alistair23-linux/net/ipv6/ping.c
Paul Moore 3df98d7921 lsm,selinux: pass flowi_common instead of flowi to the LSM hooks
As pointed out by Herbert in a recent related patch, the LSM hooks do
not have the necessary address family information to use the flowi
struct safely.  As none of the LSMs currently use any of the protocol
specific flowi information, replace the flowi pointers with pointers
to the address family independent flowi_common struct.

Reported-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-11-23 18:36:21 -05:00

271 lines
7.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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
*
* 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 <linux/proc_fs.h>
#include <net/ping.h>
/* Compatibility glue so we can support IPv6 when it's compiled as a module */
static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
int *addr_len)
{
return -EAFNOSUPPORT;
}
static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
struct sk_buff *skb)
{
}
static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
{
return -EAFNOSUPPORT;
}
static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
__be16 port, u32 info, u8 *payload) {}
static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
const struct net_device *dev, int strict)
{
return 0;
}
static int ping_v6_sendmsg(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 oif = 0;
struct flowi6 fl6;
int err;
struct dst_entry *dst;
struct rt6_info *rt;
struct pingfakehdr pfh;
struct ipcm6_cookie ipc6;
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) {
DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
if (msg->msg_namelen < sizeof(*u))
return -EINVAL;
if (u->sin6_family != AF_INET6) {
return -EAFNOSUPPORT;
}
daddr = &(u->sin6_addr);
if (__ipv6_addr_needs_scope_id(ipv6_addr_type(daddr)))
oif = u->sin6_scope_id;
} else {
if (sk->sk_state != TCP_ESTABLISHED)
return -EDESTADDRREQ;
daddr = &sk->sk_v6_daddr;
}
if (!oif)
oif = sk->sk_bound_dev_if;
if (!oif)
oif = np->sticky_pktinfo.ipi6_ifindex;
if (!oif && ipv6_addr_is_multicast(daddr))
oif = np->mcast_oif;
else if (!oif)
oif = np->ucast_oif;
addr_type = ipv6_addr_type(daddr);
if ((__ipv6_addr_needs_scope_id(addr_type) && !oif) ||
(addr_type & IPV6_ADDR_MAPPED) ||
(oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if))
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.flowi6_oif = oif;
fl6.flowi6_mark = sk->sk_mark;
fl6.flowi6_uid = sk->sk_uid;
fl6.fl6_icmp_type = user_icmph.icmp6_type;
fl6.fl6_icmp_code = user_icmph.icmp6_code;
security_sk_classify_flow(sk, flowi6_to_flowi_common(&fl6));
ipcm6_init_sk(&ipc6, np);
ipc6.sockc.mark = sk->sk_mark;
fl6.flowlabel = ip6_make_flowinfo(ipc6.tclass, fl6.flowlabel);
dst = ip6_sk_dst_lookup_flow(sk, &fl6, daddr, false);
if (IS_ERR(dst))
return PTR_ERR(dst);
rt = (struct rt6_info *) dst;
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.msg = msg;
pfh.wcheck = 0;
pfh.family = AF_INET6;
ipc6.hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
lock_sock(sk);
err = ip6_append_data(sk, ping_getfrag, &pfh, len,
0, &ipc6, &fl6, rt,
MSG_DONTWAIT);
if (err) {
ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
ICMP6_MIB_OUTERRORS);
ip6_flush_pending_frames(sk);
} else {
icmpv6_push_pending_frames(sk, &fl6,
(struct icmp6hdr *)&pfh.icmph, len);
}
release_sock(sk);
dst_release(dst);
if (err)
return err;
return len;
}
struct proto pingv6_prot = {
.name = "PINGv6",
.owner = THIS_MODULE,
.init = ping_init_sock,
.close = ping_close,
.connect = ip6_datagram_connect_v6_only,
.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_sockraw_ops,
.flags = INET_PROTOSW_REUSE,
};
#ifdef CONFIG_PROC_FS
static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
{
return ping_seq_start(seq, pos, AF_INET6);
}
static int ping_v6_seq_show(struct seq_file *seq, void *v)
{
if (v == SEQ_START_TOKEN) {
seq_puts(seq, IPV6_SEQ_DGRAM_HEADER);
} else {
int bucket = ((struct ping_iter_state *) seq->private)->bucket;
struct inet_sock *inet = inet_sk(v);
__u16 srcp = ntohs(inet->inet_sport);
__u16 destp = ntohs(inet->inet_dport);
ip6_dgram_sock_seq_show(seq, v, srcp, destp, bucket);
}
return 0;
}
static const struct seq_operations ping_v6_seq_ops = {
.start = ping_v6_seq_start,
.show = ping_v6_seq_show,
.next = ping_seq_next,
.stop = ping_seq_stop,
};
static int __net_init ping_v6_proc_init_net(struct net *net)
{
if (!proc_create_net("icmp6", 0444, net->proc_net, &ping_v6_seq_ops,
sizeof(struct ping_iter_state)))
return -ENOMEM;
return 0;
}
static void __net_exit ping_v6_proc_exit_net(struct net *net)
{
remove_proc_entry("icmp6", net->proc_net);
}
static struct pernet_operations ping_v6_net_ops = {
.init = ping_v6_proc_init_net,
.exit = ping_v6_proc_exit_net,
};
#endif
int __init pingv6_init(void)
{
#ifdef CONFIG_PROC_FS
int ret = register_pernet_subsys(&ping_v6_net_ops);
if (ret)
return ret;
#endif
pingv6_ops.ipv6_recv_error = ipv6_recv_error;
pingv6_ops.ip6_datagram_recv_common_ctl = ip6_datagram_recv_common_ctl;
pingv6_ops.ip6_datagram_recv_specific_ctl =
ip6_datagram_recv_specific_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_common_ctl = dummy_ip6_datagram_recv_ctl;
pingv6_ops.ip6_datagram_recv_specific_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;
#ifdef CONFIG_PROC_FS
unregister_pernet_subsys(&ping_v6_net_ops);
#endif
inet6_unregister_protosw(&pingv6_protosw);
}