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_v6_only,
  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         .flags =     INET_PROTOSW_REUSE,
  55 };
  56
  57
  58 /* Compatibility glue so we can support IPv6 when it's compiled as a module */
  59 static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
  60                                  int *addr_len)
  61 {
  62         return -EAFNOSUPPORT;
  63 }
  64 static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
  65                                        struct sk_buff *skb)
  66 {
  67 }
  68 static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
  69 {
  70         return -EAFNOSUPPORT;
  71 }
  72 static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
  73                                   __be16 port, u32 info, u8 *payload) {}
  74 static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
  75                                const struct net_device *dev, int strict)
  76 {
  77         return 0;
  78 }
  79
  80 int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
  81 {
  82         struct inet_sock *inet = inet_sk(sk);
  83         struct ipv6_pinfo *np = inet6_sk(sk);
  84         struct icmp6hdr user_icmph;
  85         int addr_type;
  86         struct in6_addr *daddr;
  87         int oif = 0;
  88         struct flowi6 fl6;
  89         int err;
  90         int hlimit;
  91         struct dst_entry *dst;
  92         struct rt6_info *rt;
  93         struct pingfakehdr pfh;
  94
  95         pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
  96
  97         err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
  98                                   sizeof(user_icmph));
  99         if (err)
 100                 return err;
 101
 102         if (msg->msg_name) {
 103                 DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
 104                 if (msg->msg_namelen < sizeof(*u))
 105                         return -EINVAL;
 106                 if (u->sin6_family != AF_INET6) {
 107                         return -EAFNOSUPPORT;
 108                 }
 109                 daddr = &(u->sin6_addr);
 110                 if (__ipv6_addr_needs_scope_id(ipv6_addr_type(daddr)))
 111                         oif = u->sin6_scope_id;
 112         } else {
 113                 if (sk->sk_state != TCP_ESTABLISHED)
 114                         return -EDESTADDRREQ;
 115                 daddr = &sk->sk_v6_daddr;
 116         }
 117
 118         if (!oif)
 119                 oif = sk->sk_bound_dev_if;
 120
 121         if (!oif)
 122                 oif = np->sticky_pktinfo.ipi6_ifindex;
 123
 124         if (!oif && ipv6_addr_is_multicast(daddr))
 125                 oif = np->mcast_oif;
 126         else if (!oif)
 127                 oif = np->ucast_oif;
 128
 129         addr_type = ipv6_addr_type(daddr);
 130         if ((__ipv6_addr_needs_scope_id(addr_type) && !oif) ||
 131             (addr_type & IPV6_ADDR_MAPPED) ||
 132             (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if))
 133                 return -EINVAL;
 134
 135         /* TODO: use ip6_datagram_send_ctl to get options from cmsg */
 136
 137         memset(&fl6, 0, sizeof(fl6));
 138
 139         fl6.flowi6_proto = IPPROTO_ICMPV6;
 140         fl6.saddr = np->saddr;
 141         fl6.daddr = *daddr;
 142         fl6.flowi6_oif = oif;
 143         fl6.flowi6_mark = sk->sk_mark;
 144         fl6.flowi6_uid = sock_i_uid(sk);
 145         fl6.fl6_icmp_type = user_icmph.icmp6_type;
 146         fl6.fl6_icmp_code = user_icmph.icmp6_code;
 147         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 148
 149         dst = ip6_sk_dst_lookup_flow(sk, &fl6,  daddr);
 150         if (IS_ERR(dst))
 151                 return PTR_ERR(dst);
 152         rt = (struct rt6_info *) dst;
 153
 154         np = inet6_sk(sk);
 155         if (!np) {
 156                 err = -EBADF;
 157                 goto dst_err_out;
 158         }
 159
 160         pfh.icmph.type = user_icmph.icmp6_type;
 161         pfh.icmph.code = user_icmph.icmp6_code;
 162         pfh.icmph.checksum = 0;
 163         pfh.icmph.un.echo.id = inet->inet_sport;
 164         pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
 165         pfh.msg = msg;
 166         pfh.wcheck = 0;
 167         pfh.family = AF_INET6;
 168
 169         hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 170
 171         lock_sock(sk);
 172         err = ip6_append_data(sk, ping_getfrag, &pfh, len,
 173                               0, hlimit,
 174                               np->tclass, NULL, &fl6, rt,
 175                               MSG_DONTWAIT, np->dontfrag);
 176
 177         if (err) {
 178                 ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
 179                                 ICMP6_MIB_OUTERRORS);
 180                 ip6_flush_pending_frames(sk);
 181         } else {
 182                 err = icmpv6_push_pending_frames(sk, &fl6,
 183                                                  (struct icmp6hdr *) &pfh.icmph,
 184                                                  len);
 185         }
 186         release_sock(sk);
 187
 188 dst_err_out:
 189         dst_release(dst);
 190
 191         if (err)
 192                 return err;
 193
 194         return len;
 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 }