diff options
| -rw-r--r-- | src/network/__dns.c | 36 |
1 files changed, 31 insertions, 5 deletions
diff --git a/src/network/__dns.c b/src/network/__dns.c index 8f3c6370..97d8031c 100644 --- a/src/network/__dns.c +++ b/src/network/__dns.c @@ -11,6 +11,7 @@ #include <ctype.h> #include <unistd.h> #include <pthread.h> +#include <errno.h> #include "__dns.h" #include "stdio_impl.h" @@ -35,9 +36,9 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt) 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; @@ -75,10 +76,12 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt) 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) { @@ -93,6 +96,29 @@ int __dns_doqueries(unsigned char *dest, const char *name, int *rr, int rrcnt) 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); |