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 /* Compatibility glue so we can support IPv6 when it's compiled as a module */
  30 static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
  31                                  int *addr_len)
  32 {
  33         return -EAFNOSUPPORT;
  34 }
  35 static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
  36                                        struct sk_buff *skb)
  37 {
  38 }
  39 static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
  40 {
  41         return -EAFNOSUPPORT;
  42 }
  43 static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
  44                                   __be16 port, u32 info, u8 *payload) {}
  45 static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
  46                                const struct net_device *dev, int strict)
  47 {
  48         return 0;
  49 }
  50
  51 static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
  52 {
  53         struct inet_sock *inet = inet_sk(sk);
  54         struct ipv6_pinfo *np = inet6_sk(sk);
  55         struct icmp6hdr user_icmph;
  56         int addr_type;
  57         struct in6_addr *daddr;
  58         int iif = 0;
  59         struct flowi6 fl6;
  60         int err;
  61         int hlimit;
  62         struct dst_entry *dst;
  63         struct rt6_info *rt;
  64         struct pingfakehdr pfh;
  65
  66         pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
  67
  68         err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
  69                                   sizeof(user_icmph));
  70         if (err)
  71                 return err;
  72
  73         if (msg->msg_name) {
  74                 DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
  75                 if (msg->msg_namelen < sizeof(*u))
  76                         return -EINVAL;
  77                 if (u->sin6_family != AF_INET6) {
  78                         return -EAFNOSUPPORT;
  79                 }
  80                 if (sk->sk_bound_dev_if &&
  81                     sk->sk_bound_dev_if != u->sin6_scope_id) {
  82                         return -EINVAL;
  83                 }
  84                 daddr = &(u->sin6_addr);
  85                 iif = u->sin6_scope_id;
  86         } else {
  87                 if (sk->sk_state != TCP_ESTABLISHED)
  88                         return -EDESTADDRREQ;
  89                 daddr = &sk->sk_v6_daddr;
  90         }
  91
  92         if (!iif)
  93                 iif = sk->sk_bound_dev_if;
  94
  95         addr_type = ipv6_addr_type(daddr);
  96         if (__ipv6_addr_needs_scope_id(addr_type) && !iif)
  97                 return -EINVAL;
  98         if (addr_type & IPV6_ADDR_MAPPED)
  99                 return -EINVAL;
 100
 101         /* TODO: use ip6_datagram_send_ctl to get options from cmsg */
 102
 103         memset(&fl6, 0, sizeof(fl6));
 104
 105         fl6.flowi6_proto = IPPROTO_ICMPV6;
 106         fl6.saddr = np->saddr;
 107         fl6.daddr = *daddr;
 108         fl6.flowi6_mark = sk->sk_mark;
 109         fl6.fl6_icmp_type = user_icmph.icmp6_type;
 110         fl6.fl6_icmp_code = user_icmph.icmp6_code;
 111         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 112
 113         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 114                 fl6.flowi6_oif = np->mcast_oif;
 115         else if (!fl6.flowi6_oif)
 116                 fl6.flowi6_oif = np->ucast_oif;
 117
 118         dst = ip6_sk_dst_lookup_flow(sk, &fl6,  daddr);
 119         if (IS_ERR(dst))
 120                 return PTR_ERR(dst);
 121         rt = (struct rt6_info *) dst;
 122
 123         np = inet6_sk(sk);
 124         if (!np)
 125                 return -EBADF;
 126
 127         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 128                 fl6.flowi6_oif = np->mcast_oif;
 129         else if (!fl6.flowi6_oif)
 130                 fl6.flowi6_oif = np->ucast_oif;
 131
 132         pfh.icmph.type = user_icmph.icmp6_type;
 133         pfh.icmph.code = user_icmph.icmp6_code;
 134         pfh.icmph.checksum = 0;
 135         pfh.icmph.un.echo.id = inet->inet_sport;
 136         pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
 137         pfh.msg = msg;
 138         pfh.wcheck = 0;
 139         pfh.family = AF_INET6;
 140
 141         hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 142
 143         lock_sock(sk);
 144         err = ip6_append_data(sk, ping_getfrag, &pfh, len,
 145                               0, hlimit,
 146                               np->tclass, NULL, &fl6, rt,
 147                               MSG_DONTWAIT, np->dontfrag);
 148
 149         if (err) {
 150                 ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
 151                                 ICMP6_MIB_OUTERRORS);
 152                 ip6_flush_pending_frames(sk);
 153         } else {
 154                 err = icmpv6_push_pending_frames(sk, &fl6,
 155                                                  (struct icmp6hdr *) &pfh.icmph,
 156                                                  len);
 157         }
 158         release_sock(sk);
 159
 160         if (err)
 161                 return err;
 162
 163         return len;
 164 }
 165
 166 struct proto pingv6_prot = {
 167         .name =         "PINGv6",
 168         .owner =        THIS_MODULE,
 169         .init =         ping_init_sock,
 170         .close =        ping_close,
 171         .connect =      ip6_datagram_connect_v6_only,
 172         .disconnect =   udp_disconnect,
 173         .setsockopt =   ipv6_setsockopt,
 174         .getsockopt =   ipv6_getsockopt,
 175         .sendmsg =      ping_v6_sendmsg,
 176         .recvmsg =      ping_recvmsg,
 177         .bind =         ping_bind,
 178         .backlog_rcv =  ping_queue_rcv_skb,
 179         .hash =         ping_hash,
 180         .unhash =       ping_unhash,
 181         .get_port =     ping_get_port,
 182         .obj_size =     sizeof(struct raw6_sock),
 183 };
 184 EXPORT_SYMBOL_GPL(pingv6_prot);
 185
 186 static struct inet_protosw pingv6_protosw = {
 187         .type =      SOCK_DGRAM,
 188         .protocol =  IPPROTO_ICMPV6,
 189         .prot =      &pingv6_prot,
 190         .ops =       &inet6_dgram_ops,
 191         .flags =     INET_PROTOSW_REUSE,
 192 };
 193
 194 #ifdef CONFIG_PROC_FS
 195 static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
 196 {
 197         return ping_seq_start(seq, pos, AF_INET6);
 198 }
 199
 200 static int ping_v6_seq_show(struct seq_file *seq, void *v)
 201 {
 202         if (v == SEQ_START_TOKEN) {
 203                 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
 204         } else {
 205                 int bucket = ((struct ping_iter_state *) seq->private)->bucket;
 206                 struct inet_sock *inet = inet_sk(v);
 207                 __u16 srcp = ntohs(inet->inet_sport);
 208                 __u16 destp = ntohs(inet->inet_dport);
 209                 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
 210         }
 211         return 0;
 212 }
 213
 214 static struct ping_seq_afinfo ping_v6_seq_afinfo = {
 215         .name           = "icmp6",
 216         .family         = AF_INET6,
 217         .seq_fops       = &ping_seq_fops,
 218         .seq_ops        = {
 219                 .start          = ping_v6_seq_start,
 220                 .show           = ping_v6_seq_show,
 221                 .next           = ping_seq_next,
 222                 .stop           = ping_seq_stop,
 223         },
 224 };
 225
 226 static int __net_init ping_v6_proc_init_net(struct net *net)
 227 {
 228         return ping_proc_register(net, &ping_v6_seq_afinfo);
 229 }
 230
 231 static void __net_init ping_v6_proc_exit_net(struct net *net)
 232 {
 233         return ping_proc_unregister(net, &ping_v6_seq_afinfo);
 234 }
 235
 236 static struct pernet_operations ping_v6_net_ops = {
 237         .init = ping_v6_proc_init_net,
 238         .exit = ping_v6_proc_exit_net,
 239 };
 240 #endif
 241
 242 int __init pingv6_init(void)
 243 {
 244 #ifdef CONFIG_PROC_FS
 245         int ret = register_pernet_subsys(&ping_v6_net_ops);
 246         if (ret)
 247                 return ret;
 248 #endif
 249         pingv6_ops.ipv6_recv_error = ipv6_recv_error;
 250         pingv6_ops.ip6_datagram_recv_common_ctl = ip6_datagram_recv_common_ctl;
 251         pingv6_ops.ip6_datagram_recv_specific_ctl =
 252                 ip6_datagram_recv_specific_ctl;
 253         pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
 254         pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
 255         pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
 256         return inet6_register_protosw(&pingv6_protosw);
 257 }
 258
 259 /* This never gets called because it's not possible to unload the ipv6 module,
 260  * but just in case.
 261  */
 262 void pingv6_exit(void)
 263 {
 264         pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
 265         pingv6_ops.ip6_datagram_recv_common_ctl = dummy_ip6_datagram_recv_ctl;
 266         pingv6_ops.ip6_datagram_recv_specific_ctl = dummy_ip6_datagram_recv_ctl;
 267         pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
 268         pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
 269         pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
 270 #ifdef CONFIG_PROC_FS
 271         unregister_pernet_subsys(&ping_v6_net_ops);
 272 #endif
 273         inet6_unregister_protosw(&pingv6_protosw);
 274 }