1658 lines
41 KiB
C
1658 lines
41 KiB
C
/*
|
|
* TCP over IPv6
|
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* Linux INET6 implementation
|
|
*
|
|
* Authors:
|
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* Pedro Roque <roque@di.fc.ul.pt>
|
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*
|
|
* $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
|
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* linux/net/ipv4/tcp_output.c
|
|
*
|
|
* Fixes:
|
|
* Hideaki YOSHIFUJI : sin6_scope_id support
|
|
* YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
|
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* Alexey Kuznetsov allow both IPv4 and IPv6 sockets to bind
|
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* a single port at the same time.
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* YOSHIFUJI Hideaki @USAGI: convert /proc/net/tcp6 to seq_file.
|
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*
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* This program is free software; you can redistribute it and/or
|
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* modify it under the terms of the GNU General Public License
|
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
|
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*/
|
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|
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#include <linux/module.h>
|
|
#include <linux/errno.h>
|
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#include <linux/types.h>
|
|
#include <linux/socket.h>
|
|
#include <linux/sockios.h>
|
|
#include <linux/net.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/in.h>
|
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#include <linux/in6.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/init.h>
|
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#include <linux/jhash.h>
|
|
#include <linux/ipsec.h>
|
|
#include <linux/times.h>
|
|
|
|
#include <linux/ipv6.h>
|
|
#include <linux/icmpv6.h>
|
|
#include <linux/random.h>
|
|
|
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#include <net/tcp.h>
|
|
#include <net/ndisc.h>
|
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#include <net/inet6_hashtables.h>
|
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#include <net/inet6_connection_sock.h>
|
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#include <net/ipv6.h>
|
|
#include <net/transp_v6.h>
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|
#include <net/addrconf.h>
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|
#include <net/ip6_route.h>
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|
#include <net/ip6_checksum.h>
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|
#include <net/inet_ecn.h>
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|
#include <net/protocol.h>
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|
#include <net/xfrm.h>
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|
#include <net/addrconf.h>
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|
#include <net/snmp.h>
|
|
#include <net/dsfield.h>
|
|
#include <net/timewait_sock.h>
|
|
|
|
#include <asm/uaccess.h>
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|
|
|
#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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|
|
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/* Socket used for sending RSTs and ACKs */
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static struct socket *tcp6_socket;
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|
|
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static void tcp_v6_send_reset(struct sk_buff *skb);
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static void tcp_v6_reqsk_send_ack(struct sk_buff *skb, struct request_sock *req);
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static void tcp_v6_send_check(struct sock *sk, int len,
|
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struct sk_buff *skb);
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|
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static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
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|
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static struct inet_connection_sock_af_ops ipv6_mapped;
|
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static struct inet_connection_sock_af_ops ipv6_specific;
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|
|
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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();
|
|
}
|
|
}
|
|
|
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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,
|
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skb->h.th->dest,
|
|
skb->h.th->source);
|
|
}
|
|
}
|
|
|
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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);
|
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struct tcp_sock *tp = tcp_sk(sk);
|
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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;
|
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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).
|
|
*/
|
|
|
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if(ipv6_addr_any(&usin->sin6_addr))
|
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usin->sin6_addr.s6_addr[15] = 0x1;
|
|
|
|
addr_type = ipv6_addr_type(&usin->sin6_addr);
|
|
|
|
if(addr_type & IPV6_ADDR_MULTICAST)
|
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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 &&
|
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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 */
|
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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;
|
|
}
|
|
|
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ipv6_addr_copy(&np->daddr, &usin->sin6_addr);
|
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np->flow_label = fl.fl6_flowlabel;
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|
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/*
|
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* TCP over IPv4
|
|
*/
|
|
|
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if (addr_type == IPV6_ADDR_MAPPED) {
|
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u32 exthdrlen = icsk->icsk_ext_hdr_len;
|
|
struct sockaddr_in sin;
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SOCK_DEBUG(sk, "connect: ipv4 mapped\n");
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|
|
if (__ipv6_only_sock(sk))
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return -ENETUNREACH;
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|
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sin.sin_family = AF_INET;
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sin.sin_port = usin->sin6_port;
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sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
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icsk->icsk_af_ops = &ipv6_mapped;
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sk->sk_backlog_rcv = tcp_v4_do_rcv;
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err = tcp_v4_connect(sk, (struct sockaddr *)&sin, sizeof(sin));
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if (err) {
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icsk->icsk_ext_hdr_len = exthdrlen;
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icsk->icsk_af_ops = &ipv6_specific;
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sk->sk_backlog_rcv = tcp_v6_do_rcv;
|
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goto failure;
|
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} else {
|
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ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000FFFF),
|
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inet->saddr);
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ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000FFFF),
|
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inet->rcv_saddr);
|
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}
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|
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return err;
|
|
}
|
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|
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if (!ipv6_addr_any(&np->rcv_saddr))
|
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saddr = &np->rcv_saddr;
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|
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fl.proto = IPPROTO_TCP;
|
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ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
|
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ipv6_addr_copy(&fl.fl6_src,
|
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(saddr ? saddr : &np->saddr));
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fl.oif = sk->sk_bound_dev_if;
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fl.fl_ip_dport = usin->sin6_port;
|
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fl.fl_ip_sport = inet->sport;
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|
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if (np->opt && np->opt->srcrt) {
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struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
|
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ipv6_addr_copy(&final, &fl.fl6_dst);
|
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ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
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final_p = &final;
|
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}
|
|
|
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security_sk_classify_flow(sk, &fl);
|
|
|
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err = ip6_dst_lookup(sk, &dst, &fl);
|
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if (err)
|
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goto failure;
|
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if (final_p)
|
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ipv6_addr_copy(&fl.fl6_dst, final_p);
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|
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if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0)
|
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goto failure;
|
|
|
|
if (saddr == NULL) {
|
|
saddr = &fl.fl6_src;
|
|
ipv6_addr_copy(&np->rcv_saddr, saddr);
|
|
}
|
|
|
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/* set the source address */
|
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ipv6_addr_copy(&np->saddr, saddr);
|
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inet->rcv_saddr = LOOPBACK4_IPV6;
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|
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sk->sk_gso_type = SKB_GSO_TCPV6;
|
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__ip6_dst_store(sk, dst, NULL, NULL);
|
|
|
|
icsk->icsk_ext_hdr_len = 0;
|
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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;
|
|
security_skb_classify_flow(skb, &fl);
|
|
|
|
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)) {
|
|
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;
|
|
security_req_classify_flow(req, &fl);
|
|
|
|
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_PARTIAL) {
|
|
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 int tcp_v6_gso_send_check(struct sk_buff *skb)
|
|
{
|
|
struct ipv6hdr *ipv6h;
|
|
struct tcphdr *th;
|
|
|
|
if (!pskb_may_pull(skb, sizeof(*th)))
|
|
return -EINVAL;
|
|
|
|
ipv6h = skb->nh.ipv6h;
|
|
th = skb->h.th;
|
|
|
|
th->check = 0;
|
|
th->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
|
|
IPPROTO_TCP, 0);
|
|
skb->csum = offsetof(struct tcphdr, check);
|
|
skb->ip_summed = CHECKSUM_PARTIAL;
|
|
return 0;
|
|
}
|
|
|
|
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;
|
|
security_skb_classify_flow(skb, &fl);
|
|
|
|
/* 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 += TCPOLEN_TSTAMP_ALIGNED;
|
|
|
|
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;
|
|
security_skb_classify_flow(skb, &fl);
|
|
|
|
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;
|
|
|
|
security_inet_conn_request(sk, skb, req);
|
|
|
|
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);
|
|
|
|
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;
|
|
security_req_classify_flow(req, &fl);
|
|
|
|
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
|
|
*/
|
|
|
|
newsk->sk_gso_type = SKB_GSO_TCPV6;
|
|
__ip6_dst_store(newsk, dst, NULL, NULL);
|
|
|
|
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_mtup_init(newsk);
|
|
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_COMPLETE) {
|
|
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))
|
|
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))
|
|
goto discard_and_relse;
|
|
|
|
skb->dev = NULL;
|
|
|
|
bh_lock_sock_nested(sk);
|
|
ret = 0;
|
|
if (!sock_owned_by_user(sk)) {
|
|
#ifdef CONFIG_NET_DMA
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
if (tp->ucopy.dma_chan)
|
|
ret = tcp_v6_do_rcv(sk, skb);
|
|
else
|
|
#endif
|
|
{
|
|
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),
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_setsockopt = compat_ipv6_setsockopt,
|
|
.compat_getsockopt = compat_ipv6_getsockopt,
|
|
#endif
|
|
};
|
|
|
|
/*
|
|
* 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),
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_setsockopt = compat_ipv6_setsockopt,
|
|
.compat_getsockopt = compat_ipv6_getsockopt,
|
|
#endif
|
|
};
|
|
|
|
/* 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,
|
|
(sp->sk_state == TCP_LISTEN) ? sp->sk_ack_backlog : (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,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_setsockopt = compat_tcp_setsockopt,
|
|
.compat_getsockopt = compat_tcp_getsockopt,
|
|
#endif
|
|
};
|
|
|
|
static struct inet6_protocol tcpv6_protocol = {
|
|
.handler = tcp_v6_rcv,
|
|
.err_handler = tcp_v6_err,
|
|
.gso_send_check = tcp_v6_gso_send_check,
|
|
.gso_segment = tcp_tso_segment,
|
|
.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)
|
|
{
|
|
/* 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);
|
|
|
|
if (inet_csk_ctl_sock_create(&tcp6_socket, PF_INET6, SOCK_RAW,
|
|
IPPROTO_TCP) < 0)
|
|
panic("Failed to create the TCPv6 control socket.\n");
|
|
}
|