diff options
Diffstat (limited to 'mdk-stage1')
-rw-r--r-- | mdk-stage1/dns.c | 138 | ||||
-rw-r--r-- | mdk-stage1/dns.h | 6 |
2 files changed, 19 insertions, 125 deletions
diff --git a/mdk-stage1/dns.c b/mdk-stage1/dns.c index ca750536a..054001c58 100644 --- a/mdk-stage1/dns.c +++ b/mdk-stage1/dns.c @@ -19,136 +19,30 @@ * */ -#include <alloca.h> -#include <sys/socket.h> -#include <netinet/in.h> -#include <resolv.h> -#include <arpa/nameser.h> -#include <arpa/inet.h> #include <stdlib.h> +#include <unistd.h> #include <string.h> +#include <stdio.h> +#include "network.h" #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) +// needs a wrapper since gethostbyname from dietlibc doesn't support domain handling +struct hostent *mygethostbyname(const char *name) { - 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) + char fully_qualified[500]; + struct hostent * h; + h = gethostbyname(name); + if (h) + return h; + if (!domain) 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; + sprintf(fully_qualified, "%s.%s", name, domain); + h = gethostbyname(fully_qualified); + if (!h) + log_message("unknown host %s", name); + return h; } diff --git a/mdk-stage1/dns.h b/mdk-stage1/dns.h index 97af9c08a..8506db923 100644 --- a/mdk-stage1/dns.h +++ b/mdk-stage1/dns.h @@ -22,9 +22,9 @@ #ifndef H_DNS #define H_DNS -#include <netinet/in.h> +#include <netdb.h> -int mygethostbyname(char * name, struct in_addr * addr); -char * mygethostbyaddr(char * ipnum); +// needs a wrapper since gethostbyname from dietlibc doesn't support domain handling +struct hostent *mygethostbyname(const char *name); #endif |