net: ipv6: Add IPv6 support to the ping socket.
This adds the ability to send ICMPv6 echo requests without a
raw socket. The equivalent ability for ICMPv4 was added in
2011.
Instead of having separate code paths for IPv4 and IPv6, make
most of the code in net/ipv4/ping.c dual-stack and only add a
few IPv6-specific bits (like the protocol definition) to a new
net/ipv6/ping.c. Hopefully this will reduce divergence and/or
duplication of bugs in the future.
Caveats:
- Setting options via ancillary data (e.g., using IPV6_PKTINFO
to specify the outgoing interface) is not yet supported.
- There are no separate security settings for IPv4 and IPv6;
everything is controlled by /proc/net/ipv4/ping_group_range.
- The proc interface does not yet display IPv6 ping sockets
properly.
Tested with a patched copy of ping6 and using raw socket calls.
Compiles and works with all of CONFIG_IPV6={n,m,y}.
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ping.c b/net/ipv6/ping.c
new file mode 100644
index 0000000..a6462d6
--- /dev/null
+++ b/net/ipv6/ping.c
@@ -0,0 +1,216 @@
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * "Ping" sockets
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Based on ipv4/ping.c code.
+ *
+ * Authors: Lorenzo Colitti (IPv6 support)
+ * Vasiliy Kulikov / Openwall (IPv4 implementation, for Linux 2.6),
+ * Pavel Kankovsky (IPv4 implementation, for Linux 2.4.32)
+ *
+ */
+
+#include <net/addrconf.h>
+#include <net/ipv6.h>
+#include <net/ip6_route.h>
+#include <net/protocol.h>
+#include <net/udp.h>
+#include <net/transp_v6.h>
+#include <net/ping.h>
+
+struct proto pingv6_prot = {
+ .name = "PINGv6",
+ .owner = THIS_MODULE,
+ .init = ping_init_sock,
+ .close = ping_close,
+ .connect = ip6_datagram_connect,
+ .disconnect = udp_disconnect,
+ .setsockopt = ipv6_setsockopt,
+ .getsockopt = ipv6_getsockopt,
+ .sendmsg = ping_v6_sendmsg,
+ .recvmsg = ping_recvmsg,
+ .bind = ping_bind,
+ .backlog_rcv = ping_queue_rcv_skb,
+ .hash = ping_hash,
+ .unhash = ping_unhash,
+ .get_port = ping_get_port,
+ .obj_size = sizeof(struct raw6_sock),
+};
+EXPORT_SYMBOL_GPL(pingv6_prot);
+
+static struct inet_protosw pingv6_protosw = {
+ .type = SOCK_DGRAM,
+ .protocol = IPPROTO_ICMPV6,
+ .prot = &pingv6_prot,
+ .ops = &inet6_dgram_ops,
+ .no_check = UDP_CSUM_DEFAULT,
+ .flags = INET_PROTOSW_REUSE,
+};
+
+
+/* Compatibility glue so we can support IPv6 when it's compiled as a module */
+int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
+{
+ return -EAFNOSUPPORT;
+}
+int dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
+ struct sk_buff *skb)
+{
+ return -EAFNOSUPPORT;
+}
+int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
+{
+ return -EAFNOSUPPORT;
+}
+void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
+ __be16 port, u32 info, u8 *payload) {}
+int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
+ struct net_device *dev, int strict)
+{
+ return 0;
+}
+
+int __init pingv6_init(void)
+{
+ pingv6_ops.ipv6_recv_error = ipv6_recv_error;
+ pingv6_ops.ip6_datagram_recv_ctl = ip6_datagram_recv_ctl;
+ pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
+ pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
+ pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
+ return inet6_register_protosw(&pingv6_protosw);
+}
+
+/* This never gets called because it's not possible to unload the ipv6 module,
+ * but just in case.
+ */
+void pingv6_exit(void)
+{
+ pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
+ pingv6_ops.ip6_datagram_recv_ctl = dummy_ip6_datagram_recv_ctl;
+ pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
+ pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
+ pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
+ inet6_unregister_protosw(&pingv6_protosw);
+}
+
+int ping_v6_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
+ size_t len)
+{
+ struct inet_sock *inet = inet_sk(sk);
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct icmp6hdr user_icmph;
+ int addr_type;
+ struct in6_addr *daddr;
+ int iif = 0;
+ struct flowi6 fl6;
+ int err;
+ int hlimit;
+ struct dst_entry *dst;
+ struct rt6_info *rt;
+ struct pingfakehdr pfh;
+
+ pr_debug("ping_v6_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
+
+ err = ping_common_sendmsg(AF_INET6, msg, len, &user_icmph,
+ sizeof(user_icmph));
+ if (err)
+ return err;
+
+ if (msg->msg_name) {
+ struct sockaddr_in6 *u = (struct sockaddr_in6 *) msg->msg_name;
+ if (msg->msg_namelen < sizeof(struct sockaddr_in6) ||
+ u->sin6_family != AF_INET6) {
+ return -EINVAL;
+ }
+ if (sk->sk_bound_dev_if &&
+ sk->sk_bound_dev_if != u->sin6_scope_id) {
+ return -EINVAL;
+ }
+ daddr = &(u->sin6_addr);
+ iif = u->sin6_scope_id;
+ } else {
+ if (sk->sk_state != TCP_ESTABLISHED)
+ return -EDESTADDRREQ;
+ daddr = &np->daddr;
+ }
+
+ if (!iif)
+ iif = sk->sk_bound_dev_if;
+
+ addr_type = ipv6_addr_type(daddr);
+ if (__ipv6_addr_needs_scope_id(addr_type) && !iif)
+ return -EINVAL;
+ if (addr_type & IPV6_ADDR_MAPPED)
+ return -EINVAL;
+
+ /* TODO: use ip6_datagram_send_ctl to get options from cmsg */
+
+ memset(&fl6, 0, sizeof(fl6));
+
+ fl6.flowi6_proto = IPPROTO_ICMPV6;
+ fl6.saddr = np->saddr;
+ fl6.daddr = *daddr;
+ fl6.fl6_icmp_type = user_icmph.icmp6_type;
+ fl6.fl6_icmp_code = user_icmph.icmp6_code;
+ security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
+
+ if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
+ fl6.flowi6_oif = np->mcast_oif;
+ else if (!fl6.flowi6_oif)
+ fl6.flowi6_oif = np->ucast_oif;
+
+ dst = ip6_sk_dst_lookup_flow(sk, &fl6, daddr, 1);
+ if (IS_ERR(dst))
+ return PTR_ERR(dst);
+ rt = (struct rt6_info *) dst;
+
+ np = inet6_sk(sk);
+ if (!np)
+ return -EBADF;
+
+ if (!fl6.flowi6_oif && ipv6_addr_is_multicast(&fl6.daddr))
+ fl6.flowi6_oif = np->mcast_oif;
+ else if (!fl6.flowi6_oif)
+ fl6.flowi6_oif = np->ucast_oif;
+
+ pfh.icmph.type = user_icmph.icmp6_type;
+ pfh.icmph.code = user_icmph.icmp6_code;
+ pfh.icmph.checksum = 0;
+ pfh.icmph.un.echo.id = inet->inet_sport;
+ pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
+ pfh.iov = msg->msg_iov;
+ pfh.wcheck = 0;
+ pfh.family = AF_INET6;
+
+ if (ipv6_addr_is_multicast(&fl6.daddr))
+ hlimit = np->mcast_hops;
+ else
+ hlimit = np->hop_limit;
+ if (hlimit < 0)
+ hlimit = ip6_dst_hoplimit(dst);
+
+ err = ip6_append_data(sk, ping_getfrag, &pfh, len,
+ 0, hlimit,
+ np->tclass, NULL, &fl6, rt,
+ MSG_DONTWAIT, np->dontfrag);
+
+ if (err) {
+ ICMP6_INC_STATS_BH(sock_net(sk), rt->rt6i_idev,
+ ICMP6_MIB_OUTERRORS);
+ ip6_flush_pending_frames(sk);
+ } else {
+ err = icmpv6_push_pending_frames(sk, &fl6,
+ (struct icmp6hdr *) &pfh.icmph,
+ len);
+ }
+
+ return err;
+}