initial import

This tree contains the tests for conntrackd's user-space helper
infrastructure. They use to live in the conntrack-tools tree.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

21 files changed, 1983 insertions, 0 deletions

diff --git a/Make_global.am b/Make_global.am
new file mode 100644
index 0000000..06785a1
--- /dev/null
+++ b/Make_global.am
@@ -0,0 +1,7 @@
+AM_CPPFLAGS = -I$(top_srcdir)/include -I../../../include
+
+AM_CFLAGS = -std=gnu99 -W -Wall \
+	-Wmissing-prototypes -Wwrite-strings -Wcast-qual -Wfloat-equal -Wshadow -Wpointer-arith -Wbad-function-cast -Wsign-compare -Waggregate-return -Wmissing-declarations -Wredundant-decls -Wnested-externs -Winline -Wstrict-prototypes -Wundef \
+	-Wno-unused-parameter \
+	${LIBNETFILTER_CONNTRACK_CFLAGS} \
+	${LIBNETFILTER_CTTIMEOUT_CFLAGS}
diff --git a/Makefile.am b/Makefile.am
new file mode 100644
index 0000000..326e525
--- /dev/null
+++ b/Makefile.am
@@ -0,0 +1,20 @@
+include $(top_srcdir)/Make_global.am
+
+check_PROGRAMS = cthelper-test
+
+cthelper_test_SOURCES = proto.c			\
+			ct.c			\
+			l3_ipv4.c		\
+			l4_tcp.c		\
+			l4_udp.c		\
+			expect.c		\
+			helpers.c		\
+			main.c
+
+cthelper_test_LDFLAGS = -dynamic 		\
+			-lpcap			\
+			-ldl			\
+			-lmnl			\
+			-lnetfilter_queue	\
+			-lnetfilter_conntrack	\
+			-export-dynamic
diff --git a/README b/README
new file mode 100644
index 0000000..79e53f3
--- /dev/null
+++ b/README
@@ -0,0 +1,17 @@
+Author: Pablo Neira Ayuso <pablo@netfilter.org>
+Date: 06/May/2013
+
+= conntrackd's helper tests =
+
+This tree contains tests for the user-space helper infrastructure that
+conntrackd provides.
+
+You can compile it via:
+
+	autoreconf -fi
+	./configure
+	make check
+
+You can run the tests by invoking the run-test.sh script in this tree.
+
+-EOF-
diff --git a/configure.ac b/configure.ac
new file mode 100644
index 0000000..8b3da5c
--- /dev/null
+++ b/configure.ac
@@ -0,0 +1,64 @@
+AC_INIT(cthelper-test, 0.0.1, pablo@netfilter.org)
+AC_CONFIG_AUX_DIR([build-aux])
+
+AC_CANONICAL_HOST
+AC_CONFIG_MACRO_DIR([m4])
+AM_INIT_AUTOMAKE([-Wall foreign subdir-objects
+	tar-pax no-dist-gzip dist-bzip2 1.6])
+
+dnl kernel style compile messages
+m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
+
+AC_SEARCH_LIBS([dlopen], [dl], [libdl_LIBS="$LIBS"; LIBS=""])
+AC_SUBST([libdl_LIBS])
+
+AC_PROG_CC
+AC_DISABLE_STATIC
+AM_PROG_LIBTOOL
+AC_PROG_INSTALL
+AC_PROG_LN_S
+AM_PROG_LEX
+AC_PROG_YACC
+
+case "$host" in
+*-*-linux*) ;;
+*) AC_MSG_ERROR([Linux only, dude!]);;
+esac
+
+PKG_CHECK_MODULES([LIBNETFILTER_CONNTRACK], [libnetfilter_conntrack >= 1.0.0])
+PKG_CHECK_MODULES([LIBNETFILTER_QUEUE], [libnetfilter_queue >= 1.0.0])
+
+AC_CHECK_HEADERS(arpa/inet.h)
+dnl check for inet_pton
+AC_CHECK_FUNCS(inet_pton)
+dnl Some systems have it, but not IPv6
+if test "$ac_cv_func_inet_pton" = "yes" ; then
+AC_MSG_CHECKING(if inet_pton supports IPv6)
+AC_RUN_IFELSE([AC_LANG_SOURCE([[
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_SOCKET_H
+#include <sys/socket.h>
+#endif
+#ifdef HAVE_NETINET_IN_H
+#include <netinet/in.h>
+#endif
+#ifdef HAVE_ARPA_INET_H
+#include <arpa/inet.h>
+#endif
+int main()
+  {
+     struct in6_addr addr6;
+     if (inet_pton(AF_INET6, "::1", &addr6) < 1)
+        exit(1);
+     else
+        exit(0);
+  }
+  ]])],[ AC_MSG_RESULT(yes)
+       AC_DEFINE_UNQUOTED(HAVE_INET_PTON_IPV6, 1, [Define to 1 if inet_pton supports IPv6.])
+  ],[AC_MSG_RESULT(no)],[AC_MSG_RESULT(no)])
+fi
+
+AC_CONFIG_FILES([Makefile])
+AC_OUTPUT
diff --git a/ct.c b/ct.c
new file mode 100755
index 0000000..1c17336
--- /dev/null
+++ b/ct.c
@@ -0,0 +1,91 @@
+#include <stdlib.h>
+#include <netinet/ip.h>
+#include <netinet/tcp.h>
+
+#include <linux/if_ether.h>
+
+#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
+
+#include "proto.h"
+#include "helper.h"
+#include "myct.h"
+#include "ct.h"
+
+static LIST_HEAD(ct_list);
+
+struct nf_ct_entry *
+ct_alloc(const uint8_t *pkt, unsigned int l3hdr_len,
+	 struct cthelper_proto_l2l3_helper *l3h,
+	 struct cthelper_proto_l4_helper *l4h)
+{
+	struct nf_ct_entry *ct;
+
+	ct = calloc(1, sizeof(struct nf_ct_entry));
+	if (ct == NULL)
+		return NULL;
+
+	ct->myct = calloc(1, sizeof(struct myct));
+	if (ct->myct == NULL) {
+		free(ct);
+		return NULL;
+	}
+	ct->myct->ct = nfct_new();
+	if (ct->myct->ct == NULL) {
+		free(ct->myct);
+		free(ct);
+		return NULL;
+	}
+	/* FIXME: use good private helper size */
+	ct->myct->priv_data = calloc(1, 128);
+	if (ct->myct->priv_data == NULL) {
+		nfct_destroy(ct->myct->ct);
+		free(ct->myct);
+		free(ct);
+		return NULL;
+	}
+
+	l3h->l3ct_build(pkt, ct->myct->ct);
+	l4h->l4ct_build(pkt + l3hdr_len, ct->myct->ct);
+
+	return ct;
+}
+
+struct nf_ct_entry *
+ct_find(const uint8_t *pkt, unsigned int l3hdr_len,
+	struct cthelper_proto_l2l3_helper *l3h,
+	struct cthelper_proto_l4_helper *l4h, unsigned int *ctinfo)
+{
+	struct nf_ct_entry *cur;
+
+	list_for_each_entry(cur, &ct_list, head) {
+		if (l3h->l3ct_cmp_orig(pkt, cur->myct->ct) &&
+		    l4h->l4ct_cmp_orig(pkt + l3hdr_len, cur->myct->ct)) {
+			*ctinfo = 0;
+			return cur;
+		}
+		if (l3h->l3ct_cmp_repl(pkt, cur->myct->ct) &&
+		     l4h->l4ct_cmp_repl(pkt + l3hdr_len, cur->myct->ct)) {
+			*ctinfo = IP_CT_IS_REPLY;
+			return cur;
+		}
+	}
+	return NULL;
+}
+
+void ct_add(struct nf_ct_entry *ct)
+{
+	list_add(&ct->head, &ct_list);
+}
+
+void ct_flush(void)
+{
+	struct nf_ct_entry *cur, *tmp;
+
+	list_for_each_entry_safe(cur, tmp, &ct_list, head) {
+		list_del(&cur->head);
+		free(cur->myct->priv_data);
+		free(cur->myct->ct);
+		free(cur->myct);
+		free(cur);
+	}
+}
diff --git a/ct.h b/ct.h
new file mode 100755
index 0000000..9639218
--- /dev/null
+++ b/ct.h
@@ -0,0 +1,22 @@
+#ifndef _CT_H_
+#define _CT_H_
+
+#include "include/linux_list.h"
+#include "include/myct.h"
+
+struct nf_ct_entry {
+	struct list_head	head;
+	struct myct		*myct;
+};
+
+struct cthelper_proto_l2l3_helper;
+struct cthelper_proto_l4_helper;
+
+struct nf_ct_entry *ct_alloc(const uint8_t *pkt, unsigned int l3hdr_len, struct cthelper_proto_l2l3_helper *l3h, struct cthelper_proto_l4_helper *l4h);
+
+struct nf_ct_entry *ct_find(const uint8_t *pkt, unsigned int l3hdr_len, struct cthelper_proto_l2l3_helper *l3h, struct cthelper_proto_l4_helper *l4h, unsigned int *ctinfo);
+
+void ct_add(struct nf_ct_entry *ct);
+void ct_flush(void);
+
+#endif
diff --git a/expect.c b/expect.c
new file mode 100644
index 0000000..7a1fe9a
--- /dev/null
+++ b/expect.c
@@ -0,0 +1,200 @@
+/*
+ * (C) 2012 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 version 2 as
+ * published by the Free Software Foundation (or any later at your option).
+ *
+ * This code has been sponsored by Vyatta Inc. <http://www.vyatta.com>
+ */
+
+#include "include/helper.h"
+#include "test.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <limits.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dlfcn.h>
+
+int
+cthelper_expect_init(struct nf_expect *exp, struct nf_conntrack *master,
+		  uint32_t class,
+		  union nfct_attr_grp_addr *saddr,
+		  union nfct_attr_grp_addr *daddr,
+		  uint8_t l4proto, uint16_t *sport, uint16_t *dport,
+		  uint32_t flags)
+{
+	struct nf_conntrack *expected, *mask;
+
+	expected = nfct_new();
+	if (!expected)
+		return -1;
+
+	mask = nfct_new();
+	if (!mask)
+		return -1;
+
+	if (saddr) {
+		switch(nfct_get_attr_u8(master, ATTR_L3PROTO)) {
+		int i;
+		uint32_t addr[4] = {};
+
+		case AF_INET:
+			nfct_set_attr_u8(expected, ATTR_L3PROTO, AF_INET);
+			nfct_set_attr_u32(expected, ATTR_IPV4_SRC, saddr->ip);
+
+			nfct_set_attr_u8(mask, ATTR_L3PROTO, AF_INET);
+			nfct_set_attr_u32(mask, ATTR_IPV4_SRC, 0xffffffff);
+			break;
+		case AF_INET6:
+			nfct_set_attr_u8(expected, ATTR_L3PROTO, AF_INET6);
+			nfct_set_attr(expected, ATTR_IPV6_SRC, saddr->ip6);
+
+			for (i=0; i<4; i++)
+				memset(addr, 0xffffffff, sizeof(uint32_t));
+
+			nfct_set_attr_u8(mask, ATTR_L3PROTO, AF_INET6);
+			nfct_set_attr(mask, ATTR_IPV6_SRC, addr);
+			break;
+		default:
+			break;
+		}
+	} else {
+		switch(nfct_get_attr_u8(master, ATTR_L3PROTO)) {
+		int i;
+		uint32_t addr[4] = {};
+
+		case AF_INET:
+			nfct_set_attr_u8(expected, ATTR_L3PROTO, AF_INET);
+			nfct_set_attr_u32(expected, ATTR_IPV4_SRC, 0x00000000);
+
+			nfct_set_attr_u8(mask, ATTR_L3PROTO, AF_INET);
+			nfct_set_attr_u32(mask, ATTR_IPV4_SRC, 0x00000000);
+			break;
+		case AF_INET6:
+			for (i=0; i<4; i++)
+				memset(addr, 0x00000000, sizeof(uint32_t));
+
+			nfct_set_attr_u8(expected, ATTR_L3PROTO, AF_INET6);
+			nfct_set_attr(expected, ATTR_IPV6_SRC, addr);
+
+			nfct_set_attr_u8(mask, ATTR_L3PROTO, AF_INET6);
+			nfct_set_attr(mask, ATTR_IPV6_SRC, addr);
+			break;
+		default:
+			break;
+		}
+	}
+
+	if (sport) {
+		switch(l4proto) {
+		case IPPROTO_TCP:
+		case IPPROTO_UDP:
+			nfct_set_attr_u8(expected, ATTR_L4PROTO, l4proto);
+			nfct_set_attr_u16(expected, ATTR_PORT_SRC, *sport);
+			nfct_set_attr_u8(mask, ATTR_L4PROTO, l4proto);
+			nfct_set_attr_u16(mask, ATTR_PORT_SRC, 0xffff);
+			break;
+		default:
+			break;
+		}
+	} else {
+		switch(l4proto) {
+		case IPPROTO_TCP:
+		case IPPROTO_UDP:
+			nfct_set_attr_u8(expected, ATTR_L4PROTO, l4proto);
+			nfct_set_attr_u16(expected, ATTR_PORT_SRC, 0x0000);
+			nfct_set_attr_u8(mask, ATTR_L4PROTO, l4proto);
+			nfct_set_attr_u16(mask, ATTR_PORT_SRC, 0x0000);
+			break;
+		default:
+			break;
+		}
+	}
+
+	switch(nfct_get_attr_u8(master, ATTR_L3PROTO)) {
+	uint32_t addr[4] = {};
+	int i;
+
+	case AF_INET:
+		nfct_set_attr_u8(expected, ATTR_L3PROTO, AF_INET);
+		nfct_set_attr_u32(expected, ATTR_IPV4_DST, daddr->ip);
+		nfct_set_attr_u32(mask, ATTR_IPV4_DST, 0xffffffff);
+		break;
+	case AF_INET6:
+		nfct_set_attr_u8(expected, ATTR_L3PROTO, AF_INET6);
+		nfct_set_attr(expected, ATTR_IPV6_DST, daddr->ip6);
+
+		for (i=0; i<4; i++)
+			memset(addr, 0xffffffff, sizeof(uint32_t));
+
+		nfct_set_attr(mask, ATTR_IPV6_DST, addr);
+		break;
+	default:
+		break;
+	}
+
+	switch(l4proto) {
+	case IPPROTO_TCP:
+	case IPPROTO_UDP:
+		nfct_set_attr_u8(expected, ATTR_L4PROTO, l4proto);
+		nfct_set_attr_u16(expected, ATTR_PORT_DST, *dport);
+		nfct_set_attr_u8(mask, ATTR_L4PROTO, l4proto);
+		nfct_set_attr_u16(mask, ATTR_PORT_DST, 0xffff);
+		break;
+	default:
+		break;
+	}
+
+	nfexp_set_attr(exp, ATTR_EXP_MASTER, master);
+	nfexp_set_attr(exp, ATTR_EXP_EXPECTED, expected);
+	nfexp_set_attr(exp, ATTR_EXP_MASK, mask);
+
+	nfct_destroy(expected);
+	nfct_destroy(mask);
+
+	return 0;
+}
+
+int cthelper_add_expect(struct nf_expect *exp)
+{
+	cthelper_test_stats.ct_expect_created++;
+	return 0;
+}
+
+int cthelper_del_expect(struct nf_expect *exp)
+{
+	return 0;
+}
+
+void
+cthelper_get_addr_src(struct nf_conntrack *ct, int dir,
+		      union nfct_attr_grp_addr *addr)
+{
+	switch (dir) {
+	case MYCT_DIR_ORIG:
+		nfct_get_attr_grp(ct, ATTR_GRP_ORIG_ADDR_SRC, addr);
+		break;
+	case MYCT_DIR_REPL:
+		nfct_get_attr_grp(ct, ATTR_GRP_REPL_ADDR_SRC, addr);
+		break;
+	}
+}
+
+void
+cthelper_get_addr_dst(struct nf_conntrack *ct, int dir,
+		      union nfct_attr_grp_addr *addr)
+{
+	switch (dir) {
+	case MYCT_DIR_ORIG:
+		nfct_get_attr_grp(ct, ATTR_GRP_ORIG_ADDR_DST, addr);
+		break;
+	case MYCT_DIR_REPL:
+		nfct_get_attr_grp(ct, ATTR_GRP_REPL_ADDR_DST, addr);
+		break;
+	}
+}
diff --git a/helpers.c b/helpers.c
new file mode 100644
index 0000000..3e4e6c8
--- /dev/null
+++ b/helpers.c
@@ -0,0 +1,76 @@
+/*
+ * (C) 2012 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 version 2 as
+ * published by the Free Software Foundation (or any later at your option).
+ *
+ * This code has been sponsored by Vyatta Inc. <http://www.vyatta.com>
+ */
+
+#include "helper.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <limits.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dlfcn.h>
+
+static LIST_HEAD(helper_list);
+
+void helper_register(struct ctd_helper *helper)
+{
+	list_add(&helper->head, &helper_list);
+}
+
+static struct ctd_helper *
+__helper_find(const char *helper_name, uint8_t l4proto)
+{
+	struct ctd_helper *cur, *helper = NULL;
+
+	list_for_each_entry(cur, &helper_list, head) {
+		if (strncmp(cur->name, helper_name, CTD_HELPER_NAME_LEN) != 0)
+			continue;
+
+		if (cur->l4proto != l4proto)
+			continue;
+
+		helper = cur;
+		break;
+	}
+	return helper;
+}
+
+struct ctd_helper *
+helper_find(const char *libdir_path,
+	    const char *helper_name, uint8_t l4proto, int flag)
+{
+	char path[PATH_MAX];
+	struct ctd_helper *helper;
+	struct stat sb;
+
+	helper = __helper_find(helper_name, l4proto);
+	if (helper != NULL)
+		return helper;
+
+	snprintf(path, sizeof(path), "%s/ct_helper_%s.so",
+		libdir_path, helper_name);
+
+	if (stat(path, &sb) != 0) {
+		if (errno == ENOENT)
+			return NULL;
+		fprintf(stderr, "%s: %s\n", path,
+			strerror(errno));
+		return NULL;
+	}
+
+	if (dlopen(path, flag) == NULL) {
+		fprintf(stderr, "%s: %s\n", path, dlerror());
+		return NULL;
+	}
+
+	return __helper_find(helper_name, l4proto);
+}
diff --git a/include/helper.h b/include/helper.h
new file mode 100644
index 0000000..9d96fb7
--- /dev/null
+++ b/include/helper.h
@@ -0,0 +1,111 @@
+#ifndef _CTD_HELPER_H_
+#define _CTD_HELPER_H_
+
+#include <stdint.h>
+#include "linux_list.h"
+#include "myct.h"
+
+#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
+
+struct pkt_buff;
+
+#define CTD_HELPER_NAME_LEN	16
+#define CTD_HELPER_POLICY_MAX	4
+
+struct ctd_helper_policy {
+	char		name[CTD_HELPER_NAME_LEN];
+	uint32_t	expect_timeout;
+	uint32_t	expect_max;
+};
+
+struct ctd_helper {
+	struct list_head	head;
+	char			name[CTD_HELPER_NAME_LEN];
+	uint8_t			l4proto;
+	int			(*cb)(struct pkt_buff *pkt,
+				      uint32_t protoff,
+				      struct myct *ct,
+				      u_int32_t ctinfo);
+
+	struct ctd_helper_policy policy[CTD_HELPER_POLICY_MAX];
+
+	int			priv_data_len;
+};
+
+struct ctd_helper_instance {
+	struct list_head	head;
+	uint32_t		queue_num;
+	uint32_t		queue_len;
+	uint16_t		l3proto;
+	uint8_t			l4proto;
+	struct ctd_helper	*helper;
+	struct ctd_helper_policy policy[CTD_HELPER_POLICY_MAX];
+};
+
+extern int cthelper_expect_init(struct nf_expect *exp, struct nf_conntrack *master, uint32_t class, union nfct_attr_grp_addr *saddr, union nfct_attr_grp_addr *daddr, uint8_t l4proto, uint16_t *sport, uint16_t *dport, uint32_t flags);
+extern int cthelper_add_expect(struct nf_expect *exp);
+extern int cthelper_del_expect(struct nf_expect *exp);
+
+extern void cthelper_get_addr_src(struct nf_conntrack *ct, int dir, union nfct_attr_grp_addr *addr);
+extern void cthelper_get_addr_dst(struct nf_conntrack *ct, int dir, union nfct_attr_grp_addr *addr);
+
+extern int in4_pton(const char *src, int srclen, uint8_t *dst, int delim, const char **end);
+extern int in6_pton(const char *src, int srclen, uint8_t *dst, int delim, const char **end);
+
+extern void helper_register(struct ctd_helper *helper);
+struct ctd_helper *helper_find(const char *libdir_path, const char *name, uint8_t l4proto, int flags);
+
+#define min_t(type, x, y) ({			\
+	type __min1 = (x);			\
+	type __min2 = (y);			\
+	__min1 < __min2 ? __min1: __min2; })
+
+#define max_t(type, x, y) ({			\
+	type __max1 = (x);			\
+	type __max2 = (y);			\
+	__max1 > __max2 ? __max1: __max2; })
+
+#define ARRAY_SIZE MNL_ARRAY_SIZE
+
+enum ip_conntrack_dir {
+	IP_CT_DIR_ORIGINAL,
+	IP_CT_DIR_REPLY,
+	IP_CT_DIR_MAX
+};
+
+/* Connection state tracking for netfilter.  This is separated from,
+   but required by, the NAT layer; it can also be used by an iptables
+   extension. */
+enum ip_conntrack_info {
+	/* Part of an established connection (either direction). */
+	IP_CT_ESTABLISHED,
+
+	/* Like NEW, but related to an existing connection, or ICMP error
+	   (in either direction). */
+	IP_CT_RELATED,
+
+	/* Started a new connection to track (only
+	   IP_CT_DIR_ORIGINAL); may be a retransmission. */
+	IP_CT_NEW,
+
+	/* >= this indicates reply direction */
+	IP_CT_IS_REPLY,
+
+	IP_CT_ESTABLISHED_REPLY = IP_CT_ESTABLISHED + IP_CT_IS_REPLY,
+	IP_CT_RELATED_REPLY = IP_CT_RELATED + IP_CT_IS_REPLY,
+	IP_CT_NEW_REPLY = IP_CT_NEW + IP_CT_IS_REPLY,
+	/* Number of distinct IP_CT types (no NEW in reply dirn). */
+	IP_CT_NUMBER = IP_CT_IS_REPLY * 2 - 1
+};
+
+#define CTINFO2DIR(ctinfo) ((ctinfo) >= IP_CT_IS_REPLY ? IP_CT_DIR_REPLY : IP_CT_DIR_ORIGINAL)
+
+#if 0
+#define pr_debug(fmt, arg...) \
+	printf(fmt, ##arg)
+#else
+#define pr_debug(fmt, arg...) \
+        ({ if (0) printf(fmt, ##arg); 0; })
+#endif
+
+#endif
diff --git a/include/linux_list.h b/include/linux_list.h
new file mode 100644
index 0000000..de182a4
--- /dev/null
+++ b/include/linux_list.h
@@ -0,0 +1,727 @@
+#ifndef _LINUX_LIST_H
+#define _LINUX_LIST_H
+
+#include <stddef.h>
+
+#undef offsetof
+#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+
+/**
+ * container_of - cast a member of a structure out to the containing structure
+ *
+ * @ptr:	the pointer to the member.
+ * @type:	the type of the container struct this is embedded in.
+ * @member:	the name of the member within the struct.
+ *
+ */
+#define container_of(ptr, type, member) ({			\
+        typeof( ((type *)0)->member ) *__mptr = (ptr);	\
+        (type *)( (char *)__mptr - offsetof(type,member) );})
+
+/*
+ * Check at compile time that something is of a particular type.
+ * Always evaluates to 1 so you may use it easily in comparisons.
+ */
+#define typecheck(type,x) \
+({	type __dummy; \
+	typeof(x) __dummy2; \
+	(void)(&__dummy == &__dummy2); \
+	1; \
+})
+
+#define prefetch(x)		1
+
+/* empty define to make this work in userspace -HW */
+#ifndef smp_wmb
+#define smp_wmb()
+#endif
+
+/*
+ * These are non-NULL pointers that will result in page faults
+ * under normal circumstances, used to verify that nobody uses
+ * non-initialized list entries.
+ */
+#define LIST_POISON1  ((void *) 0x00100100)
+#define LIST_POISON2  ((void *) 0x00200200)
+
+/*
+ * Simple doubly linked list implementation.
+ *
+ * Some of the internal functions ("__xxx") are useful when
+ * manipulating whole lists rather than single entries, as
+ * sometimes we already know the next/prev entries and we can
+ * generate better code by using them directly rather than
+ * using the generic single-entry routines.
+ */
+
+struct list_head {
+	struct list_head *next, *prev;
+};
+
+#define LIST_HEAD_INIT(name) { &(name), &(name) }
+
+#define LIST_HEAD(name) \
+	struct list_head name = LIST_HEAD_INIT(name)
+
+#define INIT_LIST_HEAD(ptr) do { \
+	(ptr)->next = (ptr); (ptr)->prev = (ptr); \
+} while (0)
+
+/*
+ * Insert a new entry between two known consecutive entries.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __list_add(struct list_head *new,
+			      struct list_head *prev,
+			      struct list_head *next)
+{
+	next->prev = new;
+	new->next = next;
+	new->prev = prev;
+	prev->next = new;
+}
+
+/**
+ * list_add - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ */
+static inline void list_add(struct list_head *new, struct list_head *head)
+{
+	__list_add(new, head, head->next);
+}
+
+/**
+ * list_add_tail - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it before
+ *
+ * Insert a new entry before the specified head.
+ * This is useful for implementing queues.
+ */
+static inline void list_add_tail(struct list_head *new, struct list_head *head)
+{
+	__list_add(new, head->prev, head);
+}
+
+/*
+ * Insert a new entry between two known consecutive entries.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __list_add_rcu(struct list_head * new,
+		struct list_head * prev, struct list_head * next)
+{
+	new->next = next;
+	new->prev = prev;
+	smp_wmb();
+	next->prev = new;
+	prev->next = new;
+}
+
+/**
+ * list_add_rcu - add a new entry to rcu-protected list
+ * @new: new entry to be added
+ * @head: list head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as list_add_rcu()
+ * or list_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * list_for_each_entry_rcu().
+ */
+static inline void list_add_rcu(struct list_head *new, struct list_head *head)
+{
+	__list_add_rcu(new, head, head->next);
+}
+
+/**
+ * list_add_tail_rcu - add a new entry to rcu-protected list
+ * @new: new entry to be added
+ * @head: list head to add it before
+ *
+ * Insert a new entry before the specified head.
+ * This is useful for implementing queues.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as list_add_tail_rcu()
+ * or list_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * list_for_each_entry_rcu().
+ */
+static inline void list_add_tail_rcu(struct list_head *new,
+					struct list_head *head)
+{
+	__list_add_rcu(new, head->prev, head);
+}
+
+/*
+ * Delete a list entry by making the prev/next entries
+ * point to each other.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __list_del(struct list_head * prev, struct list_head * next)
+{
+	next->prev = prev;
+	prev->next = next;
+}
+
+/**
+ * list_del - deletes entry from list.
+ * @entry: the element to delete from the list.
+ * Note: list_empty on entry does not return true after this, the entry is
+ * in an undefined state.
+ */
+static inline void list_del(struct list_head *entry)
+{
+	__list_del(entry->prev, entry->next);
+	entry->next = LIST_POISON1;
+	entry->prev = LIST_POISON2;
+}
+
+/**
+ * list_del_rcu - deletes entry from list without re-initialization
+ * @entry: the element to delete from the list.
+ *
+ * Note: list_empty on entry does not return true after this,
+ * the entry is in an undefined state. It is useful for RCU based
+ * lockfree traversal.
+ *
+ * In particular, it means that we can not poison the forward
+ * pointers that may still be used for walking the list.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as list_del_rcu()
+ * or list_add_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * list_for_each_entry_rcu().
+ *
+ * Note that the caller is not permitted to immediately free
+ * the newly deleted entry.  Instead, either synchronize_kernel()
+ * or call_rcu() must be used to defer freeing until an RCU
+ * grace period has elapsed.
+ */
+static inline void list_del_rcu(struct list_head *entry)
+{
+	__list_del(entry->prev, entry->next);
+	entry->prev = LIST_POISON2;
+}
+
+/**
+ * list_del_init - deletes entry from list and reinitialize it.
+ * @entry: the element to delete from the list.
+ */
+static inline void list_del_init(struct list_head *entry)
+{
+	__list_del(entry->prev, entry->next);
+	INIT_LIST_HEAD(entry);
+}
+
+/**
+ * list_move - delete from one list and add as another's head
+ * @list: the entry to move
+ * @head: the head that will precede our entry
+ */
+static inline void list_move(struct list_head *list, struct list_head *head)
+{
+        __list_del(list->prev, list->next);
+        list_add(list, head);
+}
+
+/**
+ * list_move_tail - delete from one list and add as another's tail
+ * @list: the entry to move
+ * @head: the head that will follow our entry
+ */
+static inline void list_move_tail(struct list_head *list,
+				  struct list_head *head)
+{
+        __list_del(list->prev, list->next);
+        list_add_tail(list, head);
+}
+
+/**
+ * list_empty - tests whether a list is empty
+ * @head: the list to test.
+ */
+static inline int list_empty(const struct list_head *head)
+{
+	return head->next == head;
+}
+
+/**
+ * list_empty_careful - tests whether a list is
+ * empty _and_ checks that no other CPU might be
+ * in the process of still modifying either member
+ *
+ * NOTE: using list_empty_careful() without synchronization
+ * can only be safe if the only activity that can happen
+ * to the list entry is list_del_init(). Eg. it cannot be used
+ * if another CPU could re-list_add() it.
+ *
+ * @head: the list to test.
+ */
+static inline int list_empty_careful(const struct list_head *head)
+{
+	struct list_head *next = head->next;
+	return (next == head) && (next == head->prev);
+}
+
+static inline void __list_splice(struct list_head *list,
+				 struct list_head *head)
+{
+	struct list_head *first = list->next;
+	struct list_head *last = list->prev;
+	struct list_head *at = head->next;
+
+	first->prev = head;
+	head->next = first;
+
+	last->next = at;
+	at->prev = last;
+}
+
+/**
+ * list_splice - join two lists
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ */
+static inline void list_splice(struct list_head *list, struct list_head *head)
+{
+	if (!list_empty(list))
+		__list_splice(list, head);
+}
+
+/**
+ * list_splice_init - join two lists and reinitialise the emptied list.
+ * @list: the new list to add.
+ * @head: the place to add it in the first list.
+ *
+ * The list at @list is reinitialised
+ */
+static inline void list_splice_init(struct list_head *list,
+				    struct list_head *head)
+{
+	if (!list_empty(list)) {
+		__list_splice(list, head);
+		INIT_LIST_HEAD(list);
+	}
+}
+
+/**
+ * list_entry - get the struct for this entry
+ * @ptr:	the &struct list_head pointer.
+ * @type:	the type of the struct this is embedded in.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_entry(ptr, type, member) \
+	container_of(ptr, type, member)
+
+/**
+ * list_for_each	-	iterate over a list
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ */
+#define list_for_each(pos, head) \
+	for (pos = (head)->next, prefetch(pos->next); pos != (head); \
+        	pos = pos->next, prefetch(pos->next))
+
+/**
+ * __list_for_each	-	iterate over a list
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ *
+ * This variant differs from list_for_each() in that it's the
+ * simplest possible list iteration code, no prefetching is done.
+ * Use this for code that knows the list to be very short (empty
+ * or 1 entry) most of the time.
+ */
+#define __list_for_each(pos, head) \
+	for (pos = (head)->next; pos != (head); pos = pos->next)
+
+/**
+ * list_for_each_prev	-	iterate over a list backwards
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ */
+#define list_for_each_prev(pos, head) \
+	for (pos = (head)->prev, prefetch(pos->prev); pos != (head); \
+        	pos = pos->prev, prefetch(pos->prev))
+
+/**
+ * list_for_each_safe	-	iterate over a list safe against removal of list entry
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @n:		another &struct list_head to use as temporary storage
+ * @head:	the head for your list.
+ */
+#define list_for_each_safe(pos, n, head) \
+	for (pos = (head)->next, n = pos->next; pos != (head); \
+		pos = n, n = pos->next)
+
+/**
+ * list_for_each_entry	-	iterate over list of given type
+ * @pos:	the type * to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry(pos, head, member)				\
+	for (pos = list_entry((head)->next, typeof(*pos), member),	\
+		     prefetch(pos->member.next);			\
+	     &pos->member != (head); 					\
+	     pos = list_entry(pos->member.next, typeof(*pos), member),	\
+		     prefetch(pos->member.next))
+
+/**
+ * list_for_each_entry_reverse - iterate backwards over list of given type.
+ * @pos:	the type * to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_reverse(pos, head, member)			\
+	for (pos = list_entry((head)->prev, typeof(*pos), member),	\
+		     prefetch(pos->member.prev);			\
+	     &pos->member != (head); 					\
+	     pos = list_entry(pos->member.prev, typeof(*pos), member),	\
+		     prefetch(pos->member.prev))
+
+/**
+ * list_prepare_entry - prepare a pos entry for use as a start point in
+ *			list_for_each_entry_continue
+ * @pos:	the type * to use as a start point
+ * @head:	the head of the list
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_prepare_entry(pos, head, member) \
+	((pos) ? : list_entry(head, typeof(*pos), member))
+
+/**
+ * list_for_each_entry_continue -	iterate over list of given type
+ *			continuing after existing point
+ * @pos:	the type * to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_continue(pos, head, member) 		\
+	for (pos = list_entry(pos->member.next, typeof(*pos), member),	\
+		     prefetch(pos->member.next);			\
+	     &pos->member != (head);					\
+	     pos = list_entry(pos->member.next, typeof(*pos), member),	\
+		     prefetch(pos->member.next))
+
+/**
+ * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
+ * @pos:	the type * to use as a loop counter.
+ * @n:		another type * to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ */
+#define list_for_each_entry_safe(pos, n, head, member)			\
+	for (pos = list_entry((head)->next, typeof(*pos), member),	\
+		n = list_entry(pos->member.next, typeof(*pos), member);	\
+	     &pos->member != (head); 					\
+	     pos = n, n = list_entry(n->member.next, typeof(*n), member))
+
+/**
+ * list_for_each_rcu	-	iterate over an rcu-protected list
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as list_add_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+#define list_for_each_rcu(pos, head) \
+	for (pos = (head)->next, prefetch(pos->next); pos != (head); \
+        	pos = pos->next, ({ smp_read_barrier_depends(); 0;}), prefetch(pos->next))
+
+#define __list_for_each_rcu(pos, head) \
+	for (pos = (head)->next; pos != (head); \
+        	pos = pos->next, ({ smp_read_barrier_depends(); 0;}))
+
+/**
+ * list_for_each_safe_rcu	-	iterate over an rcu-protected list safe
+ *					against removal of list entry
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @n:		another &struct list_head to use as temporary storage
+ * @head:	the head for your list.
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as list_add_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+#define list_for_each_safe_rcu(pos, n, head) \
+	for (pos = (head)->next, n = pos->next; pos != (head); \
+		pos = n, ({ smp_read_barrier_depends(); 0;}), n = pos->next)
+
+/**
+ * list_for_each_entry_rcu	-	iterate over rcu list of given type
+ * @pos:	the type * to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the list_struct within the struct.
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as list_add_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+#define list_for_each_entry_rcu(pos, head, member)			\
+	for (pos = list_entry((head)->next, typeof(*pos), member),	\
+		     prefetch(pos->member.next);			\
+	     &pos->member != (head); 					\
+	     pos = list_entry(pos->member.next, typeof(*pos), member),	\
+		     ({ smp_read_barrier_depends(); 0;}),		\
+		     prefetch(pos->member.next))
+
+
+/**
+ * list_for_each_continue_rcu	-	iterate over an rcu-protected list
+ *			continuing after existing point.
+ * @pos:	the &struct list_head to use as a loop counter.
+ * @head:	the head for your list.
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as list_add_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+#define list_for_each_continue_rcu(pos, head) \
+	for ((pos) = (pos)->next, prefetch((pos)->next); (pos) != (head); \
+        	(pos) = (pos)->next, ({ smp_read_barrier_depends(); 0;}), prefetch((pos)->next))
+
+/*
+ * Double linked lists with a single pointer list head.
+ * Mostly useful for hash tables where the two pointer list head is
+ * too wasteful.
+ * You lose the ability to access the tail in O(1).
+ */
+
+struct hlist_head {
+	struct hlist_node *first;
+};
+
+struct hlist_node {
+	struct hlist_node *next, **pprev;
+};
+
+#define HLIST_HEAD_INIT { .first = NULL }
+#define HLIST_HEAD(name) struct hlist_head name = {  .first = NULL }
+#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL)
+#define INIT_HLIST_NODE(ptr) ((ptr)->next = NULL, (ptr)->pprev = NULL)
+
+static inline int hlist_unhashed(const struct hlist_node *h)
+{
+	return !h->pprev;
+}
+
+static inline int hlist_empty(const struct hlist_head *h)
+{
+	return !h->first;
+}
+
+static inline void __hlist_del(struct hlist_node *n)
+{
+	struct hlist_node *next = n->next;
+	struct hlist_node **pprev = n->pprev;
+	*pprev = next;
+	if (next)
+		next->pprev = pprev;
+}
+
+static inline void hlist_del(struct hlist_node *n)
+{
+	__hlist_del(n);
+	n->next = LIST_POISON1;
+	n->pprev = LIST_POISON2;
+}
+
+/**
+ * hlist_del_rcu - deletes entry from hash list without re-initialization
+ * @n: the element to delete from the hash list.
+ *
+ * Note: list_unhashed() on entry does not return true after this,
+ * the entry is in an undefined state. It is useful for RCU based
+ * lockfree traversal.
+ *
+ * In particular, it means that we can not poison the forward
+ * pointers that may still be used for walking the hash list.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as hlist_add_head_rcu()
+ * or hlist_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * hlist_for_each_entry().
+ */
+static inline void hlist_del_rcu(struct hlist_node *n)
+{
+	__hlist_del(n);
+	n->pprev = LIST_POISON2;
+}
+
+static inline void hlist_del_init(struct hlist_node *n)
+{
+	if (n->pprev)  {
+		__hlist_del(n);
+		INIT_HLIST_NODE(n);
+	}
+}
+
+#define hlist_del_rcu_init hlist_del_init
+
+static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
+{
+	struct hlist_node *first = h->first;
+	n->next = first;
+	if (first)
+		first->pprev = &n->next;
+	h->first = n;
+	n->pprev = &h->first;
+}
+
+
+/**
+ * hlist_add_head_rcu - adds the specified element to the specified hlist,
+ * while permitting racing traversals.
+ * @n: the element to add to the hash list.
+ * @h: the list to add to.
+ *
+ * The caller must take whatever precautions are necessary
+ * (such as holding appropriate locks) to avoid racing
+ * with another list-mutation primitive, such as hlist_add_head_rcu()
+ * or hlist_del_rcu(), running on this same list.
+ * However, it is perfectly legal to run concurrently with
+ * the _rcu list-traversal primitives, such as
+ * hlist_for_each_entry(), but only if smp_read_barrier_depends()
+ * is used to prevent memory-consistency problems on Alpha CPUs.
+ * Regardless of the type of CPU, the list-traversal primitive
+ * must be guarded by rcu_read_lock().
+ *
+ * OK, so why don't we have an hlist_for_each_entry_rcu()???
+ */
+static inline void hlist_add_head_rcu(struct hlist_node *n,
+					struct hlist_head *h)
+{
+	struct hlist_node *first = h->first;
+	n->next = first;
+	n->pprev = &h->first;
+	smp_wmb();
+	if (first)
+		first->pprev = &n->next;
+	h->first = n;
+}
+
+/* next must be != NULL */
+static inline void hlist_add_before(struct hlist_node *n,
+					struct hlist_node *next)
+{
+	n->pprev = next->pprev;
+	n->next = next;
+	next->pprev = &n->next;
+	*(n->pprev) = n;
+}
+
+static inline void hlist_add_after(struct hlist_node *n,
+					struct hlist_node *next)
+{
+	next->next = n->next;
+	n->next = next;
+	next->pprev = &n->next;
+
+	if(next->next)
+		next->next->pprev  = &next->next;
+}
+
+#define hlist_entry(ptr, type, member) container_of(ptr,type,member)
+
+#define hlist_for_each(pos, head) \
+	for (pos = (head)->first; pos && ({ prefetch(pos->next); 1; }); \
+	     pos = pos->next)
+
+#define hlist_for_each_safe(pos, n, head) \
+	for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \
+	     pos = n)
+
+/**
+ * hlist_for_each_entry	- iterate over list of given type
+ * @tpos:	the type * to use as a loop counter.
+ * @pos:	the &struct hlist_node to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the hlist_node within the struct.
+ */
+#define hlist_for_each_entry(tpos, pos, head, member)			 \
+	for (pos = (head)->first;					 \
+	     pos && ({ prefetch(pos->next); 1;}) &&			 \
+		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
+	     pos = pos->next)
+
+/**
+ * hlist_for_each_entry_continue - iterate over a hlist continuing after existing point
+ * @tpos:	the type * to use as a loop counter.
+ * @pos:	the &struct hlist_node to use as a loop counter.
+ * @member:	the name of the hlist_node within the struct.
+ */
+#define hlist_for_each_entry_continue(tpos, pos, member)		 \
+	for (pos = (pos)->next;						 \
+	     pos && ({ prefetch(pos->next); 1;}) &&			 \
+		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
+	     pos = pos->next)
+
+/**
+ * hlist_for_each_entry_from - iterate over a hlist continuing from existing point
+ * @tpos:	the type * to use as a loop counter.
+ * @pos:	the &struct hlist_node to use as a loop counter.
+ * @member:	the name of the hlist_node within the struct.
+ */
+#define hlist_for_each_entry_from(tpos, pos, member)			 \
+	for (; pos && ({ prefetch(pos->next); 1;}) &&			 \
+		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
+	     pos = pos->next)
+
+/**
+ * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry
+ * @tpos:	the type * to use as a loop counter.
+ * @pos:	the &struct hlist_node to use as a loop counter.
+ * @n:		another &struct hlist_node to use as temporary storage
+ * @head:	the head for your list.
+ * @member:	the name of the hlist_node within the struct.
+ */
+#define hlist_for_each_entry_safe(tpos, pos, n, head, member) 		 \
+	for (pos = (head)->first;					 \
+	     pos && ({ n = pos->next; 1; }) && 				 \
+		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
+	     pos = n)
+
+/**
+ * hlist_for_each_entry_rcu - iterate over rcu list of given type
+ * @pos:	the type * to use as a loop counter.
+ * @pos:	the &struct hlist_node to use as a loop counter.
+ * @head:	the head for your list.
+ * @member:	the name of the hlist_node within the struct.
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as hlist_add_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+#define hlist_for_each_entry_rcu(tpos, pos, head, member)		 \
+	for (pos = (head)->first;					 \
+	     pos && ({ prefetch(pos->next); 1;}) &&			 \
+		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \
+	     pos = pos->next, ({ smp_read_barrier_depends(); 0; }) )
+
+#endif
diff --git a/include/myct.h b/include/myct.h
new file mode 100644
index 0000000..45d9f29
--- /dev/null
+++ b/include/myct.h
@@ -0,0 +1,43 @@
+#ifndef _MYCT_H_
+#define _MYCT_H_
+
+#include "linux_list.h"
+
+#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
+
+struct nf_conntrack;
+
+enum {
+	MYCT_NONE		= 0,
+	MYCT_ESTABLISHED	= (1 << 0),
+};
+
+enum {
+	MYCT_DIR_ORIG = 0,
+	MYCT_DIR_REPL,
+	MYCT_DIR_MAX,
+};
+
+union myct_proto {
+	uint16_t port;
+	uint16_t all;
+};
+
+struct myct_man {
+	union nfct_attr_grp_addr u3;
+	union myct_proto	u;
+	uint16_t		l3num;
+	uint8_t			protonum;
+};
+
+struct myct_tuple {
+	struct myct_man		src;
+	struct myct_man		dst;
+};
+
+struct myct {
+	struct nf_conntrack *ct;
+	void *priv_data;
+};
+
+#endif
diff --git a/l3_ipv4.c b/l3_ipv4.c
new file mode 100755
index 0000000..8edfd2e
--- /dev/null
+++ b/l3_ipv4.c
@@ -0,0 +1,86 @@
+#include <stdlib.h>
+#include <netinet/ip.h>
+#include <linux/if_ether.h>
+
+#include "proto.h"
+
+#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
+
+#define PRINT_CMP(...)
+
+static void
+l3_ipv4_ct_build_tuple(const uint8_t *pkt, struct nf_conntrack *ct)
+{
+	const struct iphdr *iph = (const struct iphdr *)pkt;
+
+	nfct_set_attr_u16(ct, ATTR_ORIG_L3PROTO, AF_INET);
+	nfct_set_attr_u16(ct, ATTR_REPL_L3PROTO, AF_INET);
+	nfct_set_attr_u32(ct, ATTR_ORIG_IPV4_SRC, iph->saddr);
+	nfct_set_attr_u32(ct, ATTR_ORIG_IPV4_DST, iph->daddr);
+	nfct_set_attr_u32(ct, ATTR_REPL_IPV4_SRC, iph->daddr);
+	nfct_set_attr_u32(ct, ATTR_REPL_IPV4_DST, iph->saddr);
+}
+
+static int
+l3_ipv4_ct_cmp_tuple_orig(const uint8_t *pkt, struct nf_conntrack *ct)
+{
+	const struct iphdr *iph = (const struct iphdr *)pkt;
+
+	PRINT_CMP("cmp_orig iph->saddr: %x == %x\n",
+		iph->saddr, nfct_get_attr_u32(ct, ATTR_ORIG_IPV4_SRC));
+	PRINT_CMP("cmp_orig iph->daddr: %x == %x\n",
+		iph->daddr, nfct_get_attr_u32(ct, ATTR_ORIG_IPV4_DST));
+
+	if (iph->saddr == nfct_get_attr_u32(ct, ATTR_ORIG_IPV4_SRC) &&
+	    iph->daddr == nfct_get_attr_u32(ct, ATTR_ORIG_IPV4_DST))
+		return 1;
+
+	return 0;
+}
+
+static int
+l3_ipv4_ct_cmp_tuple_repl(const uint8_t *pkt, struct nf_conntrack *ct)
+{
+	const struct iphdr *iph = (const struct iphdr *)pkt;
+
+	PRINT_CMP("cmp_repl iph->saddr: %x == %x\n",
+		iph->saddr, nfct_get_attr_u32(ct, ATTR_REPL_IPV4_SRC));
+	PRINT_CMP("cmp_repl iph->daddr: %x == %x\n",
+		iph->daddr, nfct_get_attr_u32(ct, ATTR_REPL_IPV4_DST));
+
+	if (iph->saddr == nfct_get_attr_u32(ct, ATTR_REPL_IPV4_SRC) &&
+	    iph->daddr == nfct_get_attr_u32(ct, ATTR_REPL_IPV4_DST))
+		return 1;
+
+	return 0;
+}
+
+static int l3_ipv4_pkt_l4proto_num(const uint8_t *pkt)
+{
+	const struct iphdr *iph = (const struct iphdr *)pkt;
+
+	return iph->protocol;
+}
+
+static int l3_ipv4_pkt_l3hdr_len(const uint8_t *pkt)
+{
+	const struct iphdr *iph = (const struct iphdr *)pkt;
+
+	return iph->ihl << 2;
+}
+
+static struct cthelper_proto_l2l3_helper ipv4 = {
+	.l2protonum	= ETH_P_IP,
+	.l3protonum	= AF_INET,
+	.l2hdr_len	= ETH_HLEN,
+	.l3ct_build	= l3_ipv4_ct_build_tuple,
+	.l3ct_cmp_orig	= l3_ipv4_ct_cmp_tuple_orig,
+	.l3ct_cmp_repl	= l3_ipv4_ct_cmp_tuple_repl,
+	.l3pkt_hdr_len	= l3_ipv4_pkt_l3hdr_len,
+	.l4pkt_proto	= l3_ipv4_pkt_l4proto_num,
+};
+
+void l2l3_ipv4_init(void)
+{
+	cthelper_proto_l2l3_helper_register(&ipv4);
+}
diff --git a/l4_tcp.c b/l4_tcp.c
new file mode 100755
index 0000000..f27c85d
--- /dev/null
+++ b/l4_tcp.c
@@ -0,0 +1,88 @@
+#include <netinet/ip.h>
+#include <netinet/tcp.h>
+
+#include "proto.h"
+
+#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
+
+#define PRINT_CMP(...)
+
+static void l4_tcp_ct_build_tuple(const uint8_t *pkt, struct nf_conntrack *ct)
+{
+	const struct tcphdr *tcph = (const struct tcphdr *)pkt;
+
+	nfct_set_attr_u8(ct, ATTR_ORIG_L4PROTO, IPPROTO_TCP);
+	nfct_set_attr_u8(ct, ATTR_REPL_L4PROTO, IPPROTO_TCP);
+	nfct_set_attr_u16(ct, ATTR_ORIG_PORT_SRC, tcph->source);
+	nfct_set_attr_u16(ct, ATTR_ORIG_PORT_DST, tcph->dest);
+	nfct_set_attr_u16(ct, ATTR_REPL_PORT_SRC, tcph->dest);
+	nfct_set_attr_u16(ct, ATTR_REPL_PORT_DST, tcph->source);
+}
+
+static int l4_tcp_ct_cmp_tuple_orig(const uint8_t *pkt, struct nf_conntrack *ct)
+{
+	const struct tcphdr *tcph = (const struct tcphdr *)pkt;
+
+	PRINT_CMP("cmp_orig tcph->source: %u == %u\n",
+		tcph->source, nfct_get_attr_u16(ct, ATTR_ORIG_PORT_SRC));
+	PRINT_CMP("cmp_orig tcph->dest: %u == %u\n",
+		tcph->dest, nfct_get_attr_u16(ct, ATTR_ORIG_PORT_DST));
+
+	if (tcph->source == nfct_get_attr_u16(ct, ATTR_ORIG_PORT_SRC) &&
+	    tcph->dest == nfct_get_attr_u16(ct, ATTR_ORIG_PORT_DST))
+		return 1;
+
+	return 0;
+}
+
+static int
+l4_tcp_ct_cmp_tuple_repl(const uint8_t *pkt, struct nf_conntrack *ct)
+{
+	const struct tcphdr *tcph = (const struct tcphdr *)pkt;
+
+	PRINT_CMP("cmp_repl tcph->source: %u == %u\n",
+		tcph->source, nfct_get_attr_u16(ct, ATTR_REPL_PORT_SRC));
+	PRINT_CMP("cmp_repl tcph->dest: %u == %u\n",
+		tcph->dest, nfct_get_attr_u16(ct, ATTR_REPL_PORT_DST));
+
+	if (tcph->source == nfct_get_attr_u16(ct, ATTR_REPL_PORT_SRC) &&
+	    tcph->dest == nfct_get_attr_u16(ct, ATTR_REPL_PORT_DST))
+		return 1;
+
+	return 0;
+}
+
+static int
+l4_tcp_ct_cmp_port(struct nf_conntrack *ct, uint16_t port)
+{
+	PRINT_CMP("cmp_port src: %u == %u\n",
+		port, nfct_get_attr_u16(ct, ATTR_ORIG_PORT_SRC));
+	PRINT_CMP("cmp_port dst: %u == %u\n",
+		port, nfct_get_attr_u16(ct, ATTR_ORIG_PORT_DST));
+
+	if (port == nfct_get_attr_u16(ct, ATTR_ORIG_PORT_SRC) ||
+	    port == nfct_get_attr_u16(ct, ATTR_ORIG_PORT_DST))
+		return 1;
+
+	return 0;
+}
+
+static int l4_tcp_pkt_no_data(const uint8_t *pkt)
+{
+	const struct tcphdr *tcph = (const struct tcphdr *)pkt;
+	return tcph->syn || tcph->fin || tcph->rst || !tcph->psh;
+}
+
+static struct cthelper_proto_l4_helper tcp = {
+	.l4protonum	= IPPROTO_TCP,
+	.l4ct_build	= l4_tcp_ct_build_tuple,
+	.l4ct_cmp_orig	= l4_tcp_ct_cmp_tuple_orig,
+	.l4ct_cmp_repl	= l4_tcp_ct_cmp_tuple_repl,
+	.l4ct_cmp_port	= l4_tcp_ct_cmp_port,
+	.l4pkt_no_data	= l4_tcp_pkt_no_data,
+};
+
+void l4_tcp_init(void)
+{
+	cthelper_proto_l4_helper_register(&tcp);
+}
diff --git a/l4_udp.c b/l4_udp.c
new file mode 100755
index 0000000..4d52d0a
--- /dev/null
+++ b/l4_udp.c
@@ -0,0 +1,88 @@
+#include <netinet/ip.h>
+#include <netinet/udp.h>
+
+#include "proto.h"
+
+#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
+
+#define PRINT_CMP(...)
+
+static void l4_udp_ct_build_tuple(const uint8_t *pkt, struct nf_conntrack *ct)
+{
+	const struct udphdr *udph = (const struct udphdr *)pkt;
+
+	nfct_set_attr_u8(ct, ATTR_ORIG_L4PROTO, IPPROTO_UDP);
+	nfct_set_attr_u8(ct, ATTR_REPL_L4PROTO, IPPROTO_UDP);
+	nfct_set_attr_u16(ct, ATTR_ORIG_PORT_SRC, udph->source);
+	nfct_set_attr_u16(ct, ATTR_ORIG_PORT_DST, udph->dest);
+	nfct_set_attr_u16(ct, ATTR_REPL_PORT_SRC, udph->dest);
+	nfct_set_attr_u16(ct, ATTR_REPL_PORT_DST, udph->source);
+}
+
+static int l4_udp_ct_cmp_tuple_orig(const uint8_t *pkt, struct nf_conntrack *ct)
+{
+	const struct udphdr *udph = (const struct udphdr *)pkt;
+
+	PRINT_CMP("cmp_orig udph->source: %u == %u\n",
+		udph->source, nfct_get_attr_u16(ct, ATTR_ORIG_PORT_SRC));
+	PRINT_CMP("cmp_orig udph->dest: %u == %u\n",
+		udph->dest, nfct_get_attr_u16(ct, ATTR_ORIG_PORT_DST));
+
+	if (udph->source == nfct_get_attr_u16(ct, ATTR_ORIG_PORT_SRC) &&
+	    udph->dest == nfct_get_attr_u16(ct, ATTR_ORIG_PORT_DST))
+		return 1;
+
+	return 0;
+}
+
+static int
+l4_udp_ct_cmp_tuple_repl(const uint8_t *pkt, struct nf_conntrack *ct)
+{
+	const struct udphdr *udph = (const struct udphdr *)pkt;
+
+	PRINT_CMP("cmp_repl udph->source: %u == %u\n",
+		udph->source, nfct_get_attr_u16(ct, ATTR_REPL_PORT_SRC));
+	PRINT_CMP("cmp_repl udph->dest: %u == %u\n",
+		udph->dest, nfct_get_attr_u16(ct, ATTR_REPL_PORT_DST));
+
+	if (udph->source == nfct_get_attr_u16(ct, ATTR_REPL_PORT_SRC) &&
+	    udph->dest == nfct_get_attr_u16(ct, ATTR_REPL_PORT_DST))
+		return 1;
+
+	return 0;
+}
+
+static int
+l4_udp_ct_cmp_port(struct nf_conntrack *ct, uint16_t port)
+{
+	PRINT_CMP("cmp_port src: %u == %u\n",
+		port, nfct_get_attr_u16(ct, ATTR_ORIG_PORT_SRC));
+	PRINT_CMP("cmp_port dst: %u == %u\n",
+		port, nfct_get_attr_u16(ct, ATTR_ORIG_PORT_DST));
+
+	if (port == nfct_get_attr_u16(ct, ATTR_ORIG_PORT_SRC) ||
+	    port == nfct_get_attr_u16(ct, ATTR_ORIG_PORT_DST))
+		return 1;
+
+	return 0;
+}
+
+static int l4_udp_pkt_no_data(const uint8_t *pkt)
+{
+	/* UDP has no control packets. */
+	return 1;
+}
+
+static struct cthelper_proto_l4_helper tcp = {
+	.l4protonum	= IPPROTO_UDP,
+	.l4ct_build	= l4_udp_ct_build_tuple,
+	.l4ct_cmp_orig	= l4_udp_ct_cmp_tuple_orig,
+	.l4ct_cmp_repl	= l4_udp_ct_cmp_tuple_repl,
+	.l4ct_cmp_port	= l4_udp_ct_cmp_port,
+	.l4pkt_no_data	= l4_udp_pkt_no_data,
+};
+
+void l4_udp_init(void)
+{
+	cthelper_proto_l4_helper_register(&tcp);
+}
diff --git a/main.c b/main.c
new file mode 100755
index 0000000..73f4a16
--- /dev/null
+++ b/main.c
@@ -0,0 +1,220 @@
+#include <stdio.h>
+#include <pcap.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+#include <string.h>
+#include <dlfcn.h>
+
+#include "ct.h"
+#include "proto.h"
+#include "include/helper.h"
+#include "test.h"
+
+#include <libnetfilter_queue/pktbuff.h>
+
+struct cthelper_test_stats cthelper_test_stats;
+
+enum {
+	TEST_NORMAL = 0,
+	TEST_DNAT,
+};
+
+static int
+cthelper_process_packet(const uint8_t *pkt, uint32_t pktlen,
+			struct ctd_helper *h, int proto, uint16_t port,
+			int type)
+{
+	struct pkt_buff *pktb;
+	struct cthelper_proto_l2l3_helper *l3h;
+	struct cthelper_proto_l4_helper *l4h;
+	unsigned int l3hdr_len, l4protonum;
+	struct nf_ct_entry *ct;
+	int ret, this_proto;
+	uint32_t dataoff, ctinfo = 0;
+
+	l3h = cthelper_proto_l2l3_helper_find(pkt, &l4protonum, &l3hdr_len);
+	if (l3h == NULL) {
+		fprintf(stderr, "Unsupported layer 3 protocol, skipping.\n");
+		return -1;
+	}
+
+	l4h = cthelper_proto_l4_helper_find(pkt, l4protonum);
+	if (l4h == NULL) {
+		fprintf(stderr, "Unsupported layer 4 protocol, skipping.\n");
+		return -1;
+	}
+	/* get layer 3 header. */
+	pkt += l3h->l2hdr_len;
+	pktlen -= l3h->l2hdr_len;
+
+	/* skip packet with mismatching protocol */
+	this_proto = l3h->l4pkt_proto(pkt);
+	if (this_proto != proto) {
+		cthelper_test_stats.pkt_mismatch_proto++;
+		return 0;
+	}
+
+	/* Look for the fake conntrack. */
+	ct = ct_find(pkt, l3hdr_len, l3h, l4h, &ctinfo);
+	if (ct == NULL) {
+		/* It doesn't exist any, create one. */
+		ct = ct_alloc(pkt, l3hdr_len, l3h, l4h);
+		if (ct == NULL) {
+			fprintf(stderr, "Not enough memory\n");
+			return -1;
+		}
+		ct_add(ct);
+		ctinfo += IP_CT_NEW;
+	} else
+		ctinfo += IP_CT_ESTABLISHED;
+
+	/* skip packets with mismatching ports */
+	if (!l4h->l4ct_cmp_port(ct->myct->ct, ntohs(port))) {
+		cthelper_test_stats.pkt_mismatch_port++;
+		return -1;
+	}
+
+	/*
+	 * FIXME: reminder, implement this below in the kernel for cthelper.
+	 */
+
+	/* This packet contains no data, skip it. */
+/*	if (l4h->l4pkt_no_data && l4h->l4pkt_no_data(pkt + l3hdr_len)) {
+		NFG_DEBUG("skipping packet with no data\n");
+		continue;
+	} */
+
+	/* Create the fake network buffer. */
+	pktb = pktb_alloc(AF_INET, pkt, pktlen, 128);
+	if (pktb == NULL) {
+		fprintf(stderr, "Not enough memory\n");
+		return -1;
+	}
+
+	dataoff = l3h->l3pkt_hdr_len(pkt);
+	if (dataoff > pktb_len(pktb)) {
+		fprintf(stderr, "wrong layer 3 offset: %d > %d\n",
+			dataoff, pktb_len(pktb));
+		return -1;
+	}
+
+	/* tweak to run DNAT mangling code using the same PCAP file. */
+	if (type == TEST_DNAT) {
+		struct nf_conntrack *tmp = ct->myct->ct;
+		/* as long as this is tested, who cares the destination IP? */
+		in_addr_t addr = inet_addr("1.1.1.1");
+
+		/* clone the real conntrack, to add DNAT information */
+		ct->myct->ct = nfct_clone(ct->myct->ct);
+		/* set fake DNAT information */
+		nfct_set_attr_u32(ct->myct->ct, ATTR_STATUS, IPS_DST_NAT);
+		nfct_set_attr_u32(ct->myct->ct, ATTR_ORIG_IPV4_DST, addr);
+		/* pass it to helper */
+		ret = h->cb(pktb, dataoff, ct->myct, ctinfo);
+		/* restore real conntrack */
+		nfct_destroy(ct->myct->ct);
+		ct->myct->ct = tmp;
+
+		if (pktb_mangled(pktb)) {
+			uint32_t i;
+			uint8_t *data = pktb_network_header(pktb);
+
+			printf("\e[1;31mmangled content: ");
+
+			for (i=0; i < pktb_len(pktb); i++)
+				printf("%c", data[i]);
+
+			printf("\e[0m\n");
+		}
+	} else
+		ret = h->cb(pktb, dataoff, ct->myct, ctinfo);
+
+	pktb_free(pktb);
+
+	return ret;
+}
+
+static int
+cthelper_test(const char *pcapfile, const char *helper_name,
+	      int l4proto, uint16_t port, int type)
+{
+	struct pcap_pkthdr pcaph;
+	char errbuf[PCAP_ERRBUF_SIZE];
+	const u_char *pkt;
+	pcap_t *handle;
+	struct ctd_helper *h;
+
+	h = helper_find("/usr/lib/conntrack-tools",
+			helper_name, l4proto, RTLD_NOW);
+	if (h == NULL) {
+		fprintf(stderr, "couldn't find helper: %s\n", helper_name);
+		return -1;
+	}
+
+	handle = pcap_open_offline(pcapfile, errbuf);
+	if (handle == NULL) {
+		fprintf(stderr, "couldn't open pcap file %s: %s\n",
+				pcapfile, errbuf);
+		return -1;
+	}
+	while ((pkt = pcap_next(handle, &pcaph)) != NULL) {
+		cthelper_test_stats.pkts++;
+		cthelper_process_packet(pkt, pcaph.caplen, h, l4proto, port,
+					type);
+	}
+
+	ct_flush();
+	pcap_close(handle);
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	int ret, l4proto, type = TEST_NORMAL;
+
+	if (argc < 5 || argc > 6) {
+		fprintf(stderr, "Wrong usage:\n");
+		fprintf(stderr, "%s <pcap_file> <helper-name> <proto> "
+				"<port> [dnat]\n",
+				argv[0]);
+		fprintf(stderr, "example: %s file.pcap ftp tcp 21\n", argv[0]);
+		exit(EXIT_FAILURE);
+	}
+	if (strncmp("tcp", argv[3], strlen("tcp")) == 0)
+		l4proto = IPPROTO_TCP;
+	else if (strncmp("udp", argv[3], strlen("udp")) == 0)
+		l4proto = IPPROTO_UDP;
+	else {
+		fprintf(stderr, "%s not supported, send a patch to Pablo\n",
+			argv[3]);
+		exit(EXIT_FAILURE);
+	}
+	if (argc == 6) {
+		if (strncmp("dnat", argv[5], strlen("dnat")) == 0) {
+			type = TEST_DNAT;
+			printf("test dnat\n");
+		}
+	}
+
+	/* Initialization of supported layer 3 and 4 protocols here. */
+	l2l3_ipv4_init();
+	l4_tcp_init();
+	l4_udp_init();
+
+	if (cthelper_test(argv[1], argv[2], l4proto, atoi(argv[4]), type) < 0)
+		ret = EXIT_FAILURE;
+	else
+		ret = EXIT_SUCCESS;
+
+	printf("\e[1;34mTest results: expect_created=%d packets=%d "
+	       "packets_skipped=%d\e[0m\n",
+		cthelper_test_stats.ct_expect_created,
+		cthelper_test_stats.pkts,
+		cthelper_test_stats.pkt_mismatch_proto +
+		cthelper_test_stats.pkt_mismatch_port);
+
+	return ret;
+}
diff --git a/pcaps/nfsv3.pcap b/pcaps/nfsv3.pcap
new file mode 100644
index 0000000..04606bd
--- /dev/null
+++ b/pcaps/nfsv3.pcap
diff --git a/pcaps/oracle-tns-redirect.pcap b/pcaps/oracle-tns-redirect.pcap
new file mode 100644
index 0000000..32f8952
--- /dev/null
+++ b/pcaps/oracle-tns-redirect.pcap
diff --git a/proto.c b/proto.c
new file mode 100755
index 0000000..6a1f345
--- /dev/null
+++ b/proto.c
@@ -0,0 +1,49 @@
+#include <stdlib.h>
+#include <netinet/in.h>
+#include <linux/if_ether.h>
+
+#include "linux_list.h"
+#include "proto.h"
+
+static LIST_HEAD(l2l3_helper_list);
+static LIST_HEAD(l4_helper_list);
+
+struct cthelper_proto_l2l3_helper *
+cthelper_proto_l2l3_helper_find(const uint8_t *pkt,
+				unsigned int *l4protonum,
+				unsigned int *l3hdr_len)
+{
+	const struct ethhdr *eh = (const struct ethhdr *)pkt;
+	struct cthelper_proto_l2l3_helper *cur;
+
+	list_for_each_entry(cur, &l2l3_helper_list, head) {
+		if (ntohs(cur->l2protonum) == eh->h_proto) {
+			*l4protonum = cur->l4pkt_proto(pkt + ETH_HLEN);
+			*l3hdr_len = cur->l3pkt_hdr_len(pkt + ETH_HLEN);
+			return cur;
+		}
+	}
+	return NULL;
+}
+
+void cthelper_proto_l2l3_helper_register(struct cthelper_proto_l2l3_helper *h)
+{
+	list_add(&h->head, &l2l3_helper_list);
+}
+
+struct cthelper_proto_l4_helper *
+cthelper_proto_l4_helper_find(const uint8_t *pkt, unsigned int l4protocol)
+{
+	struct cthelper_proto_l4_helper *cur;
+
+	list_for_each_entry(cur, &l4_helper_list, head) {
+		if (cur->l4protonum == l4protocol)
+			return cur;
+	}
+	return NULL;
+}
+
+void cthelper_proto_l4_helper_register(struct cthelper_proto_l4_helper *h)
+{
+	list_add(&h->head, &l4_helper_list);
+}
diff --git a/proto.h b/proto.h
new file mode 100755
index 0000000..e81460f
--- /dev/null
+++ b/proto.h
@@ -0,0 +1,50 @@
+#ifndef _HELPER_H_
+#define _HELPER_H_
+
+#include <stdint.h>
+
+#include "include/linux_list.h"
+
+struct nf_conntrack;
+
+struct cthelper_proto_l4_helper {
+	struct list_head	head;
+
+	unsigned int		l4protonum;
+
+	void	(*l4ct_build)(const uint8_t *pkt, struct nf_conntrack *ct);
+	int	(*l4ct_cmp_orig)(const uint8_t *pkt, struct nf_conntrack *ct);
+	int	(*l4ct_cmp_repl)(const uint8_t *pkt, struct nf_conntrack *ct);
+	int	(*l4ct_cmp_port)(struct nf_conntrack *ct, uint16_t port);
+
+	int	(*l4pkt_no_data)(const uint8_t *pkt);
+};
+
+struct cthelper_proto_l2l3_helper {
+	struct list_head	head;
+
+	unsigned int		l2protonum;
+	unsigned int		l2hdr_len;
+
+	unsigned int		l3protonum;
+
+	void	(*l3ct_build)(const uint8_t *pkt, struct nf_conntrack *ct);
+	int 	(*l3ct_cmp_orig)(const uint8_t *pkt, struct nf_conntrack *ct);
+	int 	(*l3ct_cmp_repl)(const uint8_t *pkt, struct nf_conntrack *ct);
+
+	int	(*l3pkt_hdr_len)(const uint8_t *pkt);
+	int	(*l4pkt_proto)(const uint8_t *pkt);
+};
+
+struct cthelper_proto_l2l3_helper *cthelper_proto_l2l3_helper_find(const uint8_t *pkt, unsigned int *l4protonum, unsigned int *l3hdr_len);
+void cthelper_proto_l2l3_helper_register(struct cthelper_proto_l2l3_helper *h);
+
+struct cthelper_proto_l4_helper *cthelper_proto_l4_helper_find(const uint8_t *pkt, unsigned int l4protonum);
+void cthelper_proto_l4_helper_register(struct cthelper_proto_l4_helper *h);
+
+/* Initialization of supported protocols here. */
+void l2l3_ipv4_init(void);
+void l4_tcp_init(void);
+void l4_udp_init(void);
+
+#endif
diff --git a/run-test.sh b/run-test.sh
new file mode 100644
index 0000000..fe31602
--- /dev/null
+++ b/run-test.sh
@@ -0,0 +1,11 @@
+echo "Running test for oracle TNS port 1521"
+./cthelper-test pcaps/oracle-tns-redirect.pcap tns tcp 1521
+
+echo "Running test for oracle TNS port 1521"
+./cthelper-test pcaps/oracle-tns-redirect.pcap tns tcp 1521 dnat
+
+echo "Running test for NFSv3 UDP port 111"
+./cthelper-test pcaps/nfsv3.pcap rpc udp 111
+
+echo "Running test for NFSv3 TCP port 111"
+./cthelper-test pcaps/nfsv3.pcap rpc tcp 111
diff --git a/test.h b/test.h
new file mode 100644
index 0000000..4f5a6b6
--- /dev/null
+++ b/test.h
@@ -0,0 +1,13 @@
+#ifndef _CTHELPER_TEST_H_
+#define _CTHELPER_TEST_H_
+
+struct cthelper_test_stats {
+	int	pkts;
+	int	pkt_mismatch_proto;
+	int	pkt_mismatch_port;
+	int	ct_expect_created;
+};
+
+extern struct cthelper_test_stats cthelper_test_stats;
+
+#endif