1 files changed, 802 insertions, 0 deletions

diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c
new file mode 100644
index 00000000000..313c1408da3
--- /dev/null
+++ b/net/ipv4/tcp_diag.c
@@ -0,0 +1,802 @@
+/*
+ * tcp_diag.c	Module for monitoring TCP sockets.
+ *
+ * Version:	$Id: tcp_diag.c,v 1.3 2002/02/01 22:01:04 davem Exp $
+ *
+ * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ *	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.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/random.h>
+#include <linux/cache.h>
+#include <linux/init.h>
+#include <linux/time.h>
+
+#include <net/icmp.h>
+#include <net/tcp.h>
+#include <net/ipv6.h>
+#include <net/inet_common.h>
+
+#include <linux/inet.h>
+#include <linux/stddef.h>
+
+#include <linux/tcp_diag.h>
+
+struct tcpdiag_entry
+{
+	u32 *saddr;
+	u32 *daddr;
+	u16 sport;
+	u16 dport;
+	u16 family;
+	u16 userlocks;
+};
+
+static struct sock *tcpnl;
+
+
+#define TCPDIAG_PUT(skb, attrtype, attrlen) \
+({ int rtalen = RTA_LENGTH(attrlen);        \
+   struct rtattr *rta;                      \
+   if (skb_tailroom(skb) < RTA_ALIGN(rtalen)) goto nlmsg_failure; \
+   rta = (void*)__skb_put(skb, RTA_ALIGN(rtalen)); \
+   rta->rta_type = attrtype;                \
+   rta->rta_len = rtalen;                   \
+   RTA_DATA(rta); })
+
+static int tcpdiag_fill(struct sk_buff *skb, struct sock *sk,
+			int ext, u32 pid, u32 seq, u16 nlmsg_flags)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct tcpdiagmsg *r;
+	struct nlmsghdr  *nlh;
+	struct tcp_info  *info = NULL;
+	struct tcpdiag_meminfo  *minfo = NULL;
+	struct tcpvegas_info *vinfo = NULL;
+	unsigned char	 *b = skb->tail;
+
+	nlh = NLMSG_PUT(skb, pid, seq, TCPDIAG_GETSOCK, sizeof(*r));
+	nlh->nlmsg_flags = nlmsg_flags;
+	r = NLMSG_DATA(nlh);
+	if (sk->sk_state != TCP_TIME_WAIT) {
+		if (ext & (1<<(TCPDIAG_MEMINFO-1)))
+			minfo = TCPDIAG_PUT(skb, TCPDIAG_MEMINFO, sizeof(*minfo));
+		if (ext & (1<<(TCPDIAG_INFO-1)))
+			info = TCPDIAG_PUT(skb, TCPDIAG_INFO, sizeof(*info));
+		
+		if ((tcp_is_westwood(tp) || tcp_is_vegas(tp))
+		    && (ext & (1<<(TCPDIAG_VEGASINFO-1))))
+			vinfo = TCPDIAG_PUT(skb, TCPDIAG_VEGASINFO, sizeof(*vinfo));
+	}
+	r->tcpdiag_family = sk->sk_family;
+	r->tcpdiag_state = sk->sk_state;
+	r->tcpdiag_timer = 0;
+	r->tcpdiag_retrans = 0;
+
+	r->id.tcpdiag_if = sk->sk_bound_dev_if;
+	r->id.tcpdiag_cookie[0] = (u32)(unsigned long)sk;
+	r->id.tcpdiag_cookie[1] = (u32)(((unsigned long)sk >> 31) >> 1);
+
+	if (r->tcpdiag_state == TCP_TIME_WAIT) {
+		struct tcp_tw_bucket *tw = (struct tcp_tw_bucket*)sk;
+		long tmo = tw->tw_ttd - jiffies;
+		if (tmo < 0)
+			tmo = 0;
+
+		r->id.tcpdiag_sport = tw->tw_sport;
+		r->id.tcpdiag_dport = tw->tw_dport;
+		r->id.tcpdiag_src[0] = tw->tw_rcv_saddr;
+		r->id.tcpdiag_dst[0] = tw->tw_daddr;
+		r->tcpdiag_state = tw->tw_substate;
+		r->tcpdiag_timer = 3;
+		r->tcpdiag_expires = (tmo*1000+HZ-1)/HZ;
+		r->tcpdiag_rqueue = 0;
+		r->tcpdiag_wqueue = 0;
+		r->tcpdiag_uid = 0;
+		r->tcpdiag_inode = 0;
+#ifdef CONFIG_IP_TCPDIAG_IPV6
+		if (r->tcpdiag_family == AF_INET6) {
+			ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_src,
+				       &tw->tw_v6_rcv_saddr);
+			ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_dst,
+				       &tw->tw_v6_daddr);
+		}
+#endif
+		nlh->nlmsg_len = skb->tail - b;
+		return skb->len;
+	}
+
+	r->id.tcpdiag_sport = inet->sport;
+	r->id.tcpdiag_dport = inet->dport;
+	r->id.tcpdiag_src[0] = inet->rcv_saddr;
+	r->id.tcpdiag_dst[0] = inet->daddr;
+
+#ifdef CONFIG_IP_TCPDIAG_IPV6
+	if (r->tcpdiag_family == AF_INET6) {
+		struct ipv6_pinfo *np = inet6_sk(sk);
+
+		ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_src,
+			       &np->rcv_saddr);
+		ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_dst,
+			       &np->daddr);
+	}
+#endif
+
+#define EXPIRES_IN_MS(tmo)  ((tmo-jiffies)*1000+HZ-1)/HZ
+
+	if (tp->pending == TCP_TIME_RETRANS) {
+		r->tcpdiag_timer = 1;
+		r->tcpdiag_retrans = tp->retransmits;
+		r->tcpdiag_expires = EXPIRES_IN_MS(tp->timeout);
+	} else if (tp->pending == TCP_TIME_PROBE0) {
+		r->tcpdiag_timer = 4;
+		r->tcpdiag_retrans = tp->probes_out;
+		r->tcpdiag_expires = EXPIRES_IN_MS(tp->timeout);
+	} else if (timer_pending(&sk->sk_timer)) {
+		r->tcpdiag_timer = 2;
+		r->tcpdiag_retrans = tp->probes_out;
+		r->tcpdiag_expires = EXPIRES_IN_MS(sk->sk_timer.expires);
+	} else {
+		r->tcpdiag_timer = 0;
+		r->tcpdiag_expires = 0;
+	}
+#undef EXPIRES_IN_MS
+
+	r->tcpdiag_rqueue = tp->rcv_nxt - tp->copied_seq;
+	r->tcpdiag_wqueue = tp->write_seq - tp->snd_una;
+	r->tcpdiag_uid = sock_i_uid(sk);
+	r->tcpdiag_inode = sock_i_ino(sk);
+
+	if (minfo) {
+		minfo->tcpdiag_rmem = atomic_read(&sk->sk_rmem_alloc);
+		minfo->tcpdiag_wmem = sk->sk_wmem_queued;
+		minfo->tcpdiag_fmem = sk->sk_forward_alloc;
+		minfo->tcpdiag_tmem = atomic_read(&sk->sk_wmem_alloc);
+	}
+
+	if (info) 
+		tcp_get_info(sk, info);
+
+	if (vinfo) {
+		if (tcp_is_vegas(tp)) {
+			vinfo->tcpv_enabled = tp->vegas.doing_vegas_now;
+			vinfo->tcpv_rttcnt = tp->vegas.cntRTT;
+			vinfo->tcpv_rtt = jiffies_to_usecs(tp->vegas.baseRTT);
+			vinfo->tcpv_minrtt = jiffies_to_usecs(tp->vegas.minRTT);
+		} else {
+			vinfo->tcpv_enabled = 0;
+			vinfo->tcpv_rttcnt = 0;
+			vinfo->tcpv_rtt = jiffies_to_usecs(tp->westwood.rtt);
+			vinfo->tcpv_minrtt = jiffies_to_usecs(tp->westwood.rtt_min);
+		}
+	}
+
+	nlh->nlmsg_len = skb->tail - b;
+	return skb->len;
+
+nlmsg_failure:
+	skb_trim(skb, b - skb->data);
+	return -1;
+}
+
+extern struct sock *tcp_v4_lookup(u32 saddr, u16 sport, u32 daddr, u16 dport,
+				  int dif);
+#ifdef CONFIG_IP_TCPDIAG_IPV6
+extern struct sock *tcp_v6_lookup(struct in6_addr *saddr, u16 sport,
+				  struct in6_addr *daddr, u16 dport,
+				  int dif);
+#else
+static inline struct sock *tcp_v6_lookup(struct in6_addr *saddr, u16 sport,
+					 struct in6_addr *daddr, u16 dport,
+					 int dif)
+{
+	return NULL;
+}
+#endif
+
+static int tcpdiag_get_exact(struct sk_buff *in_skb, const struct nlmsghdr *nlh)
+{
+	int err;
+	struct sock *sk;
+	struct tcpdiagreq *req = NLMSG_DATA(nlh);
+	struct sk_buff *rep;
+
+	if (req->tcpdiag_family == AF_INET) {
+		sk = tcp_v4_lookup(req->id.tcpdiag_dst[0], req->id.tcpdiag_dport,
+				   req->id.tcpdiag_src[0], req->id.tcpdiag_sport,
+				   req->id.tcpdiag_if);
+	}
+#ifdef CONFIG_IP_TCPDIAG_IPV6
+	else if (req->tcpdiag_family == AF_INET6) {
+		sk = tcp_v6_lookup((struct in6_addr*)req->id.tcpdiag_dst, req->id.tcpdiag_dport,
+				   (struct in6_addr*)req->id.tcpdiag_src, req->id.tcpdiag_sport,
+				   req->id.tcpdiag_if);
+	}
+#endif
+	else {
+		return -EINVAL;
+	}
+
+	if (sk == NULL)
+		return -ENOENT;
+
+	err = -ESTALE;
+	if ((req->id.tcpdiag_cookie[0] != TCPDIAG_NOCOOKIE ||
+	     req->id.tcpdiag_cookie[1] != TCPDIAG_NOCOOKIE) &&
+	    ((u32)(unsigned long)sk != req->id.tcpdiag_cookie[0] ||
+	     (u32)((((unsigned long)sk) >> 31) >> 1) != req->id.tcpdiag_cookie[1]))
+		goto out;
+
+	err = -ENOMEM;
+	rep = alloc_skb(NLMSG_SPACE(sizeof(struct tcpdiagmsg)+
+				    sizeof(struct tcpdiag_meminfo)+
+				    sizeof(struct tcp_info)+64), GFP_KERNEL);
+	if (!rep)
+		goto out;
+
+	if (tcpdiag_fill(rep, sk, req->tcpdiag_ext,
+			 NETLINK_CB(in_skb).pid,
+			 nlh->nlmsg_seq, 0) <= 0)
+		BUG();
+
+	err = netlink_unicast(tcpnl, rep, NETLINK_CB(in_skb).pid, MSG_DONTWAIT);
+	if (err > 0)
+		err = 0;
+
+out:
+	if (sk) {
+		if (sk->sk_state == TCP_TIME_WAIT)
+			tcp_tw_put((struct tcp_tw_bucket*)sk);
+		else
+			sock_put(sk);
+	}
+	return err;
+}
+
+static int bitstring_match(const u32 *a1, const u32 *a2, int bits)
+{
+	int words = bits >> 5;
+
+	bits &= 0x1f;
+
+	if (words) {
+		if (memcmp(a1, a2, words << 2))
+			return 0;
+	}
+	if (bits) {
+		__u32 w1, w2;
+		__u32 mask;
+
+		w1 = a1[words];
+		w2 = a2[words];
+
+		mask = htonl((0xffffffff) << (32 - bits));
+
+		if ((w1 ^ w2) & mask)
+			return 0;
+	}
+
+	return 1;
+}
+
+
+static int tcpdiag_bc_run(const void *bc, int len,
+			  const struct tcpdiag_entry *entry)
+{
+	while (len > 0) {
+		int yes = 1;
+		const struct tcpdiag_bc_op *op = bc;
+
+		switch (op->code) {
+		case TCPDIAG_BC_NOP:
+			break;
+		case TCPDIAG_BC_JMP:
+			yes = 0;
+			break;
+		case TCPDIAG_BC_S_GE:
+			yes = entry->sport >= op[1].no;
+			break;
+		case TCPDIAG_BC_S_LE:
+			yes = entry->dport <= op[1].no;
+			break;
+		case TCPDIAG_BC_D_GE:
+			yes = entry->dport >= op[1].no;
+			break;
+		case TCPDIAG_BC_D_LE:
+			yes = entry->dport <= op[1].no;
+			break;
+		case TCPDIAG_BC_AUTO:
+			yes = !(entry->userlocks & SOCK_BINDPORT_LOCK);
+			break;
+		case TCPDIAG_BC_S_COND:
+		case TCPDIAG_BC_D_COND:
+		{
+			struct tcpdiag_hostcond *cond = (struct tcpdiag_hostcond*)(op+1);
+			u32 *addr;
+
+			if (cond->port != -1 &&
+			    cond->port != (op->code == TCPDIAG_BC_S_COND ?
+					     entry->sport : entry->dport)) {
+				yes = 0;
+				break;
+			}
+			
+			if (cond->prefix_len == 0)
+				break;
+
+			if (op->code == TCPDIAG_BC_S_COND)
+				addr = entry->saddr;
+			else
+				addr = entry->daddr;
+
+			if (bitstring_match(addr, cond->addr, cond->prefix_len))
+				break;
+			if (entry->family == AF_INET6 &&
+			    cond->family == AF_INET) {
+				if (addr[0] == 0 && addr[1] == 0 &&
+				    addr[2] == htonl(0xffff) &&
+				    bitstring_match(addr+3, cond->addr, cond->prefix_len))
+					break;
+			}
+			yes = 0;
+			break;
+		}
+		}
+
+		if (yes) { 
+			len -= op->yes;
+			bc += op->yes;
+		} else {
+			len -= op->no;
+			bc += op->no;
+		}
+	}
+	return (len == 0);
+}
+
+static int valid_cc(const void *bc, int len, int cc)
+{
+	while (len >= 0) {
+		const struct tcpdiag_bc_op *op = bc;
+
+		if (cc > len)
+			return 0;
+		if (cc == len)
+			return 1;
+		if (op->yes < 4)
+			return 0;
+		len -= op->yes;
+		bc  += op->yes;
+	}
+	return 0;
+}
+
+static int tcpdiag_bc_audit(const void *bytecode, int bytecode_len)
+{
+	const unsigned char *bc = bytecode;
+	int  len = bytecode_len;
+
+	while (len > 0) {
+		struct tcpdiag_bc_op *op = (struct tcpdiag_bc_op*)bc;
+
+//printk("BC: %d %d %d {%d} / %d\n", op->code, op->yes, op->no, op[1].no, len);
+		switch (op->code) {
+		case TCPDIAG_BC_AUTO:
+		case TCPDIAG_BC_S_COND:
+		case TCPDIAG_BC_D_COND:
+		case TCPDIAG_BC_S_GE:
+		case TCPDIAG_BC_S_LE:
+		case TCPDIAG_BC_D_GE:
+		case TCPDIAG_BC_D_LE:
+			if (op->yes < 4 || op->yes > len+4)
+				return -EINVAL;
+		case TCPDIAG_BC_JMP:
+			if (op->no < 4 || op->no > len+4)
+				return -EINVAL;
+			if (op->no < len &&
+			    !valid_cc(bytecode, bytecode_len, len-op->no))
+				return -EINVAL;
+			break;
+		case TCPDIAG_BC_NOP:
+			if (op->yes < 4 || op->yes > len+4)
+				return -EINVAL;
+			break;
+		default:
+			return -EINVAL;
+		}
+		bc += op->yes;
+		len -= op->yes;
+	}
+	return len == 0 ? 0 : -EINVAL;
+}
+
+static int tcpdiag_dump_sock(struct sk_buff *skb, struct sock *sk,
+			     struct netlink_callback *cb)
+{
+	struct tcpdiagreq *r = NLMSG_DATA(cb->nlh);
+
+	if (cb->nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(*r))) {
+		struct tcpdiag_entry entry;
+		struct rtattr *bc = (struct rtattr *)(r + 1);
+		struct inet_sock *inet = inet_sk(sk);
+
+		entry.family = sk->sk_family;
+#ifdef CONFIG_IP_TCPDIAG_IPV6
+		if (entry.family == AF_INET6) {
+			struct ipv6_pinfo *np = inet6_sk(sk);
+
+			entry.saddr = np->rcv_saddr.s6_addr32;
+			entry.daddr = np->daddr.s6_addr32;
+		} else
+#endif
+		{
+			entry.saddr = &inet->rcv_saddr;
+			entry.daddr = &inet->daddr;
+		}
+		entry.sport = inet->num;
+		entry.dport = ntohs(inet->dport);
+		entry.userlocks = sk->sk_userlocks;
+
+		if (!tcpdiag_bc_run(RTA_DATA(bc), RTA_PAYLOAD(bc), &entry))
+			return 0;
+	}
+
+	return tcpdiag_fill(skb, sk, r->tcpdiag_ext, NETLINK_CB(cb->skb).pid,
+			    cb->nlh->nlmsg_seq, NLM_F_MULTI);
+}
+
+static int tcpdiag_fill_req(struct sk_buff *skb, struct sock *sk,
+			    struct open_request *req,
+			    u32 pid, u32 seq)
+{
+	struct inet_sock *inet = inet_sk(sk);
+	unsigned char *b = skb->tail;
+	struct tcpdiagmsg *r;
+	struct nlmsghdr *nlh;
+	long tmo;
+
+	nlh = NLMSG_PUT(skb, pid, seq, TCPDIAG_GETSOCK, sizeof(*r));
+	nlh->nlmsg_flags = NLM_F_MULTI;
+	r = NLMSG_DATA(nlh);
+
+	r->tcpdiag_family = sk->sk_family;
+	r->tcpdiag_state = TCP_SYN_RECV;
+	r->tcpdiag_timer = 1;
+	r->tcpdiag_retrans = req->retrans;
+
+	r->id.tcpdiag_if = sk->sk_bound_dev_if;
+	r->id.tcpdiag_cookie[0] = (u32)(unsigned long)req;
+	r->id.tcpdiag_cookie[1] = (u32)(((unsigned long)req >> 31) >> 1);
+
+	tmo = req->expires - jiffies;
+	if (tmo < 0)
+		tmo = 0;
+
+	r->id.tcpdiag_sport = inet->sport;
+	r->id.tcpdiag_dport = req->rmt_port;
+	r->id.tcpdiag_src[0] = req->af.v4_req.loc_addr;
+	r->id.tcpdiag_dst[0] = req->af.v4_req.rmt_addr;
+	r->tcpdiag_expires = jiffies_to_msecs(tmo),
+	r->tcpdiag_rqueue = 0;
+	r->tcpdiag_wqueue = 0;
+	r->tcpdiag_uid = sock_i_uid(sk);
+	r->tcpdiag_inode = 0;
+#ifdef CONFIG_IP_TCPDIAG_IPV6
+	if (r->tcpdiag_family == AF_INET6) {
+		ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_src,
+			       &req->af.v6_req.loc_addr);
+		ipv6_addr_copy((struct in6_addr *)r->id.tcpdiag_dst,
+			       &req->af.v6_req.rmt_addr);
+	}
+#endif
+	nlh->nlmsg_len = skb->tail - b;
+
+	return skb->len;
+
+nlmsg_failure:
+	skb_trim(skb, b - skb->data);
+	return -1;
+}
+
+static int tcpdiag_dump_reqs(struct sk_buff *skb, struct sock *sk,
+			     struct netlink_callback *cb)
+{
+	struct tcpdiag_entry entry;
+	struct tcpdiagreq *r = NLMSG_DATA(cb->nlh);
+	struct tcp_sock *tp = tcp_sk(sk);
+	struct tcp_listen_opt *lopt;
+	struct rtattr *bc = NULL;
+	struct inet_sock *inet = inet_sk(sk);
+	int j, s_j;
+	int reqnum, s_reqnum;
+	int err = 0;
+
+	s_j = cb->args[3];
+	s_reqnum = cb->args[4];
+
+	if (s_j > 0)
+		s_j--;
+
+	entry.family = sk->sk_family;
+
+	read_lock_bh(&tp->syn_wait_lock);
+
+	lopt = tp->listen_opt;
+	if (!lopt || !lopt->qlen)
+		goto out;
+
+	if (cb->nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(*r))) {
+		bc = (struct rtattr *)(r + 1);
+		entry.sport = inet->num;
+		entry.userlocks = sk->sk_userlocks;
+	}
+
+	for (j = s_j; j < TCP_SYNQ_HSIZE; j++) {
+		struct open_request *req, *head = lopt->syn_table[j];
+
+		reqnum = 0;
+		for (req = head; req; reqnum++, req = req->dl_next) {
+			if (reqnum < s_reqnum)
+				continue;
+			if (r->id.tcpdiag_dport != req->rmt_port &&
+			    r->id.tcpdiag_dport)
+				continue;
+
+			if (bc) {
+				entry.saddr =
+#ifdef CONFIG_IP_TCPDIAG_IPV6
+					(entry.family == AF_INET6) ?
+					req->af.v6_req.loc_addr.s6_addr32 :
+#endif
+					&req->af.v4_req.loc_addr;
+				entry.daddr = 
+#ifdef CONFIG_IP_TCPDIAG_IPV6
+					(entry.family == AF_INET6) ?
+					req->af.v6_req.rmt_addr.s6_addr32 :
+#endif
+					&req->af.v4_req.rmt_addr;
+				entry.dport = ntohs(req->rmt_port);
+
+				if (!tcpdiag_bc_run(RTA_DATA(bc),
+						    RTA_PAYLOAD(bc), &entry))
+					continue;
+			}
+
+			err = tcpdiag_fill_req(skb, sk, req,
+					       NETLINK_CB(cb->skb).pid,
+					       cb->nlh->nlmsg_seq);
+			if (err < 0) {
+				cb->args[3] = j + 1;
+				cb->args[4] = reqnum;
+				goto out;
+			}
+		}
+
+		s_reqnum = 0;
+	}
+
+out:
+	read_unlock_bh(&tp->syn_wait_lock);
+
+	return err;
+}
+
+static int tcpdiag_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	int i, num;
+	int s_i, s_num;
+	struct tcpdiagreq *r = NLMSG_DATA(cb->nlh);
+
+	s_i = cb->args[1];
+	s_num = num = cb->args[2];
+
+	if (cb->args[0] == 0) {
+		if (!(r->tcpdiag_states&(TCPF_LISTEN|TCPF_SYN_RECV)))
+			goto skip_listen_ht;
+		tcp_listen_lock();
+		for (i = s_i; i < TCP_LHTABLE_SIZE; i++) {
+			struct sock *sk;
+			struct hlist_node *node;
+
+			num = 0;
+			sk_for_each(sk, node, &tcp_listening_hash[i]) {
+				struct inet_sock *inet = inet_sk(sk);
+
+				if (num < s_num) {
+					num++;
+					continue;
+				}
+
+				if (r->id.tcpdiag_sport != inet->sport &&
+				    r->id.tcpdiag_sport)
+					goto next_listen;
+
+				if (!(r->tcpdiag_states&TCPF_LISTEN) ||
+				    r->id.tcpdiag_dport ||
+				    cb->args[3] > 0)
+					goto syn_recv;
+
+				if (tcpdiag_dump_sock(skb, sk, cb) < 0) {
+					tcp_listen_unlock();
+					goto done;
+				}
+
+syn_recv:
+				if (!(r->tcpdiag_states&TCPF_SYN_RECV))
+					goto next_listen;
+
+				if (tcpdiag_dump_reqs(skb, sk, cb) < 0) {
+					tcp_listen_unlock();
+					goto done;
+				}
+
+next_listen:
+				cb->args[3] = 0;
+				cb->args[4] = 0;
+				++num;
+			}
+
+			s_num = 0;
+			cb->args[3] = 0;
+			cb->args[4] = 0;
+		}
+		tcp_listen_unlock();
+skip_listen_ht:
+		cb->args[0] = 1;
+		s_i = num = s_num = 0;
+	}
+
+	if (!(r->tcpdiag_states&~(TCPF_LISTEN|TCPF_SYN_RECV)))
+		return skb->len;
+
+	for (i = s_i; i < tcp_ehash_size; i++) {
+		struct tcp_ehash_bucket *head = &tcp_ehash[i];
+		struct sock *sk;
+		struct hlist_node *node;
+
+		if (i > s_i)
+			s_num = 0;
+
+		read_lock_bh(&head->lock);
+
+		num = 0;
+		sk_for_each(sk, node, &head->chain) {
+			struct inet_sock *inet = inet_sk(sk);
+
+			if (num < s_num)
+				goto next_normal;
+			if (!(r->tcpdiag_states & (1 << sk->sk_state)))
+				goto next_normal;
+			if (r->id.tcpdiag_sport != inet->sport &&
+			    r->id.tcpdiag_sport)
+				goto next_normal;
+			if (r->id.tcpdiag_dport != inet->dport && r->id.tcpdiag_dport)
+				goto next_normal;
+			if (tcpdiag_dump_sock(skb, sk, cb) < 0) {
+				read_unlock_bh(&head->lock);
+				goto done;
+			}
+next_normal:
+			++num;
+		}
+
+		if (r->tcpdiag_states&TCPF_TIME_WAIT) {
+			sk_for_each(sk, node,
+				    &tcp_ehash[i + tcp_ehash_size].chain) {
+				struct inet_sock *inet = inet_sk(sk);
+
+				if (num < s_num)
+					goto next_dying;
+				if (r->id.tcpdiag_sport != inet->sport &&
+				    r->id.tcpdiag_sport)
+					goto next_dying;
+				if (r->id.tcpdiag_dport != inet->dport &&
+				    r->id.tcpdiag_dport)
+					goto next_dying;
+				if (tcpdiag_dump_sock(skb, sk, cb) < 0) {
+					read_unlock_bh(&head->lock);
+					goto done;
+				}
+next_dying:
+				++num;
+			}
+		}
+		read_unlock_bh(&head->lock);
+	}
+
+done:
+	cb->args[1] = i;
+	cb->args[2] = num;
+	return skb->len;
+}
+
+static int tcpdiag_dump_done(struct netlink_callback *cb)
+{
+	return 0;
+}
+
+
+static __inline__ int
+tcpdiag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+	if (!(nlh->nlmsg_flags&NLM_F_REQUEST))
+		return 0;
+
+	if (nlh->nlmsg_type != TCPDIAG_GETSOCK)
+		goto err_inval;
+
+	if (NLMSG_LENGTH(sizeof(struct tcpdiagreq)) > skb->len)
+		goto err_inval;
+
+	if (nlh->nlmsg_flags&NLM_F_DUMP) {
+		if (nlh->nlmsg_len > 4 + NLMSG_SPACE(sizeof(struct tcpdiagreq))) {
+			struct rtattr *rta = (struct rtattr*)(NLMSG_DATA(nlh) + sizeof(struct tcpdiagreq));
+			if (rta->rta_type != TCPDIAG_REQ_BYTECODE ||
+			    rta->rta_len < 8 ||
+			    rta->rta_len > nlh->nlmsg_len - NLMSG_SPACE(sizeof(struct tcpdiagreq)))
+				goto err_inval;
+			if (tcpdiag_bc_audit(RTA_DATA(rta), RTA_PAYLOAD(rta)))
+				goto err_inval;
+		}
+		return netlink_dump_start(tcpnl, skb, nlh,
+					  tcpdiag_dump,
+					  tcpdiag_dump_done);
+	} else {
+		return tcpdiag_get_exact(skb, nlh);
+	}
+
+err_inval:
+	return -EINVAL;
+}
+
+
+static inline void tcpdiag_rcv_skb(struct sk_buff *skb)
+{
+	int err;
+	struct nlmsghdr * nlh;
+
+	if (skb->len >= NLMSG_SPACE(0)) {
+		nlh = (struct nlmsghdr *)skb->data;
+		if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
+			return;
+		err = tcpdiag_rcv_msg(skb, nlh);
+		if (err || nlh->nlmsg_flags & NLM_F_ACK) 
+			netlink_ack(skb, nlh, err);
+	}
+}
+
+static void tcpdiag_rcv(struct sock *sk, int len)
+{
+	struct sk_buff *skb;
+
+	while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+		tcpdiag_rcv_skb(skb);
+		kfree_skb(skb);
+	}
+}
+
+static int __init tcpdiag_init(void)
+{
+	tcpnl = netlink_kernel_create(NETLINK_TCPDIAG, tcpdiag_rcv);
+	if (tcpnl == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
+static void __exit tcpdiag_exit(void)
+{
+	sock_release(tcpnl->sk_socket);
+}
+
+module_init(tcpdiag_init);
+module_exit(tcpdiag_exit);
+MODULE_LICENSE("GPL");