[thirdparty/systemd.git] / src / resolve / resolved-dns-answer.h

/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once

#include "ordered-set.h"
#include "resolved-forward.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 */
        DNS_ANSWER_SECTION_ANSWER      = 1 << 5, /* When parsing: RR originates from answer section */
        DNS_ANSWER_SECTION_AUTHORITY   = 1 << 6, /* When parsing: RR originates from authority section */
        DNS_ANSWER_SECTION_ADDITIONAL  = 1 << 7, /* When parsing: RR originates from additional section */
        DNS_ANSWER_REFUSE_TTL_NO_MATCH = 1 << 8, /* For mDNS; refuse to merge a zero TTL RR with a nonzero TTL RR */

        DNS_ANSWER_MASK_SECTIONS      = DNS_ANSWER_SECTION_ANSWER|
                                        DNS_ANSWER_SECTION_AUTHORITY|
                                        DNS_ANSWER_SECTION_ADDITIONAL,
} DnsAnswerFlags;

typedef struct DnsAnswerItem {
        unsigned n_ref;
        DnsResourceRecord *rr;
        DnsResourceRecord *rrsig; /* Optionally, also store RRSIG RR that successfully validates this item */
        int ifindex;
        DnsAnswerFlags flags;
} DnsAnswerItem;

typedef struct DnsAnswer {
        unsigned n_ref;
        OrderedSet *items;
} DnsAnswer;

DnsAnswer *dns_answer_new(size_t n);
DnsAnswer *dns_answer_ref(DnsAnswer *a);
DnsAnswer *dns_answer_unref(DnsAnswer *a);

#define DNS_ANSWER_REPLACE(a, b)                \
        do {                                    \
                typeof(a)* _a = &(a);           \
                typeof(b) _b = (b);             \
                dns_answer_unref(*_a);          \
                *_a = _b;                       \
        } while(0)

int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags, DnsResourceRecord *rrsig);
int dns_answer_add_extend(DnsAnswer **a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags, DnsResourceRecord *rrsig);
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 *ret_flags);
bool dns_answer_contains_nsec_or_nsec3(DnsAnswer *a);
int dns_answer_contains_zone_nsec3(DnsAnswer *answer, const char *zone);
bool dns_answer_contains(DnsAnswer *answer, DnsResourceRecord *rr);

int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *ret_flags);
int dns_answer_find_cname_or_dname(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *ret_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_remove_by_answer_keys(DnsAnswer **a, DnsAnswer *b);

int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKey *key, DnsAnswerFlags or_flags, DnsResourceRecord *rrsig);
int dns_answer_move_by_key(DnsAnswer **to, DnsAnswer **from, const DnsResourceKey *key, DnsAnswerFlags or_flags, DnsResourceRecord *rrsig);

int dns_answer_has_dname_for_cname(DnsAnswer *a, DnsResourceRecord *cname);

static inline size_t dns_answer_size(DnsAnswer *a) {
        return a ? ordered_set_size(a->items) : 0;
}

static inline bool dns_answer_isempty(DnsAnswer *a) {
        return dns_answer_size(a) <= 0;
}

void dns_answer_dump(DnsAnswer *answer, FILE *f);

void dns_answer_randomize(DnsAnswer *a);

uint32_t dns_answer_min_ttl(DnsAnswer *a);

DEFINE_TRIVIAL_CLEANUP_FUNC(DnsAnswer*, dns_answer_unref);

typedef struct DnsAnswerIterator {
        Iterator iterator;
        DnsAnswer *answer;
        DnsAnswerItem *item;
} DnsAnswerIterator;

#define _DNS_ANSWER_FOREACH(kk, a, i)                                   \
        for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) };  \
             i.answer &&                                                \
             ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
             (kk = i.item->rr, true); )

#define DNS_ANSWER_FOREACH(rr, a) _DNS_ANSWER_FOREACH(rr, a, UNIQ_T(i, UNIQ))

#define _DNS_ANSWER_FOREACH_IFINDEX(kk, ifi, a, i)                      \
        for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) };  \
             i.answer &&                                                \
             ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
             (kk = i.item->rr, ifi = i.item->ifindex, true); )

#define DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, a) _DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, a, UNIQ_T(i, UNIQ))

#define _DNS_ANSWER_FOREACH_FLAGS(kk, fl, a, i)                         \
        for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) };  \
             i.answer &&                                                \
             ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
             (kk = i.item->rr, fl = i.item->flags, true); )

#define DNS_ANSWER_FOREACH_FLAGS(rr, flags, a) _DNS_ANSWER_FOREACH_FLAGS(rr, flags, a, UNIQ_T(i, UNIQ))

#define _DNS_ANSWER_FOREACH_ITEM(it, a, i)                            \
        for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) };  \
             i.answer &&                                                \
             ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
             (it = i.item, true); )

#define DNS_ANSWER_FOREACH_ITEM(item, a) _DNS_ANSWER_FOREACH_ITEM(item, a, UNIQ_T(i, UNIQ))
Commit	Line	Data
	1	/* SPDX-License-Identifier: LGPL-2.1-or-later */
	2	#pragma once
	3
	4	#include "ordered-set.h"
	5	#include "resolved-forward.h"
	6
	7	/* A simple array of resource records. We keep track of the originating ifindex for each RR where that makes
	8	* sense, so that we can qualify A and AAAA RRs referring to a local link with the right ifindex.
	9	*
	10	* Note that we usually encode the empty DnsAnswer object as a simple NULL. */
	11
	12	typedef enum DnsAnswerFlags {
	13	DNS_ANSWER_AUTHENTICATED = 1 << 0, /* Item has been authenticated */
	14	DNS_ANSWER_CACHEABLE = 1 << 1, /* Item is subject to caching */
	15	DNS_ANSWER_SHARED_OWNER = 1 << 2, /* For mDNS: RRset may be owner by multiple peers */
	16	DNS_ANSWER_CACHE_FLUSH = 1 << 3, /* For mDNS: sets cache-flush bit in the rrclass of response records */
	17	DNS_ANSWER_GOODBYE = 1 << 4, /* For mDNS: item is subject to disappear */
	18	DNS_ANSWER_SECTION_ANSWER = 1 << 5, /* When parsing: RR originates from answer section */
	19	DNS_ANSWER_SECTION_AUTHORITY = 1 << 6, /* When parsing: RR originates from authority section */
	20	DNS_ANSWER_SECTION_ADDITIONAL = 1 << 7, /* When parsing: RR originates from additional section */
	21	DNS_ANSWER_REFUSE_TTL_NO_MATCH = 1 << 8, /* For mDNS; refuse to merge a zero TTL RR with a nonzero TTL RR */
	22
	23	DNS_ANSWER_MASK_SECTIONS = DNS_ANSWER_SECTION_ANSWER\|
	24	DNS_ANSWER_SECTION_AUTHORITY\|
	25	DNS_ANSWER_SECTION_ADDITIONAL,
	26	} DnsAnswerFlags;
	27
	28	typedef struct DnsAnswerItem {
	29	unsigned n_ref;
	30	DnsResourceRecord *rr;
	31	DnsResourceRecord rrsig; / Optionally, also store RRSIG RR that successfully validates this item */
	32	int ifindex;
	33	DnsAnswerFlags flags;
	34	} DnsAnswerItem;
	35
	36	typedef struct DnsAnswer {
	37	unsigned n_ref;
	38	OrderedSet *items;
	39	} DnsAnswer;
	40
	41	DnsAnswer *dns_answer_new(size_t n);
	42	DnsAnswer dns_answer_ref(DnsAnswer a);
	43	DnsAnswer dns_answer_unref(DnsAnswer a);
	44
	45	#define DNS_ANSWER_REPLACE(a, b) \
	46	do { \
	47	typeof(a)* _a = &(a); \
	48	typeof(b) _b = (b); \
	49	dns_answer_unref(*_a); \
	50	*_a = _b; \
	51	} while(0)
	52
	53	int dns_answer_add(DnsAnswer a, DnsResourceRecord rr, int ifindex, DnsAnswerFlags flags, DnsResourceRecord *rrsig);
	54	int dns_answer_add_extend(DnsAnswer *a, DnsResourceRecord rr, int ifindex, DnsAnswerFlags flags, DnsResourceRecord *rrsig);
	55	int dns_answer_add_soa(DnsAnswer a, const char name, uint32_t ttl, int ifindex);
	56
	57	int dns_answer_match_key(DnsAnswer a, const DnsResourceKey key, DnsAnswerFlags *ret_flags);
	58	bool dns_answer_contains_nsec_or_nsec3(DnsAnswer *a);
	59	int dns_answer_contains_zone_nsec3(DnsAnswer answer, const char zone);
	60	bool dns_answer_contains(DnsAnswer answer, DnsResourceRecord rr);
	61
	62	int dns_answer_find_soa(DnsAnswer a, const DnsResourceKey key, DnsResourceRecord *ret, DnsAnswerFlags ret_flags);
	63	int dns_answer_find_cname_or_dname(DnsAnswer a, const DnsResourceKey key, DnsResourceRecord *ret, DnsAnswerFlags ret_flags);
	64
	65	int dns_answer_merge(DnsAnswer a, DnsAnswer b, DnsAnswer **ret);
	66	int dns_answer_extend(DnsAnswer *a, DnsAnswer b);
	67
	68	void dns_answer_order_by_scope(DnsAnswer *a, bool prefer_link_local);
	69
	70	int dns_answer_reserve(DnsAnswer **a, size_t n_free);
	71	int dns_answer_reserve_or_clone(DnsAnswer **a, size_t n_free);
	72
	73	int dns_answer_remove_by_key(DnsAnswer *a, const DnsResourceKey key);
	74	int dns_answer_remove_by_rr(DnsAnswer *a, DnsResourceRecord rr);
	75	int dns_answer_remove_by_answer_keys(DnsAnswer *a, DnsAnswer b);
	76
	77	int dns_answer_copy_by_key(DnsAnswer *a, DnsAnswer source, const DnsResourceKey key, DnsAnswerFlags or_flags, DnsResourceRecord rrsig);
	78	int dns_answer_move_by_key(DnsAnswer to, DnsAnswer from, const DnsResourceKey key, DnsAnswerFlags or_flags, DnsResourceRecord rrsig);
	79
	80	int dns_answer_has_dname_for_cname(DnsAnswer a, DnsResourceRecord cname);
	81
	82	static inline size_t dns_answer_size(DnsAnswer *a) {
	83	return a ? ordered_set_size(a->items) : 0;
	84	}
	85
	86	static inline bool dns_answer_isempty(DnsAnswer *a) {
	87	return dns_answer_size(a) <= 0;
	88	}
	89
	90	void dns_answer_dump(DnsAnswer answer, FILE f);
	91
	92	void dns_answer_randomize(DnsAnswer *a);
	93
	94	uint32_t dns_answer_min_ttl(DnsAnswer *a);
	95
	96	DEFINE_TRIVIAL_CLEANUP_FUNC(DnsAnswer*, dns_answer_unref);
	97
	98	typedef struct DnsAnswerIterator {
	99	Iterator iterator;
	100	DnsAnswer *answer;
	101	DnsAnswerItem *item;
	102	} DnsAnswerIterator;
	103
	104	#define _DNS_ANSWER_FOREACH(kk, a, i) \
	105	for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) }; \
	106	i.answer && \
	107	ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
	108	(kk = i.item->rr, true); )
	109
	110	#define DNS_ANSWER_FOREACH(rr, a) _DNS_ANSWER_FOREACH(rr, a, UNIQ_T(i, UNIQ))
	111
	112	#define _DNS_ANSWER_FOREACH_IFINDEX(kk, ifi, a, i) \
	113	for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) }; \
	114	i.answer && \
	115	ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
	116	(kk = i.item->rr, ifi = i.item->ifindex, true); )
	117
	118	#define DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, a) _DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, a, UNIQ_T(i, UNIQ))
	119
	120	#define _DNS_ANSWER_FOREACH_FLAGS(kk, fl, a, i) \
	121	for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) }; \
	122	i.answer && \
	123	ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
	124	(kk = i.item->rr, fl = i.item->flags, true); )
	125
	126	#define DNS_ANSWER_FOREACH_FLAGS(rr, flags, a) _DNS_ANSWER_FOREACH_FLAGS(rr, flags, a, UNIQ_T(i, UNIQ))
	127
	128	#define _DNS_ANSWER_FOREACH_ITEM(it, a, i) \
	129	for (DnsAnswerIterator i = { .iterator = ITERATOR_FIRST, .answer = (a) }; \
	130	i.answer && \
	131	ordered_set_iterate(i.answer->items, &i.iterator, (void**) &(i.item)) && \
	132	(it = i.item, true); )
	133
	134	#define DNS_ANSWER_FOREACH_ITEM(item, a) _DNS_ANSWER_FOREACH_ITEM(item, a, UNIQ_T(i, UNIQ))