git.oblomov.eu Git - linux-2.6/blob - net/ipv6/inet6_connection_sock.c

   1 /*
   2  * INET        An implementation of the TCP/IP protocol suite for the LINUX
   3  *             operating system.  INET is implemented using the  BSD Socket
   4  *             interface as the means of communication with the user level.
   5  *
   6  *             Support for INET6 connection oriented protocols.
   7  *
   8  * Authors:    See the TCPv6 sources
   9  *
  10  *             This program is free software; you can redistribute it and/or
  11  *             modify it under the terms of the GNU General Public License
  12  *             as published by the Free Software Foundation; either version
  13  *             2 of the License, or(at your option) any later version.
  14  */
  15
  16 #include <linux/config.h>
  17 #include <linux/module.h>
  18 #include <linux/in6.h>
  19 #include <linux/ipv6.h>
  20 #include <linux/jhash.h>
  21
  22 #include <net/addrconf.h>
  23 #include <net/inet_connection_sock.h>
  24 #include <net/sock.h>
  25
  26 /*
  27  * request_sock (formerly open request) hash tables.
  28  */
  29 static u32 inet6_synq_hash(const struct in6_addr *raddr, const u16 rport,
  30                            const u32 rnd, const u16 synq_hsize)
  31 {
  32         u32 a = raddr->s6_addr32[0];
  33         u32 b = raddr->s6_addr32[1];
  34         u32 c = raddr->s6_addr32[2];
  35
  36         a += JHASH_GOLDEN_RATIO;
  37         b += JHASH_GOLDEN_RATIO;
  38         c += rnd;
  39         __jhash_mix(a, b, c);
  40
  41         a += raddr->s6_addr32[3];
  42         b += (u32)rport;
  43         __jhash_mix(a, b, c);
  44
  45         return c & (synq_hsize - 1);
  46 }
  47
  48 struct request_sock *inet6_csk_search_req(const struct sock *sk,
  49                                           struct request_sock ***prevp,
  50                                           const __u16 rport,
  51                                           const struct in6_addr *raddr,
  52                                           const struct in6_addr *laddr,
  53                                           const int iif)
  54 {
  55         const struct inet_connection_sock *icsk = inet_csk(sk);
  56         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
  57         struct request_sock *req, **prev;
  58
  59         for (prev = &lopt->syn_table[inet6_synq_hash(raddr, rport,
  60                                                      lopt->hash_rnd,
  61                                                      lopt->nr_table_entries)];
  62              (req = *prev) != NULL;
  63              prev = &req->dl_next) {
  64                 const struct tcp6_request_sock *treq = tcp6_rsk(req);
  65
  66                 if (inet_rsk(req)->rmt_port == rport &&
  67                     req->rsk_ops->family == AF_INET6 &&
  68                     ipv6_addr_equal(&treq->rmt_addr, raddr) &&
  69                     ipv6_addr_equal(&treq->loc_addr, laddr) &&
  70                     (!treq->iif || treq->iif == iif)) {
  71                         BUG_TRAP(req->sk == NULL);
  72                         *prevp = prev;
  73                         return req;
  74                 }
  75         }
  76
  77         return NULL;
  78 }
  79
  80 EXPORT_SYMBOL_GPL(inet6_csk_search_req);
  81
  82 void inet6_csk_reqsk_queue_hash_add(struct sock *sk,
  83                                     struct request_sock *req,
  84                                     const unsigned long timeout)
  85 {
  86         struct inet_connection_sock *icsk = inet_csk(sk);
  87         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
  88         const u32 h = inet6_synq_hash(&tcp6_rsk(req)->rmt_addr,
  89                                       inet_rsk(req)->rmt_port,
  90                                       lopt->hash_rnd, lopt->nr_table_entries);
  91
  92         reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
  93         inet_csk_reqsk_queue_added(sk, timeout);
  94 }
  95
  96 EXPORT_SYMBOL_GPL(inet6_csk_reqsk_queue_hash_add);