diff options
Diffstat (limited to 'resolv')
| -rw-r--r-- | resolv/res_init.c | 9 | ||||
| -rw-r--r-- | resolv/res_send.c | 15 | ||||
| -rw-r--r-- | resolv/resolv.h | 6 |
3 files changed, 19 insertions, 11 deletions
diff --git a/resolv/res_init.c b/resolv/res_init.c index 640e087920..d1a5681a93 100644 --- a/resolv/res_init.c +++ b/resolv/res_init.c @@ -241,8 +241,8 @@ __res_vinit(res_state statp, int preinit) { line[sizeof(name) - 1] == '\t')) if ((fp = fopen(_PATH_RESCONF, "rc")) != NULL) { - /* No threads use this stream. */ - __fsetlocking (fp, FSETLOCKING_BYCALLER); + /* No threads use this stream. */ + __fsetlocking (fp, FSETLOCKING_BYCALLER); /* read the config file */ while (fgets_unlocked(buf, sizeof(buf), fp) != NULL) { /* skip comments */ @@ -397,8 +397,11 @@ __res_vinit(res_state statp, int preinit) { if (nserv > 1) statp->nscount = nserv; #ifdef _LIBC - if (nservall - nserv > 0) + if (nservall - nserv > 0) { statp->_u._ext.nscount6 = nservall - nserv; + /* We try IPv6 servers again. */ + statp->ipv6_unavail = false; + } #endif #ifdef RESOLVSORT statp->nsort = nsort; diff --git a/resolv/res_send.c b/resolv/res_send.c index f38c399ffd..27dd1d4351 100644 --- a/resolv/res_send.c +++ b/resolv/res_send.c @@ -813,17 +813,20 @@ send_dg(res_state statp, struct pollfd pfd[1]; int ptimeout; struct sockaddr_in6 from; - static int socket_pf = 0; socklen_t fromlen; int resplen, seconds, n; if (EXT(statp).nssocks[ns] == -1) { /* only try IPv6 if IPv6 NS and if not failed before */ - if ((EXT(statp).nscount6 > 0) && (socket_pf != PF_INET)) { + if ((EXT(statp).nscount6 > 0) && !statp->ipv6_unavail) { EXT(statp).nssocks[ns] = socket(PF_INET6, SOCK_DGRAM, 0); - socket_pf = EXT(statp).nssocks[ns] < 0 ? PF_INET - : PF_INET6; + if (EXT(statp).nssocks[ns] < 0) + statp->ipv6_unavail = errno == EAFNOSUPPORT; + /* If IPv6 socket and nsap is IPv4, make it + IPv4-mapped */ + else if (nsap->sin6_family == AF_INET) + convaddr4to6(nsap); } if (EXT(statp).nssocks[ns] < 0) EXT(statp).nssocks[ns] = socket(PF_INET, SOCK_DGRAM, 0); @@ -832,9 +835,7 @@ send_dg(res_state statp, Perror(statp, stderr, "socket(dg)", errno); return (-1); } - /* If IPv6 socket and nsap is IPv4, make it IPv4-mapped */ - if ((socket_pf == PF_INET6) && (nsap->sin6_family == AF_INET)) - convaddr4to6(nsap); + /* * On a 4.3BSD+ machine (client and server, * actually), sending to a nameserver datagram diff --git a/resolv/resolv.h b/resolv/resolv.h index 9aa09b8701..105631ee7d 100644 --- a/resolv/resolv.h +++ b/resolv/resolv.h @@ -110,21 +110,25 @@ struct __res_state { nsaddr_list[MAXNS]; /* address of name server */ # define nsaddr nsaddr_list[0] /* for backward compatibility */ u_short id; /* current message id */ + /* 2 byte hole here. */ char *dnsrch[MAXDNSRCH+1]; /* components of domain to search */ char defdname[256]; /* default domain (deprecated) */ u_long pfcode; /* RES_PRF_ flags - see below. */ unsigned ndots:4; /* threshold for initial abs. query */ unsigned nsort:4; /* number of elements in sort_list[] */ - char unused[3]; + unsigned ipv6_unavail:1; /* connecting to IPv6 server failed */ + unsigned unused:23; struct { struct in_addr addr; u_int32_t mask; } sort_list[MAXRESOLVSORT]; + /* 4 byte hole here on 64-bit architectures. */ res_send_qhook qhook; /* query hook */ res_send_rhook rhook; /* response hook */ int res_h_errno; /* last one set for this context */ int _vcsock; /* PRIVATE: for res_send VC i/o */ u_int _flags; /* PRIVATE: see below */ + /* 4 byte hole here on 64-bit architectures. */ union { char pad[52]; /* On an i386 this means 512b total. */ struct { |