net/rxrpc/utils.c

   1 /* Utility routines
   2  *
   3  * Copyright (C) 2015 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public Licence
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the Licence, or (at your option) any later version.
  10  */
  11
  12 #include <linux/ip.h>
  13 #include <linux/ipv6.h>
  14 #include <linux/udp.h>
  15 #include "ar-internal.h"
  16
  17 /*
  18  * Fill out a peer address from a socket buffer containing a packet.
  19  */
  20 int rxrpc_extract_addr_from_skb(struct rxrpc_local *local,
  21                                 struct sockaddr_rxrpc *srx,
  22                                 struct sk_buff *skb)
  23 {
  24         memset(srx, 0, sizeof(*srx));
  25
  26         switch (ntohs(skb->protocol)) {
  27         case ETH_P_IP:
  28                 if (local->srx.transport.family == AF_INET6) {
  29                         srx->transport_type = SOCK_DGRAM;
  30                         srx->transport_len = sizeof(srx->transport.sin6);
  31                         srx->transport.sin6.sin6_family = AF_INET6;
  32                         srx->transport.sin6.sin6_port = udp_hdr(skb)->source;
  33                         srx->transport.sin6.sin6_addr.s6_addr32[2] = htonl(0xffff);
  34                         srx->transport.sin6.sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr;
  35                 } else {
  36                         srx->transport_type = SOCK_DGRAM;
  37                         srx->transport_len = sizeof(srx->transport.sin);
  38                         srx->transport.sin.sin_family = AF_INET;
  39                         srx->transport.sin.sin_port = udp_hdr(skb)->source;
  40                         srx->transport.sin.sin_addr.s_addr = ip_hdr(skb)->saddr;
  41                 }
  42                 return 0;
  43
  44 #ifdef CONFIG_AF_RXRPC_IPV6
  45         case ETH_P_IPV6:
  46                 srx->transport_type = SOCK_DGRAM;
  47                 srx->transport_len = sizeof(srx->transport.sin6);
  48                 srx->transport.sin6.sin6_family = AF_INET6;
  49                 srx->transport.sin6.sin6_port = udp_hdr(skb)->source;
  50                 srx->transport.sin6.sin6_addr = ipv6_hdr(skb)->saddr;
  51                 return 0;
  52 #endif
  53
  54         default:
  55                 pr_warn_ratelimited("AF_RXRPC: Unknown eth protocol %u\n",
  56                                     ntohs(skb->protocol));
  57                 return -EAFNOSUPPORT;
  58         }
  59 }