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#include <unistd.h>
#include "byte.h"
#include "case.h"
#include "dns.h"
#include "open.h"
#include "cdb.h"
#include "response.h"
const char *fatal = "pickdns: fatal: ";
const char *starting = "starting pickdns\n";
static char seed[128];
void initialize(void)
{
dns_random_init(seed);
}
static struct cdb c;
static char key[258];
static char data[512];
static int doit(char *q,char qtype[2],char ip[16])
{
int r;
uint32 dlen;
unsigned int qlen;
int flaga;
int flagmx;
qlen = dns_domain_length(q);
if (qlen > 255) return 0; /* impossible */
flaga = byte_equal(qtype,2,DNS_T_A);
flagmx = byte_equal(qtype,2,DNS_T_MX);
if (byte_equal(qtype,2,DNS_T_ANY)) flaga = flagmx = 1;
if (!flaga && !flagmx) goto REFUSE;
key[0] = '%';
byte_copy(key + 1,4,ip+12);
r = cdb_find(&c,key,5);
if (!r) r = cdb_find(&c,key,4);
if (!r) r = cdb_find(&c,key,3);
if (!r) r = cdb_find(&c,key,2);
if (r == -1) return 0;
key[0] = '+';
byte_zero(key + 1,2);
if (r && (cdb_datalen(&c) == 2))
if (cdb_read(&c,key + 1,2,cdb_datapos(&c)) == -1) return 0;
byte_copy(key + 3,qlen,q);
case_lowerb(key + 3,qlen + 3);
r = cdb_find(&c,key,qlen + 3);
if (!r) {
byte_zero(key + 1,2);
r = cdb_find(&c,key,qlen + 3);
}
if (!r) goto REFUSE;
if (r == -1) return 0;
dlen = cdb_datalen(&c);
if (dlen > 512) dlen = 512;
if (cdb_read(&c,data,dlen,cdb_datapos(&c)) == -1) return 0;
if (flaga) {
dns_sortip(data,dlen);
if (dlen > 12) dlen = 12;
while (dlen >= 4) {
dlen -= 4;
if (!response_rstart(q,DNS_T_A,5)) return 0;
if (!response_addbytes(data + dlen,4)) return 0;
response_rfinish(RESPONSE_ANSWER);
}
}
return 1;
REFUSE:
response[2] &= ~4;
response[3] &= ~15;
response[3] |= 5;
return 1;
}
int respond(char *q,char qtype[2],char ip[16])
{
int fd;
int result;
fd = open_read("data.cdb");
if (fd == -1) return 0;
cdb_init(&c,fd);
result = doit(q,qtype,ip);
cdb_free(&c);
close(fd);
return result;
}
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