/* * $Id: dns.cc,v 1.100 2007/04/28 22:26:37 hno Exp $ * * DEBUG: section 34 Dnsserver interface * AUTHOR: Harvest Derived * * SQUID Web Proxy Cache http://www.squid-cache.org/ * ---------------------------------------------------------- * * Squid is the result of efforts by numerous individuals from * the Internet community; see the CONTRIBUTORS file for full * details. Many organizations have provided support for Squid's * development; see the SPONSORS file for full details. Squid is * Copyrighted (C) 2001 by the Regents of the University of * California; see the COPYRIGHT file for full details. Squid * incorporates software developed and/or copyrighted by other * sources; see the CREDITS file for full details. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA. * */ #include "squid.h" #include "Store.h" #include "wordlist.h" #include "SquidTime.h" #include "CacheManager.h" #include "helper.h" /* MS VisualStudio Projects are monolitich, so we need the following #if to include the external DNS code in compile process when using external DNS. */ #if USE_DNSSERVERS static helper *dnsservers = NULL; static void dnsStats(StoreEntry * sentry) { storeAppendPrintf(sentry, "Dnsserver Statistics:\n"); helperStats(sentry, dnsservers); } void dnsInit(void) { wordlist *w; if (!Config.Program.dnsserver) return; if (dnsservers == NULL) dnsservers = helperCreate("dnsserver"); dnsservers->n_to_start = Config.dnsChildren; dnsservers->ipc_type = IPC_STREAM; assert(dnsservers->cmdline == NULL); wordlistAdd(&dnsservers->cmdline, Config.Program.dnsserver); if (Config.onoff.res_defnames) wordlistAdd(&dnsservers->cmdline, "-D"); for (w = Config.dns_nameservers; w != NULL; w = w->next) { wordlistAdd(&dnsservers->cmdline, "-s"); wordlistAdd(&dnsservers->cmdline, w->key); } helperOpenServers(dnsservers); } void dnsRegisterWithCacheManager(CacheManager & manager) { manager.registerAction("dns", "Dnsserver Statistics", dnsStats, 0, 1); } void dnsShutdown(void) { if (!dnsservers) return; helperShutdown(dnsservers); wordlistDestroy(&dnsservers->cmdline); if (!shutting_down) return; helperFree(dnsservers); dnsservers = NULL; } void dnsSubmit(const char *lookup, HLPCB * callback, void *data) { char buf[256]; static time_t first_warn = 0; snprintf(buf, 256, "%s\n", lookup); if (dnsservers->stats.queue_size >= dnsservers->n_running * 2) { if (first_warn == 0) first_warn = squid_curtime; if (squid_curtime - first_warn > 3 * 60) fatal("DNS servers not responding for 3 minutes"); debugs(34, 1, "dnsSubmit: queue overload, rejecting " << lookup); callback(data, (char *)"$fail Temporary network problem, please retry later"); return; } first_warn = 0; helperSubmit(dnsservers, buf, callback, data); } #ifdef SQUID_SNMP /* * The function to return the DNS via SNMP */ variable_list * snmp_netDnsFn(variable_list * Var, snint * ErrP) { variable_list *Answer = NULL; debugs(49, 5, "snmp_netDnsFn: Processing request: " << Var->name[LEN_SQ_NET + 1]); snmpDebugOid(5, Var->name, Var->name_length); *ErrP = SNMP_ERR_NOERROR; switch (Var->name[LEN_SQ_NET + 1]) { case DNS_REQ: Answer = snmp_var_new_integer(Var->name, Var->name_length, dnsservers->stats.requests, SMI_COUNTER32); break; case DNS_REP: Answer = snmp_var_new_integer(Var->name, Var->name_length, dnsservers->stats.replies, SMI_COUNTER32); break; case DNS_SERVERS: Answer = snmp_var_new_integer(Var->name, Var->name_length, dnsservers->n_running, SMI_COUNTER32); break; default: *ErrP = SNMP_ERR_NOSUCHNAME; break; } return Answer; } #endif /*SQUID_SNMP */ #endif /* USE_DNSSERVERS */