src/resolve/resolved-dns-server.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   Copyright 2014 Lennart Poettering
   6 ***/
   7
   8 #include "in-addr-util.h"
   9
  10 #if HAVE_GNUTLS
  11 #include <gnutls/gnutls.h>
  12 #endif
  13
  14 typedef struct DnsServer DnsServer;
  15
  16 typedef enum DnsServerType {
  17         DNS_SERVER_SYSTEM,
  18         DNS_SERVER_FALLBACK,
  19         DNS_SERVER_LINK,
  20 } DnsServerType;
  21 #define _DNS_SERVER_TYPE_MAX (DNS_SERVER_LINK + 1)
  22
  23 const char* dns_server_type_to_string(DnsServerType i) _const_;
  24 DnsServerType dns_server_type_from_string(const char *s) _pure_;
  25
  26 typedef enum DnsServerFeatureLevel {
  27         DNS_SERVER_FEATURE_LEVEL_TCP,
  28         DNS_SERVER_FEATURE_LEVEL_UDP,
  29         DNS_SERVER_FEATURE_LEVEL_EDNS0,
  30         DNS_SERVER_FEATURE_LEVEL_TLS_PLAIN,
  31         DNS_SERVER_FEATURE_LEVEL_DO,
  32         DNS_SERVER_FEATURE_LEVEL_LARGE,
  33         DNS_SERVER_FEATURE_LEVEL_TLS_DO,
  34         _DNS_SERVER_FEATURE_LEVEL_MAX,
  35         _DNS_SERVER_FEATURE_LEVEL_INVALID = -1
  36 } DnsServerFeatureLevel;
  37
  38 #define DNS_SERVER_FEATURE_LEVEL_WORST 0
  39 #define DNS_SERVER_FEATURE_LEVEL_BEST (_DNS_SERVER_FEATURE_LEVEL_MAX - 1)
  40 #define DNS_SERVER_FEATURE_LEVEL_IS_TLS(x) IN_SET(x, DNS_SERVER_FEATURE_LEVEL_TLS_PLAIN, DNS_SERVER_FEATURE_LEVEL_TLS_DO)
  41
  42 const char* dns_server_feature_level_to_string(int i) _const_;
  43 int dns_server_feature_level_from_string(const char *s) _pure_;
  44
  45 #include "resolved-link.h"
  46 #include "resolved-manager.h"
  47
  48 struct DnsServer {
  49         Manager *manager;
  50
  51         unsigned n_ref;
  52
  53         DnsServerType type;
  54         Link *link;
  55
  56         int family;
  57         union in_addr_union address;
  58         int ifindex; /* for IPv6 link-local DNS servers */
  59
  60         char *server_string;
  61         DnsStream *stream;
  62
  63 #if HAVE_GNUTLS
  64         gnutls_certificate_credentials_t tls_cert_cred;
  65         gnutls_datum_t tls_session_data;
  66 #endif
  67
  68         DnsServerFeatureLevel verified_feature_level;
  69         DnsServerFeatureLevel possible_feature_level;
  70
  71         size_t received_udp_packet_max;
  72
  73         unsigned n_failed_udp;
  74         unsigned n_failed_tcp;
  75         unsigned n_failed_tls;
  76
  77         bool packet_truncated:1;
  78         bool packet_bad_opt:1;
  79         bool packet_rrsig_missing:1;
  80
  81         usec_t verified_usec;
  82         usec_t features_grace_period_usec;
  83
  84         /* Whether we already warned about downgrading to non-DNSSEC mode for this server */
  85         bool warned_downgrade:1;
  86
  87         /* Used when GC'ing old DNS servers when configuration changes. */
  88         bool marked:1;
  89
  90         /* If linked is set, then this server appears in the servers linked list */
  91         bool linked:1;
  92         LIST_FIELDS(DnsServer, servers);
  93 };
  94
  95 int dns_server_new(
  96                 Manager *m,
  97                 DnsServer **ret,
  98                 DnsServerType type,
  99                 Link *link,
 100                 int family,
 101                 const union in_addr_union *address,
 102                 int ifindex);
 103
 104 DnsServer* dns_server_ref(DnsServer *s);
 105 DnsServer* dns_server_unref(DnsServer *s);
 106
 107 void dns_server_unlink(DnsServer *s);
 108 void dns_server_move_back_and_unmark(DnsServer *s);
 109
 110 void dns_server_packet_received(DnsServer *s, int protocol, DnsServerFeatureLevel level, size_t size);
 111 void dns_server_packet_lost(DnsServer *s, int protocol, DnsServerFeatureLevel level);
 112 void dns_server_packet_truncated(DnsServer *s, DnsServerFeatureLevel level);
 113 void dns_server_packet_rrsig_missing(DnsServer *s, DnsServerFeatureLevel level);
 114 void dns_server_packet_bad_opt(DnsServer *s, DnsServerFeatureLevel level);
 115 void dns_server_packet_rcode_downgrade(DnsServer *s, DnsServerFeatureLevel level);
 116
 117 DnsServerFeatureLevel dns_server_possible_feature_level(DnsServer *s);
 118
 119 int dns_server_adjust_opt(DnsServer *server, DnsPacket *packet, DnsServerFeatureLevel level);
 120
 121 const char *dns_server_string(DnsServer *server);
 122 int dns_server_ifindex(const DnsServer *s);
 123
 124 bool dns_server_dnssec_supported(DnsServer *server);
 125
 126 void dns_server_warn_downgrade(DnsServer *server);
 127
 128 bool dns_server_limited_domains(DnsServer *server);
 129
 130 DnsServer *dns_server_find(DnsServer *first, int family, const union in_addr_union *in_addr, int ifindex);
 131
 132 void dns_server_unlink_all(DnsServer *first);
 133 void dns_server_unlink_marked(DnsServer *first);
 134 void dns_server_mark_all(DnsServer *first);
 135
 136 DnsServer *manager_get_first_dns_server(Manager *m, DnsServerType t);
 137
 138 DnsServer *manager_set_dns_server(Manager *m, DnsServer *s);
 139 DnsServer *manager_get_dns_server(Manager *m);
 140 void manager_next_dns_server(Manager *m);
 141
 142 bool dns_server_address_valid(int family, const union in_addr_union *sa);
 143
 144 DnssecMode dns_server_get_dnssec_mode(DnsServer *s);
 145 DnsOverTlsMode dns_server_get_dns_over_tls_mode(DnsServer *s);
 146
 147 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsServer*, dns_server_unref);
 148
 149 extern const struct hash_ops dns_server_hash_ops;
 150
 151 void dns_server_flush_cache(DnsServer *s);
 152
 153 void dns_server_reset_features(DnsServer *s);
 154 void dns_server_reset_features_all(DnsServer *s);
 155
 156 void dns_server_dump(DnsServer *s, FILE *f);