From 5e393ea1fc0ad6b59e90103bf83e93b2449d519e Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Sat, 9 Apr 2022 15:58:29 +0200 Subject: segtree: add string "range" reversal support Previous commits allows to use set key as a range, i.e. key ifname flags interval elements = { eth* } and then have it match on any interface starting with 'eth'. Listing is broken however, we need to reverse-translate the (128bit) number back to a string. 'eth*' is stored as interval 00687465 0000000 .. 00697465 0000000, i.e. "eth-eti", this adds the needed endianess fixups. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- src/segtree.c | 47 +++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 41 insertions(+), 6 deletions(-) diff --git a/src/segtree.c b/src/segtree.c index b4e76bf5..bed8bbcf 100644 --- a/src/segtree.c +++ b/src/segtree.c @@ -1032,6 +1032,33 @@ static struct expr *interval_to_prefix(struct expr *low, struct expr *i, const m return __expr_to_set_elem(low, prefix); } +static struct expr *interval_to_string(struct expr *low, struct expr *i, const mpz_t range) +{ + unsigned int len = div_round_up(i->len, BITS_PER_BYTE); + unsigned int prefix_len, str_len; + char data[len + 2]; + struct expr *expr; + + prefix_len = expr_value(i)->len - mpz_scan0(range, 0); + + if (prefix_len > i->len || prefix_len % BITS_PER_BYTE) + return interval_to_prefix(low, i, range); + + mpz_export_data(data, expr_value(low)->value, BYTEORDER_BIG_ENDIAN, len); + + str_len = strnlen(data, len); + if (str_len >= len || str_len == 0) + return interval_to_prefix(low, i, range); + + data[str_len] = '*'; + + expr = constant_expr_alloc(&low->location, low->dtype, + BYTEORDER_HOST_ENDIAN, + (str_len + 1) * BITS_PER_BYTE, data); + + return __expr_to_set_elem(low, expr); +} + static struct expr *interval_to_range(struct expr *low, struct expr *i, mpz_t range) { struct expr *tmp; @@ -1130,16 +1157,24 @@ void interval_map_decompose(struct expr *set) mpz_and(p, expr_value(low)->value, range); - if (!mpz_cmp_ui(range, 0)) + if (!mpz_cmp_ui(range, 0)) { + if (expr_basetype(low)->type == TYPE_STRING) + mpz_switch_byteorder(expr_value(low)->value, low->len / BITS_PER_BYTE); + compound_expr_add(set, expr_get(low)); - else if ((!range_is_prefix(range) || - !(i->dtype->flags & DTYPE_F_PREFIX)) || - mpz_cmp_ui(p, 0)) { - struct expr *expr = interval_to_range(low, i, range); + } else if (range_is_prefix(range) && !mpz_cmp_ui(p, 0)) { + struct expr *expr; + + if (i->dtype->flags & DTYPE_F_PREFIX) + expr = interval_to_prefix(low, i, range); + else if (expr_basetype(i)->type == TYPE_STRING) + expr = interval_to_string(low, i, range); + else + expr = interval_to_range(low, i, range); compound_expr_add(set, expr); } else { - struct expr *expr = interval_to_prefix(low, i, range); + struct expr *expr = interval_to_range(low, i, range); compound_expr_add(set, expr); } -- cgit v1.2.3