diff options
| -rw-r--r-- | include/payload.h | 2 | ||||
| -rw-r--r-- | src/netlink_delinearize.c | 28 | ||||
| -rw-r--r-- | src/payload.c | 20 |
3 files changed, 27 insertions, 23 deletions
diff --git a/include/payload.h b/include/payload.h index eb9ff17d..b180ff53 100644 --- a/include/payload.h +++ b/include/payload.h @@ -30,6 +30,8 @@ struct payload_dep_ctx { struct stmt *prev; }; +extern bool payload_is_stacked(const struct proto_desc *desc, + const struct expr *expr); extern void payload_dependency_store(struct payload_dep_ctx *ctx, struct stmt *stmt, enum proto_bases base); diff --git a/src/netlink_delinearize.c b/src/netlink_delinearize.c index 59e5f3e6..84f94fc3 100644 --- a/src/netlink_delinearize.c +++ b/src/netlink_delinearize.c @@ -1032,27 +1032,6 @@ static void integer_type_postprocess(struct expr *expr) } } -static void payload_dependency_save(struct rule_pp_ctx *ctx, unsigned int base, - struct stmt *nstmt, struct expr *tmp) -{ - unsigned int proto = mpz_get_be16(tmp->value); - const struct proto_desc *desc, *next; - bool stacked_header = false; - - desc = ctx->pctx.protocol[base].desc; - - assert(desc); - if (desc) { - next = proto_find_upper(desc, proto); - stacked_header = next && next->base == base; - } - - if (stacked_header) - payload_dependency_store(&ctx->pdctx, nstmt, base - 1); - else - payload_dependency_store(&ctx->pdctx, nstmt, base); -} - static void payload_match_expand(struct rule_pp_ctx *ctx, struct expr *expr, struct expr *payload) @@ -1063,6 +1042,7 @@ static void payload_match_expand(struct rule_pp_ctx *ctx, struct expr *nexpr = NULL; enum proto_bases base = left->payload.base; const struct expr_ops *payload_ops = left->ops; + bool stacked; payload_expr_expand(&list, left, &ctx->pctx); @@ -1084,6 +1064,8 @@ static void payload_match_expand(struct rule_pp_ctx *ctx, assert(left->payload.base); assert(base == left->payload.base); + stacked = payload_is_stacked(ctx->pctx.protocol[base].desc, nexpr); + /* Remember the first payload protocol expression to * kill it later on if made redundant by a higher layer * payload expression. @@ -1091,11 +1073,11 @@ static void payload_match_expand(struct rule_pp_ctx *ctx, if (ctx->pdctx.pbase == PROTO_BASE_INVALID && expr->op == OP_EQ && left->flags & EXPR_F_PROTOCOL) { - payload_dependency_save(ctx, base, nstmt, tmp); + payload_dependency_store(&ctx->pdctx, nstmt, base - stacked); } else { payload_dependency_kill(&ctx->pdctx, nexpr->left); if (left->flags & EXPR_F_PROTOCOL) - payload_dependency_save(ctx, base, nstmt, tmp); + payload_dependency_store(&ctx->pdctx, nstmt, base - stacked); } } list_del(&ctx->stmt->list); diff --git a/src/payload.c b/src/payload.c index 9dca56be..0bbfb542 100644 --- a/src/payload.c +++ b/src/payload.c @@ -322,6 +322,26 @@ int exthdr_gen_dependency(struct eval_ctx *ctx, const struct expr *expr, } /** + * payload_is_stacked - return whether a payload protocol match defines a stacked + * protocol on the same layer + * + * @desc: current protocol description on this layer + * @expr: payload match + */ +bool payload_is_stacked(const struct proto_desc *desc, const struct expr *expr) +{ + const struct proto_desc *next; + + if (expr->left->ops->type != EXPR_PAYLOAD || + !(expr->left->flags & EXPR_F_PROTOCOL) || + expr->op != OP_EQ) + return false; + + next = proto_find_upper(desc, mpz_get_be16(expr->right->value)); + return next && next->base == desc->base; +} + +/** * payload_dependency_store - store a possibly redundant protocol match * * @ctx: payload dependency context |