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 typedef enum DnsStreamType {
   9         DNS_STREAM_LOOKUP,        /* Outgoing connection to a classic DNS server */
  10         DNS_STREAM_LLMNR_SEND,    /* Outgoing LLMNR TCP lookup */
  11         DNS_STREAM_LLMNR_RECV,    /* Incoming LLMNR TCP lookup */
  12         DNS_STREAM_STUB,          /* Incoming DNS stub connection */
  13         _DNS_STREAM_TYPE_MAX,
  14         _DNS_STREAM_TYPE_INVALID = -1,
  15 } DnsStreamType;
  16
  17 #include "resolved-dns-packet.h"
  18 #include "resolved-dns-transaction.h"
  19 #include "resolved-manager.h"
  20 #if ENABLE_DNS_OVER_TLS
  21 #include "resolved-dnstls.h"
  22 #endif
  23
  24 #define DNS_STREAM_WRITE_TLS_DATA 1
  25
  26 /* Streams are used by three subsystems:
  27  *
  28  *   1. The normal transaction logic when doing a DNS or LLMNR lookup via TCP
  29  *   2. The LLMNR logic when accepting a TCP-based lookup
  30  *   3. The DNS stub logic when accepting a TCP-based lookup
  31  */
  32
  33 struct DnsStream {
  34         Manager *manager;
  35         unsigned n_ref;
  36
  37         DnsStreamType type;
  38         DnsProtocol protocol;
  39
  40         int fd;
  41         union sockaddr_union peer;
  42         socklen_t peer_salen;
  43         union sockaddr_union local;
  44         socklen_t local_salen;
  45         int ifindex;
  46         uint32_t ttl;
  47         bool identified;
  48
  49         /* only when using TCP fast open */
  50         union sockaddr_union tfo_address;
  51         socklen_t tfo_salen;
  52
  53 #if ENABLE_DNS_OVER_TLS
  54         DnsTlsStreamData dnstls_data;
  55         int dnstls_events;
  56 #endif
  57
  58         sd_event_source *io_event_source;
  59         sd_event_source *timeout_event_source;
  60
  61         be16_t write_size, read_size;
  62         DnsPacket *write_packet, *read_packet;
  63         size_t n_written, n_read;
  64         OrderedSet *write_queue;
  65
  66         int (*on_packet)(DnsStream *s);
  67         int (*complete)(DnsStream *s, int error);
  68
  69         LIST_HEAD(DnsTransaction, transactions); /* when used by the transaction logic */
  70         DnsServer *server;                       /* when used by the transaction logic */
  71         Set *queries;                            /* when used by the DNS stub logic */
  72
  73         /* used when DNS-over-TLS is enabled */
  74         bool encrypted:1;
  75
  76         LIST_FIELDS(DnsStream, streams);
  77 };
  78
  79 int dns_stream_new(Manager *m, DnsStream **s, DnsStreamType type, DnsProtocol protocol, int fd, const union sockaddr_union *tfo_address);
  80 #if ENABLE_DNS_OVER_TLS
  81 int dns_stream_connect_tls(DnsStream *s, void *tls_session);
  82 #endif
  83 DnsStream *dns_stream_unref(DnsStream *s);
  84 DnsStream *dns_stream_ref(DnsStream *s);
  85
  86 DEFINE_TRIVIAL_CLEANUP_FUNC(DnsStream*, dns_stream_unref);
  87
  88 int dns_stream_write_packet(DnsStream *s, DnsPacket *p);
  89 ssize_t dns_stream_writev(DnsStream *s, const struct iovec *iov, size_t iovcnt, int flags);
  90
  91 static inline bool DNS_STREAM_QUEUED(DnsStream *s) {
  92         assert(s);
  93
  94         if (s->fd < 0) /* already stopped? */
  95                 return false;
  96
  97         return !!s->write_packet;
  98 }
  99
 100 DnsPacket *dns_stream_take_read_packet(DnsStream *s);
 101
 102 void dns_stream_detach(DnsStream *s);