From a31ddef36df7970db1145f7ae66060f8e3eebf3f Mon Sep 17 00:00:00 2001 From: Robert Greenwalt Date: Thu, 22 Aug 2013 16:56:48 -0700 Subject: [PATCH] Change how DNS resolver handle no default iface We used to just try any iface we'd been told about as a fallback, but that will end up mistakenly using a secondary network's dns when we really don't have a default connection. It also messed up our detection of whether we were doing the lookup on the default or not (we'd get back our secondary net iface as the default, do the compare and think we were on default). Remove the lies and let dns fail if we don't have an iface for it. bug:10132565 Change-Id: I5f0f2abacaaaaf23c5292b20fba9d8dcb6fb10c5 --- libc/netbsd/net/getaddrinfo.c | 6 +++--- libc/netbsd/resolv/res_cache.c | 16 +++++++--------- 2 files changed, 10 insertions(+), 12 deletions(-) diff --git a/libc/netbsd/net/getaddrinfo.c b/libc/netbsd/net/getaddrinfo.c index c4766e406..0d1949d15 100644 --- a/libc/netbsd/net/getaddrinfo.c +++ b/libc/netbsd/net/getaddrinfo.c @@ -1874,10 +1874,10 @@ static bool _using_default_dns(const char *iface) if (iface == NULL || *iface == '\0') return true; if_len = _resolv_get_default_iface(buf, sizeof(buf)); - if (if_len + 1 <= sizeof(buf)) { - if (strcmp(buf, iface) != 0) return false; + if (if_len != 0 && if_len + 1 <= sizeof(buf)) { + if (strcmp(buf, iface) == 0) return true; } - return true; + return false; } /*ARGSUSED*/ diff --git a/libc/netbsd/resolv/res_cache.c b/libc/netbsd/resolv/res_cache.c index 829bf1032..7e367adce 100644 --- a/libc/netbsd/resolv/res_cache.c +++ b/libc/netbsd/resolv/res_cache.c @@ -2426,18 +2426,16 @@ _resolv_get_default_iface(char* buff, int buffLen) ifname = _get_default_iface_locked(); // never null, but may be empty - // if default interface not set. Get first cache with an interface + // if default interface not set give up. if (ifname[0] == '\0') { - ifname = _find_any_iface_name_locked(); // may be null + pthread_mutex_unlock(&_res_cache_list_lock); + return 0; } - // if we got the default iface or if (no-default) the find_any call gave an answer - if (ifname) { - len = strlen(ifname); - if (len < buffLen) { - strncpy(buff, ifname, len); - buff[len] = '\0'; - } + len = strlen(ifname); + if (len < buffLen) { + strncpy(buff, ifname, len); + buff[len] = '\0'; } else { buff[0] = '\0'; }