From: Heiko Hund <he...@ist.eigentlich.net> The script didn't handle scenarios well where two or more parallel VPN connections want to replace the default DNS server. The DNS configuration has a chance to get broken by the connections going down in a different order than they came up in.
Disallowing all but the first connection to modify the default DNS server will effectively prevent this issue. While it may break DNS for the latter connections, it is the best we can do without knowing specifics about the configurations. Change-Id: I7b413578a8fc0c65fca26f72b901a9f7bc34b137 Signed-off-by: Heiko Hund <he...@ist.eigentlich.net> Acked-by: Arne Schwabe <arne-open...@rfc2549.org> --- This change was reviewed on Gerrit and approved by at least one developer. I request to merge it to master. Gerrit URL: https://gerrit.openvpn.net/c/openvpn/+/1066 This mail reflects revision 2 of this Change. Acked-by according to Gerrit (reflected above): Arne Schwabe <arne-open...@rfc2549.org> diff --git a/distro/dns-scripts/macos-dns-updown.sh b/distro/dns-scripts/macos-dns-updown.sh index 89d6882..c15abaa 100644 --- a/distro/dns-scripts/macos-dns-updown.sh +++ b/distro/dns-scripts/macos-dns-updown.sh @@ -30,6 +30,7 @@ itf_dns_key="State:/Network/Service/openvpn-${dev}/DNS" dns_backup_key="State:/Network/Service/openvpn-${dev}/DnsBackup" +dns_backup_key_pattern="State:/Network/Service/openvpn-.*/DnsBackup" function primary_dns_key { local uuid=$(echo "show State:/Network/Global/IPv4" | /usr/sbin/scutil | grep "PrimaryService" | cut -d: -f2 | xargs) @@ -166,6 +167,11 @@ echo -e "${cmds}" | /usr/sbin/scutil set_search_domains "$search_domains" else + echo list ${dns_backup_key_pattern} | /usr/sbin/scutil | grep -q 'no key' || { + echo "setting DNS failed, already redirecting to another tunnel" + exit 1 + } + local cmds="" cmds+="get $(primary_dns_key)\n" cmds+="set ${dns_backup_key}\n" @@ -200,6 +206,9 @@ echo "remove ${itf_dns_key}" | /usr/sbin/scutil unset_search_domains "$search_domains" else + # Do not unset if this tunnel did not set/backup DNS before + echo list ${dns_backup_key} | /usr/sbin/scutil | grep -qv 'no key' || return + local cmds="" cmds+="get ${dns_backup_key}\n" cmds+="set $(primary_dns_key)\n" _______________________________________________ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel
