factor/extra/dns/forwarding/forwarding.factor

103 lines
2.7 KiB
Factor

USING: kernel sequences combinators accessors locals random
combinators.short-circuit
io.sockets
dns dns.util dns.cache.rr dns.cache.nx ;
IN: dns.forwarding
! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
: forever ( quot -- ) [ call ] [ forever ] bi ; inline recursive
! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
:: query->rrs ( QUERY -- rrs/f )
[let | RRS [ QUERY cache-get ] |
RRS
[ RRS ]
[
[let | NAME [ QUERY name>> ]
TYPE [ QUERY type>> ]
CLASS [ QUERY class>> ] |
[let | RRS/CNAME [ T{ query f NAME CNAME CLASS } cache-get ] |
RRS/CNAME f =
[ f ]
[
[let | RR/CNAME [ RRS/CNAME first ] |
[let | REAL-NAME [ RR/CNAME rdata>> ] |
[let | RRS [
T{ query f REAL-NAME TYPE CLASS } query->rrs
] |
RRS
[ RRS/CNAME RRS append ]
[ f ]
if
] ] ]
]
if
] ]
]
if
] ;
:: answer-from-cache ( MSG -- msg/f )
[let | QUERY [ MSG message-query ] |
[let | NX [ QUERY name>> non-existent-name? ]
RRS [ QUERY query->rrs ] |
{
{ [ NX ] [ MSG NAME-ERROR >>rcode ] }
{ [ RRS ] [ MSG RRS >>answer-section ] }
{ [ t ] [ f ] }
}
cond
]
] ;
! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
: message-soa ( message -- rr/soa )
authority-section>> [ type>> SOA = ] filter first ;
:: cache-message ( MSG -- msg )
MSG rcode>> NAME-ERROR =
[
[let | NAME [ MSG message-query name>> ]
TTL [ MSG message-soa ttl>> ] |
NAME TTL cache-non-existent-name
]
]
when
MSG answer-section>> [ cache-add ] each
MSG authority-section>> [ cache-add ] each
MSG additional-section>> [ cache-add ] each
MSG ;
: answer-from-server ( msg servers -- msg ) random ask-server cache-message ;
:: find-answer ( MSG SERVERS -- msg )
{ [ MSG answer-from-cache ] [ MSG SERVERS answer-from-server ] } 0|| ;
! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
:: start-server ( ADDR-SPEC SERVERS -- )
[let | SOCKET [ ADDR-SPEC <datagram> ] |
[
SOCKET receive-packet
[ parse-message SERVERS find-answer message->ba ]
change-data
respond
]
forever
] ;