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         struct dst_entry *dst;
  62         struct rt6_info *rt;
  63         struct pingfakehdr pfh;
  64         struct sockcm_cookie junk = {0};
  65         struct ipcm6_cookie ipc6;
  66
  67         pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
  68
  69         err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
  70                                   sizeof(user_icmph));
  71         if (err)
  72                 return err;
  73
  74         if (msg->msg_name) {
  75                 DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
  76                 if (msg->msg_namelen < sizeof(*u))
  77                         return -EINVAL;
  78                 if (u->sin6_family != AF_INET6) {
  79                         return -EAFNOSUPPORT;
  80                 }
  81                 if (sk->sk_bound_dev_if &&
  82                     sk->sk_bound_dev_if != u->sin6_scope_id) {
  83                         return -EINVAL;
  84                 }
  85                 daddr = &(u->sin6_addr);
  86                 iif = u->sin6_scope_id;
  87         } else {
  88                 if (sk->sk_state != TCP_ESTABLISHED)
  89                         return -EDESTADDRREQ;
  90                 daddr = &sk->sk_v6_daddr;
  91         }
  92
  93         if (!iif)
  94                 iif = sk->sk_bound_dev_if;
  95
  96         addr_type = ipv6_addr_type(daddr);
  97         if (__ipv6_addr_needs_scope_id(addr_type) && !iif)
  98                 return -EINVAL;
  99         if (addr_type & IPV6_ADDR_MAPPED)
 100                 return -EINVAL;
 101
 102         /* TODO: use ip6_datagram_send_ctl to get options from cmsg */
 103
 104         memset(&fl6, 0, sizeof(fl6));
 105
 106         fl6.flowi6_proto = IPPROTO_ICMPV6;
 107         fl6.saddr = np->saddr;
 108         fl6.daddr = *daddr;
 109         fl6.flowi6_mark = sk->sk_mark;
 110         fl6.fl6_icmp_type = user_icmph.icmp6_type;
 111         fl6.fl6_icmp_code = user_icmph.icmp6_code;
 112         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 113
 114         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 115                 fl6.flowi6_oif = np->mcast_oif;
 116         else if (!fl6.flowi6_oif)
 117                 fl6.flowi6_oif = np->ucast_oif;
 118
 119         dst = ip6_sk_dst_lookup_flow(sk, &fl6,  daddr);
 120         if (IS_ERR(dst))
 121                 return PTR_ERR(dst);
 122         rt = (struct rt6_info *) dst;
 123
 124         np = inet6_sk(sk);
 125         if (!np)
 126                 return -EBADF;
 127
 128         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 129                 fl6.flowi6_oif = np->mcast_oif;
 130         else if (!fl6.flowi6_oif)
 131                 fl6.flowi6_oif = np->ucast_oif;
 132
 133         pfh.icmph.type = user_icmph.icmp6_type;
 134         pfh.icmph.code = user_icmph.icmp6_code;
 135         pfh.icmph.checksum = 0;
 136         pfh.icmph.un.echo.id = inet->inet_sport;
 137         pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
 138         pfh.msg = msg;
 139         pfh.wcheck = 0;
 140         pfh.family = AF_INET6;
 141
 142         ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 143         ipc6.tclass = np->tclass;
 144         ipc6.dontfrag = np->dontfrag;
 145         ipc6.opt = NULL;
 146
 147         lock_sock(sk);
 148         err = ip6_append_data(sk, ping_getfrag, &pfh, len,
 149                               0, &ipc6, &fl6, rt,
 150                               MSG_DONTWAIT, &junk);
 151
 152         if (err) {
 153                 ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
 154                                 ICMP6_MIB_OUTERRORS);
 155                 ip6_flush_pending_frames(sk);
 156         } else {
 157                 err = icmpv6_push_pending_frames(sk, &fl6,
 158                                                  (struct icmp6hdr *) &pfh.icmph,
 159                                                  len);
 160         }
 161         release_sock(sk);
 162
 163         if (err)
 164                 return err;
 165
 166         return len;
 167 }
 168
 169 struct proto pingv6_prot = {
 170         .name =         "PINGv6",
 171         .owner =        THIS_MODULE,
 172         .init =         ping_init_sock,
 173         .close =        ping_close,
 174         .connect =      ip6_datagram_connect_v6_only,
 175         .disconnect =   udp_disconnect,
 176         .setsockopt =   ipv6_setsockopt,
 177         .getsockopt =   ipv6_getsockopt,
 178         .sendmsg =      ping_v6_sendmsg,
 179         .recvmsg =      ping_recvmsg,
 180         .bind =         ping_bind,
 181         .backlog_rcv =  ping_queue_rcv_skb,
 182         .hash =         ping_hash,
 183         .unhash =       ping_unhash,
 184         .get_port =     ping_get_port,
 185         .obj_size =     sizeof(struct raw6_sock),
 186 };
 187 EXPORT_SYMBOL_GPL(pingv6_prot);
 188
 189 static struct inet_protosw pingv6_protosw = {
 190         .type =      SOCK_DGRAM,
 191         .protocol =  IPPROTO_ICMPV6,
 192         .prot =      &pingv6_prot,
 193         .ops =       &inet6_dgram_ops,
 194         .flags =     INET_PROTOSW_REUSE,
 195 };
 196
 197 #ifdef CONFIG_PROC_FS
 198 static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
 199 {
 200         return ping_seq_start(seq, pos, AF_INET6);
 201 }
 202
 203 static int ping_v6_seq_show(struct seq_file *seq, void *v)
 204 {
 205         if (v == SEQ_START_TOKEN) {
 206                 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
 207         } else {
 208                 int bucket = ((struct ping_iter_state *) seq->private)->bucket;
 209                 struct inet_sock *inet = inet_sk(v);
 210                 __u16 srcp = ntohs(inet->inet_sport);
 211                 __u16 destp = ntohs(inet->inet_dport);
 212                 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
 213         }
 214         return 0;
 215 }
 216
 217 static struct ping_seq_afinfo ping_v6_seq_afinfo = {
 218         .name           = "icmp6",
 219         .family         = AF_INET6,
 220         .seq_fops       = &ping_seq_fops,
 221         .seq_ops        = {
 222                 .start          = ping_v6_seq_start,
 223                 .show           = ping_v6_seq_show,
 224                 .next           = ping_seq_next,
 225                 .stop           = ping_seq_stop,
 226         },
 227 };
 228
 229 static int __net_init ping_v6_proc_init_net(struct net *net)
 230 {
 231         return ping_proc_register(net, &ping_v6_seq_afinfo);
 232 }
 233
 234 static void __net_init ping_v6_proc_exit_net(struct net *net)
 235 {
 236         return ping_proc_unregister(net, &ping_v6_seq_afinfo);
 237 }
 238
 239 static struct pernet_operations ping_v6_net_ops = {
 240         .init = ping_v6_proc_init_net,
 241         .exit = ping_v6_proc_exit_net,
 242 };
 243 #endif
 244
 245 int __init pingv6_init(void)
 246 {
 247 #ifdef CONFIG_PROC_FS
 248         int ret = register_pernet_subsys(&ping_v6_net_ops);
 249         if (ret)
 250                 return ret;
 251 #endif
 252         pingv6_ops.ipv6_recv_error = ipv6_recv_error;
 253         pingv6_ops.ip6_datagram_recv_common_ctl = ip6_datagram_recv_common_ctl;
 254         pingv6_ops.ip6_datagram_recv_specific_ctl =
 255                 ip6_datagram_recv_specific_ctl;
 256         pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
 257         pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
 258         pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
 259         return inet6_register_protosw(&pingv6_protosw);
 260 }
 261
 262 /* This never gets called because it's not possible to unload the ipv6 module,
 263  * but just in case.
 264  */
 265 void pingv6_exit(void)
 266 {
 267         pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
 268         pingv6_ops.ip6_datagram_recv_common_ctl = dummy_ip6_datagram_recv_ctl;
 269         pingv6_ops.ip6_datagram_recv_specific_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 }