Add dns.server

extra/dns/server/server.factor

@@ -0,0 +1,139 @@
+
+USING: kernel
+       combinators
+       sequences
+       math
+       io.sockets
+       unicode.case
+       accessors
+       combinators.cleave
+       newfx
+       dns ;
+
+IN: dns.server
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: records ( -- vector ) V{ } ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: filter-by-name ( records name -- records ) swap [ name>> = ] with filter ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: {name-type-class} ( obj -- array )
+  { [ name>> >lower ] [ type>> ] [ class>> ] } <arr> ;
+
+: rr=query? ( obj obj -- ? ) [ {name-type-class} ] bi@ = ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: matching-rrs  ( query -- rrs ) records [ rr=query? ] with filter ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: matching-rrs? ( query -- query rrs/f ? ) dup matching-rrs dup empty? not ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: matching-cname? ( query -- query rr/f ? )
+  dup clone CNAME >>type matching-rrs
+  dup empty? [ drop f f ] [ 1st t ] if ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+DEFER: query->rrs
+
+: query-canonical ( query rr -- rrs )
+  tuck [ clone ] [ rdata>> ] bi* >>name query->rrs prefix-on ;
+
+: query->rrs ( query -- rrs/f )
+    {
+      { [      matching-rrs?   ] [ nip ] }
+      { [ drop matching-cname? ] [ query-canonical ] }
+      { [ drop t               ] [ drop f ] }
+    }
+  cond ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: cdr-name ( name -- name ) dup CHAR: . index 1+ tail ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: delegate-servers? ( name -- name rrs ? )
+  dup NS IN query boa matching-rrs dup empty? not ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: delegate-servers ( name -- rrs )
+    {
+      { [ dup "" = ]          [ drop { } ] }
+      { [ delegate-servers? ] [ nip ] }
+      { [ drop t ]            [ cdr-name delegate-servers ] }
+    }
+  cond ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: delegate-addresses ( rrs-ns -- rrs-a )
+  [ rdata>> A IN query boa matching-rrs ] map concat ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: have-delegates? ( query -- query rrs-ns ? )
+  dup name>> delegate-servers dup empty? not ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: fill-additional ( message -- message )
+  dup authority-section>> delegate-addresses >>additional-section ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: no-records-with-name? ( query -- query ? )
+  dup name>> records [ name>> = ] with filter empty? ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: find-answer ( message -- message )
+  dup message-query                     ! message query
+    {
+      { [ dup query->rrs dup   ] [ nip >>answer-section 1 >>aa ] }
+      { [ drop have-delegates? ] [ nip >>authority-section fill-additional ] }
+      { [ drop no-records-with-name? ] [ drop NAME-ERROR >>rcode ] }
+      { [ drop t ] [ ] }
+    }
+  cond ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: (socket) ( -- vec ) V{ f } ;
+
+: socket ( -- socket ) (socket) 1st ;
+
+: init-socket-on-port ( port -- )
+  f swap <inet4> <datagram> 0 (socket) as-mutate ;
+
+: init-socket ( -- ) 53 init-socket-on-port ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: loop ( -- )
+  socket receive
+  swap
+  parse-message
+  find-answer
+  message->ba
+  swap
+  socket send
+  loop ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+: start ( -- ) init-socket loop ;
+
+! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+
+MAIN: start