1# SPDX-License-Identifier: GPL-2.0-only 2# 3# Configuration for DNS Resolver 4# 5config DNS_RESOLVER 6 tristate "DNS Resolver support" 7 depends on NET && KEYS 8 help 9 Saying Y here will include support for the DNS Resolver key type 10 which can be used to make upcalls to perform DNS lookups in 11 userspace. 12 13 DNS Resolver is used to query DNS server for information. Examples 14 being resolving a UNC hostname element to an IP address for CIFS or 15 performing a DNS query for AFSDB records so that AFS can locate a 16 cell's volume location database servers. 17 18 DNS Resolver is used by the CIFS and AFS modules, and would support 19 SMB2 later. DNS Resolver is supported by the userspace upcall 20 helper "/sbin/dns.resolver" via /etc/request-key.conf. 21 22 See <file:Documentation/networking/dns_resolver.rst> for further 23 information. 24 25 To compile this as a module, choose M here: the module will be called 26 dnsresolver. 27 28 If unsure, say N. 29