#include <pthread.h>
#include "stdio_impl.h"
#include "syscall.h"
+#include "lookup.h"
static void cleanup(void *p)
{
FILE *f, _f;
unsigned char _buf[256];
char line[64], *s, *z;
- int timeout = 5000, attempts = 2, retry_interval;
+ int timeout = 5000, attempts = 2, retry_interval, servfail_retry;
union {
struct sockaddr_in sin;
struct sockaddr_in6 sin6;
int cs;
struct pollfd pfd;
unsigned long t0, t1, t2;
+ struct address iplit;
pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
for (z=s; *z && !isspace(*z); z++);
*z=0;
- if (inet_pton(AF_INET, s, &ns[nns].sin.sin_addr)>0) {
- ns[nns].sin.sin_port = htons(53);
- ns[nns++].sin.sin_family = AF_INET;
- } else if (inet_pton(AF_INET6, s, &ns[nns].sin6.sin6_addr)>0) {
- sl = sizeof sa.sin6;
- ns[nns].sin6.sin6_port = htons(53);
- ns[nns++].sin6.sin6_family = family = AF_INET6;
+ if (__lookup_ipliteral(&iplit, s, AF_UNSPEC)>0) {
+ if (iplit.family == AF_INET) {
+ memcpy(&ns[nns].sin.sin_addr, iplit.addr, 4);
+ ns[nns].sin.sin_port = htons(53);
+ ns[nns++].sin.sin_family = AF_INET;
+ } else {
+ sl = sizeof sa.sin6;
+ memcpy(&ns[nns].sin6.sin6_addr, iplit.addr, 16);
+ ns[nns].sin6.sin6_port = htons(53);
+ ns[nns].sin6.sin6_scope_id = iplit.scopeid;
+ ns[nns++].sin6.sin6_family = family = AF_INET6;
+ }
}
}
if (f) __fclose_ca(f);
pfd.fd = fd;
pfd.events = POLLIN;
retry_interval = timeout / attempts;
+ next = 0;
t0 = t2 = mtime();
t1 = t2 - retry_interval;
qlens[i], MSG_NOSIGNAL,
(void *)&ns[j], sl);
t1 = t2;
+ servfail_retry = 2 * nqueries;
}
/* Wait for a response, or until time to retry */
while ((rlen = recvfrom(fd, answers[next], asize, 0,
(void *)&sa, (socklen_t[1]){sl})) >= 0) {
- /* Ignore non-identifiable packets (no query id) */
- if (rlen < 2) continue;
+ /* Ignore non-identifiable packets */
+ if (rlen < 4) continue;
/* Ignore replies from addresses we didn't send to */
- for (i=0; i<nns && memcmp(ns+i, &sa, sl); i++);
- if (i==nns) continue;
+ for (j=0; j<nns && memcmp(ns+j, &sa, sl); j++);
+ if (j==nns) continue;
/* Find which query this answer goes with, if any */
for (i=next; i<nqueries && (
if (i==nqueries) continue;
if (alens[i]) continue;
+ /* Only accept positive or negative responses;
+ * retry immediately on server failure, and ignore
+ * all other codes such as refusal. */
+ switch (answers[next][3] & 15) {
+ case 0:
+ case 3:
+ break;
+ case 2:
+ if (servfail_retry && servfail_retry--)
+ sendto(fd, queries[i],
+ qlens[i], MSG_NOSIGNAL,
+ (void *)&ns[j], sl);
+ default:
+ continue;
+ }
+
/* Store answer in the right slot, or update next
* available temp slot if it's already in place. */
alens[i] = rlen;