diff options
Diffstat (limited to 'src/resolve/resolved-dns-answer.c')
-rw-r--r-- | src/resolve/resolved-dns-answer.c | 353 |
1 files changed, 304 insertions, 49 deletions
diff --git a/src/resolve/resolved-dns-answer.c b/src/resolve/resolved-dns-answer.c index 55e6ffbad7..b50558e280 100644 --- a/src/resolve/resolved-dns-answer.c +++ b/src/resolve/resolved-dns-answer.c @@ -22,6 +22,7 @@ #include "alloc-util.h" #include "dns-domain.h" #include "resolved-dns-answer.h" +#include "resolved-dns-dnssec.h" #include "string-util.h" DnsAnswer *dns_answer_new(unsigned n) { @@ -73,7 +74,7 @@ DnsAnswer *dns_answer_unref(DnsAnswer *a) { return NULL; } -static int dns_answer_add_raw(DnsAnswer *a, DnsResourceRecord *rr, int ifindex) { +static int dns_answer_add_raw(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) { assert(rr); if (!a) @@ -82,19 +83,22 @@ static int dns_answer_add_raw(DnsAnswer *a, DnsResourceRecord *rr, int ifindex) if (a->n_rrs >= a->n_allocated) return -ENOSPC; - a->items[a->n_rrs].rr = dns_resource_record_ref(rr); - a->items[a->n_rrs].ifindex = ifindex; - a->n_rrs++; + a->items[a->n_rrs++] = (DnsAnswerItem) { + .rr = dns_resource_record_ref(rr), + .ifindex = ifindex, + .flags = flags, + }; return 1; } static int dns_answer_add_raw_all(DnsAnswer *a, DnsAnswer *source) { DnsResourceRecord *rr; + DnsAnswerFlags flags; int ifindex, r; - DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, source) { - r = dns_answer_add_raw(a, rr, ifindex); + DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, source) { + r = dns_answer_add_raw(a, rr, ifindex, flags); if (r < 0) return r; } @@ -102,7 +106,7 @@ static int dns_answer_add_raw_all(DnsAnswer *a, DnsAnswer *source) { return 0; } -int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr, int ifindex) { +int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) { unsigned i; int r; @@ -121,28 +125,48 @@ int dns_answer_add(DnsAnswer *a, DnsResourceRecord *rr, int ifindex) { if (r < 0) return r; if (r > 0) { - /* Entry already exists, keep the entry with - * the higher RR, or the one with TTL 0 */ + /* Don't mix contradicting TTLs (see below) */ + if ((rr->ttl == 0) != (a->items[i].rr->ttl == 0)) + return -EINVAL; - if (rr->ttl == 0 || (rr->ttl > a->items[i].rr->ttl && a->items[i].rr->ttl != 0)) { + /* Entry already exists, keep the entry with + * the higher RR. */ + if (rr->ttl > a->items[i].rr->ttl) { dns_resource_record_ref(rr); dns_resource_record_unref(a->items[i].rr); a->items[i].rr = rr; } + a->items[i].flags |= flags; return 0; } + + r = dns_resource_key_equal(a->items[i].rr->key, rr->key); + if (r < 0) + return r; + if (r > 0) { + /* There's already an RR of the same RRset in + * place! Let's see if the TTLs more or less + * match. We don't really care if they match + * precisely, but we do care whether one is 0 + * and the other is not. See RFC 2181, Section + * 5.2.*/ + + if ((rr->ttl == 0) != (a->items[i].rr->ttl == 0)) + return -EINVAL; + } } - return dns_answer_add_raw(a, rr, ifindex); + return dns_answer_add_raw(a, rr, ifindex, flags); } static int dns_answer_add_all(DnsAnswer *a, DnsAnswer *b) { DnsResourceRecord *rr; + DnsAnswerFlags flags; int ifindex, r; - DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, b) { - r = dns_answer_add(a, rr, ifindex); + DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, b) { + r = dns_answer_add(a, rr, ifindex, flags); if (r < 0) return r; } @@ -150,7 +174,7 @@ static int dns_answer_add_all(DnsAnswer *a, DnsAnswer *b) { return 0; } -int dns_answer_add_extend(DnsAnswer **a, DnsResourceRecord *rr, int ifindex) { +int dns_answer_add_extend(DnsAnswer **a, DnsResourceRecord *rr, int ifindex, DnsAnswerFlags flags) { int r; assert(a); @@ -160,7 +184,7 @@ int dns_answer_add_extend(DnsAnswer **a, DnsResourceRecord *rr, int ifindex) { if (r < 0) return r; - return dns_answer_add(*a, rr, ifindex); + return dns_answer_add(*a, rr, ifindex, flags); } int dns_answer_add_soa(DnsAnswer *a, const char *name, uint32_t ttl) { @@ -186,85 +210,177 @@ int dns_answer_add_soa(DnsAnswer *a, const char *name, uint32_t ttl) { soa->soa.expire = 1; soa->soa.minimum = ttl; - return dns_answer_add(a, soa, 0); + return dns_answer_add(a, soa, 0, DNS_ANSWER_AUTHENTICATED); } -int dns_answer_match_key(DnsAnswer *a, const DnsResourceKey *key) { +int dns_answer_match_key(DnsAnswer *a, const DnsResourceKey *key, DnsAnswerFlags *ret_flags) { + DnsAnswerFlags flags = 0, i_flags; DnsResourceRecord *i; + bool found = false; int r; assert(key); - if (!a) - return 0; - - DNS_ANSWER_FOREACH(i, a) { + DNS_ANSWER_FOREACH_FLAGS(i, i_flags, a) { r = dns_resource_key_match_rr(key, i, NULL); if (r < 0) return r; - if (r > 0) + if (r == 0) + continue; + + if (!ret_flags) return 1; + + if (found) + flags &= i_flags; + else { + flags = i_flags; + found = true; + } } - return 0; + if (ret_flags) + *ret_flags = flags; + + return found; } -int dns_answer_contains_rr(DnsAnswer *a, DnsResourceRecord *rr) { +int dns_answer_contains_rr(DnsAnswer *a, DnsResourceRecord *rr, DnsAnswerFlags *ret_flags) { + DnsAnswerFlags flags = 0, i_flags; DnsResourceRecord *i; + bool found = false; int r; assert(rr); - DNS_ANSWER_FOREACH(i, a) { + DNS_ANSWER_FOREACH_FLAGS(i, i_flags, a) { r = dns_resource_record_equal(i, rr); if (r < 0) return r; - if (r > 0) + if (r == 0) + continue; + + if (!ret_flags) return 1; + + if (found) + flags &= i_flags; + else { + flags = i_flags; + found = true; + } } - return 0; + if (ret_flags) + *ret_flags = flags; + + return found; } -int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret) { - DnsResourceRecord *rr; +int dns_answer_contains_key(DnsAnswer *a, const DnsResourceKey *key, DnsAnswerFlags *ret_flags) { + DnsAnswerFlags flags = 0, i_flags; + DnsResourceRecord *i; + bool found = false; + int r; assert(key); - assert(ret); - if (!a) - return 0; + DNS_ANSWER_FOREACH_FLAGS(i, i_flags, a) { + r = dns_resource_key_equal(i->key, key); + if (r < 0) + return r; + if (r == 0) + continue; + + if (!ret_flags) + return true; + + if (found) + flags &= i_flags; + else { + flags = i_flags; + found = true; + } + } + + if (ret_flags) + *ret_flags = flags; + + return found; +} + +int dns_answer_contains_nsec_or_nsec3(DnsAnswer *a) { + DnsResourceRecord *i; + + DNS_ANSWER_FOREACH(i, a) { + if (IN_SET(i->key->type, DNS_TYPE_NSEC, DNS_TYPE_NSEC3)) + return true; + } + + return false; +} + +int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *flags) { + DnsResourceRecord *rr, *soa = NULL; + DnsAnswerFlags rr_flags, soa_flags = 0; + int r; + + assert(key); /* For a SOA record we can never find a matching SOA record */ if (key->type == DNS_TYPE_SOA) return 0; - DNS_ANSWER_FOREACH(rr, a) { - if (dns_resource_key_match_soa(key, rr->key)) { - *ret = rr; - return 1; + DNS_ANSWER_FOREACH_FLAGS(rr, rr_flags, a) { + r = dns_resource_key_match_soa(key, rr->key); + if (r < 0) + return r; + if (r > 0) { + + if (soa) { + r = dns_name_endswith(DNS_RESOURCE_KEY_NAME(rr->key), DNS_RESOURCE_KEY_NAME(soa->key)); + if (r < 0) + return r; + if (r > 0) + continue; + } + + soa = rr; + soa_flags = rr_flags; } } - return 0; + if (!soa) + return 0; + + if (ret) + *ret = soa; + if (flags) + *flags = soa_flags; + + return 1; } -int dns_answer_find_cname_or_dname(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret) { +int dns_answer_find_cname_or_dname(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret, DnsAnswerFlags *flags) { DnsResourceRecord *rr; + DnsAnswerFlags rr_flags; + int r; assert(key); - if (!a) - return 0; - /* For a {C,D}NAME record we can never find a matching {C,D}NAME record */ - if (key->type == DNS_TYPE_CNAME || key->type == DNS_TYPE_DNAME) + if (!dns_type_may_redirect(key->type)) return 0; - DNS_ANSWER_FOREACH(rr, a) { - if (dns_resource_key_match_cname_or_dname(key, rr->key, NULL)) { + DNS_ANSWER_FOREACH_FLAGS(rr, rr_flags, a) { + r = dns_resource_key_match_cname_or_dname(key, rr->key, NULL); + if (r < 0) + return r; + if (r > 0) { if (ret) *ret = rr; + if (flags) + *flags = rr_flags; return 1; } } @@ -356,20 +472,21 @@ int dns_answer_remove_by_key(DnsAnswer **a, const DnsResourceKey *key) { if ((*a)->n_ref > 1) { _cleanup_(dns_answer_unrefp) DnsAnswer *copy = NULL; + DnsAnswerFlags flags; int ifindex; copy = dns_answer_new((*a)->n_rrs); if (!copy) return -ENOMEM; - DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, *a) { + DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, *a) { r = dns_resource_key_equal(rr->key, key); if (r < 0) return r; if (r > 0) continue; - r = dns_answer_add_raw(copy, rr, ifindex); + r = dns_answer_add_raw(copy, rr, ifindex, flags); if (r < 0) return r; } @@ -407,16 +524,103 @@ int dns_answer_remove_by_key(DnsAnswer **a, const DnsResourceKey *key) { return 1; } -int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKey *key) { +int dns_answer_remove_by_rr(DnsAnswer **a, DnsResourceRecord *rm) { + bool found = false, other = false; + DnsResourceRecord *rr; + unsigned i; + int r; + + assert(a); + assert(rm); + + /* Remove all entries matching the specified RR from *a */ + + DNS_ANSWER_FOREACH(rr, *a) { + r = dns_resource_record_equal(rr, rm); + if (r < 0) + return r; + if (r > 0) + found = true; + else + other = true; + + if (found && other) + break; + } + + if (!found) + return 0; + + if (!other) { + *a = dns_answer_unref(*a); /* Return NULL for the empty answer */ + return 1; + } + + if ((*a)->n_ref > 1) { + _cleanup_(dns_answer_unrefp) DnsAnswer *copy = NULL; + DnsAnswerFlags flags; + int ifindex; + + copy = dns_answer_new((*a)->n_rrs); + if (!copy) + return -ENOMEM; + + DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, *a) { + r = dns_resource_record_equal(rr, rm); + if (r < 0) + return r; + if (r > 0) + continue; + + r = dns_answer_add_raw(copy, rr, ifindex, flags); + if (r < 0) + return r; + } + + dns_answer_unref(*a); + *a = copy; + copy = NULL; + + return 1; + } + + /* Only a single reference, edit in-place */ + + i = 0; + for (;;) { + if (i >= (*a)->n_rrs) + break; + + r = dns_resource_record_equal((*a)->items[i].rr, rm); + if (r < 0) + return r; + if (r > 0) { + /* Kill this entry */ + + dns_resource_record_unref((*a)->items[i].rr); + memmove((*a)->items + i, (*a)->items + i + 1, sizeof(DnsAnswerItem) * ((*a)->n_rrs - i - 1)); + (*a)->n_rrs --; + continue; + + } else + /* Keep this entry */ + i++; + } + + return 1; +} + +int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKey *key, DnsAnswerFlags or_flags) { DnsResourceRecord *rr_source; int ifindex_source, r; + DnsAnswerFlags flags_source; assert(a); assert(key); /* Copy all RRs matching the specified key from source into *a */ - DNS_ANSWER_FOREACH_IFINDEX(rr_source, ifindex_source, source) { + DNS_ANSWER_FOREACH_FULL(rr_source, ifindex_source, flags_source, source) { r = dns_resource_key_equal(rr_source->key, key); if (r < 0) @@ -429,7 +633,7 @@ int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKe if (r < 0) return r; - r = dns_answer_add(*a, rr_source, ifindex_source); + r = dns_answer_add(*a, rr_source, ifindex_source, flags_source|or_flags); if (r < 0) return r; } @@ -437,6 +641,20 @@ int dns_answer_copy_by_key(DnsAnswer **a, DnsAnswer *source, const DnsResourceKe return 0; } +int dns_answer_move_by_key(DnsAnswer **to, DnsAnswer **from, const DnsResourceKey *key, DnsAnswerFlags or_flags) { + int r; + + assert(to); + assert(from); + assert(key); + + r = dns_answer_copy_by_key(to, *from, key, or_flags); + if (r < 0) + return r; + + return dns_answer_remove_by_key(from, key); +} + void dns_answer_order_by_scope(DnsAnswer *a, bool prefer_link_local) { DnsAnswerItem *items; unsigned i, start, end; @@ -539,3 +757,40 @@ int dns_answer_reserve_or_clone(DnsAnswer **a, unsigned n_free) { return 0; } + +void dns_answer_dump(DnsAnswer *answer, FILE *f) { + DnsResourceRecord *rr; + DnsAnswerFlags flags; + int ifindex; + + if (!f) + f = stdout; + + DNS_ANSWER_FOREACH_FULL(rr, ifindex, flags, answer) { + const char *t; + + fputc('\t', f); + + t = dns_resource_record_to_string(rr); + if (!t) { + log_oom(); + continue; + } + + fputs(t, f); + + if (ifindex != 0 || flags & (DNS_ANSWER_AUTHENTICATED|DNS_ANSWER_CACHEABLE|DNS_ANSWER_SHARED_OWNER)) + fputs("\t;", f); + + if (ifindex != 0) + printf(" ifindex=%i", ifindex); + if (flags & DNS_ANSWER_AUTHENTICATED) + fputs(" authenticated", f); + if (flags & DNS_ANSWER_CACHEABLE) + fputs(" cachable", f); + if (flags & DNS_ANSWER_SHARED_OWNER) + fputs(" shared-owner", f); + + fputc('\n', f); + } +} |