src/tcp.c - manifest_repos/conntrack-tools - Git at Google

 /*
  * (C) 2009 by Pablo Neira Ayuso <pablo@netfilter.org>
  *
  * 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.
  *
  * TCP support has been sponsored by 6WIND <www.6wind.com>.
  */

 #include "tcp.h"

 #include <stdio.h>
 #include <stdlib.h>
 #include <arpa/inet.h>
 #include <unistd.h>
 #include <string.h>
 #include <sys/ioctl.h>
 #include <net/if.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <limits.h>

 #include "conntrackd.h"
 #include "fds.h"

 struct tcp_sock *tcp_server_create(struct tcp_conf *c)
 {
 	int yes = 1;
 	struct tcp_sock *m;
 	socklen_t socklen = sizeof(int);

 	m = calloc(sizeof(struct tcp_sock), 1);
 	if (m == NULL)
 		return NULL;

 	m->conf = c;

 	switch(c->ipproto) {
 	case AF_INET:
 	        m->addr.ipv4.sin_family = AF_INET;
 	        m->addr.ipv4.sin_port = htons(c->port);
 	        m->addr.ipv4.sin_addr = c->server.ipv4.inet_addr;
 		m->sockaddr_len = sizeof(struct sockaddr_in);
 		break;

 	case AF_INET6:
 		m->addr.ipv6.sin6_family = AF_INET6;
 		m->addr.ipv6.sin6_port = htons(c->port);
 		m->addr.ipv6.sin6_addr = c->server.ipv6.inet_addr6;
 		m->addr.ipv6.sin6_scope_id = c->server.ipv6.scope_id;
 		m->sockaddr_len = sizeof(struct sockaddr_in6);
 		break;
 	}

 	m->fd = socket(c->ipproto, SOCK_STREAM, 0);
 	if (m->fd == -1) {
 		free(m);
 		return NULL;
 	}

 	if (setsockopt(m->fd, SOL_SOCKET, SO_REUSEADDR, &yes,
 				sizeof(int)) == -1) {
 		close(m->fd);
 		free(m);
 		return NULL;
 	}

 	if (setsockopt(m->fd, SOL_SOCKET, SO_KEEPALIVE, &yes,
 				sizeof(int)) == -1) {
 		close(m->fd);
 		free(m);
 		return NULL;
 	}

 #ifndef SO_RCVBUFFORCE
 #define SO_RCVBUFFORCE 33
 #endif

 	if (c->rcvbuf &&
 	    setsockopt(m->fd, SOL_SOCKET, SO_RCVBUFFORCE, &c->rcvbuf,
 				sizeof(int)) == -1) {
 		/* not supported in linux kernel < 2.6.14 */
 		if (errno != ENOPROTOOPT) {
 			close(m->fd);
 			free(m);
 			return NULL;
 		}
 	}

 	getsockopt(m->fd, SOL_SOCKET, SO_RCVBUF, &c->rcvbuf, &socklen);

 	if (bind(m->fd, (struct sockaddr *) &m->addr, m->sockaddr_len) == -1) {
 		close(m->fd);
 		free(m);
 		return NULL;
 	}

 	if (listen(m->fd, 1) == -1) {
 		close(m->fd);
 		free(m);
 		return NULL;
 	}

 	if (fcntl(m->fd, F_SETFL, O_NONBLOCK) == -1) {
 		close(m->fd);
 		free(m);
 		return NULL;
 	}

 	m->state = TCP_SERVER_ACCEPTING;

 	return m;
 }

 void tcp_server_destroy(struct tcp_sock *m)
 {
 	close(m->fd);
 	free(m);
 }

 static int
 tcp_client_init(struct tcp_sock *m, struct tcp_conf *c)
 {
 	int ret = 0;
 	socklen_t socklen = sizeof(int);

 	m->fd = socket(c->ipproto, SOCK_STREAM, 0);
 	if (m->fd == -1)
 		return -1;

 	if (setsockopt(m->fd, SOL_SOCKET, SO_NO_CHECK, &c->checksum,
 				sizeof(int)) == -1) {
 		close(m->fd);
 		return -1;
 	}

 #ifndef SO_SNDBUFFORCE
 #define SO_SNDBUFFORCE 32
 #endif

 	if (c->sndbuf &&
 	    setsockopt(m->fd, SOL_SOCKET, SO_SNDBUFFORCE, &c->sndbuf,
 				sizeof(int)) == -1) {
 		/* not supported in linux kernel < 2.6.14 */
 		if (errno != ENOPROTOOPT) {
 			close(m->fd);
 			return -1;
 		}
 	}

 	getsockopt(m->fd, SOL_SOCKET, SO_SNDBUF, &c->sndbuf, &socklen);

 	switch(c->ipproto) {
 	case AF_INET:
 		m->addr.ipv4.sin_family = AF_INET;
 		m->addr.ipv4.sin_port = htons(c->port);
 		m->addr.ipv4.sin_addr = c->client.inet_addr;
 		m->sockaddr_len = sizeof(struct sockaddr_in);
 		break;
 	case AF_INET6:
 		m->addr.ipv6.sin6_family = AF_INET6;
 		m->addr.ipv6.sin6_port = htons(c->port);
 		memcpy(&m->addr.ipv6.sin6_addr, &c->client.inet_addr6,
 		       sizeof(struct in6_addr));
 		m->sockaddr_len = sizeof(struct sockaddr_in6);
 		break;
 	default:
 		ret = -1;
 		break;
 	}

 	if (ret == -1) {
 		close(m->fd);
 		return -1;
 	}

 	if (fcntl(m->fd, F_SETFL, O_NONBLOCK) == -1) {
 		close(m->fd);
 		return -1;
 	}

 	ret = connect(m->fd, (struct sockaddr *)&m->addr, m->sockaddr_len);
 	if (ret == -1) {
 		if (errno == EINPROGRESS) {
 			/* connection in progress ... */
 			m->state = TCP_CLIENT_DISCONNECTED;
 		} else if (errno == ECONNREFUSED) {
 			/* connection refused. */
 			m->state = TCP_CLIENT_DISCONNECTED;
 		} else {
 			/* unexpected error, give up. */
 			close(m->fd);
 			return -1;
 		}
 	} else {
 		/* very unlikely at this stage. */
 		m->state = TCP_CLIENT_CONNECTED;
 	}
 	return 0;
 }

 /* We use this to rate-limit the amount of connect() calls per second. */
 static struct alarm_block tcp_connect_alarm;
 static void tcp_connect_alarm_cb(struct alarm_block *a, void *data) {}

 struct tcp_sock *tcp_client_create(struct tcp_conf *c)
 {
 	struct tcp_sock *m;

 	m = calloc(sizeof(struct tcp_sock), 1);
 	if (m == NULL)
 		return NULL;

 	m->conf = c;

 	if (tcp_client_init(m, c) == -1) {
 		free(m);
 		return NULL;
 	}

 	init_alarm(&tcp_connect_alarm, NULL, tcp_connect_alarm_cb);

 	return m;
 }

 void tcp_client_destroy(struct tcp_sock *m)
 {
 	close(m->fd);
 	free(m);
 }

 int tcp_accept(struct tcp_sock *m)
 {
 	int ret;

 	/* we got an attempt to connect but we already have a client? */
 	if (m->state != TCP_SERVER_ACCEPTING) {
 		/* clear the session and restart ... */
 		unregister_fd(m->client_fd, STATE(fds));
 		close(m->client_fd);
 		m->client_fd = -1;
 		m->state = TCP_SERVER_ACCEPTING;
 	}

 	/* the other peer wants to connect ... */
 	ret = accept(m->fd, NULL, NULL);
 	if (ret == -1) {
 		/* unexpected error: Give us another try. Or we have hit
  		 * -EAGAIN, in that case we remain in the accepting connections
 		 * state.
 		 */
 		m->state = TCP_SERVER_ACCEPTING;
 	} else {
 		/* the peer finally got connected. */
 		if (fcntl(ret, F_SETFL, O_NONBLOCK) == -1) {
 			/* close the connection and give us another chance. */
 			close(ret);
 			return -1;
 		}

 		m->client_fd = ret;
 		m->state = TCP_SERVER_CONNECTED;
 	}
 	return m->client_fd;
 }

 #define TCP_CONNECT_TIMEOUT	1

 ssize_t tcp_send(struct tcp_sock *m, const void *data, int size)
 {
 	ssize_t ret = 0;

 	switch(m->state) {
 	case TCP_CLIENT_DISCONNECTED:
 		/* We rate-limit the amount of connect() calls. */
 		if (alarm_pending(&tcp_connect_alarm)) {
 			ret = -1;
 			break;
 		}
 		add_alarm(&tcp_connect_alarm, TCP_CONNECT_TIMEOUT, 0);
 		ret = connect(m->fd, (struct sockaddr *)&m->addr,
 			      m->sockaddr_len);
 		if (ret == -1) {
 			if (errno == EINPROGRESS || errno == EALREADY) {
 				/* connection in progress or already trying. */
 				m->state = TCP_CLIENT_DISCONNECTED;
 			} else if (errno == ECONNREFUSED) {
 				/* connection refused. */
 				m->state = TCP_CLIENT_DISCONNECTED;
 				m->stats.error++;
 			} else {
 				/* unexpected error, give up. */
 				m->state = TCP_CLIENT_DISCONNECTED;
 				m->stats.error++;
 			}
 			break;
 		} else {
 			/* we got connected :) */
 			m->state = TCP_CLIENT_CONNECTED;
 		}
 	case TCP_CLIENT_CONNECTED:
 		ret = sendto(m->fd, data, size, 0,
 			     (struct sockaddr *) &m->addr, m->sockaddr_len);
 		if (ret == -1) {
 			if (errno == EPIPE || errno == ECONNRESET) {
 				close(m->fd);
 				tcp_client_init(m, m->conf);
 				m->state = TCP_CLIENT_DISCONNECTED;
 				m->stats.error++;
 			} else {
 				m->stats.error++;
 				return -1;
 			}
 		}
 	}

 	if (ret >= 0) {
 		m->stats.bytes += ret;
 		m->stats.messages++;
 	}
 	return ret;
 }

 ssize_t tcp_recv(struct tcp_sock *m, void *data, int size)
 {
 	ssize_t ret = 0;
 	socklen_t sin_size = sizeof(struct sockaddr_in);

 	/* we are not connected, skip. */
 	if (m->state != TCP_SERVER_CONNECTED)
 		return 0;

         ret = recvfrom(m->client_fd, data, size, 0,
 		       (struct sockaddr *)&m->addr, &sin_size);
 	if (ret == -1) {
 		/* the other peer has disconnected... */
 		if (errno == ENOTCONN) {
 			unregister_fd(m->client_fd, STATE(fds));
 			close(m->client_fd);
 			m->client_fd = -1;
 			m->state = TCP_SERVER_ACCEPTING;
 		} else if (errno != EAGAIN) {
 			m->stats.error++;
 		}
 	} else if (ret == 0) {
 		/* the other peer has closed the connection... */
 		unregister_fd(m->client_fd, STATE(fds));
 		close(m->client_fd);
 		m->client_fd = -1;
 		m->state = TCP_SERVER_ACCEPTING;
 	}

 	if (ret >= 0) {
 		m->stats.bytes += ret;
 		m->stats.messages++;
 	}
 	return ret;
 }

 int tcp_get_fd(struct tcp_sock *m)
 {
 	return m->fd;
 }

 int tcp_isset(struct tcp_sock *m, fd_set *readfds)
 {
 	return m->client_fd >= 0 ? FD_ISSET(m->client_fd, readfds) : 0;
 }

 int tcp_accept_isset(struct tcp_sock *m, fd_set *readfds)
 {
 	return FD_ISSET(m->fd, readfds);
 }

 int
 tcp_snprintf_stats(char *buf, size_t buflen, char *ifname,
 		   struct tcp_sock *client, struct tcp_sock *server)
 {
 	size_t size;
 	struct tcp_stats *s = &client->stats, *r = &server->stats;

 	size = snprintf(buf, buflen, "TCP traffic (active device=%s) "
 				     "server=%s client=%s:\n"
 				     "%20llu Bytes sent "
 				     "%20llu Bytes recv\n"
 				     "%20llu Pckts sent "
 				     "%20llu Pckts recv\n"
 				     "%20llu Error send "
 				     "%20llu Error recv\n\n",
 				     ifname,
 				     server->state == TCP_SERVER_CONNECTED ?
 				     "connected" : "disconnected",
 				     client->state == TCP_CLIENT_CONNECTED ?
 				     "connected" : "disconnected",
 				     (unsigned long long)s->bytes,
 				     (unsigned long long)r->bytes,
 				     (unsigned long long)s->messages,
 				     (unsigned long long)r->messages,
 				     (unsigned long long)s->error,
 				     (unsigned long long)r->error);
 	return size;
 }

 int
 tcp_snprintf_stats2(char *buf, size_t buflen, const char *ifname,
 		    const char *status, int active,
 		    struct tcp_stats *s, struct tcp_stats *r)
 {
 	size_t size;

 	size = snprintf(buf, buflen,
 			"TCP traffic device=%s status=%s role=%s:\n"
 			"%20llu Bytes sent "
 			"%20llu Bytes recv\n"
 			"%20llu Pckts sent "
 			"%20llu Pckts recv\n"
 			"%20llu Error send "
 			"%20llu Error recv\n\n",
 			ifname, status, active ? "ACTIVE" : "BACKUP",
 			(unsigned long long)s->bytes,
 			(unsigned long long)r->bytes,
 			(unsigned long long)s->messages,
 			(unsigned long long)r->messages,
 			(unsigned long long)s->error,
 			(unsigned long long)r->error);
 	return size;
 }
	/*
	* (C) 2009 by Pablo Neira Ayuso <pablo@netfilter.org>
	*
	* 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.
	*
	* TCP support has been sponsored by 6WIND <www.6wind.com>.
	*/

	#include "tcp.h"

	#include <stdio.h>
	#include <stdlib.h>
	#include <arpa/inet.h>
	#include <unistd.h>
	#include <string.h>
	#include <sys/ioctl.h>
	#include <net/if.h>
	#include <errno.h>
	#include <fcntl.h>
	#include <limits.h>

	#include "conntrackd.h"
	#include "fds.h"

	struct tcp_sock tcp_server_create(struct tcp_conf c)
	{
	int yes = 1;
	struct tcp_sock *m;
	socklen_t socklen = sizeof(int);

	m = calloc(sizeof(struct tcp_sock), 1);
	if (m == NULL)
	return NULL;

	m->conf = c;

	switch(c->ipproto) {
	case AF_INET:
	m->addr.ipv4.sin_family = AF_INET;
	m->addr.ipv4.sin_port = htons(c->port);
	m->addr.ipv4.sin_addr = c->server.ipv4.inet_addr;
	m->sockaddr_len = sizeof(struct sockaddr_in);
	break;

	case AF_INET6:
	m->addr.ipv6.sin6_family = AF_INET6;
	m->addr.ipv6.sin6_port = htons(c->port);
	m->addr.ipv6.sin6_addr = c->server.ipv6.inet_addr6;
	m->addr.ipv6.sin6_scope_id = c->server.ipv6.scope_id;
	m->sockaddr_len = sizeof(struct sockaddr_in6);
	break;
	}

	m->fd = socket(c->ipproto, SOCK_STREAM, 0);
	if (m->fd == -1) {
	free(m);
	return NULL;
	}

	if (setsockopt(m->fd, SOL_SOCKET, SO_REUSEADDR, &yes,
	sizeof(int)) == -1) {
	close(m->fd);
	free(m);
	return NULL;
	}

	if (setsockopt(m->fd, SOL_SOCKET, SO_KEEPALIVE, &yes,
	sizeof(int)) == -1) {
	close(m->fd);
	free(m);
	return NULL;
	}

	#ifndef SO_RCVBUFFORCE
	#define SO_RCVBUFFORCE 33
	#endif

	if (c->rcvbuf &&
	setsockopt(m->fd, SOL_SOCKET, SO_RCVBUFFORCE, &c->rcvbuf,
	sizeof(int)) == -1) {
	/* not supported in linux kernel < 2.6.14 */
	if (errno != ENOPROTOOPT) {
	close(m->fd);
	free(m);
	return NULL;
	}
	}

	getsockopt(m->fd, SOL_SOCKET, SO_RCVBUF, &c->rcvbuf, &socklen);

	if (bind(m->fd, (struct sockaddr *) &m->addr, m->sockaddr_len) == -1) {
	close(m->fd);
	free(m);
	return NULL;
	}

	if (listen(m->fd, 1) == -1) {
	close(m->fd);
	free(m);
	return NULL;
	}

	if (fcntl(m->fd, F_SETFL, O_NONBLOCK) == -1) {
	close(m->fd);
	free(m);
	return NULL;
	}

	m->state = TCP_SERVER_ACCEPTING;

	return m;
	}

	void tcp_server_destroy(struct tcp_sock *m)
	{
	close(m->fd);
	free(m);
	}

	static int
	tcp_client_init(struct tcp_sock m, struct tcp_conf c)
	{
	int ret = 0;
	socklen_t socklen = sizeof(int);

	m->fd = socket(c->ipproto, SOCK_STREAM, 0);
	if (m->fd == -1)
	return -1;

	if (setsockopt(m->fd, SOL_SOCKET, SO_NO_CHECK, &c->checksum,
	sizeof(int)) == -1) {
	close(m->fd);
	return -1;
	}

	#ifndef SO_SNDBUFFORCE
	#define SO_SNDBUFFORCE 32
	#endif

	if (c->sndbuf &&
	setsockopt(m->fd, SOL_SOCKET, SO_SNDBUFFORCE, &c->sndbuf,
	sizeof(int)) == -1) {
	/* not supported in linux kernel < 2.6.14 */
	if (errno != ENOPROTOOPT) {
	close(m->fd);
	return -1;
	}
	}

	getsockopt(m->fd, SOL_SOCKET, SO_SNDBUF, &c->sndbuf, &socklen);

	switch(c->ipproto) {
	case AF_INET:
	m->addr.ipv4.sin_family = AF_INET;
	m->addr.ipv4.sin_port = htons(c->port);
	m->addr.ipv4.sin_addr = c->client.inet_addr;
	m->sockaddr_len = sizeof(struct sockaddr_in);
	break;
	case AF_INET6:
	m->addr.ipv6.sin6_family = AF_INET6;
	m->addr.ipv6.sin6_port = htons(c->port);
	memcpy(&m->addr.ipv6.sin6_addr, &c->client.inet_addr6,
	sizeof(struct in6_addr));
	m->sockaddr_len = sizeof(struct sockaddr_in6);
	break;
	default:
	ret = -1;
	break;
	}

	if (ret == -1) {
	close(m->fd);
	return -1;
	}

	if (fcntl(m->fd, F_SETFL, O_NONBLOCK) == -1) {
	close(m->fd);
	return -1;
	}

	ret = connect(m->fd, (struct sockaddr *)&m->addr, m->sockaddr_len);
	if (ret == -1) {
	if (errno == EINPROGRESS) {
	/* connection in progress ... */
	m->state = TCP_CLIENT_DISCONNECTED;
	} else if (errno == ECONNREFUSED) {
	/* connection refused. */
	m->state = TCP_CLIENT_DISCONNECTED;
	} else {
	/* unexpected error, give up. */
	close(m->fd);
	return -1;
	}
	} else {
	/* very unlikely at this stage. */
	m->state = TCP_CLIENT_CONNECTED;
	}
	return 0;
	}

	/* We use this to rate-limit the amount of connect() calls per second. */
	static struct alarm_block tcp_connect_alarm;
	static void tcp_connect_alarm_cb(struct alarm_block a, void data) {}

	struct tcp_sock tcp_client_create(struct tcp_conf c)
	{
	struct tcp_sock *m;

	m = calloc(sizeof(struct tcp_sock), 1);
	if (m == NULL)
	return NULL;

	m->conf = c;

	if (tcp_client_init(m, c) == -1) {
	free(m);
	return NULL;
	}

	init_alarm(&tcp_connect_alarm, NULL, tcp_connect_alarm_cb);

	return m;
	}

	void tcp_client_destroy(struct tcp_sock *m)
	{
	close(m->fd);
	free(m);
	}

	int tcp_accept(struct tcp_sock *m)
	{
	int ret;

	/* we got an attempt to connect but we already have a client? */
	if (m->state != TCP_SERVER_ACCEPTING) {
	/* clear the session and restart ... */
	unregister_fd(m->client_fd, STATE(fds));
	close(m->client_fd);
	m->client_fd = -1;
	m->state = TCP_SERVER_ACCEPTING;
	}

	/* the other peer wants to connect ... */
	ret = accept(m->fd, NULL, NULL);
	if (ret == -1) {
	/* unexpected error: Give us another try. Or we have hit
	* -EAGAIN, in that case we remain in the accepting connections
	* state.
	*/
	m->state = TCP_SERVER_ACCEPTING;
	} else {
	/* the peer finally got connected. */
	if (fcntl(ret, F_SETFL, O_NONBLOCK) == -1) {
	/* close the connection and give us another chance. */
	close(ret);
	return -1;
	}

	m->client_fd = ret;
	m->state = TCP_SERVER_CONNECTED;
	}
	return m->client_fd;
	}

	#define TCP_CONNECT_TIMEOUT 1

	ssize_t tcp_send(struct tcp_sock m, const void data, int size)
	{
	ssize_t ret = 0;

	switch(m->state) {
	case TCP_CLIENT_DISCONNECTED:
	/* We rate-limit the amount of connect() calls. */
	if (alarm_pending(&tcp_connect_alarm)) {
	ret = -1;
	break;
	}
	add_alarm(&tcp_connect_alarm, TCP_CONNECT_TIMEOUT, 0);
	ret = connect(m->fd, (struct sockaddr *)&m->addr,
	m->sockaddr_len);
	if (ret == -1) {
	if (errno == EINPROGRESS \|\| errno == EALREADY) {
	/* connection in progress or already trying. */
	m->state = TCP_CLIENT_DISCONNECTED;
	} else if (errno == ECONNREFUSED) {
	/* connection refused. */
	m->state = TCP_CLIENT_DISCONNECTED;
	m->stats.error++;
	} else {
	/* unexpected error, give up. */
	m->state = TCP_CLIENT_DISCONNECTED;
	m->stats.error++;
	}
	break;
	} else {
	/* we got connected :) */
	m->state = TCP_CLIENT_CONNECTED;
	}
	case TCP_CLIENT_CONNECTED:
	ret = sendto(m->fd, data, size, 0,
	(struct sockaddr *) &m->addr, m->sockaddr_len);
	if (ret == -1) {
	if (errno == EPIPE \|\| errno == ECONNRESET) {
	close(m->fd);
	tcp_client_init(m, m->conf);
	m->state = TCP_CLIENT_DISCONNECTED;
	m->stats.error++;
	} else {
	m->stats.error++;
	return -1;
	}
	}
	}

	if (ret >= 0) {
	m->stats.bytes += ret;
	m->stats.messages++;
	}
	return ret;
	}

	ssize_t tcp_recv(struct tcp_sock m, void data, int size)
	{
	ssize_t ret = 0;
	socklen_t sin_size = sizeof(struct sockaddr_in);

	/* we are not connected, skip. */
	if (m->state != TCP_SERVER_CONNECTED)
	return 0;

	ret = recvfrom(m->client_fd, data, size, 0,
	(struct sockaddr *)&m->addr, &sin_size);
	if (ret == -1) {
	/* the other peer has disconnected... */
	if (errno == ENOTCONN) {
	unregister_fd(m->client_fd, STATE(fds));
	close(m->client_fd);
	m->client_fd = -1;
	m->state = TCP_SERVER_ACCEPTING;
	} else if (errno != EAGAIN) {
	m->stats.error++;
	}
	} else if (ret == 0) {
	/* the other peer has closed the connection... */
	unregister_fd(m->client_fd, STATE(fds));
	close(m->client_fd);
	m->client_fd = -1;
	m->state = TCP_SERVER_ACCEPTING;
	}

	if (ret >= 0) {
	m->stats.bytes += ret;
	m->stats.messages++;
	}
	return ret;
	}

	int tcp_get_fd(struct tcp_sock *m)
	{
	return m->fd;
	}

	int tcp_isset(struct tcp_sock m, fd_set readfds)
	{
	return m->client_fd >= 0 ? FD_ISSET(m->client_fd, readfds) : 0;
	}

	int tcp_accept_isset(struct tcp_sock m, fd_set readfds)
	{
	return FD_ISSET(m->fd, readfds);
	}

	int
	tcp_snprintf_stats(char buf, size_t buflen, char ifname,
	struct tcp_sock client, struct tcp_sock server)
	{
	size_t size;
	struct tcp_stats s = &client->stats, r = &server->stats;

	size = snprintf(buf, buflen, "TCP traffic (active device=%s) "
	"server=%s client=%s:\n"
	"%20llu Bytes sent "
	"%20llu Bytes recv\n"
	"%20llu Pckts sent "
	"%20llu Pckts recv\n"
	"%20llu Error send "
	"%20llu Error recv\n\n",
	ifname,
	server->state == TCP_SERVER_CONNECTED ?
	"connected" : "disconnected",
	client->state == TCP_CLIENT_CONNECTED ?
	"connected" : "disconnected",
	(unsigned long long)s->bytes,
	(unsigned long long)r->bytes,
	(unsigned long long)s->messages,
	(unsigned long long)r->messages,
	(unsigned long long)s->error,
	(unsigned long long)r->error);
	return size;
	}

	int
	tcp_snprintf_stats2(char buf, size_t buflen, const char ifname,
	const char *status, int active,
	struct tcp_stats s, struct tcp_stats r)
	{
	size_t size;

	size = snprintf(buf, buflen,
	"TCP traffic device=%s status=%s role=%s:\n"
	"%20llu Bytes sent "
	"%20llu Bytes recv\n"
	"%20llu Pckts sent "
	"%20llu Pckts recv\n"
	"%20llu Error send "
	"%20llu Error recv\n\n",
	ifname, status, active ? "ACTIVE" : "BACKUP",
	(unsigned long long)s->bytes,
	(unsigned long long)r->bytes,
	(unsigned long long)s->messages,
	(unsigned long long)r->messages,
	(unsigned long long)s->error,
	(unsigned long long)r->error);
	return size;
	}