From 2766c6bb69ced7c4f33ec9d8bda56ba5b66e2915 Mon Sep 17 00:00:00 2001 From: Guillaume Cottenceau Date: Sat, 16 Dec 2000 22:03:06 +0000 Subject: - network/nfs works --- mdk-stage1/dns.c | 154 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 154 insertions(+) create mode 100644 mdk-stage1/dns.c (limited to 'mdk-stage1/dns.c') diff --git a/mdk-stage1/dns.c b/mdk-stage1/dns.c new file mode 100644 index 000000000..ca750536a --- /dev/null +++ b/mdk-stage1/dns.c @@ -0,0 +1,154 @@ +/* + * Guillaume Cottenceau (gc@mandrakesoft.com) + * + * Copyright 2000 MandrakeSoft + * + * This software may be freely redistributed under the terms of the GNU + * public license. + * + * 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., 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ + +/* + * Portions from Erik Troan (ewt@redhat.com) + * + * Copyright 1996 Red Hat Software + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "log.h" + +#include "dns.h" + +/* This is dumb, but glibc doesn't like to do hostname lookups w/o libc.so */ + +union dns_response { + HEADER hdr; + u_char buf[PACKETSZ]; +} ; + +static int do_query(char * query, int queryType, char ** domainName, struct in_addr * ipNum) +{ + int len, ancount, type; + u_char * data, * end; + char name[MAXDNAME]; + union dns_response response; + +#ifdef __sparc__ + /* from jj: */ + /* We have to wait till ethernet negotiation is done */ + _res.retry = 3; +#else + _res.retry = 2; +#endif + + + len = res_search(query, C_IN, queryType, (void *) &response, sizeof(response)); + if (len <= 0) + return -1; + + if (ntohs(response.hdr.rcode) != NOERROR) + return -1; + + ancount = ntohs(response.hdr.ancount); + if (ancount < 1) + return -1; + + data = response.buf + sizeof(HEADER); + end = response.buf + len; + + /* skip the question */ + data += dn_skipname(data, end) + QFIXEDSZ; + + /* parse the answer(s) */ + while (--ancount >= 0 && data < end) { + + /* skip the domain name portion of the RR record */ + data += dn_skipname(data, end); + + /* get RR information */ + GETSHORT(type, data); + data += INT16SZ; /* skipp class */ + data += INT32SZ; /* skipp TTL */ + GETSHORT(len, data); + + if (type == T_PTR) { + /* we got a pointer */ + len = dn_expand(response.buf, end, data, name, sizeof(name)); + if (len <= 0) return -1; + if (queryType == T_PTR && domainName) { + /* we wanted a pointer */ + *domainName = malloc(strlen(name) + 1); + strcpy(*domainName, name); + return 0; + } + } else if (type == T_A) { + /* we got an address */ + if (queryType == T_A && ipNum) { + /* we wanted an address */ + memcpy(ipNum, data, sizeof(*ipNum)); + return 0; + } + } + + /* move ahead to next RR */ + data += len; + } + + return -1; +} + +char * mygethostbyaddr(char * ipnum) { + int rc; + char * result; + char * strbuf; + char * chptr; + char * splits[4]; + int i; + + _res.retry = 1; + + strbuf = alloca(strlen(ipnum) + 1); + strcpy(strbuf, ipnum); + + ipnum = alloca(strlen(strbuf) + 20); + + for (i = 0; i < 4; i++) { + chptr = strbuf; + while (*chptr && *chptr != '.') + chptr++; + *chptr = '\0'; + + if (chptr - strbuf > 3) return NULL; + splits[i] = strbuf; + strbuf = chptr + 1; + } + + sprintf(ipnum, "%s.%s.%s.%s.in-addr.arpa", splits[3], splits[2], splits[1], splits[0]); + + rc = do_query(ipnum, T_PTR, &result, NULL); + + if (rc) + return NULL; + else + return result; +} + +int mygethostbyname(char * name, struct in_addr * addr) { + int rc = do_query(name, T_A, NULL, addr); + if (!rc) + log_message("%s is-at %s", name, inet_ntoa(*addr)); + return rc; +} -- cgit v1.2.1