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 <linux/proc_fs.h>
  28 #include <net/ping.h>
  29
  30 static void ping_v6_destroy(struct sock *sk)
  31 {
  32         inet6_destroy_sock(sk);
  33 }
  34
  35 /* Compatibility glue so we can support IPv6 when it's compiled as a module */
  36 static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
  37                                  int *addr_len)
  38 {
  39         return -EAFNOSUPPORT;
  40 }
  41 static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
  42                                        struct sk_buff *skb)
  43 {
  44 }
  45 static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
  46 {
  47         return -EAFNOSUPPORT;
  48 }
  49 static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
  50                                   __be16 port, u32 info, u8 *payload) {}
  51 static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
  52                                const struct net_device *dev, int strict)
  53 {
  54         return 0;
  55 }
  56
  57 static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
  58 {
  59         struct inet_sock *inet = inet_sk(sk);
  60         struct ipv6_pinfo *np = inet6_sk(sk);
  61         struct icmp6hdr user_icmph;
  62         int addr_type;
  63         struct in6_addr *daddr;
  64         int oif = 0;
  65         struct flowi6 fl6;
  66         int err;
  67         struct dst_entry *dst;
  68         struct rt6_info *rt;
  69         struct pingfakehdr pfh;
  70         struct ipcm6_cookie ipc6;
  71
  72         pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
  73
  74         err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
  75                                   sizeof(user_icmph));
  76         if (err)
  77                 return err;
  78
  79         if (msg->msg_name) {
  80                 DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
  81                 if (msg->msg_namelen < sizeof(*u))
  82                         return -EINVAL;
  83                 if (u->sin6_family != AF_INET6) {
  84                         return -EAFNOSUPPORT;
  85                 }
  86                 daddr = &(u->sin6_addr);
  87                 if (__ipv6_addr_needs_scope_id(ipv6_addr_type(daddr)))
  88                         oif = u->sin6_scope_id;
  89         } else {
  90                 if (sk->sk_state != TCP_ESTABLISHED)
  91                         return -EDESTADDRREQ;
  92                 daddr = &sk->sk_v6_daddr;
  93         }
  94
  95         if (!oif)
  96                 oif = sk->sk_bound_dev_if;
  97
  98         if (!oif)
  99                 oif = np->sticky_pktinfo.ipi6_ifindex;
 100
 101         if (!oif && ipv6_addr_is_multicast(daddr))
 102                 oif = np->mcast_oif;
 103         else if (!oif)
 104                 oif = np->ucast_oif;
 105
 106         addr_type = ipv6_addr_type(daddr);
 107         if ((__ipv6_addr_needs_scope_id(addr_type) && !oif) ||
 108             (addr_type & IPV6_ADDR_MAPPED) ||
 109             (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if))
 110                 return -EINVAL;
 111
 112         /* TODO: use ip6_datagram_send_ctl to get options from cmsg */
 113
 114         memset(&fl6, 0, sizeof(fl6));
 115
 116         fl6.flowi6_proto = IPPROTO_ICMPV6;
 117         fl6.saddr = np->saddr;
 118         fl6.daddr = *daddr;
 119         fl6.flowi6_oif = oif;
 120         fl6.flowi6_mark = sk->sk_mark;
 121         fl6.flowi6_uid = sk->sk_uid;
 122         fl6.fl6_icmp_type = user_icmph.icmp6_type;
 123         fl6.fl6_icmp_code = user_icmph.icmp6_code;
 124         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 125
 126         ipcm6_init_sk(&ipc6, np);
 127         fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
 128
 129         dst = ip6_sk_dst_lookup_flow(sk, &fl6, daddr, false);
 130         if (IS_ERR(dst))
 131                 return PTR_ERR(dst);
 132         rt = (struct rt6_info *) dst;
 133
 134         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 135                 fl6.flowi6_oif = np->mcast_oif;
 136         else if (!fl6.flowi6_oif)
 137                 fl6.flowi6_oif = np->ucast_oif;
 138
 139         pfh.icmph.type = user_icmph.icmp6_type;
 140         pfh.icmph.code = user_icmph.icmp6_code;
 141         pfh.icmph.checksum = 0;
 142         pfh.icmph.un.echo.id = inet->inet_sport;
 143         pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
 144         pfh.msg = msg;
 145         pfh.wcheck = 0;
 146         pfh.family = AF_INET6;
 147
 148         ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 149
 150         lock_sock(sk);
 151         err = ip6_append_data(sk, ping_getfrag, &pfh, len,
 152                               0, &ipc6, &fl6, rt,
 153                               MSG_DONTWAIT);
 154
 155         if (err) {
 156                 ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
 157                                 ICMP6_MIB_OUTERRORS);
 158                 ip6_flush_pending_frames(sk);
 159         } else {
 160                 icmpv6_push_pending_frames(sk, &fl6,
 161                                            (struct icmp6hdr *)&pfh.icmph, len);
 162         }
 163         release_sock(sk);
 164
 165         dst_release(dst);
 166
 167         if (err)
 168                 return err;
 169
 170         return len;
 171 }
 172
 173 struct proto pingv6_prot = {
 174         .name =         "PINGv6",
 175         .owner =        THIS_MODULE,
 176         .init =         ping_init_sock,
 177         .close =        ping_close,
 178         .destroy =      ping_v6_destroy,
 179         .connect =      ip6_datagram_connect_v6_only,
 180         .disconnect =   __udp_disconnect,
 181         .setsockopt =   ipv6_setsockopt,
 182         .getsockopt =   ipv6_getsockopt,
 183         .sendmsg =      ping_v6_sendmsg,
 184         .recvmsg =      ping_recvmsg,
 185         .bind =         ping_bind,
 186         .backlog_rcv =  ping_queue_rcv_skb,
 187         .hash =         ping_hash,
 188         .unhash =       ping_unhash,
 189         .get_port =     ping_get_port,
 190         .obj_size =     sizeof(struct raw6_sock),
 191 };
 192 EXPORT_SYMBOL_GPL(pingv6_prot);
 193
 194 static struct inet_protosw pingv6_protosw = {
 195         .type =      SOCK_DGRAM,
 196         .protocol =  IPPROTO_ICMPV6,
 197         .prot =      &pingv6_prot,
 198         .ops =       &inet6_sockraw_ops,
 199         .flags =     INET_PROTOSW_REUSE,
 200 };
 201
 202 #ifdef CONFIG_PROC_FS
 203 static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
 204 {
 205         return ping_seq_start(seq, pos, AF_INET6);
 206 }
 207
 208 static int ping_v6_seq_show(struct seq_file *seq, void *v)
 209 {
 210         if (v == SEQ_START_TOKEN) {
 211                 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
 212         } else {
 213                 int bucket = ((struct ping_iter_state *) seq->private)->bucket;
 214                 struct inet_sock *inet = inet_sk(v);
 215                 __u16 srcp = ntohs(inet->inet_sport);
 216                 __u16 destp = ntohs(inet->inet_dport);
 217                 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
 218         }
 219         return 0;
 220 }
 221
 222 static const struct seq_operations ping_v6_seq_ops = {
 223         .start          = ping_v6_seq_start,
 224         .show           = ping_v6_seq_show,
 225         .next           = ping_seq_next,
 226         .stop           = ping_seq_stop,
 227 };
 228
 229 static int __net_init ping_v6_proc_init_net(struct net *net)
 230 {
 231         if (!proc_create_net("icmp6", 0444, net->proc_net, &ping_v6_seq_ops,
 232                         sizeof(struct ping_iter_state)))
 233                 return -ENOMEM;
 234         return 0;
 235 }
 236
 237 static void __net_exit ping_v6_proc_exit_net(struct net *net)
 238 {
 239         remove_proc_entry("icmp6", net->proc_net);
 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_common_ctl = ip6_datagram_recv_common_ctl;
 257         pingv6_ops.ip6_datagram_recv_specific_ctl =
 258                 ip6_datagram_recv_specific_ctl;
 259         pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
 260         pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
 261         pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
 262         return inet6_register_protosw(&pingv6_protosw);
 263 }
 264
 265 /* This never gets called because it's not possible to unload the ipv6 module,
 266  * but just in case.
 267  */
 268 void pingv6_exit(void)
 269 {
 270         pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
 271         pingv6_ops.ip6_datagram_recv_common_ctl = dummy_ip6_datagram_recv_ctl;
 272         pingv6_ops.ip6_datagram_recv_specific_ctl = dummy_ip6_datagram_recv_ctl;
 273         pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
 274         pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
 275         pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
 276 #ifdef CONFIG_PROC_FS
 277         unregister_pernet_subsys(&ping_v6_net_ops);
 278 #endif
 279         inet6_unregister_protosw(&pingv6_protosw);
 280 }