diff options
Diffstat (limited to 'src/resolve/resolved-dns-answer.h')
| -rw-r--r-- | src/resolve/resolved-dns-answer.h | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/src/resolve/resolved-dns-answer.h b/src/resolve/resolved-dns-answer.h new file mode 100644 index 0000000..47fc80e --- /dev/null +++ b/src/resolve/resolved-dns-answer.h @@ -0,0 +1,129 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ +#pragma once + +typedef struct DnsAnswer DnsAnswer; +typedef struct DnsAnswerItem DnsAnswerItem; + +#include "macro.h" +#include "resolved-dns-rr.h" + +/* A simple array of resource records. We keep track of the + * originating ifindex for each RR where that makes sense, so that we + * can qualify A and AAAA RRs referring to a local link with the + * right ifindex. + * + * Note that we usually encode the empty DnsAnswer object as a simple NULL. */ + +typedef enum DnsAnswerFlags { + DNS_ANSWER_AUTHENTICATED = 1 << 0, /* Item has been authenticated */ + DNS_ANSWER_CACHEABLE = 1 << 1, /* Item is subject to caching */ + DNS_ANSWER_SHARED_OWNER = 1 << 2, /* For mDNS: RRset may be owner by multiple peers */ + DNS_ANSWER_CACHE_FLUSH = 1 << 3, /* For mDNS: sets cache-flush bit in the rrclass of response records */ + DNS_ANSWER_GOODBYE = 1 << 4, /* For mDNS: item is subject to disappear */ +} DnsAnswerFlags; + +struct DnsAnswerItem { + DnsResourceRecord *rr; + int ifindex; + DnsAnswerFlags flags; +}; + +struct DnsAnswer { + unsigned n_ref; + size_t n_rrs, n_allocated; + DnsAnswerItem items[0]; +}; + +DnsAnswer *dns_answer_new(size_t n); +DnsAnswer *dns_answer_ref(DnsAnswer *a); +DnsAnswer *dns_answer_unref(DnsAnswer *a); + +int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags); +int dns_answer_add_extend(DnsAnswer **a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags); +int dns_answer_add_soa(DnsAnswer *a, const char *name, uint32_t ttl, int ifindex); + +int dns_answer_match_key(DnsAnswer *a, const DnsResourceKey *key, DnsAnswerFlags *combined_flags); +int dns_answer_contains_nsec_or_nsec3(DnsAnswer *a); +int dns_answer_contains_zone_nsec3(DnsAnswer *answer, const char *zone); + +int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *flags); +int dns_answer_find_cname_or_dname(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *flags); + +int dns_answer_merge(DnsAnswer *a, DnsAnswer *b, DnsAnswer **ret); +int dns_answer_extend(DnsAnswer **a, DnsAnswer *b); + +void dns_answer_order_by_scope(DnsAnswer *a, bool prefer_link_local); + +int dns_answer_reserve(DnsAnswer **a, size_t n_free); +int dns_answer_reserve_or_clone(DnsAnswer **a, size_t n_free); + +int dns_answer_remove_by_key(DnsAnswer **a, const DnsResourceKey *key); +int dns_answer_remove_by_rr(DnsAnswer **a, DnsResourceRecord *rr); + +int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKey *key, DnsAnswerFlags or_flags); +int dns_answer_move_by_key(DnsAnswer **to, DnsAnswer **from, const DnsResourceKey *key, DnsAnswerFlags or_flags); + +int dns_answer_has_dname_for_cname(DnsAnswer *a, DnsResourceRecord *cname); + +static inline size_t dns_answer_size(DnsAnswer *a) { + return a ? a->n_rrs : 0; +} + +static inline bool dns_answer_isempty(DnsAnswer *a) { + return dns_answer_size(a) <= 0; +} + +void dns_answer_dump(DnsAnswer *answer, FILE *f); + +DEFINE_TRIVIAL_CLEANUP_FUNC(DnsAnswer*, dns_answer_unref); + +#define _DNS_ANSWER_FOREACH(q, kk, a) \ + for (size_t UNIQ_T(i, q) = ({ \ + (kk) = ((a) && (a)->n_rrs > 0) ? (a)->items[0].rr : NULL; \ + 0; \ + }); \ + (a) && (UNIQ_T(i, q) < (a)->n_rrs); \ + UNIQ_T(i, q)++, (kk) = (UNIQ_T(i, q) < (a)->n_rrs ? (a)->items[UNIQ_T(i, q)].rr : NULL)) + +#define DNS_ANSWER_FOREACH(kk, a) _DNS_ANSWER_FOREACH(UNIQ, kk, a) + +#define _DNS_ANSWER_FOREACH_IFINDEX(q, kk, ifi, a) \ + for (size_t UNIQ_T(i, q) = ({ \ + (kk) = ((a) && (a)->n_rrs > 0) ? (a)->items[0].rr : NULL; \ + (ifi) = ((a) && (a)->n_rrs > 0) ? (a)->items[0].ifindex : 0; \ + 0; \ + }); \ + (a) && (UNIQ_T(i, q) < (a)->n_rrs); \ + UNIQ_T(i, q)++, \ + (kk) = ((UNIQ_T(i, q) < (a)->n_rrs) ? (a)->items[UNIQ_T(i, q)].rr : NULL), \ + (ifi) = ((UNIQ_T(i, q) < (a)->n_rrs) ? (a)->items[UNIQ_T(i, q)].ifindex : 0)) + +#define DNS_ANSWER_FOREACH_IFINDEX(kk, ifindex, a) _DNS_ANSWER_FOREACH_IFINDEX(UNIQ, kk, ifindex, a) + +#define _DNS_ANSWER_FOREACH_FLAGS(q, kk, fl, a) \ + for (size_t UNIQ_T(i, q) = ({ \ + (kk) = ((a) && (a)->n_rrs > 0) ? (a)->items[0].rr : NULL; \ + (fl) = ((a) && (a)->n_rrs > 0) ? (a)->items[0].flags : 0; \ + 0; \ + }); \ + (a) && (UNIQ_T(i, q) < (a)->n_rrs); \ + UNIQ_T(i, q)++, \ + (kk) = ((UNIQ_T(i, q) < (a)->n_rrs) ? (a)->items[UNIQ_T(i, q)].rr : NULL), \ + (fl) = ((UNIQ_T(i, q) < (a)->n_rrs) ? (a)->items[UNIQ_T(i, q)].flags : 0)) + +#define DNS_ANSWER_FOREACH_FLAGS(kk, flags, a) _DNS_ANSWER_FOREACH_FLAGS(UNIQ, kk, flags, a) + +#define _DNS_ANSWER_FOREACH_FULL(q, kk, ifi, fl, a) \ + for (size_t UNIQ_T(i, q) = ({ \ + (kk) = ((a) && (a)->n_rrs > 0) ? (a)->items[0].rr : NULL; \ + (ifi) = ((a) && (a)->n_rrs > 0) ? (a)->items[0].ifindex : 0; \ + (fl) = ((a) && (a)->n_rrs > 0) ? (a)->items[0].flags : 0; \ + 0; \ + }); \ + (a) && (UNIQ_T(i, q) < (a)->n_rrs); \ + UNIQ_T(i, q)++, \ + (kk) = ((UNIQ_T(i, q) < (a)->n_rrs) ? (a)->items[UNIQ_T(i, q)].rr : NULL), \ + (ifi) = ((UNIQ_T(i, q) < (a)->n_rrs) ? (a)->items[UNIQ_T(i, q)].ifindex : 0), \ + (fl) = ((UNIQ_T(i, q) < (a)->n_rrs) ? (a)->items[UNIQ_T(i, q)].flags : 0)) + +#define DNS_ANSWER_FOREACH_FULL(kk, ifindex, flags, a) _DNS_ANSWER_FOREACH_FULL(UNIQ, kk, ifindex, flags, a) |