src/resolve/resolved-dns-stream.h

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