diff --git a/src/basic/bitmap.c b/src/basic/bitmap.c index ad1fda0198..f4b12fc261 100644 --- a/src/basic/bitmap.c +++ b/src/basic/bitmap.c @@ -50,6 +50,23 @@ Bitmap *bitmap_new(void) { return new0(Bitmap, 1); } +Bitmap *bitmap_copy(Bitmap *b) { + Bitmap *ret; + + ret = bitmap_new(); + if (!ret) + return NULL; + + ret->bitmaps = newdup(uint64_t, b->bitmaps, b->n_bitmaps); + if (!ret->bitmaps) { + free(ret); + return NULL; + } + + ret->n_bitmaps = ret->bitmaps_allocated = b->n_bitmaps; + return ret; +} + void bitmap_free(Bitmap *b) { if (!b) return; diff --git a/src/basic/bitmap.h b/src/basic/bitmap.h index f5f8f2f018..63fdbe8bea 100644 --- a/src/basic/bitmap.h +++ b/src/basic/bitmap.h @@ -27,10 +27,9 @@ typedef struct Bitmap Bitmap; Bitmap *bitmap_new(void); - -void bitmap_free(Bitmap *b); - +Bitmap *bitmap_copy(Bitmap *b); int bitmap_ensure_allocated(Bitmap **b); +void bitmap_free(Bitmap *b); int bitmap_set(Bitmap *b, unsigned n); void bitmap_unset(Bitmap *b, unsigned n); diff --git a/src/resolve/resolved-bus.c b/src/resolve/resolved-bus.c index 1f7883c067..2ca65e6953 100644 --- a/src/resolve/resolved-bus.c +++ b/src/resolve/resolved-bus.c @@ -672,6 +672,10 @@ static int bus_method_resolve_record(sd_bus_message *message, void *userdata, sd if (r < 0) return r; + /* Let's request that the TTL is fixed up for locally cached entries, after all we return it in the wire format + * blob */ + q->clamp_ttl = true; + q->request = sd_bus_message_ref(message); q->complete = bus_method_resolve_record_complete; diff --git a/src/resolve/resolved-dns-cache.c b/src/resolve/resolved-dns-cache.c index 77c42d7aad..0bb5a95188 100644 --- a/src/resolve/resolved-dns-cache.c +++ b/src/resolve/resolved-dns-cache.c @@ -790,7 +790,7 @@ static DnsCacheItem *dns_cache_get_by_key_follow_cname_dname_nsec(DnsCache *c, D return NULL; } -int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, int *rcode, DnsAnswer **ret, bool *authenticated) { +int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, bool clamp_ttl, int *rcode, DnsAnswer **ret, bool *authenticated) { _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; char key_str[DNS_RESOURCE_KEY_STRING_MAX]; unsigned n = 0; @@ -798,6 +798,7 @@ int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, int *rcode, DnsAnswer **r bool nxdomain = false; DnsCacheItem *j, *first, *nsec = NULL; bool have_authenticated = false, have_non_authenticated = false; + usec_t current; assert(c); assert(key); @@ -892,11 +893,24 @@ int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, int *rcode, DnsAnswer **r if (!answer) return -ENOMEM; + if (clamp_ttl) + current = now(clock_boottime_or_monotonic()); + LIST_FOREACH(by_key, j, first) { + _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; + if (!j->rr) continue; - r = dns_answer_add(answer, j->rr, j->ifindex, j->authenticated ? DNS_ANSWER_AUTHENTICATED : 0); + if (clamp_ttl) { + rr = dns_resource_record_ref(j->rr); + + r = dns_resource_record_clamp_ttl(&rr, LESS_BY(j->until, current) / USEC_PER_SEC); + if (r < 0) + return r; + } + + r = dns_answer_add(answer, rr ?: j->rr, j->ifindex, j->authenticated ? DNS_ANSWER_AUTHENTICATED : 0); if (r < 0) return r; } diff --git a/src/resolve/resolved-dns-cache.h b/src/resolve/resolved-dns-cache.h index 2293718e86..22a7c17377 100644 --- a/src/resolve/resolved-dns-cache.h +++ b/src/resolve/resolved-dns-cache.h @@ -40,7 +40,7 @@ void dns_cache_flush(DnsCache *c); void dns_cache_prune(DnsCache *c); int dns_cache_put(DnsCache *c, DnsResourceKey *key, int rcode, DnsAnswer *answer, bool authenticated, uint32_t nsec_ttl, usec_t timestamp, int owner_family, const union in_addr_union *owner_address); -int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, int *rcode, DnsAnswer **answer, bool *authenticated); +int dns_cache_lookup(DnsCache *c, DnsResourceKey *key, bool clamp_ttl, int *rcode, DnsAnswer **answer, bool *authenticated); int dns_cache_check_conflicts(DnsCache *cache, DnsResourceRecord *rr, int owner_family, const union in_addr_union *owner_address); diff --git a/src/resolve/resolved-dns-query.c b/src/resolve/resolved-dns-query.c index ea04e58d61..8578774c37 100644 --- a/src/resolve/resolved-dns-query.c +++ b/src/resolve/resolved-dns-query.c @@ -154,6 +154,7 @@ static int dns_query_candidate_add_transaction(DnsQueryCandidate *c, DnsResource goto gc; } + t->clamp_ttl = c->query->clamp_ttl; return 1; gc: @@ -420,7 +421,8 @@ int dns_query_new( DnsQuery **ret, DnsQuestion *question_utf8, DnsQuestion *question_idna, - int ifindex, uint64_t flags) { + int ifindex, + uint64_t flags) { _cleanup_(dns_query_freep) DnsQuery *q = NULL; DnsResourceKey *key; diff --git a/src/resolve/resolved-dns-query.h b/src/resolve/resolved-dns-query.h index c2ac02f68b..53f48d462b 100644 --- a/src/resolve/resolved-dns-query.h +++ b/src/resolve/resolved-dns-query.h @@ -71,6 +71,10 @@ struct DnsQuery { * family */ bool suppress_unroutable_family; + + /* If true, the RR TTLs of the answer will be clamped by their current left validity in the cache */ + bool clamp_ttl; + DnsTransactionState state; unsigned n_cname_redirects; diff --git a/src/resolve/resolved-dns-rr.c b/src/resolve/resolved-dns-rr.c index 6a29a93a26..5687588a7d 100644 --- a/src/resolve/resolved-dns-rr.c +++ b/src/resolve/resolved-dns-rr.c @@ -1532,6 +1532,232 @@ const struct hash_ops dns_resource_record_hash_ops = { .compare = dns_resource_record_compare_func, }; +DnsResourceRecord *dns_resource_record_copy(DnsResourceRecord *rr) { + _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *copy = NULL; + DnsResourceRecord *t; + + assert(rr); + + copy = dns_resource_record_new(rr->key); + if (!copy) + return NULL; + + copy->ttl = rr->ttl; + copy->expiry = rr->expiry; + copy->n_skip_labels_signer = rr->n_skip_labels_signer; + copy->n_skip_labels_source = rr->n_skip_labels_source; + copy->unparseable = rr->unparseable; + + switch (rr->unparseable ? _DNS_TYPE_INVALID : rr->key->type) { + + case DNS_TYPE_SRV: + copy->srv.priority = rr->srv.priority; + copy->srv.weight = rr->srv.weight; + copy->srv.port = rr->srv.port; + copy->srv.name = strdup(rr->srv.name); + if (!copy->srv.name) + return NULL; + break; + + case DNS_TYPE_PTR: + case DNS_TYPE_NS: + case DNS_TYPE_CNAME: + case DNS_TYPE_DNAME: + copy->ptr.name = strdup(rr->ptr.name); + if (!copy->ptr.name) + return NULL; + break; + + case DNS_TYPE_HINFO: + copy->hinfo.cpu = strdup(rr->hinfo.cpu); + if (!copy->hinfo.cpu) + return NULL; + + copy->hinfo.os = strdup(rr->hinfo.os); + if(!copy->hinfo.os) + return NULL; + break; + + case DNS_TYPE_TXT: + case DNS_TYPE_SPF: + copy->txt.items = dns_txt_item_copy(rr->txt.items); + if (!copy->txt.items) + return NULL; + break; + + case DNS_TYPE_A: + copy->a = rr->a; + break; + + case DNS_TYPE_AAAA: + copy->aaaa = rr->aaaa; + break; + + case DNS_TYPE_SOA: + copy->soa.mname = strdup(rr->soa.mname); + if (!copy->soa.mname) + return NULL; + copy->soa.rname = strdup(rr->soa.rname); + if (!copy->soa.rname) + return NULL; + copy->soa.serial = rr->soa.serial; + copy->soa.refresh = rr->soa.refresh; + copy->soa.retry = rr->soa.retry; + copy->soa.expire = rr->soa.expire; + copy->soa.minimum = rr->soa.minimum; + break; + + case DNS_TYPE_MX: + copy->mx.priority = rr->mx.priority; + copy->mx.exchange = strdup(rr->mx.exchange); + if (!copy->mx.exchange) + return NULL; + break; + + case DNS_TYPE_LOC: + copy->loc = rr->loc; + break; + + case DNS_TYPE_SSHFP: + copy->sshfp.algorithm = rr->sshfp.algorithm; + copy->sshfp.fptype = rr->sshfp.fptype; + copy->sshfp.fingerprint = memdup(rr->sshfp.fingerprint, rr->sshfp.fingerprint_size); + if (!copy->sshfp.fingerprint) + return NULL; + copy->sshfp.fingerprint_size = rr->sshfp.fingerprint_size; + break; + + case DNS_TYPE_DNSKEY: + copy->dnskey.flags = rr->dnskey.flags; + copy->dnskey.protocol = rr->dnskey.protocol; + copy->dnskey.algorithm = rr->dnskey.algorithm; + copy->dnskey.key = memdup(rr->dnskey.key, rr->dnskey.key_size); + if (!copy->dnskey.key) + return NULL; + copy->dnskey.key_size = rr->dnskey.key_size; + break; + + case DNS_TYPE_RRSIG: + copy->rrsig.type_covered = rr->rrsig.type_covered; + copy->rrsig.algorithm = rr->rrsig.algorithm; + copy->rrsig.labels = rr->rrsig.labels; + copy->rrsig.original_ttl = rr->rrsig.original_ttl; + copy->rrsig.expiration = rr->rrsig.expiration; + copy->rrsig.inception = rr->rrsig.inception; + copy->rrsig.key_tag = rr->rrsig.key_tag; + copy->rrsig.signer = strdup(rr->rrsig.signer); + if (!copy->rrsig.signer) + return NULL; + copy->rrsig.signature = memdup(rr->rrsig.signature, rr->rrsig.signature_size); + if (!copy->rrsig.signature) + return NULL; + copy->rrsig.signature_size = rr->rrsig.signature_size; + break; + + case DNS_TYPE_NSEC: + copy->nsec.next_domain_name = strdup(rr->nsec.next_domain_name); + if (!copy->nsec.next_domain_name) + return NULL; + copy->nsec.types = bitmap_copy(rr->nsec.types); + if (!copy->nsec.types) + return NULL; + break; + + case DNS_TYPE_DS: + copy->ds.key_tag = rr->ds.key_tag; + copy->ds.algorithm = rr->ds.algorithm; + copy->ds.digest_type = rr->ds.digest_type; + copy->ds.digest = memdup(rr->ds.digest, rr->ds.digest_size); + if (!copy->ds.digest) + return NULL; + copy->ds.digest_size = rr->ds.digest_size; + break; + + case DNS_TYPE_NSEC3: + copy->nsec3.algorithm = rr->nsec3.algorithm; + copy->nsec3.flags = rr->nsec3.flags; + copy->nsec3.iterations = rr->nsec3.iterations; + copy->nsec3.salt = memdup(rr->nsec3.salt, rr->nsec3.salt_size); + if (!copy->nsec3.salt) + return NULL; + copy->nsec3.salt_size = rr->nsec3.salt_size; + copy->nsec3.next_hashed_name = memdup(rr->nsec3.next_hashed_name, rr->nsec3.next_hashed_name_size); + if (!copy->nsec3.next_hashed_name_size) + return NULL; + copy->nsec3.next_hashed_name_size = rr->nsec3.next_hashed_name_size; + copy->nsec3.types = bitmap_copy(rr->nsec3.types); + if (!copy->nsec3.types) + return NULL; + break; + + case DNS_TYPE_TLSA: + copy->tlsa.cert_usage = rr->tlsa.cert_usage; + copy->tlsa.selector = rr->tlsa.selector; + copy->tlsa.matching_type = rr->tlsa.matching_type; + copy->tlsa.data = memdup(rr->tlsa.data, rr->tlsa.data_size); + if (!copy->tlsa.data) + return NULL; + copy->tlsa.data_size = rr->tlsa.data_size; + break; + + case DNS_TYPE_CAA: + copy->caa.flags = rr->caa.flags; + copy->caa.tag = strdup(rr->caa.tag); + if (!copy->caa.tag) + return NULL; + copy->caa.value = memdup(rr->caa.value, rr->caa.value_size); + if (!copy->caa.value) + return NULL; + copy->caa.value_size = rr->caa.value_size; + break; + + case DNS_TYPE_OPT: + default: + copy->generic.data = memdup(rr->generic.data, rr->generic.data_size); + if (!copy->generic.data) + return NULL; + copy->generic.data_size = rr->generic.data_size; + break; + } + + t = copy; + copy = NULL; + + return t; +} + +int dns_resource_record_clamp_ttl(DnsResourceRecord **rr, uint32_t max_ttl) { + DnsResourceRecord *old_rr, *new_rr; + uint32_t new_ttl; + + assert(rr); + old_rr = *rr; + + if (old_rr->key->type == DNS_TYPE_OPT) + return -EINVAL; + + new_ttl = MIN(old_rr->ttl, max_ttl); + if (new_ttl == old_rr->ttl) + return 0; + + if (old_rr->n_ref == 1) { + /* Patch in place */ + old_rr->ttl = new_ttl; + return 1; + } + + new_rr = dns_resource_record_copy(old_rr); + if (!new_rr) + return -ENOMEM; + + new_rr->ttl = new_ttl; + + dns_resource_record_unref(*rr); + *rr = new_rr; + + return 1; +} + DnsTxtItem *dns_txt_item_free_all(DnsTxtItem *i) { DnsTxtItem *n; @@ -1564,6 +1790,25 @@ bool dns_txt_item_equal(DnsTxtItem *a, DnsTxtItem *b) { return dns_txt_item_equal(a->items_next, b->items_next); } +DnsTxtItem *dns_txt_item_copy(DnsTxtItem *first) { + DnsTxtItem *i, *copy = NULL, *end = NULL; + + LIST_FOREACH(items, i, first) { + DnsTxtItem *j; + + j = memdup(i, offsetof(DnsTxtItem, data) + i->length + 1); + if (!j) { + dns_txt_item_free_all(copy); + return NULL; + } + + LIST_INSERT_AFTER(items, copy, end, j); + end = j; + } + + return copy; +} + static const char* const dnssec_algorithm_table[_DNSSEC_ALGORITHM_MAX_DEFINED] = { /* Mnemonics as listed on https://www.iana.org/assignments/dns-sec-alg-numbers/dns-sec-alg-numbers.xhtml */ [DNSSEC_ALGORITHM_RSAMD5] = "RSAMD5", diff --git a/src/resolve/resolved-dns-rr.h b/src/resolve/resolved-dns-rr.h index 020a2abd77..8b2d4df9e7 100644 --- a/src/resolve/resolved-dns-rr.h +++ b/src/resolve/resolved-dns-rr.h @@ -318,6 +318,7 @@ int dns_resource_record_new_reverse(DnsResourceRecord **ret, int family, const u int dns_resource_record_new_address(DnsResourceRecord **ret, int family, const union in_addr_union *address, const char *name); int dns_resource_record_equal(const DnsResourceRecord *a, const DnsResourceRecord *b); const char* dns_resource_record_to_string(DnsResourceRecord *rr); +DnsResourceRecord *dns_resource_record_copy(DnsResourceRecord *rr); DEFINE_TRIVIAL_CLEANUP_FUNC(DnsResourceRecord*, dns_resource_record_unref); int dns_resource_record_to_wire_format(DnsResourceRecord *rr, bool canonical); @@ -327,8 +328,11 @@ int dns_resource_record_source(DnsResourceRecord *rr, const char **ret); int dns_resource_record_is_signer(DnsResourceRecord *rr, const char *zone); int dns_resource_record_is_synthetic(DnsResourceRecord *rr); +int dns_resource_record_clamp_ttl(DnsResourceRecord **rr, uint32_t max_ttl); + DnsTxtItem *dns_txt_item_free_all(DnsTxtItem *i); bool dns_txt_item_equal(DnsTxtItem *a, DnsTxtItem *b); +DnsTxtItem *dns_txt_item_copy(DnsTxtItem *i); void dns_resource_record_hash_func(const void *i, struct siphash *state); diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c index bcb1b6d8a7..2d1767be0a 100644 --- a/src/resolve/resolved-dns-transaction.c +++ b/src/resolve/resolved-dns-transaction.c @@ -1274,7 +1274,7 @@ static int dns_transaction_prepare(DnsTransaction *t, usec_t ts) { /* Let's then prune all outdated entries */ dns_cache_prune(&t->scope->cache); - r = dns_cache_lookup(&t->scope->cache, t->key, &t->answer_rcode, &t->answer, &t->answer_authenticated); + r = dns_cache_lookup(&t->scope->cache, t->key, t->clamp_ttl, &t->answer_rcode, &t->answer, &t->answer_authenticated); if (r < 0) return r; if (r > 0) { diff --git a/src/resolve/resolved-dns-transaction.h b/src/resolve/resolved-dns-transaction.h index eaece91533..46a934a39b 100644 --- a/src/resolve/resolved-dns-transaction.h +++ b/src/resolve/resolved-dns-transaction.h @@ -74,6 +74,8 @@ struct DnsTransaction { bool initial_jitter_scheduled:1; bool initial_jitter_elapsed:1; + bool clamp_ttl:1; + DnsPacket *sent, *received; DnsAnswer *answer; diff --git a/src/resolve/test-dns-packet.c b/src/resolve/test-dns-packet.c index 41e5c1caa5..956b155872 100644 --- a/src/resolve/test-dns-packet.c +++ b/src/resolve/test-dns-packet.c @@ -33,6 +33,19 @@ #define HASH_KEY SD_ID128_MAKE(d3,1e,48,90,4b,fa,4c,fe,af,9d,d5,a1,d7,2e,8a,b1) +static void verify_rr_copy(DnsResourceRecord *rr) { + _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *copy = NULL; + const char *a, *b; + + assert_se(copy = dns_resource_record_copy(rr)); + assert_se(dns_resource_record_equal(copy, rr) > 0); + + assert_se(a = dns_resource_record_to_string(rr)); + assert_se(b = dns_resource_record_to_string(copy)); + + assert_se(streq(a, b)); +} + static uint64_t hash(DnsResourceRecord *rr) { struct siphash state; @@ -66,6 +79,8 @@ static void test_packet_from_file(const char* filename, bool canonical) { assert_se(dns_packet_append_blob(p, data + offset + 8, packet_size, NULL) >= 0); assert_se(dns_packet_read_rr(p, &rr, NULL, NULL) >= 0); + verify_rr_copy(rr); + s = dns_resource_record_to_string(rr); assert_se(s); puts(s); @@ -78,6 +93,8 @@ static void test_packet_from_file(const char* filename, bool canonical) { assert_se(dns_packet_append_blob(p2, rr->wire_format, rr->wire_format_size, NULL) >= 0); assert_se(dns_packet_read_rr(p2, &rr2, NULL, NULL) >= 0); + verify_rr_copy(rr); + s2 = dns_resource_record_to_string(rr); assert_se(s2); assert_se(streq(s, s2));