RAHHH

backend/lib/python3.12/site-packages/twisted/names/tap.py

@@ -0,0 +1,149 @@
+# -*- test-case-name: twisted.names.test.test_tap -*-
+# Copyright (c) Twisted Matrix Laboratories.
+# See LICENSE for details.
+
+"""
+Domain Name Server
+"""
+
+import os
+import traceback
+
+from twisted.application import internet, service
+from twisted.names import authority, dns, secondary, server
+from twisted.python import usage
+
+
+class Options(usage.Options):
+    optParameters = [
+        ["interface", "i", "", "The interface to which to bind"],
+        ["port", "p", "53", "The port on which to listen"],
+        [
+            "resolv-conf",
+            None,
+            None,
+            "Override location of resolv.conf (implies --recursive)",
+        ],
+        ["hosts-file", None, None, "Perform lookups with a hosts file"],
+    ]
+
+    optFlags = [
+        ["cache", "c", "Enable record caching"],
+        ["recursive", "r", "Perform recursive lookups"],
+        ["verbose", "v", "Log verbosely"],
+    ]
+
+    compData = usage.Completions(
+        optActions={"interface": usage.CompleteNetInterfaces()}
+    )
+
+    zones = None
+    zonefiles = None
+
+    def __init__(self):
+        usage.Options.__init__(self)
+        self["verbose"] = 0
+        self.bindfiles = []
+        self.zonefiles = []
+        self.secondaries = []
+
+    def opt_pyzone(self, filename):
+        """Specify the filename of a Python syntax zone definition"""
+        if not os.path.exists(filename):
+            raise usage.UsageError(filename + ": No such file")
+        self.zonefiles.append(filename)
+
+    def opt_bindzone(self, filename):
+        """Specify the filename of a BIND9 syntax zone definition"""
+        if not os.path.exists(filename):
+            raise usage.UsageError(filename + ": No such file")
+        self.bindfiles.append(filename)
+
+    def opt_secondary(self, ip_domain):
+        """Act as secondary for the specified domain, performing
+        zone transfers from the specified IP (IP/domain)
+        """
+        args = ip_domain.split("/", 1)
+        if len(args) != 2:
+            raise usage.UsageError("Argument must be of the form IP[:port]/domain")
+        address = args[0].split(":")
+        if len(address) == 1:
+            address = (address[0], dns.PORT)
+        else:
+            try:
+                port = int(address[1])
+            except ValueError:
+                raise usage.UsageError(
+                    f"Specify an integer port number, not {address[1]!r}"
+                )
+            address = (address[0], port)
+        self.secondaries.append((address, [args[1]]))
+
+    def opt_verbose(self):
+        """Increment verbosity level"""
+        self["verbose"] += 1
+
+    def postOptions(self):
+        if self["resolv-conf"]:
+            self["recursive"] = True
+
+        self.svcs = []
+        self.zones = []
+        for f in self.zonefiles:
+            try:
+                self.zones.append(authority.PySourceAuthority(f))
+            except Exception:
+                traceback.print_exc()
+                raise usage.UsageError("Invalid syntax in " + f)
+        for f in self.bindfiles:
+            try:
+                self.zones.append(authority.BindAuthority(f))
+            except Exception:
+                traceback.print_exc()
+                raise usage.UsageError("Invalid syntax in " + f)
+        for f in self.secondaries:
+            svc = secondary.SecondaryAuthorityService.fromServerAddressAndDomains(*f)
+            self.svcs.append(svc)
+            self.zones.append(self.svcs[-1].getAuthority())
+        try:
+            self["port"] = int(self["port"])
+        except ValueError:
+            raise usage.UsageError("Invalid port: {!r}".format(self["port"]))
+
+
+def _buildResolvers(config):
+    """
+    Build DNS resolver instances in an order which leaves recursive
+    resolving as a last resort.
+
+    @type config: L{Options} instance
+    @param config: Parsed command-line configuration
+
+    @return: Two-item tuple of a list of cache resovers and a list of client
+        resolvers
+    """
+    from twisted.names import cache, client, hosts
+
+    ca, cl = [], []
+    if config["cache"]:
+        ca.append(cache.CacheResolver(verbose=config["verbose"]))
+    if config["hosts-file"]:
+        cl.append(hosts.Resolver(file=config["hosts-file"]))
+    if config["recursive"]:
+        cl.append(client.createResolver(resolvconf=config["resolv-conf"]))
+    return ca, cl
+
+
+def makeService(config):
+    ca, cl = _buildResolvers(config)
+
+    f = server.DNSServerFactory(config.zones, ca, cl, config["verbose"])
+    p = dns.DNSDatagramProtocol(f)
+    f.noisy = 0
+    ret = service.MultiService()
+    for klass, arg in [(internet.TCPServer, f), (internet.UDPServer, p)]:
+        s = klass(config["port"], arg, interface=config["interface"])
+        s.setServiceParent(ret)
+    for svc in config.svcs:
+        svc.setServiceParent(ret)
+    return ret