From 55944e5e40b1be2afc4855d8d2baf4b73d1876b5 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 10 Apr 2024 22:49:52 +0200 Subject: Adding upstream version 255.4. Signed-off-by: Daniel Baumann --- src/resolve/resolved-dns-stream.h | 128 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 128 insertions(+) create mode 100644 src/resolve/resolved-dns-stream.h (limited to 'src/resolve/resolved-dns-stream.h') diff --git a/src/resolve/resolved-dns-stream.h b/src/resolve/resolved-dns-stream.h new file mode 100644 index 0000000..ba4a59e --- /dev/null +++ b/src/resolve/resolved-dns-stream.h @@ -0,0 +1,128 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +#pragma once + +#include "sd-event.h" + +#include "ordered-set.h" +#include "socket-util.h" + +typedef struct DnsServer DnsServer; +typedef struct DnsStream DnsStream; +typedef struct DnsTransaction DnsTransaction; +typedef struct Manager Manager; +typedef struct DnsStubListenerExtra DnsStubListenerExtra; + +#include "resolved-dns-packet.h" +#include "resolved-dnstls.h" + +/* Various timeouts for establishing TCP connections. First the default time-out for that. */ +#define DNS_STREAM_DEFAULT_TIMEOUT_USEC (10 * USEC_PER_SEC) + +/* In the DNS stub, be more friendly for incoming connections, than we are to ourselves for outgoing ones */ +#define DNS_STREAM_STUB_TIMEOUT_USEC (30 * USEC_PER_SEC) + +/* In opportunistic TLS mode, lower timeouts */ +#define DNS_STREAM_OPPORTUNISTIC_TLS_TIMEOUT_USEC (3 * USEC_PER_SEC) + +/* Once connections are established apply this timeout once nothing happens anymore */ +#define DNS_STREAM_ESTABLISHED_TIMEOUT_USEC (10 * USEC_PER_SEC) + +typedef enum DnsStreamType { + DNS_STREAM_LOOKUP, /* Outgoing connection to a classic DNS server */ + DNS_STREAM_LLMNR_SEND, /* Outgoing LLMNR TCP lookup */ + DNS_STREAM_LLMNR_RECV, /* Incoming LLMNR TCP lookup */ + DNS_STREAM_STUB, /* Incoming DNS stub connection */ + _DNS_STREAM_TYPE_MAX, + _DNS_STREAM_TYPE_INVALID = -EINVAL, +} DnsStreamType; + +#define DNS_STREAM_WRITE_TLS_DATA 1 + +/* Streams are used by three subsystems: + * + * 1. The normal transaction logic when doing a DNS or LLMNR lookup via TCP + * 2. The LLMNR logic when accepting a TCP-based lookup + * 3. The DNS stub logic when accepting a TCP-based lookup + */ + +struct DnsStream { + Manager *manager; + unsigned n_ref; + + DnsStreamType type; + DnsProtocol protocol; + + int fd; + union sockaddr_union peer; + socklen_t peer_salen; + union sockaddr_union local; + socklen_t local_salen; + int ifindex; + uint32_t ttl; + bool identified; + bool packet_received; /* At least one packet is received. Used by LLMNR. */ + uint32_t requested_events; + + /* only when using TCP fast open */ + union sockaddr_union tfo_address; + socklen_t tfo_salen; + +#if ENABLE_DNS_OVER_TLS + DnsTlsStreamData dnstls_data; + uint32_t dnstls_events; +#endif + + sd_event_source *io_event_source; + sd_event_source *timeout_event_source; + + be16_t write_size, read_size; + DnsPacket *write_packet, *read_packet; + size_t n_written, n_read; + OrderedSet *write_queue; + + int (*on_packet)(DnsStream *s, DnsPacket *p); + int (*complete)(DnsStream *s, int error); + + LIST_HEAD(DnsTransaction, transactions); /* when used by the transaction logic */ + DnsServer *server; /* when used by the transaction logic */ + Set *queries; /* when used by the DNS stub logic */ + + /* used when DNS-over-TLS is enabled */ + bool encrypted:1; + + DnsStubListenerExtra *stub_listener_extra; + + LIST_FIELDS(DnsStream, streams); +}; + +int dns_stream_new( + Manager *m, + DnsStream **ret, + DnsStreamType type, + DnsProtocol protocol, + int fd, + const union sockaddr_union *tfo_address, + int (on_packet)(DnsStream*, DnsPacket*), + int (complete)(DnsStream*, int), /* optional */ + usec_t connect_timeout_usec); +#if ENABLE_DNS_OVER_TLS +int dns_stream_connect_tls(DnsStream *s, void *tls_session); +#endif +DnsStream *dns_stream_unref(DnsStream *s); +DnsStream *dns_stream_ref(DnsStream *s); + +DEFINE_TRIVIAL_CLEANUP_FUNC(DnsStream*, dns_stream_unref); + +int dns_stream_write_packet(DnsStream *s, DnsPacket *p); +ssize_t dns_stream_writev(DnsStream *s, const struct iovec *iov, size_t iovcnt, int flags); + +static inline bool DNS_STREAM_QUEUED(DnsStream *s) { + assert(s); + + if (s->fd < 0) /* already stopped? */ + return false; + + return !!s->write_packet; +} + +void dns_stream_detach(DnsStream *s); -- cgit v1.2.3