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 static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
  61                                  int *addr_len)
  62 {
  63         return -EAFNOSUPPORT;
  64 }
  65 static int dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
  66                                        struct sk_buff *skb)
  67 {
  68         return -EAFNOSUPPORT;
  69 }
  70 static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
  71 {
  72         return -EAFNOSUPPORT;
  73 }
  74 static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
  75                                   __be16 port, u32 info, u8 *payload) {}
  76 static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
  77                                const struct net_device *dev, int strict)
  78 {
  79         return 0;
  80 }
  81
  82 int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
  83                     size_t len)
  84 {
  85         struct inet_sock *inet = inet_sk(sk);
  86         struct ipv6_pinfo *np = inet6_sk(sk);
  87         struct icmp6hdr user_icmph;
  88         int addr_type;
  89         struct in6_addr *daddr;
  90         int iif = 0;
  91         struct flowi6 fl6;
  92         int err;
  93         int hlimit;
  94         struct dst_entry *dst;
  95         struct rt6_info *rt;
  96         struct pingfakehdr pfh;
  97
  98         pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
  99
 100         err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
 101                                   sizeof(user_icmph));
 102         if (err)
 103                 return err;
 104
 105         if (msg->msg_name) {
 106                 struct sockaddr_in6 *u = (struct sockaddr_in6 *) msg->msg_name;
 107                 if (msg->msg_namelen < sizeof(struct sockaddr_in6) ||
 108                     u->sin6_family != AF_INET6) {
 109                         return -EINVAL;
 110                 }
 111                 if (sk->sk_bound_dev_if &&
 112                     sk->sk_bound_dev_if != u->sin6_scope_id) {
 113                         return -EINVAL;
 114                 }
 115                 daddr = &(u->sin6_addr);
 116                 iif = u->sin6_scope_id;
 117         } else {
 118                 if (sk->sk_state != TCP_ESTABLISHED)
 119                         return -EDESTADDRREQ;
 120                 daddr = &sk->sk_v6_daddr;
 121         }
 122
 123         if (!iif)
 124                 iif = sk->sk_bound_dev_if;
 125
 126         addr_type = ipv6_addr_type(daddr);
 127         if (__ipv6_addr_needs_scope_id(addr_type) && !iif)
 128                 return -EINVAL;
 129         if (addr_type & IPV6_ADDR_MAPPED)
 130                 return -EINVAL;
 131
 132         /* TODO: use ip6_datagram_send_ctl to get options from cmsg */
 133
 134         memset(&fl6, 0, sizeof(fl6));
 135
 136         fl6.flowi6_proto = IPPROTO_ICMPV6;
 137         fl6.saddr = np->saddr;
 138         fl6.daddr = *daddr;
 139         fl6.fl6_icmp_type = user_icmph.icmp6_type;
 140         fl6.fl6_icmp_code = user_icmph.icmp6_code;
 141         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 142
 143         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 144                 fl6.flowi6_oif = np->mcast_oif;
 145         else if (!fl6.flowi6_oif)
 146                 fl6.flowi6_oif = np->ucast_oif;
 147
 148         dst = ip6_sk_dst_lookup_flow(sk, &fl6,  daddr, 1);
 149         if (IS_ERR(dst))
 150                 return PTR_ERR(dst);
 151         rt = (struct rt6_info *) dst;
 152
 153         np = inet6_sk(sk);
 154         if (!np)
 155                 return -EBADF;
 156
 157         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 158                 fl6.flowi6_oif = np->mcast_oif;
 159         else if (!fl6.flowi6_oif)
 160                 fl6.flowi6_oif = np->ucast_oif;
 161
 162         pfh.icmph.type = user_icmph.icmp6_type;
 163         pfh.icmph.code = user_icmph.icmp6_code;
 164         pfh.icmph.checksum = 0;
 165         pfh.icmph.un.echo.id = inet->inet_sport;
 166         pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
 167         pfh.iov = msg->msg_iov;
 168         pfh.wcheck = 0;
 169         pfh.family = AF_INET6;
 170
 171         if (ipv6_addr_is_multicast(&fl6.daddr))
 172                 hlimit = np->mcast_hops;
 173         else
 174                 hlimit = np->hop_limit;
 175         if (hlimit < 0)
 176                 hlimit = ip6_dst_hoplimit(dst);
 177
 178         lock_sock(sk);
 179         err = ip6_append_data(sk, ping_getfrag, &pfh, len,
 180                               0, hlimit,
 181                               np->tclass, NULL, &fl6, rt,
 182                               MSG_DONTWAIT, np->dontfrag);
 183
 184         if (err) {
 185                 ICMP6_INC_STATS_BH(sock_net(sk), rt->rt6i_idev,
 186                                    ICMP6_MIB_OUTERRORS);
 187                 ip6_flush_pending_frames(sk);
 188         } else {
 189                 err = icmpv6_push_pending_frames(sk, &fl6,
 190                                                  (struct icmp6hdr *) &pfh.icmph,
 191                                                  len);
 192         }
 193         release_sock(sk);
 194
 195         if (err)
 196                 return err;
 197
 198         return len;
 199 }
 200
 201 #ifdef CONFIG_PROC_FS
 202 static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
 203 {
 204         return ping_seq_start(seq, pos, AF_INET6);
 205 }
 206
 207 static int ping_v6_seq_show(struct seq_file *seq, void *v)
 208 {
 209         if (v == SEQ_START_TOKEN) {
 210                 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
 211         } else {
 212                 int bucket = ((struct ping_iter_state *) seq->private)->bucket;
 213                 struct inet_sock *inet = inet_sk(v);
 214                 __u16 srcp = ntohs(inet->inet_sport);
 215                 __u16 destp = ntohs(inet->inet_dport);
 216                 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
 217         }
 218         return 0;
 219 }
 220
 221 static struct ping_seq_afinfo ping_v6_seq_afinfo = {
 222         .name           = "icmp6",
 223         .family         = AF_INET6,
 224         .seq_fops       = &ping_seq_fops,
 225         .seq_ops        = {
 226                 .start          = ping_v6_seq_start,
 227                 .show           = ping_v6_seq_show,
 228                 .next           = ping_seq_next,
 229                 .stop           = ping_seq_stop,
 230         },
 231 };
 232
 233 static int __net_init ping_v6_proc_init_net(struct net *net)
 234 {
 235         return ping_proc_register(net, &ping_v6_seq_afinfo);
 236 }
 237
 238 static void __net_init ping_v6_proc_exit_net(struct net *net)
 239 {
 240         return ping_proc_unregister(net, &ping_v6_seq_afinfo);
 241 }
 242
 243 static struct pernet_operations ping_v6_net_ops = {
 244         .init = ping_v6_proc_init_net,
 245         .exit = ping_v6_proc_exit_net,
 246 };
 247 #endif
 248
 249 int __init pingv6_init(void)
 250 {
 251 #ifdef CONFIG_PROC_FS
 252         int ret = register_pernet_subsys(&ping_v6_net_ops);
 253         if (ret)
 254                 return ret;
 255 #endif
 256         pingv6_ops.ipv6_recv_error = ipv6_recv_error;
 257         pingv6_ops.ip6_datagram_recv_ctl = ip6_datagram_recv_ctl;
 258         pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
 259         pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
 260         pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
 261         return inet6_register_protosw(&pingv6_protosw);
 262 }
 263
 264 /* This never gets called because it's not possible to unload the ipv6 module,
 265  * but just in case.
 266  */
 267 void pingv6_exit(void)
 268 {
 269         pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
 270         pingv6_ops.ip6_datagram_recv_ctl = dummy_ip6_datagram_recv_ctl;
 271         pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
 272         pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
 273         pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
 274 #ifdef CONFIG_PROC_FS
 275         unregister_pernet_subsys(&ping_v6_net_ops);
 276 #endif
 277         inet6_unregister_protosw(&pingv6_protosw);
 278 }