diff options
Diffstat (limited to 'lib/base/dns.cpp')
| -rw-r--r-- | lib/base/dns.cpp | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/lib/base/dns.cpp b/lib/base/dns.cpp new file mode 100644 index 00000000..f9e38886 --- /dev/null +++ b/lib/base/dns.cpp @@ -0,0 +1,176 @@ +/** BEGIN COPYRIGHT BLOCK + * Copyright 2001 Sun Microsystems, Inc. + * Portions copyright 1999, 2001-2003 Netscape Communications Corporation. + * All rights reserved. + * END COPYRIGHT BLOCK **/ +/* + * dns.c: DNS resolution routines + * + * Rob McCool + */ +#define DNS_GUESSING + +#include "netsite.h" +#ifdef XP_UNIX +#include "systems.h" +#else /* XP_WIN32 */ +#include "base/systems.h" +#endif /* XP_WIN32 */ + +#include "net.h" /* SYS_NETFD, various headers to do DNS */ + +/* Under NT, these are taken care of by net.h including winsock.h */ +#ifdef XP_UNIX +#include <arpa/inet.h> /* inet_ntoa */ +#include <netdb.h> /* struct hostent */ +#ifdef NEED_GHN_PROTO +extern "C" int gethostname (char *name, size_t namelen); +#endif +#endif +#ifdef DNS_CACHE +#include "base/dns_cache.h" +#include "base/ereport.h" +#endif /* DNS_CACHE */ +#include <stdio.h> +#include <nspr.h> +#include "frame/conf.h" + +/* ---------------------------- dns_find_fqdn ----------------------------- */ + + +/* defined in dnsdmain.c */ +extern "C" NSAPI_PUBLIC char *dns_guess_domain(char * hname); + +char *net_find_fqdn(PRHostEnt *p) +{ + int x; + + if((!p->h_name) || (!p->h_aliases)) + return NULL; + + if(!strchr(p->h_name, '.')) { + for(x = 0; p->h_aliases[x]; ++x) { + if((strchr(p->h_aliases[x], '.')) && + (!strncmp(p->h_aliases[x], p->h_name, strlen(p->h_name)))) + { + return STRDUP(p->h_aliases[x]); + } + } +#ifdef DNS_GUESSING + return dns_guess_domain(p->h_name); +#else + return NULL; +#endif /* DNS_GUESSING */ + } + else + return STRDUP(p->h_name); +} + + +/* ----------------------------- dns_ip2host ------------------------------ */ + + +char *dns_ip2host(char *ip, int verify) +{ + /* struct in_addr iaddr; */ + PRNetAddr iaddr; + char *hn; +#ifdef DNS_CACHE + dns_cache_entry_t *dns_entry; +#endif + static unsigned long laddr = 0; + static char myhostname[256]; + PRHostEnt hent; + char buf[PR_NETDB_BUF_SIZE]; + PRStatus err; + + + err = PR_InitializeNetAddr(PR_IpAddrNull, 0, &iaddr); + + if((iaddr.inet.ip = inet_addr(ip)) == -1) + goto bong; + +#ifdef DNS_CACHE + if ( (dns_entry = dns_cache_lookup_ip((unsigned int)iaddr.inet.ip)) ) { + hn = NULL; + if ( dns_entry->host && + /* Only use entry if the cache entry has been verified or if + * verify is off... + */ + (dns_entry->verified || !verify) ) { + hn = STRDUP( dns_entry->host ); + (void)dns_cache_use_decrement(dns_entry); + return hn; + } + dns_cache_delete(dns_entry); + dns_entry = 0; + } +#endif + + /* + * See if it happens to be the localhost IP address, and try + * the local host name if so. + */ + if (laddr == 0) { + laddr = inet_addr("127.0.0.1"); + myhostname[0] = 0; + PR_GetSystemInfo(PR_SI_HOSTNAME, myhostname, sizeof(myhostname)); + } + + /* Have to match the localhost IP address and have a hostname */ + if ((iaddr.inet.ip == laddr) && (myhostname[0] != 0)) { + /* + * Now try for a fully-qualified domain name, starting with + * the local hostname. + */ + err = PR_GetHostByName(myhostname, + buf, + PR_NETDB_BUF_SIZE, + &hent); + + /* Don't verify if we get a fully-qualified name this way */ + verify = 0; + } + else { + err = PR_GetHostByAddr(&iaddr, + buf, + PR_NETDB_BUF_SIZE, + &hent); + } + + if ((err == PR_FAILURE) || !(hn = net_find_fqdn(&hent))) goto bong; + + + if(verify) { + char **haddr = 0; + err = PR_GetHostByName(hn, + buf, + PR_NETDB_BUF_SIZE, + &hent); + + if(err == PR_SUCCESS) { + for(haddr = hent.h_addr_list; *haddr; haddr++) { + if(((struct in_addr *)(*haddr))->s_addr == iaddr.inet.ip) + break; + } + } + + if((err == PR_FAILURE) || (!(*haddr))) + goto bong; + } + +#ifdef DNS_CACHE + if ( (dns_entry = dns_cache_insert(hn, (unsigned int)iaddr.inet.ip, verify)) ) { + (void) dns_cache_use_decrement(dns_entry); + } +#endif /* DNS_CACHE */ + return hn; + bong: +#ifdef DNS_CACHE + /* Insert the lookup failure */ + if ( (dns_entry = dns_cache_insert(NULL, (unsigned int)iaddr.inet.ip, verify)) ) { + (void) dns_cache_use_decrement(dns_entry); + } +#endif /* DNS_CACHE */ + return NULL; +} |