src: allow use of base integer types as set keys in concatenations

"typeof ip saddr . ipsec in reqid" won't work because reqid uses
integer type, i.e. dtype->size is 0.

With "typeof", the size can be derived from the expression length,
via set->key.

This computes the concat length based either on dtype->size or
expression length.

It also updates concat evaluation to permit a zero datatype size
if the subkey expression has nonzero length (i.e., typeof was used).

Signed-off-by: Florian Westphal <fw@strlen.de>

diff --git a/src/evaluate.c b/src/evaluate.c
index 503b4f0366555add8d2d7bd2d2688001ab69cfb5..b5f74d2f505162ab878fbf78fe31c7edf282a623 100644 (file)
--- a/src/evaluate.c
+++ b/src/evaluate.c
@@ -1270,7 +1270,8 @@ static int expr_evaluate_concat(struct eval_ctx *ctx, struct expr **expr)
        }
 
        list_for_each_entry_safe(i, next, &(*expr)->expressions, list) {
-               unsigned dsize_bytes;
+               enum byteorder bo = BYTEORDER_INVALID;
+               unsigned dsize_bytes, dsize = 0;
 
                if (i->etype == EXPR_CT &&
                    (i->ct.key == NFT_CT_SRC ||
@@ -1286,14 +1287,18 @@ static int expr_evaluate_concat(struct eval_ctx *ctx, struct expr **expr)
 
                if (key) {
                        tmp = key->dtype;
+                       dsize = key->len;
+                       bo = key->byteorder;
                        off--;
                } else if (dtype == NULL) {
                        tmp = datatype_lookup(TYPE_INVALID);
                } else {
                        tmp = concat_subtype_lookup(type, --off);
+                       dsize = tmp->size;
+                       bo = tmp->byteorder;
                }
 
-               expr_set_context(&ctx->ectx, tmp, tmp->size);
+               __expr_set_context(&ctx->ectx, tmp, bo, dsize, 0);
 
                if (list_member_evaluate(ctx, &i) < 0)
                        return -1;
@@ -1315,12 +1320,14 @@ static int expr_evaluate_concat(struct eval_ctx *ctx, struct expr **expr)
                                                 "data types (%s) in concat "
                                                 "expressions",
                                                 i->dtype->name);
+               if (dsize == 0) /* reload after evaluation or clone above */
+                       dsize = i->dtype->size;
 
                ntype = concat_subtype_add(ntype, i->dtype->type);
 
-               dsize_bytes = div_round_up(i->dtype->size, BITS_PER_BYTE);
+               dsize_bytes = div_round_up(dsize, BITS_PER_BYTE);
                (*expr)->field_len[(*expr)->field_count++] = dsize_bytes;
-               size += netlink_padded_len(i->dtype->size);
+               size += netlink_padded_len(dsize);
                if (key)
                        key = list_next_entry(key, list);
        }
@@ -4046,20 +4053,23 @@ static int set_expr_evaluate_concat(struct eval_ctx *ctx, struct expr **expr)
                        i->dtype = dtype;
                }
 
-               if (i->dtype->size == 0)
+               if (i->dtype->size == 0 && i->len == 0)
                        return expr_binary_error(ctx->msgs, i, *expr,
                                                 "can not use variable sized "
                                                 "data types (%s) in concat "
                                                 "expressions",
                                                 i->dtype->name);
 
+               if (i->dtype->size)
+                       assert(i->len == i->dtype->size);
+
                flags &= i->flags;
 
                ntype = concat_subtype_add(ntype, i->dtype->type);
 
-               dsize_bytes = div_round_up(i->dtype->size, BITS_PER_BYTE);
+               dsize_bytes = div_round_up(i->len, BITS_PER_BYTE);
                (*expr)->field_len[(*expr)->field_count++] = dsize_bytes;
-               size += netlink_padded_len(i->dtype->size);
+               size += netlink_padded_len(i->len);
        }
 
        (*expr)->flags |= flags;