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_failed:1;
  81         bool packet_truncated:1;
  82         bool packet_bad_opt:1;
  83         bool packet_rrsig_missing:1;
  84
  85         usec_t verified_usec;
  86         usec_t features_grace_period_usec;
  87
  88         /* Whether we already warned about downgrading to non-DNSSEC mode for this server */
  89         bool warned_downgrade:1;
  90
  91         /* Used when GC'ing old DNS servers when configuration changes. */
  92         bool marked:1;
  93
  94         /* If linked is set, then this server appears in the servers linked list */
  95         bool linked:1;
  96         LIST_FIELDS(DnsServer, servers);
  97 };
  98
  99 int dns_server_new(
 100                 Manager *m,
 101                 DnsServer **ret,
 102                 DnsServerType type,
 103                 Link *link,
 104                 int family,
 105                 const union in_addr_union *address,
 106                 int ifindex);
 107
 108 DnsServer* dns_server_ref(DnsServer *s);
 109 DnsServer* dns_server_unref(DnsServer *s);
 110
 111 void dns_server_unlink(DnsServer *s);
 112 void dns_server_move_back_and_unmark(DnsServer *s);
 113
 114 void dns_server_packet_received(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t rtt, size_t size);
 115 void dns_server_packet_lost(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t usec);
 116 void dns_server_packet_failed(DnsServer *s, DnsServerFeatureLevel level);
 117 void dns_server_packet_truncated(DnsServer *s, DnsServerFeatureLevel level);
 118 void dns_server_packet_rrsig_missing(DnsServer *s, DnsServerFeatureLevel level);
 119 void dns_server_packet_bad_opt(DnsServer *s, DnsServerFeatureLevel level);
 120
 121 DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s);
 122
 123 int dns_server_adjust_opt(DnsServer *server, DnsPacket *packet, DnsServerFeatureLevel level);
 124
 125 const char *dns_server_string(DnsServer *server);
 126 int dns_server_ifindex(const DnsServer *s);
 127
 128 bool dns_server_dnssec_supported(DnsServer *server);
 129
 130 void dns_server_warn_downgrade(DnsServer *server);
 131
 132 DnsServer *dns_server_find(DnsServer *first, int family, const union in_addr_union *in_addr, int ifindex);
 133
 134 void dns_server_unlink_all(DnsServer *first);
 135 void dns_server_unlink_marked(DnsServer *first);
 136 void dns_server_mark_all(DnsServer *first);
 137
 138 DnsServer *manager_get_first_dns_server(Manager *m, DnsServerType t);
 139
 140 DnsServer *manager_set_dns_server(Manager *m, DnsServer *s);
 141 DnsServer *manager_get_dns_server(Manager *m);
 142 void manager_next_dns_server(Manager *m);
 143
 144 bool dns_server_address_valid(int family, const union in_addr_union *sa);
 145
 146 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsServer*, dns_server_unref);
 147
 148 extern const struct hash_ops dns_server_hash_ops;