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Copy pathtcp_ipv6.c
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tcp_ipv6.c
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/*
* TCP over IPv6
* Linux INET6 implementation
*
* Authors:
* Pedro Roque <[email protected]>
*
* 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/bottom_half.h>
#include <linux/module.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/slab.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/snmp.h>
#include <net/dsfield.h>
#include <net/timewait_sock.h>
#include <net/netdma.h>
#include <net/inet_common.h>
#include <net/secure_seq.h>
#include <asm/uaccess.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/crypto.h>
#include <linux/scatterlist.h>
static void tcp_v6_send_reset(struct sock *sk, struct sk_buff *skb);
static void tcp_v6_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
struct request_sock *req);
static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb);
static void __tcp_v6_send_check(struct sk_buff *skb,
const struct in6_addr *saddr,
const struct in6_addr *daddr);
static const struct inet_connection_sock_af_ops ipv6_mapped;
static const struct inet_connection_sock_af_ops ipv6_specific;
#ifdef CONFIG_TCP_MD5SIG
static const struct tcp_sock_af_ops tcp_sock_ipv6_specific;
static const struct tcp_sock_af_ops tcp_sock_ipv6_mapped_specific;
#else
static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk,
const struct in6_addr *addr)
{
return NULL;
}
#endif
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(sk, NULL);
local_bh_enable();
}
}
static __inline__ __sum16 tcp_v6_check(int len,
const struct in6_addr *saddr,
const struct in6_addr *daddr,
__wsum base)
{
return csum_ipv6_magic(saddr, daddr, len, IPPROTO_TCP, base);
}
static __u32 tcp_v6_init_sequence(struct sk_buff *skb)
{
return secure_tcpv6_sequence_number(ipv6_hdr(skb)->daddr.s6_addr32,
ipv6_hdr(skb)->saddr.s6_addr32,
tcp_hdr(skb)->dest,
tcp_hdr(skb)->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, final;
struct rt6_info *rt;
struct flowi6 fl6;
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(&fl6, 0, sizeof(fl6));
if (np->sndflow) {
fl6.flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
IP6_ECN_flow_init(fl6.flowlabel);
if (fl6.flowlabel&IPV6_FLOWLABEL_MASK) {
struct ip6_flowlabel *flowlabel;
flowlabel = fl6_sock_lookup(sk, 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 = 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;
#ifdef CONFIG_TCP_MD5SIG
tp->af_specific = &tcp_sock_ipv6_mapped_specific;
#endif
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;
#ifdef CONFIG_TCP_MD5SIG
tp->af_specific = &tcp_sock_ipv6_specific;
#endif
goto failure;
} else {
ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
&np->rcv_saddr);
}
return err;
}
if (!ipv6_addr_any(&np->rcv_saddr))
saddr = &np->rcv_saddr;
fl6.flowi6_proto = IPPROTO_TCP;
ipv6_addr_copy(&fl6.daddr, &np->daddr);
ipv6_addr_copy(&fl6.saddr,
(saddr ? saddr : &np->saddr));
fl6.flowi6_oif = sk->sk_bound_dev_if;
fl6.flowi6_mark = sk->sk_mark;
fl6.fl6_dport = usin->sin6_port;
fl6.fl6_sport = inet->inet_sport;
final_p = fl6_update_dst(&fl6, np->opt, &final);
security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
dst = ip6_dst_lookup_flow(sk, &fl6, final_p, true);
if (IS_ERR(dst)) {
err = PTR_ERR(dst);
goto failure;
}
if (saddr == NULL) {
saddr = &fl6.saddr;
ipv6_addr_copy(&np->rcv_saddr, saddr);
}
/* set the source address */
ipv6_addr_copy(&np->saddr, saddr);
inet->inet_rcv_saddr = LOOPBACK4_IPV6;
sk->sk_gso_type = SKB_GSO_TCPV6;
__ip6_dst_store(sk, dst, NULL, NULL);
rt = (struct rt6_info *) dst;
if (tcp_death_row.sysctl_tw_recycle &&
!tp->rx_opt.ts_recent_stamp &&
ipv6_addr_equal(&rt->rt6i_dst.addr, &np->daddr)) {
struct inet_peer *peer = rt6_get_peer(rt);
/*
* VJ's idea. We save last timestamp seen from
* the destination in peer table, when entering state
* TIME-WAIT * and initialize rx_opt.ts_recent from it,
* when trying new connection.
*/
if (peer) {
inet_peer_refcheck(peer);
if ((u32)get_seconds() - peer->tcp_ts_stamp <= TCP_PAWS_MSL) {
tp->rx_opt.ts_recent_stamp = peer->tcp_ts_stamp;
tp->rx_opt.ts_recent = peer->tcp_ts;
}
}
}
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->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->inet_sport,
inet->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->inet_dport = 0;
sk->sk_route_caps = 0;
return err;
}
static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
const struct ipv6hdr *hdr = (const 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;
struct net *net = dev_net(skb->dev);
sk = inet6_lookup(net, &tcp_hashinfo, &hdr->daddr,
th->dest, &hdr->saddr, th->source, skb->dev->ifindex);
if (sk == NULL) {
ICMP6_INC_STATS_BH(net, __in6_dev_get(skb->dev),
ICMP6_MIB_INERRORS);
return;
}
if (sk->sk_state == TCP_TIME_WAIT) {
inet_twsk_put(inet_twsk(sk));
return;
}
bh_lock_sock(sk);
if (sock_owned_by_user(sk))
NET_INC_STATS_BH(net, LINUX_MIB_LOCKDROPPEDICMPS);
if (sk->sk_state == TCP_CLOSE)
goto out;
if (ipv6_hdr(skb)->hop_limit < inet6_sk(sk)->min_hopcount) {
NET_INC_STATS_BH(net, LINUX_MIB_TCPMINTTLDROP);
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(net, LINUX_MIB_OUTOFWINDOWICMPS);
goto out;
}
np = inet6_sk(sk);
if (type == ICMPV6_PKT_TOOBIG) {
struct dst_entry *dst;
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 flowi6 fl6;
/* BUGGG_FUTURE: Again, it is not clear how
to handle rthdr case. Ignore this complexity
for now.
*/
memset(&fl6, 0, sizeof(fl6));
fl6.flowi6_proto = IPPROTO_TCP;
ipv6_addr_copy(&fl6.daddr, &np->daddr);
ipv6_addr_copy(&fl6.saddr, &np->saddr);
fl6.flowi6_oif = sk->sk_bound_dev_if;
fl6.flowi6_mark = sk->sk_mark;
fl6.fl6_dport = inet->inet_dport;
fl6.fl6_sport = inet->inet_sport;
security_skb_classify_flow(skb, flowi6_to_flowi(&fl6));
dst = ip6_dst_lookup_flow(sk, &fl6, NULL, false);
if (IS_ERR(dst)) {
sk->sk_err_soft = -PTR_ERR(dst);
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.
*/
WARN_ON(req->sk != NULL);
if (seq != tcp_rsk(req)->snt_isn) {
NET_INC_STATS_BH(net, 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 request_values *rvp)
{
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, final;
struct flowi6 fl6;
struct dst_entry *dst;
int err;
memset(&fl6, 0, sizeof(fl6));
fl6.flowi6_proto = IPPROTO_TCP;
ipv6_addr_copy(&fl6.daddr, &treq->rmt_addr);
ipv6_addr_copy(&fl6.saddr, &treq->loc_addr);
fl6.flowlabel = 0;
fl6.flowi6_oif = treq->iif;
fl6.flowi6_mark = sk->sk_mark;
fl6.fl6_dport = inet_rsk(req)->rmt_port;
fl6.fl6_sport = inet_rsk(req)->loc_port;
security_req_classify_flow(req, flowi6_to_flowi(&fl6));
opt = np->opt;
final_p = fl6_update_dst(&fl6, opt, &final);
dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
if (IS_ERR(dst)) {
err = PTR_ERR(dst);
dst = NULL;
goto done;
}
skb = tcp_make_synack(sk, dst, req, rvp);
err = -ENOMEM;
if (skb) {
__tcp_v6_send_check(skb, &treq->loc_addr, &treq->rmt_addr);
ipv6_addr_copy(&fl6.daddr, &treq->rmt_addr);
err = ip6_xmit(sk, skb, &fl6, opt);
err = net_xmit_eval(err);
}
done:
if (opt && opt != np->opt)
sock_kfree_s(sk, opt, opt->tot_len);
dst_release(dst);
return err;
}
static int tcp_v6_rtx_synack(struct sock *sk, struct request_sock *req,
struct request_values *rvp)
{
TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_RETRANSSEGS);
return tcp_v6_send_synack(sk, req, rvp);
}
static inline void syn_flood_warning(struct sk_buff *skb)
{
#ifdef CONFIG_SYN_COOKIES
if (sysctl_tcp_syncookies)
printk(KERN_INFO
"TCPv6: Possible SYN flooding on port %d. "
"Sending cookies.\n", ntohs(tcp_hdr(skb)->dest));
else
#endif
printk(KERN_INFO
"TCPv6: Possible SYN flooding on port %d. "
"Dropping request.\n", ntohs(tcp_hdr(skb)->dest));
}
static void tcp_v6_reqsk_destructor(struct request_sock *req)
{
kfree_skb(inet6_rsk(req)->pktopts);
}
#ifdef CONFIG_TCP_MD5SIG
static struct tcp_md5sig_key *tcp_v6_md5_do_lookup(struct sock *sk,
const struct in6_addr *addr)
{
struct tcp_sock *tp = tcp_sk(sk);
int i;
BUG_ON(tp == NULL);
if (!tp->md5sig_info || !tp->md5sig_info->entries6)
return NULL;
for (i = 0; i < tp->md5sig_info->entries6; i++) {
if (ipv6_addr_equal(&tp->md5sig_info->keys6[i].addr, addr))
return &tp->md5sig_info->keys6[i].base;
}
return NULL;
}
static struct tcp_md5sig_key *tcp_v6_md5_lookup(struct sock *sk,
struct sock *addr_sk)
{
return tcp_v6_md5_do_lookup(sk, &inet6_sk(addr_sk)->daddr);
}
static struct tcp_md5sig_key *tcp_v6_reqsk_md5_lookup(struct sock *sk,
struct request_sock *req)
{
return tcp_v6_md5_do_lookup(sk, &inet6_rsk(req)->rmt_addr);
}
static int tcp_v6_md5_do_add(struct sock *sk, const struct in6_addr *peer,
char *newkey, u8 newkeylen)
{
/* Add key to the list */
struct tcp_md5sig_key *key;
struct tcp_sock *tp = tcp_sk(sk);
struct tcp6_md5sig_key *keys;
key = tcp_v6_md5_do_lookup(sk, peer);
if (key) {
/* modify existing entry - just update that one */
kfree(key->key);
key->key = newkey;
key->keylen = newkeylen;
} else {
/* reallocate new list if current one is full. */
if (!tp->md5sig_info) {
tp->md5sig_info = kzalloc(sizeof(*tp->md5sig_info), GFP_ATOMIC);
if (!tp->md5sig_info) {
kfree(newkey);
return -ENOMEM;
}
sk_nocaps_add(sk, NETIF_F_GSO_MASK);
}
if (tp->md5sig_info->entries6 == 0 &&
tcp_alloc_md5sig_pool(sk) == NULL) {
kfree(newkey);
return -ENOMEM;
}
if (tp->md5sig_info->alloced6 == tp->md5sig_info->entries6) {
keys = kmalloc((sizeof (tp->md5sig_info->keys6[0]) *
(tp->md5sig_info->entries6 + 1)), GFP_ATOMIC);
if (!keys) {
kfree(newkey);
if (tp->md5sig_info->entries6 == 0)
tcp_free_md5sig_pool();
return -ENOMEM;
}
if (tp->md5sig_info->entries6)
memmove(keys, tp->md5sig_info->keys6,
(sizeof (tp->md5sig_info->keys6[0]) *
tp->md5sig_info->entries6));
kfree(tp->md5sig_info->keys6);
tp->md5sig_info->keys6 = keys;
tp->md5sig_info->alloced6++;
}
ipv6_addr_copy(&tp->md5sig_info->keys6[tp->md5sig_info->entries6].addr,
peer);
tp->md5sig_info->keys6[tp->md5sig_info->entries6].base.key = newkey;
tp->md5sig_info->keys6[tp->md5sig_info->entries6].base.keylen = newkeylen;
tp->md5sig_info->entries6++;
}
return 0;
}
static int tcp_v6_md5_add_func(struct sock *sk, struct sock *addr_sk,
u8 *newkey, __u8 newkeylen)
{
return tcp_v6_md5_do_add(sk, &inet6_sk(addr_sk)->daddr,
newkey, newkeylen);
}
static int tcp_v6_md5_do_del(struct sock *sk, const struct in6_addr *peer)
{
struct tcp_sock *tp = tcp_sk(sk);
int i;
for (i = 0; i < tp->md5sig_info->entries6; i++) {
if (ipv6_addr_equal(&tp->md5sig_info->keys6[i].addr, peer)) {
/* Free the key */
kfree(tp->md5sig_info->keys6[i].base.key);
tp->md5sig_info->entries6--;
if (tp->md5sig_info->entries6 == 0) {
kfree(tp->md5sig_info->keys6);
tp->md5sig_info->keys6 = NULL;
tp->md5sig_info->alloced6 = 0;
tcp_free_md5sig_pool();
} else {
/* shrink the database */
if (tp->md5sig_info->entries6 != i)
memmove(&tp->md5sig_info->keys6[i],
&tp->md5sig_info->keys6[i+1],
(tp->md5sig_info->entries6 - i)
* sizeof (tp->md5sig_info->keys6[0]));
}
return 0;
}
}
return -ENOENT;
}
static void tcp_v6_clear_md5_list (struct sock *sk)
{
struct tcp_sock *tp = tcp_sk(sk);
int i;
if (tp->md5sig_info->entries6) {
for (i = 0; i < tp->md5sig_info->entries6; i++)
kfree(tp->md5sig_info->keys6[i].base.key);
tp->md5sig_info->entries6 = 0;
tcp_free_md5sig_pool();
}
kfree(tp->md5sig_info->keys6);
tp->md5sig_info->keys6 = NULL;
tp->md5sig_info->alloced6 = 0;
if (tp->md5sig_info->entries4) {
for (i = 0; i < tp->md5sig_info->entries4; i++)
kfree(tp->md5sig_info->keys4[i].base.key);
tp->md5sig_info->entries4 = 0;
tcp_free_md5sig_pool();
}
kfree(tp->md5sig_info->keys4);
tp->md5sig_info->keys4 = NULL;
tp->md5sig_info->alloced4 = 0;
}
static int tcp_v6_parse_md5_keys (struct sock *sk, char __user *optval,
int optlen)
{
struct tcp_md5sig cmd;
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&cmd.tcpm_addr;
u8 *newkey;
if (optlen < sizeof(cmd))
return -EINVAL;
if (copy_from_user(&cmd, optval, sizeof(cmd)))
return -EFAULT;
if (sin6->sin6_family != AF_INET6)
return -EINVAL;
if (!cmd.tcpm_keylen) {
if (!tcp_sk(sk)->md5sig_info)
return -ENOENT;
if (ipv6_addr_v4mapped(&sin6->sin6_addr))
return tcp_v4_md5_do_del(sk, sin6->sin6_addr.s6_addr32[3]);
return tcp_v6_md5_do_del(sk, &sin6->sin6_addr);
}
if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN)
return -EINVAL;
if (!tcp_sk(sk)->md5sig_info) {
struct tcp_sock *tp = tcp_sk(sk);
struct tcp_md5sig_info *p;
p = kzalloc(sizeof(struct tcp_md5sig_info), GFP_KERNEL);
if (!p)
return -ENOMEM;
tp->md5sig_info = p;
sk_nocaps_add(sk, NETIF_F_GSO_MASK);
}
newkey = kmemdup(cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL);
if (!newkey)
return -ENOMEM;
if (ipv6_addr_v4mapped(&sin6->sin6_addr)) {
return tcp_v4_md5_do_add(sk, sin6->sin6_addr.s6_addr32[3],
newkey, cmd.tcpm_keylen);
}
return tcp_v6_md5_do_add(sk, &sin6->sin6_addr, newkey, cmd.tcpm_keylen);
}
static int tcp_v6_md5_hash_pseudoheader(struct tcp_md5sig_pool *hp,
const struct in6_addr *daddr,
const struct in6_addr *saddr, int nbytes)
{
struct tcp6_pseudohdr *bp;
struct scatterlist sg;
bp = &hp->md5_blk.ip6;
/* 1. TCP pseudo-header (RFC2460) */
ipv6_addr_copy(&bp->saddr, saddr);
ipv6_addr_copy(&bp->daddr, daddr);
bp->protocol = cpu_to_be32(IPPROTO_TCP);
bp->len = cpu_to_be32(nbytes);
sg_init_one(&sg, bp, sizeof(*bp));
return crypto_hash_update(&hp->md5_desc, &sg, sizeof(*bp));
}
static int tcp_v6_md5_hash_hdr(char *md5_hash, struct tcp_md5sig_key *key,
const struct in6_addr *daddr, struct in6_addr *saddr,
struct tcphdr *th)
{
struct tcp_md5sig_pool *hp;
struct hash_desc *desc;
hp = tcp_get_md5sig_pool();
if (!hp)
goto clear_hash_noput;
desc = &hp->md5_desc;
if (crypto_hash_init(desc))
goto clear_hash;
if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, th->doff << 2))
goto clear_hash;
if (tcp_md5_hash_header(hp, th))
goto clear_hash;
if (tcp_md5_hash_key(hp, key))
goto clear_hash;
if (crypto_hash_final(desc, md5_hash))
goto clear_hash;
tcp_put_md5sig_pool();
return 0;
clear_hash:
tcp_put_md5sig_pool();
clear_hash_noput:
memset(md5_hash, 0, 16);
return 1;
}
static int tcp_v6_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key,
struct sock *sk, struct request_sock *req,
struct sk_buff *skb)
{
const struct in6_addr *saddr, *daddr;
struct tcp_md5sig_pool *hp;
struct hash_desc *desc;
struct tcphdr *th = tcp_hdr(skb);
if (sk) {
saddr = &inet6_sk(sk)->saddr;
daddr = &inet6_sk(sk)->daddr;
} else if (req) {
saddr = &inet6_rsk(req)->loc_addr;
daddr = &inet6_rsk(req)->rmt_addr;
} else {
const struct ipv6hdr *ip6h = ipv6_hdr(skb);
saddr = &ip6h->saddr;
daddr = &ip6h->daddr;
}
hp = tcp_get_md5sig_pool();
if (!hp)
goto clear_hash_noput;
desc = &hp->md5_desc;
if (crypto_hash_init(desc))
goto clear_hash;
if (tcp_v6_md5_hash_pseudoheader(hp, daddr, saddr, skb->len))
goto clear_hash;
if (tcp_md5_hash_header(hp, th))
goto clear_hash;
if (tcp_md5_hash_skb_data(hp, skb, th->doff << 2))
goto clear_hash;
if (tcp_md5_hash_key(hp, key))
goto clear_hash;
if (crypto_hash_final(desc, md5_hash))
goto clear_hash;
tcp_put_md5sig_pool();
return 0;
clear_hash:
tcp_put_md5sig_pool();
clear_hash_noput:
memset(md5_hash, 0, 16);
return 1;
}
static int tcp_v6_inbound_md5_hash (struct sock *sk, struct sk_buff *skb)
{
__u8 *hash_location = NULL;
struct tcp_md5sig_key *hash_expected;
const struct ipv6hdr *ip6h = ipv6_hdr(skb);
struct tcphdr *th = tcp_hdr(skb);
int genhash;
u8 newhash[16];
hash_expected = tcp_v6_md5_do_lookup(sk, &ip6h->saddr);
hash_location = tcp_parse_md5sig_option(th);
/* We've parsed the options - do we have a hash? */
if (!hash_expected && !hash_location)
return 0;
if (hash_expected && !hash_location) {
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
return 1;
}
if (!hash_expected && hash_location) {
NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
return 1;
}
/* check the signature */
genhash = tcp_v6_md5_hash_skb(newhash,
hash_expected,
NULL, NULL, skb);
if (genhash || memcmp(hash_location, newhash, 16) != 0) {
if (net_ratelimit()) {
printk(KERN_INFO "MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u\n",
genhash ? "failed" : "mismatch",
&ip6h->saddr, ntohs(th->source),
&ip6h->daddr, ntohs(th->dest));
}
return 1;
}
return 0;
}
#endif
struct request_sock_ops tcp6_request_sock_ops __read_mostly = {
.family = AF_INET6,
.obj_size = sizeof(struct tcp6_request_sock),
.rtx_syn_ack = tcp_v6_rtx_synack,
.send_ack = tcp_v6_reqsk_send_ack,
.destructor = tcp_v6_reqsk_destructor,
.send_reset = tcp_v6_send_reset,
.syn_ack_timeout = tcp_syn_ack_timeout,
};
#ifdef CONFIG_TCP_MD5SIG
static const struct tcp_request_sock_ops tcp_request_sock_ipv6_ops = {
.md5_lookup = tcp_v6_reqsk_md5_lookup,
.calc_md5_hash = tcp_v6_md5_hash_skb,
};
#endif
static void __tcp_v6_send_check(struct sk_buff *skb,
const struct in6_addr *saddr, const struct in6_addr *daddr)
{
struct tcphdr *th = tcp_hdr(skb);
if (skb->ip_summed == CHECKSUM_PARTIAL) {
th->check = ~tcp_v6_check(skb->len, saddr, daddr, 0);
skb->csum_start = skb_transport_header(skb) - skb->head;
skb->csum_offset = offsetof(struct tcphdr, check);
} else {
th->check = tcp_v6_check(skb->len, saddr, daddr,
csum_partial(th, th->doff << 2,
skb->csum));
}
}
static void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb)
{
struct ipv6_pinfo *np = inet6_sk(sk);
__tcp_v6_send_check(skb, &np->saddr, &np->daddr);
}
static int tcp_v6_gso_send_check(struct sk_buff *skb)
{
const struct ipv6hdr *ipv6h;
struct tcphdr *th;
if (!pskb_may_pull(skb, sizeof(*th)))
return -EINVAL;
ipv6h = ipv6_hdr(skb);
th = tcp_hdr(skb);
th->check = 0;
skb->ip_summed = CHECKSUM_PARTIAL;
__tcp_v6_send_check(skb, &ipv6h->saddr, &ipv6h->daddr);
return 0;
}
static struct sk_buff **tcp6_gro_receive(struct sk_buff **head,
struct sk_buff *skb)
{
const struct ipv6hdr *iph = skb_gro_network_header(skb);
switch (skb->ip_summed) {
case CHECKSUM_COMPLETE:
if (!tcp_v6_check(skb_gro_len(skb), &iph->saddr, &iph->daddr,
skb->csum)) {
skb->ip_summed = CHECKSUM_UNNECESSARY;
break;
}
/* fall through */
case CHECKSUM_NONE:
NAPI_GRO_CB(skb)->flush = 1;
return NULL;
}
return tcp_gro_receive(head, skb);
}
static int tcp6_gro_complete(struct sk_buff *skb)
{
const struct ipv6hdr *iph = ipv6_hdr(skb);
struct tcphdr *th = tcp_hdr(skb);
th->check = ~tcp_v6_check(skb->len - skb_transport_offset(skb),
&iph->saddr, &iph->daddr, 0);
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6;
return tcp_gro_complete(skb);
}
static void tcp_v6_send_response(struct sk_buff *skb, u32 seq, u32 ack, u32 win,
u32 ts, struct tcp_md5sig_key *key, int rst)
{
struct tcphdr *th = tcp_hdr(skb), *t1;
struct sk_buff *buff;
struct flowi6 fl6;
struct net *net = dev_net(skb_dst(skb)->dev);