#include <ctype.h>
#include <unistd.h>
#include <pthread.h>
+#include <errno.h>
#include "__dns.h"
#include "stdio_impl.h"
time_t t0 = time(0);
int fd;
FILE *f, _f;
- unsigned char _buf[64];
+ unsigned char _buf[256];
char line[64], *s, *z;
union {
struct sockaddr_in sin;
struct sockaddr_in6 sin6;
} sa = {0}, ns[3] = {{0}};
- socklen_t sl;
+ socklen_t sl = sizeof sa.sin;
int nns = 0;
- int family = AF_UNSPEC;
+ int family = AF_INET;
unsigned char q[280] = "", *r = dest;
int ql;
int rlen;
for (s=line+11; isspace(*s); s++);
for (z=s; *z && !isspace(*z); z++);
*z=0;
- if (__ipparse(ns+nns, family, s) < 0) continue;
+ if (__ipparse(ns+nns, AF_UNSPEC, s) < 0) continue;
ns[nns].sin.sin_port = htons(53);
- family = ns[nns++].sin.sin_family;
- sl = family==AF_INET6 ? sizeof sa.sin6 : sizeof sa.sin;
+ if (ns[nns++].sin.sin_family == AF_INET6) {
+ family = AF_INET6;
+ sl = sizeof sa.sin6;
+ }
}
if (f) __fclose_ca(f);
if (!nns) {
sl = sizeof sa.sin;
}
+ /* Get local address and open/bind a socket */
+ sa.sin.sin_family = family;
+ fd = socket(family, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+
+ /* Handle case where system lacks IPv6 support */
+ if (fd < 0 && errno == EAFNOSUPPORT) {
+ if (family != AF_INET6) return EAI_SYSTEM;
+ fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
+ family = AF_INET;
+ }
+ if (fd < 0) return EAI_SYSTEM;
+
+ /* Convert any IPv4 addresses in a mixed environment to v4-mapped */
+ if (family == AF_INET6) {
+ setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &(int){0}, sizeof 0);
+ for (i=0; i<nns; i++) {
+ if (ns[i].sin.sin_family != AF_INET) continue;
+ memcpy(ns[i].sin6.sin6_addr.s6_addr+12,
+ &ns[i].sin.sin_addr, 4);
+ memcpy(ns[i].sin6.sin6_addr.s6_addr,
+ "\0\0\0\0\0\0\0\0\0\0\xff\xff", 12);
+ ns[i].sin6.sin6_family = AF_INET6;
+ ns[i].sin6.sin6_flowinfo = 0;
+ ns[i].sin6.sin6_scope_id = 0;
+ }
+ }
+
pthread_cleanup_push(cleanup, (void *)(intptr_t)fd);
pthread_setcancelstate(cs, 0);
- /* Get local address and open/bind a socket */
- sa.sin.sin_family = family;
- fd = socket(family, SOCK_DGRAM, 0);
if (bind(fd, (void *)&sa, sl) < 0) {
errcode = EAI_SYSTEM;
goto out;
}
- /* Nonblocking to work around Linux UDP select bug */
- fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK);
pfd.fd = fd;
pfd.events = POLLIN;
return __dns_doqueries(r, a, rr, rrcnt);
}
-
-#define BITOP(a,b,op) \
- ((a)[(size_t)(b)/(8*sizeof *(a))] op (size_t)1<<((size_t)(b)%(8*sizeof *(a))))
-
-static int decname(char *s, const unsigned char *b, const unsigned char *p)
-{
- /* Remember jump destinations to detect loops and abort */
- size_t seen[PACKET_MAX/8/sizeof(size_t)] = { 0 };
- char *sz = s + HOST_NAME_MAX;
- const unsigned char *pz = b+512;
- for (;;) {
- if (p>=pz) return -1;
- else if (*p&0xc0) {
- int j = (p[0]&1) | p[1];
- if (BITOP(seen, j, &)) return -1;
- BITOP(seen, j, |=);
- p = b + j;
- } else if (*p) {
- if (p+*p+1>=pz || s+*p>=sz) return -1;
- memcpy(s, p+1, *p);
- s += *p+1;
- p += *p+1;
- s[-1] = *p ? '.' : 0;
- } else return 0;
- }
-}
+int __dn_expand(const unsigned char *, const unsigned char *, const unsigned char *, char *, int);
int __dns_get_rr(void *dest, size_t stride, size_t maxlen, size_t limit, const unsigned char *r, int rr, int dec)
{
len = p[8]*256 + p[9];
if (p+len > r+512) return -1;
if (p[1]==rr && len <= maxlen) {
- if (dec && decname(tmp, r, p+10)<0) return -1;
+ if (dec && __dn_expand(r, r+512, p+10, tmp, sizeof tmp)<0)
+ return -1;
if (dest && limit) {
if (dec) strcpy(dest, tmp);
else memcpy(dest, p+10, len);