1358 lines
35 KiB
C
1358 lines
35 KiB
C
/*
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* net/dccp/ipv4.c
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*
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* An implementation of the DCCP protocol
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* Arnaldo Carvalho de Melo <acme@conectiva.com.br>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/config.h>
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#include <linux/dccp.h>
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#include <linux/icmp.h>
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#include <linux/module.h>
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#include <linux/skbuff.h>
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#include <linux/random.h>
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#include <net/icmp.h>
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#include <net/inet_hashtables.h>
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#include <net/sock.h>
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#include <net/tcp_states.h>
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#include <net/xfrm.h>
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#include "ccid.h"
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#include "dccp.h"
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struct inet_hashinfo __cacheline_aligned dccp_hashinfo = {
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.lhash_lock = RW_LOCK_UNLOCKED,
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.lhash_users = ATOMIC_INIT(0),
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.lhash_wait = __WAIT_QUEUE_HEAD_INITIALIZER(dccp_hashinfo.lhash_wait),
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.portalloc_lock = SPIN_LOCK_UNLOCKED,
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.port_rover = 1024 - 1,
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};
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EXPORT_SYMBOL_GPL(dccp_hashinfo);
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static int dccp_v4_get_port(struct sock *sk, const unsigned short snum)
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{
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return inet_csk_get_port(&dccp_hashinfo, sk, snum);
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}
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static void dccp_v4_hash(struct sock *sk)
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{
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inet_hash(&dccp_hashinfo, sk);
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}
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static void dccp_v4_unhash(struct sock *sk)
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{
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inet_unhash(&dccp_hashinfo, sk);
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}
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/* called with local bh disabled */
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static int __dccp_v4_check_established(struct sock *sk, const __u16 lport,
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struct inet_timewait_sock **twp)
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{
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struct inet_sock *inet = inet_sk(sk);
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const u32 daddr = inet->rcv_saddr;
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const u32 saddr = inet->daddr;
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const int dif = sk->sk_bound_dev_if;
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INET_ADDR_COOKIE(acookie, saddr, daddr)
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const __u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
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const int hash = inet_ehashfn(daddr, lport, saddr, inet->dport,
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dccp_hashinfo.ehash_size);
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struct inet_ehash_bucket *head = &dccp_hashinfo.ehash[hash];
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const struct sock *sk2;
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const struct hlist_node *node;
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struct inet_timewait_sock *tw;
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write_lock(&head->lock);
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/* Check TIME-WAIT sockets first. */
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sk_for_each(sk2, node, &(head + dccp_hashinfo.ehash_size)->chain) {
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tw = inet_twsk(sk2);
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if (INET_TW_MATCH(sk2, acookie, saddr, daddr, ports, dif))
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goto not_unique;
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}
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tw = NULL;
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/* And established part... */
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sk_for_each(sk2, node, &head->chain) {
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if (INET_MATCH(sk2, acookie, saddr, daddr, ports, dif))
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goto not_unique;
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}
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/* Must record num and sport now. Otherwise we will see
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* in hash table socket with a funny identity. */
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inet->num = lport;
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inet->sport = htons(lport);
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sk->sk_hashent = hash;
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BUG_TRAP(sk_unhashed(sk));
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__sk_add_node(sk, &head->chain);
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sock_prot_inc_use(sk->sk_prot);
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write_unlock(&head->lock);
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if (twp != NULL) {
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*twp = tw;
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NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
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} else if (tw != NULL) {
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/* Silly. Should hash-dance instead... */
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inet_twsk_deschedule(tw, &dccp_death_row);
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NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
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inet_twsk_put(tw);
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}
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return 0;
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not_unique:
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write_unlock(&head->lock);
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return -EADDRNOTAVAIL;
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}
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/*
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* Bind a port for a connect operation and hash it.
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*/
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static int dccp_v4_hash_connect(struct sock *sk)
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{
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const unsigned short snum = inet_sk(sk)->num;
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struct inet_bind_hashbucket *head;
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struct inet_bind_bucket *tb;
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int ret;
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if (snum == 0) {
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int rover;
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int low = sysctl_local_port_range[0];
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int high = sysctl_local_port_range[1];
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int remaining = (high - low) + 1;
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struct hlist_node *node;
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struct inet_timewait_sock *tw = NULL;
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local_bh_disable();
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/* TODO. Actually it is not so bad idea to remove
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* dccp_hashinfo.portalloc_lock before next submission to
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* Linus.
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* As soon as we touch this place at all it is time to think.
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*
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* Now it protects single _advisory_ variable
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* dccp_hashinfo.port_rover, hence it is mostly useless.
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* Code will work nicely if we just delete it, but
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* I am afraid in contented case it will work not better or
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* even worse: another cpu just will hit the same bucket
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* and spin there.
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* So some cpu salt could remove both contention and
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* memory pingpong. Any ideas how to do this in a nice way?
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*/
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spin_lock(&dccp_hashinfo.portalloc_lock);
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rover = dccp_hashinfo.port_rover;
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do {
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rover++;
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if ((rover < low) || (rover > high))
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rover = low;
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head = &dccp_hashinfo.bhash[inet_bhashfn(rover,
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dccp_hashinfo.bhash_size)];
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spin_lock(&head->lock);
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/* Does not bother with rcv_saddr checks,
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* because the established check is already
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* unique enough.
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*/
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inet_bind_bucket_for_each(tb, node, &head->chain) {
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if (tb->port == rover) {
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BUG_TRAP(!hlist_empty(&tb->owners));
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if (tb->fastreuse >= 0)
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goto next_port;
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if (!__dccp_v4_check_established(sk,
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rover,
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&tw))
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goto ok;
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goto next_port;
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}
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}
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tb = inet_bind_bucket_create(dccp_hashinfo.bind_bucket_cachep,
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head, rover);
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if (tb == NULL) {
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spin_unlock(&head->lock);
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break;
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}
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tb->fastreuse = -1;
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goto ok;
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next_port:
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spin_unlock(&head->lock);
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} while (--remaining > 0);
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dccp_hashinfo.port_rover = rover;
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spin_unlock(&dccp_hashinfo.portalloc_lock);
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local_bh_enable();
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return -EADDRNOTAVAIL;
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ok:
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/* All locks still held and bhs disabled */
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dccp_hashinfo.port_rover = rover;
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spin_unlock(&dccp_hashinfo.portalloc_lock);
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inet_bind_hash(sk, tb, rover);
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if (sk_unhashed(sk)) {
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inet_sk(sk)->sport = htons(rover);
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__inet_hash(&dccp_hashinfo, sk, 0);
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}
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spin_unlock(&head->lock);
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if (tw != NULL) {
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inet_twsk_deschedule(tw, &dccp_death_row);
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inet_twsk_put(tw);
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}
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ret = 0;
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goto out;
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}
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head = &dccp_hashinfo.bhash[inet_bhashfn(snum,
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dccp_hashinfo.bhash_size)];
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tb = inet_csk(sk)->icsk_bind_hash;
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spin_lock_bh(&head->lock);
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if (sk_head(&tb->owners) == sk && sk->sk_bind_node.next == NULL) {
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__inet_hash(&dccp_hashinfo, sk, 0);
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spin_unlock_bh(&head->lock);
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return 0;
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} else {
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spin_unlock(&head->lock);
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/* No definite answer... Walk to established hash table */
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ret = __dccp_v4_check_established(sk, snum, NULL);
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out:
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local_bh_enable();
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return ret;
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}
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}
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static int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr,
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int addr_len)
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{
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struct inet_sock *inet = inet_sk(sk);
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struct dccp_sock *dp = dccp_sk(sk);
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const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr;
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struct rtable *rt;
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u32 daddr, nexthop;
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int tmp;
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int err;
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dp->dccps_role = DCCP_ROLE_CLIENT;
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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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if (inet->opt != NULL && inet->opt->srr) {
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if (daddr == 0)
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return -EINVAL;
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nexthop = inet->opt->faddr;
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}
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tmp = ip_route_connect(&rt, nexthop, inet->saddr,
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RT_CONN_FLAGS(sk), sk->sk_bound_dev_if,
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IPPROTO_DCCP,
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inet->sport, usin->sin_port, sk);
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if (tmp < 0)
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return tmp;
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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 == NULL || !inet->opt->srr)
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daddr = rt->rt_dst;
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if (inet->saddr == 0)
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inet->saddr = rt->rt_src;
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inet->rcv_saddr = inet->saddr;
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inet->dport = usin->sin_port;
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inet->daddr = daddr;
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dp->dccps_ext_header_len = 0;
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if (inet->opt != NULL)
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dp->dccps_ext_header_len = inet->opt->optlen;
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/*
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* Socket identity is still unknown (sport may be zero).
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* However we set state to DCCP_REQUESTING 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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dccp_set_state(sk, DCCP_REQUESTING);
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err = dccp_v4_hash_connect(sk);
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if (err != 0)
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goto failure;
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err = ip_route_newports(&rt, inet->sport, inet->dport, sk);
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if (err != 0)
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goto failure;
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/* OK, now commit destination to socket. */
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sk_setup_caps(sk, &rt->u.dst);
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dp->dccps_gar =
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dp->dccps_iss = secure_dccp_sequence_number(inet->saddr,
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inet->daddr,
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inet->sport,
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usin->sin_port);
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dccp_update_gss(sk, dp->dccps_iss);
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/*
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* SWL and AWL are initially adjusted so that they are not less than
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* the initial Sequence Numbers received and sent, respectively:
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* SWL := max(GSR + 1 - floor(W/4), ISR),
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* AWL := max(GSS - W' + 1, ISS).
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* These adjustments MUST be applied only at the beginning of the
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* connection.
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*/
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dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss));
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inet->id = dp->dccps_iss ^ jiffies;
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err = dccp_connect(sk);
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rt = NULL;
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if (err != 0)
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goto failure;
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out:
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return err;
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failure:
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/*
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* This unhashes the socket and releases the local port, if necessary.
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*/
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dccp_set_state(sk, DCCP_CLOSED);
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ip_rt_put(rt);
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sk->sk_route_caps = 0;
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inet->dport = 0;
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goto out;
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}
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/*
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* This routine does path mtu discovery as defined in RFC1191.
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*/
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static inline void dccp_do_pmtu_discovery(struct sock *sk,
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const struct iphdr *iph,
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u32 mtu)
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{
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struct dst_entry *dst;
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const struct inet_sock *inet = inet_sk(sk);
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const struct dccp_sock *dp = dccp_sk(sk);
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/* We are not interested in DCCP_LISTEN and request_socks (RESPONSEs
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* send out by Linux are always < 576bytes so they should go through
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* unfragmented).
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*/
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if (sk->sk_state == DCCP_LISTEN)
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return;
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|
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/* We don't check in the destentry if pmtu discovery is forbidden
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* on this route. We just assume that no packet_to_big packets
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* are send back when pmtu discovery is not active.
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* There is a small race when the user changes this flag in the
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* route, but I think that's acceptable.
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*/
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if ((dst = __sk_dst_check(sk, 0)) == NULL)
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return;
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dst->ops->update_pmtu(dst, mtu);
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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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if (inet->pmtudisc != IP_PMTUDISC_DONT &&
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dp->dccps_pmtu_cookie > mtu) {
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dccp_sync_mss(sk, mtu);
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|
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/*
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* From: draft-ietf-dccp-spec-11.txt
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*
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* DCCP-Sync packets are the best choice for upward
|
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* probing, since DCCP-Sync probes do not risk application
|
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* data loss.
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*/
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dccp_send_sync(sk, dp->dccps_gsr, DCCP_PKT_SYNC);
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} /* else let the usual retransmit timer handle it */
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}
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static void dccp_v4_ctl_send_ack(struct sk_buff *rxskb)
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{
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int err;
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struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
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const int dccp_hdr_ack_len = sizeof(struct dccp_hdr) +
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sizeof(struct dccp_hdr_ext) +
|
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sizeof(struct dccp_hdr_ack_bits);
|
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struct sk_buff *skb;
|
|
|
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if (((struct rtable *)rxskb->dst)->rt_type != RTN_LOCAL)
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return;
|
|
|
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skb = alloc_skb(MAX_DCCP_HEADER + 15, GFP_ATOMIC);
|
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if (skb == NULL)
|
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return;
|
|
|
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/* Reserve space for headers. */
|
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skb_reserve(skb, MAX_DCCP_HEADER);
|
|
|
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skb->dst = dst_clone(rxskb->dst);
|
|
|
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skb->h.raw = skb_push(skb, dccp_hdr_ack_len);
|
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dh = dccp_hdr(skb);
|
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memset(dh, 0, dccp_hdr_ack_len);
|
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|
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/* Build DCCP header and checksum it. */
|
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dh->dccph_type = DCCP_PKT_ACK;
|
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dh->dccph_sport = rxdh->dccph_dport;
|
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dh->dccph_dport = rxdh->dccph_sport;
|
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dh->dccph_doff = dccp_hdr_ack_len / 4;
|
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dh->dccph_x = 1;
|
|
|
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dccp_hdr_set_seq(dh, DCCP_SKB_CB(rxskb)->dccpd_ack_seq);
|
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dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
|
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DCCP_SKB_CB(rxskb)->dccpd_seq);
|
|
|
|
bh_lock_sock(dccp_ctl_socket->sk);
|
|
err = ip_build_and_send_pkt(skb, dccp_ctl_socket->sk,
|
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rxskb->nh.iph->daddr,
|
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rxskb->nh.iph->saddr, NULL);
|
|
bh_unlock_sock(dccp_ctl_socket->sk);
|
|
|
|
if (err == NET_XMIT_CN || err == 0) {
|
|
DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
|
|
DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
|
|
}
|
|
}
|
|
|
|
static void dccp_v4_reqsk_send_ack(struct sk_buff *skb,
|
|
struct request_sock *req)
|
|
{
|
|
dccp_v4_ctl_send_ack(skb);
|
|
}
|
|
|
|
static int dccp_v4_send_response(struct sock *sk, struct request_sock *req,
|
|
struct dst_entry *dst)
|
|
{
|
|
int err = -1;
|
|
struct sk_buff *skb;
|
|
|
|
/* First, grab a route. */
|
|
|
|
if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL)
|
|
goto out;
|
|
|
|
skb = dccp_make_response(sk, dst, req);
|
|
if (skb != NULL) {
|
|
const struct inet_request_sock *ireq = inet_rsk(req);
|
|
|
|
err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr,
|
|
ireq->rmt_addr,
|
|
ireq->opt);
|
|
if (err == NET_XMIT_CN)
|
|
err = 0;
|
|
}
|
|
|
|
out:
|
|
dst_release(dst);
|
|
return 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.
|
|
*/
|
|
void dccp_v4_err(struct sk_buff *skb, u32 info)
|
|
{
|
|
const struct iphdr *iph = (struct iphdr *)skb->data;
|
|
const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data +
|
|
(iph->ihl << 2));
|
|
struct dccp_sock *dp;
|
|
struct inet_sock *inet;
|
|
const int type = skb->h.icmph->type;
|
|
const int code = skb->h.icmph->code;
|
|
struct sock *sk;
|
|
__u64 seq;
|
|
int err;
|
|
|
|
if (skb->len < (iph->ihl << 2) + 8) {
|
|
ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
|
|
return;
|
|
}
|
|
|
|
sk = inet_lookup(&dccp_hashinfo, iph->daddr, dh->dccph_dport,
|
|
iph->saddr, dh->dccph_sport, inet_iif(skb));
|
|
if (sk == NULL) {
|
|
ICMP_INC_STATS_BH(ICMP_MIB_INERRORS);
|
|
return;
|
|
}
|
|
|
|
if (sk->sk_state == DCCP_TIME_WAIT) {
|
|
inet_twsk_put((struct inet_timewait_sock *)sk);
|
|
return;
|
|
}
|
|
|
|
bh_lock_sock(sk);
|
|
/* If too many ICMPs get dropped on busy
|
|
* servers this needs to be solved differently.
|
|
*/
|
|
if (sock_owned_by_user(sk))
|
|
NET_INC_STATS_BH(LINUX_MIB_LOCKDROPPEDICMPS);
|
|
|
|
if (sk->sk_state == DCCP_CLOSED)
|
|
goto out;
|
|
|
|
dp = dccp_sk(sk);
|
|
seq = dccp_hdr_seq(skb);
|
|
if (sk->sk_state != DCCP_LISTEN &&
|
|
!between48(seq, dp->dccps_swl, dp->dccps_swh)) {
|
|
NET_INC_STATS(LINUX_MIB_OUTOFWINDOWICMPS);
|
|
goto out;
|
|
}
|
|
|
|
switch (type) {
|
|
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) */
|
|
if (!sock_owned_by_user(sk))
|
|
dccp_do_pmtu_discovery(sk, iph, info);
|
|
goto out;
|
|
}
|
|
|
|
err = icmp_err_convert[code].errno;
|
|
break;
|
|
case ICMP_TIME_EXCEEDED:
|
|
err = EHOSTUNREACH;
|
|
break;
|
|
default:
|
|
goto out;
|
|
}
|
|
|
|
switch (sk->sk_state) {
|
|
struct request_sock *req , **prev;
|
|
case DCCP_LISTEN:
|
|
if (sock_owned_by_user(sk))
|
|
goto out;
|
|
req = inet_csk_search_req(sk, &prev, dh->dccph_dport,
|
|
iph->daddr, iph->saddr);
|
|
if (!req)
|
|
goto out;
|
|
|
|
/*
|
|
* ICMPs are not backlogged, hence we cannot get an established
|
|
* socket here.
|
|
*/
|
|
BUG_TRAP(!req->sk);
|
|
|
|
if (seq != dccp_rsk(req)->dreq_iss) {
|
|
NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
|
|
goto out;
|
|
}
|
|
/*
|
|
* Still in RESPOND, 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(sk, req, prev);
|
|
goto out;
|
|
|
|
case DCCP_REQUESTING:
|
|
case DCCP_RESPOND:
|
|
if (!sock_owned_by_user(sk)) {
|
|
DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
|
|
sk->sk_err = err;
|
|
|
|
sk->sk_error_report(sk);
|
|
|
|
dccp_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);
|
|
}
|
|
|
|
int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code)
|
|
{
|
|
struct sk_buff *skb;
|
|
/*
|
|
* FIXME: what if rebuild_header fails?
|
|
* Should we be doing a rebuild_header here?
|
|
*/
|
|
int err = inet_sk_rebuild_header(sk);
|
|
|
|
if (err != 0)
|
|
return err;
|
|
|
|
skb = dccp_make_reset(sk, sk->sk_dst_cache, code);
|
|
if (skb != NULL) {
|
|
const struct inet_sock *inet = inet_sk(sk);
|
|
|
|
err = ip_build_and_send_pkt(skb, sk,
|
|
inet->saddr, inet->daddr, NULL);
|
|
if (err == NET_XMIT_CN)
|
|
err = 0;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static inline u64 dccp_v4_init_sequence(const struct sock *sk,
|
|
const struct sk_buff *skb)
|
|
{
|
|
return secure_dccp_sequence_number(skb->nh.iph->daddr,
|
|
skb->nh.iph->saddr,
|
|
dccp_hdr(skb)->dccph_dport,
|
|
dccp_hdr(skb)->dccph_sport);
|
|
}
|
|
|
|
int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct inet_request_sock *ireq;
|
|
struct dccp_sock dp;
|
|
struct request_sock *req;
|
|
struct dccp_request_sock *dreq;
|
|
const __u32 saddr = skb->nh.iph->saddr;
|
|
const __u32 daddr = skb->nh.iph->daddr;
|
|
struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
|
|
__u8 reset_code = DCCP_RESET_CODE_TOO_BUSY;
|
|
struct dst_entry *dst = NULL;
|
|
|
|
/* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */
|
|
if (((struct rtable *)skb->dst)->rt_flags &
|
|
(RTCF_BROADCAST | RTCF_MULTICAST)) {
|
|
reset_code = DCCP_RESET_CODE_NO_CONNECTION;
|
|
goto drop;
|
|
}
|
|
|
|
/*
|
|
* TW buckets are converted to open requests without
|
|
* limitations, they conserve resources and peer is
|
|
* evidently real one.
|
|
*/
|
|
if (inet_csk_reqsk_queue_is_full(sk))
|
|
goto drop;
|
|
|
|
/*
|
|
* Accept backlog is full. If we have already queued enough
|
|
* of warm entries in syn queue, drop request. It is better than
|
|
* clogging syn queue with openreqs with exponentially increasing
|
|
* timeout.
|
|
*/
|
|
if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
|
|
goto drop;
|
|
|
|
req = reqsk_alloc(sk->sk_prot->rsk_prot);
|
|
if (req == NULL)
|
|
goto drop;
|
|
|
|
/* FIXME: process options */
|
|
|
|
dccp_openreq_init(req, &dp, skb);
|
|
|
|
ireq = inet_rsk(req);
|
|
ireq->loc_addr = daddr;
|
|
ireq->rmt_addr = saddr;
|
|
/* FIXME: Merge Aristeu's option parsing code when ready */
|
|
req->rcv_wnd = 100; /* Fake, option parsing will get the
|
|
right value */
|
|
ireq->opt = NULL;
|
|
|
|
/*
|
|
* Step 3: Process LISTEN state
|
|
*
|
|
* Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
|
|
*
|
|
* In fact we defer setting S.GSR, S.SWL, S.SWH to
|
|
* dccp_create_openreq_child.
|
|
*/
|
|
dreq = dccp_rsk(req);
|
|
dreq->dreq_isr = dcb->dccpd_seq;
|
|
dreq->dreq_iss = dccp_v4_init_sequence(sk, skb);
|
|
dreq->dreq_service = dccp_hdr_request(skb)->dccph_req_service;
|
|
|
|
if (dccp_v4_send_response(sk, req, dst))
|
|
goto drop_and_free;
|
|
|
|
inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
|
|
return 0;
|
|
|
|
drop_and_free:
|
|
/*
|
|
* FIXME: should be reqsk_free after implementing req->rsk_ops
|
|
*/
|
|
__reqsk_free(req);
|
|
drop:
|
|
DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
|
|
dcb->dccpd_reset_code = reset_code;
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* The three way handshake has completed - we got a valid ACK or DATAACK -
|
|
* now create the new socket.
|
|
*
|
|
* This is the equivalent of TCP's tcp_v4_syn_recv_sock
|
|
*/
|
|
struct sock *dccp_v4_request_recv_sock(struct sock *sk, struct sk_buff *skb,
|
|
struct request_sock *req,
|
|
struct dst_entry *dst)
|
|
{
|
|
struct inet_request_sock *ireq;
|
|
struct inet_sock *newinet;
|
|
struct dccp_sock *newdp;
|
|
struct sock *newsk;
|
|
|
|
if (sk_acceptq_is_full(sk))
|
|
goto exit_overflow;
|
|
|
|
if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL)
|
|
goto exit;
|
|
|
|
newsk = dccp_create_openreq_child(sk, req, skb);
|
|
if (newsk == NULL)
|
|
goto exit;
|
|
|
|
sk_setup_caps(newsk, dst);
|
|
|
|
newdp = dccp_sk(newsk);
|
|
newinet = inet_sk(newsk);
|
|
ireq = inet_rsk(req);
|
|
newinet->daddr = ireq->rmt_addr;
|
|
newinet->rcv_saddr = ireq->loc_addr;
|
|
newinet->saddr = ireq->loc_addr;
|
|
newinet->opt = ireq->opt;
|
|
ireq->opt = NULL;
|
|
newinet->mc_index = inet_iif(skb);
|
|
newinet->mc_ttl = skb->nh.iph->ttl;
|
|
newinet->id = jiffies;
|
|
|
|
dccp_sync_mss(newsk, dst_mtu(dst));
|
|
|
|
__inet_hash(&dccp_hashinfo, newsk, 0);
|
|
__inet_inherit_port(&dccp_hashinfo, sk, newsk);
|
|
|
|
return newsk;
|
|
|
|
exit_overflow:
|
|
NET_INC_STATS_BH(LINUX_MIB_LISTENOVERFLOWS);
|
|
exit:
|
|
NET_INC_STATS_BH(LINUX_MIB_LISTENDROPS);
|
|
dst_release(dst);
|
|
return NULL;
|
|
}
|
|
|
|
static struct sock *dccp_v4_hnd_req(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
const struct dccp_hdr *dh = dccp_hdr(skb);
|
|
const struct iphdr *iph = skb->nh.iph;
|
|
struct sock *nsk;
|
|
struct request_sock **prev;
|
|
/* Find possible connection requests. */
|
|
struct request_sock *req = inet_csk_search_req(sk, &prev,
|
|
dh->dccph_sport,
|
|
iph->saddr, iph->daddr);
|
|
if (req != NULL)
|
|
return dccp_check_req(sk, skb, req, prev);
|
|
|
|
nsk = __inet_lookup_established(&dccp_hashinfo,
|
|
iph->saddr, dh->dccph_sport,
|
|
iph->daddr, ntohs(dh->dccph_dport),
|
|
inet_iif(skb));
|
|
if (nsk != NULL) {
|
|
if (nsk->sk_state != DCCP_TIME_WAIT) {
|
|
bh_lock_sock(nsk);
|
|
return nsk;
|
|
}
|
|
inet_twsk_put((struct inet_timewait_sock *)nsk);
|
|
return NULL;
|
|
}
|
|
|
|
return sk;
|
|
}
|
|
|
|
int dccp_v4_checksum(const struct sk_buff *skb, const u32 saddr,
|
|
const u32 daddr)
|
|
{
|
|
const struct dccp_hdr* dh = dccp_hdr(skb);
|
|
int checksum_len;
|
|
u32 tmp;
|
|
|
|
if (dh->dccph_cscov == 0)
|
|
checksum_len = skb->len;
|
|
else {
|
|
checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32);
|
|
checksum_len = checksum_len < skb->len ? checksum_len :
|
|
skb->len;
|
|
}
|
|
|
|
tmp = csum_partial((unsigned char *)dh, checksum_len, 0);
|
|
return csum_tcpudp_magic(saddr, daddr, checksum_len,
|
|
IPPROTO_DCCP, tmp);
|
|
}
|
|
|
|
static int dccp_v4_verify_checksum(struct sk_buff *skb,
|
|
const u32 saddr, const u32 daddr)
|
|
{
|
|
struct dccp_hdr *dh = dccp_hdr(skb);
|
|
int checksum_len;
|
|
u32 tmp;
|
|
|
|
if (dh->dccph_cscov == 0)
|
|
checksum_len = skb->len;
|
|
else {
|
|
checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32);
|
|
checksum_len = checksum_len < skb->len ? checksum_len :
|
|
skb->len;
|
|
}
|
|
tmp = csum_partial((unsigned char *)dh, checksum_len, 0);
|
|
return csum_tcpudp_magic(saddr, daddr, checksum_len,
|
|
IPPROTO_DCCP, tmp) == 0 ? 0 : -1;
|
|
}
|
|
|
|
static struct dst_entry* dccp_v4_route_skb(struct sock *sk,
|
|
struct sk_buff *skb)
|
|
{
|
|
struct rtable *rt;
|
|
struct flowi fl = { .oif = ((struct rtable *)skb->dst)->rt_iif,
|
|
.nl_u = { .ip4_u =
|
|
{ .daddr = skb->nh.iph->saddr,
|
|
.saddr = skb->nh.iph->daddr,
|
|
.tos = RT_CONN_FLAGS(sk) } },
|
|
.proto = sk->sk_protocol,
|
|
.uli_u = { .ports =
|
|
{ .sport = dccp_hdr(skb)->dccph_dport,
|
|
.dport = dccp_hdr(skb)->dccph_sport }
|
|
}
|
|
};
|
|
|
|
if (ip_route_output_flow(&rt, &fl, sk, 0)) {
|
|
IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
|
|
return NULL;
|
|
}
|
|
|
|
return &rt->u.dst;
|
|
}
|
|
|
|
static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb)
|
|
{
|
|
int err;
|
|
struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
|
|
const int dccp_hdr_reset_len = sizeof(struct dccp_hdr) +
|
|
sizeof(struct dccp_hdr_ext) +
|
|
sizeof(struct dccp_hdr_reset);
|
|
struct sk_buff *skb;
|
|
struct dst_entry *dst;
|
|
u64 seqno;
|
|
|
|
/* Never send a reset in response to a reset. */
|
|
if (rxdh->dccph_type == DCCP_PKT_RESET)
|
|
return;
|
|
|
|
if (((struct rtable *)rxskb->dst)->rt_type != RTN_LOCAL)
|
|
return;
|
|
|
|
dst = dccp_v4_route_skb(dccp_ctl_socket->sk, rxskb);
|
|
if (dst == NULL)
|
|
return;
|
|
|
|
skb = alloc_skb(MAX_DCCP_HEADER + 15, GFP_ATOMIC);
|
|
if (skb == NULL)
|
|
goto out;
|
|
|
|
/* Reserve space for headers. */
|
|
skb_reserve(skb, MAX_DCCP_HEADER);
|
|
skb->dst = dst_clone(dst);
|
|
|
|
skb->h.raw = skb_push(skb, dccp_hdr_reset_len);
|
|
dh = dccp_hdr(skb);
|
|
memset(dh, 0, dccp_hdr_reset_len);
|
|
|
|
/* Build DCCP header and checksum it. */
|
|
dh->dccph_type = DCCP_PKT_RESET;
|
|
dh->dccph_sport = rxdh->dccph_dport;
|
|
dh->dccph_dport = rxdh->dccph_sport;
|
|
dh->dccph_doff = dccp_hdr_reset_len / 4;
|
|
dh->dccph_x = 1;
|
|
dccp_hdr_reset(skb)->dccph_reset_code =
|
|
DCCP_SKB_CB(rxskb)->dccpd_reset_code;
|
|
|
|
/* See "8.3.1. Abnormal Termination" in draft-ietf-dccp-spec-11 */
|
|
seqno = 0;
|
|
if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
|
|
dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1);
|
|
|
|
dccp_hdr_set_seq(dh, seqno);
|
|
dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
|
|
DCCP_SKB_CB(rxskb)->dccpd_seq);
|
|
|
|
dh->dccph_checksum = dccp_v4_checksum(skb, rxskb->nh.iph->saddr,
|
|
rxskb->nh.iph->daddr);
|
|
|
|
bh_lock_sock(dccp_ctl_socket->sk);
|
|
err = ip_build_and_send_pkt(skb, dccp_ctl_socket->sk,
|
|
rxskb->nh.iph->daddr,
|
|
rxskb->nh.iph->saddr, NULL);
|
|
bh_unlock_sock(dccp_ctl_socket->sk);
|
|
|
|
if (err == NET_XMIT_CN || err == 0) {
|
|
DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
|
|
DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
|
|
}
|
|
out:
|
|
dst_release(dst);
|
|
}
|
|
|
|
int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct dccp_hdr *dh = dccp_hdr(skb);
|
|
|
|
if (sk->sk_state == DCCP_OPEN) { /* Fast path */
|
|
if (dccp_rcv_established(sk, skb, dh, skb->len))
|
|
goto reset;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Step 3: Process LISTEN state
|
|
* If S.state == LISTEN,
|
|
* If P.type == Request or P contains a valid Init Cookie
|
|
* option,
|
|
* * Must scan the packet's options to check for an Init
|
|
* Cookie. Only the Init Cookie is processed here,
|
|
* however; other options are processed in Step 8. This
|
|
* scan need only be performed if the endpoint uses Init
|
|
* Cookies *
|
|
* * Generate a new socket and switch to that socket *
|
|
* Set S := new socket for this port pair
|
|
* S.state = RESPOND
|
|
* Choose S.ISS (initial seqno) or set from Init Cookie
|
|
* Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
|
|
* Continue with S.state == RESPOND
|
|
* * A Response packet will be generated in Step 11 *
|
|
* Otherwise,
|
|
* Generate Reset(No Connection) unless P.type == Reset
|
|
* Drop packet and return
|
|
*
|
|
* NOTE: the check for the packet types is done in
|
|
* dccp_rcv_state_process
|
|
*/
|
|
if (sk->sk_state == DCCP_LISTEN) {
|
|
struct sock *nsk = dccp_v4_hnd_req(sk, skb);
|
|
|
|
if (nsk == NULL)
|
|
goto discard;
|
|
|
|
if (nsk != sk) {
|
|
if (dccp_child_process(sk, nsk, skb))
|
|
goto reset;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
if (dccp_rcv_state_process(sk, skb, dh, skb->len))
|
|
goto reset;
|
|
return 0;
|
|
|
|
reset:
|
|
dccp_v4_ctl_send_reset(skb);
|
|
discard:
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
static inline int dccp_invalid_packet(struct sk_buff *skb)
|
|
{
|
|
const struct dccp_hdr *dh;
|
|
|
|
if (skb->pkt_type != PACKET_HOST)
|
|
return 1;
|
|
|
|
if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) {
|
|
LIMIT_NETDEBUG(KERN_WARNING "DCCP: pskb_may_pull failed\n");
|
|
return 1;
|
|
}
|
|
|
|
dh = dccp_hdr(skb);
|
|
|
|
/* If the packet type is not understood, drop packet and return */
|
|
if (dh->dccph_type >= DCCP_PKT_INVALID) {
|
|
LIMIT_NETDEBUG(KERN_WARNING "DCCP: invalid packet type\n");
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* If P.Data Offset is too small for packet type, or too large for
|
|
* packet, drop packet and return
|
|
*/
|
|
if (dh->dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) {
|
|
LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) "
|
|
"too small 1\n",
|
|
dh->dccph_doff);
|
|
return 1;
|
|
}
|
|
|
|
if (!pskb_may_pull(skb, dh->dccph_doff * sizeof(u32))) {
|
|
LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) "
|
|
"too small 2\n",
|
|
dh->dccph_doff);
|
|
return 1;
|
|
}
|
|
|
|
dh = dccp_hdr(skb);
|
|
|
|
/*
|
|
* If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet
|
|
* has short sequence numbers), drop packet and return
|
|
*/
|
|
if (dh->dccph_x == 0 &&
|
|
dh->dccph_type != DCCP_PKT_DATA &&
|
|
dh->dccph_type != DCCP_PKT_ACK &&
|
|
dh->dccph_type != DCCP_PKT_DATAACK) {
|
|
LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.type (%s) not Data, Ack "
|
|
"nor DataAck and P.X == 0\n",
|
|
dccp_packet_name(dh->dccph_type));
|
|
return 1;
|
|
}
|
|
|
|
/* If the header checksum is incorrect, drop packet and return */
|
|
if (dccp_v4_verify_checksum(skb, skb->nh.iph->saddr,
|
|
skb->nh.iph->daddr) < 0) {
|
|
LIMIT_NETDEBUG(KERN_WARNING "DCCP: header checksum is "
|
|
"incorrect\n");
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* this is called when real data arrives */
|
|
int dccp_v4_rcv(struct sk_buff *skb)
|
|
{
|
|
const struct dccp_hdr *dh;
|
|
struct sock *sk;
|
|
int rc;
|
|
|
|
/* Step 1: Check header basics: */
|
|
|
|
if (dccp_invalid_packet(skb))
|
|
goto discard_it;
|
|
|
|
dh = dccp_hdr(skb);
|
|
#if 0
|
|
/*
|
|
* Use something like this to simulate some DATA/DATAACK loss to test
|
|
* dccp_ackpkts_add, you'll get something like this on a session that
|
|
* sends 10 DATA/DATAACK packets:
|
|
*
|
|
* ackpkts_print: 281473596467422 |0,0|3,0|0,0|3,0|0,0|3,0|0,0|3,0|0,1|
|
|
*
|
|
* 0, 0 means: DCCP_ACKPKTS_STATE_RECEIVED, RLE == just this packet
|
|
* 0, 1 means: DCCP_ACKPKTS_STATE_RECEIVED, RLE == two adjacent packets
|
|
* with the same state
|
|
* 3, 0 means: DCCP_ACKPKTS_STATE_NOT_RECEIVED, RLE == just this packet
|
|
*
|
|
* So...
|
|
*
|
|
* 281473596467422 was received
|
|
* 281473596467421 was not received
|
|
* 281473596467420 was received
|
|
* 281473596467419 was not received
|
|
* 281473596467418 was received
|
|
* 281473596467417 was not received
|
|
* 281473596467416 was received
|
|
* 281473596467415 was not received
|
|
* 281473596467414 was received
|
|
* 281473596467413 was received (this one was the 3way handshake
|
|
* RESPONSE)
|
|
*
|
|
*/
|
|
if (dh->dccph_type == DCCP_PKT_DATA ||
|
|
dh->dccph_type == DCCP_PKT_DATAACK) {
|
|
static int discard = 0;
|
|
|
|
if (discard) {
|
|
discard = 0;
|
|
goto discard_it;
|
|
}
|
|
discard = 1;
|
|
}
|
|
#endif
|
|
DCCP_SKB_CB(skb)->dccpd_seq = dccp_hdr_seq(skb);
|
|
DCCP_SKB_CB(skb)->dccpd_type = dh->dccph_type;
|
|
|
|
dccp_pr_debug("%8.8s "
|
|
"src=%u.%u.%u.%u@%-5d "
|
|
"dst=%u.%u.%u.%u@%-5d seq=%llu",
|
|
dccp_packet_name(dh->dccph_type),
|
|
NIPQUAD(skb->nh.iph->saddr), ntohs(dh->dccph_sport),
|
|
NIPQUAD(skb->nh.iph->daddr), ntohs(dh->dccph_dport),
|
|
(unsigned long long) DCCP_SKB_CB(skb)->dccpd_seq);
|
|
|
|
if (dccp_packet_without_ack(skb)) {
|
|
DCCP_SKB_CB(skb)->dccpd_ack_seq = DCCP_PKT_WITHOUT_ACK_SEQ;
|
|
dccp_pr_debug_cat("\n");
|
|
} else {
|
|
DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
|
|
dccp_pr_debug_cat(", ack=%llu\n",
|
|
(unsigned long long)
|
|
DCCP_SKB_CB(skb)->dccpd_ack_seq);
|
|
}
|
|
|
|
/* Step 2:
|
|
* Look up flow ID in table and get corresponding socket */
|
|
sk = __inet_lookup(&dccp_hashinfo,
|
|
skb->nh.iph->saddr, dh->dccph_sport,
|
|
skb->nh.iph->daddr, ntohs(dh->dccph_dport),
|
|
inet_iif(skb));
|
|
|
|
/*
|
|
* Step 2:
|
|
* If no socket ...
|
|
* Generate Reset(No Connection) unless P.type == Reset
|
|
* Drop packet and return
|
|
*/
|
|
if (sk == NULL) {
|
|
dccp_pr_debug("failed to look up flow ID in table and "
|
|
"get corresponding socket\n");
|
|
goto no_dccp_socket;
|
|
}
|
|
|
|
/*
|
|
* Step 2:
|
|
* ... or S.state == TIMEWAIT,
|
|
* Generate Reset(No Connection) unless P.type == Reset
|
|
* Drop packet and return
|
|
*/
|
|
|
|
if (sk->sk_state == DCCP_TIME_WAIT) {
|
|
dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: "
|
|
"do_time_wait\n");
|
|
goto do_time_wait;
|
|
}
|
|
|
|
if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) {
|
|
dccp_pr_debug("xfrm4_policy_check failed\n");
|
|
goto discard_and_relse;
|
|
}
|
|
|
|
if (sk_filter(sk, skb, 0)) {
|
|
dccp_pr_debug("sk_filter failed\n");
|
|
goto discard_and_relse;
|
|
}
|
|
|
|
skb->dev = NULL;
|
|
|
|
bh_lock_sock(sk);
|
|
rc = 0;
|
|
if (!sock_owned_by_user(sk))
|
|
rc = dccp_v4_do_rcv(sk, skb);
|
|
else
|
|
sk_add_backlog(sk, skb);
|
|
bh_unlock_sock(sk);
|
|
|
|
sock_put(sk);
|
|
return rc;
|
|
|
|
no_dccp_socket:
|
|
if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
|
|
goto discard_it;
|
|
/*
|
|
* Step 2:
|
|
* Generate Reset(No Connection) unless P.type == Reset
|
|
* Drop packet and return
|
|
*/
|
|
if (dh->dccph_type != DCCP_PKT_RESET) {
|
|
DCCP_SKB_CB(skb)->dccpd_reset_code =
|
|
DCCP_RESET_CODE_NO_CONNECTION;
|
|
dccp_v4_ctl_send_reset(skb);
|
|
}
|
|
|
|
discard_it:
|
|
/* Discard frame. */
|
|
kfree_skb(skb);
|
|
return 0;
|
|
|
|
discard_and_relse:
|
|
sock_put(sk);
|
|
goto discard_it;
|
|
|
|
do_time_wait:
|
|
inet_twsk_put((struct inet_timewait_sock *)sk);
|
|
goto no_dccp_socket;
|
|
}
|
|
|
|
static int dccp_v4_init_sock(struct sock *sk)
|
|
{
|
|
struct dccp_sock *dp = dccp_sk(sk);
|
|
static int dccp_ctl_socket_init = 1;
|
|
|
|
dccp_options_init(&dp->dccps_options);
|
|
do_gettimeofday(&dp->dccps_epoch);
|
|
|
|
if (dp->dccps_options.dccpo_send_ack_vector) {
|
|
dp->dccps_hc_rx_ackpkts =
|
|
dccp_ackpkts_alloc(DCCP_MAX_ACK_VECTOR_LEN,
|
|
GFP_KERNEL);
|
|
|
|
if (dp->dccps_hc_rx_ackpkts == NULL)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/*
|
|
* FIXME: We're hardcoding the CCID, and doing this at this point makes
|
|
* the listening (master) sock get CCID control blocks, which is not
|
|
* necessary, but for now, to not mess with the test userspace apps,
|
|
* lets leave it here, later the real solution is to do this in a
|
|
* setsockopt(CCIDs-I-want/accept). -acme
|
|
*/
|
|
if (likely(!dccp_ctl_socket_init)) {
|
|
dp->dccps_hc_rx_ccid = ccid_init(dp->dccps_options.dccpo_ccid,
|
|
sk);
|
|
dp->dccps_hc_tx_ccid = ccid_init(dp->dccps_options.dccpo_ccid,
|
|
sk);
|
|
if (dp->dccps_hc_rx_ccid == NULL ||
|
|
dp->dccps_hc_tx_ccid == NULL) {
|
|
ccid_exit(dp->dccps_hc_rx_ccid, sk);
|
|
ccid_exit(dp->dccps_hc_tx_ccid, sk);
|
|
dccp_ackpkts_free(dp->dccps_hc_rx_ackpkts);
|
|
dp->dccps_hc_rx_ackpkts = NULL;
|
|
dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
|
|
return -ENOMEM;
|
|
}
|
|
} else
|
|
dccp_ctl_socket_init = 0;
|
|
|
|
dccp_init_xmit_timers(sk);
|
|
inet_csk(sk)->icsk_rto = DCCP_TIMEOUT_INIT;
|
|
sk->sk_state = DCCP_CLOSED;
|
|
sk->sk_write_space = dccp_write_space;
|
|
dp->dccps_mss_cache = 536;
|
|
dp->dccps_role = DCCP_ROLE_UNDEFINED;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dccp_v4_destroy_sock(struct sock *sk)
|
|
{
|
|
struct dccp_sock *dp = dccp_sk(sk);
|
|
|
|
/*
|
|
* DCCP doesn't use sk_qrite_queue, just sk_send_head
|
|
* for retransmissions
|
|
*/
|
|
if (sk->sk_send_head != NULL) {
|
|
kfree_skb(sk->sk_send_head);
|
|
sk->sk_send_head = NULL;
|
|
}
|
|
|
|
/* Clean up a referenced DCCP bind bucket. */
|
|
if (inet_csk(sk)->icsk_bind_hash != NULL)
|
|
inet_put_port(&dccp_hashinfo, sk);
|
|
|
|
ccid_hc_rx_exit(dp->dccps_hc_rx_ccid, sk);
|
|
ccid_hc_tx_exit(dp->dccps_hc_tx_ccid, sk);
|
|
dccp_ackpkts_free(dp->dccps_hc_rx_ackpkts);
|
|
dp->dccps_hc_rx_ackpkts = NULL;
|
|
ccid_exit(dp->dccps_hc_rx_ccid, sk);
|
|
ccid_exit(dp->dccps_hc_tx_ccid, sk);
|
|
dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void dccp_v4_reqsk_destructor(struct request_sock *req)
|
|
{
|
|
kfree(inet_rsk(req)->opt);
|
|
}
|
|
|
|
static struct request_sock_ops dccp_request_sock_ops = {
|
|
.family = PF_INET,
|
|
.obj_size = sizeof(struct dccp_request_sock),
|
|
.rtx_syn_ack = dccp_v4_send_response,
|
|
.send_ack = dccp_v4_reqsk_send_ack,
|
|
.destructor = dccp_v4_reqsk_destructor,
|
|
.send_reset = dccp_v4_ctl_send_reset,
|
|
};
|
|
|
|
struct proto dccp_v4_prot = {
|
|
.name = "DCCP",
|
|
.owner = THIS_MODULE,
|
|
.close = dccp_close,
|
|
.connect = dccp_v4_connect,
|
|
.disconnect = dccp_disconnect,
|
|
.ioctl = dccp_ioctl,
|
|
.init = dccp_v4_init_sock,
|
|
.setsockopt = dccp_setsockopt,
|
|
.getsockopt = dccp_getsockopt,
|
|
.sendmsg = dccp_sendmsg,
|
|
.recvmsg = dccp_recvmsg,
|
|
.backlog_rcv = dccp_v4_do_rcv,
|
|
.hash = dccp_v4_hash,
|
|
.unhash = dccp_v4_unhash,
|
|
.accept = inet_csk_accept,
|
|
.get_port = dccp_v4_get_port,
|
|
.shutdown = dccp_shutdown,
|
|
.destroy = dccp_v4_destroy_sock,
|
|
.orphan_count = &dccp_orphan_count,
|
|
.max_header = MAX_DCCP_HEADER,
|
|
.obj_size = sizeof(struct dccp_sock),
|
|
.rsk_prot = &dccp_request_sock_ops,
|
|
.twsk_obj_size = sizeof(struct inet_timewait_sock),
|
|
};
|