/* hlfl
 * Copyright © 2000-2003 Renaud Deraison
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#include "includes.h"
#include "hlfl.h"

extern int icmp(char *);
extern int matched_if;
extern translator_t active_translator;

static FILE *fout;

static char *icmp_types(type)
char *type;
{
	char *ret = malloc(20);
	memset(ret, 0, 20);
	if (!strlen(type))
		return ret;
	if (!strcmp(type, "echo-reply"))
		sprintf(ret, "icmptypes 0");
	else if (!strcmp(type, "destination-unreachable"))
		sprintf(ret, "icmptypes 3");
	else if (!strcmp(type, "echo-request"))
		sprintf(ret, "icmptypes 8");
	else if (!strcmp(type, "time-exceeded"))
		sprintf(ret, "icmptypes 11");
	else
		fprintf(stderr, "Warning. Unknown icmp type '%s'\n", type);
	return ret;
}

/*------------------------------------------------------------------
 * BSD's ipfw
 *------------------------------------------------------------------*/
int translate_bsd_ipfw(op, proto, src, log, dst, sports, dports, interface)
int op;
char *proto;
char *src;
char *dst;
int log;
char *sports;
char *dports;
char *interface;
{
	char *via = strdup("");
	char *icmp_code = "";
	char *logit = "";

	if (log)
		logit = " log";

	if (icmp(proto)) {
		if (sports && strlen(sports))
			icmp_code = icmp_types(sports);
		else if (dports && strlen(dports))
			icmp_code = icmp_types(dports);
		else
			icmp_code = icmp_types("");

		sports = "";
		dports = "";
	}

	if (!sports)
		sports = "";
	if (!dports)
		dports = "";

	if (interface) {
		free(via);
		via = malloc(10 + strlen(interface));
		sprintf(via, "via %s", interface);
	}
	switch (op) {
	case ACCEPT_ONE_WAY:
		fprintf(fout,
			"$ipfw -f add allow%s %s from %s %s to %s %s out %s %s\n",
			logit, proto, src, sports, dst, dports, icmp_code, via);
		break;
	case ACCEPT_ONE_WAY_REVERSE:
		fprintf(fout,
			"$ipfw -f add allow%s %s from %s %s to %s %s in %s %s\n",
			logit, proto, dst, dports, src, sports, icmp_code, via);
		break;
	case ACCEPT_TWO_WAYS:
		fprintf(fout,
			"$ipfw -f add allow%s %s from %s %s to %s %s out %s %s\n",
			logit, proto, src, sports, dst, dports, icmp_code, via);
		fprintf(fout,
			"$ipfw -f add allow%s %s from %s %s to %s %s in %s %s\n",
			logit, proto, dst, dports, src, sports, icmp_code, via);
		break;
	case ACCEPT_TWO_WAYS_ESTABLISHED:
		if (!strcmp(proto, "tcp")) {
			fprintf(fout,
				"$ipfw -f add allow%s %s from %s %s to %s %s out %s\n",
				logit, proto, src, sports, dst, dports, via);
			fprintf(fout,
				"$ipfw -f add deny%s %s from %s %s to %s %s in setup %s\n",
				logit, proto, dst, dports, src, sports, via);
			fprintf(fout,
				"$ipfw -f add accept%s %s from %s %s to %s %s in %s\n",
				logit, proto, dst, dports, src, sports, via);
		} else {
			if (active_translator == TRANSLATOR_IPFW4) {
				fprintf(fout,
					"$ipfw -f add allow%s %s from %s %s to %s %s out %s %s keep-state\n",
					logit, proto, src, sports, dst,
					dports, icmp_code, via);
				fprintf(fout,
					"$ipfw -f add allow%s %s from %s %s to %s %s in %s %s keep-state\n",
					logit, proto, dst, dports, src,
					sports, icmp_code, via);
			} else {
				/* XXX stateful needed here */
				fprintf(fout,
					"# (warning. A stateful firewall would be better here); you could use ipfw4.\n");
				fprintf(fout,
					"$ipfw -f add allow%s %s from %s %s to %s %s out %s %s\n",
					logit, proto, src, sports, dst,
					dports, icmp_code, via);
				fprintf(fout,
					"$ipfw -f add allow%s %s from %s %s to %s %s in %s %s\n",
					logit, proto, dst, dports, src,
					sports, icmp_code, via);
			}
		}
		break;

	case ACCEPT_TWO_WAYS_ESTABLISHED_REVERSE:
		if (!strcmp(proto, "tcp")) {
			fprintf(fout,
				"$ipfw -f add allow%s %s from %s %s to %s %s in %s\n",
				logit, proto, dst, dports, src, sports, via);
			fprintf(fout,
				"$ipfw -f add deny%s %s from %s %s to %s %s out setup %s\n",
				logit, proto, src, sports, dst, dports, via);
			fprintf(fout,
				"$ipfw -f add accept%s %s from %s %s to %s %s out %s\n",
				logit, proto, src, sports, dst, dports, via);
		} else {
			/* XXX stateful needed here */
			fprintf(fout,
				"# (warning. A stateful firewall would be better here)\n");
			fprintf(fout,
				"$ipfw -f add allow%s %s from %s %s to %s %s in %s %s\n",
				logit, proto, dst, dports, src, sports, icmp_code, via);
			fprintf(fout,
				"$ipfw -f add allow%s %s from %s %s to %s %s out %s %s\n",
				logit, proto, src, sports, dst, dports, icmp_code, via);
		}
		break;
	case DENY_ALL:
		fprintf(fout,
			"$ipfw -f add deny%s %s from %s %s to %s %s out %s %s\n",
			logit, proto, src, sports, dst, dports, icmp_code, via);
		fprintf(fout,
			"$ipfw -f add deny%s %s from %s %s to %s %s in %s %s\n",
			logit, proto, dst, dports, src, sports, icmp_code, via);
		break;
	case REJECT_ALL:
		/* Add an additional rule to correctly reject tcp when rejecting all */
		if (!strcmp(proto, "all")) {
			fprintf(fout,
				"$ipfw -f add reset%s tcp from %s %s to %s %s out %s %s\n",
				logit, src, sports, dst, dports, icmp_code, via);
			fprintf(fout,
				"$ipfw -f add reset%s tcp from %s %s to %s %s in %s %s\n",
				logit, dst, dports, src, sports, icmp_code, via);
		}
		/* Correctly reject tcp */
		if (!strcmp(proto, "tcp")) {
			fprintf(fout,
				"$ipfw -f add reset%s %s from %s %s to %s %s out %s %s\n",
				logit, proto, src, sports, dst, dports, icmp_code, via);
			fprintf(fout,
				"$ipfw -f add reset%s %s from %s %s to %s %s in %s %s\n",
				logit, proto, dst, dports, src, sports, icmp_code, via);
		} else {
			fprintf(fout,
				"$ipfw -f add reject%s %s from %s %s to %s %s out %s %s\n",
				logit, proto, src, sports, dst, dports, icmp_code, via);
			fprintf(fout,
				"$ipfw -f add reject%s %s from %s %s to %s %s in %s %s\n",
				logit, proto, dst, dports, src, sports, icmp_code, via);
		}
		break;
	case DENY_OUT:
		fprintf(fout,
			"$ipfw -f add deny%s %s from %s %s to %s %s out %s %s\n",
			logit, proto, src, sports, dst, dports, icmp_code, via);
		break;
	case DENY_IN:
		fprintf(fout,
			"$ipfw -f add deny%s %s from %s %s to %s %s in %s %s\n",
			logit, proto, dst, dports, src, sports, icmp_code, via);
		break;
	case REJECT_OUT:
		/* Add an additional rule to correctly reject tcp when rejecting all */
		if (!strcmp(proto, "all")) {
			fprintf(fout,
				"$ipfw -f add reset%s tcp from %s %s to %s %s out %s %s\n",
				logit, src, sports, dst, dports, icmp_code, via);
		}
		/* Correctly reject tcp */
		if (!strcmp(proto, "tcp")) {
			fprintf(fout,
				"$ipfw -f add reset%s %s from %s %s to %s %s out %s %s\n",
				logit, proto, src, sports, dst, dports, icmp_code, via);
		} else {
			fprintf(fout,
				"$ipfw -f add reject%s %s from %s %s to %s %s out %s %s\n",
				logit, proto, src, sports, dst, dports, icmp_code, via);
		}
		break;
	case REJECT_IN:
		/* Add an additional rule to correctly reject tcp when rejecting all */
		if (!strcmp(proto, "all")) {
			fprintf(fout,
				"$ipfw -f add reset%s tcp from %s %s to %s %s in %s %s\n",
				logit, dst, dports, src, sports, icmp_code, via);
		}
		/* Correctly reject tcp */
		if (!strcmp(proto, "tcp")) {
			fprintf(fout,
				"$ipfw -f add reset%s %s from %s %s to %s %s in %s %s\n",
				logit, proto, dst, dports, src, sports, icmp_code, via);
		} else {
			fprintf(fout,
				"$ipfw -f add reject%s %s from %s %s to %s %s in %s %s\n",
				logit, proto, dst, dports, src, sports, icmp_code, via);
		}
		break;
	}
	free(via);
	if (icmp(proto)) {
		free(icmp_code);
	}
	return 0;
}

int translate_bsd_ipfw_start(FILE * output_file)
{
	fout = output_file;

	fprintf(fout, "#!/bin/sh\n#\n");
	fprintf(fout, "# Firewall rules generated by hlfl\n\n");

	fprintf(fout, "ipfw=\"/sbin/ipfw -q\"\n\n");
	fprintf(fout, "$ipfw -f flush\n\n");

	fprintf(fout, "$ipfw -f add check-state\n\n");

	return 0;
}

void print_comment_ipfw(buffer)
char *buffer;
{
	fprintf(fout, "#%s", buffer);
}

void include_text_ipfw(c)
char *c;
{
	if (!strncmp("if(", c, 3)) {
		if (!strncmp("if(ipfw)", c, strlen("if(ipfw)"))) {
			matched_if = 1;
			fprintf(fout, "%s", c + strlen("if(ipfw)"));
		} else
			matched_if = 0;
	} else
		fprintf(fout, "%s", c);
}