/*
* Fill the hostent from the given DNS packet.
*/
static int
hostent_from_packet(struct hostent *h, int action, char *pkt, size_t pktlen)
{
struct packed p;
struct header hdr;
struct query q;
struct rr rr;
int r;
packed_init(&p, pkt, pktlen);
unpack_header(&p, &hdr);
for(; hdr.qdcount; hdr.qdcount--)
unpack_query(&p, &q);
for(; hdr.ancount; hdr.ancount--) {
unpack_rr(&p, &rr);
if (rr.rr_class != C_IN)
continue;
switch (rr.rr_type) {
case T_CNAME:
if (action == ASR_GETHOSTBYNAME)
r = hostent_add_alias(h, rr.rr_dname, 1);
else
r = hostent_set_cname(h, rr.rr_dname, 1);
break;
case T_PTR:
if (action != ASR_GETHOSTBYADDR)
continue;
r = hostent_set_cname(h, rr.rr.ptr.ptrname, 1);
/* XXX See if we need MULTI_PTRS_ARE_ALIASES */
break;
case T_A:
if (h->h_addrtype != AF_INET)
break;
r = hostent_set_cname(h, rr.rr_dname, 1);
r = hostent_add_addr(h, &rr.rr.in_a.addr, 4);
break;
case T_AAAA:
if (h->h_addrtype != AF_INET6)
break;
r = hostent_set_cname(h, rr.rr_dname, 1);
r = hostent_add_addr(h, &rr.rr.in_aaaa.addr6, 16);
break;
}
}
return (0);
}
/*
* Fill the hostent from the given DNS packet.
*/
static struct hostent *
hostent_from_packet(int reqtype, int family, char *pkt, size_t pktlen)
{
struct hostent *h;
struct packed p;
struct header hdr;
struct query q;
struct rr rr;
if ((h = hostent_alloc(family)) == NULL)
return (NULL);
packed_init(&p, pkt, pktlen);
unpack_header(&p, &hdr);
for(; hdr.qdcount; hdr.qdcount--)
unpack_query(&p, &q);
for(; hdr.ancount; hdr.ancount--) {
unpack_rr(&p, &rr);
if (rr.rr_class != C_IN)
continue;
switch (rr.rr_type) {
case T_CNAME:
if (reqtype == ASR_GETHOSTBYNAME) {
if (hostent_add_alias(h, rr.rr_dname, 1) == -1)
goto fail;
} else {
if (hostent_set_cname(h, rr.rr_dname, 1) == -1)
goto fail;
}
break;
case T_PTR:
if (reqtype != ASR_GETHOSTBYADDR)
break;
if (hostent_set_cname(h, rr.rr.ptr.ptrname, 1) == -1)
goto fail;
/* XXX See if we need MULTI_PTRS_ARE_ALIASES */
break;
case T_A:
if (reqtype != ASR_GETHOSTBYNAME)
break;
if (family != AF_INET)
break;
if (hostent_set_cname(h, rr.rr_dname, 1) == -1)
goto fail;
if (hostent_add_addr(h, &rr.rr.in_a.addr, 4) == -1)
goto fail;
break;
case T_AAAA:
if (reqtype != ASR_GETHOSTBYNAME)
break;
if (family != AF_INET6)
break;
if (hostent_set_cname(h, rr.rr_dname, 1) == -1)
goto fail;
if (hostent_add_addr(h, &rr.rr.in_aaaa.addr6, 16) == -1)
goto fail;
break;
}
}
return (h);
fail:
free(h);
return (NULL);
}
