src/resolve/resolved-dns-server.h

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