1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * "Ping" sockets 8 * 9 * Based on ipv4/ping.c code. 10 * 11 * Authors: Lorenzo Colitti (IPv6 support) 12 * Vasiliy Kulikov / Openwall (IPv4 implementation, for Linux 2.6), 13 * Pavel Kankovsky (IPv4 implementation, for Linux 2.4.32) 14 */ 15 16 #include <net/addrconf.h> 17 #include <net/ipv6.h> 18 #include <net/ip6_route.h> 19 #include <net/protocol.h> 20 #include <net/udp.h> 21 #include <net/transp_v6.h> 22 #include <linux/proc_fs.h> 23 #include <linux/bpf-cgroup.h> 24 #include <net/ping.h> 25 26 static void ping_v6_destroy(struct sock *sk) 27 { 28 inet6_destroy_sock(sk); 29 } 30 31 /* Compatibility glue so we can support IPv6 when it's compiled as a module */ 32 static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, 33 int *addr_len) 34 { 35 return -EAFNOSUPPORT; 36 } 37 static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg, 38 struct sk_buff *skb) 39 { 40 } 41 static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err) 42 { 43 return -EAFNOSUPPORT; 44 } 45 static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, 46 __be16 port, u32 info, u8 *payload) {} 47 static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr, 48 const struct net_device *dev, int strict) 49 { 50 return 0; 51 } 52 53 static int ping_v6_pre_connect(struct sock *sk, struct sockaddr *uaddr, 54 int addr_len) 55 { 56 /* This check is replicated from __ip6_datagram_connect() and 57 * intended to prevent BPF program called below from accessing 58 * bytes that are out of the bound specified by user in addr_len. 59 */ 60 61 if (addr_len < SIN6_LEN_RFC2133) 62 return -EINVAL; 63 64 return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr); 65 } 66 67 static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) 68 { 69 struct inet_sock *inet = inet_sk(sk); 70 struct ipv6_pinfo *np = inet6_sk(sk); 71 struct icmp6hdr user_icmph; 72 int addr_type; 73 struct in6_addr *daddr; 74 int oif = 0; 75 struct flowi6 fl6; 76 int err; 77 struct dst_entry *dst; 78 struct rt6_info *rt; 79 struct pingfakehdr pfh; 80 struct ipcm6_cookie ipc6; 81 82 err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph, 83 sizeof(user_icmph)); 84 if (err) 85 return err; 86 87 memset(&fl6, 0, sizeof(fl6)); 88 89 if (msg->msg_name) { 90 DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name); 91 if (msg->msg_namelen < sizeof(*u)) 92 return -EINVAL; 93 if (u->sin6_family != AF_INET6) { 94 return -EAFNOSUPPORT; 95 } 96 daddr = &(u->sin6_addr); 97 if (np->sndflow) 98 fl6.flowlabel = u->sin6_flowinfo & IPV6_FLOWINFO_MASK; 99 if (__ipv6_addr_needs_scope_id(ipv6_addr_type(daddr))) 100 oif = u->sin6_scope_id; 101 } else { 102 if (sk->sk_state != TCP_ESTABLISHED) 103 return -EDESTADDRREQ; 104 daddr = &sk->sk_v6_daddr; 105 fl6.flowlabel = np->flow_label; 106 } 107 108 if (!oif) 109 oif = sk->sk_bound_dev_if; 110 111 if (!oif) 112 oif = np->sticky_pktinfo.ipi6_ifindex; 113 114 if (!oif && ipv6_addr_is_multicast(daddr)) 115 oif = np->mcast_oif; 116 else if (!oif) 117 oif = np->ucast_oif; 118 119 addr_type = ipv6_addr_type(daddr); 120 if ((__ipv6_addr_needs_scope_id(addr_type) && !oif) || 121 (addr_type & IPV6_ADDR_MAPPED) || 122 (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if)) 123 return -EINVAL; 124 125 ipcm6_init_sk(&ipc6, np); 126 ipc6.sockc.tsflags = sk->sk_tsflags; 127 ipc6.sockc.mark = sk->sk_mark; 128 129 fl6.flowi6_oif = oif; 130 131 if (msg->msg_controllen) { 132 struct ipv6_txoptions opt = {}; 133 134 opt.tot_len = sizeof(opt); 135 ipc6.opt = &opt; 136 137 err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, &ipc6); 138 if (err < 0) 139 return err; 140 141 /* Changes to txoptions and flow info are not implemented, yet. 142 * Drop the options. 143 */ 144 ipc6.opt = NULL; 145 } 146 147 fl6.flowi6_proto = IPPROTO_ICMPV6; 148 fl6.saddr = np->saddr; 149 fl6.daddr = *daddr; 150 fl6.flowi6_mark = ipc6.sockc.mark; 151 fl6.flowi6_uid = sk->sk_uid; 152 fl6.fl6_icmp_type = user_icmph.icmp6_type; 153 fl6.fl6_icmp_code = user_icmph.icmp6_code; 154 security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6)); 155 156 fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel); 157 158 dst = ip6_sk_dst_lookup_flow(sk, &fl6, daddr, false); 159 if (IS_ERR(dst)) 160 return PTR_ERR(dst); 161 rt = (struct rt6_info *) dst; 162 163 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr)) 164 fl6.flowi6_oif = np->mcast_oif; 165 else if (!fl6.flowi6_oif) 166 fl6.flowi6_oif = np->ucast_oif; 167 168 pfh.icmph.type = user_icmph.icmp6_type; 169 pfh.icmph.code = user_icmph.icmp6_code; 170 pfh.icmph.checksum = 0; 171 pfh.icmph.un.echo.id = inet->inet_sport; 172 pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence; 173 pfh.msg = msg; 174 pfh.wcheck = 0; 175 pfh.family = AF_INET6; 176 177 if (ipc6.hlimit < 0) 178 ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst); 179 180 lock_sock(sk); 181 err = ip6_append_data(sk, ping_getfrag, &pfh, len, 182 sizeof(struct icmp6hdr), &ipc6, &fl6, rt, 183 MSG_DONTWAIT); 184 185 if (err) { 186 ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev, 187 ICMP6_MIB_OUTERRORS); 188 ip6_flush_pending_frames(sk); 189 } else { 190 icmpv6_push_pending_frames(sk, &fl6, 191 (struct icmp6hdr *)&pfh.icmph, len); 192 } 193 release_sock(sk); 194 195 dst_release(dst); 196 197 if (err) 198 return err; 199 200 return len; 201 } 202 203 struct proto pingv6_prot = { 204 .name = "PINGv6", 205 .owner = THIS_MODULE, 206 .init = ping_init_sock, 207 .close = ping_close, 208 .destroy = ping_v6_destroy, 209 .pre_connect = ping_v6_pre_connect, 210 .connect = ip6_datagram_connect_v6_only, 211 .disconnect = __udp_disconnect, 212 .setsockopt = ipv6_setsockopt, 213 .getsockopt = ipv6_getsockopt, 214 .sendmsg = ping_v6_sendmsg, 215 .recvmsg = ping_recvmsg, 216 .bind = ping_bind, 217 .backlog_rcv = ping_queue_rcv_skb, 218 .hash = ping_hash, 219 .unhash = ping_unhash, 220 .get_port = ping_get_port, 221 .put_port = ping_unhash, 222 .obj_size = sizeof(struct raw6_sock), 223 }; 224 EXPORT_SYMBOL_GPL(pingv6_prot); 225 226 static struct inet_protosw pingv6_protosw = { 227 .type = SOCK_DGRAM, 228 .protocol = IPPROTO_ICMPV6, 229 .prot = &pingv6_prot, 230 .ops = &inet6_sockraw_ops, 231 .flags = INET_PROTOSW_REUSE, 232 }; 233 234 #ifdef CONFIG_PROC_FS 235 static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos) 236 { 237 return ping_seq_start(seq, pos, AF_INET6); 238 } 239 240 static int ping_v6_seq_show(struct seq_file *seq, void *v) 241 { 242 if (v == SEQ_START_TOKEN) { 243 seq_puts(seq, IPV6_SEQ_DGRAM_HEADER); 244 } else { 245 int bucket = ((struct ping_iter_state *) seq->private)->bucket; 246 struct inet_sock *inet = inet_sk(v); 247 __u16 srcp = ntohs(inet->inet_sport); 248 __u16 destp = ntohs(inet->inet_dport); 249 ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket); 250 } 251 return 0; 252 } 253 254 static const struct seq_operations ping_v6_seq_ops = { 255 .start = ping_v6_seq_start, 256 .show = ping_v6_seq_show, 257 .next = ping_seq_next, 258 .stop = ping_seq_stop, 259 }; 260 261 static int __net_init ping_v6_proc_init_net(struct net *net) 262 { 263 if (!proc_create_net("icmp6", 0444, net->proc_net, &ping_v6_seq_ops, 264 sizeof(struct ping_iter_state))) 265 return -ENOMEM; 266 return 0; 267 } 268 269 static void __net_exit ping_v6_proc_exit_net(struct net *net) 270 { 271 remove_proc_entry("icmp6", net->proc_net); 272 } 273 274 static struct pernet_operations ping_v6_net_ops = { 275 .init = ping_v6_proc_init_net, 276 .exit = ping_v6_proc_exit_net, 277 }; 278 #endif 279 280 int __init pingv6_init(void) 281 { 282 #ifdef CONFIG_PROC_FS 283 int ret = register_pernet_subsys(&ping_v6_net_ops); 284 if (ret) 285 return ret; 286 #endif 287 pingv6_ops.ipv6_recv_error = ipv6_recv_error; 288 pingv6_ops.ip6_datagram_recv_common_ctl = ip6_datagram_recv_common_ctl; 289 pingv6_ops.ip6_datagram_recv_specific_ctl = 290 ip6_datagram_recv_specific_ctl; 291 pingv6_ops.icmpv6_err_convert = icmpv6_err_convert; 292 pingv6_ops.ipv6_icmp_error = ipv6_icmp_error; 293 pingv6_ops.ipv6_chk_addr = ipv6_chk_addr; 294 return inet6_register_protosw(&pingv6_protosw); 295 } 296 297 /* This never gets called because it's not possible to unload the ipv6 module, 298 * but just in case. 299 */ 300 void pingv6_exit(void) 301 { 302 pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error; 303 pingv6_ops.ip6_datagram_recv_common_ctl = dummy_ip6_datagram_recv_ctl; 304 pingv6_ops.ip6_datagram_recv_specific_ctl = dummy_ip6_datagram_recv_ctl; 305 pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert; 306 pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error; 307 pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr; 308 #ifdef CONFIG_PROC_FS 309 unregister_pernet_subsys(&ping_v6_net_ops); 310 #endif 311 inet6_unregister_protosw(&pingv6_protosw); 312 } 313