diff options
| -rw-r--r-- | src/payload.c | 29 |
1 files changed, 26 insertions, 3 deletions
diff --git a/src/payload.c b/src/payload.c index a77ca550..cfa95224 100644 --- a/src/payload.c +++ b/src/payload.c @@ -661,6 +661,24 @@ static bool payload_may_dependency_kill_icmp(struct payload_dep_ctx *ctx, struct return ctx->icmp_type == icmp_type; } +static bool payload_may_dependency_kill_ll(struct payload_dep_ctx *ctx, struct expr *expr) +{ + const struct expr *dep = ctx->pdep->expr; + + /* Never remove a 'vlan type 0x...' expression, they are never added implicitly */ + if (dep->left->payload.desc == &proto_vlan) + return false; + + /* 'vlan id 2' implies 'ether type 8021Q'. If a different protocol is + * tested, this is not a redundant expression. + */ + if (dep->left->payload.desc == &proto_eth && + dep->right->etype == EXPR_VALUE && dep->right->len == 16) + return mpz_get_uint16(dep->right->value) == ETH_P_8021Q; + + return true; +} + static bool payload_may_dependency_kill(struct payload_dep_ctx *ctx, unsigned int family, struct expr *expr) { @@ -689,9 +707,14 @@ static bool payload_may_dependency_kill(struct payload_dep_ctx *ctx, * for stacked protocols if we only have protcol type matches. */ if (dep->left->etype == EXPR_PAYLOAD && dep->op == OP_EQ && - expr->flags & EXPR_F_PROTOCOL && - expr->payload.base == dep->left->payload.base) - return false; + expr->payload.base == dep->left->payload.base) { + if (expr->flags & EXPR_F_PROTOCOL) + return false; + + if (expr->payload.base == PROTO_BASE_LL_HDR) + return payload_may_dependency_kill_ll(ctx, expr); + } + break; } |