| 1 |
/* Copyright 1998 by the Massachusetts Institute of Technology. |
| 2 |
* |
| 3 |
* Permission to use, copy, modify, and distribute this |
| 4 |
* software and its documentation for any purpose and without |
| 5 |
* fee is hereby granted, provided that the above copyright |
| 6 |
* notice appear in all copies and that both that copyright |
| 7 |
* notice and this permission notice appear in supporting |
| 8 |
* documentation, and that the name of M.I.T. not be used in |
| 9 |
* advertising or publicity pertaining to distribution of the |
| 10 |
* software without specific, written prior permission. |
| 11 |
* M.I.T. makes no representations about the suitability of |
| 12 |
* this software for any purpose. It is provided "as is" |
| 13 |
* without express or implied warranty. |
| 14 |
*/ |
| 15 |
|
| 16 |
|
| 17 |
#include <sys/types.h> |
| 18 |
#include <stdio.h> |
| 19 |
#include <stdlib.h> |
| 20 |
#include <string.h> |
| 21 |
#include <ctype.h> |
| 22 |
#include <time.h> |
| 23 |
#include <assert.h> |
| 24 |
|
| 25 |
#ifndef WIN32 |
| 26 |
#include <sys/time.h> |
| 27 |
#include <sys/param.h> |
| 28 |
#include <netinet/in.h> |
| 29 |
#include <arpa/inet.h> |
| 30 |
#ifndef __CYGWIN__ |
| 31 |
# include <arpa/nameser.h> |
| 32 |
#endif |
| 33 |
#include <unistd.h> |
| 34 |
#include <errno.h> |
| 35 |
#include <netdb.h> |
| 36 |
#else |
| 37 |
#include <Winsock2.h> |
| 38 |
#include <io.h> |
| 39 |
#include <Windns.h> |
| 40 |
#endif |
| 41 |
|
| 42 |
#include "ares.h" |
| 43 |
#include "ares_private.h" |
| 44 |
|
| 45 |
static int init_by_options(ares_channel channel, struct ares_options *options, |
| 46 |
int optmask); |
| 47 |
static int init_by_environment(ares_channel channel); |
| 48 |
static int init_by_resolv_conf(ares_channel channel); |
| 49 |
static int init_by_defaults(ares_channel channel); |
| 50 |
static int config_domain(ares_channel channel, char *str); |
| 51 |
static int config_lookup(ares_channel channel, const char *str); |
| 52 |
static int config_nameserver(struct server_state **servers, int *nservers, |
| 53 |
const char *str); |
| 54 |
static int config_sortlist(struct apattern **sortlist, int *nsort, |
| 55 |
const char *str); |
| 56 |
static int set_search(ares_channel channel, const char *str); |
| 57 |
static int set_options(ares_channel channel, const char *str); |
| 58 |
static char *try_config(char *s, char *opt); |
| 59 |
static const char *try_option(const char *p, const char *q, const char *opt); |
| 60 |
static int ip_addr(const char *s, int len, struct in_addr *addr); |
| 61 |
static void natural_mask(struct apattern *pat); |
| 62 |
|
| 63 |
int ares_init(ares_channel *channelptr) |
| 64 |
{ |
| 65 |
return ares_init_options(channelptr, NULL, 0); |
| 66 |
} |
| 67 |
|
| 68 |
int ares_init_options(ares_channel *channelptr, struct ares_options *options, |
| 69 |
int optmask) |
| 70 |
{ |
| 71 |
ares_channel channel; |
| 72 |
int i, status; |
| 73 |
struct server_state *server; |
| 74 |
// struct timeval tv; |
| 75 |
|
| 76 |
channel = malloc(sizeof(struct ares_channeldata)); |
| 77 |
if (!channel) |
| 78 |
return ARES_ENOMEM; |
| 79 |
|
| 80 |
/* Set everything to distinguished values so we know they haven't |
| 81 |
* been set yet. |
| 82 |
*/ |
| 83 |
channel->flags = -1; |
| 84 |
channel->timeout = -1; |
| 85 |
channel->tries = -1; |
| 86 |
channel->ndots = -1; |
| 87 |
channel->udp_port = -1; |
| 88 |
channel->tcp_port = -1; |
| 89 |
channel->nservers = -1; |
| 90 |
channel->ndomains = -1; |
| 91 |
channel->nsort = -1; |
| 92 |
channel->lookups = NULL; |
| 93 |
|
| 94 |
/* Initialize configuration by each of the four sources, from highest |
| 95 |
* precedence to lowest. |
| 96 |
*/ |
| 97 |
status = init_by_options(channel, options, optmask); |
| 98 |
if (status == ARES_SUCCESS) |
| 99 |
status = init_by_environment(channel); |
| 100 |
if (status == ARES_SUCCESS) |
| 101 |
status = init_by_resolv_conf(channel); |
| 102 |
if (status == ARES_SUCCESS) |
| 103 |
status = init_by_defaults(channel); |
| 104 |
if (status != ARES_SUCCESS) |
| 105 |
{ |
| 106 |
/* Something failed; clean up memory we may have allocated. */ |
| 107 |
if (channel->nservers != -1) |
| 108 |
free(channel->servers); |
| 109 |
if (channel->ndomains != -1) |
| 110 |
{ |
| 111 |
for (i = 0; i < channel->ndomains; i++) |
| 112 |
free(channel->domains[i]); |
| 113 |
free(channel->domains); |
| 114 |
} |
| 115 |
if (channel->nsort != -1) |
| 116 |
free(channel->sortlist); |
| 117 |
free(channel->lookups); |
| 118 |
free(channel); |
| 119 |
return status; |
| 120 |
} |
| 121 |
|
| 122 |
/* Trim to one server if ARES_FLAG_PRIMARY is set. */ |
| 123 |
if ((channel->flags & ARES_FLAG_PRIMARY) && channel->nservers > 1) |
| 124 |
channel->nservers = 1; |
| 125 |
|
| 126 |
/* Initialize server states. */ |
| 127 |
for (i = 0; i < channel->nservers; i++) |
| 128 |
{ |
| 129 |
server = &channel->servers[i]; |
| 130 |
server->udp_socket = -1; |
| 131 |
server->tcp_socket = -1; |
| 132 |
server->tcp_lenbuf_pos = 0; |
| 133 |
server->tcp_buffer = NULL; |
| 134 |
server->qhead = NULL; |
| 135 |
server->qtail = NULL; |
| 136 |
} |
| 137 |
|
| 138 |
/* Choose a somewhat random query ID. The main point is to avoid |
| 139 |
* collisions with stale queries. An attacker trying to spoof a DNS |
| 140 |
* answer also has to guess the query ID, but it's only a 16-bit |
| 141 |
* field, so there's not much to be done about that. |
| 142 |
*/ |
| 143 |
// gettimeofday(&tv, NULL); |
| 144 |
// channel->next_id = (tv.tv_sec ^ tv.tv_usec ^ getpid()) & 0xffff; |
| 145 |
{ |
| 146 |
static int cjNextID=1; |
| 147 |
channel->next_id = cjNextID++; |
| 148 |
} |
| 149 |
|
| 150 |
channel->queries = NULL; |
| 151 |
|
| 152 |
*channelptr = channel; |
| 153 |
return ARES_SUCCESS; |
| 154 |
} |
| 155 |
|
| 156 |
static int init_by_options(ares_channel channel, struct ares_options *options, |
| 157 |
int optmask) |
| 158 |
{ |
| 159 |
int i; |
| 160 |
|
| 161 |
/* Easy stuff. */ |
| 162 |
if ((optmask & ARES_OPT_FLAGS) && channel->flags == -1) |
| 163 |
channel->flags = options->flags; |
| 164 |
if ((optmask & ARES_OPT_TIMEOUT) && channel->timeout == -1) |
| 165 |
channel->timeout = options->timeout; |
| 166 |
if ((optmask & ARES_OPT_TRIES) && channel->tries == -1) |
| 167 |
channel->tries = options->tries; |
| 168 |
if ((optmask & ARES_OPT_NDOTS) && channel->ndots == -1) |
| 169 |
channel->ndots = options->ndots; |
| 170 |
if ((optmask & ARES_OPT_UDP_PORT) && channel->udp_port == -1) |
| 171 |
channel->udp_port = options->udp_port; |
| 172 |
if ((optmask & ARES_OPT_TCP_PORT) && channel->tcp_port == -1) |
| 173 |
channel->tcp_port = options->tcp_port; |
| 174 |
|
| 175 |
/* Copy the servers, if given. */ |
| 176 |
if ((optmask & ARES_OPT_SERVERS) && channel->nservers == -1) |
| 177 |
{ |
| 178 |
channel->servers = |
| 179 |
malloc(options->nservers * sizeof(struct server_state)); |
| 180 |
if (!channel->servers && options->nservers != 0) |
| 181 |
return ARES_ENOMEM; |
| 182 |
for (i = 0; i < options->nservers; i++) |
| 183 |
channel->servers[i].addr = options->servers[i]; |
| 184 |
channel->nservers = options->nservers; |
| 185 |
} |
| 186 |
|
| 187 |
/* Copy the domains, if given. Keep channel->ndomains consistent so |
| 188 |
* we can clean up in case of error. |
| 189 |
*/ |
| 190 |
if ((optmask & ARES_OPT_DOMAINS) && channel->ndomains == -1) |
| 191 |
{ |
| 192 |
channel->domains = malloc(options->ndomains * sizeof(char *)); |
| 193 |
if (!channel->domains && options->ndomains != 0) |
| 194 |
return ARES_ENOMEM; |
| 195 |
for (i = 0; i < options->ndomains; i++) |
| 196 |
{ |
| 197 |
channel->ndomains = i; |
| 198 |
channel->domains[i] = strdup(options->domains[i]); |
| 199 |
if (!channel->domains[i]) |
| 200 |
return ARES_ENOMEM; |
| 201 |
} |
| 202 |
channel->ndomains = options->ndomains; |
| 203 |
} |
| 204 |
|
| 205 |
/* Set lookups, if given. */ |
| 206 |
if ((optmask & ARES_OPT_LOOKUPS) && !channel->lookups) |
| 207 |
{ |
| 208 |
channel->lookups = strdup(options->lookups); |
| 209 |
if (!channel->lookups) |
| 210 |
return ARES_ENOMEM; |
| 211 |
} |
| 212 |
|
| 213 |
return ARES_SUCCESS; |
| 214 |
} |
| 215 |
|
| 216 |
static int init_by_environment(ares_channel channel) |
| 217 |
{ |
| 218 |
const char *localdomain, *res_options; |
| 219 |
int status; |
| 220 |
|
| 221 |
localdomain = getenv("LOCALDOMAIN"); |
| 222 |
if (localdomain && channel->ndomains == -1) |
| 223 |
{ |
| 224 |
status = set_search(channel, localdomain); |
| 225 |
if (status != ARES_SUCCESS) |
| 226 |
return status; |
| 227 |
} |
| 228 |
|
| 229 |
res_options = getenv("RES_OPTIONS"); |
| 230 |
if (res_options) |
| 231 |
{ |
| 232 |
status = set_options(channel, res_options); |
| 233 |
if (status != ARES_SUCCESS) |
| 234 |
return status; |
| 235 |
} |
| 236 |
|
| 237 |
return ARES_SUCCESS; |
| 238 |
} |
| 239 |
|
| 240 |
static int init_by_resolv_conf(ares_channel channel) |
| 241 |
{ |
| 242 |
FILE *fp; |
| 243 |
char *line = NULL, *p; |
| 244 |
int linesize, status, nservers = 0, nsort = 0; |
| 245 |
struct server_state *servers = NULL; |
| 246 |
struct apattern *sortlist = NULL; |
| 247 |
|
| 248 |
fp = fopen(PATH_RESOLV_CONF, "r"); |
| 249 |
if (!fp) |
| 250 |
return (errno == ENOENT) ? ARES_SUCCESS : ARES_EFILE; |
| 251 |
while ((status = ares__read_line(fp, &line, &linesize)) == ARES_SUCCESS) |
| 252 |
{ |
| 253 |
if ((p = try_config(line, "domain")) && channel->ndomains == -1) |
| 254 |
status = config_domain(channel, p); |
| 255 |
else if ((p = try_config(line, "lookup")) && !channel->lookups) |
| 256 |
status = config_lookup(channel, p); |
| 257 |
else if ((p = try_config(line, "search")) && channel->ndomains == -1) |
| 258 |
status = set_search(channel, p); |
| 259 |
else if ((p = try_config(line, "nameserver")) && channel->nservers == -1) |
| 260 |
status = config_nameserver(&servers, &nservers, p); |
| 261 |
else if ((p = try_config(line, "sortlist")) && channel->nsort == -1) |
| 262 |
status = config_sortlist(&sortlist, &nsort, p); |
| 263 |
else if ((p = try_config(line, "options"))) |
| 264 |
status = set_options(channel, p); |
| 265 |
else |
| 266 |
status = ARES_SUCCESS; |
| 267 |
if (status != ARES_SUCCESS) |
| 268 |
break; |
| 269 |
} |
| 270 |
free(line); |
| 271 |
fclose(fp); |
| 272 |
|
| 273 |
/* Handle errors. */ |
| 274 |
if (status != ARES_EOF) |
| 275 |
{ |
| 276 |
free(servers); |
| 277 |
free(sortlist); |
| 278 |
return status; |
| 279 |
} |
| 280 |
|
| 281 |
/* If we got any name server entries, fill them in. */ |
| 282 |
if (servers) |
| 283 |
{ |
| 284 |
channel->servers = servers; |
| 285 |
channel->nservers = nservers; |
| 286 |
} |
| 287 |
|
| 288 |
/* If we got any sortlist entries, fill them in. */ |
| 289 |
if (sortlist) |
| 290 |
{ |
| 291 |
channel->sortlist = sortlist; |
| 292 |
channel->nsort = nsort; |
| 293 |
} |
| 294 |
|
| 295 |
return ARES_SUCCESS; |
| 296 |
} |
| 297 |
|
| 298 |
static int init_by_defaults(ares_channel channel) |
| 299 |
{ |
| 300 |
char hostname[MAXHOSTNAMELEN + 1]; |
| 301 |
|
| 302 |
if (channel->flags == -1) |
| 303 |
channel->flags = 0; |
| 304 |
if (channel->timeout == -1) |
| 305 |
channel->timeout = DEFAULT_TIMEOUT; |
| 306 |
if (channel->tries == -1) |
| 307 |
channel->tries = DEFAULT_TRIES; |
| 308 |
if (channel->ndots == -1) |
| 309 |
channel->ndots = 1; |
| 310 |
if (channel->udp_port == -1) |
| 311 |
channel->udp_port = htons(NS_DEFAULTPORT); |
| 312 |
if (channel->tcp_port == -1) |
| 313 |
channel->tcp_port = htons(NS_DEFAULTPORT); |
| 314 |
|
| 315 |
if (channel->nservers == -1) |
| 316 |
{ |
| 317 |
#ifdef WIN32 |
| 318 |
int buf[1024]; |
| 319 |
DWORD size; |
| 320 |
PWSTR adapter; |
| 321 |
int i; |
| 322 |
int num; |
| 323 |
|
| 324 |
size = sizeof(buf); |
| 325 |
adapter = 0; |
| 326 |
|
| 327 |
// The return values from DnsQueryConfig don't seem to be documented. |
| 328 |
// For DnsConfigDnsServerList, it returns (in buf) an array of 4 byte integers |
| 329 |
// The first one says how many ip addresses follow and can be ignored |
| 330 |
// (Using the 'size' parameter to determine number of results seems safer.) |
| 331 |
DnsQueryConfig(DnsConfigDnsServerList,FALSE,adapter,NULL,buf,&size); |
| 332 |
|
| 333 |
// assume only IPv4 address |
| 334 |
assert( size%4 == 0 ); |
| 335 |
num = size/4; |
| 336 |
assert( num > 1 ); // (num - 1) is how many DNS servers are configured |
| 337 |
|
| 338 |
channel->servers = malloc( (num-1) * sizeof(struct server_state)); |
| 339 |
if (!channel->servers) |
| 340 |
{ |
| 341 |
return ARES_ENOMEM; |
| 342 |
} |
| 343 |
|
| 344 |
channel->nservers = 0; |
| 345 |
for ( i=1; i< num ; i++ ) |
| 346 |
{ |
| 347 |
channel->servers[ channel->nservers++ ].addr.s_addr = ( buf[i] ); |
| 348 |
} |
| 349 |
|
| 350 |
// channel->servers[0].addr.s_addr = inet_addr("10.0.1.1"); |
| 351 |
#else |
| 352 |
|
| 353 |
/* If nobody specified servers, try a local named. */ |
| 354 |
channel->servers = malloc(sizeof(struct server_state)); |
| 355 |
if (!channel->servers) |
| 356 |
return ARES_ENOMEM; |
| 357 |
channel->servers[0].addr.s_addr = htonl(INADDR_LOOPBACK); |
| 358 |
channel->nservers = 1; |
| 359 |
#endif |
| 360 |
|
| 361 |
} |
| 362 |
|
| 363 |
if (channel->ndomains == -1) |
| 364 |
{ |
| 365 |
/* Derive a default domain search list from the kernel hostname, |
| 366 |
* or set it to empty if the hostname isn't helpful. |
| 367 |
*/ |
| 368 |
if (gethostname(hostname, sizeof(hostname)) == -1 |
| 369 |
|| !strchr(hostname, '.')) |
| 370 |
{ |
| 371 |
channel->domains = 0; // malloc(0); |
| 372 |
channel->ndomains = 0; |
| 373 |
} |
| 374 |
else |
| 375 |
{ |
| 376 |
channel->domains = malloc(sizeof(char *)); |
| 377 |
if (!channel->domains) |
| 378 |
return ARES_ENOMEM; |
| 379 |
channel->ndomains = 0; |
| 380 |
channel->domains[0] = strdup(strchr(hostname, '.') + 1); |
| 381 |
if (!channel->domains[0]) |
| 382 |
return ARES_ENOMEM; |
| 383 |
channel->ndomains = 1; |
| 384 |
} |
| 385 |
} |
| 386 |
|
| 387 |
if (channel->nsort == -1) |
| 388 |
{ |
| 389 |
channel->sortlist = NULL; |
| 390 |
channel->nsort = 0; |
| 391 |
} |
| 392 |
|
| 393 |
if (!channel->lookups) |
| 394 |
{ |
| 395 |
channel->lookups = strdup("bf"); |
| 396 |
if (!channel->lookups) |
| 397 |
return ARES_ENOMEM; |
| 398 |
} |
| 399 |
|
| 400 |
return ARES_SUCCESS; |
| 401 |
} |
| 402 |
|
| 403 |
static int config_domain(ares_channel channel, char *str) |
| 404 |
{ |
| 405 |
char *q; |
| 406 |
|
| 407 |
/* Set a single search domain. */ |
| 408 |
q = str; |
| 409 |
while (*q && !isspace((unsigned char)*q)) |
| 410 |
q++; |
| 411 |
*q = 0; |
| 412 |
return set_search(channel, str); |
| 413 |
} |
| 414 |
|
| 415 |
static int config_lookup(ares_channel channel, const char *str) |
| 416 |
{ |
| 417 |
char lookups[3], *l; |
| 418 |
const char *p; |
| 419 |
|
| 420 |
/* Set the lookup order. Only the first letter of each work |
| 421 |
* is relevant, and it has to be "b" for DNS or "f" for the |
| 422 |
* host file. Ignore everything else. |
| 423 |
*/ |
| 424 |
l = lookups; |
| 425 |
p = str; |
| 426 |
while (*p) |
| 427 |
{ |
| 428 |
if ((*p == 'b' || *p == 'f') && l < lookups + 2) |
| 429 |
*l++ = *p; |
| 430 |
while (*p && !isspace((unsigned char)*p)) |
| 431 |
p++; |
| 432 |
while (isspace((unsigned char)*p)) |
| 433 |
p++; |
| 434 |
} |
| 435 |
*l = 0; |
| 436 |
channel->lookups = strdup(lookups); |
| 437 |
return (channel->lookups) ? ARES_SUCCESS : ARES_ENOMEM; |
| 438 |
} |
| 439 |
|
| 440 |
static int config_nameserver(struct server_state **servers, int *nservers, |
| 441 |
const char *str) |
| 442 |
{ |
| 443 |
struct in_addr addr; |
| 444 |
struct server_state *newserv; |
| 445 |
|
| 446 |
/* Add a nameserver entry, if this is a valid address. */ |
| 447 |
addr.s_addr = inet_addr(str); |
| 448 |
if (addr.s_addr == INADDR_NONE) |
| 449 |
return ARES_SUCCESS; |
| 450 |
newserv = realloc(*servers, (*nservers + 1) * sizeof(struct server_state)); |
| 451 |
if (!newserv) |
| 452 |
return ARES_ENOMEM; |
| 453 |
newserv[*nservers].addr = addr; |
| 454 |
*servers = newserv; |
| 455 |
(*nservers)++; |
| 456 |
return ARES_SUCCESS; |
| 457 |
} |
| 458 |
|
| 459 |
static int config_sortlist(struct apattern **sortlist, int *nsort, |
| 460 |
const char *str) |
| 461 |
{ |
| 462 |
struct apattern pat, *newsort; |
| 463 |
const char *q; |
| 464 |
|
| 465 |
/* Add sortlist entries. */ |
| 466 |
while (*str && *str != ';') |
| 467 |
{ |
| 468 |
q = str; |
| 469 |
while (*q && *q != '/' && *q != ';' && !isspace((unsigned char)*q)) |
| 470 |
q++; |
| 471 |
if (ip_addr(str, q - str, &pat.addr) == 0) |
| 472 |
{ |
| 473 |
/* We have a pattern address; now determine the mask. */ |
| 474 |
if (*q == '/') |
| 475 |
{ |
| 476 |
str = q + 1; |
| 477 |
while (*q && *q != ';' && !isspace((unsigned char)*q)) |
| 478 |
q++; |
| 479 |
if (ip_addr(str, q - str, &pat.mask) != 0) |
| 480 |
natural_mask(&pat); |
| 481 |
} |
| 482 |
else |
| 483 |
natural_mask(&pat); |
| 484 |
|
| 485 |
/* Add this pattern to our list. */ |
| 486 |
newsort = realloc(*sortlist, (*nsort + 1) * sizeof(struct apattern)); |
| 487 |
if (!newsort) |
| 488 |
return ARES_ENOMEM; |
| 489 |
newsort[*nsort] = pat; |
| 490 |
*sortlist = newsort; |
| 491 |
(*nsort)++; |
| 492 |
} |
| 493 |
else |
| 494 |
{ |
| 495 |
while (*q && *q != ';' && !isspace((unsigned char)*q)) |
| 496 |
q++; |
| 497 |
} |
| 498 |
str = q; |
| 499 |
while (isspace((unsigned char)*str)) |
| 500 |
str++; |
| 501 |
} |
| 502 |
|
| 503 |
return ARES_SUCCESS; |
| 504 |
} |
| 505 |
|
| 506 |
static int set_search(ares_channel channel, const char *str) |
| 507 |
{ |
| 508 |
int n; |
| 509 |
const char *p, *q; |
| 510 |
|
| 511 |
/* Count the domains given. */ |
| 512 |
n = 0; |
| 513 |
p = str; |
| 514 |
while (*p) |
| 515 |
{ |
| 516 |
while (*p && !isspace((unsigned char)*p)) |
| 517 |
p++; |
| 518 |
while (isspace((unsigned char)*p)) |
| 519 |
p++; |
| 520 |
n++; |
| 521 |
} |
| 522 |
|
| 523 |
channel->domains = malloc(n * sizeof(char *)); |
| 524 |
if (!channel->domains && n) |
| 525 |
return ARES_ENOMEM; |
| 526 |
|
| 527 |
/* Now copy the domains. */ |
| 528 |
n = 0; |
| 529 |
p = str; |
| 530 |
while (*p) |
| 531 |
{ |
| 532 |
channel->ndomains = n; |
| 533 |
q = p; |
| 534 |
while (*q && !isspace((unsigned char)*q)) |
| 535 |
q++; |
| 536 |
channel->domains[n] = malloc(q - p + 1); |
| 537 |
if (!channel->domains[n]) |
| 538 |
return ARES_ENOMEM; |
| 539 |
memcpy(channel->domains[n], p, q - p); |
| 540 |
channel->domains[n][q - p] = 0; |
| 541 |
p = q; |
| 542 |
while (isspace((unsigned char)*p)) |
| 543 |
p++; |
| 544 |
n++; |
| 545 |
} |
| 546 |
channel->ndomains = n; |
| 547 |
|
| 548 |
return ARES_SUCCESS; |
| 549 |
} |
| 550 |
|
| 551 |
static int set_options(ares_channel channel, const char *str) |
| 552 |
{ |
| 553 |
const char *p, *q, *val; |
| 554 |
|
| 555 |
p = str; |
| 556 |
while (*p) |
| 557 |
{ |
| 558 |
q = p; |
| 559 |
while (*q && !isspace((unsigned char)*q)) |
| 560 |
q++; |
| 561 |
val = try_option(p, q, "ndots:"); |
| 562 |
if (val && channel->ndots == -1) |
| 563 |
channel->ndots = atoi(val); |
| 564 |
val = try_option(p, q, "retrans:"); |
| 565 |
if (val && channel->timeout == -1) |
| 566 |
channel->timeout = atoi(val); |
| 567 |
val = try_option(p, q, "retry:"); |
| 568 |
if (val && channel->tries == -1) |
| 569 |
channel->tries = atoi(val); |
| 570 |
p = q; |
| 571 |
while (isspace((unsigned char)*p)) |
| 572 |
p++; |
| 573 |
} |
| 574 |
|
| 575 |
return ARES_SUCCESS; |
| 576 |
} |
| 577 |
|
| 578 |
static char *try_config(char *s, char *opt) |
| 579 |
{ |
| 580 |
int len; |
| 581 |
|
| 582 |
len = strlen(opt); |
| 583 |
if (strncmp(s, opt, len) != 0 || !isspace((unsigned char)s[len])) |
| 584 |
return NULL; |
| 585 |
s += len; |
| 586 |
while (isspace((unsigned char)*s)) |
| 587 |
s++; |
| 588 |
return s; |
| 589 |
} |
| 590 |
|
| 591 |
static const char *try_option(const char *p, const char *q, const char *opt) |
| 592 |
{ |
| 593 |
int len; |
| 594 |
|
| 595 |
len = strlen(opt); |
| 596 |
return (q - p > len && strncmp(p, opt, len) == 0) ? p + len : NULL; |
| 597 |
} |
| 598 |
|
| 599 |
static int ip_addr(const char *s, int len, struct in_addr *addr) |
| 600 |
{ |
| 601 |
char ipbuf[16]; |
| 602 |
|
| 603 |
/* Four octets and three periods yields at most 15 characters. */ |
| 604 |
if (len > 15) |
| 605 |
return -1; |
| 606 |
memcpy(ipbuf, s, len); |
| 607 |
ipbuf[len] = 0; |
| 608 |
|
| 609 |
addr->s_addr = inet_addr(ipbuf); |
| 610 |
if (addr->s_addr == INADDR_NONE && strcmp(ipbuf, "255.255.255.255") != 0) |
| 611 |
return -1; |
| 612 |
return 0; |
| 613 |
} |
| 614 |
|
| 615 |
static void natural_mask(struct apattern *pat) |
| 616 |
{ |
| 617 |
struct in_addr addr; |
| 618 |
|
| 619 |
/* Store a host-byte-order copy of pat in a struct in_addr. Icky, |
| 620 |
* but portable. |
| 621 |
*/ |
| 622 |
addr.s_addr = ntohl(pat->addr.s_addr); |
| 623 |
|
| 624 |
/* This is out of date in the CIDR world, but some people might |
| 625 |
* still rely on it. |
| 626 |
*/ |
| 627 |
if (IN_CLASSA(addr.s_addr)) |
| 628 |
pat->mask.s_addr = htonl(IN_CLASSA_NET); |
| 629 |
else if (IN_CLASSB(addr.s_addr)) |
| 630 |
pat->mask.s_addr = htonl(IN_CLASSB_NET); |
| 631 |
else |
| 632 |
pat->mask.s_addr = htonl(IN_CLASSC_NET); |
| 633 |
} |
Parent Directory
| 
Revision Log