/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2014 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ #include "alloc-util.h" #include "bus-common-errors.h" #include "bus-util.h" #include "dns-domain.h" #include "resolved-bus.h" #include "resolved-def.h" static int reply_query_state(DnsQuery *q) { _cleanup_free_ char *ip = NULL; const char *name; int r; if (q->request_hostname) name = q->request_hostname; else { r = in_addr_to_string(q->request_family, &q->request_address, &ip); if (r < 0) return r; name = ip; } switch (q->state) { case DNS_TRANSACTION_NO_SERVERS: return sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_NAME_SERVERS, "No appropriate name servers or networks for name found"); case DNS_TRANSACTION_TIMEOUT: return sd_bus_reply_method_errorf(q->request, SD_BUS_ERROR_TIMEOUT, "Query timed out"); case DNS_TRANSACTION_ATTEMPTS_MAX_REACHED: return sd_bus_reply_method_errorf(q->request, SD_BUS_ERROR_TIMEOUT, "All attempts to contact name servers or networks failed"); case DNS_TRANSACTION_INVALID_REPLY: return sd_bus_reply_method_errorf(q->request, BUS_ERROR_INVALID_REPLY, "Received invalid reply"); case DNS_TRANSACTION_RESOURCES: return sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_RESOURCES, "Not enough resources"); case DNS_TRANSACTION_ABORTED: return sd_bus_reply_method_errorf(q->request, BUS_ERROR_ABORTED, "Query aborted"); case DNS_TRANSACTION_FAILURE: { _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; if (q->answer_rcode == DNS_RCODE_NXDOMAIN) sd_bus_error_setf(&error, _BUS_ERROR_DNS "NXDOMAIN", "'%s' not found", name); else { const char *rc, *n; char p[3]; /* the rcode is 4 bits long */ rc = dns_rcode_to_string(q->answer_rcode); if (!rc) { sprintf(p, "%i", q->answer_rcode); rc = p; } n = strjoina(_BUS_ERROR_DNS, rc); sd_bus_error_setf(&error, n, "Could not resolve '%s', server or network returned error %s", name, rc); } return sd_bus_reply_method_error(q->request, &error); } case DNS_TRANSACTION_NULL: case DNS_TRANSACTION_PENDING: case DNS_TRANSACTION_SUCCESS: default: assert_not_reached("Impossible state"); } } static int append_address(sd_bus_message *reply, DnsResourceRecord *rr, int ifindex) { int r; assert(reply); assert(rr); r = sd_bus_message_open_container(reply, 'r', "iiay"); if (r < 0) return r; r = sd_bus_message_append(reply, "i", ifindex); if (r < 0) return r; if (rr->key->type == DNS_TYPE_A) { r = sd_bus_message_append(reply, "i", AF_INET); if (r < 0) return r; r = sd_bus_message_append_array(reply, 'y', &rr->a.in_addr, sizeof(struct in_addr)); } else if (rr->key->type == DNS_TYPE_AAAA) { r = sd_bus_message_append(reply, "i", AF_INET6); if (r < 0) return r; r = sd_bus_message_append_array(reply, 'y', &rr->aaaa.in6_addr, sizeof(struct in6_addr)); } else return -EAFNOSUPPORT; if (r < 0) return r; r = sd_bus_message_close_container(reply); if (r < 0) return r; return 0; } static void bus_method_resolve_hostname_complete(DnsQuery *q) { _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *cname = NULL, *canonical = NULL; _cleanup_bus_message_unref_ sd_bus_message *reply = NULL; _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; unsigned added = 0, i; int r; assert(q); if (q->state != DNS_TRANSACTION_SUCCESS) { r = reply_query_state(q); goto finish; } r = sd_bus_message_new_method_return(q->request, &reply); if (r < 0) goto finish; r = sd_bus_message_open_container(reply, 'a', "(iiay)"); if (r < 0) goto finish; if (q->answer) { answer = dns_answer_ref(q->answer); for (i = 0; i < answer->n_rrs; i++) { r = dns_question_matches_rr(q->question, answer->items[i].rr); if (r < 0) goto finish; if (r == 0) { /* Hmm, if this is not an address record, maybe it's a cname? If so, remember this */ r = dns_question_matches_cname(q->question, answer->items[i].rr); if (r < 0) goto finish; if (r > 0) cname = dns_resource_record_ref(answer->items[i].rr); continue; } r = append_address(reply, answer->items[i].rr, answer->items[i].ifindex); if (r < 0) goto finish; if (!canonical) canonical = dns_resource_record_ref(answer->items[i].rr); added ++; } } if (added == 0) { if (!cname) { r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_RR, "'%s' does not have any RR of requested type", q->request_hostname); goto finish; } /* This has a cname? Then update the query with the * new cname. */ r = dns_query_cname_redirect(q, cname); if (r < 0) { if (r == -ELOOP) r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_CNAME_LOOP, "CNAME loop on '%s'", q->request_hostname); else r = sd_bus_reply_method_errno(q->request, -r, NULL); goto finish; } /* Before we restart the query, let's see if any of * the RRs we already got already answers our query */ for (i = 0; i < answer->n_rrs; i++) { r = dns_question_matches_rr(q->question, answer->items[i].rr); if (r < 0) goto finish; if (r == 0) continue; r = append_address(reply, answer->items[i].rr, answer->items[i].ifindex); if (r < 0) goto finish; if (!canonical) canonical = dns_resource_record_ref(answer->items[i].rr); added++; } /* If we didn't find anything, then let's restart the * query, this time with the cname */ if (added <= 0) { r = dns_query_go(q); if (r < 0) { r = sd_bus_reply_method_errno(q->request, -r, NULL); goto finish; } return; } } r = sd_bus_message_close_container(reply); if (r < 0) goto finish; /* Return the precise spelling and uppercasing reported by the server */ assert(canonical); r = sd_bus_message_append(reply, "st", DNS_RESOURCE_KEY_NAME(canonical->key), SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family)); if (r < 0) goto finish; r = sd_bus_send(q->manager->bus, reply, NULL); finish: if (r < 0) { log_error_errno(r, "Failed to send hostname reply: %m"); sd_bus_reply_method_errno(q->request, -r, NULL); } dns_query_free(q); } static int check_ifindex_flags(int ifindex, uint64_t *flags, sd_bus_error *error) { assert(flags); if (ifindex < 0) return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid interface index"); if (*flags & ~SD_RESOLVED_FLAGS_ALL) return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid flags parameter"); if (*flags == 0) *flags = SD_RESOLVED_FLAGS_DEFAULT; return 0; } static int bus_method_resolve_hostname(sd_bus_message *message, void *userdata, sd_bus_error *error) { _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL; Manager *m = userdata; const char *hostname; int family, ifindex; uint64_t flags; DnsQuery *q; int r; assert(message); assert(m); r = sd_bus_message_read(message, "isit", &ifindex, &hostname, &family, &flags); if (r < 0) return r; if (!IN_SET(family, AF_INET, AF_INET6, AF_UNSPEC)) return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Unknown address family %i", family); r = dns_name_normalize(hostname, NULL); if (r < 0) return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid hostname '%s'", hostname); r = check_ifindex_flags(ifindex, &flags, error); if (r < 0) return r; question = dns_question_new(family == AF_UNSPEC ? 2 : 1); if (!question) return -ENOMEM; if (family != AF_INET6) { _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL; key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_A, hostname); if (!key) return -ENOMEM; r = dns_question_add(question, key); if (r < 0) return r; } if (family != AF_INET) { _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL; key = dns_resource_key_new(DNS_CLASS_IN, DNS_TYPE_AAAA, hostname); if (!key) return -ENOMEM; r = dns_question_add(question, key); if (r < 0) return r; } r = dns_query_new(m, &q, question, ifindex, flags); if (r < 0) return r; q->request = sd_bus_message_ref(message); q->request_family = family; q->request_hostname = hostname; q->complete = bus_method_resolve_hostname_complete; r = dns_query_bus_track(q, message); if (r < 0) return r; r = dns_query_go(q); if (r < 0) { dns_query_free(q); return r; } return 1; } static void bus_method_resolve_address_complete(DnsQuery *q) { _cleanup_bus_message_unref_ sd_bus_message *reply = NULL; _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; unsigned added = 0, i; int r; assert(q); if (q->state != DNS_TRANSACTION_SUCCESS) { r = reply_query_state(q); goto finish; } r = sd_bus_message_new_method_return(q->request, &reply); if (r < 0) goto finish; r = sd_bus_message_open_container(reply, 'a', "(is)"); if (r < 0) goto finish; if (q->answer) { answer = dns_answer_ref(q->answer); for (i = 0; i < answer->n_rrs; i++) { r = dns_question_matches_rr(q->question, answer->items[i].rr); if (r < 0) goto finish; if (r == 0) continue; r = sd_bus_message_append(reply, "(is)", answer->items[i].ifindex, answer->items[i].rr->ptr.name); if (r < 0) goto finish; added ++; } } if (added == 0) { _cleanup_free_ char *ip = NULL; in_addr_to_string(q->request_family, &q->request_address, &ip); r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_RR, "Address '%s' does not have any RR of requested type", ip); goto finish; } r = sd_bus_message_close_container(reply); if (r < 0) goto finish; r = sd_bus_message_append(reply, "t", SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family)); if (r < 0) goto finish; r = sd_bus_send(q->manager->bus, reply, NULL); finish: if (r < 0) { log_error_errno(r, "Failed to send address reply: %m"); sd_bus_reply_method_errno(q->request, -r, NULL); } dns_query_free(q); } static int bus_method_resolve_address(sd_bus_message *message, void *userdata, sd_bus_error *error) { _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL; _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL; _cleanup_free_ char *reverse = NULL; Manager *m = userdata; int family, ifindex; uint64_t flags; const void *d; DnsQuery *q; size_t sz; int r; assert(message); assert(m); r = sd_bus_message_read(message, "ii", &ifindex, &family); if (r < 0) return r; if (!IN_SET(family, AF_INET, AF_INET6)) return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Unknown address family %i", family); r = sd_bus_message_read_array(message, 'y', &d, &sz); if (r < 0) return r; if (sz != FAMILY_ADDRESS_SIZE(family)) return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid address size"); r = sd_bus_message_read(message, "t", &flags); if (r < 0) return r; r = check_ifindex_flags(ifindex, &flags, error); if (r < 0) return r; r = dns_name_reverse(family, d, &reverse); if (r < 0) return r; question = dns_question_new(1); if (!question) return -ENOMEM; key = dns_resource_key_new_consume(DNS_CLASS_IN, DNS_TYPE_PTR, reverse); if (!key) return -ENOMEM; reverse = NULL; r = dns_question_add(question, key); if (r < 0) return r; r = dns_query_new(m, &q, question, ifindex, flags); if (r < 0) return r; q->request = sd_bus_message_ref(message); q->request_family = family; memcpy(&q->request_address, d, sz); q->complete = bus_method_resolve_address_complete; r = dns_query_bus_track(q, message); if (r < 0) return r; r = dns_query_go(q); if (r < 0) { dns_query_free(q); return r; } return 1; } static void bus_method_resolve_record_complete(DnsQuery *q) { _cleanup_bus_message_unref_ sd_bus_message *reply = NULL; _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; unsigned added = 0, i; int r; assert(q); if (q->state != DNS_TRANSACTION_SUCCESS) { r = reply_query_state(q); goto finish; } r = sd_bus_message_new_method_return(q->request, &reply); if (r < 0) goto finish; r = sd_bus_message_open_container(reply, 'a', "(iqqay)"); if (r < 0) goto finish; if (q->answer) { answer = dns_answer_ref(q->answer); for (i = 0; i < answer->n_rrs; i++) { _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; size_t start; r = dns_question_matches_rr(q->question, answer->items[i].rr); if (r < 0) goto finish; if (r == 0) continue; r = dns_packet_new(&p, DNS_PROTOCOL_DNS, 0); if (r < 0) goto finish; p->refuse_compression = true; r = dns_packet_append_rr(p, answer->items[i].rr, &start); if (r < 0) goto finish; r = sd_bus_message_open_container(reply, 'r', "iqqay"); if (r < 0) goto finish; r = sd_bus_message_append(reply, "iqq", answer->items[i].ifindex, answer->items[i].rr->key->class, answer->items[i].rr->key->type); if (r < 0) goto finish; r = sd_bus_message_append_array(reply, 'y', DNS_PACKET_DATA(p) + start, p->size - start); if (r < 0) goto finish; r = sd_bus_message_close_container(reply); if (r < 0) goto finish; added ++; } } if (added <= 0) { r = sd_bus_reply_method_errorf(q->request, BUS_ERROR_NO_SUCH_RR, "Name '%s' does not have any RR of the requested type", q->request_hostname); goto finish; } r = sd_bus_message_close_container(reply); if (r < 0) goto finish; r = sd_bus_message_append(reply, "t", SD_RESOLVED_FLAGS_MAKE(q->answer_protocol, q->answer_family)); if (r < 0) goto finish; r = sd_bus_send(q->manager->bus, reply, NULL); finish: if (r < 0) { log_error_errno(r, "Failed to send record reply: %m"); sd_bus_reply_method_errno(q->request, -r, NULL); } dns_query_free(q); } static int bus_method_resolve_record(sd_bus_message *message, void *userdata, sd_bus_error *error) { _cleanup_(dns_resource_key_unrefp) DnsResourceKey *key = NULL; _cleanup_(dns_question_unrefp) DnsQuestion *question = NULL; Manager *m = userdata; uint16_t class, type; const char *name; int r, ifindex; uint64_t flags; DnsQuery *q; assert(message); assert(m); r = sd_bus_message_read(message, "isqqt", &ifindex, &name, &class, &type, &flags); if (r < 0) return r; r = dns_name_normalize(name, NULL); if (r < 0) return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid name '%s'", name); r = check_ifindex_flags(ifindex, &flags, error); if (r < 0) return r; question = dns_question_new(1); if (!question) return -ENOMEM; key = dns_resource_key_new(class, type, name); if (!key) return -ENOMEM; r = dns_question_add(question, key); if (r < 0) return r; r = dns_query_new(m, &q, question, ifindex, flags); if (r < 0) return r; q->request = sd_bus_message_ref(message); q->request_hostname = name; q->complete = bus_method_resolve_record_complete; r = dns_query_bus_track(q, message); if (r < 0) return r; r = dns_query_go(q); if (r < 0) { dns_query_free(q); return r; } return 1; } static const sd_bus_vtable resolve_vtable[] = { SD_BUS_VTABLE_START(0), SD_BUS_METHOD("ResolveHostname", "isit", "a(iiay)st", bus_method_resolve_hostname, SD_BUS_VTABLE_UNPRIVILEGED), SD_BUS_METHOD("ResolveAddress", "iiayt", "a(is)t", bus_method_resolve_address, SD_BUS_VTABLE_UNPRIVILEGED), SD_BUS_METHOD("ResolveRecord", "isqqt", "a(iqqay)t", bus_method_resolve_record, SD_BUS_VTABLE_UNPRIVILEGED), SD_BUS_VTABLE_END, }; static int on_bus_retry(sd_event_source *s, usec_t usec, void *userdata) { Manager *m = userdata; assert(s); assert(m); m->bus_retry_event_source = sd_event_source_unref(m->bus_retry_event_source); manager_connect_bus(m); return 0; } static int match_prepare_for_sleep(sd_bus_message *message, void *userdata, sd_bus_error *ret_error) { Manager *m = userdata; int b, r; assert(message); assert(m); r = sd_bus_message_read(message, "b", &b); if (r < 0) { log_debug_errno(r, "Failed to parse PrepareForSleep signal: %m"); return 0; } if (b) return 0; log_debug("Coming back from suspend, verifying all RRs..."); manager_verify_all(m); return 0; } int manager_connect_bus(Manager *m) { int r; assert(m); if (m->bus) return 0; r = sd_bus_default_system(&m->bus); if (r < 0) { /* We failed to connect? Yuck, we must be in early * boot. Let's try in 5s again. As soon as we have * kdbus we can stop doing this... */ log_debug_errno(r, "Failed to connect to bus, trying again in 5s: %m"); r = sd_event_add_time(m->event, &m->bus_retry_event_source, CLOCK_MONOTONIC, now(CLOCK_MONOTONIC) + 5*USEC_PER_SEC, 0, on_bus_retry, m); if (r < 0) return log_error_errno(r, "Failed to install bus reconnect time event: %m"); return 0; } r = sd_bus_add_object_vtable(m->bus, NULL, "/org/freedesktop/resolve1", "org.freedesktop.resolve1.Manager", resolve_vtable, m); if (r < 0) return log_error_errno(r, "Failed to register object: %m"); r = sd_bus_request_name(m->bus, "org.freedesktop.resolve1", 0); if (r < 0) return log_error_errno(r, "Failed to register name: %m"); r = sd_bus_attach_event(m->bus, m->event, 0); if (r < 0) return log_error_errno(r, "Failed to attach bus to event loop: %m"); r = sd_bus_add_match(m->bus, &m->prepare_for_sleep_slot, "type='signal'," "sender='org.freedesktop.login1'," "interface='org.freedesktop.login1.Manager'," "member='PrepareForSleep'," "path='/org/freedesktop/login1'", match_prepare_for_sleep, m); if (r < 0) log_error_errno(r, "Failed to add match for PrepareForSleep: %m"); return 0; }