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src: add offset attribute for hash expression

PATCH Applied Laura Garcia Liebana 2 participants 2 messages Nov 4, 2016 – Nov 8, 2016 netfilter

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Laura Garcia Liebana

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#0 lore raw

PATCH v3 2/4 src: add offset attribute for hash expression

Add support to add an offset to the hash generator, eg.

ct mark set hash ip saddr mod 10 offset 100

This will generate marks with series between 100-109.

Signed-off-by Laura Garcia Liebana <[email protected]>

---
Changes in v3:
- This patch depends on 1/4.

 include/expression.h                |  1 +
 include/hash.h                      |  3 ++-
 include/linux/netfilter/nf_tables.h |  2 ++
 src/hash.c                          |  9 +++++++--
 src/netlink_delinearize.c           |  5 +++--
 src/netlink_linearize.c             |  1 +
 src/parser_bison.y                  |  8 ++++----
 tests/py/ip/hash.t                  |  2 ++
 tests/py/ip/hash.t.payload          | 14 ++++++++++++++
 9 files changed, 36 insertions(+), 9 deletions(-)
include/expression.h +1 -0
index 3a52a45..71e9c43 100644
@@ -307,6 +307,7 @@ struct expr {
 			struct expr		*expr;
 			uint32_t		mod;
 			uint32_t		seed;
+			uint32_t		offset;
 		} hash;
 		struct {
 			/* EXPR_FIB */
include/hash.h +2 -1
index bc8c86a..8bf53e2 100644
@@ -2,6 +2,7 @@
 #define NFTABLES_HASH_H
 
 extern struct expr *hash_expr_alloc(const struct location *loc,
-				    uint32_t modulus, uint32_t seed);
+				    uint32_t modulus, uint32_t seed,
+				    uint32_t offset);
 
 #endif /* NFTABLES_HASH_H */
include/linux/netfilter/nf_tables.h +2 -0
index c6567ac..0fb63fe 100644
@@ -773,6 +773,7 @@ enum nft_rt_keys {
  * @NFTA_HASH_LEN: source data length (NLA_U32)
  * @NFTA_HASH_MODULUS: modulus value (NLA_U32)
  * @NFTA_HASH_SEED: seed value (NLA_U32)
+ * @NFTA_HASH_OFFSET: offset value (NLA_U32)
  */
 enum nft_hash_attributes {
 	NFTA_HASH_UNSPEC,

@@ -781,6 +782,7 @@ enum nft_hash_attributes {
 	NFTA_HASH_LEN,
 	NFTA_HASH_MODULUS,
 	NFTA_HASH_SEED,
+	NFTA_HASH_OFFSET,
 	__NFTA_HASH_MAX,
 };
 #define NFTA_HASH_MAX	(__NFTA_HASH_MAX - 1)
src/hash.c +7 -2
index 125b320..d26b2ed 100644
@@ -22,13 +22,16 @@ static void hash_expr_print(const struct expr *expr)
 	printf(" mod %u", expr->hash.mod);
 	if (expr->hash.seed)
 		printf(" seed 0x%x", expr->hash.seed);
+	if (expr->hash.offset)
+		printf(" offset %u", expr->hash.offset);
 }
 
 static bool hash_expr_cmp(const struct expr *e1, const struct expr *e2)
 {
 	return expr_cmp(e1->hash.expr, e2->hash.expr) &&
 	       e1->hash.mod == e2->hash.mod &&
-	       e1->hash.seed == e2->hash.seed;
+	       e1->hash.seed == e2->hash.seed &&
+	       e1->hash.offset == e2->hash.offset;
 }
 
 static void hash_expr_clone(struct expr *new, const struct expr *expr)

@@ -36,6 +39,7 @@ static void hash_expr_clone(struct expr *new, const struct expr *expr)
 	new->hash.expr = expr_clone(expr->hash.expr);
 	new->hash.mod = expr->hash.mod;
 	new->hash.seed = expr->hash.seed;
+	new->hash.offset = expr->hash.offset;
 }
 
 static const struct expr_ops hash_expr_ops = {

@@ -47,7 +51,7 @@ static const struct expr_ops hash_expr_ops = {
 };
 
 struct expr *hash_expr_alloc(const struct location *loc, uint32_t mod,
-			     uint32_t seed)
+			     uint32_t seed, uint32_t offset)
 {
 	struct expr *expr;
 

@@ -55,6 +59,7 @@ struct expr *hash_expr_alloc(const struct location *loc, uint32_t mod,
 			  BYTEORDER_HOST_ENDIAN, 4 * BITS_PER_BYTE);
 	expr->hash.mod  = mod;
 	expr->hash.seed = seed;
+	expr->hash.offset = offset;
 
 	return expr;
 }
src/netlink_delinearize.c +3 -2
index f0df884..434089b 100644
@@ -513,7 +513,7 @@ static void netlink_parse_hash(struct netlink_parse_ctx *ctx,
 {
 	enum nft_registers sreg, dreg;
 	struct expr *expr, *hexpr;
-	uint32_t mod, seed, len;
+	uint32_t mod, seed, len, offset;
 
 	sreg = netlink_parse_register(nle, NFTNL_EXPR_HASH_SREG);
 	hexpr = netlink_get_register(ctx, loc, sreg);

@@ -521,6 +521,7 @@ static void netlink_parse_hash(struct netlink_parse_ctx *ctx,
 		return netlink_error(ctx, loc,
 				     "hash statement has no expression");
 
+	offset = nftnl_expr_get_u32(nle, NFTNL_EXPR_HASH_OFFSET);
 	seed = nftnl_expr_get_u32(nle, NFTNL_EXPR_HASH_SEED);
 	mod  = nftnl_expr_get_u32(nle, NFTNL_EXPR_HASH_MODULUS);
 	len = nftnl_expr_get_u32(nle, NFTNL_EXPR_HASH_LEN) * BITS_PER_BYTE;

@@ -531,7 +532,7 @@ static void netlink_parse_hash(struct netlink_parse_ctx *ctx,
 			return;
 	}
 
-	expr = hash_expr_alloc(loc, mod, seed);
+	expr = hash_expr_alloc(loc, mod, seed, offset);
 	expr->hash.expr = hexpr;
 
 	dreg = netlink_parse_register(nle, NFTNL_EXPR_HASH_DREG);
src/netlink_linearize.c +1 -0
index 0458af9..6c0f39b 100644
@@ -136,6 +136,7 @@ static void netlink_gen_hash(struct netlink_linearize_ctx *ctx,
 			   div_round_up(expr->hash.expr->len, BITS_PER_BYTE));
 	nftnl_expr_set_u32(nle, NFTNL_EXPR_HASH_MODULUS, expr->hash.mod);
 	nftnl_expr_set_u32(nle, NFTNL_EXPR_HASH_SEED, expr->hash.seed);
+	nftnl_expr_set_u32(nle, NFTNL_EXPR_HASH_OFFSET, expr->hash.offset);
 	nftnl_rule_add_expr(ctx->nlr, nle);
 }
src/parser_bison.y +4 -4
index 82fec99..74f24a5 100644
@@ -2580,14 +2580,14 @@ numgen_expr		:	NUMGEN	numgen_type	MOD	NUM	offset_opt
 			}
 			;
 
-hash_expr		:	JHASH	expr	MOD	NUM	SEED	NUM
+hash_expr		:	JHASH	expr	MOD	NUM	SEED	NUM	offset_opt
 			{
-				$$ = hash_expr_alloc(&@$, $4, $6);
+				$$ = hash_expr_alloc(&@$, $4, $6, $7);
 				$$->hash.expr = $2;
 			}
-			|	JHASH	expr	MOD	NUM
+			|	JHASH	expr	MOD	NUM	offset_opt
 			{
-				$$ = hash_expr_alloc(&@$, $4, 0);
+				$$ = hash_expr_alloc(&@$, $4, 0, $5);
 				$$->hash.expr = $2;
 			}
 			;
tests/py/ip/hash.t +2 -0
index 306ebfd..0d01a11 100644
@@ -3,4 +3,6 @@
 
 ct mark set jhash ip saddr . ip daddr mod 2 seed 0xdeadbeef;ok
 ct mark set jhash ip saddr . ip daddr mod 2;ok
+ct mark set jhash ip saddr . ip daddr mod 2 seed 0xdeadbeef offset 100;ok
+ct mark set jhash ip saddr . ip daddr mod 2 offset 100;ok
 dnat to jhash ip saddr mod 2 seed 0xdeadbeef map { 0 : 192.168.20.100, 1 : 192.168.30.100 };ok
tests/py/ip/hash.t.payload +14 -0
index 1188a1b..c410a8c 100644
@@ -12,6 +12,20 @@ ip test-ip4 pre
   [ hash reg 1 = jhash(reg 2, 8, 0x0) % mod 2 ]
   [ ct set mark with reg 1 ]
 
+# ct mark set jhash ip saddr . ip daddr mod 2 seed 0xdeadbeef offset 100
+ip test-ip4 pre
+  [ payload load 4b @ network header + 12 => reg 2 ]
+  [ payload load 4b @ network header + 16 => reg 13 ]
+  [ hash reg 1 = jhash(reg 2, 8, 0xdeadbeef) % mod 2 offset 100 ]
+  [ ct set mark with reg 1 ]
+
+# ct mark set jhash ip saddr . ip daddr mod 2 offset 100
+ip test-ip4 pre
+  [ payload load 4b @ network header + 12 => reg 2 ]
+  [ payload load 4b @ network header + 16 => reg 13 ]
+  [ hash reg 1 = jhash(reg 2, 8, 0x0) % mod 2 offset 100 ]
+  [ ct set mark with reg 1 ]
+
 # dnat to jhash ip saddr mod 2 seed 0xdeadbeef map { 0 : 192.168.20.100, 1 : 192.168.30.100 }
 __map%d test-ip4 b
 __map%d test-ip4 0
Signature · 1 line
2.9.3
maintainer
#1 lore raw
Quoted 5 lines · Laura Garcia Liebana

Add support to add an offset to the hash generator, eg.

ct mark set hash ip saddr mod 10 offset 100

This will generate marks with series between 100-109.

Also applied, thanks.