net/ipv6/ping.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  *              "Ping" sockets
   7  *
   8  *              This program is free software; you can redistribute it and/or
   9  *              modify it under the terms of the GNU General Public License
  10  *              as published by the Free Software Foundation; either version
  11  *              2 of the License, or (at your option) any later version.
  12  *
  13  * Based on ipv4/ping.c code.
  14  *
  15  * Authors:     Lorenzo Colitti (IPv6 support)
  16  *              Vasiliy Kulikov / Openwall (IPv4 implementation, for Linux 2.6),
  17  *              Pavel Kankovsky (IPv4 implementation, for Linux 2.4.32)
  18  *
  19  */
  20
  21 #include <net/addrconf.h>
  22 #include <net/ipv6.h>
  23 #include <net/ip6_route.h>
  24 #include <net/protocol.h>
  25 #include <net/udp.h>
  26 #include <net/transp_v6.h>
  27 #include <net/ping.h>
  28
  29 struct proto pingv6_prot = {
  30         .name =         "PINGv6",
  31         .owner =        THIS_MODULE,
  32         .init =         ping_init_sock,
  33         .close =        ping_close,
  34         .connect =      ip6_datagram_connect,
  35         .disconnect =   udp_disconnect,
  36         .setsockopt =   ipv6_setsockopt,
  37         .getsockopt =   ipv6_getsockopt,
  38         .sendmsg =      ping_v6_sendmsg,
  39         .recvmsg =      ping_recvmsg,
  40         .bind =         ping_bind,
  41         .backlog_rcv =  ping_queue_rcv_skb,
  42         .hash =         ping_hash,
  43         .unhash =       ping_unhash,
  44         .get_port =     ping_get_port,
  45         .obj_size =     sizeof(struct raw6_sock),
  46 };
  47 EXPORT_SYMBOL_GPL(pingv6_prot);
  48
  49 static struct inet_protosw pingv6_protosw = {
  50         .type =      SOCK_DGRAM,
  51         .protocol =  IPPROTO_ICMPV6,
  52         .prot =      &pingv6_prot,
  53         .ops =       &inet6_dgram_ops,
  54         .no_check =  UDP_CSUM_DEFAULT,
  55         .flags =     INET_PROTOSW_REUSE,
  56 };
  57
  58
  59 /* Compatibility glue so we can support IPv6 when it's compiled as a module */
  60 int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
  61 {
  62         return -EAFNOSUPPORT;
  63 }
  64 int dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
  65                                  struct sk_buff *skb)
  66 {
  67         return -EAFNOSUPPORT;
  68 }
  69 int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
  70 {
  71         return -EAFNOSUPPORT;
  72 }
  73 void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
  74                             __be16 port, u32 info, u8 *payload) {}
  75 int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
  76                         const struct net_device *dev, int strict)
  77 {
  78         return 0;
  79 }
  80
  81 int __init pingv6_init(void)
  82 {
  83         pingv6_ops.ipv6_recv_error = ipv6_recv_error;
  84         pingv6_ops.ip6_datagram_recv_ctl = ip6_datagram_recv_ctl;
  85         pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
  86         pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
  87         pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
  88         return inet6_register_protosw(&pingv6_protosw);
  89 }
  90
  91 /* This never gets called because it's not possible to unload the ipv6 module,
  92  * but just in case.
  93  */
  94 void pingv6_exit(void)
  95 {
  96         pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
  97         pingv6_ops.ip6_datagram_recv_ctl = dummy_ip6_datagram_recv_ctl;
  98         pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
  99         pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
 100         pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
 101         inet6_unregister_protosw(&pingv6_protosw);
 102 }
 103
 104 int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 105                     size_t len)
 106 {
 107         struct inet_sock *inet = inet_sk(sk);
 108         struct ipv6_pinfo *np = inet6_sk(sk);
 109         struct icmp6hdr user_icmph;
 110         int addr_type;
 111         struct in6_addr *daddr;
 112         int iif = 0;
 113         struct flowi6 fl6;
 114         int err;
 115         int hlimit;
 116         struct dst_entry *dst;
 117         struct rt6_info *rt;
 118         struct pingfakehdr pfh;
 119
 120         pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
 121
 122         err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
 123                                   sizeof(user_icmph));
 124         if (err)
 125                 return err;
 126
 127         if (msg->msg_name) {
 128                 struct sockaddr_in6 *u = (struct sockaddr_in6 *) msg->msg_name;
 129                 if (msg->msg_namelen < sizeof(*u))
 130                         return -EINVAL;
 131                 if (u->sin6_family != AF_INET6) {
 132                         return -EAFNOSUPPORT;
 133                 }
 134                 if (sk->sk_bound_dev_if &&
 135                     sk->sk_bound_dev_if != u->sin6_scope_id) {
 136                         return -EINVAL;
 137                 }
 138                 daddr = &(u->sin6_addr);
 139                 iif = u->sin6_scope_id;
 140         } else {
 141                 if (sk->sk_state != TCP_ESTABLISHED)
 142                         return -EDESTADDRREQ;
 143                 daddr = &np->daddr;
 144         }
 145
 146         if (!iif)
 147                 iif = sk->sk_bound_dev_if;
 148
 149         addr_type = ipv6_addr_type(daddr);
 150         if (__ipv6_addr_needs_scope_id(addr_type) && !iif)
 151                 return -EINVAL;
 152         if (addr_type & IPV6_ADDR_MAPPED)
 153                 return -EINVAL;
 154
 155         /* TODO: use ip6_datagram_send_ctl to get options from cmsg */
 156
 157         memset(&fl6, 0, sizeof(fl6));
 158
 159         fl6.flowi6_proto = IPPROTO_ICMPV6;
 160         fl6.saddr = np->saddr;
 161         fl6.daddr = *daddr;
 162         fl6.flowi6_mark = sk->sk_mark;
 163         fl6.flowi6_uid = sock_i_uid(sk);
 164         fl6.fl6_icmp_type = user_icmph.icmp6_type;
 165         fl6.fl6_icmp_code = user_icmph.icmp6_code;
 166         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 167
 168         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 169                 fl6.flowi6_oif = np->mcast_oif;
 170         else if (!fl6.flowi6_oif)
 171                 fl6.flowi6_oif = np->ucast_oif;
 172
 173         dst = ip6_sk_dst_lookup_flow(sk, &fl6,  daddr, 1);
 174         if (IS_ERR(dst))
 175                 return PTR_ERR(dst);
 176         rt = (struct rt6_info *) dst;
 177
 178         np = inet6_sk(sk);
 179         if (!np)
 180                 return -EBADF;
 181
 182         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 183                 fl6.flowi6_oif = np->mcast_oif;
 184         else if (!fl6.flowi6_oif)
 185                 fl6.flowi6_oif = np->ucast_oif;
 186
 187         pfh.icmph.type = user_icmph.icmp6_type;
 188         pfh.icmph.code = user_icmph.icmp6_code;
 189         pfh.icmph.checksum = 0;
 190         pfh.icmph.un.echo.id = inet->inet_sport;
 191         pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
 192         pfh.iov = msg->msg_iov;
 193         pfh.wcheck = 0;
 194         pfh.family = AF_INET6;
 195
 196         if (ipv6_addr_is_multicast(&fl6.daddr))
 197                 hlimit = np->mcast_hops;
 198         else
 199                 hlimit = np->hop_limit;
 200         if (hlimit < 0)
 201                 hlimit = ip6_dst_hoplimit(dst);
 202
 203         lock_sock(sk);
 204         err = ip6_append_data(sk, ping_getfrag, &pfh, len,
 205                               0, hlimit,
 206                               np->tclass, NULL, &fl6, rt,
 207                               MSG_DONTWAIT, np->dontfrag);
 208
 209         if (err) {
 210                 ICMP6_INC_STATS_BH(sock_net(sk), rt->rt6i_idev,
 211                                    ICMP6_MIB_OUTERRORS);
 212                 ip6_flush_pending_frames(sk);
 213         } else {
 214                 err = icmpv6_push_pending_frames(sk, &fl6,
 215                                                  (struct icmp6hdr *) &pfh.icmph,
 216                                                  len);
 217         }
 218         release_sock(sk);
 219
 220         if (err)
 221                 return err;
 222
 223         return len;
 224 }