src/resolve/resolved-dns-server.h

   1 #pragma once
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2014 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include "in-addr-util.h"
  23
  24 typedef struct DnsServer DnsServer;
  25
  26 typedef enum DnsServerType {
  27         DNS_SERVER_SYSTEM,
  28         DNS_SERVER_FALLBACK,
  29         DNS_SERVER_LINK,
  30 } DnsServerType;
  31 #define _DNS_SERVER_TYPE_MAX (DNS_SERVER_LINK + 1)
  32
  33 const char* dns_server_type_to_string(DnsServerType i) _const_;
  34 DnsServerType dns_server_type_from_string(const char *s) _pure_;
  35
  36 typedef enum DnsServerFeatureLevel {
  37         DNS_SERVER_FEATURE_LEVEL_TCP,
  38         DNS_SERVER_FEATURE_LEVEL_UDP,
  39         DNS_SERVER_FEATURE_LEVEL_EDNS0,
  40         DNS_SERVER_FEATURE_LEVEL_DO,
  41         DNS_SERVER_FEATURE_LEVEL_LARGE,
  42         _DNS_SERVER_FEATURE_LEVEL_MAX,
  43         _DNS_SERVER_FEATURE_LEVEL_INVALID = -1
  44 } DnsServerFeatureLevel;
  45
  46 #define DNS_SERVER_FEATURE_LEVEL_WORST 0
  47 #define DNS_SERVER_FEATURE_LEVEL_BEST (_DNS_SERVER_FEATURE_LEVEL_MAX - 1)
  48
  49 const char* dns_server_feature_level_to_string(int i) _const_;
  50 int dns_server_feature_level_from_string(const char *s) _pure_;
  51
  52 #include "resolved-link.h"
  53 #include "resolved-manager.h"
  54
  55 struct DnsServer {
  56         Manager *manager;
  57
  58         unsigned n_ref;
  59
  60         DnsServerType type;
  61         Link *link;
  62
  63         int family;
  64         union in_addr_union address;
  65         int ifindex; /* for IPv6 link-local DNS servers */
  66
  67         char *server_string;
  68
  69         usec_t resend_timeout;
  70         usec_t max_rtt;
  71
  72         DnsServerFeatureLevel verified_feature_level;
  73         DnsServerFeatureLevel possible_feature_level;
  74
  75         size_t received_udp_packet_max;
  76
  77         unsigned n_failed_udp;
  78         unsigned n_failed_tcp;
  79
  80         bool packet_truncated:1;
  81         bool packet_bad_opt:1;
  82         bool packet_rrsig_missing:1;
  83
  84         usec_t verified_usec;
  85         usec_t features_grace_period_usec;
  86
  87         /* Whether we already warned about downgrading to non-DNSSEC mode for this server */
  88         bool warned_downgrade:1;
  89
  90         /* Used when GC'ing old DNS servers when configuration changes. */
  91         bool marked:1;
  92
  93         /* If linked is set, then this server appears in the servers linked list */
  94         bool linked:1;
  95         LIST_FIELDS(DnsServer, servers);
  96 };
  97
  98 int dns_server_new(
  99                 Manager *m,
 100                 DnsServer **ret,
 101                 DnsServerType type,
 102                 Link *link,
 103                 int family,
 104                 const union in_addr_union *address,
 105                 int ifindex);
 106
 107 DnsServer* dns_server_ref(DnsServer *s);
 108 DnsServer* dns_server_unref(DnsServer *s);
 109
 110 void dns_server_unlink(DnsServer *s);
 111 void dns_server_move_back_and_unmark(DnsServer *s);
 112
 113 void dns_server_packet_received(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t rtt, size_t size);
 114 void dns_server_packet_lost(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t usec);
 115 void dns_server_packet_truncated(DnsServer *s, DnsServerFeatureLevel level);
 116 void dns_server_packet_rrsig_missing(DnsServer *s, DnsServerFeatureLevel level);
 117 void dns_server_packet_bad_opt(DnsServer *s, DnsServerFeatureLevel level);
 118 void dns_server_packet_rcode_downgrade(DnsServer *s, DnsServerFeatureLevel level);
 119
 120 DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s);
 121
 122 int dns_server_adjust_opt(DnsServer *server, DnsPacket *packet, DnsServerFeatureLevel level);
 123
 124 const char *dns_server_string(DnsServer *server);
 125 int dns_server_ifindex(const DnsServer *s);
 126
 127 bool dns_server_dnssec_supported(DnsServer *server);
 128
 129 void dns_server_warn_downgrade(DnsServer *server);
 130
 131 bool dns_server_limited_domains(DnsServer *server);
 132
 133 DnsServer *dns_server_find(DnsServer *first, int family, const union in_addr_union *in_addr, int ifindex);
 134
 135 void dns_server_unlink_all(DnsServer *first);
 136 void dns_server_unlink_marked(DnsServer *first);
 137 void dns_server_mark_all(DnsServer *first);
 138
 139 DnsServer *manager_get_first_dns_server(Manager *m, DnsServerType t);
 140
 141 DnsServer *manager_set_dns_server(Manager *m, DnsServer *s);
 142 DnsServer *manager_get_dns_server(Manager *m);
 143 void manager_next_dns_server(Manager *m);
 144
 145 bool dns_server_address_valid(int family, const union in_addr_union *sa);
 146
 147 DnssecMode dns_server_get_dnssec_mode(DnsServer *s);
 148
 149 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsServer*, dns_server_unref);
 150
 151 extern const struct hash_ops dns_server_hash_ops;
 152
 153 void dns_server_flush_cache(DnsServer *s);
 154
 155 void dns_server_reset_features(DnsServer *s);
 156 void dns_server_reset_features_all(DnsServer *s);