msproxy_clientprotocol.c

sock protocol ,it is useful!

/*
 * Copyright (c) 1997, 1998, 1999
 *      Inferno Nettverk A/S, Norway.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. The above copyright notice, this list of conditions and the following
 *    disclaimer must appear in all copies of the software, derivative works
 *    or modified versions, and any portions thereof, aswell as in all
 *    supporting documentation.
 * 2. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by
 *      Inferno Nettverk A/S, Norway.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Inferno Nettverk A/S requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  [e-mail]
 *  Inferno Nettverk A/S
 *  Oslo Research Park
 *  Gaustadal閑n 21
 *  N-0349 Oslo
 *  Norway
 *
 * any improvements or extensions that they make and grant Inferno Nettverk A/S
 * the rights to redistribute these changes.
 *
 */

/*
 * This code is terrible so hopefully it will match the protocol.
 */

#include "common.h"

static const char rcsid[] =
"$Id: msproxy_clientprotocol.c,v 1.22 1999/09/02 10:41:41 michaels Exp $";

static char executable[] = "TELNET.EXE";
static struct sigaction oldsigio;

__BEGIN_DECLS

static int
msproxy_connect __P((int s, int control, struct socks_t *packet));

static int
msproxy_bind __P((int s, int control, struct socks_t *packet));

static char *
mem2response __P((struct msproxy_response_t *res, char *mem, size_t len));

static char *
request2mem __P((const struct msproxy_request_t *req, char *mem));

static void
msproxy_sessionsend __P((void));
/*
 * Terminates all msproxy sessions.
 */

static void
msproxy_sessionend __P((int s, struct msproxy_state_t *msproxy));
/*
 * ends the session negotiated with "s" and having state "msproxy".
 */

static void
msproxy_keepalive __P((int signal));
/*
 * Sends a keepalive packet on behalf of all established sessions.
 */

static void
sigio __P((int sig));

__END_DECLS

int
msproxy_init(void)
{
	const char *function = "msproxy_init()";
	struct itimerval timerval;
	struct sigaction sigact, oldsigact;

	if (atexit(msproxy_sessionsend) != 0) {
		swarn("%s: atexit()", function);
		return -1;
	}

	if (sigaction(SIGALRM, NULL, &oldsigact) != 0) {
		swarn("%s: sigaction(SIGALRM)", function);
		return -1;
	}

	/* XXX */
	if (oldsigact.sa_handler != SIG_DFL
	&&  oldsigact.sa_handler != SIG_IGN) {
		swarnx("%s: could not install signalhandler for SIGALRM, already set",
		function);
		return 0;	/* will probably timeout, don't consider it fatal for now. */
	}

	sigemptyset(&sigact.sa_mask);
	sigact.sa_flags	= SA_RESTART;
	sigact.sa_handler	= msproxy_keepalive;
	if (sigaction(SIGALRM, &sigact, NULL) != 0) {
		swarn("%s: sigaction(SIGALRM)", function);
		return -1;
	}

	timerval.it_value.tv_sec	= MSPROXY_PINGINTERVAL;
	timerval.it_value.tv_usec	= 0;
	timerval.it_interval = timerval.it_value;

	if (setitimer(ITIMER_REAL, &timerval, NULL) != 0) {
		swarn("%s: setitimer()", function);
		return -1;
	}

	srand((unsigned int)time(NULL) * getpid());

	return 0;
}

int
msproxy_negotiate(s, control, packet)
	int s;
	int control;
	struct socks_t *packet;
{
	const char *function = "msproxy_negotiate()";
	struct msproxy_request_t req;
	struct msproxy_response_t res;
	int p;

	slog(LOG_DEBUG, "%s: packet #1", function);

	bzero(&req, sizeof(req));
	req.clientid	= htonl(0x0a000000);
	req.command		= htons(MSPROXY_HELLO);

	/* in case we don't get something more sensible. */
	packet->res.version	= packet->req.version;
	packet->res.reply		= MSPROXY_FAILURE;

	switch (packet->req.command) {
		case SOCKS_BIND:
#if 1
			req.packet._1.magic5		= htons(0x4800);
			req.packet._1.magic10	= htons(0x1400);
			req.packet._1.magic15	= htons(0x0400);
			req.packet._1.magic20	= htons(0x5704);
			req.packet._1.magic25	= htons(0x0004);
			req.packet._1.magic30	= htons(0x0100);
			req.packet._1.magic35	= htons(0x4a02);
			req.packet._1.magic40	= htons(0x3000);
			req.packet._1.magic45	= htons(0x4100);
			req.packet._1.magic50	= htons(0x3900);
#endif
			break;

		case SOCKS_CONNECT:
#if 0
			req.packet._1.magic5		= htons(0x4b00);
			req.packet._1.magic10	= htons(0x1400);
			req.packet._1.magic15	= htons(0x0400);
			req.packet._1.magic20	= htons(0x5704);
			req.packet._1.magic25	= htons(0x0004);
			req.packet._1.magic30	= htons(0x0100);
			req.packet._1.magic35	= htons(0x4a02);
			req.packet._1.magic40	= htons(0x3000);
			req.packet._1.magic45	= htons(0x4400);
			req.packet._1.magic50	= htons(0x3900);
#endif
			break;

		case SOCKS_UDPASSOCIATE:
			SERRX(packet->req.command);
			/* NOTREACHED */

		default:
			SERRX(packet->req.command);
	}

	if (socks_getusername(&packet->gw.host, req.username, sizeof(req.username))
	== NULL)
		return -1;

	*req.unknown = NUL;

	strncpy(req.executable, executable, sizeof(req.executable) - 1);
	req.executable[sizeof(req.executable) - 1] = NUL;

	*req.clienthost = NUL;

#if 0
	strncpy(req.clienthost, "foo", sizeof(req.clienthost) - 1);
	req.clienthost[sizeof(req.clienthost) - 1] = NUL;
#endif

	if (send_msprequest(control, &packet->state.msproxy, &req) == -1)
		return -1;

	if (recv_mspresponse(control, &packet->state.msproxy, &res) == -1)
		return -1;

	if (strcmp(res.RWSP, "RWSP") != 0)
		serrx(EXIT_FAILURE, "expected \"RWSP\", got \"%s\"",
		str2vis(res.RWSP, sizeof(res.RWSP)));

	if (ntohs(res.command) >> 8 != 0x10)
		serrx(EXIT_FAILURE, "expected res.command = 10??, is %x",
		ntohs(res.command));

	packet->state.msproxy.controladdr.sin_family			= AF_INET;
	packet->state.msproxy.controladdr.sin_port			= res.packet._1.udpport;
	packet->state.msproxy.controladdr.sin_addr.s_addr	= res.packet._1.udpaddr;

	packet->state.msproxy.clientid	= htonl(rand());
	packet->state.msproxy.serverid	= res.serverid;

	slog(LOG_DEBUG, "%s: clientid: 0x%x, serverid: 0x%0x",
	function, packet->state.msproxy.clientid, packet->state.msproxy.serverid);

	/* LINTED pointer casts may be troublesome */
	slog(LOG_DEBUG, "%s: msproxy controladdress: %s",
	function,
	sockaddr2string((struct sockaddr *)&packet->state.msproxy.controladdr,
	NULL, 0));


	slog(LOG_DEBUG, "%s: packet #2", function);

	/* almost identical. */
	req.clientid	= packet->state.msproxy.clientid;
	req.serverid	= packet->state.msproxy.serverid;

	if (send_msprequest(control, &packet->state.msproxy, &req) == -1)
		return -1;

	if (recv_mspresponse(control, &packet->state.msproxy, &res) == -1)
		return -1;

	if (res.serverid != packet->state.msproxy.serverid)
		serrx(EXIT_FAILURE, "expected serverid = 0x%x, is 0x%x",
		packet->state.msproxy.serverid, res.serverid);

	if (res.sequence != 0x01)
		serrx(EXIT_FAILURE, "expected res.sequence = 0x%x, is 0x%x",
		0x01, res.sequence);

	if (ntohs(res.command) != MSPROXY_USERINFO_ACK)
		serrx(EXIT_FAILURE, "expected res.command = 0x%x, is 0x%x",
		MSPROXY_USERINFO_ACK, ntohs(res.command));

	switch (packet->req.command) {
		case SOCKS_BIND:
			p = msproxy_bind(s, control, packet);
			break;

		case SOCKS_CONNECT:
			p = msproxy_connect(s, control, packet);
			break;

		case SOCKS_UDPASSOCIATE:
		default:
			SERRX(packet->req.command);
	}

	return p;
}

static int
msproxy_connect(s, control, packet)
	int s;
	int control;
	struct socks_t *packet;
{
	const char *function = "msproxy_connect()";
	struct msproxy_request_t req;
	struct msproxy_response_t res;
	struct sockaddr_in addr;
	socklen_t len;

	slog(LOG_DEBUG, function);

#if 0

	bzero(&req, sizeof(req));
	req.clientid		= packet->state.msproxy.clientid;
	req.serverid		= packet->state.msproxy.serverid;
	req.command			= htons(MSPROXY_SOMETHING);
	memcpy(req.packet._3.NTLMSSP, "NTLMSSP", sizeof("NTLMSSP"));
	req.packet._3.bindaddr	= htonl(0x02000000);
	req.packet._3.magic5		= htons(0x0100);
	req.packet._3.magic10	= htons(0x9682);
#if 0
	req.packet._3.magic50	= htons(0x3000);
	req.packet._3.magic55	= htons(0x3000);
#endif

	if (send_msprequest(control, &packet->state.msproxy, &req) == -1)
		return -1;

	if (recv_mspresponse(control, &packet->state.msproxy, &res) == -1)
		return -1;

	if (res.serverid != packet->state.msproxy.serverid)
		serrx(EXIT_FAILURE, "expected serverid = 0x%x, is 0x%x",
		packet->state.msproxy.serverid, res.serverid);

	if (ntohs(res.command) != MSPROXY_SOMETHING_1_ACK)
		serrx(EXIT_FAILURE, "expected res.command = 0x%x, is 0x%x",
		MSPROXY_SOMETHING_1_ACK, ntohs(res.command));

	slog(LOG_DEBUG, "%s: ntdomain: \"%s\"", function, res.packet._3.ntdomain);


	slog(LOG_DEBUG, "%s: packet #4", function);

	bzero(&req, sizeof(req));
	req.clientid		= packet->state.msproxy.clientid;
	req.serverid		= packet->state.msproxy.serverid;
	req.command			= htons(MSPROXY_SOMETHING_2);
#if 0
	memcpy(req.packet._4.NTLMSSP, "NTLMSSP", sizeof("NTLMSSP"));
	req.packet._4.magic3			= htons(0x0200);
	req.packet._4.magic5			= htons(0x0300);
	req.packet._4.magic10		= htons(0x1800);
	req.packet._4.magic15		= htons(0x1800);
	req.packet._4.magic20		= htons(0x4900);
	req.packet._4.magic30		= htons(0x6100);
	req.packet._4.magic35		= htons(0x0800);
	req.packet._4.magic40		= htons(0x0800);
	req.packet._4.magic45		= htons(0x3400);
	req.packet._4.magic50		= htons(0x0700);
	req.packet._4.magic55		= htons(0x0700);
	req.packet._4.magic60		= htons(0x3c00);
	req.packet._4.magic65		= htons(0x0600);
	req.packet._4.magic70		= htons(0x0600);
	req.packet._4.magic75		= htons(0x4300);
#endif

	if (send_msprequest(control, &packet->state.msproxy, &req) == -1)
		return -1;

	if (recv_mspresponse(control, &packet->state.msproxy, &res) == -1)
		return -1;

	if (res.serverid != packet->state.msproxy.serverid)
		serrx(EXIT_FAILURE, "expected res.serverid = 0x%x, is 0x%x",
		packet->state.msproxy.serverid, res.serverid);

	if (res.clientack != 0x01)
		serrx(EXIT_FAILURE, "expected res.clientack = 0x%x, is 0x%x",
		0x01, res.clientack);

	if (ntohs(res.command) >> 8 != 0x47)
		serrx(EXIT_FAILURE, "expected res.command = 47??, is 0x%x",
		ntohs(res.command));
#endif

	switch (packet->req.host.atype) {
		case SOCKS_ADDR_IPV4:
			/* LINTED pointer casts may be troublesome */
			sockshost2sockaddr(&packet->req.host, (struct sockaddr *)&addr);
			break;

		case SOCKS_ADDR_DOMAIN:
			slog(LOG_DEBUG, "%s: resolve packet", function);

			bzero(&req, sizeof(req));
			req.clientid	= packet->state.msproxy.clientid;
			req.serverid	= packet->state.msproxy.serverid;

			req.command	= htons(MSPROXY_RESOLVE);
			req.packet.resolve.hostlength
			= (unsigned char)(strlen(packet->req.host.addr.domain) + 1);
			memcpy(&req.packet.resolve.host, packet->req.host.addr.domain,
			(size_t)req.packet.resolve.hostlength);

			if (send_msprequest(control, &packet->state.msproxy, &req) == -1)
				return -1;

			if (recv_mspresponse(control, &packet->state.msproxy, &res) == -1)
				return -1;

			if (ntohs(res.command) != MSPROXY_RESOLVE_ACK)
				serrx(EXIT_FAILURE, "expected res.command = 0x%x, is 0x%x",
				MSPROXY_RESOLVE_ACK, ntohs(res.command));

			addr.sin_addr.s_addr = res.packet.resolve.hostaddr;
			slog(LOG_DEBUG, "%s: ip address of %s: %s",
			function, packet->req.host.addr.domain, inet_ntoa(addr.sin_addr));

			break;

		default:
			SERRX(packet->req.host.atype);
	}


	slog(LOG_DEBUG, "%s: packet #5", function);

	bzero(&req, sizeof(req));
	req.clientid	= packet->state.msproxy.clientid;
	req.serverid	= packet->state.msproxy.serverid;
	req.command		= htons(MSPROXY_CONNECT);
	req.packet._5.magic6		= htons(0x0200);
	req.packet._5.destport	= packet->req.host.port;
	req.packet._5.destaddr	= addr.sin_addr.s_addr;

	/*
	 * need to tell server what port we will connect from, so if socket
	 * is not bound, bind it.
	 */

	len = sizeof(addr);
	/* LINTED pointer casts may be troublesome */
	if (getsockname(s, (struct sockaddr *)&addr, &len) != 0)
		return -1;

	if (!ADDRISBOUND(addr)) {
		/*
		 * Don't have any specific preference for what address to bind and
		 * proxyserver only expects to be told port.
		 */

		addr.sin_addr.s_addr = htonl(INADDR_ANY);
		/* LINTED pointer casts may be troublesome */
		if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) != 0)
			return -1;

		len = sizeof(addr);
		/* LINTED pointer casts may be troublesome */
		if (getsockname(s, (struct sockaddr *)&addr, &len) != 0)
			return -1;
	}
	req.packet._5.srcport = addr.sin_port;

	if (send_msprequest(control, &packet->state.msproxy, &req) == -1)
		return -1;

	if (recv_mspresponse(control, &packet->state.msproxy, &res) == -1)
		return -1;

	if (ntohs(res.command) != MSPROXY_CONNECT_ACK) {
		swarnx("expected res.command = 0x%x, is 0x%x",
		MSPROXY_CONNECT_ACK, ntohs(res.command));
		packet->res.reply = MSPROXY_NOTALLOWED;
		return -1;
	}

	packet->res.host.atype					= SOCKS_ADDR_IPV4;
	packet->res.host.port					= res.packet._5.clientport;
	packet->res.host.addr.ipv4.s_addr	= res.packet._5.clientaddr;

	if (socks_connect(s, &packet->res.host) != 0) {
		swarn("%s: failed to connect to %s",
		function, sockshost2string(&packet->res.host, NULL, 0));
		return -1;
	}
	else
		slog(LOG_DEBUG, "%s: connected to %s",
		function, sockshost2string(&packet->res.host, NULL, 0));

	packet->res.host.atype					= SOCKS_ADDR_IPV4;
	packet->res.host.port					= res.packet._5.clientport;
	packet->res.host.addr.ipv4.s_addr	= res.packet._5.clientaddr;

	/* LINTED pointer casts may be troublesome */