src/resolve/resolved-dns-server.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2014 Lennart Poettering
   8 ***/
   9
  10 #include "in-addr-util.h"
  11
  12 #if HAVE_GNUTLS
  13 #include <gnutls/gnutls.h>
  14 #endif
  15
  16 typedef struct DnsServer DnsServer;
  17
  18 typedef enum DnsServerType {
  19         DNS_SERVER_SYSTEM,
  20         DNS_SERVER_FALLBACK,
  21         DNS_SERVER_LINK,
  22 } DnsServerType;
  23 #define _DNS_SERVER_TYPE_MAX (DNS_SERVER_LINK + 1)
  24
  25 const char* dns_server_type_to_string(DnsServerType i) _const_;
  26 DnsServerType dns_server_type_from_string(const char *s) _pure_;
  27
  28 typedef enum DnsServerFeatureLevel {
  29         DNS_SERVER_FEATURE_LEVEL_TCP,
  30         DNS_SERVER_FEATURE_LEVEL_UDP,
  31         DNS_SERVER_FEATURE_LEVEL_EDNS0,
  32         DNS_SERVER_FEATURE_LEVEL_TLS_PLAIN,
  33         DNS_SERVER_FEATURE_LEVEL_DO,
  34         DNS_SERVER_FEATURE_LEVEL_LARGE,
  35         DNS_SERVER_FEATURE_LEVEL_TLS_DO,
  36         _DNS_SERVER_FEATURE_LEVEL_MAX,
  37         _DNS_SERVER_FEATURE_LEVEL_INVALID = -1
  38 } DnsServerFeatureLevel;
  39
  40 #define DNS_SERVER_FEATURE_LEVEL_WORST 0
  41 #define DNS_SERVER_FEATURE_LEVEL_BEST (_DNS_SERVER_FEATURE_LEVEL_MAX - 1)
  42 #define DNS_SERVER_FEATURE_LEVEL_IS_TLS(x) IN_SET(x, DNS_SERVER_FEATURE_LEVEL_TLS_PLAIN, DNS_SERVER_FEATURE_LEVEL_TLS_DO)
  43
  44 const char* dns_server_feature_level_to_string(int i) _const_;
  45 int dns_server_feature_level_from_string(const char *s) _pure_;
  46
  47 #include "resolved-link.h"
  48 #include "resolved-manager.h"
  49
  50 struct DnsServer {
  51         Manager *manager;
  52
  53         unsigned n_ref;
  54
  55         DnsServerType type;
  56         Link *link;
  57
  58         int family;
  59         union in_addr_union address;
  60         int ifindex; /* for IPv6 link-local DNS servers */
  61
  62         char *server_string;
  63         DnsStream *stream;
  64
  65 #if HAVE_GNUTLS
  66         gnutls_certificate_credentials_t tls_cert_cred;
  67         gnutls_datum_t tls_session_data;
  68 #endif
  69
  70         DnsServerFeatureLevel verified_feature_level;
  71         DnsServerFeatureLevel possible_feature_level;
  72
  73         size_t received_udp_packet_max;
  74
  75         unsigned n_failed_udp;
  76         unsigned n_failed_tcp;
  77         unsigned n_failed_tls;
  78
  79         bool packet_truncated:1;
  80         bool packet_bad_opt:1;
  81         bool packet_rrsig_missing:1;
  82
  83         usec_t verified_usec;
  84         usec_t features_grace_period_usec;
  85
  86         /* Whether we already warned about downgrading to non-DNSSEC mode for this server */
  87         bool warned_downgrade:1;
  88
  89         /* Used when GC'ing old DNS servers when configuration changes. */
  90         bool marked:1;
  91
  92         /* If linked is set, then this server appears in the servers linked list */
  93         bool linked:1;
  94         LIST_FIELDS(DnsServer, servers);
  95 };
  96
  97 int dns_server_new(
  98                 Manager *m,
  99                 DnsServer **ret,
 100                 DnsServerType type,
 101                 Link *link,
 102                 int family,
 103                 const union in_addr_union *address,
 104                 int ifindex);
 105
 106 DnsServer* dns_server_ref(DnsServer *s);
 107 DnsServer* dns_server_unref(DnsServer *s);
 108
 109 void dns_server_unlink(DnsServer *s);
 110 void dns_server_move_back_and_unmark(DnsServer *s);
 111
 112 void dns_server_packet_received(DnsServer *s, int protocol, DnsServerFeatureLevel level, size_t size);
 113 void dns_server_packet_lost(DnsServer *s, int protocol, DnsServerFeatureLevel level, usec_t usec);
 114 void dns_server_packet_truncated(DnsServer *s, DnsServerFeatureLevel level);
 115 void dns_server_packet_rrsig_missing(DnsServer *s, DnsServerFeatureLevel level);
 116 void dns_server_packet_bad_opt(DnsServer *s, DnsServerFeatureLevel level);
 117 void dns_server_packet_rcode_downgrade(DnsServer *s, DnsServerFeatureLevel level);
 118
 119 DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s);
 120
 121 int dns_server_adjust_opt(DnsServer *server, DnsPacket *packet, DnsServerFeatureLevel level);
 122
 123 const char *dns_server_string(DnsServer *server);
 124 int dns_server_ifindex(const DnsServer *s);
 125
 126 bool dns_server_dnssec_supported(DnsServer *server);
 127
 128 void dns_server_warn_downgrade(DnsServer *server);
 129
 130 bool dns_server_limited_domains(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 DnssecMode dns_server_get_dnssec_mode(DnsServer *s);
 147 PrivateDnsMode dns_server_get_private_dns_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);
 157
 158 void dns_server_dump(DnsServer *s, FILE *f);