commit df43691bedae4e5024aa39d6b10d47b99dc946e4 Author: Arturo Filastò <art@fuffa.org> Date: Wed Jun 25 15:43:28 2014 +0200 Add test helper that can be used to discover the resolver being used by a probe. --- oonib.conf.example | 6 ++++++ oonib/oonibackend.py | 37 +++++++++++++++++++++++++------------ oonib/testhelpers/dns_helpers.py | 29 ++++++++++++++++++++++++++++- 3 files changed, 59 insertions(+), 13 deletions(-) diff --git a/oonib.conf.example b/oonib.conf.example index c25d405..6b07414 100644 --- a/oonib.conf.example +++ b/oonib.conf.example @@ -52,6 +52,12 @@ helpers: tcp_port: 57005 resolver_address: '8.8.8.8:53' + dns_discovery: + address: null + udp_port: 53 + tcp_port: 53 + resolver_address: null + ssl: address: null private_key: 'private.key' diff --git a/oonib/oonibackend.py b/oonib/oonibackend.py index 3e6598c..2a9fa7d 100644 --- a/oonib/oonibackend.py +++ b/oonib/oonibackend.py @@ -10,13 +10,9 @@ from twisted.application import internet, service from twisted.names import dns -from cyclone import web - from oonib.testhelpers import dns_helpers, ssl_helpers from oonib.testhelpers import http_helpers, tcp_helpers -from oonib import log - from oonib.config import config if config.main.uid and config.main.gid: @@ -30,42 +26,59 @@ serviceCollection = service.IServiceCollection(application) if config.helpers['ssl'].port: print "Starting SSL helper on %s" % config.helpers['ssl'].port ssl_helper = internet.SSLServer(int(config.helpers['ssl'].port), - http_helpers.HTTPReturnJSONHeadersHelper(), - ssl_helpers.SSLContext(config)) + http_helpers.HTTPReturnJSONHeadersHelper(), + ssl_helpers.SSLContext(config)) ssl_helper.setServiceParent(serviceCollection) # Start the DNS Server related services if config.helpers['dns'].tcp_port: print "Starting TCP DNS Helper on %s" % config.helpers['dns'].tcp_port tcp_dns_helper = internet.TCPServer(int(config.helpers['dns'].tcp_port), - dns_helpers.DNSTestHelper()) + dns_helpers.DNSTestHelper()) tcp_dns_helper.setServiceParent(serviceCollection) if config.helpers['dns'].udp_port: print "Starting UDP DNS Helper on %s" % config.helpers['dns'].udp_port udp_dns_factory = dns.DNSDatagramProtocol(dns_helpers.DNSTestHelper()) udp_dns_helper = internet.UDPServer(int(config.helpers['dns'].udp_port), - udp_dns_factory) + udp_dns_factory) udp_dns_helper.setServiceParent(serviceCollection) +if config.helpers['dns_discovery'].udp_port: + print ("Starting UDP DNS Discovery Helper on %s" % + config.helpers['dns_discovery'].udp_port) + udp_dns_discovery = internet.UDPServer(int(config.helpers['dns_discovery'].udp_port), + dns.DNSDatagramProtocol( + dns_helpers.DNSResolverDiscovery() + )) + udp_dns_discovery.setServiceParent(serviceCollection) + +if config.helpers['dns_discovery'].tcp_port: + print ("Starting TCP DNS Discovery Helper on %s" % + config.helpers['dns_discovery'].tcp_port) + tcp_dns_discovery = internet.TCPServer(int(config.helpers['dns_discovery'].tcp_port), + dns_helpers.DNSResolverDiscovery()) + tcp_dns_discovery.setServiceParent(serviceCollection) + + # XXX this needs to be ported # Start the OONI daphn3 backend if config.helpers['daphn3'].port: print "Starting Daphn3 helper on %s" % config.helpers['daphn3'].port daphn3_helper = internet.TCPServer(int(config.helpers['daphn3'].port), - tcp_helpers.Daphn3Server()) + tcp_helpers.Daphn3Server()) daphn3_helper.setServiceParent(serviceCollection) if config.helpers['tcp-echo'].port: print "Starting TCP echo helper on %s" % config.helpers['tcp-echo'].port tcp_echo_helper = internet.TCPServer(int(config.helpers['tcp-echo'].port), - tcp_helpers.TCPEchoHelper()) + tcp_helpers.TCPEchoHelper()) tcp_echo_helper.setServiceParent(serviceCollection) if config.helpers['http-return-json-headers'].port: print "Starting HTTP return request helper on %s" % config.helpers['http-return-json-headers'].port http_return_request_helper = internet.TCPServer( - int(config.helpers['http-return-json-headers'].port), - http_helpers.HTTPReturnJSONHeadersHelper()) + int(config.helpers['http-return-json-headers'].port), + http_helpers.HTTPReturnJSONHeadersHelper()) http_return_request_helper.setServiceParent(serviceCollection) diff --git a/oonib/testhelpers/dns_helpers.py b/oonib/testhelpers/dns_helpers.py index fbf932b..ff31dde 100644 --- a/oonib/testhelpers/dns_helpers.py +++ b/oonib/testhelpers/dns_helpers.py @@ -1,4 +1,4 @@ -from twisted.names import client, server +from twisted.names import client, server, dns from oonib.config import config @@ -21,3 +21,30 @@ class DNSTestHelper(server.DNSServerFactory): def handleQuery(self, message, protocol, address): server.DNSServerFactory.handleQuery(self, message, protocol, address) + + +class DNSResolverDiscovery(server.DNSServerFactory): + """ + This test helper is used to discover the IP address of the resolver being + used by a ooniprobe client. + To use it you should set it up on a machine that has been delegated as the + authoritative name server for a specific subdomain. + You can do so by adding the following to your zone file: + + mysubdomain IN NS ns.mysubdomain.example.org. + ns.mysubdomain.example.org IN A 10.42.42.42 + + Replace 10.42.42.42 with the IP address of the machine running oonib. + + You will then be able to perform A lookups on subdomains of + mysubdomain.example.org and retrieve in the query answer section the IP + address of the resolver that was used for performing the request. + """ + def handleQuery(self, message, protocol, address): + query = message.queries[0] + if query.type == dns.A: + ans = dns.RRHeader(bytes(query.name), + payload=dns.Record_A(bytes(address[0]), 0)) + message.answers = [ans] + message.answer = 1 + self.sendReply(protocol, message, address)