diff options
Diffstat (limited to 'src/resolve/resolved-dns-synthesize.c')
-rw-r--r-- | src/resolve/resolved-dns-synthesize.c | 413 |
1 files changed, 0 insertions, 413 deletions
diff --git a/src/resolve/resolved-dns-synthesize.c b/src/resolve/resolved-dns-synthesize.c deleted file mode 100644 index e3003411f7..0000000000 --- a/src/resolve/resolved-dns-synthesize.c +++ /dev/null @@ -1,413 +0,0 @@ -/*** - 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 "hostname-util.h" -#include "local-addresses.h" -#include "resolved-dns-synthesize.h" - -int dns_synthesize_ifindex(int ifindex) { - - /* When the caller asked for resolving on a specific - * interface, we synthesize the answer for that - * interface. However, if nothing specific was claimed and we - * only return localhost RRs, we synthesize the answer for - * localhost. */ - - if (ifindex > 0) - return ifindex; - - return LOOPBACK_IFINDEX; -} - -int dns_synthesize_family(uint64_t flags) { - - /* Picks an address family depending on set flags. This is - * purely for synthesized answers, where the family we return - * for the reply should match what was requested in the - * question, even though we are synthesizing the answer - * here. */ - - if (!(flags & SD_RESOLVED_DNS)) { - if (flags & (SD_RESOLVED_LLMNR_IPV4|SD_RESOLVED_MDNS_IPV4)) - return AF_INET; - if (flags & (SD_RESOLVED_LLMNR_IPV6|SD_RESOLVED_MDNS_IPV6)) - return AF_INET6; - } - - return AF_UNSPEC; -} - -DnsProtocol dns_synthesize_protocol(uint64_t flags) { - - /* Similar as dns_synthesize_family() but does this for the - * protocol. If resolving via DNS was requested, we claim it - * was DNS. Similar, if nothing specific was - * requested. However, if only resolving via LLMNR was - * requested we return that. */ - - if (flags & SD_RESOLVED_DNS) - return DNS_PROTOCOL_DNS; - if (flags & SD_RESOLVED_LLMNR) - return DNS_PROTOCOL_LLMNR; - if (flags & SD_RESOLVED_MDNS) - return DNS_PROTOCOL_MDNS; - - return DNS_PROTOCOL_DNS; -} - -static int synthesize_localhost_rr(Manager *m, const DnsResourceKey *key, int ifindex, DnsAnswer **answer) { - int r; - - assert(m); - assert(key); - assert(answer); - - r = dns_answer_reserve(answer, 2); - if (r < 0) - return r; - - if (IN_SET(key->type, DNS_TYPE_A, DNS_TYPE_ANY)) { - _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; - - rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_A, dns_resource_key_name(key)); - if (!rr) - return -ENOMEM; - - rr->a.in_addr.s_addr = htobe32(INADDR_LOOPBACK); - - r = dns_answer_add(*answer, rr, dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED); - if (r < 0) - return r; - } - - if (IN_SET(key->type, DNS_TYPE_AAAA, DNS_TYPE_ANY)) { - _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; - - rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_AAAA, dns_resource_key_name(key)); - if (!rr) - return -ENOMEM; - - rr->aaaa.in6_addr = in6addr_loopback; - - r = dns_answer_add(*answer, rr, dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED); - if (r < 0) - return r; - } - - return 0; -} - -static int answer_add_ptr(DnsAnswer **answer, const char *from, const char *to, int ifindex, DnsAnswerFlags flags) { - _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; - - rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_PTR, from); - if (!rr) - return -ENOMEM; - - rr->ptr.name = strdup(to); - if (!rr->ptr.name) - return -ENOMEM; - - return dns_answer_add(*answer, rr, ifindex, flags); -} - -static int synthesize_localhost_ptr(Manager *m, const DnsResourceKey *key, int ifindex, DnsAnswer **answer) { - int r; - - assert(m); - assert(key); - assert(answer); - - if (IN_SET(key->type, DNS_TYPE_PTR, DNS_TYPE_ANY)) { - r = dns_answer_reserve(answer, 1); - if (r < 0) - return r; - - r = answer_add_ptr(answer, dns_resource_key_name(key), "localhost", dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED); - if (r < 0) - return r; - } - - return 0; -} - -static int answer_add_addresses_rr( - DnsAnswer **answer, - const char *name, - struct local_address *addresses, - unsigned n_addresses) { - - unsigned j; - int r; - - assert(answer); - assert(name); - - r = dns_answer_reserve(answer, n_addresses); - if (r < 0) - return r; - - for (j = 0; j < n_addresses; j++) { - _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; - - r = dns_resource_record_new_address(&rr, addresses[j].family, &addresses[j].address, name); - if (r < 0) - return r; - - r = dns_answer_add(*answer, rr, addresses[j].ifindex, DNS_ANSWER_AUTHENTICATED); - if (r < 0) - return r; - } - - return 0; -} - -static int answer_add_addresses_ptr( - DnsAnswer **answer, - const char *name, - struct local_address *addresses, - unsigned n_addresses, - int af, const union in_addr_union *match) { - - unsigned j; - int r; - - assert(answer); - assert(name); - - for (j = 0; j < n_addresses; j++) { - _cleanup_(dns_resource_record_unrefp) DnsResourceRecord *rr = NULL; - - if (af != AF_UNSPEC) { - - if (addresses[j].family != af) - continue; - - if (match && !in_addr_equal(af, match, &addresses[j].address)) - continue; - } - - r = dns_answer_reserve(answer, 1); - if (r < 0) - return r; - - r = dns_resource_record_new_reverse(&rr, addresses[j].family, &addresses[j].address, name); - if (r < 0) - return r; - - r = dns_answer_add(*answer, rr, addresses[j].ifindex, DNS_ANSWER_AUTHENTICATED); - if (r < 0) - return r; - } - - return 0; -} - -static int synthesize_system_hostname_rr(Manager *m, const DnsResourceKey *key, int ifindex, DnsAnswer **answer) { - _cleanup_free_ struct local_address *addresses = NULL; - int n = 0, af; - - assert(m); - assert(key); - assert(answer); - - af = dns_type_to_af(key->type); - if (af >= 0) { - n = local_addresses(m->rtnl, ifindex, af, &addresses); - if (n < 0) - return n; - - if (n == 0) { - struct local_address buffer[2]; - - /* If we have no local addresses then use ::1 - * and 127.0.0.2 as local ones. */ - - if (af == AF_INET || af == AF_UNSPEC) - buffer[n++] = (struct local_address) { - .family = AF_INET, - .ifindex = dns_synthesize_ifindex(ifindex), - .address.in.s_addr = htobe32(0x7F000002), - }; - - if (af == AF_INET6 || af == AF_UNSPEC) - buffer[n++] = (struct local_address) { - .family = AF_INET6, - .ifindex = dns_synthesize_ifindex(ifindex), - .address.in6 = in6addr_loopback, - }; - - return answer_add_addresses_rr(answer, dns_resource_key_name(key), buffer, n); - } - } - - return answer_add_addresses_rr(answer, dns_resource_key_name(key), addresses, n); -} - -static int synthesize_system_hostname_ptr(Manager *m, int af, const union in_addr_union *address, int ifindex, DnsAnswer **answer) { - _cleanup_free_ struct local_address *addresses = NULL; - int n, r; - - assert(m); - assert(address); - assert(answer); - - if (af == AF_INET && address->in.s_addr == htobe32(0x7F000002)) { - - /* Always map the IPv4 address 127.0.0.2 to the local - * hostname, in addition to "localhost": */ - - r = dns_answer_reserve(answer, 3); - if (r < 0) - return r; - - r = answer_add_ptr(answer, "2.0.0.127.in-addr.arpa", m->llmnr_hostname, dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED); - if (r < 0) - return r; - - r = answer_add_ptr(answer, "2.0.0.127.in-addr.arpa", m->mdns_hostname, dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED); - if (r < 0) - return r; - - r = answer_add_ptr(answer, "2.0.0.127.in-addr.arpa", "localhost", dns_synthesize_ifindex(ifindex), DNS_ANSWER_AUTHENTICATED); - if (r < 0) - return r; - - return 0; - } - - n = local_addresses(m->rtnl, ifindex, af, &addresses); - if (n < 0) - return n; - - r = answer_add_addresses_ptr(answer, m->llmnr_hostname, addresses, n, af, address); - if (r < 0) - return r; - - return answer_add_addresses_ptr(answer, m->mdns_hostname, addresses, n, af, address); -} - -static int synthesize_gateway_rr(Manager *m, const DnsResourceKey *key, int ifindex, DnsAnswer **answer) { - _cleanup_free_ struct local_address *addresses = NULL; - int n = 0, af; - - assert(m); - assert(key); - assert(answer); - - af = dns_type_to_af(key->type); - if (af >= 0) { - n = local_gateways(m->rtnl, ifindex, af, &addresses); - if (n < 0) - return n; - } - - return answer_add_addresses_rr(answer, dns_resource_key_name(key), addresses, n); -} - -static int synthesize_gateway_ptr(Manager *m, int af, const union in_addr_union *address, int ifindex, DnsAnswer **answer) { - _cleanup_free_ struct local_address *addresses = NULL; - int n; - - assert(m); - assert(address); - assert(answer); - - n = local_gateways(m->rtnl, ifindex, af, &addresses); - if (n < 0) - return n; - - return answer_add_addresses_ptr(answer, "gateway", addresses, n, af, address); -} - -int dns_synthesize_answer( - Manager *m, - DnsQuestion *q, - int ifindex, - DnsAnswer **ret) { - - _cleanup_(dns_answer_unrefp) DnsAnswer *answer = NULL; - DnsResourceKey *key; - bool found = false; - int r; - - assert(m); - assert(q); - - DNS_QUESTION_FOREACH(key, q) { - union in_addr_union address; - const char *name; - int af; - - if (key->class != DNS_CLASS_IN && - key->class != DNS_CLASS_ANY) - continue; - - name = dns_resource_key_name(key); - - if (is_localhost(name)) { - - r = synthesize_localhost_rr(m, key, ifindex, &answer); - if (r < 0) - return log_error_errno(r, "Failed to synthesize localhost RRs: %m"); - - } else if (manager_is_own_hostname(m, name)) { - - r = synthesize_system_hostname_rr(m, key, ifindex, &answer); - if (r < 0) - return log_error_errno(r, "Failed to synthesize system hostname RRs: %m"); - - } else if (is_gateway_hostname(name)) { - - r = synthesize_gateway_rr(m, key, ifindex, &answer); - if (r < 0) - return log_error_errno(r, "Failed to synthesize gateway RRs: %m"); - - } else if ((dns_name_endswith(name, "127.in-addr.arpa") > 0 && dns_name_equal(name, "2.0.0.127.in-addr.arpa") == 0) || - dns_name_equal(name, "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa") > 0) { - - r = synthesize_localhost_ptr(m, key, ifindex, &answer); - if (r < 0) - return log_error_errno(r, "Failed to synthesize localhost PTR RRs: %m"); - - } else if (dns_name_address(name, &af, &address) > 0) { - - r = synthesize_system_hostname_ptr(m, af, &address, ifindex, &answer); - if (r < 0) - return log_error_errno(r, "Failed to synthesize system hostname PTR RR: %m"); - - r = synthesize_gateway_ptr(m, af, &address, ifindex, &answer); - if (r < 0) - return log_error_errno(r, "Failed to synthesize gateway hostname PTR RR: %m"); - } else - continue; - - found = true; - } - - r = found; - - if (ret) { - *ret = answer; - answer = NULL; - } - - return r; -} |