diff options
Diffstat (limited to 'net/ipv4/ping.c')
| -rw-r--r-- | net/ipv4/ping.c | 935 | 
1 files changed, 935 insertions, 0 deletions
diff --git a/net/ipv4/ping.c b/net/ipv4/ping.c new file mode 100644 index 00000000000..1f3bb11490c --- /dev/null +++ b/net/ipv4/ping.c @@ -0,0 +1,935 @@ +/* + * 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 <asm/system.h> +#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 <net/sock.h> +#include <net/ping.h> +#include <net/icmp.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)) { +		struct hlist_nulls_head *hslot; + +		hslot = ping_hashslot(&ping_table, sock_net(sk), isk->inet_num); +		write_lock_bh(&ping_table.lock); +		hlist_nulls_del(&sk->sk_nulls_node); +		sock_put(sk); +		isk->inet_num = 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, u32 saddr, u32 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 = %ld, dif = %d\n", +			 (int)ident, (unsigned long)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 = %ld, dif = %d\n", sk, +			 (int)isk->inet_num, (unsigned long)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; + +	inet_get_ping_group_range_net(net, range, range+1); +	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++) { +			group = group_info->blocks[i][j]; +			if (range[0] <= group && group <= range[1]) +				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 == 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 = %ld, dif = %d\n", +		(int)isk->inet_num, +		(unsigned long) 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) { +		ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS); +		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; +	u32 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; +	u32 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; +	} + +	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); + +	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) { +		ICMP_INC_STATS_BH(sock_net(sk), ICMP_MIB_INERRORS); +		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); +	u32 saddr = iph->saddr; +	u32 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); +}  |