worker.h 6.70 KiB
/* Copyright (C) 2014-2017 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
* SPDX-License-Identifier: GPL-3.0-or-later
*/
#pragma once
#include "daemon/engine.h"
#include "lib/generic/array.h"
#include "lib/generic/map.h"
/** Query resolution task (opaque). */
struct qr_task;
/** Worker state (opaque). */
struct worker_ctx;
/** Transport session (opaque). */
struct session;
/** Zone import context (opaque). */
struct zone_import_ctx;
/** Data about the communication (defined in io.h). */
struct io_comm_data;
/** Pointer to the singleton worker. NULL if not initialized. */
KR_EXPORT extern struct worker_ctx *the_worker;
/** Create and initialize the worker.
* \return error code (ENOMEM) */
int worker_init(struct engine *engine, int worker_count);
/** Destroy the worker (free memory). */
void worker_deinit(void);
/**
* Process an incoming packet (query from a client or answer from upstream).
*
* @param session session the packet came from, or NULL (not from network)
* @param comm IO communication data (see `struct io_comm_data` docs)
* @param eth_* MAC addresses or NULL (they're useful for XDP)
* @param pkt the packet, or NULL (an error from the transport layer)
* @return 0 or an error code
*/
int worker_submit(struct session *session, struct io_comm_data *comm,
const uint8_t *eth_from, const uint8_t *eth_to, knot_pkt_t *pkt);
/**
* End current DNS/TCP session, this disassociates pending tasks from this session
* which may be freely closed afterwards.
*/
int worker_end_tcp(struct session *session);
KR_EXPORT knot_pkt_t *worker_resolve_mk_pkt_dname(knot_dname_t *qname, uint16_t qtype, uint16_t qclass,
const struct kr_qflags *options);
/**
* Create a packet suitable for worker_resolve_start(). All in malloc() memory.
*/
KR_EXPORT knot_pkt_t *
worker_resolve_mk_pkt(const char *qname_str, uint16_t qtype, uint16_t qclass,
const struct kr_qflags *options);
/**
* Start query resolution with given query.
*
* @return task or NULL
*/
KR_EXPORT struct qr_task *
worker_resolve_start(knot_pkt_t *query, struct kr_qflags options);
/**
* Execute a request with given query. * It expects task to be created with \fn worker_resolve_start.
*
* @return 0 or an error code
*/
KR_EXPORT int worker_resolve_exec(struct qr_task *task, knot_pkt_t *query);
/** @return struct kr_request associated with opaque task */
struct kr_request *worker_task_request(struct qr_task *task);
int worker_task_step(struct qr_task *task, const struct sockaddr *packet_source,
knot_pkt_t *packet);
int worker_task_numrefs(const struct qr_task *task);
/** Finalize given task */
int worker_task_finalize(struct qr_task *task, int state);
void worker_task_complete(struct qr_task *task);
void worker_task_ref(struct qr_task *task);
void worker_task_unref(struct qr_task *task);
void worker_task_timeout_inc(struct qr_task *task);
int worker_add_tcp_connected(struct worker_ctx *worker,
const struct sockaddr *addr,
struct session *session);
int worker_del_tcp_connected(struct worker_ctx *worker,
const struct sockaddr *addr);
int worker_del_tcp_waiting(struct worker_ctx *worker,
const struct sockaddr* addr);
struct session* worker_find_tcp_waiting(struct worker_ctx *worker,
const struct sockaddr* addr);
struct session* worker_find_tcp_connected(struct worker_ctx *worker,
const struct sockaddr* addr);
knot_pkt_t *worker_task_get_pktbuf(const struct qr_task *task);
struct request_ctx *worker_task_get_request(struct qr_task *task);
/** Note: source session is NULL in case the request hasn't come over network. */
KR_EXPORT struct session *worker_request_get_source_session(const struct kr_request *req);
uint16_t worker_task_pkt_get_msgid(struct qr_task *task);
void worker_task_pkt_set_msgid(struct qr_task *task, uint16_t msgid);
uint64_t worker_task_creation_time(struct qr_task *task);
void worker_task_subreq_finalize(struct qr_task *task);
bool worker_task_finished(struct qr_task *task);
/** To be called after sending a DNS message. It mainly deals with cleanups. */
int qr_task_on_send(struct qr_task *task, const uv_handle_t *handle, int status);
/** Various worker statistics. Sync with wrk_stats() */
struct worker_stats {
size_t queries; /**< Total number of requests (from clients and internal ones). */
size_t concurrent; /**< The number of requests currently in processing. */
size_t rconcurrent; /*< TODO: remove? I see no meaningful difference from .concurrent. */
size_t dropped; /**< The number of requests dropped due to being badly formed. See #471. */
size_t timeout; /**< Number of outbound queries that timed out. */
size_t udp; /**< Number of outbound queries over UDP. */
size_t tcp; /**< Number of outbound queries over TCP (excluding TLS). */
size_t tls; /**< Number of outbound queries over TLS. */
size_t ipv4; /**< Number of outbound queries over IPv4.*/
size_t ipv6; /**< Number of outbound queries over IPv6. */
size_t err_udp; /**< Total number of write errors for UDP transport. */
size_t err_tcp; /**< Total number of write errors for TCP transport. */
size_t err_tls; /**< Total number of write errors for TLS transport. */
size_t err_http; /**< Total number of write errors for HTTP(S) transport. */};
/** @cond internal */
/** Number of request within timeout window. */
#define MAX_PENDING 4
/** Maximum response time from TCP upstream, milliseconds */
#define MAX_TCP_INACTIVITY (KR_RESOLVE_TIME_LIMIT + KR_CONN_RTT_MAX)
#ifndef RECVMMSG_BATCH /* see check_bufsize() */
#define RECVMMSG_BATCH 1
#endif
/** Freelist of available mempools. */
typedef array_t(struct mempool *) mp_freelist_t;
/** List of query resolution tasks. */
typedef array_t(struct qr_task *) qr_tasklist_t;
/** List of HTTP header names. */
typedef array_t(const char *) doh_headerlist_t;
/** \details Worker state is meant to persist during the whole life of daemon. */
struct worker_ctx {
struct engine *engine;
uv_loop_t *loop;
int count; /** unreliable, does not count systemd instance, do not use */
int vars_table_ref;
unsigned tcp_pipeline_max;
/** Addresses to bind for outgoing connections or AF_UNSPEC. */
struct sockaddr_in out_addr4;
struct sockaddr_in6 out_addr6;
uint8_t wire_buf[RECVMMSG_BATCH * KNOT_WIRE_MAX_PKTSIZE];
struct worker_stats stats;
bool too_many_open;
size_t rconcurrent_highwatermark;
/** List of active outbound TCP sessions */
map_t tcp_connected;
/** List of outbound TCP sessions waiting to be accepted */
map_t tcp_waiting;
/** Subrequest leaders (struct qr_task*), indexed by qname+qtype+qclass. */
trie_t *subreq_out;
mp_freelist_t pool_mp;
knot_mm_t pkt_pool;
unsigned int next_request_uid;
/* HTTP Headers for DoH. */
doh_headerlist_t doh_qry_headers;
};
/** @endcond */