NAME

       dqcache - DNS cache with DNSCurve support

DESCRIPTION

       dqcache is recursive DNS server derived from dnscache (https://cr.yp.to/djbdns/dnscache.html)

CONFIGURATION

       dqcache runs chrooted in the directory specified by the $ROOT environment variable, under the uid and gid
       specified by the $UID and $GID environment variables.

       dqcache listens for incoming UDP packets and TCP connections addressed to port 53 of $IP.  Typically  $IP
       is 127.0.0.1, but it can also be an externally accessible IP address.

       dqcache  accepts  connections  from localhost (127.0.0.0/8 or ::1/128).  For external connections dqcache
       has file-style accesslist.
           e.g. for IPv4 address 1.2.3.4 dqcache allows connection when sees a file named:
           ip4/1.2.3.4 or
           ip4/1.2.3 or
           ip4/1.2 or
           ip4/1
           e.g. for IPv6 address 2a02:598:7000:101:12dd:b1ff:fede:3476 dqcache allows connection when sees a file named:
           ip6/2a02:598:7000:101:12dd:b1ff:fede:3476 or
           ip6/2a02:598:7000:101:12dd:b1ff:fede or
           ip6/2a02:598:7000:101:12dd:b1ff or
           ip6/2a02:598:7000:101:12dd or
           ip6/2a02:598:7000:101 or
           ip6/2a02:598:7000 or
           ip6/2a02:598 or
           ip6/2a02
       when environment variable $OKCLIENT is set, dqcache accepts all connections.

       Warning , dqcache encrypts DNS packets and should run on client's machine. If You run dqcache on external
       IP (not on localhost), You're probably doing it wrong.

       dqcache  sends  outgoing IPv4 packets from high ports of $IPSEND4. Typically $IPSEND4 is 0.0.0.0, meaning
       the machine's primary IPv4 address.

       dqcache sends outgoing IPv6 packets from high ports of $IPSEND6. Typically $IPSEND6 is  ::,  meaning  the
       machine's primary IPv6 address.

       If $HIDETTL is set, dqcache always uses a TTL of 0 in its responses

       dqcache  reads  a list of root servers as an anchor, one record per line, from servers/@.  The record has
       format {IP} or {IP}|{DNSCURVEPUBLICKEY} e.g.:
           servers/@:
           198.41.0.4
           2001:503:ba3e::2:30
           192.228.79.201
           2001:500:84::b
           etc.

       dqcache also scans the servers directory for anchors for other domains, one record per line.  The  record
       has format {IP} or {IP}|{DNSCURVEPUBLICKEY} e.g.:
            servers/dnscurve.cz:
            185.66.36.55|uz5mj60yr9tnudkkpcglw1y0w6dlh78j1l4gk4z7t8bsf1u4d48wlq
            37.157.196.86|uz5mj60yr9tnudkkpcglw1y0w6dlh78j1l4gk4z7t8bsf1u4d48wlq
            2a02:2b88:2:1::127d:1|uz5mj60yr9tnudkkpcglw1y0w6dlh78j1l4gk4z7t8bsf1u4d48wlq
            2a03:1e20:0:5::2|uz5mj60yr9tnudkkpcglw1y0w6dlh78j1l4gk4z7t8bsf1u4d48wlq

       dqcache  supports  forward-only  mode.  If  $FORWARDONLY is set, dqcache treats servers/@ as a list of IP
       addresses for other caches, not root servers. It forwards queries to those caches the  same  way  that  a
       client does, rather than contacting a chain of servers according to NS records.

       dqcache  uses  a  fixed-size  cache,  as  controlled  by  the  $CACHESIZE environment variable. Typically
       $CACHESIZE is 10000000 (10MB).

       dqcache typically generates new secret key at start of program. If  environment  variable  $SECRETKEY  is
       set, then dqcache loads this secret key. $SECRETKEY must be safely generated using dqcache-makekey(1).

       Note  that  dqcache uses internally two secret keys, one used as the discrete logarithm of the public key
       (256bit DNSCurve key) and one to encrypt the nonce (128bit TEA symmetric key). Both  of  these  keys  are
       actually derived from $SECRETKEY using crypto_stream_salsa20().

       dqcache  also  supports  nonce-separation  via  environment variable $NONCESTART. This means that several
       caches share a key but use separate nonces:
         e.g.:
         NONCESTART=100 ... the first of four caches is configured to use top bits 100
         NONCESTART=101 ... the second is configured to use top bits 101
         NONCESTART=110 ... the third is configured to use top bits 110
         NONCESTART=111 ... and the fourth is configured to use top bits 111.
         etc.

       dqcache typically supports DNSCurve in 'combined mode' (meaning:  if  Streamlined  query  fails,  dqcache
       tries also TXT query).  Environment variable $DNSCURVETYPE selects specific DNSCurve type.
         DNSCURVETYPE=1 ... Streamlined only DNSCurve
         DNSCURVETYPE=2 ... TXT only DNSCurve

       dqcache  caches  records  for at least $MINTTL seconds, when MINTTL is set. It's limited <0-300> seconds.
       Use only if you really know what you're doing.

       dqcache sends only IPv4 queries, when DISABLEIPV6 is set.  Use only if you really know what you're doing.

SEE ALSO

       dqcache-makekey(1), dq(1), dnscache(8)

       https://mojzis.com/software/dq
       https://dnscurve.org/
       https://cr.yp.to/djbdns/dnscache.html

                                                                                                      dqcache(8)