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 /* Compatibility glue so we can support IPv6 when it's compiled as a module */
  31 static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
  32                                  int *addr_len)
  33 {
  34         return -EAFNOSUPPORT;
  35 }
  36 static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
  37                                        struct sk_buff *skb)
  38 {
  39 }
  40 static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
  41 {
  42         return -EAFNOSUPPORT;
  43 }
  44 static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
  45                                   __be16 port, u32 info, u8 *payload) {}
  46 static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
  47                                const struct net_device *dev, int strict)
  48 {
  49         return 0;
  50 }
  51
  52 static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
  53 {
  54         struct inet_sock *inet = inet_sk(sk);
  55         struct ipv6_pinfo *np = inet6_sk(sk);
  56         struct icmp6hdr user_icmph;
  57         int addr_type;
  58         struct in6_addr *daddr;
  59         int oif = 0;
  60         struct flowi6 fl6;
  61         int err;
  62         struct dst_entry *dst;
  63         struct rt6_info *rt;
  64         struct pingfakehdr pfh;
  65         struct sockcm_cookie junk = {0};
  66         struct ipcm6_cookie ipc6;
  67
  68         pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
  69
  70         err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
  71                                   sizeof(user_icmph));
  72         if (err)
  73                 return err;
  74
  75         if (msg->msg_name) {
  76                 DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
  77                 if (msg->msg_namelen < sizeof(*u))
  78                         return -EINVAL;
  79                 if (u->sin6_family != AF_INET6) {
  80                         return -EAFNOSUPPORT;
  81                 }
  82                 daddr = &(u->sin6_addr);
  83                 if (__ipv6_addr_needs_scope_id(ipv6_addr_type(daddr)))
  84                         oif = u->sin6_scope_id;
  85         } else {
  86                 if (sk->sk_state != TCP_ESTABLISHED)
  87                         return -EDESTADDRREQ;
  88                 daddr = &sk->sk_v6_daddr;
  89         }
  90
  91         if (!oif)
  92                 oif = sk->sk_bound_dev_if;
  93
  94         if (!oif)
  95                 oif = np->sticky_pktinfo.ipi6_ifindex;
  96
  97         if (!oif && ipv6_addr_is_multicast(daddr))
  98                 oif = np->mcast_oif;
  99         else if (!oif)
 100                 oif = np->ucast_oif;
 101
 102         addr_type = ipv6_addr_type(daddr);
 103         if ((__ipv6_addr_needs_scope_id(addr_type) && !oif) ||
 104             (addr_type & IPV6_ADDR_MAPPED) ||
 105             (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if))
 106                 return -EINVAL;
 107
 108         /* TODO: use ip6_datagram_send_ctl to get options from cmsg */
 109
 110         memset(&fl6, 0, sizeof(fl6));
 111
 112         fl6.flowi6_proto = IPPROTO_ICMPV6;
 113         fl6.saddr = np->saddr;
 114         fl6.daddr = *daddr;
 115         fl6.flowi6_oif = oif;
 116         fl6.flowi6_mark = sk->sk_mark;
 117         fl6.flowi6_uid = sk->sk_uid;
 118         fl6.fl6_icmp_type = user_icmph.icmp6_type;
 119         fl6.fl6_icmp_code = user_icmph.icmp6_code;
 120         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
 121
 122         ipc6.tclass = np->tclass;
 123         fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
 124
 125         dst = ip6_sk_dst_lookup_flow(sk, &fl6, daddr, false);
 126         if (IS_ERR(dst))
 127                 return PTR_ERR(dst);
 128         rt = (struct rt6_info *) dst;
 129
 130         if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
 131                 fl6.flowi6_oif = np->mcast_oif;
 132         else if (!fl6.flowi6_oif)
 133                 fl6.flowi6_oif = np->ucast_oif;
 134
 135         pfh.icmph.type = user_icmph.icmp6_type;
 136         pfh.icmph.code = user_icmph.icmp6_code;
 137         pfh.icmph.checksum = 0;
 138         pfh.icmph.un.echo.id = inet->inet_sport;
 139         pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
 140         pfh.msg = msg;
 141         pfh.wcheck = 0;
 142         pfh.family = AF_INET6;
 143
 144         ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 145         ipc6.dontfrag = np->dontfrag;
 146         ipc6.opt = NULL;
 147
 148         lock_sock(sk);
 149         err = ip6_append_data(sk, ping_getfrag, &pfh, len,
 150                               0, &ipc6, &fl6, rt,
 151                               MSG_DONTWAIT, &junk);
 152
 153         if (err) {
 154                 ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
 155                                 ICMP6_MIB_OUTERRORS);
 156                 ip6_flush_pending_frames(sk);
 157         } else {
 158                 icmpv6_push_pending_frames(sk, &fl6,
 159                                            (struct icmp6hdr *)&pfh.icmph, len);
 160         }
 161         release_sock(sk);
 162
 163         dst_release(dst);
 164
 165         if (err)
 166                 return err;
 167
 168         return len;
 169 }
 170
 171 struct proto pingv6_prot = {
 172         .name =         "PINGv6",
 173         .owner =        THIS_MODULE,
 174         .init =         ping_init_sock,
 175         .close =        ping_close,
 176         .connect =      ip6_datagram_connect_v6_only,
 177         .disconnect =   __udp_disconnect,
 178         .setsockopt =   ipv6_setsockopt,
 179         .getsockopt =   ipv6_getsockopt,
 180         .sendmsg =      ping_v6_sendmsg,
 181         .recvmsg =      ping_recvmsg,
 182         .bind =         ping_bind,
 183         .backlog_rcv =  ping_queue_rcv_skb,
 184         .hash =         ping_hash,
 185         .unhash =       ping_unhash,
 186         .get_port =     ping_get_port,
 187         .obj_size =     sizeof(struct raw6_sock),
 188 };
 189 EXPORT_SYMBOL_GPL(pingv6_prot);
 190
 191 static struct inet_protosw pingv6_protosw = {
 192         .type =      SOCK_DGRAM,
 193         .protocol =  IPPROTO_ICMPV6,
 194         .prot =      &pingv6_prot,
 195         .ops =       &inet6_sockraw_ops,
 196         .flags =     INET_PROTOSW_REUSE,
 197 };
 198
 199 #ifdef CONFIG_PROC_FS
 200 static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
 201 {
 202         return ping_seq_start(seq, pos, AF_INET6);
 203 }
 204
 205 static int ping_v6_seq_show(struct seq_file *seq, void *v)
 206 {
 207         if (v == SEQ_START_TOKEN) {
 208                 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
 209         } else {
 210                 int bucket = ((struct ping_iter_state *) seq->private)->bucket;
 211                 struct inet_sock *inet = inet_sk(v);
 212                 __u16 srcp = ntohs(inet->inet_sport);
 213                 __u16 destp = ntohs(inet->inet_dport);
 214                 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
 215         }
 216         return 0;
 217 }
 218
 219 static const struct seq_operations ping_v6_seq_ops = {
 220         .start          = ping_v6_seq_start,
 221         .show           = ping_v6_seq_show,
 222         .next           = ping_seq_next,
 223         .stop           = ping_seq_stop,
 224 };
 225
 226 static int __net_init ping_v6_proc_init_net(struct net *net)
 227 {
 228         if (!proc_create_net("icmp6", 0444, net->proc_net, &ping_v6_seq_ops,
 229                         sizeof(struct ping_iter_state)))
 230                 return -ENOMEM;
 231         return 0;
 232 }
 233
 234 static void __net_init ping_v6_proc_exit_net(struct net *net)
 235 {
 236         remove_proc_entry("icmp6", net->proc_net);
 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 }