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![David S. Miller](/assets/img/avatar_default.png)
Honestly all the conflicts were simple overlapping changes, nothing really interesting to report. Signed-off-by: David S. Miller <davem@davemloft.net>
2738 lines
71 KiB
C
2738 lines
71 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* INET An implementation of the TCP/IP protocol suite for the LINUX
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* operating system. INET is implemented using the BSD Socket
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* interface as the means of communication with the user level.
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*
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* Implementation of the Transmission Control Protocol(TCP).
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*
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* IPv4 specific functions
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*
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* code split from:
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* linux/ipv4/tcp.c
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* linux/ipv4/tcp_input.c
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* linux/ipv4/tcp_output.c
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*
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* See tcp.c for author information
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*/
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/*
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* Changes:
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* David S. Miller : New socket lookup architecture.
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* This code is dedicated to John Dyson.
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* David S. Miller : Change semantics of established hash,
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* half is devoted to TIME_WAIT sockets
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* and the rest go in the other half.
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* Andi Kleen : Add support for syncookies and fixed
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* some bugs: ip options weren't passed to
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* the TCP layer, missed a check for an
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* ACK bit.
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* Andi Kleen : Implemented fast path mtu discovery.
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* Fixed many serious bugs in the
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* request_sock handling and moved
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* most of it into the af independent code.
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* Added tail drop and some other bugfixes.
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* Added new listen semantics.
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* Mike McLagan : Routing by source
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* Juan Jose Ciarlante: ip_dynaddr bits
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* Andi Kleen: various fixes.
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* Vitaly E. Lavrov : Transparent proxy revived after year
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* coma.
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* Andi Kleen : Fix new listen.
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* Andi Kleen : Fix accept error reporting.
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* 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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*/
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#define pr_fmt(fmt) "TCP: " fmt
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#include <linux/bottom_half.h>
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#include <linux/types.h>
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#include <linux/fcntl.h>
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#include <linux/module.h>
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#include <linux/random.h>
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#include <linux/cache.h>
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#include <linux/jhash.h>
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#include <linux/init.h>
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#include <linux/times.h>
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#include <linux/slab.h>
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#include <net/net_namespace.h>
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#include <net/icmp.h>
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#include <net/inet_hashtables.h>
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#include <net/tcp.h>
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#include <net/transp_v6.h>
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#include <net/ipv6.h>
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#include <net/inet_common.h>
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#include <net/timewait_sock.h>
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#include <net/xfrm.h>
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#include <net/secure_seq.h>
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#include <net/busy_poll.h>
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#include <linux/inet.h>
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#include <linux/ipv6.h>
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#include <linux/stddef.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
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#include <linux/inetdevice.h>
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#include <crypto/hash.h>
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#include <linux/scatterlist.h>
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#include <trace/events/tcp.h>
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#ifdef CONFIG_TCP_MD5SIG
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static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key,
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__be32 daddr, __be32 saddr, const struct tcphdr *th);
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#endif
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struct inet_hashinfo tcp_hashinfo;
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EXPORT_SYMBOL(tcp_hashinfo);
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static u32 tcp_v4_init_seq(const struct sk_buff *skb)
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{
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return secure_tcp_seq(ip_hdr(skb)->daddr,
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ip_hdr(skb)->saddr,
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tcp_hdr(skb)->dest,
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tcp_hdr(skb)->source);
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}
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static u32 tcp_v4_init_ts_off(const struct net *net, const struct sk_buff *skb)
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{
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return secure_tcp_ts_off(net, ip_hdr(skb)->daddr, ip_hdr(skb)->saddr);
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}
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int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp)
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{
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const struct inet_timewait_sock *tw = inet_twsk(sktw);
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const struct tcp_timewait_sock *tcptw = tcp_twsk(sktw);
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struct tcp_sock *tp = tcp_sk(sk);
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int reuse = sock_net(sk)->ipv4.sysctl_tcp_tw_reuse;
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if (reuse == 2) {
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/* Still does not detect *everything* that goes through
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* lo, since we require a loopback src or dst address
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* or direct binding to 'lo' interface.
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*/
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bool loopback = false;
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if (tw->tw_bound_dev_if == LOOPBACK_IFINDEX)
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loopback = true;
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#if IS_ENABLED(CONFIG_IPV6)
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if (tw->tw_family == AF_INET6) {
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if (ipv6_addr_loopback(&tw->tw_v6_daddr) ||
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(ipv6_addr_v4mapped(&tw->tw_v6_daddr) &&
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(tw->tw_v6_daddr.s6_addr[12] == 127)) ||
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ipv6_addr_loopback(&tw->tw_v6_rcv_saddr) ||
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(ipv6_addr_v4mapped(&tw->tw_v6_rcv_saddr) &&
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(tw->tw_v6_rcv_saddr.s6_addr[12] == 127)))
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loopback = true;
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} else
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#endif
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{
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if (ipv4_is_loopback(tw->tw_daddr) ||
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ipv4_is_loopback(tw->tw_rcv_saddr))
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loopback = true;
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}
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if (!loopback)
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reuse = 0;
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}
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/* With PAWS, it is safe from the viewpoint
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of data integrity. Even without PAWS it is safe provided sequence
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spaces do not overlap i.e. at data rates <= 80Mbit/sec.
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Actually, the idea is close to VJ's one, only timestamp cache is
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held not per host, but per port pair and TW bucket is used as state
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holder.
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If TW bucket has been already destroyed we fall back to VJ's scheme
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and use initial timestamp retrieved from peer table.
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*/
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if (tcptw->tw_ts_recent_stamp &&
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(!twp || (reuse && time_after32(ktime_get_seconds(),
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tcptw->tw_ts_recent_stamp)))) {
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/* In case of repair and re-using TIME-WAIT sockets we still
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* want to be sure that it is safe as above but honor the
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* sequence numbers and time stamps set as part of the repair
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* process.
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*
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* Without this check re-using a TIME-WAIT socket with TCP
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* repair would accumulate a -1 on the repair assigned
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* sequence number. The first time it is reused the sequence
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* is -1, the second time -2, etc. This fixes that issue
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* without appearing to create any others.
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*/
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if (likely(!tp->repair)) {
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tp->write_seq = tcptw->tw_snd_nxt + 65535 + 2;
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if (tp->write_seq == 0)
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tp->write_seq = 1;
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tp->rx_opt.ts_recent = tcptw->tw_ts_recent;
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tp->rx_opt.ts_recent_stamp = tcptw->tw_ts_recent_stamp;
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}
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sock_hold(sktw);
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return 1;
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}
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return 0;
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}
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EXPORT_SYMBOL_GPL(tcp_twsk_unique);
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static int tcp_v4_pre_connect(struct sock *sk, struct sockaddr *uaddr,
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int addr_len)
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{
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/* This check is replicated from tcp_v4_connect() and intended to
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* prevent BPF program called below from accessing bytes that are out
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* of the bound specified by user in addr_len.
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*/
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if (addr_len < sizeof(struct sockaddr_in))
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return -EINVAL;
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sock_owned_by_me(sk);
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return BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr);
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}
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/* This will initiate an outgoing connection. */
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int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
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{
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struct sockaddr_in *usin = (struct sockaddr_in *)uaddr;
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struct inet_sock *inet = inet_sk(sk);
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struct tcp_sock *tp = tcp_sk(sk);
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__be16 orig_sport, orig_dport;
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__be32 daddr, nexthop;
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struct flowi4 *fl4;
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struct rtable *rt;
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int err;
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struct ip_options_rcu *inet_opt;
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struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row;
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if (addr_len < sizeof(struct sockaddr_in))
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return -EINVAL;
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if (usin->sin_family != AF_INET)
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return -EAFNOSUPPORT;
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nexthop = daddr = usin->sin_addr.s_addr;
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inet_opt = rcu_dereference_protected(inet->inet_opt,
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lockdep_sock_is_held(sk));
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if (inet_opt && inet_opt->opt.srr) {
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if (!daddr)
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return -EINVAL;
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nexthop = inet_opt->opt.faddr;
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}
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orig_sport = inet->inet_sport;
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orig_dport = usin->sin_port;
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fl4 = &inet->cork.fl.u.ip4;
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rt = ip_route_connect(fl4, nexthop, inet->inet_saddr,
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RT_CONN_FLAGS(sk), sk->sk_bound_dev_if,
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IPPROTO_TCP,
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orig_sport, orig_dport, sk);
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if (IS_ERR(rt)) {
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err = PTR_ERR(rt);
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if (err == -ENETUNREACH)
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IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
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return err;
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}
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if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) {
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ip_rt_put(rt);
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return -ENETUNREACH;
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}
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if (!inet_opt || !inet_opt->opt.srr)
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daddr = fl4->daddr;
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if (!inet->inet_saddr)
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inet->inet_saddr = fl4->saddr;
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sk_rcv_saddr_set(sk, inet->inet_saddr);
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if (tp->rx_opt.ts_recent_stamp && inet->inet_daddr != daddr) {
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/* Reset inherited state */
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tp->rx_opt.ts_recent = 0;
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tp->rx_opt.ts_recent_stamp = 0;
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if (likely(!tp->repair))
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tp->write_seq = 0;
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}
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inet->inet_dport = usin->sin_port;
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sk_daddr_set(sk, daddr);
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inet_csk(sk)->icsk_ext_hdr_len = 0;
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if (inet_opt)
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inet_csk(sk)->icsk_ext_hdr_len = inet_opt->opt.optlen;
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tp->rx_opt.mss_clamp = TCP_MSS_DEFAULT;
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/* Socket identity is still unknown (sport may be zero).
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* However we set state to SYN-SENT and not releasing socket
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* lock select source port, enter ourselves into the hash tables and
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* complete initialization after this.
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*/
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tcp_set_state(sk, TCP_SYN_SENT);
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err = inet_hash_connect(tcp_death_row, sk);
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if (err)
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goto failure;
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sk_set_txhash(sk);
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rt = ip_route_newports(fl4, rt, orig_sport, orig_dport,
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inet->inet_sport, inet->inet_dport, sk);
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if (IS_ERR(rt)) {
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err = PTR_ERR(rt);
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rt = NULL;
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goto failure;
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}
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/* OK, now commit destination to socket. */
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sk->sk_gso_type = SKB_GSO_TCPV4;
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sk_setup_caps(sk, &rt->dst);
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rt = NULL;
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if (likely(!tp->repair)) {
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if (!tp->write_seq)
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tp->write_seq = secure_tcp_seq(inet->inet_saddr,
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inet->inet_daddr,
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inet->inet_sport,
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usin->sin_port);
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tp->tsoffset = secure_tcp_ts_off(sock_net(sk),
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inet->inet_saddr,
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inet->inet_daddr);
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}
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inet->inet_id = tp->write_seq ^ jiffies;
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if (tcp_fastopen_defer_connect(sk, &err))
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return err;
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if (err)
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goto failure;
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err = tcp_connect(sk);
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if (err)
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goto failure;
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return 0;
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failure:
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/*
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* This unhashes the socket and releases the local port,
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* if necessary.
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*/
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tcp_set_state(sk, TCP_CLOSE);
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ip_rt_put(rt);
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sk->sk_route_caps = 0;
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inet->inet_dport = 0;
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return err;
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}
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EXPORT_SYMBOL(tcp_v4_connect);
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|
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/*
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* This routine reacts to ICMP_FRAG_NEEDED mtu indications as defined in RFC1191.
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* It can be called through tcp_release_cb() if socket was owned by user
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* at the time tcp_v4_err() was called to handle ICMP message.
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*/
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void tcp_v4_mtu_reduced(struct sock *sk)
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{
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struct inet_sock *inet = inet_sk(sk);
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struct dst_entry *dst;
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u32 mtu;
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if ((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))
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return;
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mtu = tcp_sk(sk)->mtu_info;
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dst = inet_csk_update_pmtu(sk, mtu);
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if (!dst)
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return;
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|
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/* Something is about to be wrong... Remember soft error
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* for the case, if this connection will not able to recover.
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*/
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if (mtu < dst_mtu(dst) && ip_dont_fragment(sk, dst))
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sk->sk_err_soft = EMSGSIZE;
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mtu = dst_mtu(dst);
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|
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if (inet->pmtudisc != IP_PMTUDISC_DONT &&
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ip_sk_accept_pmtu(sk) &&
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inet_csk(sk)->icsk_pmtu_cookie > mtu) {
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tcp_sync_mss(sk, mtu);
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|
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/* Resend the TCP packet because it's
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* clear that the old packet has been
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* dropped. This is the new "fast" path mtu
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* discovery.
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*/
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tcp_simple_retransmit(sk);
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} /* else let the usual retransmit timer handle it */
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}
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EXPORT_SYMBOL(tcp_v4_mtu_reduced);
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|
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static void do_redirect(struct sk_buff *skb, struct sock *sk)
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{
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struct dst_entry *dst = __sk_dst_check(sk, 0);
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|
|
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if (dst)
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dst->ops->redirect(dst, sk, skb);
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}
|
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|
|
|
|
/* handle ICMP messages on TCP_NEW_SYN_RECV request sockets */
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void tcp_req_err(struct sock *sk, u32 seq, bool abort)
|
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{
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struct request_sock *req = inet_reqsk(sk);
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struct net *net = sock_net(sk);
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|
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/* ICMPs are not backlogged, hence we cannot get
|
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* an established socket here.
|
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*/
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if (seq != tcp_rsk(req)->snt_isn) {
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__NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS);
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} else if (abort) {
|
|
/*
|
|
* Still in SYN_RECV, just remove it silently.
|
|
* There is no good way to pass the error to the newly
|
|
* created socket, and POSIX does not want network
|
|
* errors returned from accept().
|
|
*/
|
|
inet_csk_reqsk_queue_drop(req->rsk_listener, req);
|
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tcp_listendrop(req->rsk_listener);
|
|
}
|
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reqsk_put(req);
|
|
}
|
|
EXPORT_SYMBOL(tcp_req_err);
|
|
|
|
/*
|
|
* This routine is called by the ICMP module when it gets some
|
|
* sort of error condition. If err < 0 then the socket should
|
|
* be closed and the error returned to the user. If err > 0
|
|
* it's just the icmp type << 8 | icmp code. After adjustment
|
|
* header points to the first 8 bytes of the tcp header. We need
|
|
* to find the appropriate port.
|
|
*
|
|
* The locking strategy used here is very "optimistic". When
|
|
* someone else accesses the socket the ICMP is just dropped
|
|
* and for some paths there is no check at all.
|
|
* A more general error queue to queue errors for later handling
|
|
* is probably better.
|
|
*
|
|
*/
|
|
|
|
int tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
|
|
{
|
|
const struct iphdr *iph = (const struct iphdr *)icmp_skb->data;
|
|
struct tcphdr *th = (struct tcphdr *)(icmp_skb->data + (iph->ihl << 2));
|
|
struct inet_connection_sock *icsk;
|
|
struct tcp_sock *tp;
|
|
struct inet_sock *inet;
|
|
const int type = icmp_hdr(icmp_skb)->type;
|
|
const int code = icmp_hdr(icmp_skb)->code;
|
|
struct sock *sk;
|
|
struct sk_buff *skb;
|
|
struct request_sock *fastopen;
|
|
u32 seq, snd_una;
|
|
s32 remaining;
|
|
u32 delta_us;
|
|
int err;
|
|
struct net *net = dev_net(icmp_skb->dev);
|
|
|
|
sk = __inet_lookup_established(net, &tcp_hashinfo, iph->daddr,
|
|
th->dest, iph->saddr, ntohs(th->source),
|
|
inet_iif(icmp_skb), 0);
|
|
if (!sk) {
|
|
__ICMP_INC_STATS(net, ICMP_MIB_INERRORS);
|
|
return -ENOENT;
|
|
}
|
|
if (sk->sk_state == TCP_TIME_WAIT) {
|
|
inet_twsk_put(inet_twsk(sk));
|
|
return 0;
|
|
}
|
|
seq = ntohl(th->seq);
|
|
if (sk->sk_state == TCP_NEW_SYN_RECV) {
|
|
tcp_req_err(sk, seq, type == ICMP_PARAMETERPROB ||
|
|
type == ICMP_TIME_EXCEEDED ||
|
|
(type == ICMP_DEST_UNREACH &&
|
|
(code == ICMP_NET_UNREACH ||
|
|
code == ICMP_HOST_UNREACH)));
|
|
return 0;
|
|
}
|
|
|
|
bh_lock_sock(sk);
|
|
/* If too many ICMPs get dropped on busy
|
|
* servers this needs to be solved differently.
|
|
* We do take care of PMTU discovery (RFC1191) special case :
|
|
* we can receive locally generated ICMP messages while socket is held.
|
|
*/
|
|
if (sock_owned_by_user(sk)) {
|
|
if (!(type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED))
|
|
__NET_INC_STATS(net, LINUX_MIB_LOCKDROPPEDICMPS);
|
|
}
|
|
if (sk->sk_state == TCP_CLOSE)
|
|
goto out;
|
|
|
|
if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) {
|
|
__NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP);
|
|
goto out;
|
|
}
|
|
|
|
icsk = inet_csk(sk);
|
|
tp = tcp_sk(sk);
|
|
/* XXX (TFO) - tp->snd_una should be ISN (tcp_create_openreq_child() */
|
|
fastopen = tp->fastopen_rsk;
|
|
snd_una = fastopen ? tcp_rsk(fastopen)->snt_isn : tp->snd_una;
|
|
if (sk->sk_state != TCP_LISTEN &&
|
|
!between(seq, snd_una, tp->snd_nxt)) {
|
|
__NET_INC_STATS(net, LINUX_MIB_OUTOFWINDOWICMPS);
|
|
goto out;
|
|
}
|
|
|
|
switch (type) {
|
|
case ICMP_REDIRECT:
|
|
if (!sock_owned_by_user(sk))
|
|
do_redirect(icmp_skb, sk);
|
|
goto out;
|
|
case ICMP_SOURCE_QUENCH:
|
|
/* Just silently ignore these. */
|
|
goto out;
|
|
case ICMP_PARAMETERPROB:
|
|
err = EPROTO;
|
|
break;
|
|
case ICMP_DEST_UNREACH:
|
|
if (code > NR_ICMP_UNREACH)
|
|
goto out;
|
|
|
|
if (code == ICMP_FRAG_NEEDED) { /* PMTU discovery (RFC1191) */
|
|
/* We are not interested in TCP_LISTEN and open_requests
|
|
* (SYN-ACKs send out by Linux are always <576bytes so
|
|
* they should go through unfragmented).
|
|
*/
|
|
if (sk->sk_state == TCP_LISTEN)
|
|
goto out;
|
|
|
|
tp->mtu_info = info;
|
|
if (!sock_owned_by_user(sk)) {
|
|
tcp_v4_mtu_reduced(sk);
|
|
} else {
|
|
if (!test_and_set_bit(TCP_MTU_REDUCED_DEFERRED, &sk->sk_tsq_flags))
|
|
sock_hold(sk);
|
|
}
|
|
goto out;
|
|
}
|
|
|
|
err = icmp_err_convert[code].errno;
|
|
/* check if icmp_skb allows revert of backoff
|
|
* (see draft-zimmermann-tcp-lcd) */
|
|
if (code != ICMP_NET_UNREACH && code != ICMP_HOST_UNREACH)
|
|
break;
|
|
if (seq != tp->snd_una || !icsk->icsk_retransmits ||
|
|
!icsk->icsk_backoff || fastopen)
|
|
break;
|
|
|
|
if (sock_owned_by_user(sk))
|
|
break;
|
|
|
|
skb = tcp_rtx_queue_head(sk);
|
|
if (WARN_ON_ONCE(!skb))
|
|
break;
|
|
|
|
icsk->icsk_backoff--;
|
|
icsk->icsk_rto = tp->srtt_us ? __tcp_set_rto(tp) :
|
|
TCP_TIMEOUT_INIT;
|
|
icsk->icsk_rto = inet_csk_rto_backoff(icsk, TCP_RTO_MAX);
|
|
|
|
|
|
tcp_mstamp_refresh(tp);
|
|
delta_us = (u32)(tp->tcp_mstamp - tcp_skb_timestamp_us(skb));
|
|
remaining = icsk->icsk_rto -
|
|
usecs_to_jiffies(delta_us);
|
|
|
|
if (remaining > 0) {
|
|
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
|
|
remaining, TCP_RTO_MAX);
|
|
} else {
|
|
/* RTO revert clocked out retransmission.
|
|
* Will retransmit now */
|
|
tcp_retransmit_timer(sk);
|
|
}
|
|
|
|
break;
|
|
case ICMP_TIME_EXCEEDED:
|
|
err = EHOSTUNREACH;
|
|
break;
|
|
default:
|
|
goto out;
|
|
}
|
|
|
|
switch (sk->sk_state) {
|
|
case TCP_SYN_SENT:
|
|
case TCP_SYN_RECV:
|
|
/* Only in fast or simultaneous open. If a fast open socket is
|
|
* is already accepted it is treated as a connected one below.
|
|
*/
|
|
if (fastopen && !fastopen->sk)
|
|
break;
|
|
|
|
if (!sock_owned_by_user(sk)) {
|
|
sk->sk_err = err;
|
|
|
|
sk->sk_error_report(sk);
|
|
|
|
tcp_done(sk);
|
|
} else {
|
|
sk->sk_err_soft = err;
|
|
}
|
|
goto out;
|
|
}
|
|
|
|
/* If we've already connected we will keep trying
|
|
* until we time out, or the user gives up.
|
|
*
|
|
* rfc1122 4.2.3.9 allows to consider as hard errors
|
|
* only PROTO_UNREACH and PORT_UNREACH (well, FRAG_FAILED too,
|
|
* but it is obsoleted by pmtu discovery).
|
|
*
|
|
* Note, that in modern internet, where routing is unreliable
|
|
* and in each dark corner broken firewalls sit, sending random
|
|
* errors ordered by their masters even this two messages finally lose
|
|
* their original sense (even Linux sends invalid PORT_UNREACHs)
|
|
*
|
|
* Now we are in compliance with RFCs.
|
|
* --ANK (980905)
|
|
*/
|
|
|
|
inet = inet_sk(sk);
|
|
if (!sock_owned_by_user(sk) && inet->recverr) {
|
|
sk->sk_err = err;
|
|
sk->sk_error_report(sk);
|
|
} else { /* Only an error on timeout */
|
|
sk->sk_err_soft = err;
|
|
}
|
|
|
|
out:
|
|
bh_unlock_sock(sk);
|
|
sock_put(sk);
|
|
return 0;
|
|
}
|
|
|
|
void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr)
|
|
{
|
|
struct tcphdr *th = tcp_hdr(skb);
|
|
|
|
th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0);
|
|
skb->csum_start = skb_transport_header(skb) - skb->head;
|
|
skb->csum_offset = offsetof(struct tcphdr, check);
|
|
}
|
|
|
|
/* This routine computes an IPv4 TCP checksum. */
|
|
void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
const struct inet_sock *inet = inet_sk(sk);
|
|
|
|
__tcp_v4_send_check(skb, inet->inet_saddr, inet->inet_daddr);
|
|
}
|
|
EXPORT_SYMBOL(tcp_v4_send_check);
|
|
|
|
/*
|
|
* This routine will send an RST to the other tcp.
|
|
*
|
|
* Someone asks: why I NEVER use socket parameters (TOS, TTL etc.)
|
|
* for reset.
|
|
* Answer: if a packet caused RST, it is not for a socket
|
|
* existing in our system, if it is matched to a socket,
|
|
* it is just duplicate segment or bug in other side's TCP.
|
|
* So that we build reply only basing on parameters
|
|
* arrived with segment.
|
|
* Exception: precedence violation. We do not implement it in any case.
|
|
*/
|
|
|
|
static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
const struct tcphdr *th = tcp_hdr(skb);
|
|
struct {
|
|
struct tcphdr th;
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
__be32 opt[(TCPOLEN_MD5SIG_ALIGNED >> 2)];
|
|
#endif
|
|
} rep;
|
|
struct ip_reply_arg arg;
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
struct tcp_md5sig_key *key = NULL;
|
|
const __u8 *hash_location = NULL;
|
|
unsigned char newhash[16];
|
|
int genhash;
|
|
struct sock *sk1 = NULL;
|
|
#endif
|
|
u64 transmit_time = 0;
|
|
struct sock *ctl_sk;
|
|
struct net *net;
|
|
|
|
/* Never send a reset in response to a reset. */
|
|
if (th->rst)
|
|
return;
|
|
|
|
/* If sk not NULL, it means we did a successful lookup and incoming
|
|
* route had to be correct. prequeue might have dropped our dst.
|
|
*/
|
|
if (!sk && skb_rtable(skb)->rt_type != RTN_LOCAL)
|
|
return;
|
|
|
|
/* Swap the send and the receive. */
|
|
memset(&rep, 0, sizeof(rep));
|
|
rep.th.dest = th->source;
|
|
rep.th.source = th->dest;
|
|
rep.th.doff = sizeof(struct tcphdr) / 4;
|
|
rep.th.rst = 1;
|
|
|
|
if (th->ack) {
|
|
rep.th.seq = th->ack_seq;
|
|
} else {
|
|
rep.th.ack = 1;
|
|
rep.th.ack_seq = htonl(ntohl(th->seq) + th->syn + th->fin +
|
|
skb->len - (th->doff << 2));
|
|
}
|
|
|
|
memset(&arg, 0, sizeof(arg));
|
|
arg.iov[0].iov_base = (unsigned char *)&rep;
|
|
arg.iov[0].iov_len = sizeof(rep.th);
|
|
|
|
net = sk ? sock_net(sk) : dev_net(skb_dst(skb)->dev);
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
rcu_read_lock();
|
|
hash_location = tcp_parse_md5sig_option(th);
|
|
if (sk && sk_fullsock(sk)) {
|
|
key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)
|
|
&ip_hdr(skb)->saddr, AF_INET);
|
|
} else if (hash_location) {
|
|
/*
|
|
* active side is lost. Try to find listening socket through
|
|
* source port, and then find md5 key through listening socket.
|
|
* we are not loose security here:
|
|
* Incoming packet is checked with md5 hash with finding key,
|
|
* no RST generated if md5 hash doesn't match.
|
|
*/
|
|
sk1 = __inet_lookup_listener(net, &tcp_hashinfo, NULL, 0,
|
|
ip_hdr(skb)->saddr,
|
|
th->source, ip_hdr(skb)->daddr,
|
|
ntohs(th->source), inet_iif(skb),
|
|
tcp_v4_sdif(skb));
|
|
/* don't send rst if it can't find key */
|
|
if (!sk1)
|
|
goto out;
|
|
|
|
key = tcp_md5_do_lookup(sk1, (union tcp_md5_addr *)
|
|
&ip_hdr(skb)->saddr, AF_INET);
|
|
if (!key)
|
|
goto out;
|
|
|
|
|
|
genhash = tcp_v4_md5_hash_skb(newhash, key, NULL, skb);
|
|
if (genhash || memcmp(hash_location, newhash, 16) != 0)
|
|
goto out;
|
|
|
|
}
|
|
|
|
if (key) {
|
|
rep.opt[0] = htonl((TCPOPT_NOP << 24) |
|
|
(TCPOPT_NOP << 16) |
|
|
(TCPOPT_MD5SIG << 8) |
|
|
TCPOLEN_MD5SIG);
|
|
/* Update length and the length the header thinks exists */
|
|
arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED;
|
|
rep.th.doff = arg.iov[0].iov_len / 4;
|
|
|
|
tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[1],
|
|
key, ip_hdr(skb)->saddr,
|
|
ip_hdr(skb)->daddr, &rep.th);
|
|
}
|
|
#endif
|
|
arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr,
|
|
ip_hdr(skb)->saddr, /* XXX */
|
|
arg.iov[0].iov_len, IPPROTO_TCP, 0);
|
|
arg.csumoffset = offsetof(struct tcphdr, check) / 2;
|
|
arg.flags = (sk && inet_sk_transparent(sk)) ? IP_REPLY_ARG_NOSRCCHECK : 0;
|
|
|
|
/* When socket is gone, all binding information is lost.
|
|
* routing might fail in this case. No choice here, if we choose to force
|
|
* input interface, we will misroute in case of asymmetric route.
|
|
*/
|
|
if (sk) {
|
|
arg.bound_dev_if = sk->sk_bound_dev_if;
|
|
if (sk_fullsock(sk))
|
|
trace_tcp_send_reset(sk, skb);
|
|
}
|
|
|
|
BUILD_BUG_ON(offsetof(struct sock, sk_bound_dev_if) !=
|
|
offsetof(struct inet_timewait_sock, tw_bound_dev_if));
|
|
|
|
arg.tos = ip_hdr(skb)->tos;
|
|
arg.uid = sock_net_uid(net, sk && sk_fullsock(sk) ? sk : NULL);
|
|
local_bh_disable();
|
|
ctl_sk = this_cpu_read(*net->ipv4.tcp_sk);
|
|
if (sk) {
|
|
ctl_sk->sk_mark = (sk->sk_state == TCP_TIME_WAIT) ?
|
|
inet_twsk(sk)->tw_mark : sk->sk_mark;
|
|
transmit_time = tcp_transmit_time(sk);
|
|
}
|
|
ip_send_unicast_reply(ctl_sk,
|
|
skb, &TCP_SKB_CB(skb)->header.h4.opt,
|
|
ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
|
|
&arg, arg.iov[0].iov_len,
|
|
transmit_time);
|
|
|
|
ctl_sk->sk_mark = 0;
|
|
__TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
|
|
__TCP_INC_STATS(net, TCP_MIB_OUTRSTS);
|
|
local_bh_enable();
|
|
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
out:
|
|
rcu_read_unlock();
|
|
#endif
|
|
}
|
|
|
|
/* The code following below sending ACKs in SYN-RECV and TIME-WAIT states
|
|
outside socket context is ugly, certainly. What can I do?
|
|
*/
|
|
|
|
static void tcp_v4_send_ack(const struct sock *sk,
|
|
struct sk_buff *skb, u32 seq, u32 ack,
|
|
u32 win, u32 tsval, u32 tsecr, int oif,
|
|
struct tcp_md5sig_key *key,
|
|
int reply_flags, u8 tos)
|
|
{
|
|
const struct tcphdr *th = tcp_hdr(skb);
|
|
struct {
|
|
struct tcphdr th;
|
|
__be32 opt[(TCPOLEN_TSTAMP_ALIGNED >> 2)
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
+ (TCPOLEN_MD5SIG_ALIGNED >> 2)
|
|
#endif
|
|
];
|
|
} rep;
|
|
struct net *net = sock_net(sk);
|
|
struct ip_reply_arg arg;
|
|
struct sock *ctl_sk;
|
|
u64 transmit_time;
|
|
|
|
memset(&rep.th, 0, sizeof(struct tcphdr));
|
|
memset(&arg, 0, sizeof(arg));
|
|
|
|
arg.iov[0].iov_base = (unsigned char *)&rep;
|
|
arg.iov[0].iov_len = sizeof(rep.th);
|
|
if (tsecr) {
|
|
rep.opt[0] = htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
|
|
(TCPOPT_TIMESTAMP << 8) |
|
|
TCPOLEN_TIMESTAMP);
|
|
rep.opt[1] = htonl(tsval);
|
|
rep.opt[2] = htonl(tsecr);
|
|
arg.iov[0].iov_len += TCPOLEN_TSTAMP_ALIGNED;
|
|
}
|
|
|
|
/* Swap the send and the receive. */
|
|
rep.th.dest = th->source;
|
|
rep.th.source = th->dest;
|
|
rep.th.doff = arg.iov[0].iov_len / 4;
|
|
rep.th.seq = htonl(seq);
|
|
rep.th.ack_seq = htonl(ack);
|
|
rep.th.ack = 1;
|
|
rep.th.window = htons(win);
|
|
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
if (key) {
|
|
int offset = (tsecr) ? 3 : 0;
|
|
|
|
rep.opt[offset++] = htonl((TCPOPT_NOP << 24) |
|
|
(TCPOPT_NOP << 16) |
|
|
(TCPOPT_MD5SIG << 8) |
|
|
TCPOLEN_MD5SIG);
|
|
arg.iov[0].iov_len += TCPOLEN_MD5SIG_ALIGNED;
|
|
rep.th.doff = arg.iov[0].iov_len/4;
|
|
|
|
tcp_v4_md5_hash_hdr((__u8 *) &rep.opt[offset],
|
|
key, ip_hdr(skb)->saddr,
|
|
ip_hdr(skb)->daddr, &rep.th);
|
|
}
|
|
#endif
|
|
arg.flags = reply_flags;
|
|
arg.csum = csum_tcpudp_nofold(ip_hdr(skb)->daddr,
|
|
ip_hdr(skb)->saddr, /* XXX */
|
|
arg.iov[0].iov_len, IPPROTO_TCP, 0);
|
|
arg.csumoffset = offsetof(struct tcphdr, check) / 2;
|
|
if (oif)
|
|
arg.bound_dev_if = oif;
|
|
arg.tos = tos;
|
|
arg.uid = sock_net_uid(net, sk_fullsock(sk) ? sk : NULL);
|
|
local_bh_disable();
|
|
ctl_sk = this_cpu_read(*net->ipv4.tcp_sk);
|
|
ctl_sk->sk_mark = (sk->sk_state == TCP_TIME_WAIT) ?
|
|
inet_twsk(sk)->tw_mark : sk->sk_mark;
|
|
transmit_time = tcp_transmit_time(sk);
|
|
ip_send_unicast_reply(ctl_sk,
|
|
skb, &TCP_SKB_CB(skb)->header.h4.opt,
|
|
ip_hdr(skb)->saddr, ip_hdr(skb)->daddr,
|
|
&arg, arg.iov[0].iov_len,
|
|
transmit_time);
|
|
|
|
ctl_sk->sk_mark = 0;
|
|
__TCP_INC_STATS(net, TCP_MIB_OUTSEGS);
|
|
local_bh_enable();
|
|
}
|
|
|
|
static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct inet_timewait_sock *tw = inet_twsk(sk);
|
|
struct tcp_timewait_sock *tcptw = tcp_twsk(sk);
|
|
|
|
tcp_v4_send_ack(sk, skb,
|
|
tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt,
|
|
tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale,
|
|
tcp_time_stamp_raw() + tcptw->tw_ts_offset,
|
|
tcptw->tw_ts_recent,
|
|
tw->tw_bound_dev_if,
|
|
tcp_twsk_md5_key(tcptw),
|
|
tw->tw_transparent ? IP_REPLY_ARG_NOSRCCHECK : 0,
|
|
tw->tw_tos
|
|
);
|
|
|
|
inet_twsk_put(tw);
|
|
}
|
|
|
|
static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb,
|
|
struct request_sock *req)
|
|
{
|
|
/* sk->sk_state == TCP_LISTEN -> for regular TCP_SYN_RECV
|
|
* sk->sk_state == TCP_SYN_RECV -> for Fast Open.
|
|
*/
|
|
u32 seq = (sk->sk_state == TCP_LISTEN) ? tcp_rsk(req)->snt_isn + 1 :
|
|
tcp_sk(sk)->snd_nxt;
|
|
|
|
/* RFC 7323 2.3
|
|
* The window field (SEG.WND) of every outgoing segment, with the
|
|
* exception of <SYN> segments, MUST be right-shifted by
|
|
* Rcv.Wind.Shift bits:
|
|
*/
|
|
tcp_v4_send_ack(sk, skb, seq,
|
|
tcp_rsk(req)->rcv_nxt,
|
|
req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale,
|
|
tcp_time_stamp_raw() + tcp_rsk(req)->ts_off,
|
|
req->ts_recent,
|
|
0,
|
|
tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&ip_hdr(skb)->saddr,
|
|
AF_INET),
|
|
inet_rsk(req)->no_srccheck ? IP_REPLY_ARG_NOSRCCHECK : 0,
|
|
ip_hdr(skb)->tos);
|
|
}
|
|
|
|
/*
|
|
* Send a SYN-ACK after having received a SYN.
|
|
* This still operates on a request_sock only, not on a big
|
|
* socket.
|
|
*/
|
|
static int tcp_v4_send_synack(const struct sock *sk, struct dst_entry *dst,
|
|
struct flowi *fl,
|
|
struct request_sock *req,
|
|
struct tcp_fastopen_cookie *foc,
|
|
enum tcp_synack_type synack_type)
|
|
{
|
|
const struct inet_request_sock *ireq = inet_rsk(req);
|
|
struct flowi4 fl4;
|
|
int err = -1;
|
|
struct sk_buff *skb;
|
|
|
|
/* First, grab a route. */
|
|
if (!dst && (dst = inet_csk_route_req(sk, &fl4, req)) == NULL)
|
|
return -1;
|
|
|
|
skb = tcp_make_synack(sk, dst, req, foc, synack_type);
|
|
|
|
if (skb) {
|
|
__tcp_v4_send_check(skb, ireq->ir_loc_addr, ireq->ir_rmt_addr);
|
|
|
|
rcu_read_lock();
|
|
err = ip_build_and_send_pkt(skb, sk, ireq->ir_loc_addr,
|
|
ireq->ir_rmt_addr,
|
|
rcu_dereference(ireq->ireq_opt));
|
|
rcu_read_unlock();
|
|
err = net_xmit_eval(err);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* IPv4 request_sock destructor.
|
|
*/
|
|
static void tcp_v4_reqsk_destructor(struct request_sock *req)
|
|
{
|
|
kfree(rcu_dereference_protected(inet_rsk(req)->ireq_opt, 1));
|
|
}
|
|
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
/*
|
|
* RFC2385 MD5 checksumming requires a mapping of
|
|
* IP address->MD5 Key.
|
|
* We need to maintain these in the sk structure.
|
|
*/
|
|
|
|
DEFINE_STATIC_KEY_FALSE(tcp_md5_needed);
|
|
EXPORT_SYMBOL(tcp_md5_needed);
|
|
|
|
/* Find the Key structure for an address. */
|
|
struct tcp_md5sig_key *__tcp_md5_do_lookup(const struct sock *sk,
|
|
const union tcp_md5_addr *addr,
|
|
int family)
|
|
{
|
|
const struct tcp_sock *tp = tcp_sk(sk);
|
|
struct tcp_md5sig_key *key;
|
|
const struct tcp_md5sig_info *md5sig;
|
|
__be32 mask;
|
|
struct tcp_md5sig_key *best_match = NULL;
|
|
bool match;
|
|
|
|
/* caller either holds rcu_read_lock() or socket lock */
|
|
md5sig = rcu_dereference_check(tp->md5sig_info,
|
|
lockdep_sock_is_held(sk));
|
|
if (!md5sig)
|
|
return NULL;
|
|
|
|
hlist_for_each_entry_rcu(key, &md5sig->head, node) {
|
|
if (key->family != family)
|
|
continue;
|
|
|
|
if (family == AF_INET) {
|
|
mask = inet_make_mask(key->prefixlen);
|
|
match = (key->addr.a4.s_addr & mask) ==
|
|
(addr->a4.s_addr & mask);
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
} else if (family == AF_INET6) {
|
|
match = ipv6_prefix_equal(&key->addr.a6, &addr->a6,
|
|
key->prefixlen);
|
|
#endif
|
|
} else {
|
|
match = false;
|
|
}
|
|
|
|
if (match && (!best_match ||
|
|
key->prefixlen > best_match->prefixlen))
|
|
best_match = key;
|
|
}
|
|
return best_match;
|
|
}
|
|
EXPORT_SYMBOL(__tcp_md5_do_lookup);
|
|
|
|
static struct tcp_md5sig_key *tcp_md5_do_lookup_exact(const struct sock *sk,
|
|
const union tcp_md5_addr *addr,
|
|
int family, u8 prefixlen)
|
|
{
|
|
const struct tcp_sock *tp = tcp_sk(sk);
|
|
struct tcp_md5sig_key *key;
|
|
unsigned int size = sizeof(struct in_addr);
|
|
const struct tcp_md5sig_info *md5sig;
|
|
|
|
/* caller either holds rcu_read_lock() or socket lock */
|
|
md5sig = rcu_dereference_check(tp->md5sig_info,
|
|
lockdep_sock_is_held(sk));
|
|
if (!md5sig)
|
|
return NULL;
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
if (family == AF_INET6)
|
|
size = sizeof(struct in6_addr);
|
|
#endif
|
|
hlist_for_each_entry_rcu(key, &md5sig->head, node) {
|
|
if (key->family != family)
|
|
continue;
|
|
if (!memcmp(&key->addr, addr, size) &&
|
|
key->prefixlen == prefixlen)
|
|
return key;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
struct tcp_md5sig_key *tcp_v4_md5_lookup(const struct sock *sk,
|
|
const struct sock *addr_sk)
|
|
{
|
|
const union tcp_md5_addr *addr;
|
|
|
|
addr = (const union tcp_md5_addr *)&addr_sk->sk_daddr;
|
|
return tcp_md5_do_lookup(sk, addr, AF_INET);
|
|
}
|
|
EXPORT_SYMBOL(tcp_v4_md5_lookup);
|
|
|
|
/* This can be called on a newly created socket, from other files */
|
|
int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr,
|
|
int family, u8 prefixlen, const u8 *newkey, u8 newkeylen,
|
|
gfp_t gfp)
|
|
{
|
|
/* Add Key to the list */
|
|
struct tcp_md5sig_key *key;
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
struct tcp_md5sig_info *md5sig;
|
|
|
|
key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen);
|
|
if (key) {
|
|
/* Pre-existing entry - just update that one. */
|
|
memcpy(key->key, newkey, newkeylen);
|
|
key->keylen = newkeylen;
|
|
return 0;
|
|
}
|
|
|
|
md5sig = rcu_dereference_protected(tp->md5sig_info,
|
|
lockdep_sock_is_held(sk));
|
|
if (!md5sig) {
|
|
md5sig = kmalloc(sizeof(*md5sig), gfp);
|
|
if (!md5sig)
|
|
return -ENOMEM;
|
|
|
|
sk_nocaps_add(sk, NETIF_F_GSO_MASK);
|
|
INIT_HLIST_HEAD(&md5sig->head);
|
|
rcu_assign_pointer(tp->md5sig_info, md5sig);
|
|
}
|
|
|
|
key = sock_kmalloc(sk, sizeof(*key), gfp);
|
|
if (!key)
|
|
return -ENOMEM;
|
|
if (!tcp_alloc_md5sig_pool()) {
|
|
sock_kfree_s(sk, key, sizeof(*key));
|
|
return -ENOMEM;
|
|
}
|
|
|
|
memcpy(key->key, newkey, newkeylen);
|
|
key->keylen = newkeylen;
|
|
key->family = family;
|
|
key->prefixlen = prefixlen;
|
|
memcpy(&key->addr, addr,
|
|
(family == AF_INET6) ? sizeof(struct in6_addr) :
|
|
sizeof(struct in_addr));
|
|
hlist_add_head_rcu(&key->node, &md5sig->head);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(tcp_md5_do_add);
|
|
|
|
int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, int family,
|
|
u8 prefixlen)
|
|
{
|
|
struct tcp_md5sig_key *key;
|
|
|
|
key = tcp_md5_do_lookup_exact(sk, addr, family, prefixlen);
|
|
if (!key)
|
|
return -ENOENT;
|
|
hlist_del_rcu(&key->node);
|
|
atomic_sub(sizeof(*key), &sk->sk_omem_alloc);
|
|
kfree_rcu(key, rcu);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(tcp_md5_do_del);
|
|
|
|
static void tcp_clear_md5_list(struct sock *sk)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
struct tcp_md5sig_key *key;
|
|
struct hlist_node *n;
|
|
struct tcp_md5sig_info *md5sig;
|
|
|
|
md5sig = rcu_dereference_protected(tp->md5sig_info, 1);
|
|
|
|
hlist_for_each_entry_safe(key, n, &md5sig->head, node) {
|
|
hlist_del_rcu(&key->node);
|
|
atomic_sub(sizeof(*key), &sk->sk_omem_alloc);
|
|
kfree_rcu(key, rcu);
|
|
}
|
|
}
|
|
|
|
static int tcp_v4_parse_md5_keys(struct sock *sk, int optname,
|
|
char __user *optval, int optlen)
|
|
{
|
|
struct tcp_md5sig cmd;
|
|
struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr;
|
|
u8 prefixlen = 32;
|
|
|
|
if (optlen < sizeof(cmd))
|
|
return -EINVAL;
|
|
|
|
if (copy_from_user(&cmd, optval, sizeof(cmd)))
|
|
return -EFAULT;
|
|
|
|
if (sin->sin_family != AF_INET)
|
|
return -EINVAL;
|
|
|
|
if (optname == TCP_MD5SIG_EXT &&
|
|
cmd.tcpm_flags & TCP_MD5SIG_FLAG_PREFIX) {
|
|
prefixlen = cmd.tcpm_prefixlen;
|
|
if (prefixlen > 32)
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (!cmd.tcpm_keylen)
|
|
return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr,
|
|
AF_INET, prefixlen);
|
|
|
|
if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN)
|
|
return -EINVAL;
|
|
|
|
return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr,
|
|
AF_INET, prefixlen, cmd.tcpm_key, cmd.tcpm_keylen,
|
|
GFP_KERNEL);
|
|
}
|
|
|
|
static int tcp_v4_md5_hash_headers(struct tcp_md5sig_pool *hp,
|
|
__be32 daddr, __be32 saddr,
|
|
const struct tcphdr *th, int nbytes)
|
|
{
|
|
struct tcp4_pseudohdr *bp;
|
|
struct scatterlist sg;
|
|
struct tcphdr *_th;
|
|
|
|
bp = hp->scratch;
|
|
bp->saddr = saddr;
|
|
bp->daddr = daddr;
|
|
bp->pad = 0;
|
|
bp->protocol = IPPROTO_TCP;
|
|
bp->len = cpu_to_be16(nbytes);
|
|
|
|
_th = (struct tcphdr *)(bp + 1);
|
|
memcpy(_th, th, sizeof(*th));
|
|
_th->check = 0;
|
|
|
|
sg_init_one(&sg, bp, sizeof(*bp) + sizeof(*th));
|
|
ahash_request_set_crypt(hp->md5_req, &sg, NULL,
|
|
sizeof(*bp) + sizeof(*th));
|
|
return crypto_ahash_update(hp->md5_req);
|
|
}
|
|
|
|
static int tcp_v4_md5_hash_hdr(char *md5_hash, const struct tcp_md5sig_key *key,
|
|
__be32 daddr, __be32 saddr, const struct tcphdr *th)
|
|
{
|
|
struct tcp_md5sig_pool *hp;
|
|
struct ahash_request *req;
|
|
|
|
hp = tcp_get_md5sig_pool();
|
|
if (!hp)
|
|
goto clear_hash_noput;
|
|
req = hp->md5_req;
|
|
|
|
if (crypto_ahash_init(req))
|
|
goto clear_hash;
|
|
if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, th->doff << 2))
|
|
goto clear_hash;
|
|
if (tcp_md5_hash_key(hp, key))
|
|
goto clear_hash;
|
|
ahash_request_set_crypt(req, NULL, md5_hash, 0);
|
|
if (crypto_ahash_final(req))
|
|
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;
|
|
}
|
|
|
|
int tcp_v4_md5_hash_skb(char *md5_hash, const struct tcp_md5sig_key *key,
|
|
const struct sock *sk,
|
|
const struct sk_buff *skb)
|
|
{
|
|
struct tcp_md5sig_pool *hp;
|
|
struct ahash_request *req;
|
|
const struct tcphdr *th = tcp_hdr(skb);
|
|
__be32 saddr, daddr;
|
|
|
|
if (sk) { /* valid for establish/request sockets */
|
|
saddr = sk->sk_rcv_saddr;
|
|
daddr = sk->sk_daddr;
|
|
} else {
|
|
const struct iphdr *iph = ip_hdr(skb);
|
|
saddr = iph->saddr;
|
|
daddr = iph->daddr;
|
|
}
|
|
|
|
hp = tcp_get_md5sig_pool();
|
|
if (!hp)
|
|
goto clear_hash_noput;
|
|
req = hp->md5_req;
|
|
|
|
if (crypto_ahash_init(req))
|
|
goto clear_hash;
|
|
|
|
if (tcp_v4_md5_hash_headers(hp, daddr, saddr, th, skb->len))
|
|
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;
|
|
ahash_request_set_crypt(req, NULL, md5_hash, 0);
|
|
if (crypto_ahash_final(req))
|
|
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;
|
|
}
|
|
EXPORT_SYMBOL(tcp_v4_md5_hash_skb);
|
|
|
|
#endif
|
|
|
|
/* Called with rcu_read_lock() */
|
|
static bool tcp_v4_inbound_md5_hash(const struct sock *sk,
|
|
const struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
/*
|
|
* This gets called for each TCP segment that arrives
|
|
* so we want to be efficient.
|
|
* We have 3 drop cases:
|
|
* o No MD5 hash and one expected.
|
|
* o MD5 hash and we're not expecting one.
|
|
* o MD5 hash and its wrong.
|
|
*/
|
|
const __u8 *hash_location = NULL;
|
|
struct tcp_md5sig_key *hash_expected;
|
|
const struct iphdr *iph = ip_hdr(skb);
|
|
const struct tcphdr *th = tcp_hdr(skb);
|
|
int genhash;
|
|
unsigned char newhash[16];
|
|
|
|
hash_expected = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&iph->saddr,
|
|
AF_INET);
|
|
hash_location = tcp_parse_md5sig_option(th);
|
|
|
|
/* We've parsed the options - do we have a hash? */
|
|
if (!hash_expected && !hash_location)
|
|
return false;
|
|
|
|
if (hash_expected && !hash_location) {
|
|
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND);
|
|
return true;
|
|
}
|
|
|
|
if (!hash_expected && hash_location) {
|
|
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED);
|
|
return true;
|
|
}
|
|
|
|
/* Okay, so this is hash_expected and hash_location -
|
|
* so we need to calculate the checksum.
|
|
*/
|
|
genhash = tcp_v4_md5_hash_skb(newhash,
|
|
hash_expected,
|
|
NULL, skb);
|
|
|
|
if (genhash || memcmp(hash_location, newhash, 16) != 0) {
|
|
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE);
|
|
net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s\n",
|
|
&iph->saddr, ntohs(th->source),
|
|
&iph->daddr, ntohs(th->dest),
|
|
genhash ? " tcp_v4_calc_md5_hash failed"
|
|
: "");
|
|
return true;
|
|
}
|
|
return false;
|
|
#endif
|
|
return false;
|
|
}
|
|
|
|
static void tcp_v4_init_req(struct request_sock *req,
|
|
const struct sock *sk_listener,
|
|
struct sk_buff *skb)
|
|
{
|
|
struct inet_request_sock *ireq = inet_rsk(req);
|
|
struct net *net = sock_net(sk_listener);
|
|
|
|
sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr);
|
|
sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr);
|
|
RCU_INIT_POINTER(ireq->ireq_opt, tcp_v4_save_options(net, skb));
|
|
}
|
|
|
|
static struct dst_entry *tcp_v4_route_req(const struct sock *sk,
|
|
struct flowi *fl,
|
|
const struct request_sock *req)
|
|
{
|
|
return inet_csk_route_req(sk, &fl->u.ip4, req);
|
|
}
|
|
|
|
struct request_sock_ops tcp_request_sock_ops __read_mostly = {
|
|
.family = PF_INET,
|
|
.obj_size = sizeof(struct tcp_request_sock),
|
|
.rtx_syn_ack = tcp_rtx_synack,
|
|
.send_ack = tcp_v4_reqsk_send_ack,
|
|
.destructor = tcp_v4_reqsk_destructor,
|
|
.send_reset = tcp_v4_send_reset,
|
|
.syn_ack_timeout = tcp_syn_ack_timeout,
|
|
};
|
|
|
|
static const struct tcp_request_sock_ops tcp_request_sock_ipv4_ops = {
|
|
.mss_clamp = TCP_MSS_DEFAULT,
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
.req_md5_lookup = tcp_v4_md5_lookup,
|
|
.calc_md5_hash = tcp_v4_md5_hash_skb,
|
|
#endif
|
|
.init_req = tcp_v4_init_req,
|
|
#ifdef CONFIG_SYN_COOKIES
|
|
.cookie_init_seq = cookie_v4_init_sequence,
|
|
#endif
|
|
.route_req = tcp_v4_route_req,
|
|
.init_seq = tcp_v4_init_seq,
|
|
.init_ts_off = tcp_v4_init_ts_off,
|
|
.send_synack = tcp_v4_send_synack,
|
|
};
|
|
|
|
int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
/* Never answer to SYNs send to broadcast or multicast */
|
|
if (skb_rtable(skb)->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST))
|
|
goto drop;
|
|
|
|
return tcp_conn_request(&tcp_request_sock_ops,
|
|
&tcp_request_sock_ipv4_ops, sk, skb);
|
|
|
|
drop:
|
|
tcp_listendrop(sk);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(tcp_v4_conn_request);
|
|
|
|
|
|
/*
|
|
* The three way handshake has completed - we got a valid synack -
|
|
* now create the new socket.
|
|
*/
|
|
struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb,
|
|
struct request_sock *req,
|
|
struct dst_entry *dst,
|
|
struct request_sock *req_unhash,
|
|
bool *own_req)
|
|
{
|
|
struct inet_request_sock *ireq;
|
|
struct inet_sock *newinet;
|
|
struct tcp_sock *newtp;
|
|
struct sock *newsk;
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
struct tcp_md5sig_key *key;
|
|
#endif
|
|
struct ip_options_rcu *inet_opt;
|
|
|
|
if (sk_acceptq_is_full(sk))
|
|
goto exit_overflow;
|
|
|
|
newsk = tcp_create_openreq_child(sk, req, skb);
|
|
if (!newsk)
|
|
goto exit_nonewsk;
|
|
|
|
newsk->sk_gso_type = SKB_GSO_TCPV4;
|
|
inet_sk_rx_dst_set(newsk, skb);
|
|
|
|
newtp = tcp_sk(newsk);
|
|
newinet = inet_sk(newsk);
|
|
ireq = inet_rsk(req);
|
|
sk_daddr_set(newsk, ireq->ir_rmt_addr);
|
|
sk_rcv_saddr_set(newsk, ireq->ir_loc_addr);
|
|
newsk->sk_bound_dev_if = ireq->ir_iif;
|
|
newinet->inet_saddr = ireq->ir_loc_addr;
|
|
inet_opt = rcu_dereference(ireq->ireq_opt);
|
|
RCU_INIT_POINTER(newinet->inet_opt, inet_opt);
|
|
newinet->mc_index = inet_iif(skb);
|
|
newinet->mc_ttl = ip_hdr(skb)->ttl;
|
|
newinet->rcv_tos = ip_hdr(skb)->tos;
|
|
inet_csk(newsk)->icsk_ext_hdr_len = 0;
|
|
if (inet_opt)
|
|
inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen;
|
|
newinet->inet_id = newtp->write_seq ^ jiffies;
|
|
|
|
if (!dst) {
|
|
dst = inet_csk_route_child_sock(sk, newsk, req);
|
|
if (!dst)
|
|
goto put_and_exit;
|
|
} else {
|
|
/* syncookie case : see end of cookie_v4_check() */
|
|
}
|
|
sk_setup_caps(newsk, dst);
|
|
|
|
tcp_ca_openreq_child(newsk, dst);
|
|
|
|
tcp_sync_mss(newsk, dst_mtu(dst));
|
|
newtp->advmss = tcp_mss_clamp(tcp_sk(sk), dst_metric_advmss(dst));
|
|
|
|
tcp_initialize_rcv_mss(newsk);
|
|
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
/* Copy over the MD5 key from the original socket */
|
|
key = tcp_md5_do_lookup(sk, (union tcp_md5_addr *)&newinet->inet_daddr,
|
|
AF_INET);
|
|
if (key) {
|
|
/*
|
|
* We're using one, so create a matching key
|
|
* on the newsk structure. If we fail to get
|
|
* memory, then we end up not copying the key
|
|
* across. Shucks.
|
|
*/
|
|
tcp_md5_do_add(newsk, (union tcp_md5_addr *)&newinet->inet_daddr,
|
|
AF_INET, 32, key->key, key->keylen, GFP_ATOMIC);
|
|
sk_nocaps_add(newsk, NETIF_F_GSO_MASK);
|
|
}
|
|
#endif
|
|
|
|
if (__inet_inherit_port(sk, newsk) < 0)
|
|
goto put_and_exit;
|
|
*own_req = inet_ehash_nolisten(newsk, req_to_sk(req_unhash));
|
|
if (likely(*own_req)) {
|
|
tcp_move_syn(newtp, req);
|
|
ireq->ireq_opt = NULL;
|
|
} else {
|
|
newinet->inet_opt = NULL;
|
|
}
|
|
return newsk;
|
|
|
|
exit_overflow:
|
|
NET_INC_STATS(sock_net(sk), LINUX_MIB_LISTENOVERFLOWS);
|
|
exit_nonewsk:
|
|
dst_release(dst);
|
|
exit:
|
|
tcp_listendrop(sk);
|
|
return NULL;
|
|
put_and_exit:
|
|
newinet->inet_opt = NULL;
|
|
inet_csk_prepare_forced_close(newsk);
|
|
tcp_done(newsk);
|
|
goto exit;
|
|
}
|
|
EXPORT_SYMBOL(tcp_v4_syn_recv_sock);
|
|
|
|
static struct sock *tcp_v4_cookie_check(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
#ifdef CONFIG_SYN_COOKIES
|
|
const struct tcphdr *th = tcp_hdr(skb);
|
|
|
|
if (!th->syn)
|
|
sk = cookie_v4_check(sk, skb);
|
|
#endif
|
|
return sk;
|
|
}
|
|
|
|
/* The socket must have it's spinlock held when we get
|
|
* here, unless it is a TCP_LISTEN socket.
|
|
*
|
|
* 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.
|
|
*/
|
|
int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct sock *rsk;
|
|
|
|
if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
|
|
struct dst_entry *dst = sk->sk_rx_dst;
|
|
|
|
sock_rps_save_rxhash(sk, skb);
|
|
sk_mark_napi_id(sk, skb);
|
|
if (dst) {
|
|
if (inet_sk(sk)->rx_dst_ifindex != skb->skb_iif ||
|
|
!dst->ops->check(dst, 0)) {
|
|
dst_release(dst);
|
|
sk->sk_rx_dst = NULL;
|
|
}
|
|
}
|
|
tcp_rcv_established(sk, skb);
|
|
return 0;
|
|
}
|
|
|
|
if (tcp_checksum_complete(skb))
|
|
goto csum_err;
|
|
|
|
if (sk->sk_state == TCP_LISTEN) {
|
|
struct sock *nsk = tcp_v4_cookie_check(sk, skb);
|
|
|
|
if (!nsk)
|
|
goto discard;
|
|
if (nsk != sk) {
|
|
if (tcp_child_process(sk, nsk, skb)) {
|
|
rsk = nsk;
|
|
goto reset;
|
|
}
|
|
return 0;
|
|
}
|
|
} else
|
|
sock_rps_save_rxhash(sk, skb);
|
|
|
|
if (tcp_rcv_state_process(sk, skb)) {
|
|
rsk = sk;
|
|
goto reset;
|
|
}
|
|
return 0;
|
|
|
|
reset:
|
|
tcp_v4_send_reset(rsk, skb);
|
|
discard:
|
|
kfree_skb(skb);
|
|
/* Be careful here. If this function gets more complicated and
|
|
* gcc suffers from register pressure on the x86, sk (in %ebx)
|
|
* might be destroyed here. This current version compiles correctly,
|
|
* but you have been warned.
|
|
*/
|
|
return 0;
|
|
|
|
csum_err:
|
|
TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
|
|
TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
|
|
goto discard;
|
|
}
|
|
EXPORT_SYMBOL(tcp_v4_do_rcv);
|
|
|
|
int tcp_v4_early_demux(struct sk_buff *skb)
|
|
{
|
|
const struct iphdr *iph;
|
|
const struct tcphdr *th;
|
|
struct sock *sk;
|
|
|
|
if (skb->pkt_type != PACKET_HOST)
|
|
return 0;
|
|
|
|
if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr)))
|
|
return 0;
|
|
|
|
iph = ip_hdr(skb);
|
|
th = tcp_hdr(skb);
|
|
|
|
if (th->doff < sizeof(struct tcphdr) / 4)
|
|
return 0;
|
|
|
|
sk = __inet_lookup_established(dev_net(skb->dev), &tcp_hashinfo,
|
|
iph->saddr, th->source,
|
|
iph->daddr, ntohs(th->dest),
|
|
skb->skb_iif, inet_sdif(skb));
|
|
if (sk) {
|
|
skb->sk = sk;
|
|
skb->destructor = sock_edemux;
|
|
if (sk_fullsock(sk)) {
|
|
struct dst_entry *dst = READ_ONCE(sk->sk_rx_dst);
|
|
|
|
if (dst)
|
|
dst = dst_check(dst, 0);
|
|
if (dst &&
|
|
inet_sk(sk)->rx_dst_ifindex == skb->skb_iif)
|
|
skb_dst_set_noref(skb, dst);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
u32 limit = sk->sk_rcvbuf + sk->sk_sndbuf;
|
|
struct skb_shared_info *shinfo;
|
|
const struct tcphdr *th;
|
|
struct tcphdr *thtail;
|
|
struct sk_buff *tail;
|
|
unsigned int hdrlen;
|
|
bool fragstolen;
|
|
u32 gso_segs;
|
|
int delta;
|
|
|
|
/* In case all data was pulled from skb frags (in __pskb_pull_tail()),
|
|
* we can fix skb->truesize to its real value to avoid future drops.
|
|
* This is valid because skb is not yet charged to the socket.
|
|
* It has been noticed pure SACK packets were sometimes dropped
|
|
* (if cooked by drivers without copybreak feature).
|
|
*/
|
|
skb_condense(skb);
|
|
|
|
skb_dst_drop(skb);
|
|
|
|
if (unlikely(tcp_checksum_complete(skb))) {
|
|
bh_unlock_sock(sk);
|
|
__TCP_INC_STATS(sock_net(sk), TCP_MIB_CSUMERRORS);
|
|
__TCP_INC_STATS(sock_net(sk), TCP_MIB_INERRS);
|
|
return true;
|
|
}
|
|
|
|
/* Attempt coalescing to last skb in backlog, even if we are
|
|
* above the limits.
|
|
* This is okay because skb capacity is limited to MAX_SKB_FRAGS.
|
|
*/
|
|
th = (const struct tcphdr *)skb->data;
|
|
hdrlen = th->doff * 4;
|
|
shinfo = skb_shinfo(skb);
|
|
|
|
if (!shinfo->gso_size)
|
|
shinfo->gso_size = skb->len - hdrlen;
|
|
|
|
if (!shinfo->gso_segs)
|
|
shinfo->gso_segs = 1;
|
|
|
|
tail = sk->sk_backlog.tail;
|
|
if (!tail)
|
|
goto no_coalesce;
|
|
thtail = (struct tcphdr *)tail->data;
|
|
|
|
if (TCP_SKB_CB(tail)->end_seq != TCP_SKB_CB(skb)->seq ||
|
|
TCP_SKB_CB(tail)->ip_dsfield != TCP_SKB_CB(skb)->ip_dsfield ||
|
|
((TCP_SKB_CB(tail)->tcp_flags |
|
|
TCP_SKB_CB(skb)->tcp_flags) & (TCPHDR_SYN | TCPHDR_RST | TCPHDR_URG)) ||
|
|
!((TCP_SKB_CB(tail)->tcp_flags &
|
|
TCP_SKB_CB(skb)->tcp_flags) & TCPHDR_ACK) ||
|
|
((TCP_SKB_CB(tail)->tcp_flags ^
|
|
TCP_SKB_CB(skb)->tcp_flags) & (TCPHDR_ECE | TCPHDR_CWR)) ||
|
|
#ifdef CONFIG_TLS_DEVICE
|
|
tail->decrypted != skb->decrypted ||
|
|
#endif
|
|
thtail->doff != th->doff ||
|
|
memcmp(thtail + 1, th + 1, hdrlen - sizeof(*th)))
|
|
goto no_coalesce;
|
|
|
|
__skb_pull(skb, hdrlen);
|
|
if (skb_try_coalesce(tail, skb, &fragstolen, &delta)) {
|
|
thtail->window = th->window;
|
|
|
|
TCP_SKB_CB(tail)->end_seq = TCP_SKB_CB(skb)->end_seq;
|
|
|
|
if (after(TCP_SKB_CB(skb)->ack_seq, TCP_SKB_CB(tail)->ack_seq))
|
|
TCP_SKB_CB(tail)->ack_seq = TCP_SKB_CB(skb)->ack_seq;
|
|
|
|
/* We have to update both TCP_SKB_CB(tail)->tcp_flags and
|
|
* thtail->fin, so that the fast path in tcp_rcv_established()
|
|
* is not entered if we append a packet with a FIN.
|
|
* SYN, RST, URG are not present.
|
|
* ACK is set on both packets.
|
|
* PSH : we do not really care in TCP stack,
|
|
* at least for 'GRO' packets.
|
|
*/
|
|
thtail->fin |= th->fin;
|
|
TCP_SKB_CB(tail)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags;
|
|
|
|
if (TCP_SKB_CB(skb)->has_rxtstamp) {
|
|
TCP_SKB_CB(tail)->has_rxtstamp = true;
|
|
tail->tstamp = skb->tstamp;
|
|
skb_hwtstamps(tail)->hwtstamp = skb_hwtstamps(skb)->hwtstamp;
|
|
}
|
|
|
|
/* Not as strict as GRO. We only need to carry mss max value */
|
|
skb_shinfo(tail)->gso_size = max(shinfo->gso_size,
|
|
skb_shinfo(tail)->gso_size);
|
|
|
|
gso_segs = skb_shinfo(tail)->gso_segs + shinfo->gso_segs;
|
|
skb_shinfo(tail)->gso_segs = min_t(u32, gso_segs, 0xFFFF);
|
|
|
|
sk->sk_backlog.len += delta;
|
|
__NET_INC_STATS(sock_net(sk),
|
|
LINUX_MIB_TCPBACKLOGCOALESCE);
|
|
kfree_skb_partial(skb, fragstolen);
|
|
return false;
|
|
}
|
|
__skb_push(skb, hdrlen);
|
|
|
|
no_coalesce:
|
|
/* Only socket owner can try to collapse/prune rx queues
|
|
* to reduce memory overhead, so add a little headroom here.
|
|
* Few sockets backlog are possibly concurrently non empty.
|
|
*/
|
|
limit += 64*1024;
|
|
|
|
if (unlikely(sk_add_backlog(sk, skb, limit))) {
|
|
bh_unlock_sock(sk);
|
|
__NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPBACKLOGDROP);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
EXPORT_SYMBOL(tcp_add_backlog);
|
|
|
|
int tcp_filter(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct tcphdr *th = (struct tcphdr *)skb->data;
|
|
|
|
return sk_filter_trim_cap(sk, skb, th->doff * 4);
|
|
}
|
|
EXPORT_SYMBOL(tcp_filter);
|
|
|
|
static void tcp_v4_restore_cb(struct sk_buff *skb)
|
|
{
|
|
memmove(IPCB(skb), &TCP_SKB_CB(skb)->header.h4,
|
|
sizeof(struct inet_skb_parm));
|
|
}
|
|
|
|
static void tcp_v4_fill_cb(struct sk_buff *skb, const struct iphdr *iph,
|
|
const struct tcphdr *th)
|
|
{
|
|
/* This is tricky : We move IPCB at its correct location into TCP_SKB_CB()
|
|
* barrier() makes sure compiler wont play fool^Waliasing games.
|
|
*/
|
|
memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb),
|
|
sizeof(struct inet_skb_parm));
|
|
barrier();
|
|
|
|
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)->tcp_flags = tcp_flag_byte(th);
|
|
TCP_SKB_CB(skb)->tcp_tw_isn = 0;
|
|
TCP_SKB_CB(skb)->ip_dsfield = ipv4_get_dsfield(iph);
|
|
TCP_SKB_CB(skb)->sacked = 0;
|
|
TCP_SKB_CB(skb)->has_rxtstamp =
|
|
skb->tstamp || skb_hwtstamps(skb)->hwtstamp;
|
|
}
|
|
|
|
/*
|
|
* From tcp_input.c
|
|
*/
|
|
|
|
int tcp_v4_rcv(struct sk_buff *skb)
|
|
{
|
|
struct net *net = dev_net(skb->dev);
|
|
struct sk_buff *skb_to_free;
|
|
int sdif = inet_sdif(skb);
|
|
const struct iphdr *iph;
|
|
const struct tcphdr *th;
|
|
bool refcounted;
|
|
struct sock *sk;
|
|
int ret;
|
|
|
|
if (skb->pkt_type != PACKET_HOST)
|
|
goto discard_it;
|
|
|
|
/* Count it even if it's bad */
|
|
__TCP_INC_STATS(net, TCP_MIB_INSEGS);
|
|
|
|
if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
|
|
goto discard_it;
|
|
|
|
th = (const struct tcphdr *)skb->data;
|
|
|
|
if (unlikely(th->doff < sizeof(struct tcphdr) / 4))
|
|
goto bad_packet;
|
|
if (!pskb_may_pull(skb, th->doff * 4))
|
|
goto discard_it;
|
|
|
|
/* An explanation is required here, I think.
|
|
* Packet length and doff are validated by header prediction,
|
|
* provided case of th->doff==0 is eliminated.
|
|
* So, we defer the checks. */
|
|
|
|
if (skb_checksum_init(skb, IPPROTO_TCP, inet_compute_pseudo))
|
|
goto csum_error;
|
|
|
|
th = (const struct tcphdr *)skb->data;
|
|
iph = ip_hdr(skb);
|
|
lookup:
|
|
sk = __inet_lookup_skb(&tcp_hashinfo, skb, __tcp_hdrlen(th), th->source,
|
|
th->dest, sdif, &refcounted);
|
|
if (!sk)
|
|
goto no_tcp_socket;
|
|
|
|
process:
|
|
if (sk->sk_state == TCP_TIME_WAIT)
|
|
goto do_time_wait;
|
|
|
|
if (sk->sk_state == TCP_NEW_SYN_RECV) {
|
|
struct request_sock *req = inet_reqsk(sk);
|
|
bool req_stolen = false;
|
|
struct sock *nsk;
|
|
|
|
sk = req->rsk_listener;
|
|
if (unlikely(tcp_v4_inbound_md5_hash(sk, skb))) {
|
|
sk_drops_add(sk, skb);
|
|
reqsk_put(req);
|
|
goto discard_it;
|
|
}
|
|
if (tcp_checksum_complete(skb)) {
|
|
reqsk_put(req);
|
|
goto csum_error;
|
|
}
|
|
if (unlikely(sk->sk_state != TCP_LISTEN)) {
|
|
inet_csk_reqsk_queue_drop_and_put(sk, req);
|
|
goto lookup;
|
|
}
|
|
/* We own a reference on the listener, increase it again
|
|
* as we might lose it too soon.
|
|
*/
|
|
sock_hold(sk);
|
|
refcounted = true;
|
|
nsk = NULL;
|
|
if (!tcp_filter(sk, skb)) {
|
|
th = (const struct tcphdr *)skb->data;
|
|
iph = ip_hdr(skb);
|
|
tcp_v4_fill_cb(skb, iph, th);
|
|
nsk = tcp_check_req(sk, skb, req, false, &req_stolen);
|
|
}
|
|
if (!nsk) {
|
|
reqsk_put(req);
|
|
if (req_stolen) {
|
|
/* Another cpu got exclusive access to req
|
|
* and created a full blown socket.
|
|
* Try to feed this packet to this socket
|
|
* instead of discarding it.
|
|
*/
|
|
tcp_v4_restore_cb(skb);
|
|
sock_put(sk);
|
|
goto lookup;
|
|
}
|
|
goto discard_and_relse;
|
|
}
|
|
if (nsk == sk) {
|
|
reqsk_put(req);
|
|
tcp_v4_restore_cb(skb);
|
|
} else if (tcp_child_process(sk, nsk, skb)) {
|
|
tcp_v4_send_reset(nsk, skb);
|
|
goto discard_and_relse;
|
|
} else {
|
|
sock_put(sk);
|
|
return 0;
|
|
}
|
|
}
|
|
if (unlikely(iph->ttl < inet_sk(sk)->min_ttl)) {
|
|
__NET_INC_STATS(net, LINUX_MIB_TCPMINTTLDROP);
|
|
goto discard_and_relse;
|
|
}
|
|
|
|
if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
|
|
goto discard_and_relse;
|
|
|
|
if (tcp_v4_inbound_md5_hash(sk, skb))
|
|
goto discard_and_relse;
|
|
|
|
nf_reset(skb);
|
|
|
|
if (tcp_filter(sk, skb))
|
|
goto discard_and_relse;
|
|
th = (const struct tcphdr *)skb->data;
|
|
iph = ip_hdr(skb);
|
|
tcp_v4_fill_cb(skb, iph, th);
|
|
|
|
skb->dev = NULL;
|
|
|
|
if (sk->sk_state == TCP_LISTEN) {
|
|
ret = tcp_v4_do_rcv(sk, skb);
|
|
goto put_and_return;
|
|
}
|
|
|
|
sk_incoming_cpu_update(sk);
|
|
|
|
bh_lock_sock_nested(sk);
|
|
tcp_segs_in(tcp_sk(sk), skb);
|
|
ret = 0;
|
|
if (!sock_owned_by_user(sk)) {
|
|
skb_to_free = sk->sk_rx_skb_cache;
|
|
sk->sk_rx_skb_cache = NULL;
|
|
ret = tcp_v4_do_rcv(sk, skb);
|
|
} else {
|
|
if (tcp_add_backlog(sk, skb))
|
|
goto discard_and_relse;
|
|
skb_to_free = NULL;
|
|
}
|
|
bh_unlock_sock(sk);
|
|
if (skb_to_free)
|
|
__kfree_skb(skb_to_free);
|
|
|
|
put_and_return:
|
|
if (refcounted)
|
|
sock_put(sk);
|
|
|
|
return ret;
|
|
|
|
no_tcp_socket:
|
|
if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
|
|
goto discard_it;
|
|
|
|
tcp_v4_fill_cb(skb, iph, th);
|
|
|
|
if (tcp_checksum_complete(skb)) {
|
|
csum_error:
|
|
__TCP_INC_STATS(net, TCP_MIB_CSUMERRORS);
|
|
bad_packet:
|
|
__TCP_INC_STATS(net, TCP_MIB_INERRS);
|
|
} else {
|
|
tcp_v4_send_reset(NULL, skb);
|
|
}
|
|
|
|
discard_it:
|
|
/* Discard frame. */
|
|
kfree_skb(skb);
|
|
return 0;
|
|
|
|
discard_and_relse:
|
|
sk_drops_add(sk, skb);
|
|
if (refcounted)
|
|
sock_put(sk);
|
|
goto discard_it;
|
|
|
|
do_time_wait:
|
|
if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) {
|
|
inet_twsk_put(inet_twsk(sk));
|
|
goto discard_it;
|
|
}
|
|
|
|
tcp_v4_fill_cb(skb, iph, th);
|
|
|
|
if (tcp_checksum_complete(skb)) {
|
|
inet_twsk_put(inet_twsk(sk));
|
|
goto csum_error;
|
|
}
|
|
switch (tcp_timewait_state_process(inet_twsk(sk), skb, th)) {
|
|
case TCP_TW_SYN: {
|
|
struct sock *sk2 = inet_lookup_listener(dev_net(skb->dev),
|
|
&tcp_hashinfo, skb,
|
|
__tcp_hdrlen(th),
|
|
iph->saddr, th->source,
|
|
iph->daddr, th->dest,
|
|
inet_iif(skb),
|
|
sdif);
|
|
if (sk2) {
|
|
inet_twsk_deschedule_put(inet_twsk(sk));
|
|
sk = sk2;
|
|
tcp_v4_restore_cb(skb);
|
|
refcounted = false;
|
|
goto process;
|
|
}
|
|
}
|
|
/* to ACK */
|
|
/* fall through */
|
|
case TCP_TW_ACK:
|
|
tcp_v4_timewait_ack(sk, skb);
|
|
break;
|
|
case TCP_TW_RST:
|
|
tcp_v4_send_reset(sk, skb);
|
|
inet_twsk_deschedule_put(inet_twsk(sk));
|
|
goto discard_it;
|
|
case TCP_TW_SUCCESS:;
|
|
}
|
|
goto discard_it;
|
|
}
|
|
|
|
static struct timewait_sock_ops tcp_timewait_sock_ops = {
|
|
.twsk_obj_size = sizeof(struct tcp_timewait_sock),
|
|
.twsk_unique = tcp_twsk_unique,
|
|
.twsk_destructor= tcp_twsk_destructor,
|
|
};
|
|
|
|
void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb)
|
|
{
|
|
struct dst_entry *dst = skb_dst(skb);
|
|
|
|
if (dst && dst_hold_safe(dst)) {
|
|
sk->sk_rx_dst = dst;
|
|
inet_sk(sk)->rx_dst_ifindex = skb->skb_iif;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(inet_sk_rx_dst_set);
|
|
|
|
const struct inet_connection_sock_af_ops ipv4_specific = {
|
|
.queue_xmit = ip_queue_xmit,
|
|
.send_check = tcp_v4_send_check,
|
|
.rebuild_header = inet_sk_rebuild_header,
|
|
.sk_rx_dst_set = inet_sk_rx_dst_set,
|
|
.conn_request = tcp_v4_conn_request,
|
|
.syn_recv_sock = tcp_v4_syn_recv_sock,
|
|
.net_header_len = sizeof(struct iphdr),
|
|
.setsockopt = ip_setsockopt,
|
|
.getsockopt = ip_getsockopt,
|
|
.addr2sockaddr = inet_csk_addr2sockaddr,
|
|
.sockaddr_len = sizeof(struct sockaddr_in),
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_setsockopt = compat_ip_setsockopt,
|
|
.compat_getsockopt = compat_ip_getsockopt,
|
|
#endif
|
|
.mtu_reduced = tcp_v4_mtu_reduced,
|
|
};
|
|
EXPORT_SYMBOL(ipv4_specific);
|
|
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
static const struct tcp_sock_af_ops tcp_sock_ipv4_specific = {
|
|
.md5_lookup = tcp_v4_md5_lookup,
|
|
.calc_md5_hash = tcp_v4_md5_hash_skb,
|
|
.md5_parse = tcp_v4_parse_md5_keys,
|
|
};
|
|
#endif
|
|
|
|
/* NOTE: A lot of things set to zero explicitly by call to
|
|
* sk_alloc() so need not be done here.
|
|
*/
|
|
static int tcp_v4_init_sock(struct sock *sk)
|
|
{
|
|
struct inet_connection_sock *icsk = inet_csk(sk);
|
|
|
|
tcp_init_sock(sk);
|
|
|
|
icsk->icsk_af_ops = &ipv4_specific;
|
|
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
tcp_sk(sk)->af_specific = &tcp_sock_ipv4_specific;
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
void tcp_v4_destroy_sock(struct sock *sk)
|
|
{
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
|
|
trace_tcp_destroy_sock(sk);
|
|
|
|
tcp_clear_xmit_timers(sk);
|
|
|
|
tcp_cleanup_congestion_control(sk);
|
|
|
|
tcp_cleanup_ulp(sk);
|
|
|
|
/* Cleanup up the write buffer. */
|
|
tcp_write_queue_purge(sk);
|
|
|
|
/* Check if we want to disable active TFO */
|
|
tcp_fastopen_active_disable_ofo_check(sk);
|
|
|
|
/* Cleans up our, hopefully empty, out_of_order_queue. */
|
|
skb_rbtree_purge(&tp->out_of_order_queue);
|
|
|
|
#ifdef CONFIG_TCP_MD5SIG
|
|
/* Clean up the MD5 key list, if any */
|
|
if (tp->md5sig_info) {
|
|
tcp_clear_md5_list(sk);
|
|
kfree_rcu(rcu_dereference_protected(tp->md5sig_info, 1), rcu);
|
|
tp->md5sig_info = NULL;
|
|
}
|
|
#endif
|
|
|
|
/* Clean up a referenced TCP bind bucket. */
|
|
if (inet_csk(sk)->icsk_bind_hash)
|
|
inet_put_port(sk);
|
|
|
|
BUG_ON(tp->fastopen_rsk);
|
|
|
|
/* If socket is aborted during connect operation */
|
|
tcp_free_fastopen_req(tp);
|
|
tcp_fastopen_destroy_cipher(sk);
|
|
tcp_saved_syn_free(tp);
|
|
|
|
sk_sockets_allocated_dec(sk);
|
|
}
|
|
EXPORT_SYMBOL(tcp_v4_destroy_sock);
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
/* Proc filesystem TCP sock list dumping. */
|
|
|
|
/*
|
|
* Get next listener socket follow cur. If cur is NULL, get first socket
|
|
* starting from bucket given in st->bucket; when st->bucket is zero the
|
|
* very first socket in the hash table is returned.
|
|
*/
|
|
static void *listening_get_next(struct seq_file *seq, void *cur)
|
|
{
|
|
struct tcp_seq_afinfo *afinfo = PDE_DATA(file_inode(seq->file));
|
|
struct tcp_iter_state *st = seq->private;
|
|
struct net *net = seq_file_net(seq);
|
|
struct inet_listen_hashbucket *ilb;
|
|
struct sock *sk = cur;
|
|
|
|
if (!sk) {
|
|
get_head:
|
|
ilb = &tcp_hashinfo.listening_hash[st->bucket];
|
|
spin_lock(&ilb->lock);
|
|
sk = sk_head(&ilb->head);
|
|
st->offset = 0;
|
|
goto get_sk;
|
|
}
|
|
ilb = &tcp_hashinfo.listening_hash[st->bucket];
|
|
++st->num;
|
|
++st->offset;
|
|
|
|
sk = sk_next(sk);
|
|
get_sk:
|
|
sk_for_each_from(sk) {
|
|
if (!net_eq(sock_net(sk), net))
|
|
continue;
|
|
if (sk->sk_family == afinfo->family)
|
|
return sk;
|
|
}
|
|
spin_unlock(&ilb->lock);
|
|
st->offset = 0;
|
|
if (++st->bucket < INET_LHTABLE_SIZE)
|
|
goto get_head;
|
|
return NULL;
|
|
}
|
|
|
|
static void *listening_get_idx(struct seq_file *seq, loff_t *pos)
|
|
{
|
|
struct tcp_iter_state *st = seq->private;
|
|
void *rc;
|
|
|
|
st->bucket = 0;
|
|
st->offset = 0;
|
|
rc = listening_get_next(seq, NULL);
|
|
|
|
while (rc && *pos) {
|
|
rc = listening_get_next(seq, rc);
|
|
--*pos;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static inline bool empty_bucket(const struct tcp_iter_state *st)
|
|
{
|
|
return hlist_nulls_empty(&tcp_hashinfo.ehash[st->bucket].chain);
|
|
}
|
|
|
|
/*
|
|
* Get first established socket starting from bucket given in st->bucket.
|
|
* If st->bucket is zero, the very first socket in the hash is returned.
|
|
*/
|
|
static void *established_get_first(struct seq_file *seq)
|
|
{
|
|
struct tcp_seq_afinfo *afinfo = PDE_DATA(file_inode(seq->file));
|
|
struct tcp_iter_state *st = seq->private;
|
|
struct net *net = seq_file_net(seq);
|
|
void *rc = NULL;
|
|
|
|
st->offset = 0;
|
|
for (; st->bucket <= tcp_hashinfo.ehash_mask; ++st->bucket) {
|
|
struct sock *sk;
|
|
struct hlist_nulls_node *node;
|
|
spinlock_t *lock = inet_ehash_lockp(&tcp_hashinfo, st->bucket);
|
|
|
|
/* Lockless fast path for the common case of empty buckets */
|
|
if (empty_bucket(st))
|
|
continue;
|
|
|
|
spin_lock_bh(lock);
|
|
sk_nulls_for_each(sk, node, &tcp_hashinfo.ehash[st->bucket].chain) {
|
|
if (sk->sk_family != afinfo->family ||
|
|
!net_eq(sock_net(sk), net)) {
|
|
continue;
|
|
}
|
|
rc = sk;
|
|
goto out;
|
|
}
|
|
spin_unlock_bh(lock);
|
|
}
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static void *established_get_next(struct seq_file *seq, void *cur)
|
|
{
|
|
struct tcp_seq_afinfo *afinfo = PDE_DATA(file_inode(seq->file));
|
|
struct sock *sk = cur;
|
|
struct hlist_nulls_node *node;
|
|
struct tcp_iter_state *st = seq->private;
|
|
struct net *net = seq_file_net(seq);
|
|
|
|
++st->num;
|
|
++st->offset;
|
|
|
|
sk = sk_nulls_next(sk);
|
|
|
|
sk_nulls_for_each_from(sk, node) {
|
|
if (sk->sk_family == afinfo->family &&
|
|
net_eq(sock_net(sk), net))
|
|
return sk;
|
|
}
|
|
|
|
spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket));
|
|
++st->bucket;
|
|
return established_get_first(seq);
|
|
}
|
|
|
|
static void *established_get_idx(struct seq_file *seq, loff_t pos)
|
|
{
|
|
struct tcp_iter_state *st = seq->private;
|
|
void *rc;
|
|
|
|
st->bucket = 0;
|
|
rc = established_get_first(seq);
|
|
|
|
while (rc && pos) {
|
|
rc = established_get_next(seq, rc);
|
|
--pos;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static void *tcp_get_idx(struct seq_file *seq, loff_t pos)
|
|
{
|
|
void *rc;
|
|
struct tcp_iter_state *st = seq->private;
|
|
|
|
st->state = TCP_SEQ_STATE_LISTENING;
|
|
rc = listening_get_idx(seq, &pos);
|
|
|
|
if (!rc) {
|
|
st->state = TCP_SEQ_STATE_ESTABLISHED;
|
|
rc = established_get_idx(seq, pos);
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
static void *tcp_seek_last_pos(struct seq_file *seq)
|
|
{
|
|
struct tcp_iter_state *st = seq->private;
|
|
int offset = st->offset;
|
|
int orig_num = st->num;
|
|
void *rc = NULL;
|
|
|
|
switch (st->state) {
|
|
case TCP_SEQ_STATE_LISTENING:
|
|
if (st->bucket >= INET_LHTABLE_SIZE)
|
|
break;
|
|
st->state = TCP_SEQ_STATE_LISTENING;
|
|
rc = listening_get_next(seq, NULL);
|
|
while (offset-- && rc)
|
|
rc = listening_get_next(seq, rc);
|
|
if (rc)
|
|
break;
|
|
st->bucket = 0;
|
|
st->state = TCP_SEQ_STATE_ESTABLISHED;
|
|
/* Fallthrough */
|
|
case TCP_SEQ_STATE_ESTABLISHED:
|
|
if (st->bucket > tcp_hashinfo.ehash_mask)
|
|
break;
|
|
rc = established_get_first(seq);
|
|
while (offset-- && rc)
|
|
rc = established_get_next(seq, rc);
|
|
}
|
|
|
|
st->num = orig_num;
|
|
|
|
return rc;
|
|
}
|
|
|
|
void *tcp_seq_start(struct seq_file *seq, loff_t *pos)
|
|
{
|
|
struct tcp_iter_state *st = seq->private;
|
|
void *rc;
|
|
|
|
if (*pos && *pos == st->last_pos) {
|
|
rc = tcp_seek_last_pos(seq);
|
|
if (rc)
|
|
goto out;
|
|
}
|
|
|
|
st->state = TCP_SEQ_STATE_LISTENING;
|
|
st->num = 0;
|
|
st->bucket = 0;
|
|
st->offset = 0;
|
|
rc = *pos ? tcp_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
|
|
|
|
out:
|
|
st->last_pos = *pos;
|
|
return rc;
|
|
}
|
|
EXPORT_SYMBOL(tcp_seq_start);
|
|
|
|
void *tcp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
{
|
|
struct tcp_iter_state *st = seq->private;
|
|
void *rc = NULL;
|
|
|
|
if (v == SEQ_START_TOKEN) {
|
|
rc = tcp_get_idx(seq, 0);
|
|
goto out;
|
|
}
|
|
|
|
switch (st->state) {
|
|
case TCP_SEQ_STATE_LISTENING:
|
|
rc = listening_get_next(seq, v);
|
|
if (!rc) {
|
|
st->state = TCP_SEQ_STATE_ESTABLISHED;
|
|
st->bucket = 0;
|
|
st->offset = 0;
|
|
rc = established_get_first(seq);
|
|
}
|
|
break;
|
|
case TCP_SEQ_STATE_ESTABLISHED:
|
|
rc = established_get_next(seq, v);
|
|
break;
|
|
}
|
|
out:
|
|
++*pos;
|
|
st->last_pos = *pos;
|
|
return rc;
|
|
}
|
|
EXPORT_SYMBOL(tcp_seq_next);
|
|
|
|
void tcp_seq_stop(struct seq_file *seq, void *v)
|
|
{
|
|
struct tcp_iter_state *st = seq->private;
|
|
|
|
switch (st->state) {
|
|
case TCP_SEQ_STATE_LISTENING:
|
|
if (v != SEQ_START_TOKEN)
|
|
spin_unlock(&tcp_hashinfo.listening_hash[st->bucket].lock);
|
|
break;
|
|
case TCP_SEQ_STATE_ESTABLISHED:
|
|
if (v)
|
|
spin_unlock_bh(inet_ehash_lockp(&tcp_hashinfo, st->bucket));
|
|
break;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(tcp_seq_stop);
|
|
|
|
static void get_openreq4(const struct request_sock *req,
|
|
struct seq_file *f, int i)
|
|
{
|
|
const struct inet_request_sock *ireq = inet_rsk(req);
|
|
long delta = req->rsk_timer.expires - jiffies;
|
|
|
|
seq_printf(f, "%4d: %08X:%04X %08X:%04X"
|
|
" %02X %08X:%08X %02X:%08lX %08X %5u %8d %u %d %pK",
|
|
i,
|
|
ireq->ir_loc_addr,
|
|
ireq->ir_num,
|
|
ireq->ir_rmt_addr,
|
|
ntohs(ireq->ir_rmt_port),
|
|
TCP_SYN_RECV,
|
|
0, 0, /* could print option size, but that is af dependent. */
|
|
1, /* timers active (only the expire timer) */
|
|
jiffies_delta_to_clock_t(delta),
|
|
req->num_timeout,
|
|
from_kuid_munged(seq_user_ns(f),
|
|
sock_i_uid(req->rsk_listener)),
|
|
0, /* non standard timer */
|
|
0, /* open_requests have no inode */
|
|
0,
|
|
req);
|
|
}
|
|
|
|
static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i)
|
|
{
|
|
int timer_active;
|
|
unsigned long timer_expires;
|
|
const struct tcp_sock *tp = tcp_sk(sk);
|
|
const struct inet_connection_sock *icsk = inet_csk(sk);
|
|
const struct inet_sock *inet = inet_sk(sk);
|
|
const struct fastopen_queue *fastopenq = &icsk->icsk_accept_queue.fastopenq;
|
|
__be32 dest = inet->inet_daddr;
|
|
__be32 src = inet->inet_rcv_saddr;
|
|
__u16 destp = ntohs(inet->inet_dport);
|
|
__u16 srcp = ntohs(inet->inet_sport);
|
|
int rx_queue;
|
|
int state;
|
|
|
|
if (icsk->icsk_pending == ICSK_TIME_RETRANS ||
|
|
icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT ||
|
|
icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
|
|
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(&sk->sk_timer)) {
|
|
timer_active = 2;
|
|
timer_expires = sk->sk_timer.expires;
|
|
} else {
|
|
timer_active = 0;
|
|
timer_expires = jiffies;
|
|
}
|
|
|
|
state = inet_sk_state_load(sk);
|
|
if (state == TCP_LISTEN)
|
|
rx_queue = sk->sk_ack_backlog;
|
|
else
|
|
/* Because we don't lock the socket,
|
|
* we might find a transient negative value.
|
|
*/
|
|
rx_queue = max_t(int, tp->rcv_nxt - tp->copied_seq, 0);
|
|
|
|
seq_printf(f, "%4d: %08X:%04X %08X:%04X %02X %08X:%08X %02X:%08lX "
|
|
"%08X %5u %8d %lu %d %pK %lu %lu %u %u %d",
|
|
i, src, srcp, dest, destp, state,
|
|
tp->write_seq - tp->snd_una,
|
|
rx_queue,
|
|
timer_active,
|
|
jiffies_delta_to_clock_t(timer_expires - jiffies),
|
|
icsk->icsk_retransmits,
|
|
from_kuid_munged(seq_user_ns(f), sock_i_uid(sk)),
|
|
icsk->icsk_probes_out,
|
|
sock_i_ino(sk),
|
|
refcount_read(&sk->sk_refcnt), sk,
|
|
jiffies_to_clock_t(icsk->icsk_rto),
|
|
jiffies_to_clock_t(icsk->icsk_ack.ato),
|
|
(icsk->icsk_ack.quick << 1) | inet_csk_in_pingpong_mode(sk),
|
|
tp->snd_cwnd,
|
|
state == TCP_LISTEN ?
|
|
fastopenq->max_qlen :
|
|
(tcp_in_initial_slowstart(tp) ? -1 : tp->snd_ssthresh));
|
|
}
|
|
|
|
static void get_timewait4_sock(const struct inet_timewait_sock *tw,
|
|
struct seq_file *f, int i)
|
|
{
|
|
long delta = tw->tw_timer.expires - jiffies;
|
|
__be32 dest, src;
|
|
__u16 destp, srcp;
|
|
|
|
dest = tw->tw_daddr;
|
|
src = tw->tw_rcv_saddr;
|
|
destp = ntohs(tw->tw_dport);
|
|
srcp = ntohs(tw->tw_sport);
|
|
|
|
seq_printf(f, "%4d: %08X:%04X %08X:%04X"
|
|
" %02X %08X:%08X %02X:%08lX %08X %5d %8d %d %d %pK",
|
|
i, src, srcp, dest, destp, tw->tw_substate, 0, 0,
|
|
3, jiffies_delta_to_clock_t(delta), 0, 0, 0, 0,
|
|
refcount_read(&tw->tw_refcnt), tw);
|
|
}
|
|
|
|
#define TMPSZ 150
|
|
|
|
static int tcp4_seq_show(struct seq_file *seq, void *v)
|
|
{
|
|
struct tcp_iter_state *st;
|
|
struct sock *sk = v;
|
|
|
|
seq_setwidth(seq, TMPSZ - 1);
|
|
if (v == SEQ_START_TOKEN) {
|
|
seq_puts(seq, " sl local_address rem_address st tx_queue "
|
|
"rx_queue tr tm->when retrnsmt uid timeout "
|
|
"inode");
|
|
goto out;
|
|
}
|
|
st = seq->private;
|
|
|
|
if (sk->sk_state == TCP_TIME_WAIT)
|
|
get_timewait4_sock(v, seq, st->num);
|
|
else if (sk->sk_state == TCP_NEW_SYN_RECV)
|
|
get_openreq4(v, seq, st->num);
|
|
else
|
|
get_tcp4_sock(v, seq, st->num);
|
|
out:
|
|
seq_pad(seq, '\n');
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations tcp4_seq_ops = {
|
|
.show = tcp4_seq_show,
|
|
.start = tcp_seq_start,
|
|
.next = tcp_seq_next,
|
|
.stop = tcp_seq_stop,
|
|
};
|
|
|
|
static struct tcp_seq_afinfo tcp4_seq_afinfo = {
|
|
.family = AF_INET,
|
|
};
|
|
|
|
static int __net_init tcp4_proc_init_net(struct net *net)
|
|
{
|
|
if (!proc_create_net_data("tcp", 0444, net->proc_net, &tcp4_seq_ops,
|
|
sizeof(struct tcp_iter_state), &tcp4_seq_afinfo))
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
static void __net_exit tcp4_proc_exit_net(struct net *net)
|
|
{
|
|
remove_proc_entry("tcp", net->proc_net);
|
|
}
|
|
|
|
static struct pernet_operations tcp4_net_ops = {
|
|
.init = tcp4_proc_init_net,
|
|
.exit = tcp4_proc_exit_net,
|
|
};
|
|
|
|
int __init tcp4_proc_init(void)
|
|
{
|
|
return register_pernet_subsys(&tcp4_net_ops);
|
|
}
|
|
|
|
void tcp4_proc_exit(void)
|
|
{
|
|
unregister_pernet_subsys(&tcp4_net_ops);
|
|
}
|
|
#endif /* CONFIG_PROC_FS */
|
|
|
|
struct proto tcp_prot = {
|
|
.name = "TCP",
|
|
.owner = THIS_MODULE,
|
|
.close = tcp_close,
|
|
.pre_connect = tcp_v4_pre_connect,
|
|
.connect = tcp_v4_connect,
|
|
.disconnect = tcp_disconnect,
|
|
.accept = inet_csk_accept,
|
|
.ioctl = tcp_ioctl,
|
|
.init = tcp_v4_init_sock,
|
|
.destroy = tcp_v4_destroy_sock,
|
|
.shutdown = tcp_shutdown,
|
|
.setsockopt = tcp_setsockopt,
|
|
.getsockopt = tcp_getsockopt,
|
|
.keepalive = tcp_set_keepalive,
|
|
.recvmsg = tcp_recvmsg,
|
|
.sendmsg = tcp_sendmsg,
|
|
.sendpage = tcp_sendpage,
|
|
.backlog_rcv = tcp_v4_do_rcv,
|
|
.release_cb = tcp_release_cb,
|
|
.hash = inet_hash,
|
|
.unhash = inet_unhash,
|
|
.get_port = inet_csk_get_port,
|
|
.enter_memory_pressure = tcp_enter_memory_pressure,
|
|
.leave_memory_pressure = tcp_leave_memory_pressure,
|
|
.stream_memory_free = tcp_stream_memory_free,
|
|
.sockets_allocated = &tcp_sockets_allocated,
|
|
.orphan_count = &tcp_orphan_count,
|
|
.memory_allocated = &tcp_memory_allocated,
|
|
.memory_pressure = &tcp_memory_pressure,
|
|
.sysctl_mem = sysctl_tcp_mem,
|
|
.sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_tcp_wmem),
|
|
.sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_tcp_rmem),
|
|
.max_header = MAX_TCP_HEADER,
|
|
.obj_size = sizeof(struct tcp_sock),
|
|
.slab_flags = SLAB_TYPESAFE_BY_RCU,
|
|
.twsk_prot = &tcp_timewait_sock_ops,
|
|
.rsk_prot = &tcp_request_sock_ops,
|
|
.h.hashinfo = &tcp_hashinfo,
|
|
.no_autobind = true,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_setsockopt = compat_tcp_setsockopt,
|
|
.compat_getsockopt = compat_tcp_getsockopt,
|
|
#endif
|
|
.diag_destroy = tcp_abort,
|
|
};
|
|
EXPORT_SYMBOL(tcp_prot);
|
|
|
|
static void __net_exit tcp_sk_exit(struct net *net)
|
|
{
|
|
int cpu;
|
|
|
|
if (net->ipv4.tcp_congestion_control)
|
|
module_put(net->ipv4.tcp_congestion_control->owner);
|
|
|
|
for_each_possible_cpu(cpu)
|
|
inet_ctl_sock_destroy(*per_cpu_ptr(net->ipv4.tcp_sk, cpu));
|
|
free_percpu(net->ipv4.tcp_sk);
|
|
}
|
|
|
|
static int __net_init tcp_sk_init(struct net *net)
|
|
{
|
|
int res, cpu, cnt;
|
|
|
|
net->ipv4.tcp_sk = alloc_percpu(struct sock *);
|
|
if (!net->ipv4.tcp_sk)
|
|
return -ENOMEM;
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
struct sock *sk;
|
|
|
|
res = inet_ctl_sock_create(&sk, PF_INET, SOCK_RAW,
|
|
IPPROTO_TCP, net);
|
|
if (res)
|
|
goto fail;
|
|
sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
|
|
|
|
/* Please enforce IP_DF and IPID==0 for RST and
|
|
* ACK sent in SYN-RECV and TIME-WAIT state.
|
|
*/
|
|
inet_sk(sk)->pmtudisc = IP_PMTUDISC_DO;
|
|
|
|
*per_cpu_ptr(net->ipv4.tcp_sk, cpu) = sk;
|
|
}
|
|
|
|
net->ipv4.sysctl_tcp_ecn = 2;
|
|
net->ipv4.sysctl_tcp_ecn_fallback = 1;
|
|
|
|
net->ipv4.sysctl_tcp_base_mss = TCP_BASE_MSS;
|
|
net->ipv4.sysctl_tcp_min_snd_mss = TCP_MIN_SND_MSS;
|
|
net->ipv4.sysctl_tcp_probe_threshold = TCP_PROBE_THRESHOLD;
|
|
net->ipv4.sysctl_tcp_probe_interval = TCP_PROBE_INTERVAL;
|
|
|
|
net->ipv4.sysctl_tcp_keepalive_time = TCP_KEEPALIVE_TIME;
|
|
net->ipv4.sysctl_tcp_keepalive_probes = TCP_KEEPALIVE_PROBES;
|
|
net->ipv4.sysctl_tcp_keepalive_intvl = TCP_KEEPALIVE_INTVL;
|
|
|
|
net->ipv4.sysctl_tcp_syn_retries = TCP_SYN_RETRIES;
|
|
net->ipv4.sysctl_tcp_synack_retries = TCP_SYNACK_RETRIES;
|
|
net->ipv4.sysctl_tcp_syncookies = 1;
|
|
net->ipv4.sysctl_tcp_reordering = TCP_FASTRETRANS_THRESH;
|
|
net->ipv4.sysctl_tcp_retries1 = TCP_RETR1;
|
|
net->ipv4.sysctl_tcp_retries2 = TCP_RETR2;
|
|
net->ipv4.sysctl_tcp_orphan_retries = 0;
|
|
net->ipv4.sysctl_tcp_fin_timeout = TCP_FIN_TIMEOUT;
|
|
net->ipv4.sysctl_tcp_notsent_lowat = UINT_MAX;
|
|
net->ipv4.sysctl_tcp_tw_reuse = 2;
|
|
|
|
cnt = tcp_hashinfo.ehash_mask + 1;
|
|
net->ipv4.tcp_death_row.sysctl_max_tw_buckets = cnt / 2;
|
|
net->ipv4.tcp_death_row.hashinfo = &tcp_hashinfo;
|
|
|
|
net->ipv4.sysctl_max_syn_backlog = max(128, cnt / 256);
|
|
net->ipv4.sysctl_tcp_sack = 1;
|
|
net->ipv4.sysctl_tcp_window_scaling = 1;
|
|
net->ipv4.sysctl_tcp_timestamps = 1;
|
|
net->ipv4.sysctl_tcp_early_retrans = 3;
|
|
net->ipv4.sysctl_tcp_recovery = TCP_RACK_LOSS_DETECTION;
|
|
net->ipv4.sysctl_tcp_slow_start_after_idle = 1; /* By default, RFC2861 behavior. */
|
|
net->ipv4.sysctl_tcp_retrans_collapse = 1;
|
|
net->ipv4.sysctl_tcp_max_reordering = 300;
|
|
net->ipv4.sysctl_tcp_dsack = 1;
|
|
net->ipv4.sysctl_tcp_app_win = 31;
|
|
net->ipv4.sysctl_tcp_adv_win_scale = 1;
|
|
net->ipv4.sysctl_tcp_frto = 2;
|
|
net->ipv4.sysctl_tcp_moderate_rcvbuf = 1;
|
|
/* This limits the percentage of the congestion window which we
|
|
* will allow a single TSO frame to consume. Building TSO frames
|
|
* which are too large can cause TCP streams to be bursty.
|
|
*/
|
|
net->ipv4.sysctl_tcp_tso_win_divisor = 3;
|
|
/* Default TSQ limit of 16 TSO segments */
|
|
net->ipv4.sysctl_tcp_limit_output_bytes = 16 * 65536;
|
|
/* rfc5961 challenge ack rate limiting */
|
|
net->ipv4.sysctl_tcp_challenge_ack_limit = 1000;
|
|
net->ipv4.sysctl_tcp_min_tso_segs = 2;
|
|
net->ipv4.sysctl_tcp_min_rtt_wlen = 300;
|
|
net->ipv4.sysctl_tcp_autocorking = 1;
|
|
net->ipv4.sysctl_tcp_invalid_ratelimit = HZ/2;
|
|
net->ipv4.sysctl_tcp_pacing_ss_ratio = 200;
|
|
net->ipv4.sysctl_tcp_pacing_ca_ratio = 120;
|
|
if (net != &init_net) {
|
|
memcpy(net->ipv4.sysctl_tcp_rmem,
|
|
init_net.ipv4.sysctl_tcp_rmem,
|
|
sizeof(init_net.ipv4.sysctl_tcp_rmem));
|
|
memcpy(net->ipv4.sysctl_tcp_wmem,
|
|
init_net.ipv4.sysctl_tcp_wmem,
|
|
sizeof(init_net.ipv4.sysctl_tcp_wmem));
|
|
}
|
|
net->ipv4.sysctl_tcp_comp_sack_delay_ns = NSEC_PER_MSEC;
|
|
net->ipv4.sysctl_tcp_comp_sack_nr = 44;
|
|
net->ipv4.sysctl_tcp_fastopen = TFO_CLIENT_ENABLE;
|
|
spin_lock_init(&net->ipv4.tcp_fastopen_ctx_lock);
|
|
net->ipv4.sysctl_tcp_fastopen_blackhole_timeout = 60 * 60;
|
|
atomic_set(&net->ipv4.tfo_active_disable_times, 0);
|
|
|
|
/* Reno is always built in */
|
|
if (!net_eq(net, &init_net) &&
|
|
try_module_get(init_net.ipv4.tcp_congestion_control->owner))
|
|
net->ipv4.tcp_congestion_control = init_net.ipv4.tcp_congestion_control;
|
|
else
|
|
net->ipv4.tcp_congestion_control = &tcp_reno;
|
|
|
|
return 0;
|
|
fail:
|
|
tcp_sk_exit(net);
|
|
|
|
return res;
|
|
}
|
|
|
|
static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list)
|
|
{
|
|
struct net *net;
|
|
|
|
inet_twsk_purge(&tcp_hashinfo, AF_INET);
|
|
|
|
list_for_each_entry(net, net_exit_list, exit_list)
|
|
tcp_fastopen_ctx_destroy(net);
|
|
}
|
|
|
|
static struct pernet_operations __net_initdata tcp_sk_ops = {
|
|
.init = tcp_sk_init,
|
|
.exit = tcp_sk_exit,
|
|
.exit_batch = tcp_sk_exit_batch,
|
|
};
|
|
|
|
void __init tcp_v4_init(void)
|
|
{
|
|
if (register_pernet_subsys(&tcp_sk_ops))
|
|
panic("Failed to create the TCP control socket.\n");
|
|
}
|