diff options
author | Florian Westphal <fw@strlen.de> | 2016-03-02 13:56:43 +0100 |
---|---|---|
committer | Florian Westphal <fw@strlen.de> | 2016-03-02 13:56:43 +0100 |
commit | 85bbbe8c4dc9c9aec28d6648a928f0946a14c994 (patch) | |
tree | 8ef2e1c3fc49b94cf67b525f1d3e24f0f3fa9c5c /src/netlink_linearize.c | |
parent | d63da0cc9620ae4a274fb006f0ca01e1e0ecf4f2 (diff) |
netlink: split generic part of netlink_gen_payload_mask into helper
netlink_gen_payload_mask assumes expr is a payload expression,
but most of this function would work fine with exthdr too.
So split the gernic part into a helper, followup patch will
add netlink_gen_exthdr_mask.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'src/netlink_linearize.c')
-rw-r--r-- | src/netlink_linearize.c | 35 |
1 files changed, 23 insertions, 12 deletions
diff --git a/src/netlink_linearize.c b/src/netlink_linearize.c index 86b49c64..7715a287 100644 --- a/src/netlink_linearize.c +++ b/src/netlink_linearize.c @@ -103,12 +103,13 @@ static void netlink_gen_concat(struct netlink_linearize_ctx *ctx, } } -static unsigned int payload_shift_calc(const struct expr *expr) +static unsigned int payload_shift_calc(const struct expr *expr, + unsigned int offset) { - unsigned int offset, len; + unsigned int len; int shift; - offset = expr->payload.offset % BITS_PER_BYTE; + offset %= BITS_PER_BYTE; len = round_up(expr->len, BITS_PER_BYTE); shift = len - (offset + expr->len); assert(shift >= 0); @@ -116,19 +117,16 @@ static unsigned int payload_shift_calc(const struct expr *expr) return shift; } -static void netlink_gen_payload_mask(struct netlink_linearize_ctx *ctx, - const struct expr *expr, - enum nft_registers dreg) +static void netlink_gen_mask(struct netlink_linearize_ctx *ctx, + const struct expr *expr, + unsigned int shift, + enum nft_registers dreg) { struct nft_data_linearize nld, zero = {}; - unsigned int shift, len, masklen; + unsigned int len, masklen; struct nftnl_expr *nle; mpz_t mask; - shift = payload_shift_calc(expr); - if (!shift && expr->payload.offset % BITS_PER_BYTE == 0) - return; - masklen = expr->len + shift; assert(masklen <= NFT_REG_SIZE * BITS_PER_BYTE); mpz_init2(mask, masklen); @@ -151,6 +149,18 @@ static void netlink_gen_payload_mask(struct netlink_linearize_ctx *ctx, nftnl_rule_add_expr(ctx->nlr, nle); } +static void netlink_gen_payload_mask(struct netlink_linearize_ctx *ctx, + const struct expr *expr, + enum nft_registers dreg) +{ + unsigned int shift, offset; + + offset = expr->payload.offset % BITS_PER_BYTE; + shift = payload_shift_calc(expr, offset); + if (shift || offset) + netlink_gen_mask(ctx, expr, shift, dreg); +} + static void netlink_gen_payload(struct netlink_linearize_ctx *ctx, const struct expr *expr, enum nft_registers dreg) @@ -300,7 +310,8 @@ static void payload_shift_value(const struct expr *left, struct expr *right) left->ops->type != EXPR_PAYLOAD) return; - mpz_lshift_ui(right->value, payload_shift_calc(left)); + mpz_lshift_ui(right->value, + payload_shift_calc(left, left->payload.offset)); } static struct expr *netlink_gen_prefix(struct netlink_linearize_ctx *ctx, |