libworker.h File Reference

This file contains the worker process or thread that performs the DNS resolving and validation. More...

#include "util/data/packed_rrset.h"

Data Structures
struct	libworker
	The library-worker status structure Internal to the worker. More...
Functions
int	libworker_bg (struct ub_ctx *ctx)
	Create a background worker.
int	libworker_fg (struct ub_ctx *ctx, struct ctx_query *q)
	Create a foreground worker.
void	libworker_alloc_cleanup (void *arg)
	cleanup the cache to remove all rrset IDs from it, arg is libworker
struct outbound_entry *	libworker_send_query (uint8_t *qname, size_t qnamelen, uint16_t qtype, uint16_t qclass, uint16_t flags, int dnssec, int want_dnssec, struct sockaddr_storage *addr, socklen_t addrlen, uint8_t *zone, size_t zonelen, struct module_qstate *q)
	Worker service routine to send serviced queries to authoritative servers.
int	libworker_handle_reply (struct comm_point *c, void *arg, int error, struct comm_reply *reply_info)
	process incoming replies from the network
int	libworker_handle_service_reply (struct comm_point *c, void *arg, int error, struct comm_reply *reply_info)
	process incoming serviced query replies from the network
void	libworker_handle_control_cmd (struct tube *tube, uint8_t *msg, size_t len, int err, void *arg)
	handle control command coming into server
void	libworker_handle_result_write (struct tube *tube, uint8_t *msg, size_t len, int err, void *arg)
	handle opportunity to write result back
void	libworker_fg_done_cb (void *arg, int rcode, ldns_buffer *buf, enum sec_status s, char *why_bogus)
	mesh callback with fg results
void	libworker_bg_done_cb (void *arg, int rcode, ldns_buffer *buf, enum sec_status s, char *why_bogus)
	mesh callback with bg results
void	libworker_enter_result (struct ub_result *res, ldns_buffer *buf, struct regional *temp, enum sec_status msg_security)
	fill result from parsed message, on error fills servfail

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Detailed Description

This file contains the worker process or thread that performs the DNS resolving and validation.

The worker is called by a procedure and if in the background continues until exit, if in the foreground returns from the procedure when done.

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Function Documentation

int libworker_bg

(

struct ub_ctx *

ctx

)

Create a background worker.

Parameters:

ctx,:

is updated with pid/tid of the background worker. a new allocation cache is obtained from ctx. It contains the threadnumber and unique id for further (shared) cache insertions.

Returns:

0 if OK, else error. Further communication is done via the pipes in ctx.

References ub_ctx::bg_pid, ub_ctx::bg_tid, ub_ctx::cfglock, ub_ctx::dothread, fatal_exit(), libworker::is_bg_thread, libworker_dobg(), libworker_setup(), ub_ctx::qq_pipe, ub_ctx::rr_pipe, libworker::thread_num, tube_close_read(), tube_close_write(), UB_FORKFAIL, UB_NOERROR, and UB_NOMEM.

Referenced by ub_resolve_async().

int libworker_fg	(	struct ub_ctx *	ctx,
		struct ctx_query *	q
	)

Create a foreground worker.

This worker will join the threadpool of resolver threads. It exits when the query answer has been obtained (or error). This routine blocks until the worker is finished.

Parameters:

ctx,:	new allocation cache obtained and returned to it.
q,:	query (result is stored in here).

Returns:

0 if finished OK, else error.

References libworker::back, libworker::base, BIT_RD, comm_base_dispatch(), libworker::env, libworker_delete(), libworker_fillup_fg(), libworker_setup(), ub_ctx::local_zones, local_zones_answer(), module_env::mesh, mesh_new_callback(), query_info::qname, regional_free_all(), module_env::scratch, sec_status_insecure, setup_qinfo_edns(), UB_INITFAIL, UB_NOERROR, UB_NOMEM, UB_SYNTAX, outside_network::udp_buff, and ctx_query::w.

Referenced by ub_resolve().

struct outbound_entry* libworker_send_query	(	uint8_t *	qname,
		size_t	qnamelen,
		uint16_t	qtype,
		uint16_t	qclass,
		uint16_t	flags,
		int	dnssec,
		int	want_dnssec,
		struct sockaddr_storage *	addr,
		socklen_t	addrlen,
		uint8_t *	zone,
		size_t	zonelen,
		struct module_qstate *	q
	)		[read]

Worker service routine to send serviced queries to authoritative servers.

Parameters:

qname,:	query name. (host order)
qnamelen,:	length in bytes of qname, including trailing 0.
qtype,:	query type. (host order)
qclass,:	query class. (host order)
flags,:	host order flags word, with opcode and CD bit.
dnssec,:	if set, EDNS record will have DO bit set.
want_dnssec,:	signatures needed.
addr,:	where to.
addrlen,:	length of addr.
zone,:	delegation point name.
zonelen,:	length of zone name wireformat dname.
q,:	wich query state to reactivate upon return.

Returns:

: false on failure (memory or socket related). no query was sent.

References libworker::back, module_env::cfg, module_qstate::env, outbound_entry_compare(), outnet_serviced_query(), module_qstate::region, regional_alloc(), config_file::ssl_upstream, config_file::tcp_upstream, outside_network::udp_buff, and module_env::worker.

void libworker_enter_result	(	struct ub_result *	res,
		ldns_buffer *	buf,
		struct regional *	temp,
		enum sec_status	msg_security
	)

fill result from parsed message, on error fills servfail

Parameters:

res,:	is clear at start, filled in at end.
buf,:	contains DNS message.
temp,:	temporary buffer for parse.
msg_security,:	security status of the DNS message. On error, the res may contain a different status (out of memory is not secure, not bogus).

References ub_result::bogus, ub_result::data, fill_res(), reply_info::flags, FLAGS_GET_RCODE, ub_result::havedata, log_err(), ub_result::nxdomain, parse_reply(), ub_result::rcode, reply_find_answer_rrset(), reply_find_final_cname_target(), sec_status_bogus, sec_status_secure, and ub_result::secure.

Referenced by libworker_fillup_fg(), and process_answer_detail().