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Diffstat (limited to 'src/c-ares/ares_private.h')
-rw-r--r-- | src/c-ares/ares_private.h | 368 |
1 files changed, 368 insertions, 0 deletions
diff --git a/src/c-ares/ares_private.h b/src/c-ares/ares_private.h new file mode 100644 index 00000000..7359d5eb --- /dev/null +++ b/src/c-ares/ares_private.h @@ -0,0 +1,368 @@ +#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 <netinet/in.h> +#endif + +#ifdef WATT32 +#include <tcp.h> +#include <sys/ioctl.h> +#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 + +#ifdef CARES_EXPOSE_STATICS +/* Make some internal functions visible for testing */ +#define STATIC_TESTABLE +#else +#define STATIC_TESTABLE static +#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 + +#include "ares_strdup.h" + +#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; + 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 { + 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; /* 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: */ +#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; + + ares_sock_config_callback sock_config_cb; + void *sock_config_cb_data; + + const struct ares_socket_functions * sock_funcs; + void *sock_func_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); +#endif + +void ares__socket_close(ares_channel, ares_socket_t); + +#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. */ +#define HEADER_CURL_SETUP_ONCE_H +#include "../lib/memdebug.h" +#endif + +#endif /* __ARES_PRIVATE_H */ |