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