Gilad Arnold | 968bf19 | 2015-07-17 00:23:30 -0700 | [diff] [blame] | 1 | #ifndef __ARES_PRIVATE_H |
| 2 | #define __ARES_PRIVATE_H |
| 3 | |
| 4 | |
| 5 | /* Copyright 1998 by the Massachusetts Institute of Technology. |
| 6 | * Copyright (C) 2004-2010 by Daniel Stenberg |
| 7 | * |
| 8 | * Permission to use, copy, modify, and distribute this |
| 9 | * software and its documentation for any purpose and without |
| 10 | * fee is hereby granted, provided that the above copyright |
| 11 | * notice appear in all copies and that both that copyright |
| 12 | * notice and this permission notice appear in supporting |
| 13 | * documentation, and that the name of M.I.T. not be used in |
| 14 | * advertising or publicity pertaining to distribution of the |
| 15 | * software without specific, written prior permission. |
| 16 | * M.I.T. makes no representations about the suitability of |
| 17 | * this software for any purpose. It is provided "as is" |
| 18 | * without express or implied warranty. |
| 19 | */ |
| 20 | |
| 21 | /* |
| 22 | * Define WIN32 when build target is Win32 API |
| 23 | */ |
| 24 | |
| 25 | #if (defined(_WIN32) || defined(__WIN32__)) && !defined(WIN32) |
| 26 | #define WIN32 |
| 27 | #endif |
| 28 | |
| 29 | #include <stdio.h> |
| 30 | #include <sys/types.h> |
| 31 | |
| 32 | #ifdef HAVE_NETINET_IN_H |
| 33 | #include <netinet/in.h> |
| 34 | #endif |
| 35 | |
| 36 | #ifdef WATT32 |
| 37 | #include <tcp.h> |
| 38 | #include <sys/ioctl.h> |
| 39 | #define writev(s,v,c) writev_s(s,v,c) |
| 40 | #define HAVE_WRITEV 1 |
| 41 | #endif |
| 42 | |
| 43 | #ifdef NETWARE |
| 44 | #include <time.h> |
| 45 | #endif |
| 46 | |
| 47 | #define DEFAULT_TIMEOUT 5000 /* milliseconds */ |
| 48 | #define DEFAULT_TRIES 4 |
| 49 | #ifndef INADDR_NONE |
| 50 | #define INADDR_NONE 0xffffffff |
| 51 | #endif |
| 52 | |
| 53 | #if defined(WIN32) && !defined(WATT32) |
| 54 | |
| 55 | #define WIN_NS_9X "System\\CurrentControlSet\\Services\\VxD\\MSTCP" |
| 56 | #define WIN_NS_NT_KEY "System\\CurrentControlSet\\Services\\Tcpip\\Parameters" |
| 57 | #define NAMESERVER "NameServer" |
| 58 | #define DHCPNAMESERVER "DhcpNameServer" |
| 59 | #define DATABASEPATH "DatabasePath" |
| 60 | #define WIN_PATH_HOSTS "\\hosts" |
| 61 | |
| 62 | #elif defined(WATT32) |
| 63 | |
| 64 | #define PATH_RESOLV_CONF "/dev/ENV/etc/resolv.conf" |
| 65 | |
| 66 | #elif defined(NETWARE) |
| 67 | |
| 68 | #define PATH_RESOLV_CONF "sys:/etc/resolv.cfg" |
| 69 | #define PATH_HOSTS "sys:/etc/hosts" |
| 70 | |
| 71 | #elif defined(__riscos__) |
| 72 | |
| 73 | #define PATH_HOSTS "InetDBase:Hosts" |
| 74 | |
| 75 | #else |
| 76 | |
| 77 | #define PATH_RESOLV_CONF "/etc/resolv.conf" |
| 78 | #ifdef ETC_INET |
| 79 | #define PATH_HOSTS "/etc/inet/hosts" |
| 80 | #else |
| 81 | #define PATH_HOSTS "/etc/hosts" |
| 82 | #endif |
| 83 | |
| 84 | #endif |
| 85 | |
| 86 | #define ARES_ID_KEY_LEN 31 |
| 87 | |
| 88 | #include "ares_ipv6.h" |
| 89 | #include "ares_llist.h" |
| 90 | |
| 91 | #ifndef HAVE_GETENV |
| 92 | # include "ares_getenv.h" |
| 93 | # define getenv(ptr) ares_getenv(ptr) |
| 94 | #endif |
| 95 | |
| 96 | #ifndef HAVE_STRDUP |
| 97 | # include "ares_strdup.h" |
| 98 | # define strdup(ptr) ares_strdup(ptr) |
| 99 | #endif |
| 100 | |
| 101 | #ifndef HAVE_STRCASECMP |
| 102 | # include "ares_strcasecmp.h" |
| 103 | # define strcasecmp(p1,p2) ares_strcasecmp(p1,p2) |
| 104 | #endif |
| 105 | |
| 106 | #ifndef HAVE_STRNCASECMP |
| 107 | # include "ares_strcasecmp.h" |
| 108 | # define strncasecmp(p1,p2,n) ares_strncasecmp(p1,p2,n) |
| 109 | #endif |
| 110 | |
| 111 | #ifndef HAVE_WRITEV |
| 112 | # include "ares_writev.h" |
| 113 | # define writev(s,ptr,cnt) ares_writev(s,ptr,cnt) |
| 114 | #endif |
| 115 | |
| 116 | struct ares_addr { |
| 117 | int family; |
| 118 | union { |
| 119 | struct in_addr addr4; |
| 120 | struct ares_in6_addr addr6; |
| 121 | } addr; |
| 122 | }; |
| 123 | #define addrV4 addr.addr4 |
| 124 | #define addrV6 addr.addr6 |
| 125 | |
| 126 | struct query; |
| 127 | |
| 128 | struct send_request { |
| 129 | /* Remaining data to send */ |
| 130 | const unsigned char *data; |
| 131 | size_t len; |
| 132 | |
| 133 | /* The query for which we're sending this data */ |
| 134 | struct query* owner_query; |
| 135 | /* The buffer we're using, if we have our own copy of the packet */ |
| 136 | unsigned char *data_storage; |
| 137 | |
| 138 | /* Next request in queue */ |
| 139 | struct send_request *next; |
| 140 | }; |
| 141 | |
| 142 | struct server_state { |
| 143 | struct ares_addr addr; |
| 144 | ares_socket_t udp_socket; |
| 145 | ares_socket_t tcp_socket; |
| 146 | |
| 147 | /* Mini-buffer for reading the length word */ |
| 148 | unsigned char tcp_lenbuf[2]; |
| 149 | int tcp_lenbuf_pos; |
| 150 | int tcp_length; |
| 151 | |
| 152 | /* Buffer for reading actual TCP data */ |
| 153 | unsigned char *tcp_buffer; |
| 154 | int tcp_buffer_pos; |
| 155 | |
| 156 | /* TCP output queue */ |
| 157 | struct send_request *qhead; |
| 158 | struct send_request *qtail; |
| 159 | |
| 160 | /* Which incarnation of this connection is this? We don't want to |
| 161 | * retransmit requests into the very same socket, but if the server |
| 162 | * closes on us and we re-open the connection, then we do want to |
| 163 | * re-send. */ |
| 164 | int tcp_connection_generation; |
| 165 | |
| 166 | /* Circular, doubly-linked list of outstanding queries to this server */ |
| 167 | struct list_node queries_to_server; |
| 168 | |
| 169 | /* Link back to owning channel */ |
| 170 | ares_channel channel; |
| 171 | |
| 172 | /* Is this server broken? We mark connections as broken when a |
| 173 | * request that is queued for sending times out. |
| 174 | */ |
| 175 | int is_broken; |
| 176 | }; |
| 177 | |
| 178 | /* State to represent a DNS query */ |
| 179 | struct query { |
| 180 | /* Query ID from qbuf, for faster lookup, and current timeout */ |
| 181 | unsigned short qid; |
| 182 | struct timeval timeout; |
| 183 | |
| 184 | /* |
| 185 | * Links for the doubly-linked lists in which we insert a query. |
| 186 | * These circular, doubly-linked lists that are hash-bucketed based |
| 187 | * the attributes we care about, help making most important |
| 188 | * operations O(1). |
| 189 | */ |
| 190 | struct list_node queries_by_qid; /* hopefully in same cache line as qid */ |
| 191 | struct list_node queries_by_timeout; |
| 192 | struct list_node queries_to_server; |
| 193 | struct list_node all_queries; |
| 194 | |
| 195 | /* Query buf with length at beginning, for TCP transmission */ |
| 196 | unsigned char *tcpbuf; |
| 197 | int tcplen; |
| 198 | |
| 199 | /* Arguments passed to ares_send() (qbuf points into tcpbuf) */ |
| 200 | const unsigned char *qbuf; |
| 201 | int qlen; |
| 202 | ares_callback callback; |
| 203 | void *arg; |
| 204 | |
| 205 | /* Query status */ |
| 206 | int try_count; /* Number of times we tried this query already. */ |
| 207 | int server; /* Server this query has last been sent to. */ |
| 208 | struct query_server_info *server_info; /* per-server state */ |
| 209 | int using_tcp; |
| 210 | int error_status; |
| 211 | int timeouts; /* number of timeouts we saw for this request */ |
| 212 | }; |
| 213 | |
| 214 | /* Per-server state for a query */ |
| 215 | struct query_server_info { |
| 216 | int skip_server; /* should we skip server, due to errors, etc? */ |
| 217 | int tcp_connection_generation; /* into which TCP connection did we send? */ |
| 218 | }; |
| 219 | |
| 220 | /* An IP address pattern; matches an IP address X if X & mask == addr */ |
| 221 | #define PATTERN_MASK 0x1 |
| 222 | #define PATTERN_CIDR 0x2 |
| 223 | |
| 224 | struct apattern { |
| 225 | union |
| 226 | { |
| 227 | struct in_addr addr4; |
| 228 | struct ares_in6_addr addr6; |
| 229 | } addr; |
| 230 | union |
| 231 | { |
| 232 | struct in_addr addr4; |
| 233 | struct ares_in6_addr addr6; |
| 234 | unsigned short bits; |
| 235 | } mask; |
| 236 | int family; |
| 237 | unsigned short type; |
| 238 | }; |
| 239 | |
| 240 | typedef struct rc4_key |
| 241 | { |
| 242 | unsigned char state[256]; |
| 243 | unsigned char x; |
| 244 | unsigned char y; |
| 245 | } rc4_key; |
| 246 | |
| 247 | struct ares_channeldata { |
| 248 | /* Configuration data */ |
| 249 | int flags; |
| 250 | int timeout; /* in milliseconds */ |
| 251 | int tries; |
| 252 | int ndots; |
| 253 | int rotate; /* if true, all servers specified are used */ |
| 254 | int udp_port; |
| 255 | int tcp_port; |
| 256 | int socket_send_buffer_size; |
| 257 | int socket_receive_buffer_size; |
| 258 | char **domains; |
| 259 | int ndomains; |
| 260 | struct apattern *sortlist; |
| 261 | int nsort; |
| 262 | char *lookups; |
| 263 | |
| 264 | /* For binding to local devices and/or IP addresses. Leave |
| 265 | * them null/zero for no binding. |
| 266 | */ |
| 267 | char local_dev_name[32]; |
| 268 | unsigned int local_ip4; |
| 269 | unsigned char local_ip6[16]; |
| 270 | |
| 271 | int optmask; /* the option bitfield passed in at init time */ |
| 272 | |
| 273 | /* Server addresses and communications state */ |
| 274 | struct server_state *servers; |
| 275 | int nservers; |
| 276 | |
| 277 | /* ID to use for next query */ |
| 278 | unsigned short next_id; |
| 279 | /* key to use when generating new ids */ |
| 280 | rc4_key id_key; |
| 281 | |
| 282 | /* Generation number to use for the next TCP socket open/close */ |
| 283 | int tcp_connection_generation; |
| 284 | |
| 285 | /* The time at which we last called process_timeouts(). Uses integer seconds |
| 286 | just to draw the line somewhere. */ |
| 287 | time_t last_timeout_processed; |
| 288 | |
| 289 | /* Last server we sent a query to. */ |
| 290 | int last_server; |
| 291 | |
| 292 | /* Circular, doubly-linked list of queries, bucketed various ways.... */ |
| 293 | /* All active queries in a single list: */ |
| 294 | struct list_node all_queries; |
| 295 | /* Queries bucketed by qid, for quickly dispatching DNS responses: */ |
| 296 | #define ARES_QID_TABLE_SIZE 2048 |
| 297 | struct list_node queries_by_qid[ARES_QID_TABLE_SIZE]; |
| 298 | /* Queries bucketed by timeout, for quickly handling timeouts: */ |
| 299 | #define ARES_TIMEOUT_TABLE_SIZE 1024 |
| 300 | struct list_node queries_by_timeout[ARES_TIMEOUT_TABLE_SIZE]; |
| 301 | |
| 302 | ares_sock_state_cb sock_state_cb; |
| 303 | void *sock_state_cb_data; |
| 304 | |
| 305 | ares_sock_create_callback sock_create_cb; |
| 306 | void *sock_create_cb_data; |
| 307 | }; |
| 308 | |
| 309 | /* return true if now is exactly check time or later */ |
| 310 | int ares__timedout(struct timeval *now, |
| 311 | struct timeval *check); |
| 312 | /* add the specific number of milliseconds to the time in the first argument */ |
| 313 | int ares__timeadd(struct timeval *now, |
| 314 | int millisecs); |
| 315 | /* return time offset between now and (future) check, in milliseconds */ |
| 316 | long ares__timeoffset(struct timeval *now, |
| 317 | struct timeval *check); |
| 318 | /* returns ARES_SUCCESS if library has been initialized */ |
| 319 | int ares_library_initialized(void); |
| 320 | void ares__rc4(rc4_key* key,unsigned char *buffer_ptr, int buffer_len); |
| 321 | void ares__send_query(ares_channel channel, struct query *query, |
| 322 | struct timeval *now); |
| 323 | void ares__close_sockets(ares_channel channel, struct server_state *server); |
| 324 | int ares__get_hostent(FILE *fp, int family, struct hostent **host); |
| 325 | int ares__read_line(FILE *fp, char **buf, size_t *bufsize); |
| 326 | void ares__free_query(struct query *query); |
| 327 | unsigned short ares__generate_new_id(rc4_key* key); |
| 328 | struct timeval ares__tvnow(void); |
| 329 | int ares__expand_name_for_response(const unsigned char *encoded, |
| 330 | const unsigned char *abuf, int alen, |
| 331 | char **s, long *enclen); |
| 332 | void ares__init_servers_state(ares_channel channel); |
| 333 | void ares__destroy_servers_state(ares_channel channel); |
| 334 | #if 0 /* Not used */ |
| 335 | long ares__tvdiff(struct timeval t1, struct timeval t2); |
| 336 | #endif |
| 337 | |
| 338 | #define ARES_SWAP_BYTE(a,b) \ |
| 339 | { unsigned char swapByte = *(a); *(a) = *(b); *(b) = swapByte; } |
| 340 | |
| 341 | #define SOCK_STATE_CALLBACK(c, s, r, w) \ |
| 342 | do { \ |
| 343 | if ((c)->sock_state_cb) \ |
| 344 | (c)->sock_state_cb((c)->sock_state_cb_data, (s), (r), (w)); \ |
| 345 | } while (0) |
| 346 | |
| 347 | #ifdef CURLDEBUG |
| 348 | /* This is low-level hard-hacking memory leak tracking and similar. Using the |
| 349 | libcurl lowlevel code from within library is ugly and only works when |
| 350 | c-ares is built and linked with a similarly curldebug-enabled libcurl, |
| 351 | but we do this anyway for convenience. */ |
| 352 | #include "../lib/memdebug.h" |
| 353 | #endif |
| 354 | |
| 355 | #endif /* __ARES_PRIVATE_H */ |