/*

 * m_xt.c	xtables based targets

 *		utilities mostly ripped from iptables <duh, its the linux way>

 *

 *		This program is free software; you can distribute 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.

 *

 * Authors:  J Hadi Salim (hadi@cyberus.ca)

 */

/*XXX: in the future (xtables 1.4.3?) get rid of everything tagged

 * as TC_CONFIG_XT_H */

#include <sys/socket.h>

#include <netinet/in.h>

#include <arpa/inet.h>

#include <net/if.h>

#include <linux/netfilter.h>

#include <linux/netfilter_ipv4/ip_tables.h>

#include <xtables.h>

#include "utils.h"

#include "tc_util.h"

#include <linux/tc_act/tc_ipt.h>

#include <stdio.h>

#include <getopt.h>

#include <errno.h>

#include <string.h>

#include <netdb.h>

#include <stdlib.h>

#include <ctype.h>

#include <stdarg.h>

#include <limits.h>

#include <unistd.h>

#include <fcntl.h>

#include <sys/wait.h>

#ifdef TC_CONFIG_XT_H

#include "xt-internal.h"

#endif

#ifndef ALIGN

#define ALIGN(x, a)		__ALIGN_MASK(x, (typeof(x))(a)-1)

#define __ALIGN_MASK(x, mask)	(((x)+(mask))&~(mask))

#endif

static const char *pname = "tc-ipt";

static const char *tname = "mangle";

static const char *pversion = "0.2";

static const char *ipthooks[] = {

	"NF_IP_PRE_ROUTING",

	"NF_IP_LOCAL_IN",

	"NF_IP_FORWARD",

	"NF_IP_LOCAL_OUT",

	"NF_IP_POST_ROUTING",

};

static struct option original_opts[] = {

	{"jump", 1, 0, 'j'},

	{0, 0, 0, 0}

};

static struct option *opts = original_opts;

static unsigned int global_option_offset;

char *lib_dir;

const char *program_version = XTABLES_VERSION;

const char *program_name = "tc-ipt";

struct afinfo afinfo = {

	.family         = AF_INET,

	.libprefix      = "libxt_",

	.ipproto        = IPPROTO_IP,

	.kmod           = "ip_tables",

	.so_rev_target  = IPT_SO_GET_REVISION_TARGET,

};

#define OPTION_OFFSET 256

/*XXX: TC_CONFIG_XT_H */

static void free_opts(struct option *local_opts)

{

	if (local_opts != original_opts) {

		free(local_opts);

		opts = original_opts;

		global_option_offset = 0;

	}

}

/*XXX: TC_CONFIG_XT_H */

static struct option *

merge_options(struct option *oldopts, const struct option *newopts,

	      unsigned int *option_offset)

{

	struct option *merge;

	unsigned int num_old, num_new, i;

	for (num_old = 0; oldopts[num_old].name; num_old++);

	for (num_new = 0; newopts[num_new].name; num_new++);

	*option_offset = global_option_offset + OPTION_OFFSET;

	merge = malloc(sizeof(struct option) * (num_new + num_old + 1));

	memcpy(merge, oldopts, num_old * sizeof(struct option));

	for (i = 0; i < num_new; i++) {

		merge[num_old + i] = newopts[i];

		merge[num_old + i].val += *option_offset;

	}

	memset(merge + num_old + num_new, 0, sizeof(struct option));

	return merge;

}

/*XXX: TC_CONFIG_XT_H */

#ifndef TRUE

#define TRUE 1

#endif

#ifndef FALSE

#define FALSE 0

#endif

/*XXX: TC_CONFIG_XT_H */

int

check_inverse(const char option[], int *invert, int *my_optind, int argc)

{

	if (option && strcmp(option, "!") == 0) {

		if (*invert)

			exit_error(PARAMETER_PROBLEM,

				   "Multiple `!' flags not allowed");

		*invert = TRUE;

		if (my_optind != NULL) {

			++*my_optind;

			if (argc && *my_optind > argc)

				exit_error(PARAMETER_PROBLEM,

					   "no argument following `!'");

		}

		return TRUE;

	}

	return FALSE;

}

/*XXX: TC_CONFIG_XT_H */

void exit_error(enum exittype status, const char *msg, ...)

{

	va_list args;

	va_start(args, msg);

	fprintf(stderr, "%s v%s: ", pname, pversion);

	vfprintf(stderr, msg, args);

	va_end(args);

	fprintf(stderr, "\n");

	/* On error paths, make sure that we don't leak memory */

	exit(status);

}

/*XXX: TC_CONFIG_XT_H */

static void set_revision(char *name, u_int8_t revision)

{

	/* Old kernel sources don't have ".revision" field,

	*  but we stole a byte from name. */

	name[IPT_FUNCTION_MAXNAMELEN - 2] = '\0';

	name[IPT_FUNCTION_MAXNAMELEN - 1] = revision;

}

/*

 * we may need to check for version mismatch

*/

int

build_st(struct xtables_target *target, struct xt_entry_target *t)

{

	size_t size =

		    XT_ALIGN(sizeof(struct xt_entry_target)) + target->size;

	if (t == NULL) {

		target->t = fw_calloc(1, size);

		target->t->u.target_size = size;

		strcpy(target->t->u.user.name, target->name);

		set_revision(target->t->u.user.name, target->revision);

		if (target->init != NULL)

			target->init(target->t);

	} else {

		target->t = t;

	}

	return 0;

}

inline void set_lib_dir(void)

{

	lib_dir = getenv("XTABLES_LIBDIR");

	if (!lib_dir) {

		lib_dir = getenv("IPTABLES_LIB_DIR");

		if (lib_dir)

			fprintf(stderr, "using deprecated IPTABLES_LIB_DIR\n");

	}

	if (lib_dir == NULL)

		lib_dir = XT_LIB_DIR;

}

static int parse_ipt(struct action_util *a, int *argc_p,

		     char ***argv_p, int tca_id, struct nlmsghdr *n)

{

	struct xtables_target *m = NULL;

	struct ipt_entry fw;

	struct rtattr *tail;

	int c;

	int rargc = *argc_p;

	char **argv = *argv_p;

	int argc = 0, iargc = 0;

	char k[FILTER_NAMESZ];

	int size = 0;

	int iok = 0, ok = 0;

	__u32 hook = 0, index = 0;

	set_lib_dir();

	{

		int i;

		for (i = 0; i < rargc; i++) {

			if (!argv[i] || strcmp(argv[i], "action") == 0)

				break;

		}

		iargc = argc = i;

	}

	if (argc <= 2) {

		fprintf(stderr, "bad arguments to ipt %d vs %d\n", argc, rargc);

		return -1;

	}

	while (1) {

		c = getopt_long(argc, argv, "j:", opts, NULL);

		if (c == -1)

			break;

		switch (c) {

		case 'j':

			m = find_target(optarg, TRY_LOAD);

			if (m != NULL) {

				if (build_st(m, NULL) < 0) {

					printf(" %s error\n", m->name);

					return -1;

				}

				opts =

				    merge_options(opts, m->extra_opts,

						  &m->option_offset);

			} else {

				fprintf(stderr, " failed to find target %s\n\n", optarg);

				return -1;

			}

			ok++;

			break;

		default:

			memset(&fw, 0, sizeof(fw));

			if (m) {

				m->parse(c - m->option_offset, argv, 0,

					 &m->tflags, NULL, &m->t);

			} else {

				fprintf(stderr, " failed to find target %s\n\n", optarg);

				return -1;

			}

			ok++;

			break;

		}

	}

	if (iargc > optind) {

		if (matches(argv[optind], "index") == 0) {

			if (get_u32(&index, argv[optind + 1], 10)) {

				fprintf(stderr, "Illegal \"index\"\n");

				free_opts(opts);

				return -1;

			}

			iok++;

			optind += 2;

		}

	}

	if (!ok && !iok) {

		fprintf(stderr, " ipt Parser BAD!! (%s)\n", *argv);

		return -1;

	}

	/* check that we passed the correct parameters to the target */

	if (m)

		m->final_check(m->tflags);

	{

		struct tcmsg *t = NLMSG_DATA(n);

		if (t->tcm_parent != TC_H_ROOT

		    && t->tcm_parent == TC_H_MAJ(TC_H_INGRESS)) {

			hook = NF_IP_PRE_ROUTING;

		} else {

			hook = NF_IP_POST_ROUTING;

		}

	}

	tail = addattr_nest(n, MAX_MSG, tca_id);

	fprintf(stdout, "tablename: %s hook: %s\n ", tname, ipthooks[hook]);

	fprintf(stdout, "\ttarget: ");

	if (m)

		m->print(NULL, m->t, 0);

	fprintf(stdout, " index %d\n", index);

	if (strlen(tname) > 16) {

		size = 16;

		k[15] = 0;

	} else {

		size = 1 + strlen(tname);

	}

	strncpy(k, tname, size);

	addattr_l(n, MAX_MSG, TCA_IPT_TABLE, k, size);

	addattr_l(n, MAX_MSG, TCA_IPT_HOOK, &hook, 4);

	addattr_l(n, MAX_MSG, TCA_IPT_INDEX, &index, 4);

	if (m)

		addattr_l(n, MAX_MSG, TCA_IPT_TARG, m->t, m->t->u.target_size);

	addattr_nest_end(n, tail);

	argc -= optind;

	argv += optind;

	*argc_p = rargc - iargc;

	*argv_p = argv;

	optind = 0;

	free_opts(opts);

	/* Clear flags if target will be used again */

        m->tflags = 0;

        m->used = 0;

	/* Free allocated memory */

	if (m->t)

	    free(m->t);

	return 0;

}

static int

print_ipt(struct action_util *au, FILE * f, struct rtattr *arg)

{

	struct rtattr *tb[TCA_IPT_MAX + 1];

	struct xt_entry_target *t = NULL;

	struct xtables_target *m;

	__u32 hook;

	if (arg == NULL)

		return -1;

	set_lib_dir();

	parse_rtattr_nested(tb, TCA_IPT_MAX, arg);

	if (tb[TCA_IPT_TABLE] == NULL) {

		fprintf(stderr, "Missing ipt table name, assuming mangle\n");

	} else {

		fprintf(f, "tablename: %s ",

			rta_getattr_str(tb[TCA_IPT_TABLE]));

	}

	if (tb[TCA_IPT_HOOK] == NULL) {

		fprintf(stderr, "Missing ipt hook name\n");

		return -1;

	}

	if (tb[TCA_IPT_TARG] == NULL) {

		fprintf(stderr, "Missing ipt target parameters\n");

		return -1;

	}

	hook = rta_getattr_u32(tb[TCA_IPT_HOOK]);

	fprintf(f, " hook: %s\n", ipthooks[hook]);

	t = RTA_DATA(tb[TCA_IPT_TARG]);

	m = find_target(t->u.user.name, TRY_LOAD);

	if (m != NULL) {

		if (build_st(m, t) < 0) {

			fprintf(stderr, " %s error\n", m->name);

			return -1;

		}

		opts =

			merge_options(opts, m->extra_opts,

				      &m->option_offset);

	} else {

		fprintf(stderr, " failed to find target %s\n\n",

			t->u.user.name);

		return -1;

	}

	fprintf(f, "\ttarget ");

	m->print(NULL, m->t, 0);

	if (tb[TCA_IPT_INDEX] == NULL) {

		fprintf(f, " [NULL ipt target index ]\n");

	} else {

		__u32 index;

		index = rta_getattr_u32(tb[TCA_IPT_INDEX]);

		fprintf(f, "\n\tindex %u", index);

	}

	if (tb[TCA_IPT_CNT]) {

		struct tc_cnt *c  = RTA_DATA(tb[TCA_IPT_CNT]);

		fprintf(f, " ref %d bind %d", c->refcnt, c->bindcnt);

	}

	if (show_stats) {

		if (tb[TCA_IPT_TM]) {

			struct tcf_t *tm = RTA_DATA(tb[TCA_IPT_TM]);

			print_tm(f, tm);

		}

	}

	fprintf(f, "\n");

	free_opts(opts);

	return 0;

}

struct action_util ipt_action_util = {

	.id = "ipt",

	.parse_aopt = parse_ipt,

	.print_aopt = print_ipt,

};