Patchwork [iptables-nftables,RFC,v3,04/16] nft: Integrate nft translator engine in current core

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Submitter Tomasz Bursztyka
Date Aug. 9, 2013, 1:31 p.m.
Message ID <1376055090-26551-5-git-send-email-tomasz.bursztyka@linux.intel.com>
Download mbox | patch
Permalink /patch/266028/
State RFC
Headers show

Comments

Tomasz Bursztyka - Aug. 9, 2013, 1:31 p.m.
First step of using the nft translation engine: supporting basic rule
information to recreat the command structure.

Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
---
 iptables/Makefile.am  |   2 +-
 iptables/nft-ipv4.c   |  23 ++++-
 iptables/nft-ipv6.c   |   9 +-
 iptables/nft-shared.c | 255 ++++++++++++++++++++++++++++++++++++--------------
 iptables/nft-shared.h |  16 +++-
 iptables/nft.c        |   3 +
 6 files changed, 224 insertions(+), 84 deletions(-)
Pablo Neira - Aug. 9, 2013, 9:24 p.m.
Hi Tomasz,

On Fri, Aug 09, 2013 at 04:31:18PM +0300, Tomasz Bursztyka wrote:
[...]
> +static int nft_parse_ip_addresses(struct nft_trans_rule_context *rule_ctx,
> +				  struct nft_trans_instruction_context *first,
> +				  struct nft_trans_instruction_context *last,
> +				  nft_trans_parse_callback_f user_cb,
> +				  void *user_data)
> +{
> +	struct nft_to_cs_data *i2cs = user_data;
> +	struct nft_rule_expr *e1, *e2;
> +	struct nft_family_ops *ops;
> +	uint32_t offset;
> +
> +	e1 = nft_trans_instruction_context_get_expr(first);
> +	if (!nft_rule_expr_is_set(e1, NFT_EXPR_PAYLOAD_OFFSET))
> +		return -1;
> +
> +	offset = nft_rule_expr_get_u32(e1, NFT_EXPR_PAYLOAD_OFFSET);
> +	ops = nft_family_ops_lookup(i2cs->family);
> +
> +	first = nft_trans_instruction_context_get_next(first);
> +	e1 = nft_trans_instruction_context_get_expr(first);
> +	e2 = nft_trans_instruction_context_get_expr(last);
> +
> +	ops->parse_payload(e1, e2, i2cs->cs, offset);
> +
> +	return 0;
> +}
> +
[...]
> +static struct nft_trans_instruction nft_ipt_io_ifs = {
> +	.instructions = nft_ipt_io_ifs_instructions,
> +	.function = nft_parse_io_ifs,
> +};
> +
> +static enum nft_instruction nft_ipt_ip_addr_instructions_1[] = {
> +	NFT_INSTRUCTION_PAYLOAD, NFT_INSTRUCTION_CMP,
> +	NFT_INSTRUCTION_MAX,
> +};
> +
> +static struct nft_trans_instruction nft_ipt_ip_addr_1 = {
> +	.instructions = nft_ipt_ip_addr_instructions_1,
> +	.function = nft_parse_ip_addresses,
> +};
> +
> +static enum nft_instruction nft_ipt_ip_addr_instructions_2[] = {
> +	NFT_INSTRUCTION_PAYLOAD, NFT_INSTRUCTION_BITWISE, NFT_INSTRUCTION_CMP,
> +	NFT_INSTRUCTION_MAX,
> +};

If I understood this correctly, your approach uses the array of
instructions above as keys to look up for the corresponding parser. In
that case, I'm afraid that this engine won't cover the complexity of
the payload instructions since we'll end up having *a lot* of matching
combinations that will overlap in your tree. You cannot resolve that
ambiguity problem of what parser needs to be invoked without looking
at other information that is contained in the instruction, eg. payload
base and offset.

Regards.
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Tomasz Bursztyka - Aug. 12, 2013, 7:15 a.m.
Hi Pablo,

> If I understood this correctly, your approach uses the array of
> instructions above as keys to look up for the corresponding parser. In
> that case, I'm afraid that this engine won't cover the complexity of
> the payload instructions since we'll end up having*a lot*  of matching
> combinations that will overlap in your tree. You cannot resolve that
> ambiguity problem of what parser needs to be invoked without looking
> at other information that is contained in the instruction, eg. payload
> base and offset.

It already handles overlapping patterns. I decided to go the simplest way:
- you can register as many parser you want for a pattern, of course.
- engine will try as many parser it has for a pattern as long as those 
return -1, the one who returns 0 wins (engine tries then to continue on 
next expressions, finding other patterns)
- engine follows longest pattern first: so if no parser as won on the 
current pattern, engine will start to go backward. (it will try to match 
shorter pattern)

Have a look at nft_trans_add_instruction(), 
retrieve_nft_trans_instructions() and execute_relevant_instruction() for 
insights.

Sure it's definitely not the most optimized but I believe it should be 
sufficient for our concerns.
And anyway, the API is good enough so the engine itself can be 
transparently improved if necessary.

Tomasz


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Patch

diff --git a/iptables/Makefile.am b/iptables/Makefile.am
index dc8af34..3a7983c 100644
--- a/iptables/Makefile.am
+++ b/iptables/Makefile.am
@@ -32,7 +32,7 @@  xtables_multi_SOURCES += xtables-save.c xtables-restore.c \
 			 xtables-standalone.c xtables.c nft.c \
 			 nft-shared.c nft-ipv4.c nft-ipv6.c \
 			 xtables-config.c xtables-events.c
-xtables_multi_LDADD   += -lmnl -lnftables ${libmnl_LIBS} ${libnftables_LIBS}
+xtables_multi_LDADD   += -lmnl -lnftables ${libmnl_LIBS} ${libnftables_LIBS} ../libnfttrans/libnfttrans.la
 xtables_multi_CFLAGS  += -DENABLE_NFTABLES
 # yacc and lex generate dirty code
 xtables_multi-xtables-config-parser.o xtables_multi-xtables-config-syntax.o: AM_CFLAGS += -Wno-missing-prototypes -Wno-missing-declarations -Wno-implicit-function-declaration -Wno-nested-externs -Wno-undef -Wno-redundant-decls
diff --git a/iptables/nft-ipv4.c b/iptables/nft-ipv4.c
index 81be9f4..038d04f 100644
--- a/iptables/nft-ipv4.c
+++ b/iptables/nft-ipv4.c
@@ -85,6 +85,18 @@  static bool nft_ipv4_is_same(const struct iptables_command_state *a,
 				  b->fw.ip.iniface_mask, b->fw.ip.outiface_mask);
 }
 
+static void get_frag_from_expr(struct nft_rule_expr *e, bool *inv)
+{
+	uint8_t op;
+
+	/* e is directly pointing to the cmp expr */
+	op = nft_rule_expr_get_u8(e, NFT_EXPR_CMP_OP);
+	if (op == NFT_CMP_EQ)
+		*inv = true;
+	else
+		*inv = false;
+}
+
 static void get_frag(struct nft_rule_expr_iter *iter, bool *inv)
 {
 	struct nft_rule_expr *e;
@@ -207,7 +219,8 @@  static void nft_ipv4_parse_meta(struct nft_rule_expr *e, uint8_t key,
 		   &cs->fw.ip.invflags);
 }
 
-static void nft_ipv4_parse_payload(struct nft_rule_expr_iter *iter,
+static void nft_ipv4_parse_payload(struct nft_rule_expr *e_1,
+				   struct nft_rule_expr *e_2,
 				   struct iptables_command_state *cs,
 				   uint32_t offset)
 {
@@ -217,28 +230,28 @@  static void nft_ipv4_parse_payload(struct nft_rule_expr_iter *iter,
 	bool inv;
 
 	case offsetof(struct iphdr, saddr):
-		get_cmp_data(iter, &addr, sizeof(addr), &inv);
+		get_expr_cmp_data(e_1, &addr, sizeof(addr), &inv);
 		cs->fw.ip.src.s_addr = addr.s_addr;
 		cs->fw.ip.smsk.s_addr = 0xffffffff;
 		if (inv)
 			cs->fw.ip.invflags |= IPT_INV_SRCIP;
 		break;
 	case offsetof(struct iphdr, daddr):
-		get_cmp_data(iter, &addr, sizeof(addr), &inv);
+		get_expr_cmp_data(e_1, &addr, sizeof(addr), &inv);
 		cs->fw.ip.dst.s_addr = addr.s_addr;
 		cs->fw.ip.dmsk.s_addr = 0xffffffff;
 		if (inv)
 			cs->fw.ip.invflags |= IPT_INV_DSTIP;
 		break;
 	case offsetof(struct iphdr, protocol):
-		get_cmp_data(iter, &proto, sizeof(proto), &inv);
+		get_expr_cmp_data(e_1, &proto, sizeof(proto), &inv);
 		cs->fw.ip.proto = proto;
 		if (inv)
 			cs->fw.ip.invflags |= IPT_INV_PROTO;
 		break;
 	case offsetof(struct iphdr, frag_off):
 		cs->fw.ip.flags |= IPT_F_FRAG;
-		get_frag(iter, &inv);
+		get_frag_from_expr(e_2, &inv);
 		if (inv)
 			cs->fw.ip.invflags |= IPT_INV_FRAG;
 		break;
diff --git a/iptables/nft-ipv6.c b/iptables/nft-ipv6.c
index 0214dcf..5c79912 100644
--- a/iptables/nft-ipv6.c
+++ b/iptables/nft-ipv6.c
@@ -119,7 +119,8 @@  static void nft_ipv6_parse_meta(struct nft_rule_expr *e, uint8_t key,
 		   cs->fw6.ipv6.outiface_mask, &cs->fw6.ipv6.invflags);
 }
 
-static void nft_ipv6_parse_payload(struct nft_rule_expr_iter *iter,
+static void nft_ipv6_parse_payload(struct nft_rule_expr *e_1,
+				   struct nft_rule_expr *e_2,
 				   struct iptables_command_state *cs,
 				   uint32_t offset)
 {
@@ -129,19 +130,19 @@  static void nft_ipv6_parse_payload(struct nft_rule_expr_iter *iter,
 	bool inv;
 
 	case offsetof(struct ip6_hdr, ip6_src):
-		get_cmp_data(iter, &addr, sizeof(addr), &inv);
+		get_expr_cmp_data(e_1, &addr, sizeof(addr), &inv);
 		memcpy(cs->fw6.ipv6.src.s6_addr, &addr, sizeof(addr));
 		if (inv)
 			cs->fw6.ipv6.invflags |= IPT_INV_SRCIP;
 		break;
 	case offsetof(struct ip6_hdr, ip6_dst):
-		get_cmp_data(iter, &addr, sizeof(addr), &inv);
+		get_expr_cmp_data(e_1, &addr, sizeof(addr), &inv);
 		memcpy(cs->fw6.ipv6.dst.s6_addr, &addr, sizeof(addr));
 		if (inv)
 			cs->fw6.ipv6.invflags |= IPT_INV_DSTIP;
 		break;
 	case offsetof(struct ip6_hdr, ip6_nxt):
-		get_cmp_data(iter, &proto, sizeof(proto), &inv);
+		get_expr_cmp_data(e_1, &proto, sizeof(proto), &inv);
 		cs->fw6.ipv6.flags |= IP6T_F_PROTO;
 		cs->fw6.ipv6.proto = proto;
 		if (inv)
diff --git a/iptables/nft-shared.c b/iptables/nft-shared.c
index dd4766b..614b7ae 100644
--- a/iptables/nft-shared.c
+++ b/iptables/nft-shared.c
@@ -28,6 +28,8 @@ 
 #include "nft-shared.h"
 #include "xshared.h"
 
+struct nft_trans_instruction_tree *xt_nft_tree;
+
 extern struct nft_family_ops nft_family_ops_ipv4;
 extern struct nft_family_ops nft_family_ops_ipv6;
 
@@ -349,21 +351,16 @@  void print_proto(uint16_t proto, int invert)
 	printf("-p %u ", proto);
 }
 
-void get_cmp_data(struct nft_rule_expr_iter *iter,
-		  void *data, size_t dlen, bool *inv)
+void get_expr_cmp_data(struct nft_rule_expr *e,
+		       void *data, size_t dlen, bool *inv)
 {
-	struct nft_rule_expr *e;
 	const char *name;
 	size_t len;
 	uint8_t op;
 
-	e = nft_rule_expr_iter_next(iter);
-	if (e == NULL)
-		return;
-
 	name = nft_rule_expr_get_str(e, NFT_RULE_EXPR_ATTR_NAME);
 	if (strcmp(name, "cmp") != 0) {
-		DEBUGP("skipping no cmp after meta\n");
+		DEBUGP("skipping - Not a cmp expression\n");
 		return;
 	}
 
@@ -375,105 +372,154 @@  void get_cmp_data(struct nft_rule_expr_iter *iter,
 		*inv = false;
 }
 
-static void
-nft_parse_meta(struct nft_rule_expr *e, struct nft_rule_expr_iter *iter,
-	       int family, struct iptables_command_state *cs)
+void get_cmp_data(struct nft_rule_expr_iter *iter,
+		  void *data, size_t dlen, bool *inv)
 {
-	uint8_t key = nft_rule_expr_get_u8(e, NFT_EXPR_META_KEY);
-	struct nft_family_ops *ops = nft_family_ops_lookup(family);
-	const char *name;
+	struct nft_rule_expr *e;
 
 	e = nft_rule_expr_iter_next(iter);
 	if (e == NULL)
 		return;
 
-	name = nft_rule_expr_get_str(e, NFT_RULE_EXPR_ATTR_NAME);
-	if (strcmp(name, "cmp") != 0) {
-		DEBUGP("skipping no cmp after meta\n");
-		return;
-	}
-
-	ops->parse_meta(e, key, cs);
+	get_expr_cmp_data(e, data, dlen, inv);
 }
 
-static void
-nft_parse_payload(struct nft_rule_expr *e, struct nft_rule_expr_iter *iter,
-		  int family, struct iptables_command_state *cs)
+static int
+nft_parse_counters(struct nft_trans_rule_context *rule_ctx,
+		   struct nft_trans_instruction_context *first,
+		   struct nft_trans_instruction_context *useless,
+		   nft_trans_parse_callback_f user_cb,
+		   void *user_data)
 {
-	struct nft_family_ops *ops = nft_family_ops_lookup(family);
-	uint32_t offset;
+	struct nft_to_cs_data *i2cs = user_data;
+	struct xt_counters *counters;
+	struct nft_rule_expr *e;
 
-	offset = nft_rule_expr_get_u32(e, NFT_EXPR_PAYLOAD_OFFSET);
+	e = nft_trans_instruction_context_get_expr(first);
 
-	ops->parse_payload(iter, cs, offset);
-}
+	if (!nft_rule_expr_is_set(e, NFT_EXPR_CTR_PACKETS) ||
+				!nft_rule_expr_is_set(e, NFT_EXPR_CTR_BYTES))
+		return -1;
 
-static void
-nft_parse_counter(struct nft_rule_expr *e, struct nft_rule_expr_iter *iter,
-		  struct xt_counters *counters)
-{
+	counters = &i2cs->cs->counters;
 	counters->pcnt = nft_rule_expr_get_u64(e, NFT_EXPR_CTR_PACKETS);
 	counters->bcnt = nft_rule_expr_get_u64(e, NFT_EXPR_CTR_BYTES);
+
+	return 0;
 }
 
-static void
-nft_parse_immediate(struct nft_rule_expr *e, struct nft_rule_expr_iter *iter,
-		    int family, struct iptables_command_state *cs)
+static int
+nft_parse_verdict(struct nft_trans_rule_context *rule_ctx,
+		  struct nft_trans_instruction_context *first,
+		  struct nft_trans_instruction_context *useless,
+		  nft_trans_parse_callback_f user_cb,
+		  void *user_data)
 {
-	int verdict = nft_rule_expr_get_u32(e, NFT_EXPR_IMM_VERDICT);
-	const char *chain = nft_rule_expr_get_str(e, NFT_EXPR_IMM_CHAIN);
+	struct nft_to_cs_data *i2cs = user_data;
 	struct nft_family_ops *ops;
+	struct nft_rule_expr *e;
+	const char *chain;
+	int verdict;
+
+	e = nft_trans_instruction_context_get_expr(first);
+	if (!nft_rule_expr_is_set(e, NFT_EXPR_IMM_VERDICT))
+		return -1;
 
+	verdict = nft_rule_expr_get_u32(e, NFT_EXPR_IMM_VERDICT);
 	/* Standard target? */
 	switch(verdict) {
 	case NF_ACCEPT:
-		cs->jumpto = "ACCEPT";
-		return;
+		i2cs->cs->jumpto = "ACCEPT";
+		break;
 	case NF_DROP:
-		cs->jumpto = "DROP";
-		return;
+		i2cs->cs->jumpto = "DROP";
+		break;
 	case NFT_RETURN:
-		cs->jumpto = "RETURN";
-		return;
+		i2cs->cs->jumpto = "RETURN";
+		break;
 	case NFT_GOTO:
-		ops = nft_family_ops_lookup(family);
-		ops->parse_immediate(cs);
+		ops = nft_family_ops_lookup(i2cs->family);
+		ops->parse_immediate(i2cs->cs);
 	case NFT_JUMP:
-		cs->jumpto = chain;
-		return;
+		if (!nft_rule_expr_is_set(e, NFT_EXPR_IMM_CHAIN))
+			return -1;
+
+		chain = nft_rule_expr_get_str(e, NFT_EXPR_IMM_CHAIN);
+		i2cs->cs->jumpto = chain;
+		break;
 	}
+
+	return 0;
 }
 
-void nft_rule_to_iptables_command_state(struct nft_rule *r,
-					struct iptables_command_state *cs)
+static int nft_parse_io_ifs(struct nft_trans_rule_context *rule_ctx,
+			    struct nft_trans_instruction_context *first,
+			    struct nft_trans_instruction_context *second,
+			    nft_trans_parse_callback_f user_cb,
+			    void *user_data)
 {
-	struct nft_rule_expr_iter *iter;
-	struct nft_rule_expr *expr;
-	int family = nft_rule_attr_get_u8(r, NFT_RULE_ATTR_FAMILY);
+	struct nft_to_cs_data *i2cs = user_data;
+	struct nft_family_ops *ops;
+	struct nft_rule_expr *e;
+	uint8_t key;
 
-	iter = nft_rule_expr_iter_create(r);
-	if (iter == NULL)
-		return;
+	e = nft_trans_instruction_context_get_expr(first);
+	if (!nft_rule_expr_is_set(e, NFT_EXPR_META_KEY))
+		return -1;
 
-	expr = nft_rule_expr_iter_next(iter);
-	while (expr != NULL) {
-		const char *name =
-			nft_rule_expr_get_str(expr, NFT_RULE_EXPR_ATTR_NAME);
+	key = nft_rule_expr_get_u8(e, NFT_EXPR_META_KEY);
+	ops = nft_family_ops_lookup(i2cs->family);
 
-		if (strcmp(name, "counter") == 0) {
-			nft_parse_counter(expr, iter, &cs->counters);
-		} else if (strcmp(name, "payload") == 0) {
-			nft_parse_payload(expr, iter, family, cs);
-		} else if (strcmp(name, "meta") == 0) {
-			nft_parse_meta(expr, iter, family, cs);
-		} else if (strcmp(name, "immediate") == 0) {
-			nft_parse_immediate(expr, iter, family, cs);
-		}
+	e = nft_trans_instruction_context_get_expr(second);
+	ops->parse_meta(e, key, i2cs->cs);
 
-		expr = nft_rule_expr_iter_next(iter);
-	}
+	return 0;
+}
 
-	nft_rule_expr_iter_destroy(iter);
+static int nft_parse_ip_addresses(struct nft_trans_rule_context *rule_ctx,
+				  struct nft_trans_instruction_context *first,
+				  struct nft_trans_instruction_context *last,
+				  nft_trans_parse_callback_f user_cb,
+				  void *user_data)
+{
+	struct nft_to_cs_data *i2cs = user_data;
+	struct nft_rule_expr *e1, *e2;
+	struct nft_family_ops *ops;
+	uint32_t offset;
+
+	e1 = nft_trans_instruction_context_get_expr(first);
+	if (!nft_rule_expr_is_set(e1, NFT_EXPR_PAYLOAD_OFFSET))
+		return -1;
+
+	offset = nft_rule_expr_get_u32(e1, NFT_EXPR_PAYLOAD_OFFSET);
+	ops = nft_family_ops_lookup(i2cs->family);
+
+	first = nft_trans_instruction_context_get_next(first);
+	e1 = nft_trans_instruction_context_get_expr(first);
+	e2 = nft_trans_instruction_context_get_expr(last);
+
+	ops->parse_payload(e1, e2, i2cs->cs, offset);
+
+	return 0;
+}
+
+void nft_rule_to_iptables_command_state(struct nft_rule *r,
+					struct iptables_command_state *cs)
+{
+	struct nft_to_cs_data i2cs = {};
+
+	i2cs.family = nft_rule_attr_get_u8(r, NFT_RULE_ATTR_FAMILY);
+	i2cs.cs = cs;
+
+	nft_trans_rule_translate_to_instructions(xt_nft_tree, r, NULL, &i2cs);
+
+	if (i2cs.cs->target != NULL)
+		i2cs.cs->jumpto = i2cs.cs->target->name;
+	else if (i2cs.cs->jumpto != NULL)
+		i2cs.cs->target = xtables_find_target(i2cs.cs->jumpto,
+							XTF_TRY_LOAD);
+	else
+		i2cs.cs->jumpto = "";
 }
 
 static void
@@ -646,6 +692,71 @@  void print_firewall_details(const struct iptables_command_state *cs,
 	}
 }
 
+static enum nft_instruction nft_ipt_counters_instructions[] = {
+	NFT_INSTRUCTION_COUNTER,
+	NFT_INSTRUCTION_MAX,
+};
+
+static struct nft_trans_instruction nft_ipt_counters = {
+	.instructions = nft_ipt_counters_instructions,
+	.function = nft_parse_counters,
+};
+
+static enum nft_instruction nft_ipt_verdict_instructions[] = {
+	NFT_INSTRUCTION_IMMEDIATE,
+	NFT_INSTRUCTION_MAX,
+};
+
+static struct nft_trans_instruction nft_ipt_verdict = {
+	.instructions = nft_ipt_verdict_instructions,
+	.function = nft_parse_verdict,
+};
+
+static enum nft_instruction nft_ipt_io_ifs_instructions[] = {
+	NFT_INSTRUCTION_META, NFT_INSTRUCTION_CMP,
+	NFT_INSTRUCTION_MAX,
+};
+
+static struct nft_trans_instruction nft_ipt_io_ifs = {
+	.instructions = nft_ipt_io_ifs_instructions,
+	.function = nft_parse_io_ifs,
+};
+
+static enum nft_instruction nft_ipt_ip_addr_instructions_1[] = {
+	NFT_INSTRUCTION_PAYLOAD, NFT_INSTRUCTION_CMP,
+	NFT_INSTRUCTION_MAX,
+};
+
+static struct nft_trans_instruction nft_ipt_ip_addr_1 = {
+	.instructions = nft_ipt_ip_addr_instructions_1,
+	.function = nft_parse_ip_addresses,
+};
+
+static enum nft_instruction nft_ipt_ip_addr_instructions_2[] = {
+	NFT_INSTRUCTION_PAYLOAD, NFT_INSTRUCTION_BITWISE, NFT_INSTRUCTION_CMP,
+	NFT_INSTRUCTION_MAX,
+};
+
+static struct nft_trans_instruction nft_ipt_ip_addr_2 = {
+	.instructions = nft_ipt_ip_addr_instructions_2,
+	.function = nft_parse_ip_addresses,
+};
+
+int nft_initiate_translation_tree(void)
+{
+	xt_nft_tree = nft_trans_instruction_tree_new();
+	if (xt_nft_tree == NULL)
+		return -1;
+
+	nft_trans_add_instruction(xt_nft_tree, &nft_ipt_counters);
+	nft_trans_add_instruction(xt_nft_tree, &nft_ipt_verdict);
+	nft_trans_add_instruction(xt_nft_tree, &nft_ipt_io_ifs);
+	nft_trans_add_instruction(xt_nft_tree, &nft_ipt_ip_addr_1);
+	nft_trans_add_instruction(xt_nft_tree, &nft_ipt_ip_addr_2);
+
+	return 0;
+}
+
 struct nft_family_ops *nft_family_ops_lookup(int family)
 {
 	switch (family) {
diff --git a/iptables/nft-shared.h b/iptables/nft-shared.h
index 488ed63..176abed 100644
--- a/iptables/nft-shared.h
+++ b/iptables/nft-shared.h
@@ -6,6 +6,8 @@ 
 #include <libnftables/rule.h>
 #include <libnftables/expr.h>
 
+#include <nft-translator.h>
+
 #include "xshared.h"
 
 #if 0
@@ -34,6 +36,8 @@ 
 			| FMT_NUMERIC | FMT_NOTABLE)
 #define FMT(tab,notab) ((format) & FMT_NOTABLE ? (notab) : (tab))
 
+extern struct nft_trans_instruction_tree *xt_nft_tree;
+
 struct xtables_args;
 
 struct nft_family_ops {
@@ -44,7 +48,8 @@  struct nft_family_ops {
 			      struct nft_rule_expr_iter *iter);
 	void (*parse_meta)(struct nft_rule_expr *e, uint8_t key,
 			   struct iptables_command_state *cs);
-	void (*parse_payload)(struct nft_rule_expr_iter *iter,
+	void (*parse_payload)(struct nft_rule_expr *e_1,
+			      struct nft_rule_expr *e_2,
 			      struct iptables_command_state *cs,
 			      uint32_t offset);
 	void (*parse_immediate)(struct iptables_command_state *cs);
@@ -82,6 +87,8 @@  void parse_meta(struct nft_rule_expr *e, uint8_t key, char *iniface,
 const char *nft_parse_target(struct nft_rule *r, const void **targinfo,
 			     size_t *target_len);
 void print_proto(uint16_t proto, int invert);
+void get_expr_cmp_data(struct nft_rule_expr *e,
+		       void *data, size_t dlen, bool *inv);
 void get_cmp_data(struct nft_rule_expr_iter *iter,
 		  void *data, size_t dlen, bool *inv);
 void nft_rule_to_iptables_command_state(struct nft_rule *r,
@@ -95,7 +102,7 @@  void print_firewall_details(const struct iptables_command_state *cs,
 			    uint8_t invflags, uint8_t proto,
 			    const char *iniface, const char *outiface,
 			    unsigned int num, unsigned int format);
-
+int nft_initiate_translation_tree(void);
 struct nft_family_ops *nft_family_ops_lookup(int family);
 
 struct addr_mask {
@@ -126,6 +133,11 @@  struct xtables_args {
 	unsigned long long pcnt_cnt, bcnt_cnt;
 };
 
+struct nft_to_cs_data {
+	int family;
+	struct iptables_command_state *cs;
+};
+
 #define CMD_NONE		0x0000U
 #define CMD_INSERT		0x0001U
 #define CMD_DELETE		0x0002U
diff --git a/iptables/nft.c b/iptables/nft.c
index d92e8bb..7171752 100644
--- a/iptables/nft.c
+++ b/iptables/nft.c
@@ -388,6 +388,9 @@  int nft_init(struct nft_handle *h, struct builtin_table *t)
 	h->portid = mnl_socket_get_portid(h->nl);
 	h->tables = t;
 
+	if (nft_initiate_translation_tree() != 0)
+		return -1;
+
 	return 0;
 }