src/resolve/resolved-dns-stream.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   Copyright 2014 Lennart Poettering
   6 ***/
   7
   8 #include "socket-util.h"
   9
  10 typedef struct DnsStream DnsStream;
  11
  12 #include "resolved-dns-packet.h"
  13 #include "resolved-dns-transaction.h"
  14 #include "resolved-manager.h"
  15
  16 #if HAVE_GNUTLS
  17 #include <gnutls/gnutls.h>
  18 #endif
  19
  20 /* Streams are used by three subsystems:
  21  *
  22  *   1. The normal transaction logic when doing a DNS or LLMNR lookup via TCP
  23  *   2. The LLMNR logic when accepting a TCP-based lookup
  24  *   3. The DNS stub logic when accepting a TCP-based lookup
  25  */
  26
  27 struct DnsStream {
  28         Manager *manager;
  29         int n_ref;
  30
  31         DnsProtocol protocol;
  32
  33         int fd;
  34         union sockaddr_union peer;
  35         socklen_t peer_salen;
  36         union sockaddr_union local;
  37         socklen_t local_salen;
  38         int ifindex;
  39         uint32_t ttl;
  40         bool identified;
  41
  42         /* only when using TCP fast open */
  43         union sockaddr_union tfo_address;
  44         socklen_t tfo_salen;
  45
  46 #if HAVE_GNUTLS
  47         gnutls_session_t tls_session;
  48         int tls_handshake;
  49         bool tls_bye;
  50 #endif
  51
  52         sd_event_source *io_event_source;
  53         sd_event_source *timeout_event_source;
  54
  55         be16_t write_size, read_size;
  56         DnsPacket *write_packet, *read_packet;
  57         size_t n_written, n_read;
  58         OrderedSet *write_queue;
  59
  60         int (*on_connection)(DnsStream *s);
  61         int (*on_packet)(DnsStream *s);
  62         int (*complete)(DnsStream *s, int error);
  63
  64         LIST_HEAD(DnsTransaction, transactions); /* when used by the transaction logic */
  65         DnsServer *server;                       /* when used by the transaction logic */
  66         DnsQuery *query;             /* when used by the DNS stub logic */
  67
  68         /* used when DNS-over-TLS is enabled */
  69         bool encrypted:1;
  70
  71         LIST_FIELDS(DnsStream, streams);
  72 };
  73
  74 int dns_stream_new(Manager *m, DnsStream **s, DnsProtocol protocol, int fd, const union sockaddr_union *tfo_address);
  75 #if HAVE_GNUTLS
  76 int dns_stream_connect_tls(DnsStream *s, gnutls_session_t tls_session);
  77 #endif
  78 DnsStream *dns_stream_unref(DnsStream *s);
  79 DnsStream *dns_stream_ref(DnsStream *s);
  80
  81 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsStream*, dns_stream_unref);
  82
  83 int dns_stream_write_packet(DnsStream *s, DnsPacket *p);
  84
  85 static inline bool DNS_STREAM_QUEUED(DnsStream *s) {
  86         assert(s);
  87
  88         if (s->fd < 0) /* already stopped? */
  89                 return false;
  90
  91         return !!s->write_packet;
  92 }