 
|  | sk = inet6_lookup(&tcp_hashinfo, &hdr->daddr, th->dest, &hdr->saddr, | 
|  | th->source, skb->dev->ifindex); | 
|  |  | 
|  | if (sk == NULL) { | 
|  | ICMP6_INC_STATS_BH(__in6_dev_get(skb->dev), ICMP6_MIB_INERRORS); | 
|  | return; | 
|  | } | 
|  |  | 
|  | if (sk->sk_state == TCP_TIME_WAIT) { | 
|  | inet_twsk_put((struct inet_timewait_sock *)sk); | 
|  | return; | 
|  | } | 
|  |  | 
|  | bh_lock_sock(sk); | 
|  | if (sock_owned_by_user(sk)) | 
|  | NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS); | 
|  |  | 
|  | if (sk->sk_state == TCP_CLOSE) | 
|  | goto out; | 
|  |  | 
|  | tp = tcp_sk(sk); | 
|  | seq = ntohl(th->seq); | 
|  | if (sk->sk_state != TCP_LISTEN && | 
|  | !between(seq, tp->snd_una, tp->snd_nxt)) { | 
|  | NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | np = inet6_sk(sk); | 
|  |  | 
|  | if (type == ICMPV6_PKT_TOOBIG) { | 
|  | struct dst_entry *dst = NULL; | 
|  |  | 
|  | if (sock_owned_by_user(sk)) | 
|  | goto out; | 
|  | if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) | 
|  | goto out; | 
|  |  | 
|  | /* icmp should have updated the destination cache entry */ | 
|  | dst = __sk_dst_check(sk, np->dst_cookie); | 
|  |  | 
|  | if (dst == NULL) { | 
|  | struct inet_sock *inet = inet_sk(sk); | 
|  | struct flowi fl; | 
|  |  | 
|  | /* BUGGG_FUTURE: Again, it is not clear how | 
|  | to handle rthdr case. Ignore this complexity | 
|  | for now. | 
|  | */ | 
|  | memset(&fl, 0, sizeof(fl)); | 
|  | fl.proto = IPPROTO_TCP; | 
|  | ipv6_addr_copy(&fl.fl6_dst, &np->daddr); | 
|  | ipv6_addr_copy(&fl.fl6_src, &np->saddr); | 
|  | fl.oif = sk->sk_bound_dev_if; | 
|  | fl.fl_ip_dport = inet->dport; | 
|  | fl.fl_ip_sport = inet->sport; | 
|  |  | 
|  | if ((err = ip6_dst_lookup(sk, &dst, &fl))) { | 
|  | sk->sk_err_soft = -err; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) { | 
|  | sk->sk_err_soft = -err; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | } else | 
|  | dst_hold(dst); | 
|  |  | 
|  | if (inet_csk(sk)->icsk_pmtu_cookie > dst_mtu(dst)) { | 
|  | tcp_sync_mss(sk, dst_mtu(dst)); | 
|  | tcp_simple_retransmit(sk); | 
|  | } /* else let the usual retransmit timer handle it */ | 
|  | dst_release(dst); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | icmpv6_err_convert(type, code, &err); | 
|  |  | 
|  | /* Might be for an request_sock */ | 
|  | switch (sk->sk_state) { | 
|  | struct request_sock *req, **prev; | 
|  | case TCP_LISTEN: | 
|  | if (sock_owned_by_user(sk)) | 
|  | goto out; | 
|  |  | 
|  | req = inet6_csk_search_req(sk, &prev, th->dest, &hdr->daddr, | 
|  | &hdr->saddr, inet6_iif(skb)); | 
|  | if (!req) | 
|  | goto out; | 
|  |  | 
|  | /* ICMPs are not backlogged, hence we cannot get | 
|  | * an established socket here. | 
|  | */ | 
|  | BUG_TRAP(req->sk == NULL); | 
|  |  | 
|  | if (seq != tcp_rsk(req)->snt_isn) { | 
|  | NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS); | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | inet_csk_reqsk_queue_drop(sk, req, prev); | 
|  | goto out; | 
|  |  | 
|  | case TCP_SYN_SENT: | 
|  | case TCP_SYN_RECV:  /* Cannot happen. | 
|  | It can, it SYNs are crossed. --ANK */ | 
|  | if (!sock_owned_by_user(sk)) { | 
|  | TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS); | 
|  | sk->sk_err = err; | 
|  | sk->sk_error_report(sk);		/* Wake people up to see the error (see connect in sock.c) */ | 
|  |  | 
|  | tcp_done(sk); | 
|  | } else | 
|  | sk->sk_err_soft = err; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | if (!sock_owned_by_user(sk) && np->recverr) { | 
|  | sk->sk_err = err; | 
|  | sk->sk_error_report(sk); | 
|  | } else | 
|  | sk->sk_err_soft = err; | 
|  |  | 
|  | out: | 
|  | bh_unlock_sock(sk); | 
|  | sock_put(sk); | 
|  | } | 
|  |  | 
|  |  | 
|  | static int tcp_v6_send_synack(struct sock *sk, struct request_sock *req, | 
|  | struct dst_entry *dst) | 
|  | { | 
|  | struct inet6_request_sock *treq = inet6_rsk(req); | 
|  | struct ipv6_pinfo *np = inet6_sk(sk); | 
|  | struct sk_buff * skb; | 
|  | struct ipv6_txoptions *opt = NULL; | 
|  | struct in6_addr * final_p = NULL, final; | 
|  | struct flowi fl; | 
|  | int err = -1; | 
|  |  | 
|  | memset(&fl, 0, sizeof(fl)); | 
|  | fl.proto = IPPROTO_TCP; | 
|  | ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr); | 
|  | ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr); | 
|  | fl.fl6_flowlabel = 0; | 
|  | fl.oif = treq->iif; | 
|  | fl.fl_ip_dport = inet_rsk(req)->rmt_port; | 
|  | fl.fl_ip_sport = inet_sk(sk)->sport; | 
|  |  | 
|  | if (dst == NULL) { | 
|  | opt = np->opt; | 
|  | if (opt == NULL && | 
|  | np->rxopt.bits.osrcrt == 2 && | 
|  | treq->pktopts) { | 
|  | struct sk_buff *pktopts = treq->pktopts; | 
|  | struct inet6_skb_parm *rxopt = IP6CB(pktopts); | 
|  | if (rxopt->srcrt) | 
|  | opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr*)(pktopts->nh.raw + rxopt->srcrt)); | 
|  | } | 
|  |  | 
|  | if (opt && opt->srcrt) { | 
|  | struct rt0_hdr *rt0 = (struct rt0_hdr *) 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) | 
|  | goto done; | 
|  | if (final_p) | 
|  | ipv6_addr_copy(&fl.fl6_dst, final_p); | 
|  | if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) | 
|  | goto done; | 
|  | } | 
|  |  | 
|  | skb = tcp_make_synack(sk, dst, req); | 
|  | if (skb) { | 
|  | struct tcphdr *th = skb->h.th; | 
|  |  | 
|  | th->check = tcp_v6_check(th, skb->len, | 
|  | &treq->loc_addr, &treq->rmt_addr, | 
|  | csum_partial((char *)th, skb->len, skb->csum)); | 
|  |  | 
|  | ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr); | 
|  | err = ip6_xmit(sk, skb, &fl, opt, 0); | 
|  | if (err == NET_XMIT_CN) | 
|  | err = 0; | 
|  | } | 
|  |  | 
|  | done: | 
|  | if (opt && opt != np->opt) | 
|  | sock_kfree_s(sk, opt, opt->tot_len); | 
|  | dst_release(dst); | 
|  | return err; | 
|  | } | 
|  |  | 
|  | static void tcp_v6_reqsk_destructor(struct request_sock *req) | 
|  | { | 
|  | if (inet6_rsk(req)->pktopts) | 
|  | kfree_skb(inet6_rsk(req)->pktopts); | 
|  | } | 
|  |  | 
|  | static struct request_sock_ops tcp6_request_sock_ops = { | 
|  | .family		=	AF_INET6, | 
|  | .obj_size	=	sizeof(struct tcp6_request_sock), | 
|  | .rtx_syn_ack	=	tcp_v6_send_synack, | 
|  | .send_ack	=	tcp_v6_reqsk_send_ack, | 
|  | .destructor	=	tcp_v6_reqsk_destructor, | 
|  | .send_reset	=	tcp_v6_send_reset | 
|  | }; | 
|  |  | 
|  | static struct timewait_sock_ops tcp6_timewait_sock_ops = { | 
|  | .twsk_obj_size	= sizeof(struct tcp6_timewait_sock), | 
|  | .twsk_unique	= tcp_twsk_unique, | 
|  | }; | 
|  |  | 
|  | static void tcp_v6_send_check(struct sock *sk, int len, struct sk_buff *skb) | 
|  | { | 
|  | struct ipv6_pinfo *np = inet6_sk(sk); | 
|  | struct tcphdr *th = skb->h.th; | 
|  |  | 
|  | if (skb->ip_summed == CHECKSUM_HW) { | 
|  | th->check = ~csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP,  0); | 
|  | skb->csum = offsetof(struct tcphdr, check); | 
|  | } else { | 
|  | th->check = csum_ipv6_magic(&np->saddr, &np->daddr, len, IPPROTO_TCP, | 
|  | csum_partial((char *)th, th->doff<<2, | 
|  | skb->csum)); | 
|  | } | 
|  | } | 
|  |  | 
|  |  | 
|  | static void tcp_v6_send_reset(struct sk_buff *skb) | 
|  | { | 
|  | struct tcphdr *th = skb->h.th, *t1; | 
|  | struct sk_buff *buff; | 
|  | struct flowi fl; | 
|  |  | 
|  | if (th->rst) | 
|  | return; | 
|  |  | 
|  | if (!ipv6_unicast_destination(skb)) | 
|  | return; | 
|  |  | 
|  | /* | 
|  | * We need to grab some memory, and put together an RST, | 
|  | * and then put it into the queue to be sent. | 
|  | */ | 
|  |  | 
|  | buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr), | 
|  | GFP_ATOMIC); | 
|  | if (buff == NULL) | 
|  | return; | 
|  |  | 
|  | skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + sizeof(struct tcphdr)); | 
|  |  | 
|  | t1 = (struct tcphdr *) skb_push(buff,sizeof(struct tcphdr)); | 
|  |  | 
|  | /* Swap the send and the receive. */ | 
|  | memset(t1, 0, sizeof(*t1)); | 
|  | t1->dest = th->source; | 
|  | t1->source = th->dest; | 
|  | t1->doff = sizeof(*t1)/4; | 
|  | t1->rst = 1; | 
|  |  | 
|  | if(th->ack) { | 
|  | t1->seq = th->ack_seq; | 
|  | } else { | 
|  | t1->ack = 1; | 
|  | t1->ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin | 
|  | + skb->len - (th->doff<<2)); | 
|  | } | 
|  |  | 
|  | buff->csum = csum_partial((char *)t1, sizeof(*t1), 0); | 
|  |  | 
|  | memset(&fl, 0, sizeof(fl)); | 
|  | ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr); | 
|  | ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr); | 
|  |  | 
|  | t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst, | 
|  | sizeof(*t1), IPPROTO_TCP, | 
|  | buff->csum); | 
|  |  | 
|  | fl.proto = IPPROTO_TCP; | 
|  | fl.oif = inet6_iif(skb); | 
|  | fl.fl_ip_dport = t1->dest; | 
|  | fl.fl_ip_sport = t1->source; | 
|  |  | 
|  | /* sk = NULL, but it is safe for now. RST socket required. */ | 
|  | if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) { | 
|  |  | 
|  | if (xfrm_lookup(&buff->dst, &fl, NULL, 0) >= 0) { | 
|  | ip6_xmit(tcp6_socket->sk, buff, &fl, NULL, 0); | 
|  | TCP_INC_STATS_BH(TCP_MIB_OUTSEGS); | 
|  | TCP_INC_STATS_BH(TCP_MIB_OUTRSTS); | 
|  | return; | 
|  | } | 
|  | } | 
|  |  | 
|  | kfree_skb(buff); | 
|  | } | 
|  |  | 
|  | static void tcp_v6_send_ack(struct sk_buff *skb, u32 seq, u32 ack, u32 win, u32 ts) | 
|  | { | 
|  | struct tcphdr *th = skb->h.th, *t1; | 
|  | struct sk_buff *buff; | 
|  | struct flowi fl; | 
|  | int tot_len = sizeof(struct tcphdr); | 
|  |  | 
|  | if (ts) | 
|  | tot_len += 3*4; | 
|  |  | 
|  | buff = alloc_skb(MAX_HEADER + sizeof(struct ipv6hdr) + tot_len, | 
|  | GFP_ATOMIC); | 
|  | if (buff == NULL) | 
|  | return; | 
|  |  | 
|  | skb_reserve(buff, MAX_HEADER + sizeof(struct ipv6hdr) + tot_len); | 
|  |  | 
|  | t1 = (struct tcphdr *) skb_push(buff,tot_len); | 
|  |  | 
|  | /* Swap the send and the receive. */ | 
|  | memset(t1, 0, sizeof(*t1)); | 
|  | t1->dest = th->source; | 
|  | t1->source = th->dest; | 
|  | t1->doff = tot_len/4; | 
|  | t1->seq = htonl(seq); | 
|  | t1->ack_seq = htonl(ack); | 
|  | t1->ack = 1; | 
|  | t1->window = htons(win); | 
|  |  | 
|  | if (ts) { | 
|  | u32 *ptr = (u32*)(t1 + 1); | 
|  | *ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | | 
|  | (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP); | 
|  | *ptr++ = htonl(tcp_time_stamp); | 
|  | *ptr = htonl(ts); | 
|  | } | 
|  |  | 
|  | buff->csum = csum_partial((char *)t1, tot_len, 0); | 
|  |  | 
|  | memset(&fl, 0, sizeof(fl)); | 
|  | ipv6_addr_copy(&fl.fl6_dst, &skb->nh.ipv6h->saddr); | 
|  | ipv6_addr_copy(&fl.fl6_src, &skb->nh.ipv6h->daddr); | 
|  |  | 
|  | t1->check = csum_ipv6_magic(&fl.fl6_src, &fl.fl6_dst, | 
|  | tot_len, IPPROTO_TCP, | 
|  | buff->csum); | 
|  |  | 
|  | fl.proto = IPPROTO_TCP; | 
|  | fl.oif = inet6_iif(skb); | 
|  | fl.fl_ip_dport = t1->dest; | 
|  | fl.fl_ip_sport = t1->source; | 
|  |  | 
|  | if (!ip6_dst_lookup(NULL, &buff->dst, &fl)) { | 
|  | if (xfrm_lookup(&buff->dst, &fl, NULL, 0) >= 0) { | 
|  | ip6_xmit(tcp6_socket->sk, buff, &fl, NULL, 0); | 
|  | TCP_INC_STATS_BH(TCP_MIB_OUTSEGS); | 
|  | return; | 
|  | } | 
|  | } | 
|  |  | 
|  | kfree_skb(buff); | 
|  | } | 
|  |  | 
|  | static void tcp_v6_timewait_ack(struct sock *sk, struct sk_buff *skb) | 
|  | { | 
|  | struct inet_timewait_sock *tw = inet_twsk(sk); | 
|  | const struct tcp_timewait_sock *tcptw = tcp_twsk(sk); | 
|  |  | 
|  | tcp_v6_send_ack(skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, | 
|  | tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, | 
|  | tcptw->tw_ts_recent); | 
|  |  | 
|  | inet_twsk_put(tw); | 
|  | } | 
|  |  | 
|  | static void tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req) | 
|  | { | 
|  | tcp_v6_send_ack(skb, tcp_rsk(req)->snt_isn + 1, tcp_rsk(req)->rcv_isn + 1, req->rcv_wnd, req->ts_recent); | 
|  | } | 
|  |  | 
|  |  | 
|  | static struct sock *tcp_v6_hnd_req(struct sock *sk,struct sk_buff *skb) | 
|  | { | 
|  | struct request_sock *req, **prev; | 
|  | const struct tcphdr *th = skb->h.th; | 
|  | struct sock *nsk; | 
|  |  | 
|  | /* Find possible connection requests. */ | 
|  | req = inet6_csk_search_req(sk, &prev, th->source, | 
|  | &skb->nh.ipv6h->saddr, | 
|  | &skb->nh.ipv6h->daddr, inet6_iif(skb)); | 
|  | if (req) | 
|  | return tcp_check_req(sk, skb, req, prev); | 
|  |  | 
|  | nsk = __inet6_lookup_established(&tcp_hashinfo, &skb->nh.ipv6h->saddr, | 
|  | th->source, &skb->nh.ipv6h->daddr, | 
|  | ntohs(th->dest), inet6_iif(skb)); | 
|  |  | 
|  | if (nsk) { | 
|  | if (nsk->sk_state != TCP_TIME_WAIT) { | 
|  | bh_lock_sock(nsk); | 
|  | return nsk; | 
|  | } | 
|  | inet_twsk_put((struct inet_timewait_sock *)nsk); | 
|  | return NULL; | 
|  | } | 
|  |  | 
|  | #if 0 /*def CONFIG_SYN_COOKIES*/ | 
|  | if (!th->rst && !th->syn && th->ack) | 
|  | sk = cookie_v6_check(sk, skb, &(IPCB(skb)->opt)); | 
|  | #endif | 
|  | return sk; | 
|  | } | 
|  |  | 
|  | /* FIXME: this is substantially similar to the ipv4 code. | 
|  | * Can some kind of merge be done? -- erics | 
|  | */ | 
|  | static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) | 
|  | { | 
|  | struct inet6_request_sock *treq; | 
|  | struct ipv6_pinfo *np = inet6_sk(sk); | 
|  | struct tcp_options_received tmp_opt; | 
|  | struct tcp_sock *tp = tcp_sk(sk); | 
|  | struct request_sock *req = NULL; | 
|  | __u32 isn = TCP_SKB_CB(skb)->when; | 
|  |  | 
|  | if (skb->protocol == htons(ETH_P_IP)) | 
|  | return tcp_v4_conn_request(sk, skb); | 
|  |  | 
|  | if (!ipv6_unicast_destination(skb)) | 
|  | goto drop; | 
|  |  | 
|  | /* | 
|  | *	There are no SYN attacks on IPv6, yet... | 
|  | */ | 
|  | if (inet_csk_reqsk_queue_is_full(sk) && !isn) { | 
|  | if (net_ratelimit()) | 
|  | printk(KERN_INFO "TCPv6: dropping request, synflood is possible\n"); | 
|  | goto drop; | 
|  | } | 
|  |  | 
|  | if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1) | 
|  | goto drop; | 
|  |  | 
|  | req = inet6_reqsk_alloc(&tcp6_request_sock_ops); | 
|  | if (req == NULL) | 
|  | goto drop; | 
|  |  | 
|  | tcp_clear_options(&tmp_opt); | 
|  | tmp_opt.mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) - sizeof(struct ipv6hdr); | 
|  | tmp_opt.user_mss = tp->rx_opt.user_mss; | 
|  |  | 
|  | tcp_parse_options(skb, &tmp_opt, 0); | 
|  |  | 
|  | tmp_opt.tstamp_ok = tmp_opt.saw_tstamp; | 
|  | tcp_openreq_init(req, &tmp_opt, skb); | 
|  |  | 
|  | treq = inet6_rsk(req); | 
|  | ipv6_addr_copy(&treq->rmt_addr, &skb->nh.ipv6h->saddr); | 
|  | ipv6_addr_copy(&treq->loc_addr, &skb->nh.ipv6h->daddr); | 
|  | TCP_ECN_create_request(req, skb->h.th); | 
|  | treq->pktopts = NULL; | 
|  | if (ipv6_opt_accepted(sk, skb) || | 
|  | np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo || | 
|  | np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) { | 
|  | atomic_inc(&skb->users); | 
|  | treq->pktopts = skb; | 
|  | } | 
|  | treq->iif = sk->sk_bound_dev_if; | 
|  |  | 
|  | /* So that link locals have meaning */ | 
|  | if (!sk->sk_bound_dev_if && | 
|  | ipv6_addr_type(&treq->rmt_addr) & IPV6_ADDR_LINKLOCAL) | 
|  | treq->iif = inet6_iif(skb); | 
|  |  | 
|  | if (isn == 0) | 
|  | isn = tcp_v6_init_sequence(sk,skb); | 
|  |  | 
|  | tcp_rsk(req)->snt_isn = isn; | 
|  |  | 
|  | if (tcp_v6_send_synack(sk, req, NULL)) | 
|  | goto drop; | 
|  |  | 
|  | inet6_csk_reqsk_queue_hash_add(sk, req, TCP_TIMEOUT_INIT); | 
|  | return 0; | 
|  |  | 
|  | drop: | 
|  | if (req) | 
|  | reqsk_free(req); | 
|  |  | 
|  | TCP_INC_STATS_BH(TCP_MIB_ATTEMPTFAILS); | 
|  | return 0; /* don't send reset */ | 
|  | } | 
|  |  | 
|  | static struct sock * tcp_v6_syn_recv_sock(struct sock *sk, struct sk_buff *skb, | 
|  | struct request_sock *req, | 
|  | struct dst_entry *dst) | 
|  | { | 
|  | struct inet6_request_sock *treq = inet6_rsk(req); | 
|  | struct ipv6_pinfo *newnp, *np = inet6_sk(sk); | 
|  | struct tcp6_sock *newtcp6sk; | 
|  | struct inet_sock *newinet; | 
|  | struct tcp_sock *newtp; | 
|  | struct sock *newsk; | 
|  | struct ipv6_txoptions *opt; | 
|  |  | 
|  | if (skb->protocol == htons(ETH_P_IP)) { | 
|  | /* | 
|  | *	v6 mapped | 
|  | */ | 
|  |  | 
|  | newsk = tcp_v4_syn_recv_sock(sk, skb, req, dst); | 
|  |  | 
|  | if (newsk == NULL) | 
|  | return NULL; | 
|  |  | 
|  | newtcp6sk = (struct tcp6_sock *)newsk; | 
|  | inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; | 
|  |  | 
|  | newinet = inet_sk(newsk); | 
|  | newnp = inet6_sk(newsk); | 
|  | newtp = tcp_sk(newsk); | 
|  |  | 
|  | memcpy(newnp, np, sizeof(struct ipv6_pinfo)); | 
|  |  | 
|  | ipv6_addr_set(&newnp->daddr, 0, 0, htonl(0x0000FFFF), | 
|  | newinet->daddr); | 
|  |  | 
|  | ipv6_addr_set(&newnp->saddr, 0, 0, htonl(0x0000FFFF), | 
|  | newinet->saddr); | 
|  |  | 
|  | ipv6_addr_copy(&newnp->rcv_saddr, &newnp->saddr); | 
|  |  | 
|  | inet_csk(newsk)->icsk_af_ops = &ipv6_mapped; | 
|  | newsk->sk_backlog_rcv = tcp_v4_do_rcv; | 
|  | newnp->pktoptions  = NULL; | 
|  | newnp->opt	   = NULL; | 
|  | newnp->mcast_oif   = inet6_iif(skb); | 
|  | newnp->mcast_hops  = skb->nh.ipv6h->hop_limit; | 
|  |  | 
|  | /* | 
|  | * No need to charge this sock to the relevant IPv6 refcnt debug socks count | 
|  | * here, tcp_create_openreq_child now does this for us, see the comment in | 
|  | * that function for the gory details. -acme | 
|  | */ | 
|  |  | 
|  | /* It is tricky place. Until this moment IPv4 tcp | 
|  | worked with IPv6 icsk.icsk_af_ops. | 
|  | Sync it now. | 
|  | */ | 
|  | tcp_sync_mss(newsk, inet_csk(newsk)->icsk_pmtu_cookie); | 
|  |  | 
|  | return newsk; | 
|  | } | 
|  |  | 
|  | opt = np->opt; | 
|  |  | 
|  | if (sk_acceptq_is_full(sk)) | 
|  | goto out_overflow; | 
|  |  | 
|  | if (np->rxopt.bits.osrcrt == 2 && | 
|  | opt == NULL && treq->pktopts) { | 
|  | struct inet6_skb_parm *rxopt = IP6CB(treq->pktopts); | 
|  | if (rxopt->srcrt) | 
|  | opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr *)(treq->pktopts->nh.raw + rxopt->srcrt)); | 
|  | } | 
|  |  | 
|  | if (dst == NULL) { | 
|  | struct in6_addr *final_p = NULL, final; | 
|  | struct flowi fl; | 
|  |  | 
|  | memset(&fl, 0, sizeof(fl)); | 
|  | fl.proto = IPPROTO_TCP; | 
|  | ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr); | 
|  | if (opt && opt->srcrt) { | 
|  | struct rt0_hdr *rt0 = (struct rt0_hdr *) opt->srcrt; | 
|  | ipv6_addr_copy(&final, &fl.fl6_dst); | 
|  | ipv6_addr_copy(&fl.fl6_dst, rt0->addr); | 
|  | final_p = &final; | 
|  | } | 
|  | ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr); | 
|  | fl.oif = sk->sk_bound_dev_if; | 
|  | fl.fl_ip_dport = inet_rsk(req)->rmt_port; | 
|  | fl.fl_ip_sport = inet_sk(sk)->sport; | 
|  |  | 
|  | if (ip6_dst_lookup(sk, &dst, &fl)) | 
|  | goto out; | 
|  |  | 
|  | if (final_p) | 
|  | ipv6_addr_copy(&fl.fl6_dst, final_p); | 
|  |  | 
|  | if ((xfrm_lookup(&dst, &fl, sk, 0)) < 0) | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | newsk = tcp_create_openreq_child(sk, req, skb); | 
|  | if (newsk == NULL) | 
|  | goto out; | 
|  |  | 
|  | /* | 
|  | * No need to charge this sock to the relevant IPv6 refcnt debug socks | 
|  | * count here, tcp_create_openreq_child now does this for us, see the | 
|  | * comment in that function for the gory details. -acme | 
|  | */ | 
|  |  | 
|  | ip6_dst_store(newsk, dst, NULL); | 
|  | newsk->sk_route_caps = dst->dev->features & | 
|  | ~(NETIF_F_IP_CSUM | NETIF_F_TSO); | 
|  |  | 
|  | newtcp6sk = (struct tcp6_sock *)newsk; | 
|  | inet_sk(newsk)->pinet6 = &newtcp6sk->inet6; | 
|  |  | 
|  | newtp = tcp_sk(newsk); | 
|  | newinet = inet_sk(newsk); | 
|  | newnp = inet6_sk(newsk); | 
|  |  | 
|  | memcpy(newnp, np, sizeof(struct ipv6_pinfo)); | 
|  |  | 
|  | ipv6_addr_copy(&newnp->daddr, &treq->rmt_addr); | 
|  | ipv6_addr_copy(&newnp->saddr, &treq->loc_addr); | 
|  | ipv6_addr_copy(&newnp->rcv_saddr, &treq->loc_addr); | 
|  | newsk->sk_bound_dev_if = treq->iif; | 
|  |  | 
|  | /* Now IPv6 options... | 
|  |  | 
|  | First: no IPv4 options. | 
|  | */ | 
|  | newinet->opt = NULL; | 
|  |  | 
|  | /* Clone RX bits */ | 
|  | newnp->rxopt.all = np->rxopt.all; | 
|  |  | 
|  | /* Clone pktoptions received with SYN */ | 
|  | newnp->pktoptions = NULL; | 
|  | if (treq->pktopts != NULL) { | 
|  | newnp->pktoptions = skb_clone(treq->pktopts, GFP_ATOMIC); | 
|  | kfree_skb(treq->pktopts); | 
|  | treq->pktopts = NULL; | 
|  | if (newnp->pktoptions) | 
|  | skb_set_owner_r(newnp->pktoptions, newsk); | 
|  | } | 
|  | newnp->opt	  = NULL; | 
|  | newnp->mcast_oif  = inet6_iif(skb); | 
|  | newnp->mcast_hops = skb->nh.ipv6h->hop_limit; | 
|  |  | 
|  | /* Clone native IPv6 options from listening socket (if any) | 
|  |  | 
|  | Yes, keeping reference count would be much more clever, | 
|  | but we make one more one thing there: reattach optmem | 
|  | to newsk. | 
|  | */ | 
|  | if (opt) { | 
|  | newnp->opt = ipv6_dup_options(newsk, opt); | 
|  | if (opt != np->opt) | 
|  | sock_kfree_s(sk, opt, opt->tot_len); | 
|  | } | 
|  |  | 
|  | inet_csk(newsk)->icsk_ext_hdr_len = 0; | 
|  | if (newnp->opt) | 
|  | inet_csk(newsk)->icsk_ext_hdr_len = (newnp->opt->opt_nflen + | 
|  | newnp->opt->opt_flen); | 
|  |  | 
|  | tcp_sync_mss(newsk, dst_mtu(dst)); | 
|  | newtp->advmss = dst_metric(dst, RTAX_ADVMSS); | 
|  | tcp_initialize_rcv_mss(newsk); | 
|  |  | 
|  | newinet->daddr = newinet->saddr = newinet->rcv_saddr = LOOPBACK4_IPV6; | 
|  |  | 
|  | __inet6_hash(&tcp_hashinfo, newsk); | 
|  | inet_inherit_port(&tcp_hashinfo, sk, newsk); | 
|  |  | 
|  | return newsk; | 
|  |  | 
|  | out_overflow: | 
|  | NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS); | 
|  | out: | 
|  | NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS); | 
|  | if (opt && opt != np->opt) | 
|  | sock_kfree_s(sk, opt, opt->tot_len); | 
|  | dst_release(dst); | 
|  | return NULL; | 
|  | } | 
|  |  | 
|  | static int tcp_v6_checksum_init(struct sk_buff *skb) | 
|  | { | 
|  | if (skb->ip_summed == CHECKSUM_HW) { | 
|  | if (!tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr, | 
|  | &skb->nh.ipv6h->daddr,skb->csum)) { | 
|  | skb->ip_summed = CHECKSUM_UNNECESSARY; | 
|  | return 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | skb->csum = ~tcp_v6_check(skb->h.th,skb->len,&skb->nh.ipv6h->saddr, | 
|  | &skb->nh.ipv6h->daddr, 0); | 
|  |  | 
|  | if (skb->len <= 76) { | 
|  | return __skb_checksum_complete(skb); | 
|  | } | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | /* The socket must have it's spinlock held when we get | 
|  | * here. | 
|  | * | 
|  | * We have a potential double-lock case here, so even when | 
|  | * doing backlog processing we use the BH locking scheme. | 
|  | * This is because we cannot sleep with the original spinlock | 
|  | * held. | 
|  | */ | 
|  | static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb) | 
|  | { | 
|  | struct ipv6_pinfo *np = inet6_sk(sk); | 
|  | struct tcp_sock *tp; | 
|  | struct sk_buff *opt_skb = NULL; | 
|  |  | 
|  | /* Imagine: socket is IPv6. IPv4 packet arrives, | 
|  | goes to IPv4 receive handler and backlogged. | 
|  | From backlog it always goes here. Kerboom... | 
|  | Fortunately, tcp_rcv_established and rcv_established | 
|  | handle them correctly, but it is not case with | 
|  | tcp_v6_hnd_req and tcp_v6_send_reset().   --ANK | 
|  | */ | 
|  |  | 
|  | if (skb->protocol == htons(ETH_P_IP)) | 
|  | return tcp_v4_do_rcv(sk, skb); | 
|  |  | 
|  | if (sk_filter(sk, skb, 0)) | 
|  | goto discard; | 
|  |  | 
|  | /* | 
|  | *	socket locking is here for SMP purposes as backlog rcv | 
|  | *	is currently called with bh processing disabled. | 
|  | */ | 
|  |  | 
|  | /* Do Stevens' IPV6_PKTOPTIONS. | 
|  |  | 
|  | Yes, guys, it is the only place in our code, where we | 
|  | may make it not affecting IPv4. | 
|  | The rest of code is protocol independent, | 
|  | and I do not like idea to uglify IPv4. | 
|  |  | 
|  | Actually, all the idea behind IPV6_PKTOPTIONS | 
|  | looks not very well thought. For now we latch | 
|  | options, received in the last packet, enqueued | 
|  | by tcp. Feel free to propose better solution. | 
|  | --ANK (980728) | 
|  | */ | 
|  | if (np->rxopt.all) | 
|  | opt_skb = skb_clone(skb, GFP_ATOMIC); | 
|  |  | 
|  | if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */ | 
|  | TCP_CHECK_TIMER(sk); | 
|  | if (tcp_rcv_established(sk, skb, skb->h.th, skb->len)) | 
|  | goto reset; | 
|  | TCP_CHECK_TIMER(sk); | 
|  | if (opt_skb) | 
|  | goto ipv6_pktoptions; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | if (skb->len < (skb->h.th->doff<<2) || tcp_checksum_complete(skb)) | 
|  | goto csum_err; | 
|  |  | 
|  | if (sk->sk_state == TCP_LISTEN) { | 
|  | struct sock *nsk = tcp_v6_hnd_req(sk, skb); | 
|  | if (!nsk) | 
|  | goto discard; | 
|  |  | 
|  | /* | 
|  | * Queue it on the new socket if the new socket is active, | 
|  | * otherwise we just shortcircuit this and continue with | 
|  | * the new socket.. | 
|  | */ | 
|  | if(nsk != sk) { | 
|  | if (tcp_child_process(sk, nsk, skb)) | 
|  | goto reset; | 
|  | if (opt_skb) | 
|  | __kfree_skb(opt_skb); | 
|  | return 0; | 
|  | } | 
|  | } | 
|  |  | 
|  | TCP_CHECK_TIMER(sk); | 
|  | if (tcp_rcv_state_process(sk, skb, skb->h.th, skb->len)) | 
|  | goto reset; | 
|  | TCP_CHECK_TIMER(sk); | 
|  | if (opt_skb) | 
|  | goto ipv6_pktoptions; | 
|  | return 0; | 
|  |  | 
|  | reset: | 
|  | tcp_v6_send_reset(skb); | 
|  | discard: | 
|  | if (opt_skb) | 
|  | __kfree_skb(opt_skb); | 
|  | kfree_skb(skb); | 
|  | return 0; | 
|  | csum_err: | 
|  | TCP_INC_STATS_BH(TCP_MIB_INERRS); | 
|  | goto discard; | 
|  |  | 
|  |  | 
|  | ipv6_pktoptions: | 
|  | /* Do you ask, what is it? | 
|  |  | 
|  | 1. skb was enqueued by tcp. | 
|  | 2. skb is added to tail of read queue, rather than out of order. | 
|  | 3. socket is not in passive state. | 
|  | 4. Finally, it really contains options, which user wants to receive. | 
|  | */ | 
|  | tp = tcp_sk(sk); | 
|  | if (TCP_SKB_CB(opt_skb)->end_seq == tp->rcv_nxt && | 
|  | !((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))) { | 
|  | if (np->rxopt.bits.rxinfo || np->rxopt.bits.rxoinfo) | 
|  | np->mcast_oif = inet6_iif(opt_skb); | 
|  | if (np->rxopt.bits.rxhlim || np->rxopt.bits.rxohlim) | 
|  | np->mcast_hops = opt_skb->nh.ipv6h->hop_limit; | 
|  | if (ipv6_opt_accepted(sk, opt_skb)) { | 
|  | skb_set_owner_r(opt_skb, sk); | 
|  | opt_skb = xchg(&np->pktoptions, opt_skb); | 
|  | } else { | 
|  | __kfree_skb(opt_skb); | 
|  | opt_skb = xchg(&np->pktoptions, NULL); | 
|  | } | 
|  | } | 
|  |  | 
|  | if (opt_skb) | 
|  | kfree_skb(opt_skb); | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int tcp_v6_rcv(struct sk_buff **pskb) | 
|  | { | 
|  | struct sk_buff *skb = *pskb; | 
|  | struct tcphdr *th; | 
|  | struct sock *sk; | 
|  | int ret; | 
|  |  | 
|  | if (skb->pkt_type != PACKET_HOST) | 
|  | goto discard_it; | 
|  |  | 
|  | /* | 
|  | *	Count it even if it's bad. | 
|  | */ | 
|  | TCP_INC_STATS_BH(TCP_MIB_INSEGS); | 
|  |  | 
|  | if (!pskb_may_pull(skb, sizeof(struct tcphdr))) | 
|  | goto discard_it; | 
|  |  | 
|  | th = skb->h.th; | 
|  |  | 
|  | if (th->doff < sizeof(struct tcphdr)/4) | 
|  | goto bad_packet; | 
|  | if (!pskb_may_pull(skb, th->doff*4)) | 
|  | goto discard_it; | 
|  |  | 
|  | if ((skb->ip_summed != CHECKSUM_UNNECESSARY && | 
|  | tcp_v6_checksum_init(skb))) | 
|  | goto bad_packet; | 
|  |  | 
|  | th = skb->h.th; | 
|  | TCP_SKB_CB(skb)->seq = ntohl(th->seq); | 
|  | TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin + | 
|  | skb->len - th->doff*4); | 
|  | TCP_SKB_CB(skb)->ack_seq = ntohl(th->ack_seq); | 
|  | TCP_SKB_CB(skb)->when = 0; | 
|  | TCP_SKB_CB(skb)->flags = ipv6_get_dsfield(skb->nh.ipv6h); | 
|  | TCP_SKB_CB(skb)->sacked = 0; | 
|  |  | 
|  | sk = __inet6_lookup(&tcp_hashinfo, &skb->nh.ipv6h->saddr, th->source, | 
|  | &skb->nh.ipv6h->daddr, ntohs(th->dest), | 
|  | inet6_iif(skb)); | 
|  |  | 
|  | if (!sk) | 
|  | goto no_tcp_socket; | 
|  |  | 
|  | process: | 
|  | if (sk->sk_state == TCP_TIME_WAIT) | 
|  | goto do_time_wait; | 
|  |  | 
|  | if (!xfrm6_policy_check(sk, XFRM_POLICY_IN, skb)) | 
|  | goto discard_and_relse; | 
|  |  | 
|  | if (sk_filter(sk, skb, 0)) | 
|  | goto discard_and_relse; | 
|  |  | 
|  | skb->dev = NULL; | 
|  |  | 
|  | bh_lock_sock(sk); | 
|  | ret = 0; | 
|  | if (!sock_owned_by_user(sk)) { | 
|  | if (!tcp_prequeue(sk, skb)) | 
|  | ret = tcp_v6_do_rcv(sk, skb); | 
|  | } else | 
|  | sk_add_backlog(sk, skb); | 
|  | bh_unlock_sock(sk); | 
|  |  | 
|  | sock_put(sk); | 
|  | return ret ? -1 : 0; | 
|  |  | 
|  | no_tcp_socket: | 
|  | if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) | 
|  | goto discard_it; | 
|  |  | 
|  | if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) { | 
|  | bad_packet: | 
|  | TCP_INC_STATS_BH(TCP_MIB_INERRS); | 
|  | } else { | 
|  | tcp_v6_send_reset(skb); | 
|  | } | 
|  |  | 
|  | discard_it: | 
|  |  | 
|  | /* | 
|  | *	Discard frame | 
|  | */ | 
|  |  | 
|  | kfree_skb(skb); | 
|  | return 0; | 
|  |  | 
|  | discard_and_relse: | 
|  | sock_put(sk); | 
|  | goto discard_it; | 
|  |  | 
|  | do_time_wait: | 
|  | if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { | 
|  | inet_twsk_put((struct inet_timewait_sock *)sk); | 
|  | goto discard_it; | 
|  | } | 
|  |  | 
|  | if (skb->len < (th->doff<<2) || tcp_checksum_complete(skb)) { | 
|  | TCP_INC_STATS_BH(TCP_MIB_INERRS); | 
|  | inet_twsk_put((struct inet_timewait_sock *)sk); | 
|  | goto discard_it; | 
|  | } | 
|  |  | 
|  | switch (tcp_timewait_state_process((struct inet_timewait_sock *)sk, | 
|  | skb, th)) { | 
|  | case TCP_TW_SYN: | 
|  | { | 
|  | struct sock *sk2; | 
|  |  | 
|  | sk2 = inet6_lookup_listener(&tcp_hashinfo, | 
|  | &skb->nh.ipv6h->daddr, | 
|  | ntohs(th->dest), inet6_iif(skb)); | 
|  | if (sk2 != NULL) { | 
|  | struct inet_timewait_sock *tw = inet_twsk(sk); | 
|  | inet_twsk_deschedule(tw, &tcp_death_row); | 
|  | inet_twsk_put(tw); | 
|  | sk = sk2; | 
|  | goto process; | 
|  | } | 
|  | /* Fall through to ACK */ | 
|  | } | 
|  | case TCP_TW_ACK: | 
|  | tcp_v6_timewait_ack(sk, skb); | 
|  | break; | 
|  | case TCP_TW_RST: | 
|  | goto no_tcp_socket; | 
|  | case TCP_TW_SUCCESS:; | 
|  | } | 
|  | goto discard_it; | 
|  | } | 
|  |  | 
|  | static int tcp_v6_remember_stamp(struct sock *sk) | 
|  | { | 
|  | /* Alas, not yet... */ | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static struct inet_connection_sock_af_ops ipv6_specific = { | 
|  | .queue_xmit	=	inet6_csk_xmit, | 
|  | .send_check	=	tcp_v6_send_check, | 
|  | .rebuild_header	=	inet6_sk_rebuild_header, | 
|  | .conn_request	=	tcp_v6_conn_request, | 
|  | .syn_recv_sock	=	tcp_v6_syn_recv_sock, | 
|  | .remember_stamp	=	tcp_v6_remember_stamp, | 
|  | .net_header_len	=	sizeof(struct ipv6hdr), | 
|  |  | 
|  | .setsockopt	=	ipv6_setsockopt, | 
|  | .getsockopt	=	ipv6_getsockopt, | 
|  | .addr2sockaddr	=	inet6_csk_addr2sockaddr, | 
|  | .sockaddr_len	=	sizeof(struct sockaddr_in6) | 
|  | }; | 
|  |  | 
|  | /* | 
|  | *	TCP over IPv4 via INET6 API | 
|  | */ | 
|  |  | 
|  | static struct inet_connection_sock_af_ops ipv6_mapped = { | 
|  | .queue_xmit	=	ip_queue_xmit, | 
|  | .send_check	=	tcp_v4_send_check, | 
|  | .rebuild_header	=	inet_sk_rebuild_header, | 
|  | .conn_request	=	tcp_v6_conn_request, | 
|  | .syn_recv_sock	=	tcp_v6_syn_recv_sock, | 
|  | .remember_stamp	=	tcp_v4_remember_stamp, | 
|  | .net_header_len	=	sizeof(struct iphdr), | 
|  |  | 
|  | .setsockopt	=	ipv6_setsockopt, | 
|  | .getsockopt	=	ipv6_getsockopt, | 
|  | .addr2sockaddr	=	inet6_csk_addr2sockaddr, | 
|  | .sockaddr_len	=	sizeof(struct sockaddr_in6) | 
|  | }; | 
|  |  | 
|  |  | 
|  |  | 
|  | /* NOTE: A lot of things set to zero explicitly by call to | 
|  | *       sk_alloc() so need not be done here. | 
|  | */ | 
|  | static int tcp_v6_init_sock(struct sock *sk) | 
|  | { | 
|  | struct inet_connection_sock *icsk = inet_csk(sk); | 
|  | struct tcp_sock *tp = tcp_sk(sk); | 
|  |  | 
|  | skb_queue_head_init(&tp->out_of_order_queue); | 
|  | tcp_init_xmit_timers(sk); | 
|  | tcp_prequeue_init(tp); | 
|  |  | 
|  | icsk->icsk_rto = TCP_TIMEOUT_INIT; | 
|  | tp->mdev = TCP_TIMEOUT_INIT; | 
|  |  | 
|  | /* So many TCP implementations out there (incorrectly) count the | 
|  | * initial SYN frame in their delayed-ACK and congestion control | 
|  | * algorithms that we must have the following bandaid to talk | 
|  | * efficiently to them.  -DaveM | 
|  | */ | 
|  | tp->snd_cwnd = 2; | 
|  |  | 
|  | /* See draft-stevens-tcpca-spec-01 for discussion of the | 
|  | * initialization of these values. | 
|  | */ | 
|  | tp->snd_ssthresh = 0x7fffffff; | 
|  | tp->snd_cwnd_clamp = ~0; | 
|  | tp->mss_cache = 536; | 
|  |  | 
|  | tp->reordering = sysctl_tcp_reordering; | 
|  |  | 
|  | sk->sk_state = TCP_CLOSE; | 
|  |  | 
|  | icsk->icsk_af_ops = &ipv6_specific; | 
|  | icsk->icsk_ca_ops = &tcp_init_congestion_ops; | 
|  | icsk->icsk_sync_mss = tcp_sync_mss; | 
|  | sk->sk_write_space = sk_stream_write_space; | 
|  | sock_set_flag(sk, SOCK_USE_WRITE_QUEUE); | 
|  |  | 
|  | sk->sk_sndbuf = sysctl_tcp_wmem[1]; | 
|  | sk->sk_rcvbuf = sysctl_tcp_rmem[1]; | 
|  |  | 
|  | atomic_inc(&tcp_sockets_allocated); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int tcp_v6_destroy_sock(struct sock *sk) | 
|  | { | 
|  | tcp_v4_destroy_sock(sk); | 
|  | return inet6_destroy_sock(sk); | 
|  | } | 
|  |  | 
|  | /* Proc filesystem TCPv6 sock list dumping. */ | 
|  | static void get_openreq6(struct seq_file *seq, | 
|  | struct sock *sk, struct request_sock *req, int i, int uid) | 
|  | { | 
|  | int ttd = req->expires - jiffies; | 
|  | struct in6_addr *src = &inet6_rsk(req)->loc_addr; | 
|  | struct in6_addr *dest = &inet6_rsk(req)->rmt_addr; | 
|  |  | 
|  | if (ttd < 0) | 
|  | ttd = 0; | 
|  |  | 
|  | seq_printf(seq, | 
|  | "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " | 
|  | "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n", | 
|  | i, | 
|  | src->s6_addr32[0], src->s6_addr32[1], | 
|  | src->s6_addr32[2], src->s6_addr32[3], | 
|  | ntohs(inet_sk(sk)->sport), | 
|  | dest->s6_addr32[0], dest->s6_addr32[1], | 
|  | dest->s6_addr32[2], dest->s6_addr32[3], | 
|  | ntohs(inet_rsk(req)->rmt_port), | 
|  | TCP_SYN_RECV, | 
|  | 0,0, /* could print option size, but that is af dependent. */ | 
|  | 1,   /* timers active (only the expire timer) */ | 
|  | jiffies_to_clock_t(ttd), | 
|  | req->retrans, | 
|  | uid, | 
|  | 0,  /* non standard timer */ | 
|  | 0, /* open_requests have no inode */ | 
|  | 0, req); | 
|  | } | 
|  |  | 
|  | static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i) | 
|  | { | 
|  | struct in6_addr *dest, *src; | 
|  | __u16 destp, srcp; | 
|  | int timer_active; | 
|  | unsigned long timer_expires; | 
|  | struct inet_sock *inet = inet_sk(sp); | 
|  | struct tcp_sock *tp = tcp_sk(sp); | 
|  | const struct inet_connection_sock *icsk = inet_csk(sp); | 
|  | struct ipv6_pinfo *np = inet6_sk(sp); | 
|  |  | 
|  | dest  = &np->daddr; | 
|  | src   = &np->rcv_saddr; | 
|  | destp = ntohs(inet->dport); | 
|  | srcp  = ntohs(inet->sport); | 
|  |  | 
|  | if (icsk->icsk_pending == ICSK_TIME_RETRANS) { | 
|  | timer_active	= 1; | 
|  | timer_expires	= icsk->icsk_timeout; | 
|  | } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) { | 
|  | timer_active	= 4; | 
|  | timer_expires	= icsk->icsk_timeout; | 
|  | } else if (timer_pending(&sp->sk_timer)) { | 
|  | timer_active	= 2; | 
|  | timer_expires	= sp->sk_timer.expires; | 
|  | } else { | 
|  | timer_active	= 0; | 
|  | timer_expires = jiffies; | 
|  | } | 
|  |  | 
|  | seq_printf(seq, | 
|  | "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " | 
|  | "%02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p %u %u %u %u %d\n", | 
|  | i, | 
|  | src->s6_addr32[0], src->s6_addr32[1], | 
|  | src->s6_addr32[2], src->s6_addr32[3], srcp, | 
|  | dest->s6_addr32[0], dest->s6_addr32[1], | 
|  | dest->s6_addr32[2], dest->s6_addr32[3], destp, | 
|  | sp->sk_state, | 
|  | tp->write_seq-tp->snd_una, tp->rcv_nxt-tp->copied_seq, | 
|  | timer_active, | 
|  | jiffies_to_clock_t(timer_expires - jiffies), | 
|  | icsk->icsk_retransmits, | 
|  | sock_i_uid(sp), | 
|  | icsk->icsk_probes_out, | 
|  | sock_i_ino(sp), | 
|  | atomic_read(&sp->sk_refcnt), sp, | 
|  | icsk->icsk_rto, | 
|  | icsk->icsk_ack.ato, | 
|  | (icsk->icsk_ack.quick << 1 ) | icsk->icsk_ack.pingpong, | 
|  | tp->snd_cwnd, tp->snd_ssthresh>=0xFFFF?-1:tp->snd_ssthresh | 
|  | ); | 
|  | } | 
|  |  | 
|  | static void get_timewait6_sock(struct seq_file *seq, | 
|  | struct inet_timewait_sock *tw, int i) | 
|  | { | 
|  | struct in6_addr *dest, *src; | 
|  | __u16 destp, srcp; | 
|  | struct inet6_timewait_sock *tw6 = inet6_twsk((struct sock *)tw); | 
|  | int ttd = tw->tw_ttd - jiffies; | 
|  |  | 
|  | if (ttd < 0) | 
|  | ttd = 0; | 
|  |  | 
|  | dest = &tw6->tw_v6_daddr; | 
|  | src  = &tw6->tw_v6_rcv_saddr; | 
|  | destp = ntohs(tw->tw_dport); | 
|  | srcp  = ntohs(tw->tw_sport); | 
|  |  | 
|  | seq_printf(seq, | 
|  | "%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X " | 
|  | "%02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %p\n", | 
|  | i, | 
|  | src->s6_addr32[0], src->s6_addr32[1], | 
|  | src->s6_addr32[2], src->s6_addr32[3], srcp, | 
|  | dest->s6_addr32[0], dest->s6_addr32[1], | 
|  | dest->s6_addr32[2], dest->s6_addr32[3], destp, | 
|  | tw->tw_substate, 0, 0, | 
|  | 3, jiffies_to_clock_t(ttd), 0, 0, 0, 0, | 
|  | atomic_read(&tw->tw_refcnt), tw); | 
|  | } | 
|  |  | 
|  | #ifdef CONFIG_PROC_FS | 
|  | static int tcp6_seq_show(struct seq_file *seq, void *v) | 
|  | { | 
|  | struct tcp_iter_state *st; | 
|  |  | 
|  | if (v == SEQ_START_TOKEN) { | 
|  | seq_puts(seq, | 
|  | "  sl  " | 
|  | "local_address                         " | 
|  | "remote_address                        " | 
|  | "st tx_queue rx_queue tr tm->when retrnsmt" | 
|  | "   uid  timeout inode\n"); | 
|  | goto out; | 
|  | } | 
|  | st = seq->private; | 
|  |  | 
|  | switch (st->state) { | 
|  | case TCP_SEQ_STATE_LISTENING: | 
|  | case TCP_SEQ_STATE_ESTABLISHED: | 
|  | get_tcp6_sock(seq, v, st->num); | 
|  | break; | 
|  | case TCP_SEQ_STATE_OPENREQ: | 
|  | get_openreq6(seq, st->syn_wait_sk, v, st->num, st->uid); | 
|  | break; | 
|  | case TCP_SEQ_STATE_TIME_WAIT: | 
|  | get_timewait6_sock(seq, v, st->num); | 
|  | break; | 
|  | } | 
|  | out: | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static struct file_operations tcp6_seq_fops; | 
|  | static struct tcp_seq_afinfo tcp6_seq_afinfo = { | 
|  | .owner		= THIS_MODULE, | 
|  | .name		= "tcp6", | 
|  | .family		= AF_INET6, | 
|  | .seq_show	= tcp6_seq_show, | 
|  | .seq_fops	= &tcp6_seq_fops, | 
|  | }; | 
|  |  | 
|  | int __init tcp6_proc_init(void) | 
|  | { | 
|  | return tcp_proc_register(&tcp6_seq_afinfo); | 
|  | } | 
|  |  | 
|  | void tcp6_proc_exit(void) | 
|  | { | 
|  | tcp_proc_unregister(&tcp6_seq_afinfo); | 
|  | } | 
|  | #endif | 
|  |  | 
|  | struct proto tcpv6_prot = { | 
|  | .name			= "TCPv6", | 
|  | .owner			= THIS_MODULE, | 
|  | .close			= tcp_close, | 
|  | .connect		= tcp_v6_connect, | 
|  | .disconnect		= tcp_disconnect, | 
|  | .accept			= inet_csk_accept, | 
|  | .ioctl			= tcp_ioctl, | 
|  | .init			= tcp_v6_init_sock, | 
|  | .destroy		= tcp_v6_destroy_sock, | 
|  | .shutdown		= tcp_shutdown, | 
|  | .setsockopt		= tcp_setsockopt, | 
|  | .getsockopt		= tcp_getsockopt, | 
|  | .sendmsg		= tcp_sendmsg, | 
|  | .recvmsg		= tcp_recvmsg, | 
|  | .backlog_rcv		= tcp_v6_do_rcv, | 
|  | .hash			= tcp_v6_hash, | 
|  | .unhash			= tcp_unhash, | 
|  | .get_port		= tcp_v6_get_port, | 
|  | .enter_memory_pressure	= tcp_enter_memory_pressure, | 
|  | .sockets_allocated	= &tcp_sockets_allocated, | 
|  | .memory_allocated	= &tcp_memory_allocated, | 
|  | .memory_pressure	= &tcp_memory_pressure, | 
|  | .orphan_count		= &tcp_orphan_count, | 
|  | .sysctl_mem		= sysctl_tcp_mem, | 
|  | .sysctl_wmem		= sysctl_tcp_wmem, | 
|  | .sysctl_rmem		= sysctl_tcp_rmem, | 
|  | .max_header		= MAX_TCP_HEADER, | 
|  | .obj_size		= sizeof(struct tcp6_sock), | 
|  | .twsk_prot		= &tcp6_timewait_sock_ops, | 
|  | .rsk_prot		= &tcp6_request_sock_ops, | 
|  | }; | 
|  |  | 
|  | static struct inet6_protocol tcpv6_protocol = { | 
|  | .handler	=	tcp_v6_rcv, | 
|  | .err_handler	=	tcp_v6_err, | 
|  | .flags		=	INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL, | 
|  | }; | 
|  |  | 
|  | static struct inet_protosw tcpv6_protosw = { | 
|  | .type		=	SOCK_STREAM, | 
|  | .protocol	=	IPPROTO_TCP, | 
|  | .prot		=	&tcpv6_prot, | 
|  | .ops		=	&inet6_stream_ops, | 
|  | .capability	=	-1, | 
|  | .no_check	=	0, | 
|  | .flags		=	INET_PROTOSW_PERMANENT | | 
|  | INET_PROTOSW_ICSK, | 
|  | }; | 
|  |  | 
|  | void __init tcpv6_init(void) | 
|  | { | 
|  | int err; | 
|  |  | 
|  | /* register inet6 protocol */ | 
|  | if (inet6_add_protocol(&tcpv6_protocol, IPPROTO_TCP) < 0) | 
|  | printk(KERN_ERR "tcpv6_init: Could not register protocol\n"); | 
|  | inet6_register_protosw(&tcpv6_protosw); | 
|  |  | 
|  | err = sock_create_kern(PF_INET6, SOCK_RAW, IPPROTO_TCP, &tcp6_socket); | 
|  | if (err < 0) | 
|  | panic("Failed to create the TCPv6 control socket.\n"); | 
|  | tcp6_socket->sk->sk_allocation = GFP_ATOMIC; | 
|  |  | 
|  | /* Unhash it so that IP input processing does not even | 
|  | * see it, we do not wish this socket to see incoming | 
|  | * packets. | 
|  | */ | 
|  | tcp6_socket->sk->sk_prot->unhash(tcp6_socket->sk); | 
|  | } |