A brief file description. More...

#include "P_DNS.h"
#include <ts/ink_inet.h>

Include dependency graph for DNS.cc:

Defines
#define	SRV_COST (RRFIXEDSZ+0)
#define	SRV_WEIGHT (RRFIXEDSZ+2)
#define	SRV_PORT (RRFIXEDSZ+4)
#define	SRV_SERVER (RRFIXEDSZ+6)
#define	SRV_FIXEDSZ (RRFIXEDSZ+6)
Functions
static bool	dns_process (DNSHandler handler, HostEnt buf, int len)
	Decode the reply from "named".
static DNSEntry *	get_dns (DNSHandler *h, uint16_t id)
	Find a DNSEntry by id.
static void	dns_result (DNSHandler h, DNSEntry e, HostEnt *ent, bool retry)
	We have a result for an entry, return it to the user or retry if it is a retry-able and we have retries left.
static void	write_dns (DNSHandler *h)
	Write up to dns_max_dns_in_flight entries.
static bool	write_dns_event (DNSHandler h, DNSEntry e)
	Construct and Write the request for a single entry (using send(3N)).
static char *	strnchr (char *s, char c, int len)
static uint16_t	ink_get16 (const uint8_t *src)
void	make_ipv4_ptr (in_addr_t addr, char *buffer)
void	make_ipv6_ptr (in6_addr const addr, char buffer)
int	ink_dn_expand (const u_char msg, const u_char eom, const u_char comp_dn, u_char exp_dn, int length)
	Inter-OS portability for dn_expand.
static int	_ink_res_mkquery (ink_res_state res, char qname, int qtype, char buffer)
static unsigned int	get_rcode (char *buff)
static unsigned int	get_rcode (HostEnt *ent)
static bool	good_rcode (char *buff)
static DNSEntry *	get_entry (DNSHandler h, char qname, int qtype)
	Find a DNSEntry by query name and type.
void	ink_dns_init (ModuleVersion v)
Variables
EventType	ET_DNS = ET_CALL
int	dns_timeout = DEFAULT_DNS_TIMEOUT
int	dns_retries = DEFAULT_DNS_RETRIES
int	dns_search = DEFAULT_DNS_SEARCH
int	dns_failover_number = DEFAULT_FAILOVER_NUMBER
int	dns_failover_period = DEFAULT_FAILOVER_PERIOD
int	dns_failover_try_period = DEFAULT_FAILOVER_TRY_PERIOD
int	dns_max_dns_in_flight = MAX_DNS_IN_FLIGHT
int	dns_validate_qname = 0
unsigned int	dns_handler_initialized = 0
int	dns_ns_rr = 0
int	dns_ns_rr_init_down = 1
char *	dns_ns_list = NULL
char *	dns_resolv_conf = NULL
char *	dns_local_ipv6 = NULL
char *	dns_local_ipv4 = NULL
int	dns_thread = 0
int	dns_prefer_ipv6 = 0
DNSProcessor	dnsProcessor
ClassAllocator< DNSEntry >	dnsEntryAllocator ("dnsEntryAllocator")
ClassAllocator< HostEnt >	dnsBufAllocator ("dnsBufAllocator", 2)
static int	try_servers = 0
static int	local_num_entries = 1
static int	attempt_num_entries = 1
char	try_server_names [DEFAULT_NUM_TRY_SERVER][MAXDNAME]
RecRawStatBlock *	dns_rsb

Detailed Description

A brief file description.

License

Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Definition in file DNS.cc.

Define Documentation

#define SRV_COST (RRFIXEDSZ+0)

Definition at line 31 of file DNS.cc.

Referenced by dns_process().

#define SRV_FIXEDSZ (RRFIXEDSZ+6)

Definition at line 35 of file DNS.cc.

#define SRV_PORT (RRFIXEDSZ+4)

Definition at line 33 of file DNS.cc.

Referenced by dns_process().

#define SRV_SERVER (RRFIXEDSZ+6)

Definition at line 34 of file DNS.cc.

Referenced by dns_process().

#define SRV_WEIGHT (RRFIXEDSZ+2)

Definition at line 32 of file DNS.cc.

Referenced by dns_process().

Function Documentation

static int _ink_res_mkquery	(	ink_res_state	res,
		char *	qname,
		int	qtype,
		char *	buffer
	)			`[inline, static]`

Definition at line 540 of file DNS.cc.

References ink_res_mkquery(), and MAX_DNS_PACKET_LEN.

Referenced by DNSHandler::retry_named(), DNSHandler::try_primary_named(), and write_dns_event().

static bool dns_process	(	DNSHandler *	handler,
		HostEnt *	buf,
		int	len
	)			`[static]`

Decode the reply from "named".

Definition at line 1281 of file DNS.cc.

References align_pointer_forward(), attempt_num_entries, HostEnt::buf, countof, Debug, DEFAULT_NUM_TRY_SERVER, DNS_DECREMENT_DYN_STAT, DNS_HOSTBUF_SIZE, dns_in_flight_stat, DNS_INCREMENT_DYN_STAT, dns_lookup_fail_stat, DNS_MAX_ALIASES, dns_response_time_stat, dns_result(), DNS_SUM_DYN_STAT, dns_validate_qname, HostEnt::ent, get_dns(), HostEnt::h_addr_ptrs, HFIXEDSZ, SRV::host, HostEnt::host_aliases, HOST_DB_MAX_ROUND_ROBIN_INFO, SRV::host_len, HostEnt::hostbuf, SRVHosts::hosts, DNSHandler::in_flight, ink_assert, ink_dn_expand(), ink_get16(), ink_get_hrtime(), ink_ns_name_ntop(), ink_strlcpy(), SRV::key, local_num_entries, makeHostHash(), memcpy, Continuation::mutex, NS_GET16, NS_GET32, SRV::port, SRV::priority, DNSEntry::qname, DNSEntry::qname_len, DNSEntry::qtype, DNSEntry::send_time, SRV_COST, SRVHosts::srv_host_count, HostEnt::srv_hosts, SRVHosts::srv_hosts_length, SRV_PORT, SRV_SERVER, SRV_WEIGHT, try_server_names, try_servers, HostEnt::ttl, Warning, SRV::weight, and DNSEntry::written_flag.

Referenced by DNSHandler::recv_dns().

static void dns_result	(	DNSHandler *	h,
		DNSEntry *	e,
		HostEnt *	ent,
		bool	retry
	)			`[static]`

We have a result for an entry, return it to the user or retry if it is a retry-able and we have retries left.

Definition at line 1113 of file DNS.cc.

References DNSEntry::action, BAD_DNS_RESULT, Action::cancel(), Action::cancelled, Debug, dns_fail_time_stat, DNS_INCREMENT_DYN_STAT, dns_lookup_fail_stat, dns_lookup_success_stat, dns_max_retries_exceeded_stat, DNS_PERIOD, dns_retries, dns_retries_stat, dns_success_time_stat, DNS_SUM_DYN_STAT, DNSEntry::domains, HostEnt::ent, DNSHandler::entries, DNSEntry::id, ink_get_hrtime(), ink_strlcpy(), is_debug_tag_set, DNSEntry::last, Action::mutex, Continuation::mutex, MUTEX_TRY_LOCK, DNSEntry::orig_qname_len, DNSEntry::post(), DNSEntry::postEvent(), DNSEntry::qname, DNSEntry::qname_len, DNSEntry::qtype, DNSHandler::release_query_id(), Queue< C, L >::remove(), DNSEntry::result_ent, DNSEntry::retries, EThread::schedule_imm_signal(), SET_CONTINUATION_HANDLER, DNSEntry::submit_thread, DNSEntry::submit_time, DNSEntry::timeout, and write_dns().

Referenced by dns_process(), DNSEntry::mainEvent(), and write_dns_event().

static DNSEntry * get_dns	(	DNSHandler *	h,
		uint16_t	id
	)			`[inline, static]`

Find a DNSEntry by id.

Definition at line 847 of file DNS.cc.

References DNSHandler::entries, and DLL< C, L >::head.

Referenced by dns_process().

static DNSEntry* get_entry	(	DNSHandler *	h,
		char *	qname,
		int	qtype
	)			`[inline, static]`

Find a DNSEntry by query name and type.

Definition at line 866 of file DNS.cc.

References DNSHandler::entries, and DLL< C, L >::head.

Referenced by DNSEntry::mainEvent().

static unsigned int get_rcode ( HostEnt * ent ) [inline, static]

Definition at line 716 of file DNS.cc.

References get_rcode().

static unsigned int get_rcode ( char * buff ) [inline, static]

Definition at line 712 of file DNS.cc.

Referenced by get_rcode(), good_rcode(), and DNSHandler::recv_dns().

static bool good_rcode ( char * buff ) [static]

Definition at line 721 of file DNS.cc.

References get_rcode().

Referenced by DNSHandler::recv_dns().

int ink_dn_expand	(	const u_char *	msg,
		const u_char *	eom,
		const u_char *	comp_dn,
		u_char *	exp_dn,
		int	length
	)			`[inline]`

Inter-OS portability for dn_expand.

dn_expand() expands the compressed domain name comp_dn to a full domain name. Expanded names are converted to upper case. msg is a pointer to the beginning of the message, exp_dn is a pointer to a buffer of size length for the result. The size of compressed name is returned or -1 if there was an error.

Definition at line 336 of file DNS.cc.

Referenced by dns_process().

void ink_dns_init ( ModuleVersion v )

Definition at line 1605 of file DNS.cc.

References checkModuleVersion(), Debug, dns_fail_time_stat, dns_in_flight_stat, dns_lookup_fail_stat, dns_lookup_success_stat, dns_max_retries_exceeded_stat, dns_response_time_stat, dns_retries_stat, DNS_Stat_Count, dns_success_time_stat, dns_total_lookups_stat, HOSTDB_MODULE_VERSION, ink_release_assert, RecAllocateRawStatBlock(), RECD_INT, RECP_NON_PERSISTENT, RECP_PERSISTENT, RecRawStatSyncHrTimeAvg(), RecRawStatSyncSum(), RecRegisterRawStat, and RECT_PROCESS.