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|
/*
* 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/udp.c code.
*
* Authors: Vasiliy Kulikov / Openwall (for Linux 2.6),
* Pavel Kankovsky (for Linux 2.4.32)
*
* Pavel gave all rights to bugs to Vasiliy,
* none of the bugs are Pavel's now.
*
*/
#include <linux/uaccess.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <net/snmp.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/icmp.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <linux/proc_fs.h>
#include <linux/export.h>
#include <net/sock.h>
#include <net/ping.h>
#include <net/udp.h>
#include <net/route.h>
#include <net/inet_common.h>
#include <net/checksum.h>
static struct ping_table ping_table;
static u16 ping_port_rover;
static inline int ping_hashfn(struct net *net, unsigned num, unsigned mask)
{
int res = (num + net_hash_mix(net)) & mask;
pr_debug("hash(%d) = %d\n", num, res);
return res;
}
static inline struct hlist_nulls_head *ping_hashslot(struct ping_table *table,
struct net *net, unsigned num)
{
return &table->hash[ping_hashfn(net, num, PING_HTABLE_MASK)];
}
static int ping_v4_get_port(struct sock *sk, unsigned short ident)
{
struct hlist_nulls_node *node;
struct hlist_nulls_head *hlist;
struct inet_sock *isk, *isk2;
struct sock *sk2 = NULL;
isk = inet_sk(sk);
write_lock_bh(&ping_table.lock);
if (ident == 0) {
u32 i;
u16 result = ping_port_rover + 1;
for (i = 0; i < (1L << 16); i++, result++) {
if (!result)
result++; /* avoid zero */
hlist = ping_hashslot(&ping_table, sock_net(sk),
result);
ping_portaddr_for_each_entry(sk2, node, hlist) {
isk2 = inet_sk(sk2);
if (isk2->inet_num == result)
goto next_port;
}
/* found */
ping_port_rover = ident = result;
break;
next_port:
;
}
if (i >= (1L << 16))
goto fail;
} else {
hlist = ping_hashslot(&ping_table, sock_net(sk), ident);
ping_portaddr_for_each_entry(sk2, node, hlist) {
isk2 = inet_sk(sk2);
if ((isk2->inet_num == ident) &&
(sk2 != sk) &&
(!sk2->sk_reuse || !sk->sk_reuse))
goto fail;
}
}
pr_debug("found port/ident = %d\n", ident);
isk->inet_num = ident;
if (sk_unhashed(sk)) {
pr_debug("was not hashed\n");
sock_hold(sk);
hlist_nulls_add_head(&sk->sk_nulls_node, hlist);
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
}
write_unlock_bh(&ping_table.lock);
return 0;
fail:
write_unlock_bh(&ping_table.lock);
return 1;
}
static void ping_v4_hash(struct sock *sk)
{
pr_debug("ping_v4_hash(sk->port=%u)\n", inet_sk(sk)->inet_num);
BUG(); /* "Please do not press this button again." */
}
static void ping_v4_unhash(struct sock *sk)
{
struct inet_sock *isk = inet_sk(sk);
pr_debug("ping_v4_unhash(isk=%p,isk->num=%u)\n", isk, isk->inet_num);
if (sk_hashed(sk)) {
write_lock_bh(&ping_table.lock);
hlist_nulls_del(&sk->sk_nulls_node);
sock_put(sk);
isk->inet_num = 0;
isk->inet_sport = 0;
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
write_unlock_bh(&ping_table.lock);
}
}
static struct sock *ping_v4_lookup(struct net *net, __be32 saddr, __be32 daddr,
u16 ident, int dif)
{
struct hlist_nulls_head *hslot = ping_hashslot(&ping_table, net, ident);
struct sock *sk = NULL;
struct inet_sock *isk;
struct hlist_nulls_node *hnode;
pr_debug("try to find: num = %d, daddr = %pI4, dif = %d\n",
(int)ident, &daddr, dif);
read_lock_bh(&ping_table.lock);
ping_portaddr_for_each_entry(sk, hnode, hslot) {
isk = inet_sk(sk);
pr_debug("found: %p: num = %d, daddr = %pI4, dif = %d\n", sk,
(int)isk->inet_num, &isk->inet_rcv_saddr,
sk->sk_bound_dev_if);
pr_debug("iterate\n");
if (isk->inet_num != ident)
continue;
if (isk->inet_rcv_saddr && isk->inet_rcv_saddr != daddr)
continue;
if (sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)
continue;
sock_hold(sk);
goto exit;
}
sk = NULL;
exit:
read_unlock_bh(&ping_table.lock);
return sk;
}
static void inet_get_ping_group_range_net(struct net *net, gid_t *low,
gid_t *high)
{
gid_t *data = net->ipv4.sysctl_ping_group_range;
unsigned seq;
do {
seq = read_seqbegin(&sysctl_local_ports.lock);
*low = data[0];
*high = data[1];
} while (read_seqretry(&sysctl_local_ports.lock, seq));
}
static int ping_init_sock(struct sock *sk)
{
struct net *net = sock_net(sk);
gid_t group = current_egid();
gid_t range[2];
struct group_info *group_info = get_current_groups();
int i, j, count = group_info->ngroups;
kgid_t low, high;
inet_get_ping_group_range_net(net, range, range+1);
low = make_kgid(&init_user_ns, range[0]);
high = make_kgid(&init_user_ns, range[1]);
if (!gid_valid(low) || !gid_valid(high) || gid_lt(high, low))
return -EACCES;
if (range[0] <= group && group <= range[1])
return 0;
for (i = 0; i < group_info->nblocks; i++) {
int cp_count = min_t(int, NGROUPS_PER_BLOCK, count);
for (j = 0; j < cp_count; j++) {
kgid_t gid = group_info->blocks[i][j];
if (gid_lte(low, gid) && gid_lte(gid, high))
return 0;
}
count -= cp_count;
}
return -EACCES;
}
static void ping_close(struct sock *sk, long timeout)
{
pr_debug("ping_close(sk=%p,sk->num=%u)\n",
inet_sk(sk), inet_sk(sk)->inet_num);
pr_debug("isk->refcnt = %d\n", sk->sk_refcnt.counter);
sk_common_release(sk);
}
/*
* We need our own bind because there are no privileged id's == local ports.
* Moreover, we don't allow binding to multi- and broadcast addresses.
*/
static int ping_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
struct sockaddr_in *addr = (struct sockaddr_in *)uaddr;
struct inet_sock *isk = inet_sk(sk);
unsigned short snum;
int chk_addr_ret;
int err;
if (addr_len < sizeof(struct sockaddr_in))
return -EINVAL;
pr_debug("ping_v4_bind(sk=%p,sa_addr=%08x,sa_port=%d)\n",
sk, addr->sin_addr.s_addr, ntohs(addr->sin_port));
chk_addr_ret = inet_addr_type(sock_net(sk), addr->sin_addr.s_addr);
if (addr->sin_addr.s_addr == htonl(INADDR_ANY))
chk_addr_ret = RTN_LOCAL;
if ((sysctl_ip_nonlocal_bind == 0 &&
isk->freebind == 0 && isk->transparent == 0 &&
chk_addr_ret != RTN_LOCAL) ||
chk_addr_ret == RTN_MULTICAST ||
chk_addr_ret == RTN_BROADCAST)
return -EADDRNOTAVAIL;
lock_sock(sk);
err = -EINVAL;
if (isk->inet_num != 0)
goto out;
err = -EADDRINUSE;
isk->inet_rcv_saddr = isk->inet_saddr = addr->sin_addr.s_addr;
snum = ntohs(addr->sin_port);
if (ping_v4_get_port(sk, snum) != 0) {
isk->inet_saddr = isk->inet_rcv_saddr = 0;
goto out;
}
pr_debug("after bind(): num = %d, daddr = %pI4, dif = %d\n",
(int)isk->inet_num,
&isk->inet_rcv_saddr,
(int)sk->sk_bound_dev_if);
err = 0;
if (isk->inet_rcv_saddr)
sk->sk_userlocks |= SOCK_BINDADDR_LOCK;
if (snum)
sk->sk_userlocks |= SOCK_BINDPORT_LOCK;
isk->inet_sport = htons(isk->inet_num);
isk->inet_daddr = 0;
isk->inet_dport = 0;
sk_dst_reset(sk);
out:
release_sock(sk);
pr_debug("ping_v4_bind -> %d\n", err);
return err;
}
/*
* Is this a supported type of ICMP message?
*/
static inline int ping_supported(int type, int code)
{
if (type == ICMP_ECHO && code == 0)
return 1;
return 0;
}
/*
* This routine is called by the ICMP module when it gets some
* sort of error condition.
*/
static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb);
void ping_err(struct sk_buff *skb, u32 info)
{
struct iphdr *iph = (struct iphdr *)skb->data;
struct icmphdr *icmph = (struct icmphdr *)(skb->data+(iph->ihl<<2));
struct inet_sock *inet_sock;
int type = icmph->type;
int code = icmph->code;
struct net *net = dev_net(skb->dev);
struct sock *sk;
int harderr;
int err;
/* We assume the packet has already been checked by icmp_unreach */
if (!ping_supported(icmph->type, icmph->code))
return;
pr_debug("ping_err(type=%04x,code=%04x,id=%04x,seq=%04x)\n", type,
code, ntohs(icmph->un.echo.id), ntohs(icmph->un.echo.sequence));
sk = ping_v4_lookup(net, iph->daddr, iph->saddr,
ntohs(icmph->un.echo.id), skb->dev->ifindex);
if (sk == NULL) {
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);
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 */
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 */
err = EREMOTEIO;
break;
}
/*
* RFC1122: OK. Passes ICMP errors back to application, as per
* 4.1.3.3.
*/
if (!inet_sock->recverr) {
if (!harderr || sk->sk_state != TCP_ESTABLISHED)
goto out;
} else {
ip_icmp_error(sk, skb, err, 0 /* no remote port */,
info, (u8 *)icmph);
}
sk->sk_err = err;
sk->sk_error_report(sk);
out:
sock_put(sk);
}
/*
* Copy and checksum an ICMP Echo packet from user space into a buffer.
*/
struct pingfakehdr {
struct icmphdr icmph;
struct iovec *iov;
__wsum wcheck;
};
static int ping_getfrag(void *from, char * to,
int offset, int fraglen, int odd, struct sk_buff *skb)
{
struct pingfakehdr *pfh = (struct pingfakehdr *)from;
if (offset == 0) {
if (fraglen < sizeof(struct icmphdr))
BUG();
if (csum_partial_copy_fromiovecend(to + sizeof(struct icmphdr),
pfh->iov, 0, fraglen - sizeof(struct icmphdr),
&pfh->wcheck))
return -EFAULT;
return 0;
}
if (offset < sizeof(struct icmphdr))
BUG();
if (csum_partial_copy_fromiovecend
(to, pfh->iov, offset - sizeof(struct icmphdr),
fraglen, &pfh->wcheck))
return -EFAULT;
return 0;
}
static int ping_push_pending_frames(struct sock *sk, struct pingfakehdr *pfh,
struct flowi4 *fl4)
{
struct sk_buff *skb = skb_peek(&sk->sk_write_queue);
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);
}
static int ping_sendmsg(struct kiocb *iocb, 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_sendmsg(sk=%p,sk->num=%u)\n", inet, inet->inet_num);
if (len > 0xFFFF)
return -EMSGSIZE;
/*
* 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!
*/
if (memcpy_fromiovec((u8 *)&user_icmph, msg->msg_iov,
sizeof(struct icmphdr)))
return -EFAULT;
if (!ping_supported(user_icmph.type, user_icmph.code))
return -EINVAL;
/*
* Get and verify the address.
*/
if (msg->msg_name) {
struct sockaddr_in *usin = (struct sockaddr_in *)msg->msg_name;
if (msg->msg_namelen < sizeof(*usin))
return -EINVAL;
if (usin->sin_family != AF_INET)
return -EINVAL;
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 */
}
ipc.addr = inet->inet_saddr;
ipc.opt = NULL;
ipc.oif = sk->sk_bound_dev_if;
ipc.tx_flags = 0;
err = sock_tx_timestamp(sk, &ipc.tx_flags);
if (err)
return err;
if (msg->msg_controllen) {
err = ip_cmsg_send(sock_net(sk), msg, &ipc);
if (err)
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)
return -EINVAL;
faddr = ipc.opt->opt.faddr;
}
tos = RT_TOS(inet->tos);
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)
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, sk->sk_mark, tos,
RT_SCOPE_UNIVERSE, sk->sk_protocol,
inet_sk_flowi_flags(sk), faddr, saddr, 0, 0);
security_sk_classify_flow(sk, flowi4_to_flowi(&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_BH(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.iov = msg->msg_iov;
pfh.wcheck = 0;
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_push_pending_frames(sk, &pfh, &fl4);
release_sock(sk);
out:
ip_rt_put(rt);
if (free)
kfree(ipc.opt);
if (!err) {
icmp_out_count(sock_net(sk), user_icmph.type);
return len;
}
return err;
do_confirm:
dst_confirm(&rt->dst);
if (!(msg->msg_flags & MSG_PROBE) || len)
goto back_from_confirm;
err = 0;
goto out;
}
static int ping_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
size_t len, int noblock, int flags, int *addr_len)
{
struct inet_sock *isk = inet_sk(sk);
struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name;
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 (addr_len)
*addr_len = sizeof(*sin);
if (flags & MSG_ERRQUEUE)
return ip_recv_error(sk, msg, len);
skb = skb_recv_datagram(sk, flags, noblock, &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_iovec(skb, 0, msg->msg_iov, copied);
if (err)
goto done;
sock_recv_timestamp(msg, sk, skb);
/* Copy the address. */
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));
}
if (isk->cmsg_flags)
ip_cmsg_recv(msg, skb);
err = copied;
done:
skb_free_datagram(sk, skb);
out:
pr_debug("ping_recvmsg -> %d\n", err);
return err;
}
static int ping_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
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(sk, skb) < 0) {
kfree_skb(skb);
pr_debug("ping_queue_rcv_skb -> failed\n");
return -1;
}
return 0;
}
/*
* All we need to do is get the socket.
*/
void ping_rcv(struct sk_buff *skb)
{
struct sock *sk;
struct net *net = dev_net(skb->dev);
struct iphdr *iph = ip_hdr(skb);
struct icmphdr *icmph = icmp_hdr(skb);
__be32 saddr = iph->saddr;
__be32 daddr = iph->daddr;
/* 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_v4_lookup(net, saddr, daddr, ntohs(icmph->un.echo.id),
skb->dev->ifindex);
if (sk != NULL) {
pr_debug("rcv on socket %p\n", sk);
ping_queue_rcv_skb(sk, skb_get(skb));
sock_put(sk);
return;
}
pr_debug("no socket, dropping\n");
/* We're called from icmp_rcv(). kfree_skb() is done there. */
}
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_sendmsg,
.recvmsg = ping_recvmsg,
.bind = ping_bind,
.backlog_rcv = ping_queue_rcv_skb,
.hash = ping_v4_hash,
.unhash = ping_v4_unhash,
.get_port = ping_v4_get_port,
.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))
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;
}
static void *ping_seq_start(struct seq_file *seq, loff_t *pos)
{
struct ping_iter_state *state = seq->private;
state->bucket = 0;
read_lock_bh(&ping_table.lock);
return *pos ? ping_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
}
static 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;
}
static void ping_seq_stop(struct seq_file *seq, void *v)
{
read_unlock_bh(&ping_table.lock);
}
static void ping_format_sock(struct sock *sp, struct seq_file *f,
int bucket, int *len)
{
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 %5d %8d %lu %d %pK %d%n",
bucket, src, srcp, dest, destp, sp->sk_state,
sk_wmem_alloc_get(sp),
sk_rmem_alloc_get(sp),
0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp),
atomic_read(&sp->sk_refcnt), sp,
atomic_read(&sp->sk_drops), len);
}
static int ping_seq_show(struct seq_file *seq, void *v)
{
if (v == SEQ_START_TOKEN)
seq_printf(seq, "%-127s\n",
" 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;
int len;
ping_format_sock(v, seq, state->bucket, &len);
seq_printf(seq, "%*s\n", 127 - len, "");
}
return 0;
}
static const struct seq_operations ping_seq_ops = {
.show = ping_seq_show,
.start = ping_seq_start,
.next = ping_seq_next,
.stop = ping_seq_stop,
};
static int ping_seq_open(struct inode *inode, struct file *file)
{
return seq_open_net(inode, file, &ping_seq_ops,
sizeof(struct ping_iter_state));
}
static const struct file_operations ping_seq_fops = {
.open = ping_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release_net,
};
static int ping_proc_register(struct net *net)
{
struct proc_dir_entry *p;
int rc = 0;
p = proc_net_fops_create(net, "icmp", S_IRUGO, &ping_seq_fops);
if (!p)
rc = -ENOMEM;
return rc;
}
static void ping_proc_unregister(struct net *net)
{
proc_net_remove(net, "icmp");
}
static int __net_init ping_proc_init_net(struct net *net)
{
return ping_proc_register(net);
}
static void __net_exit ping_proc_exit_net(struct net *net)
{
ping_proc_unregister(net);
}
static struct pernet_operations ping_net_ops = {
.init = ping_proc_init_net,
.exit = ping_proc_exit_net,
};
int __init ping_proc_init(void)
{
return register_pernet_subsys(&ping_net_ops);
}
void ping_proc_exit(void)
{
unregister_pernet_subsys(&ping_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);
rwlock_init(&ping_table.lock);
}
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