Add new (iptables 1.4.5 compatible) tc/ipt/xt module.

Add a new cleaned up m_xt.c based on m_xt_old.c
The new m_xt.c has been updated to use the new names and new api
that xtables exposes in iptables 1.4.5.
All the old internal api cruft has also been dropped.

Additionally, a configure script test is added to check for
the new xtables api and set the TC_CONFIG_XT flag in Config.
(tc/Makefile already handles this flag in previous commit.)
Signed-off-by: Andreas Henriksson <andreas@fatal.se>

configure

@@ -28,6 +28,33 @@ rm -f /tmp/atmtest.c /tmp/atmtest
 
 echo -n " IPT	"
 
+#check if we have xtables from iptables >= 1.4.5.
+cat >/tmp/ipttest.c <<EOF
+#include <xtables.h>
+#include <linux/netfilter.h>
+static struct xtables_globals test_globals = {
+	.option_offset = 0,
+	.program_name = "tc-ipt",
+	.program_version = XTABLES_VERSION,
+	.orig_opts = NULL,
+	.opts = NULL,
+	.exit_err = NULL,
+};
+
+int main(int argc, char **argv)
+{
+	xtables_init_all(&test_globals, NFPROTO_IPV4);
+	return 0;
+}
+
+EOF
+
+if gcc -I$INCLUDE $IPTC -o /tmp/ipttest /tmp/ipttest.c $IPTL -ldl -lxtables >/dev/null 2>&1
+then
+	echo "TC_CONFIG_XT:=y" >>Config
+	echo "using xtables instead of iptables"
+fi
+
 #check if we need dont our internal header ..
 cat >/tmp/ipttest.c <<EOF
 #include <xtables.h>

tc/m_xt.c

+/*
+ * 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)
+ */
+
+#include <syslog.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <net/if.h>
+#include <limits.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 <dlfcn.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>
+#ifndef XT_LIB_DIR
+#       define XT_LIB_DIR "/lib/xtables"
+#endif
+
+static const char *tname = "mangle";
+
+char *lib_dir;
+
+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[] = {
+	{
+		.name = "jump",
+		.has_arg = 1,
+		.val = 'j'
+	},
+	{0, 0, 0, 0}
+};
+
+static struct xtables_globals tcipt_globals = {
+	.option_offset = 0,
+	.program_name = "tc-ipt",
+	.program_version = "0.2",
+	.orig_opts = original_opts,
+	.opts = original_opts,
+	.exit_err = NULL,
+};
+
+/*
+ * 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 (NULL == t) {
+		target->t = xtables_calloc(1, size);
+		target->t->u.target_size = size;
+		strcpy(target->t->u.user.name, target->name);
+		xtables_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[16];
+	int res = -1;
+	int size = 0;
+	int iok = 0, ok = 0;
+	__u32 hook = 0, index = 0;
+	res = 0;
+
+	xtables_init_all(&tcipt_globals, NFPROTO_IPV4);
+	set_lib_dir();
+
+	{
+		int i;
+		for (i = 0; i < rargc; i++) {
+			if (NULL == argv[i] || 0 == strcmp(argv[i], "action")) {
+				break;
+			}
+		}
+		iargc = argc = i;
+	}
+
+	if (argc <= 2) {
+		fprintf(stderr,"bad arguements to ipt %d vs %d \n", argc, rargc);
+		return -1;
+	}
+
+	while (1) {
+		c = getopt_long(argc, argv, "j:", tcipt_globals.opts, NULL);
+		if (c == -1)
+			break;
+		switch (c) {
+		case 'j':
+			m = xtables_find_target(optarg, XTF_TRY_LOAD);
+			if (NULL != m) {
+
+				if (0 > build_st(m, NULL)) {
+					printf(" %s error \n", m->name);
+					return -1;
+				}
+				tcipt_globals.opts =
+				    xtables_merge_options(tcipt_globals.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");
+				xtables_free_opts(1);
+				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->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 = NLMSG_TAIL(n);
+	addattr_l(n, MAX_MSG, tca_id, NULL, 0);
+	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);
+	tail->rta_len = (void *) NLMSG_TAIL(n) - (void *) tail;
+
+	argc -= optind;
+	argv += optind;
+	*argc_p = rargc - iargc;
+	*argv_p = argv;
+
+	optind = 0;
+	xtables_free_opts(1);
+	/* 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;
+
+	if (arg == NULL)
+		return -1;
+
+	xtables_init_all(&tcipt_globals, NFPROTO_IPV4);
+	set_lib_dir();
+
+	parse_rtattr_nested(tb, TCA_IPT_MAX, arg);
+
+	if (tb[TCA_IPT_TABLE] == NULL) {
+		fprintf(f, "[NULL ipt table name ] assuming mangle ");
+	} else {
+		fprintf(f, "tablename: %s ",
+			(char *) RTA_DATA(tb[TCA_IPT_TABLE]));
+	}
+
+	if (tb[TCA_IPT_HOOK] == NULL) {
+		fprintf(f, "[NULL ipt hook name ]\n ");
+		return -1;
+	} else {
+		__u32 hook;
+		hook = *(__u32 *) RTA_DATA(tb[TCA_IPT_HOOK]);
+		fprintf(f, " hook: %s \n", ipthooks[hook]);
+	}
+
+	if (tb[TCA_IPT_TARG] == NULL) {
+		fprintf(f, "\t[NULL ipt target parameters ] \n");
+		return -1;
+	} else {
+		struct xtables_target *m = NULL;
+		t = RTA_DATA(tb[TCA_IPT_TARG]);
+		m = xtables_find_target(t->u.user.name, XTF_TRY_LOAD);
+		if (NULL != m) {
+			if (0 > build_st(m, t)) {
+				fprintf(stderr, " %s error \n", m->name);
+				return -1;
+			}
+
+			tcipt_globals.opts =
+			    xtables_merge_options(tcipt_globals.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 = *(__u32 *) RTA_DATA(tb[TCA_IPT_INDEX]);
+			fprintf(f, " \n\tindex %d", 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");
+
+	}
+	xtables_free_opts(1);
+
+	return 0;
+}
+
+struct action_util ipt_action_util = {
+        .id = "ipt",
+        .parse_aopt = parse_ipt,
+        .print_aopt = print_ipt,
+};
+