X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fresolve%2Fresolved-dns-zone.c;h=b577fd6cc6892c215b5dfaed80e158e1b1f5d797;hp=2325ddfe7fc51c3f9639540c160a072a3681b515;hb=de292aa1dd1942e151ff034fcb88504a86742f97;hpb=623a4c97b9175f95c4b1c6fc34e36c56f1e4ddbf diff --git a/src/resolve/resolved-dns-zone.c b/src/resolve/resolved-dns-zone.c index 2325ddfe7..b577fd6cc 100644 --- a/src/resolve/resolved-dns-zone.c +++ b/src/resolve/resolved-dns-zone.c @@ -28,20 +28,27 @@ /* Never allow more than 1K entries */ #define ZONE_MAX 1024 -typedef struct DnsZoneItem DnsZoneItem; +static void dns_zone_item_probe_stop(DnsZoneItem *i) { + DnsTransaction *t; + assert(i); -struct DnsZoneItem { - DnsResourceRecord *rr; - bool verified; - LIST_FIELDS(DnsZoneItem, by_key); - LIST_FIELDS(DnsZoneItem, by_name); -}; + if (!i->probe_transaction) + return; + + t = i->probe_transaction; + i->probe_transaction = NULL; + + set_remove(t->zone_items, i); + dns_transaction_gc(t); +} static void dns_zone_item_free(DnsZoneItem *i) { if (!i) return; + dns_zone_item_probe_stop(i); dns_resource_record_unref(i->rr); + free(i); } @@ -157,14 +164,81 @@ static int dns_zone_link_item(DnsZone *z, DnsZoneItem *i) { return 0; } -int dns_zone_put(DnsZone *z, DnsResourceRecord *rr) { +static int dns_zone_item_probe_start(DnsZoneItem *i) { + _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL; + _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL; + DnsTransaction *t; + int r; + + assert(i); + + if (i->probe_transaction) + return 0; + + key = dns_resource_key_new(i->rr->key->class, DNS_TYPE_ANY, DNS_RESOURCE_KEY_NAME(i->rr->key)); + if (!key) + return -ENOMEM; + + question = dns_question_new(1); + if (!question) + return -ENOMEM; + + r = dns_question_add(question, key); + if (r < 0) + return r; + + t = dns_scope_find_transaction(i->scope, question); + if (!t) { + r = dns_transaction_new(&t, i->scope, question); + if (r < 0) + return r; + } + + r = set_ensure_allocated(&t->zone_items, NULL, NULL); + if (r < 0) + goto gc; + + r = set_put(t->zone_items, i); + if (r < 0) + goto gc; + + i->probe_transaction = t; + + if (t->state == DNS_TRANSACTION_NULL) { + + i->block_ready++; + r = dns_transaction_go(t); + i->block_ready--; + + if (r < 0) { + dns_zone_item_probe_stop(i); + return r; + } + } + + dns_zone_item_ready(i); + + return 0; + +gc: + dns_transaction_gc(t); + return r; +} + +int dns_zone_put(DnsZone *z, DnsScope *s, DnsResourceRecord *rr, bool probe) { _cleanup_(dns_zone_item_freep) DnsZoneItem *i = NULL; DnsZoneItem *existing; int r; assert(z); + assert(s); assert(rr); + if (rr->key->class == DNS_CLASS_ANY) + return -EINVAL; + if (rr->key->type == DNS_TYPE_ANY) + return -EINVAL; + existing = dns_zone_get(z, rr); if (existing) return 0; @@ -177,68 +251,258 @@ int dns_zone_put(DnsZone *z, DnsResourceRecord *rr) { if (!i) return -ENOMEM; + i->scope = s; i->rr = dns_resource_record_ref(rr); + i->probing_enabled = probe; r = dns_zone_link_item(z, i); if (r < 0) return r; + if (probe) { + r = dns_zone_item_probe_start(i); + if (r < 0) { + dns_zone_item_remove_and_free(z, i); + i = NULL; + return r; + } + + i->state = DNS_ZONE_ITEM_PROBING; + } else + i->state = DNS_ZONE_ITEM_ESTABLISHED; + i = NULL; return 0; } -int dns_zone_lookup(DnsZone *z, DnsQuestion *q, DnsAnswer **ret) { - _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; +int dns_zone_lookup(DnsZone *z, DnsQuestion *q, DnsAnswer **ret_answer, DnsAnswer **ret_soa, bool *ret_tentative) { + _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL, *soa = NULL; + unsigned i, n_answer = 0, n_soa = 0; + bool tentative = true; int r; - unsigned i, n = 0; - bool has_other_rrs = false; assert(z); assert(q); - assert(ret); + assert(ret_answer); + assert(ret_soa); if (q->n_keys <= 0) { - *ret = NULL; + *ret_answer = NULL; + *ret_soa = NULL; + + if (ret_tentative) + *ret_tentative = false; + return 0; } + /* First iteration, count what we have */ for (i = 0; i < q->n_keys; i++) { - DnsZoneItem *j; + DnsZoneItem *j, *first; + + if (q->keys[i]->type == DNS_TYPE_ANY || + q->keys[i]->class == DNS_CLASS_ANY) { + bool found = false, added = false; + int k; + + /* If this is a generic match, then we have to + * go through the list by the name and look + * for everything manually */ + + first = hashmap_get(z->by_name, DNS_RESOURCE_KEY_NAME(q->keys[i])); + LIST_FOREACH(by_name, j, first) { + if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING)) + continue; + + found = true; + + k = dns_resource_key_match_rr(q->keys[i], j->rr); + if (k < 0) + return k; + if (k > 0) { + n_answer++; + added = true; + } + + } + + if (found && !added) + n_soa++; + + } else { + bool found = false; + + /* If this is a specific match, then look for + * the right key immediately */ + + first = hashmap_get(z->by_key, q->keys[i]); + LIST_FOREACH(by_key, j, first) { + if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING)) + continue; + + found = true; + n_answer++; + } + + if (!found) { + first = hashmap_get(z->by_name, DNS_RESOURCE_KEY_NAME(q->keys[i])); + LIST_FOREACH(by_name, j, first) { + if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING)) + continue; + + n_soa++; + break; + } + } + } + } - j = hashmap_get(z->by_key, q->keys[i]); - if (!j) { - if (hashmap_get(z->by_name, DNS_RESOURCE_KEY_NAME(q->keys[i]))) - has_other_rrs = true; + if (n_answer <= 0 && n_soa <= 0) { + *ret_answer = NULL; + *ret_soa = NULL; - continue; - } + if (ret_tentative) + *ret_tentative = false; - LIST_FOREACH(by_name, j, j) - n++; + return 0; } - if (n <= 0) { - *ret = NULL; - return has_other_rrs; + if (n_answer > 0) { + answer = dns_answer_new(n_answer); + if (!answer) + return -ENOMEM; } - answer = dns_answer_new(n); - if (!answer) - return -ENOMEM; + if (n_soa > 0) { + soa = dns_answer_new(n_soa); + if (!soa) + return -ENOMEM; + } + /* Second iteration, actually add the RRs to the answers */ for (i = 0; i < q->n_keys; i++) { - DnsZoneItem *j; - - j = hashmap_get(z->by_key, q->keys[i]); - LIST_FOREACH(by_key, j, j) { - r = dns_answer_add(answer, j->rr); - if (r < 0) - return r; + DnsZoneItem *j, *first; + + if (q->keys[i]->type == DNS_TYPE_ANY || + q->keys[i]->class == DNS_CLASS_ANY) { + bool found = false, added = false; + int k; + + first = hashmap_get(z->by_name, DNS_RESOURCE_KEY_NAME(q->keys[i])); + LIST_FOREACH(by_name, j, first) { + if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING)) + continue; + + found = true; + + if (j->state != DNS_ZONE_ITEM_PROBING) + tentative = false; + + k = dns_resource_key_match_rr(q->keys[i], j->rr); + if (k < 0) + return k; + if (k > 0) { + r = dns_answer_add(answer, j->rr); + if (r < 0) + return r; + + added = true; + } + } + + if (found && !added) { + r = dns_answer_add_soa(soa, DNS_RESOURCE_KEY_NAME(q->keys[i]), LLMNR_DEFAULT_TTL); + if (r < 0) + return r; + } + } else { + bool found = false; + + first = hashmap_get(z->by_key, q->keys[i]); + LIST_FOREACH(by_key, j, first) { + if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING)) + continue; + + found = true; + + if (j->state != DNS_ZONE_ITEM_PROBING) + tentative = false; + + r = dns_answer_add(answer, j->rr); + if (r < 0) + return r; + } + + if (!found) { + bool add_soa = false; + + first = hashmap_get(z->by_name, DNS_RESOURCE_KEY_NAME(q->keys[i])); + LIST_FOREACH(by_name, j, first) { + if (!IN_SET(j->state, DNS_ZONE_ITEM_PROBING, DNS_ZONE_ITEM_ESTABLISHED, DNS_ZONE_ITEM_VERIFYING)) + continue; + + if (j->state != DNS_ZONE_ITEM_PROBING) + tentative = false; + + add_soa = true; + } + + if (add_soa) { + r = dns_answer_add_soa(soa, DNS_RESOURCE_KEY_NAME(q->keys[i]), LLMNR_DEFAULT_TTL); + if (r < 0) + return r; + } + } } } - *ret = answer; + *ret_answer = answer; answer = NULL; + *ret_soa = soa; + soa = NULL; + + if (ret_tentative) + *ret_tentative = tentative; + return 1; } + +void dns_zone_item_conflict(DnsZoneItem *i) { + _cleanup_free_ char *pretty = NULL; + + assert(i); + + dns_resource_record_to_string(i->rr, &pretty); + log_info("Detected conflict on %s", strna(pretty)); + + /* Withdraw the conflict item */ + i->state = DNS_ZONE_ITEM_WITHDRAWN; + + /* Maybe change the hostname */ + if (dns_name_equal(i->scope->manager->hostname, DNS_RESOURCE_KEY_NAME(i->rr->key)) > 0) + manager_next_hostname(i->scope->manager); +} + +void dns_zone_item_ready(DnsZoneItem *i) { + assert(i); + assert(i->probe_transaction); + + if (i->block_ready > 0) + return; + + if (IN_SET(i->probe_transaction->state, DNS_TRANSACTION_NULL, DNS_TRANSACTION_PENDING)) + return; + + if (i->probe_transaction->state != DNS_TRANSACTION_SUCCESS) { + _cleanup_free_ char *pretty = NULL; + + dns_resource_record_to_string(i->rr, &pretty); + log_debug("Record %s successfully probed.", strna(pretty)); + + dns_zone_item_probe_stop(i); + i->state = DNS_ZONE_ITEM_ESTABLISHED; + + } else + dns_zone_item_conflict(i); +}