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#ifndef __ARES_PRIVATE_H
#define __ARES_PRIVATE_H
/* Copyright 1998 by the Massachusetts Institute of Technology.
* Copyright (C) 2004-2010 by Daniel Stenberg
* Permission to use, copy, modify, and distribute this
* software and its documentation for any purpose and without
* fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright
* notice and this permission notice appear in supporting
* documentation, and that the name of M.I.T. not be used in
* advertising or publicity pertaining to distribution of the
* software without specific, written prior permission.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is"
* without express or implied warranty.
* Define WIN32 when build target is Win32 API
#if (defined(_WIN32) || defined(__WIN32__)) && !defined(WIN32)
#define WIN32
#include <netinet/in.h>
#ifdef WATT32
#include <tcp.h>
#include <sys/ioctl.h>
#define writev(s,v,c) writev_s(s,v,c)
#define HAVE_WRITEV 1
#define DEFAULT_TIMEOUT 5000 /* milliseconds */
#define INADDR_NONE 0xffffffff
/* Make some internal functions visible for testing */
#define STATIC_TESTABLE static
#if defined(WIN32) && !defined(WATT32)
#define WIN_NS_9X "System\\CurrentControlSet\\Services\\VxD\\MSTCP"
#define WIN_NS_NT_KEY "System\\CurrentControlSet\\Services\\Tcpip\\Parameters"
#define NAMESERVER "NameServer"
#define DHCPNAMESERVER "DhcpNameServer"
#define DATABASEPATH "DatabasePath"
#define WIN_PATH_HOSTS "\\hosts"
#elif defined(WATT32)
#define PATH_RESOLV_CONF "/dev/ENV/etc/resolv.conf"
#elif defined(NETWARE)
#define PATH_RESOLV_CONF "sys:/etc/resolv.cfg"
#define PATH_HOSTS "sys:/etc/hosts"
#elif defined(__riscos__)
#define PATH_HOSTS "InetDBase:Hosts"
#define PATH_RESOLV_CONF "/etc/resolv.conf"
#ifdef ETC_INET
#define PATH_HOSTS "/etc/inet/hosts"
#define PATH_HOSTS "/etc/hosts"
#define ARES_ID_KEY_LEN 31
#include "ares_ipv6.h"
#include "ares_llist.h"
# include "ares_getenv.h"
# define getenv(ptr) ares_getenv(ptr)
#include "ares_strdup.h"
# include "ares_strcasecmp.h"
# define strcasecmp(p1,p2) ares_strcasecmp(p1,p2)
# include "ares_strcasecmp.h"
# define strncasecmp(p1,p2,n) ares_strncasecmp(p1,p2,n)
# include "ares_writev.h"
# define writev(s,ptr,cnt) ares_writev(s,ptr,cnt)
/********* EDNS defines section ******/
#define EDNSPACKETSZ 1280 /* Reasonable UDP payload size, as suggested
in RFC2671 */
#define MAXENDSSZ 4096 /* Maximum (local) limit for edns packet size */
#define EDNSFIXEDSZ 11 /* Size of EDNS header */
/********* EDNS defines section ******/
struct ares_addr {
int family;
union {
struct in_addr addr4;
struct ares_in6_addr addr6;
} addr;
int udp_port; /* stored in network order */
int tcp_port; /* stored in network order */
#define addrV4 addr.addr4
#define addrV6 addr.addr6
struct query;
struct send_request {
/* Remaining data to send */
const unsigned char *data;
size_t len;
/* The query for which we're sending this data */
struct query* owner_query;
/* The buffer we're using, if we have our own copy of the packet */
unsigned char *data_storage;
/* Next request in queue */
struct send_request *next;
struct server_state {
struct ares_addr addr;
ares_socket_t udp_socket;
ares_socket_t tcp_socket;
/* Mini-buffer for reading the length word */
unsigned char tcp_lenbuf[2];
int tcp_lenbuf_pos;
int tcp_length;
/* Buffer for reading actual TCP data */
unsigned char *tcp_buffer;
int tcp_buffer_pos;
/* TCP output queue */
struct send_request *qhead;
struct send_request *qtail;
/* Which incarnation of this connection is this? We don't want to
* retransmit requests into the very same socket, but if the server
* closes on us and we re-open the connection, then we do want to
* re-send. */
int tcp_connection_generation;
/* Circular, doubly-linked list of outstanding queries to this server */
struct list_node queries_to_server;
/* Link back to owning channel */
ares_channel channel;
/* Is this server broken? We mark connections as broken when a
* request that is queued for sending times out.
int is_broken;
/* State to represent a DNS query */
struct query {
/* Query ID from qbuf, for faster lookup, and current timeout */
unsigned short qid;
struct timeval timeout;
* Links for the doubly-linked lists in which we insert a query.
* These circular, doubly-linked lists that are hash-bucketed based
* the attributes we care about, help making most important
* operations O(1).
struct list_node queries_by_qid; /* hopefully in same cache line as qid */
struct list_node queries_by_timeout;
struct list_node queries_to_server;
struct list_node all_queries;
/* Query buf with length at beginning, for TCP transmission */
unsigned char *tcpbuf;
int tcplen;
/* Arguments passed to ares_send() (qbuf points into tcpbuf) */
const unsigned char *qbuf;
int qlen;
ares_callback callback;
void *arg;
/* Query status */
int try_count; /* Number of times we tried this query already. */
int server; /* Server this query has last been sent to. */
struct query_server_info *server_info; /* per-server state */
int using_tcp;
int error_status;
int timeouts; /* number of timeouts we saw for this request */
/* Per-server state for a query */
struct query_server_info {
int skip_server; /* should we skip server, due to errors, etc? */
int tcp_connection_generation; /* into which TCP connection did we send? */
/* An IP address pattern; matches an IP address X if X & mask == addr */
#define PATTERN_MASK 0x1
#define PATTERN_CIDR 0x2
struct apattern {
struct in_addr addr4;
struct ares_in6_addr addr6;
} addr;
struct in_addr addr4;
struct ares_in6_addr addr6;
unsigned short bits;
} mask;
int family;
unsigned short type;
typedef struct rc4_key
unsigned char state[256];
unsigned char x;
unsigned char y;
} rc4_key;
struct ares_channeldata {
/* Configuration data */
int flags;
int timeout; /* in milliseconds */
int tries;
int ndots;
int rotate; /* if true, all servers specified are used */
int udp_port; /* stored in network order */
int tcp_port; /* stored in network order */
int socket_send_buffer_size;
int socket_receive_buffer_size;
char **domains;
int ndomains;
struct apattern *sortlist;
int nsort;
char *lookups;
int ednspsz;
/* For binding to local devices and/or IP addresses. Leave
* them null/zero for no binding.
char local_dev_name[32];
unsigned int local_ip4;
unsigned char local_ip6[16];
int optmask; /* the option bitfield passed in at init time */
/* Server addresses and communications state */
struct server_state *servers;
int nservers;
/* ID to use for next query */
unsigned short next_id;
/* key to use when generating new ids */
rc4_key id_key;
/* Generation number to use for the next TCP socket open/close */
int tcp_connection_generation;
/* The time at which we last called process_timeouts(). Uses integer seconds
just to draw the line somewhere. */
time_t last_timeout_processed;
/* Last server we sent a query to. */
int last_server;
/* Circular, doubly-linked list of queries, bucketed various ways.... */
/* All active queries in a single list: */
struct list_node all_queries;
/* Queries bucketed by qid, for quickly dispatching DNS responses: */
#define ARES_QID_TABLE_SIZE 2048
struct list_node queries_by_qid[ARES_QID_TABLE_SIZE];
/* Queries bucketed by timeout, for quickly handling timeouts: */
struct list_node queries_by_timeout[ARES_TIMEOUT_TABLE_SIZE];
ares_sock_state_cb sock_state_cb;
void *sock_state_cb_data;
ares_sock_create_callback sock_create_cb;
void *sock_create_cb_data;
/* Memory management functions */
extern void *(*ares_malloc)(size_t size);
extern void *(*ares_realloc)(void *ptr, size_t size);
extern void (*ares_free)(void *ptr);
/* return true if now is exactly check time or later */
int ares__timedout(struct timeval *now,
struct timeval *check);
void ares__send_query(ares_channel channel, struct query *query,
struct timeval *now);
void ares__close_sockets(ares_channel channel, struct server_state *server);
int ares__get_hostent(FILE *fp, int family, struct hostent **host);
int ares__read_line(FILE *fp, char **buf, size_t *bufsize);
void ares__free_query(struct query *query);
unsigned short ares__generate_new_id(rc4_key* key);
struct timeval ares__tvnow(void);
int ares__expand_name_for_response(const unsigned char *encoded,
const unsigned char *abuf, int alen,
char **s, long *enclen);
void ares__init_servers_state(ares_channel channel);
void ares__destroy_servers_state(ares_channel channel);
#if 0 /* Not used */
long ares__tvdiff(struct timeval t1, struct timeval t2);
#define ARES_SWAP_BYTE(a,b) \
{ unsigned char swapByte = *(a); *(a) = *(b); *(b) = swapByte; }
#define SOCK_STATE_CALLBACK(c, s, r, w) \
do { \
if ((c)->sock_state_cb) \
(c)->sock_state_cb((c)->sock_state_cb_data, (s), (r), (w)); \
/* This is low-level hard-hacking memory leak tracking and similar. Using the
libcurl lowlevel code from within library is ugly and only works when
c-ares is built and linked with a similarly curldebug-enabled libcurl,
but we do this anyway for convenience. */
#include "../lib/memdebug.h"
#endif /* __ARES_PRIVATE_H */
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