#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 #endif #ifdef HAVE_NETINET_IN_H #include #endif #ifdef WATT32 #include #include #define writev(s,v,c) writev_s(s,v,c) #define HAVE_WRITEV 1 #endif #define DEFAULT_TIMEOUT 5000 /* milliseconds */ #define DEFAULT_TRIES 4 #ifndef INADDR_NONE #define INADDR_NONE 0xffffffff #endif #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" #else #define PATH_RESOLV_CONF "/etc/resolv.conf" #ifdef ETC_INET #define PATH_HOSTS "/etc/inet/hosts" #else #define PATH_HOSTS "/etc/hosts" #endif #endif #define ARES_ID_KEY_LEN 31 #include "ares_ipv6.h" #include "ares_llist.h" #ifndef HAVE_GETENV # include "ares_getenv.h" # define getenv(ptr) ares_getenv(ptr) #endif #ifndef HAVE_STRDUP # include "ares_strdup.h" # define strdup(ptr) ares_strdup(ptr) #endif #ifndef HAVE_STRCASECMP # include "ares_strcasecmp.h" # define strcasecmp(p1,p2) ares_strcasecmp(p1,p2) #endif #ifndef HAVE_STRNCASECMP # include "ares_strcasecmp.h" # define strncasecmp(p1,p2,n) ares_strncasecmp(p1,p2,n) #endif #ifndef HAVE_WRITEV # include "ares_writev.h" # define writev(s,ptr,cnt) ares_writev(s,ptr,cnt) #endif /********* 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; }; #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 { union { struct in_addr addr4; struct ares_in6_addr addr6; } addr; union { 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; int tcp_port; 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: */ #define ARES_TIMEOUT_TABLE_SIZE 1024 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; }; /* return true if now is exactly check time or later */ int ares__timedout(struct timeval *now, struct timeval *check); /* add the specific number of milliseconds to the time in the first argument */ int ares__timeadd(struct timeval *now, int millisecs); /* return time offset between now and (future) check, in milliseconds */ long ares__timeoffset(struct timeval *now, struct timeval *check); /* returns ARES_SUCCESS if library has been initialized */ int ares_library_initialized(void); void ares__rc4(rc4_key* key,unsigned char *buffer_ptr, int buffer_len); 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); #endif #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)); \ } WHILE_FALSE #ifdef CURLDEBUG /* 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 #endif /* __ARES_PRIVATE_H */