Files
zonemaster.es/zonemaster-ldns/ldns/lua/echo.lua
Malin eaaa8f6a11 fix: populate ldns submodule and add autotools to LDNS build stage
- Re-cloned zonemaster-ldns with --recurse-submodules so the bundled
  ldns C library source (including Changelog and configure.ac) is present
- Added autoconf, automake, libtool to Dockerfile.backend ldns-build stage
  so libtoolize + autoreconf can generate ldns/configure during make

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-04-21 08:33:38 +02:00

69 lines
1.7 KiB
Lua

-- source the lib file with the function
dofile("rns-lib.lua")
-- echo whatever is received
-- this function disfigures the packet
function lua_packet_mangle(orig_packet)
-- Dont do anything just mirror
-- local rr1 = record.new_frm_str("www.miek.nl IN A 127.0.0.1")
-- packet.push_rr(orig_packet, LDNS_SECTION_ANSWER, rr1)
return(packet.to_buf(orig_packet))
end
rdf_ip = rdf.new_frm_str(LDNS_RDF_TYPE_A, "127.0.0.1")
socket = udp.server_open(rdf_ip, 5353)
if socket == nil then
os.exit(EXIT_FAILURE)
end
rdf_ip_nameserver = rdf.new_frm_str(LDNS_RDF_TYPE_A, "213.154.224.39")
while true do
-- read from the socket, this blocks...
wirebuf, sockaddr_from = udp.read(socket)
-- wrap this in new functions
if wirebuf == nil then
lua_debug("nothing received")
else
-- somebody is writing
wirepkt = buffer.to_pkt(wirebuf)
packet.print(wirepkt)
wirebuf2 = packet.to_buf(wirepkt)
-- send it to /our/ nameserver
socket_nameserver = udp.open(rdf_ip_nameserver, 53)
if socket_nameserver == nil then
os.exit(EXIT_FAILURE)
end
nameserver_bytes = udp.write(socket_nameserver, wirebuf2, rdf_ip_nameserver, 53)
if nameserver_bytes == nil then
lua_debug("ns write error")
end
nameserver_buf, sockaddr_from_nameserver = udp.read(socket_nameserver)
udp.close(socket_nameserver)
nameserver_pkt = buffer.to_pkt(nameserver_buf)
packet.print(nameserver_pkt)
-- make a new buf and write that back to the client
nsbuf2 = lua_packet_mangle(nameserver_pkt)
bytes = lua_udp_write(socket, nsbuf2, sockaddr_from) --this works
if bytes == nil then
lua_debug("write error")
end
buffer.free(nsbuf2)
buffer.free(nameserver_buf)
buffer.free(wirebuf2)
buffer.free(wirebuf)
end
end
udp.close(socket)