[nft PATCH 1/2] src: fix byteorder conversions

[Alvaro Neira Ayuso <alvaroneay@gmail.com>]

Currently the byteorder conversion happens in the parser,
the evaluation and the code generation steps. This is a problem
because the expression which are already in big endian byteorder
are converted again.

With this patch, we don't change byteorder in the code generation
step anymore because we assume that all expressions are in the
appropriate byteorder. This patch solves rules like:

nft add rule bridge filter input ether type ip

With this rule we create a expression like:

[ payload load 2b @ link header + 12 => reg 1 ]
  [ cmp eq reg 1 0x00000800 ]

With this patch, we have a expresion with the correct conversion:

[ payload load 2b @ link header + 12 => reg 1 ]
  [ cmp eq reg 1 0x00000008 ]

This is also a problem in the delinearize step because the expression
are already converted to the correctly byteorder and we change it again.

Signed-off-by: Alvaro Neira Ayuso <alvaroneay@gmail.com>
---
 include/netlink.h         |    3 +--
 src/datatype.c            |    2 +-
 src/gmputil.c             |    2 +-
 src/netlink.c             |   11 +++++++----
 src/netlink_delinearize.c |    2 +-
 src/netlink_linearize.c   |   10 +++++-----
 src/payload.c             |    3 +--
 7 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/include/netlink.h b/include/netlink.h
index 4ef7365..1e82fce 100644
--- a/include/netlink.h
+++ b/include/netlink.h
@@ -55,8 +55,7 @@ struct nft_data_delinearize {
 
 extern void netlink_gen_data(const struct expr *expr,
 			     struct nft_data_linearize *data);
-extern void netlink_gen_raw_data(const mpz_t value, enum byteorder byteorder,
-				 unsigned int len,
+extern void netlink_gen_raw_data(const mpz_t value, unsigned int len,
 				 struct nft_data_linearize *data);
 
 extern struct expr *netlink_alloc_value(const struct location *loc,
diff --git a/src/datatype.c b/src/datatype.c
index 55af227..0a3aa41 100644
--- a/src/datatype.c
+++ b/src/datatype.c
@@ -545,7 +545,7 @@ static struct error_record *inet_service_type_parse(const struct expr *sym,
 		if (errno == ERANGE || i > UINT16_MAX)
 			return error(&sym->location, "Service out of range");
 
-		port = htons(i);
+		port = i;
 	} else {
 		err = getaddrinfo(NULL, sym->identifier, NULL, &ai);
 		if (err != 0)
diff --git a/src/gmputil.c b/src/gmputil.c
index cb46445..2e4438a 100644
--- a/src/gmputil.c
+++ b/src/gmputil.c
@@ -127,11 +127,11 @@ void mpz_import_data(mpz_t rop, const void *data,
 
 	switch (byteorder) {
 	case BYTEORDER_BIG_ENDIAN:
-	default:
 		order  = MPZ_MSWF;
 		endian = MPZ_BIG_ENDIAN;
 		break;
 	case BYTEORDER_HOST_ENDIAN:
+	default:
 		order  = MPZ_HWO;
 		endian = MPZ_HOST_ENDIAN;
 		break;
diff --git a/src/netlink.c b/src/netlink.c
index 987dd63..0547fa5 100644
--- a/src/netlink.c
+++ b/src/netlink.c
@@ -234,11 +234,14 @@ static struct nft_set_elem *alloc_nft_setelem(const struct expr *expr)
 	return nlse;
 }
 
-void netlink_gen_raw_data(const mpz_t value, enum byteorder byteorder,
-			  unsigned int len, struct nft_data_linearize *data)
+void netlink_gen_raw_data(const mpz_t value, unsigned int len,
+			  struct nft_data_linearize *data)
 {
 	assert(len > 0);
-	mpz_export_data(data->value, value, byteorder, len);
+	/* Here, we can suppose that all the values has been converted with the
+	 * byteorder and all are in HOST_ENDIAN
+	 */
+	mpz_export_data(data->value, value, BYTEORDER_HOST_ENDIAN, len);
 	data->len = len;
 }
 
@@ -272,7 +275,7 @@ static void netlink_gen_constant_data(const struct expr *expr,
 				      struct nft_data_linearize *data)
 {
 	assert(expr->ops->type == EXPR_VALUE);
-	netlink_gen_raw_data(expr->value, expr->byteorder,
+	netlink_gen_raw_data(expr->value,
 			     div_round_up(expr->len, BITS_PER_BYTE), data);
 }
 
diff --git a/src/netlink_delinearize.c b/src/netlink_delinearize.c
index 5c6ca80..ad74cdb 100644
--- a/src/netlink_delinearize.c
+++ b/src/netlink_delinearize.c
@@ -642,7 +642,7 @@ static void payload_match_postprocess(struct rule_pp_ctx *ctx,
 		list_for_each_entry(left, &list, list) {
 			tmp = constant_expr_splice(right, left->len);
 			expr_set_type(tmp, left->dtype, left->byteorder);
-			if (tmp->byteorder == BYTEORDER_HOST_ENDIAN)
+			if (tmp->byteorder == BYTEORDER_BIG_ENDIAN)
 				mpz_switch_byteorder(tmp->value, tmp->len / BITS_PER_BYTE);
 
 			nexpr = relational_expr_alloc(&expr->location, expr->op,
diff --git a/src/netlink_linearize.c b/src/netlink_linearize.c
index 5c1b46d..8788813 100644
--- a/src/netlink_linearize.c
+++ b/src/netlink_linearize.c
@@ -206,8 +206,8 @@ static void netlink_gen_cmp(struct netlink_linearize_ctx *ctx,
 
 		mpz_init(mask);
 		mpz_prefixmask(mask, expr->right->len, expr->right->prefix_len);
-		netlink_gen_raw_data(mask, expr->right->byteorder,
-				     expr->right->len / BITS_PER_BYTE, &nld);
+		netlink_gen_raw_data(mask, expr->right->len / BITS_PER_BYTE,
+				     &nld);
 		mpz_clear(mask);
 
 		zero.len = nld.len;
@@ -315,7 +315,7 @@ static void netlink_gen_flagcmp(struct netlink_linearize_ctx *ctx,
 
 	mpz_init_set_ui(zero, 0);
 
-	netlink_gen_raw_data(zero, expr->right->byteorder, len, &nld);
+	netlink_gen_raw_data(zero, len, &nld);
 	netlink_gen_data(expr->right, &nld2);
 
 	nle = alloc_nft_expr("bitwise");
@@ -423,9 +423,9 @@ static void netlink_gen_binop(struct netlink_linearize_ctx *ctx,
 	nft_rule_expr_set_u32(nle, NFT_EXPR_BITWISE_DREG, dreg);
 	nft_rule_expr_set_u32(nle, NFT_EXPR_BITWISE_LEN, len);
 
-	netlink_gen_raw_data(mask, expr->byteorder, len, &nld);
+	netlink_gen_raw_data(mask, len, &nld);
 	nft_rule_expr_set(nle, NFT_EXPR_BITWISE_MASK, nld.value, nld.len);
-	netlink_gen_raw_data(xor, expr->byteorder, len, &nld);
+	netlink_gen_raw_data(xor, len, &nld);
 	nft_rule_expr_set(nle, NFT_EXPR_BITWISE_XOR, nld.value, nld.len);
 
 	mpz_clear(tmp);
diff --git a/src/payload.c b/src/payload.c
index a1785a5..432ce44 100644
--- a/src/payload.c
+++ b/src/payload.c
@@ -208,8 +208,7 @@ int payload_gen_dependency(struct eval_ctx *ctx, const struct expr *expr,
 		left = payload_expr_alloc(&expr->location, desc, desc->protocol_key);
 
 	right = constant_expr_alloc(&expr->location, tmpl->dtype,
-				    BYTEORDER_HOST_ENDIAN,
-				    tmpl->len,
+				    tmpl->dtype->byteorder, tmpl->len,
 				    constant_data_ptr(protocol, tmpl->len));
 
 	dep = relational_expr_alloc(&expr->location, OP_EQ, left, right);
-- 
1.7.10.4