1203 lines
28 KiB
C
1203 lines
28 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* INET An implementation of the TCP/IP protocol suite for the LINUX
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* operating system. INET is implemented using the BSD Socket
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* interface as the means of communication with the user level.
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*
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* "Ping" sockets
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*
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* Based on ipv4/udp.c code.
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*
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* Authors: Vasiliy Kulikov / Openwall (for Linux 2.6),
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* Pavel Kankovsky (for Linux 2.4.32)
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*
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* Pavel gave all rights to bugs to Vasiliy,
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* none of the bugs are Pavel's now.
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*/
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#include <linux/uaccess.h>
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#include <linux/types.h>
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#include <linux/fcntl.h>
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#include <linux/socket.h>
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#include <linux/sockios.h>
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#include <linux/in.h>
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#include <linux/errno.h>
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#include <linux/timer.h>
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#include <linux/mm.h>
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#include <linux/inet.h>
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#include <linux/netdevice.h>
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#include <net/snmp.h>
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#include <net/ip.h>
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#include <net/icmp.h>
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#include <net/protocol.h>
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#include <linux/skbuff.h>
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#include <linux/proc_fs.h>
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#include <linux/export.h>
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#include <net/sock.h>
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#include <net/ping.h>
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#include <net/udp.h>
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#include <net/route.h>
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#include <net/inet_common.h>
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#include <net/checksum.h>
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#if IS_ENABLED(CONFIG_IPV6)
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#include <linux/in6.h>
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#include <linux/icmpv6.h>
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#include <net/addrconf.h>
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#include <net/ipv6.h>
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#include <net/transp_v6.h>
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#endif
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struct ping_table {
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struct hlist_nulls_head hash[PING_HTABLE_SIZE];
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spinlock_t lock;
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};
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static struct ping_table ping_table;
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struct pingv6_ops pingv6_ops;
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EXPORT_SYMBOL_GPL(pingv6_ops);
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static u16 ping_port_rover;
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static inline u32 ping_hashfn(const struct net *net, u32 num, u32 mask)
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{
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u32 res = (num + net_hash_mix(net)) & mask;
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pr_debug("hash(%u) = %u\n", num, res);
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return res;
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}
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EXPORT_SYMBOL_GPL(ping_hash);
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static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
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struct net *net, unsigned int num)
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{
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return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
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}
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int ping_get_port(struct sock *sk, unsigned short ident)
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{
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struct hlist_nulls_node *node;
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struct hlist_nulls_head *hlist;
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struct inet_sock *isk, *isk2;
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struct sock *sk2 = NULL;
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isk = inet_sk(sk);
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spin_lock(&ping_table.lock);
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if (ident == 0) {
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u32 i;
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u16 result = ping_port_rover + 1;
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for (i = 0; i < (1L << 16); i++, result++) {
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if (!result)
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result++; /* avoid zero */
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hlist = ping_hashslot(&ping_table, sock_net(sk),
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result);
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ping_portaddr_for_each_entry(sk2, node, hlist) {
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isk2 = inet_sk(sk2);
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if (isk2->inet_num == result)
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goto next_port;
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}
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/* found */
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ping_port_rover = ident = result;
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break;
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next_port:
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;
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}
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if (i >= (1L << 16))
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goto fail;
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} else {
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hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
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ping_portaddr_for_each_entry(sk2, node, hlist) {
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isk2 = inet_sk(sk2);
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/* BUG? Why is this reuse and not reuseaddr? ping.c
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* doesn't turn off SO_REUSEADDR, and it doesn't expect
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* that other ping processes can steal its packets.
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*/
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if ((isk2->inet_num == ident) &&
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(sk2 != sk) &&
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(!sk2->sk_reuse || !sk->sk_reuse))
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goto fail;
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}
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}
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pr_debug("found port/ident = %d\n", ident);
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isk->inet_num = ident;
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if (sk_unhashed(sk)) {
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pr_debug("was not hashed\n");
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sock_hold(sk);
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sock_set_flag(sk, SOCK_RCU_FREE);
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hlist_nulls_add_head_rcu(&sk->sk_nulls_node, hlist);
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sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
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}
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spin_unlock(&ping_table.lock);
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return 0;
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fail:
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spin_unlock(&ping_table.lock);
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return 1;
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}
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EXPORT_SYMBOL_GPL(ping_get_port);
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int ping_hash(struct sock *sk)
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{
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pr_debug("ping_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
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BUG(); /* "Please do not press this button again." */
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return 0;
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}
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void ping_unhash(struct sock *sk)
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{
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struct inet_sock *isk = inet_sk(sk);
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pr_debug("ping_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
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spin_lock(&ping_table.lock);
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if (sk_hashed(sk)) {
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hlist_nulls_del_init_rcu(&sk->sk_nulls_node);
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sock_put(sk);
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isk->inet_num = 0;
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isk->inet_sport = 0;
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sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
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}
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spin_unlock(&ping_table.lock);
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}
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EXPORT_SYMBOL_GPL(ping_unhash);
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/* Called under rcu_read_lock() */
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static struct sock *ping_lookup(struct net *net, struct sk_buff *skb, u16 ident)
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{
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struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
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struct sock *sk = NULL;
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struct inet_sock *isk;
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struct hlist_nulls_node *hnode;
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int dif, sdif;
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if (skb->protocol == htons(ETH_P_IP)) {
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dif = inet_iif(skb);
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sdif = inet_sdif(skb);
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pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
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(int)ident, &ip_hdr(skb)->daddr, dif);
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#if IS_ENABLED(CONFIG_IPV6)
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} else if (skb->protocol == htons(ETH_P_IPV6)) {
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dif = inet6_iif(skb);
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sdif = inet6_sdif(skb);
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pr_debug("try to find: num = %d, daddr = %pI6c, dif = %d\n",
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(int)ident, &ipv6_hdr(skb)->daddr, dif);
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#endif
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} else {
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return NULL;
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}
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ping_portaddr_for_each_entry(sk, hnode, hslot) {
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isk = inet_sk(sk);
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pr_debug("iterate\n");
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if (isk->inet_num != ident)
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continue;
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if (skb->protocol == htons(ETH_P_IP) &&
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sk->sk_family == AF_INET) {
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pr_debug("found: %p: num=%d, daddr=%pI4, dif=%d\n", sk,
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(int) isk->inet_num, &isk->inet_rcv_saddr,
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sk->sk_bound_dev_if);
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if (isk->inet_rcv_saddr &&
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isk->inet_rcv_saddr != ip_hdr(skb)->daddr)
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continue;
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#if IS_ENABLED(CONFIG_IPV6)
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} else if (skb->protocol == htons(ETH_P_IPV6) &&
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sk->sk_family == AF_INET6) {
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pr_debug("found: %p: num=%d, daddr=%pI6c, dif=%d\n", sk,
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(int) isk->inet_num,
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&sk->sk_v6_rcv_saddr,
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sk->sk_bound_dev_if);
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if (!ipv6_addr_any(&sk->sk_v6_rcv_saddr) &&
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!ipv6_addr_equal(&sk->sk_v6_rcv_saddr,
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&ipv6_hdr(skb)->daddr))
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continue;
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#endif
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} else {
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continue;
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}
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if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif &&
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sk->sk_bound_dev_if != sdif)
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continue;
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goto exit;
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}
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sk = NULL;
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exit:
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return sk;
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}
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static void inet_get_ping_group_range_net(struct net *net, kgid_t *low,
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kgid_t *high)
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{
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kgid_t *data = net->ipv4.ping_group_range.range;
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unsigned int seq;
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do {
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seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
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*low = data[0];
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*high = data[1];
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} while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
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}
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int ping_init_sock(struct sock *sk)
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{
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struct net *net = sock_net(sk);
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kgid_t group = current_egid();
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struct group_info *group_info;
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int i;
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kgid_t low, high;
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int ret = 0;
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if (sk->sk_family == AF_INET6)
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sk->sk_ipv6only = 1;
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inet_get_ping_group_range_net(net, &low, &high);
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if (gid_lte(low, group) && gid_lte(group, high))
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return 0;
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group_info = get_current_groups();
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for (i = 0; i < group_info->ngroups; i++) {
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kgid_t gid = group_info->gid[i];
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if (gid_lte(low, gid) && gid_lte(gid, high))
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goto out_release_group;
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}
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ret = -EACCES;
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out_release_group:
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put_group_info(group_info);
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return ret;
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}
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EXPORT_SYMBOL_GPL(ping_init_sock);
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void ping_close(struct sock *sk, long timeout)
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{
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pr_debug("ping_close(sk=%p,sk->num=%u)\n",
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inet_sk(sk), inet_sk(sk)->inet_num);
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pr_debug("isk->refcnt = %d\n", refcount_read(&sk->sk_refcnt));
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sk_common_release(sk);
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}
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EXPORT_SYMBOL_GPL(ping_close);
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/* Checks the bind address and possibly modifies sk->sk_bound_dev_if. */
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static int ping_check_bind_addr(struct sock *sk, struct inet_sock *isk,
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struct sockaddr *uaddr, int addr_len)
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{
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struct net *net = sock_net(sk);
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if (sk->sk_family == AF_INET) {
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struct sockaddr_in *addr = (struct sockaddr_in *) uaddr;
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u32 tb_id = RT_TABLE_LOCAL;
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int chk_addr_ret;
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if (addr_len < sizeof(*addr))
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return -EINVAL;
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if (addr->sin_family != AF_INET &&
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!(addr->sin_family == AF_UNSPEC &&
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addr->sin_addr.s_addr == htonl(INADDR_ANY)))
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return -EAFNOSUPPORT;
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pr_debug("ping_check_bind_addr(sk=%p,addr=%pI4,port=%d)\n",
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sk, &addr->sin_addr.s_addr, ntohs(addr->sin_port));
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if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
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return 0;
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tb_id = l3mdev_fib_table_by_index(net, sk->sk_bound_dev_if) ? : tb_id;
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chk_addr_ret = inet_addr_type_table(net, addr->sin_addr.s_addr, tb_id);
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if (chk_addr_ret == RTN_MULTICAST ||
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chk_addr_ret == RTN_BROADCAST ||
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(chk_addr_ret != RTN_LOCAL &&
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!inet_can_nonlocal_bind(net, isk)))
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return -EADDRNOTAVAIL;
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#if IS_ENABLED(CONFIG_IPV6)
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} else if (sk->sk_family == AF_INET6) {
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struct sockaddr_in6 *addr = (struct sockaddr_in6 *) uaddr;
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int addr_type, scoped, has_addr;
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struct net_device *dev = NULL;
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if (addr_len < sizeof(*addr))
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return -EINVAL;
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if (addr->sin6_family != AF_INET6)
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return -EAFNOSUPPORT;
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pr_debug("ping_check_bind_addr(sk=%p,addr=%pI6c,port=%d)\n",
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sk, addr->sin6_addr.s6_addr, ntohs(addr->sin6_port));
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addr_type = ipv6_addr_type(&addr->sin6_addr);
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scoped = __ipv6_addr_needs_scope_id(addr_type);
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if ((addr_type != IPV6_ADDR_ANY &&
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!(addr_type & IPV6_ADDR_UNICAST)) ||
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(scoped && !addr->sin6_scope_id))
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return -EINVAL;
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rcu_read_lock();
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if (addr->sin6_scope_id) {
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dev = dev_get_by_index_rcu(net, addr->sin6_scope_id);
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if (!dev) {
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rcu_read_unlock();
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return -ENODEV;
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}
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}
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if (!dev && sk->sk_bound_dev_if) {
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dev = dev_get_by_index_rcu(net, sk->sk_bound_dev_if);
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if (!dev) {
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rcu_read_unlock();
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return -ENODEV;
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}
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}
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has_addr = pingv6_ops.ipv6_chk_addr(net, &addr->sin6_addr, dev,
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scoped);
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rcu_read_unlock();
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if (!(ipv6_can_nonlocal_bind(net, isk) || has_addr ||
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addr_type == IPV6_ADDR_ANY))
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return -EADDRNOTAVAIL;
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if (scoped)
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sk->sk_bound_dev_if = addr->sin6_scope_id;
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#endif
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} else {
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return -EAFNOSUPPORT;
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}
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return 0;
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}
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static void ping_set_saddr(struct sock *sk, struct sockaddr *saddr)
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{
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if (saddr->sa_family == AF_INET) {
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struct inet_sock *isk = inet_sk(sk);
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struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
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isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
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#if IS_ENABLED(CONFIG_IPV6)
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} else if (saddr->sa_family == AF_INET6) {
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struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
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struct ipv6_pinfo *np = inet6_sk(sk);
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sk->sk_v6_rcv_saddr = np->saddr = addr->sin6_addr;
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#endif
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}
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}
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/*
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* We need our own bind because there are no privileged id's == local ports.
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* Moreover, we don't allow binding to multi- and broadcast addresses.
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*/
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int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
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{
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struct inet_sock *isk = inet_sk(sk);
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unsigned short snum;
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int err;
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int dif = sk->sk_bound_dev_if;
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err = ping_check_bind_addr(sk, isk, uaddr, addr_len);
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if (err)
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return err;
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lock_sock(sk);
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err = -EINVAL;
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if (isk->inet_num != 0)
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goto out;
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err = -EADDRINUSE;
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snum = ntohs(((struct sockaddr_in *)uaddr)->sin_port);
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if (ping_get_port(sk, snum) != 0) {
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/* Restore possibly modified sk->sk_bound_dev_if by ping_check_bind_addr(). */
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sk->sk_bound_dev_if = dif;
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goto out;
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}
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ping_set_saddr(sk, uaddr);
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pr_debug("after bind(): num = %hu, dif = %d\n",
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isk->inet_num,
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sk->sk_bound_dev_if);
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err = 0;
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if (sk->sk_family == AF_INET && isk->inet_rcv_saddr)
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sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
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#if IS_ENABLED(CONFIG_IPV6)
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if (sk->sk_family == AF_INET6 && !ipv6_addr_any(&sk->sk_v6_rcv_saddr))
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sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
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#endif
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if (snum)
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sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
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isk->inet_sport = htons(isk->inet_num);
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isk->inet_daddr = 0;
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isk->inet_dport = 0;
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#if IS_ENABLED(CONFIG_IPV6)
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if (sk->sk_family == AF_INET6)
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memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
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#endif
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sk_dst_reset(sk);
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out:
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release_sock(sk);
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pr_debug("ping_v4_bind -> %d\n", err);
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return err;
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}
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EXPORT_SYMBOL_GPL(ping_bind);
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|
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/*
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* Is this a supported type of ICMP message?
|
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*/
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static inline int ping_supported(int family, int type, int code)
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{
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return (family == AF_INET && type == ICMP_ECHO && code == 0) ||
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(family == AF_INET && type == ICMP_EXT_ECHO && code == 0) ||
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(family == AF_INET6 && type == ICMPV6_ECHO_REQUEST && code == 0) ||
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(family == AF_INET6 && type == ICMPV6_EXT_ECHO_REQUEST && code == 0);
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}
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|
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/*
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* This routine is called by the ICMP module when it gets some
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* sort of error condition.
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*/
|
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|
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void ping_err(struct sk_buff *skb, int offset, u32 info)
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{
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int family;
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struct icmphdr *icmph;
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struct inet_sock *inet_sock;
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int type;
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int code;
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struct net *net = dev_net(skb->dev);
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struct sock *sk;
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int harderr;
|
|
int err;
|
|
|
|
if (skb->protocol == htons(ETH_P_IP)) {
|
|
family = AF_INET;
|
|
type = icmp_hdr(skb)->type;
|
|
code = icmp_hdr(skb)->code;
|
|
icmph = (struct icmphdr *)(skb->data + offset);
|
|
} else if (skb->protocol == htons(ETH_P_IPV6)) {
|
|
family = AF_INET6;
|
|
type = icmp6_hdr(skb)->icmp6_type;
|
|
code = icmp6_hdr(skb)->icmp6_code;
|
|
icmph = (struct icmphdr *) (skb->data + offset);
|
|
} else {
|
|
BUG();
|
|
}
|
|
|
|
/* We assume the packet has already been checked by icmp_unreach */
|
|
|
|
if (!ping_supported(family, icmph->type, icmph->code))
|
|
return;
|
|
|
|
pr_debug("ping_err(proto=0x%x,type=%d,code=%d,id=%04x,seq=%04x)\n",
|
|
skb->protocol, type, code, ntohs(icmph->un.echo.id),
|
|
ntohs(icmph->un.echo.sequence));
|
|
|
|
sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
|
|
if (!sk) {
|
|
pr_debug("no socket, dropping\n");
|
|
return; /* No socket for error */
|
|
}
|
|
pr_debug("err on socket %p\n", sk);
|
|
|
|
err = 0;
|
|
harderr = 0;
|
|
inet_sock = inet_sk(sk);
|
|
|
|
if (skb->protocol == htons(ETH_P_IP)) {
|
|
switch (type) {
|
|
default:
|
|
case ICMP_TIME_EXCEEDED:
|
|
err = EHOSTUNREACH;
|
|
break;
|
|
case ICMP_SOURCE_QUENCH:
|
|
/* This is not a real error but ping wants to see it.
|
|
* Report it with some fake errno.
|
|
*/
|
|
err = EREMOTEIO;
|
|
break;
|
|
case ICMP_PARAMETERPROB:
|
|
err = EPROTO;
|
|
harderr = 1;
|
|
break;
|
|
case ICMP_DEST_UNREACH:
|
|
if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
|
|
ipv4_sk_update_pmtu(skb, sk, info);
|
|
if (inet_sock->pmtudisc != IP_PMTUDISC_DONT) {
|
|
err = EMSGSIZE;
|
|
harderr = 1;
|
|
break;
|
|
}
|
|
goto out;
|
|
}
|
|
err = EHOSTUNREACH;
|
|
if (code <= NR_ICMP_UNREACH) {
|
|
harderr = icmp_err_convert[code].fatal;
|
|
err = icmp_err_convert[code].errno;
|
|
}
|
|
break;
|
|
case ICMP_REDIRECT:
|
|
/* See ICMP_SOURCE_QUENCH */
|
|
ipv4_sk_redirect(skb, sk);
|
|
err = EREMOTEIO;
|
|
break;
|
|
}
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
} else if (skb->protocol == htons(ETH_P_IPV6)) {
|
|
harderr = pingv6_ops.icmpv6_err_convert(type, code, &err);
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* RFC1122: OK. Passes ICMP errors back to application, as per
|
|
* 4.1.3.3.
|
|
*/
|
|
if ((family == AF_INET && !inet_sock->recverr) ||
|
|
(family == AF_INET6 && !inet6_sk(sk)->recverr)) {
|
|
if (!harderr || sk->sk_state != TCP_ESTABLISHED)
|
|
goto out;
|
|
} else {
|
|
if (family == AF_INET) {
|
|
ip_icmp_error(sk, skb, err, 0 /* no remote port */,
|
|
info, (u8 *)icmph);
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
} else if (family == AF_INET6) {
|
|
pingv6_ops.ipv6_icmp_error(sk, skb, err, 0,
|
|
info, (u8 *)icmph);
|
|
#endif
|
|
}
|
|
}
|
|
sk->sk_err = err;
|
|
sk_error_report(sk);
|
|
out:
|
|
return;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ping_err);
|
|
|
|
/*
|
|
* Copy and checksum an ICMP Echo packet from user space into a buffer
|
|
* starting from the payload.
|
|
*/
|
|
|
|
int ping_getfrag(void *from, char *to,
|
|
int offset, int fraglen, int odd, struct sk_buff *skb)
|
|
{
|
|
struct pingfakehdr *pfh = from;
|
|
|
|
if (offset == 0) {
|
|
fraglen -= sizeof(struct icmphdr);
|
|
if (fraglen < 0)
|
|
BUG();
|
|
if (!csum_and_copy_from_iter_full(to + sizeof(struct icmphdr),
|
|
fraglen, &pfh->wcheck,
|
|
&pfh->msg->msg_iter))
|
|
return -EFAULT;
|
|
} else if (offset < sizeof(struct icmphdr)) {
|
|
BUG();
|
|
} else {
|
|
if (!csum_and_copy_from_iter_full(to, fraglen, &pfh->wcheck,
|
|
&pfh->msg->msg_iter))
|
|
return -EFAULT;
|
|
}
|
|
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
/* For IPv6, checksum each skb as we go along, as expected by
|
|
* icmpv6_push_pending_frames. For IPv4, accumulate the checksum in
|
|
* wcheck, it will be finalized in ping_v4_push_pending_frames.
|
|
*/
|
|
if (pfh->family == AF_INET6) {
|
|
skb->csum = pfh->wcheck;
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
pfh->wcheck = 0;
|
|
}
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ping_getfrag);
|
|
|
|
static int ping_v4_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
|
|
struct flowi4 *fl4)
|
|
{
|
|
struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
|
|
|
|
if (!skb)
|
|
return 0;
|
|
pfh->wcheck = csum_partial((char *)&pfh->icmph,
|
|
sizeof(struct icmphdr), pfh->wcheck);
|
|
pfh->icmph.checksum = csum_fold(pfh->wcheck);
|
|
memcpy(icmp_hdr(skb), &pfh->icmph, sizeof(struct icmphdr));
|
|
skb->ip_summed = CHECKSUM_NONE;
|
|
return ip_push_pending_frames(sk, fl4);
|
|
}
|
|
|
|
int ping_common_sendmsg(int family, struct msghdr *msg, size_t len,
|
|
void *user_icmph, size_t icmph_len)
|
|
{
|
|
u8 type, code;
|
|
|
|
if (len > 0xFFFF)
|
|
return -EMSGSIZE;
|
|
|
|
/* Must have at least a full ICMP header. */
|
|
if (len < icmph_len)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* Check the flags.
|
|
*/
|
|
|
|
/* Mirror BSD error message compatibility */
|
|
if (msg->msg_flags & MSG_OOB)
|
|
return -EOPNOTSUPP;
|
|
|
|
/*
|
|
* Fetch the ICMP header provided by the userland.
|
|
* iovec is modified! The ICMP header is consumed.
|
|
*/
|
|
if (memcpy_from_msg(user_icmph, msg, icmph_len))
|
|
return -EFAULT;
|
|
|
|
if (family == AF_INET) {
|
|
type = ((struct icmphdr *) user_icmph)->type;
|
|
code = ((struct icmphdr *) user_icmph)->code;
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
} else if (family == AF_INET6) {
|
|
type = ((struct icmp6hdr *) user_icmph)->icmp6_type;
|
|
code = ((struct icmp6hdr *) user_icmph)->icmp6_code;
|
|
#endif
|
|
} else {
|
|
BUG();
|
|
}
|
|
|
|
if (!ping_supported(family, type, code))
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ping_common_sendmsg);
|
|
|
|
static int ping_v4_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
|
|
{
|
|
struct net *net = sock_net(sk);
|
|
struct flowi4 fl4;
|
|
struct inet_sock *inet = inet_sk(sk);
|
|
struct ipcm_cookie ipc;
|
|
struct icmphdr user_icmph;
|
|
struct pingfakehdr pfh;
|
|
struct rtable *rt = NULL;
|
|
struct ip_options_data opt_copy;
|
|
int free = 0;
|
|
__be32 saddr, daddr, faddr;
|
|
u8 tos;
|
|
int err;
|
|
|
|
pr_debug("ping_v4_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
|
|
|
|
err = ping_common_sendmsg(AF_INET, msg, len, &user_icmph,
|
|
sizeof(user_icmph));
|
|
if (err)
|
|
return err;
|
|
|
|
/*
|
|
* Get and verify the address.
|
|
*/
|
|
|
|
if (msg->msg_name) {
|
|
DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
|
|
if (msg->msg_namelen < sizeof(*usin))
|
|
return -EINVAL;
|
|
if (usin->sin_family != AF_INET)
|
|
return -EAFNOSUPPORT;
|
|
daddr = usin->sin_addr.s_addr;
|
|
/* no remote port */
|
|
} else {
|
|
if (sk->sk_state != TCP_ESTABLISHED)
|
|
return -EDESTADDRREQ;
|
|
daddr = inet->inet_daddr;
|
|
/* no remote port */
|
|
}
|
|
|
|
ipcm_init_sk(&ipc, inet);
|
|
|
|
if (msg->msg_controllen) {
|
|
err = ip_cmsg_send(sk, msg, &ipc, false);
|
|
if (unlikely(err)) {
|
|
kfree(ipc.opt);
|
|
return err;
|
|
}
|
|
if (ipc.opt)
|
|
free = 1;
|
|
}
|
|
if (!ipc.opt) {
|
|
struct ip_options_rcu *inet_opt;
|
|
|
|
rcu_read_lock();
|
|
inet_opt = rcu_dereference(inet->inet_opt);
|
|
if (inet_opt) {
|
|
memcpy(&opt_copy, inet_opt,
|
|
sizeof(*inet_opt) + inet_opt->opt.optlen);
|
|
ipc.opt = &opt_copy.opt;
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
saddr = ipc.addr;
|
|
ipc.addr = faddr = daddr;
|
|
|
|
if (ipc.opt && ipc.opt->opt.srr) {
|
|
if (!daddr) {
|
|
err = -EINVAL;
|
|
goto out_free;
|
|
}
|
|
faddr = ipc.opt->opt.faddr;
|
|
}
|
|
tos = get_rttos(&ipc, inet);
|
|
if (sock_flag(sk, SOCK_LOCALROUTE) ||
|
|
(msg->msg_flags & MSG_DONTROUTE) ||
|
|
(ipc.opt && ipc.opt->opt.is_strictroute)) {
|
|
tos |= RTO_ONLINK;
|
|
}
|
|
|
|
if (ipv4_is_multicast(daddr)) {
|
|
if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif))
|
|
ipc.oif = inet->mc_index;
|
|
if (!saddr)
|
|
saddr = inet->mc_addr;
|
|
} else if (!ipc.oif)
|
|
ipc.oif = inet->uc_index;
|
|
|
|
flowi4_init_output(&fl4, ipc.oif, ipc.sockc.mark, tos,
|
|
RT_SCOPE_UNIVERSE, sk->sk_protocol,
|
|
inet_sk_flowi_flags(sk), faddr, saddr, 0, 0,
|
|
sk->sk_uid);
|
|
|
|
fl4.fl4_icmp_type = user_icmph.type;
|
|
fl4.fl4_icmp_code = user_icmph.code;
|
|
|
|
security_sk_classify_flow(sk, flowi4_to_flowi_common(&fl4));
|
|
rt = ip_route_output_flow(net, &fl4, sk);
|
|
if (IS_ERR(rt)) {
|
|
err = PTR_ERR(rt);
|
|
rt = NULL;
|
|
if (err == -ENETUNREACH)
|
|
IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
|
|
goto out;
|
|
}
|
|
|
|
err = -EACCES;
|
|
if ((rt->rt_flags & RTCF_BROADCAST) &&
|
|
!sock_flag(sk, SOCK_BROADCAST))
|
|
goto out;
|
|
|
|
if (msg->msg_flags & MSG_CONFIRM)
|
|
goto do_confirm;
|
|
back_from_confirm:
|
|
|
|
if (!ipc.addr)
|
|
ipc.addr = fl4.daddr;
|
|
|
|
lock_sock(sk);
|
|
|
|
pfh.icmph.type = user_icmph.type; /* already checked */
|
|
pfh.icmph.code = user_icmph.code; /* ditto */
|
|
pfh.icmph.checksum = 0;
|
|
pfh.icmph.un.echo.id = inet->inet_sport;
|
|
pfh.icmph.un.echo.sequence = user_icmph.un.echo.sequence;
|
|
pfh.msg = msg;
|
|
pfh.wcheck = 0;
|
|
pfh.family = AF_INET;
|
|
|
|
err = ip_append_data(sk, &fl4, ping_getfrag, &pfh, len,
|
|
0, &ipc, &rt, msg->msg_flags);
|
|
if (err)
|
|
ip_flush_pending_frames(sk);
|
|
else
|
|
err = ping_v4_push_pending_frames(sk, &pfh, &fl4);
|
|
release_sock(sk);
|
|
|
|
out:
|
|
ip_rt_put(rt);
|
|
out_free:
|
|
if (free)
|
|
kfree(ipc.opt);
|
|
if (!err) {
|
|
icmp_out_count(sock_net(sk), user_icmph.type);
|
|
return len;
|
|
}
|
|
return err;
|
|
|
|
do_confirm:
|
|
if (msg->msg_flags & MSG_PROBE)
|
|
dst_confirm_neigh(&rt->dst, &fl4.daddr);
|
|
if (!(msg->msg_flags & MSG_PROBE) || len)
|
|
goto back_from_confirm;
|
|
err = 0;
|
|
goto out;
|
|
}
|
|
|
|
int ping_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags,
|
|
int *addr_len)
|
|
{
|
|
struct inet_sock *isk = inet_sk(sk);
|
|
int family = sk->sk_family;
|
|
struct sk_buff *skb;
|
|
int copied, err;
|
|
|
|
pr_debug("ping_recvmsg(sk=%p,sk->num=%u)\n", isk, isk->inet_num);
|
|
|
|
err = -EOPNOTSUPP;
|
|
if (flags & MSG_OOB)
|
|
goto out;
|
|
|
|
if (flags & MSG_ERRQUEUE)
|
|
return inet_recv_error(sk, msg, len, addr_len);
|
|
|
|
skb = skb_recv_datagram(sk, flags, &err);
|
|
if (!skb)
|
|
goto out;
|
|
|
|
copied = skb->len;
|
|
if (copied > len) {
|
|
msg->msg_flags |= MSG_TRUNC;
|
|
copied = len;
|
|
}
|
|
|
|
/* Don't bother checking the checksum */
|
|
err = skb_copy_datagram_msg(skb, 0, msg, copied);
|
|
if (err)
|
|
goto done;
|
|
|
|
sock_recv_timestamp(msg, sk, skb);
|
|
|
|
/* Copy the address and add cmsg data. */
|
|
if (family == AF_INET) {
|
|
DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
|
|
|
|
if (sin) {
|
|
sin->sin_family = AF_INET;
|
|
sin->sin_port = 0 /* skb->h.uh->source */;
|
|
sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
|
|
memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
|
|
*addr_len = sizeof(*sin);
|
|
}
|
|
|
|
if (isk->cmsg_flags)
|
|
ip_cmsg_recv(msg, skb);
|
|
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
} else if (family == AF_INET6) {
|
|
struct ipv6_pinfo *np = inet6_sk(sk);
|
|
struct ipv6hdr *ip6 = ipv6_hdr(skb);
|
|
DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, msg->msg_name);
|
|
|
|
if (sin6) {
|
|
sin6->sin6_family = AF_INET6;
|
|
sin6->sin6_port = 0;
|
|
sin6->sin6_addr = ip6->saddr;
|
|
sin6->sin6_flowinfo = 0;
|
|
if (np->sndflow)
|
|
sin6->sin6_flowinfo = ip6_flowinfo(ip6);
|
|
sin6->sin6_scope_id =
|
|
ipv6_iface_scope_id(&sin6->sin6_addr,
|
|
inet6_iif(skb));
|
|
*addr_len = sizeof(*sin6);
|
|
}
|
|
|
|
if (inet6_sk(sk)->rxopt.all)
|
|
pingv6_ops.ip6_datagram_recv_common_ctl(sk, msg, skb);
|
|
if (skb->protocol == htons(ETH_P_IPV6) &&
|
|
inet6_sk(sk)->rxopt.all)
|
|
pingv6_ops.ip6_datagram_recv_specific_ctl(sk, msg, skb);
|
|
else if (skb->protocol == htons(ETH_P_IP) && isk->cmsg_flags)
|
|
ip_cmsg_recv(msg, skb);
|
|
#endif
|
|
} else {
|
|
BUG();
|
|
}
|
|
|
|
err = copied;
|
|
|
|
done:
|
|
skb_free_datagram(sk, skb);
|
|
out:
|
|
pr_debug("ping_recvmsg -> %d\n", err);
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ping_recvmsg);
|
|
|
|
static enum skb_drop_reason __ping_queue_rcv_skb(struct sock *sk,
|
|
struct sk_buff *skb)
|
|
{
|
|
enum skb_drop_reason reason;
|
|
|
|
pr_debug("ping_queue_rcv_skb(sk=%p,sk->num=%d,skb=%p)\n",
|
|
inet_sk(sk), inet_sk(sk)->inet_num, skb);
|
|
if (sock_queue_rcv_skb_reason(sk, skb, &reason) < 0) {
|
|
kfree_skb_reason(skb, reason);
|
|
pr_debug("ping_queue_rcv_skb -> failed\n");
|
|
return reason;
|
|
}
|
|
return SKB_NOT_DROPPED_YET;
|
|
}
|
|
|
|
int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
return __ping_queue_rcv_skb(sk, skb) ? -1 : 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ping_queue_rcv_skb);
|
|
|
|
|
|
/*
|
|
* All we need to do is get the socket.
|
|
*/
|
|
|
|
enum skb_drop_reason ping_rcv(struct sk_buff *skb)
|
|
{
|
|
enum skb_drop_reason reason = SKB_DROP_REASON_NO_SOCKET;
|
|
struct sock *sk;
|
|
struct net *net = dev_net(skb->dev);
|
|
struct icmphdr *icmph = icmp_hdr(skb);
|
|
|
|
/* We assume the packet has already been checked by icmp_rcv */
|
|
|
|
pr_debug("ping_rcv(skb=%p,id=%04x,seq=%04x)\n",
|
|
skb, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
|
|
|
|
/* Push ICMP header back */
|
|
skb_push(skb, skb->data - (u8 *)icmph);
|
|
|
|
sk = ping_lookup(net, skb, ntohs(icmph->un.echo.id));
|
|
if (sk) {
|
|
struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
|
|
|
|
pr_debug("rcv on socket %p\n", sk);
|
|
if (skb2)
|
|
reason = __ping_queue_rcv_skb(sk, skb2);
|
|
else
|
|
reason = SKB_DROP_REASON_NOMEM;
|
|
}
|
|
|
|
if (reason)
|
|
pr_debug("no socket, dropping\n");
|
|
|
|
return reason;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ping_rcv);
|
|
|
|
struct proto ping_prot = {
|
|
.name = "PING",
|
|
.owner = THIS_MODULE,
|
|
.init = ping_init_sock,
|
|
.close = ping_close,
|
|
.connect = ip4_datagram_connect,
|
|
.disconnect = __udp_disconnect,
|
|
.setsockopt = ip_setsockopt,
|
|
.getsockopt = ip_getsockopt,
|
|
.sendmsg = ping_v4_sendmsg,
|
|
.recvmsg = ping_recvmsg,
|
|
.bind = ping_bind,
|
|
.backlog_rcv = ping_queue_rcv_skb,
|
|
.release_cb = ip4_datagram_release_cb,
|
|
.hash = ping_hash,
|
|
.unhash = ping_unhash,
|
|
.get_port = ping_get_port,
|
|
.put_port = ping_unhash,
|
|
.obj_size = sizeof(struct inet_sock),
|
|
};
|
|
EXPORT_SYMBOL(ping_prot);
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
|
|
static struct sock *ping_get_first(struct seq_file *seq, int start)
|
|
{
|
|
struct sock *sk;
|
|
struct ping_iter_state *state = seq->private;
|
|
struct net *net = seq_file_net(seq);
|
|
|
|
for (state->bucket = start; state->bucket < PING_HTABLE_SIZE;
|
|
++state->bucket) {
|
|
struct hlist_nulls_node *node;
|
|
struct hlist_nulls_head *hslot;
|
|
|
|
hslot = &ping_table.hash[state->bucket];
|
|
|
|
if (hlist_nulls_empty(hslot))
|
|
continue;
|
|
|
|
sk_nulls_for_each(sk, node, hslot) {
|
|
if (net_eq(sock_net(sk), net) &&
|
|
sk->sk_family == state->family)
|
|
goto found;
|
|
}
|
|
}
|
|
sk = NULL;
|
|
found:
|
|
return sk;
|
|
}
|
|
|
|
static struct sock *ping_get_next(struct seq_file *seq, struct sock *sk)
|
|
{
|
|
struct ping_iter_state *state = seq->private;
|
|
struct net *net = seq_file_net(seq);
|
|
|
|
do {
|
|
sk = sk_nulls_next(sk);
|
|
} while (sk && (!net_eq(sock_net(sk), net)));
|
|
|
|
if (!sk)
|
|
return ping_get_first(seq, state->bucket + 1);
|
|
return sk;
|
|
}
|
|
|
|
static struct sock *ping_get_idx(struct seq_file *seq, loff_t pos)
|
|
{
|
|
struct sock *sk = ping_get_first(seq, 0);
|
|
|
|
if (sk)
|
|
while (pos && (sk = ping_get_next(seq, sk)) != NULL)
|
|
--pos;
|
|
return pos ? NULL : sk;
|
|
}
|
|
|
|
void *ping_seq_start(struct seq_file *seq, loff_t *pos, sa_family_t family)
|
|
__acquires(RCU)
|
|
{
|
|
struct ping_iter_state *state = seq->private;
|
|
state->bucket = 0;
|
|
state->family = family;
|
|
|
|
rcu_read_lock();
|
|
|
|
return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ping_seq_start);
|
|
|
|
static void *ping_v4_seq_start(struct seq_file *seq, loff_t *pos)
|
|
{
|
|
return ping_seq_start(seq, pos, AF_INET);
|
|
}
|
|
|
|
void *ping_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
{
|
|
struct sock *sk;
|
|
|
|
if (v == SEQ_START_TOKEN)
|
|
sk = ping_get_idx(seq, 0);
|
|
else
|
|
sk = ping_get_next(seq, v);
|
|
|
|
++*pos;
|
|
return sk;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ping_seq_next);
|
|
|
|
void ping_seq_stop(struct seq_file *seq, void *v)
|
|
__releases(RCU)
|
|
{
|
|
rcu_read_unlock();
|
|
}
|
|
EXPORT_SYMBOL_GPL(ping_seq_stop);
|
|
|
|
static void ping_v4_format_sock(struct sock *sp, struct seq_file *f,
|
|
int bucket)
|
|
{
|
|
struct inet_sock *inet = inet_sk(sp);
|
|
__be32 dest = inet->inet_daddr;
|
|
__be32 src = inet->inet_rcv_saddr;
|
|
__u16 destp = ntohs(inet->inet_dport);
|
|
__u16 srcp = ntohs(inet->inet_sport);
|
|
|
|
seq_printf(f, "%5d: %08X:%04X %08X:%04X"
|
|
" %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u",
|
|
bucket, src, srcp, dest, destp, sp->sk_state,
|
|
sk_wmem_alloc_get(sp),
|
|
sk_rmem_alloc_get(sp),
|
|
0, 0L, 0,
|
|
from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
|
|
0, sock_i_ino(sp),
|
|
refcount_read(&sp->sk_refcnt), sp,
|
|
atomic_read(&sp->sk_drops));
|
|
}
|
|
|
|
static int ping_v4_seq_show(struct seq_file *seq, void *v)
|
|
{
|
|
seq_setwidth(seq, 127);
|
|
if (v == SEQ_START_TOKEN)
|
|
seq_puts(seq, " sl local_address rem_address st tx_queue "
|
|
"rx_queue tr tm->when retrnsmt uid timeout "
|
|
"inode ref pointer drops");
|
|
else {
|
|
struct ping_iter_state *state = seq->private;
|
|
|
|
ping_v4_format_sock(v, seq, state->bucket);
|
|
}
|
|
seq_pad(seq, '\n');
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations ping_v4_seq_ops = {
|
|
.start = ping_v4_seq_start,
|
|
.show = ping_v4_seq_show,
|
|
.next = ping_seq_next,
|
|
.stop = ping_seq_stop,
|
|
};
|
|
|
|
static int __net_init ping_v4_proc_init_net(struct net *net)
|
|
{
|
|
if (!proc_create_net("icmp", 0444, net->proc_net, &ping_v4_seq_ops,
|
|
sizeof(struct ping_iter_state)))
|
|
return -ENOMEM;
|
|
return 0;
|
|
}
|
|
|
|
static void __net_exit ping_v4_proc_exit_net(struct net *net)
|
|
{
|
|
remove_proc_entry("icmp", net->proc_net);
|
|
}
|
|
|
|
static struct pernet_operations ping_v4_net_ops = {
|
|
.init = ping_v4_proc_init_net,
|
|
.exit = ping_v4_proc_exit_net,
|
|
};
|
|
|
|
int __init ping_proc_init(void)
|
|
{
|
|
return register_pernet_subsys(&ping_v4_net_ops);
|
|
}
|
|
|
|
void ping_proc_exit(void)
|
|
{
|
|
unregister_pernet_subsys(&ping_v4_net_ops);
|
|
}
|
|
|
|
#endif
|
|
|
|
void __init ping_init(void)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < PING_HTABLE_SIZE; i++)
|
|
INIT_HLIST_NULLS_HEAD(&ping_table.hash[i], i);
|
|
spin_lock_init(&ping_table.lock);
|
|
}
|