Ausgabe der neuen DB Einträge

venv/lib/python3.9/site-packages/twisted/names/hosts.py

@@ -0,0 +1,153 @@
+# -*- test-case-name: twisted.names.test.test_hosts -*-
+# Copyright (c) Twisted Matrix Laboratories.
+# See LICENSE for details.
+
+"""
+hosts(5) support.
+"""
+
+from __future__ import division, absolute_import
+
+from twisted.python.compat import nativeString
+from twisted.names import dns
+from twisted.python import failure
+from twisted.python.filepath import FilePath
+from twisted.internet import defer
+from twisted.internet.abstract import isIPAddress
+
+from twisted.names import common
+
+def searchFileForAll(hostsFile, name):
+    """
+    Search the given file, which is in hosts(5) standard format, for an address
+    entry with a given name.
+
+    @param hostsFile: The name of the hosts(5)-format file to search.
+    @type hostsFile: L{FilePath}
+
+    @param name: The name to search for.
+    @type name: C{bytes}
+
+    @return: L{None} if the name is not found in the file, otherwise a
+        C{str} giving the address in the file associated with the name.
+    """
+    results = []
+    try:
+        lines = hostsFile.getContent().splitlines()
+    except:
+        return results
+
+    name = name.lower()
+    for line in lines:
+        idx = line.find(b'#')
+        if idx != -1:
+            line = line[:idx]
+        if not line:
+            continue
+        parts = line.split()
+
+        if name.lower() in [s.lower() for s in parts[1:]]:
+            results.append(nativeString(parts[0]))
+    return results
+
+
+
+def searchFileFor(file, name):
+    """
+    Grep given file, which is in hosts(5) standard format, for an address
+    entry with a given name.
+
+    @param file: The name of the hosts(5)-format file to search.
+    @type file: C{str} or C{bytes}
+
+    @param name: The name to search for.
+    @type name: C{bytes}
+
+    @return: L{None} if the name is not found in the file, otherwise a
+        C{str} giving the first address in the file associated with
+        the name.
+    """
+    addresses = searchFileForAll(FilePath(file), name)
+    if addresses:
+        return addresses[0]
+    return None
+
+
+
+class Resolver(common.ResolverBase):
+    """
+    A resolver that services hosts(5) format files.
+    """
+    def __init__(self, file=b'/etc/hosts', ttl = 60 * 60):
+        common.ResolverBase.__init__(self)
+        self.file = file
+        self.ttl = ttl
+
+
+    def _aRecords(self, name):
+        """
+        Return a tuple of L{dns.RRHeader} instances for all of the IPv4
+        addresses in the hosts file.
+        """
+        return tuple([
+            dns.RRHeader(name, dns.A, dns.IN, self.ttl,
+                         dns.Record_A(addr, self.ttl))
+            for addr
+            in searchFileForAll(FilePath(self.file), name)
+            if isIPAddress(addr)])
+
+
+    def _aaaaRecords(self, name):
+        """
+        Return a tuple of L{dns.RRHeader} instances for all of the IPv6
+        addresses in the hosts file.
+        """
+        return tuple([
+            dns.RRHeader(name, dns.AAAA, dns.IN, self.ttl,
+                         dns.Record_AAAA(addr, self.ttl))
+            for addr
+            in searchFileForAll(FilePath(self.file), name)
+            if not isIPAddress(addr)])
+
+
+    def _respond(self, name, records):
+        """
+        Generate a response for the given name containing the given result
+        records, or a failure if there are no result records.
+
+        @param name: The DNS name the response is for.
+        @type name: C{str}
+
+        @param records: A tuple of L{dns.RRHeader} instances giving the results
+            that will go into the response.
+
+        @return: A L{Deferred} which will fire with a three-tuple of result
+            records, authority records, and additional records, or which will
+            fail with L{dns.DomainError} if there are no result records.
+        """
+        if records:
+            return defer.succeed((records, (), ()))
+        return defer.fail(failure.Failure(dns.DomainError(name)))
+
+
+    def lookupAddress(self, name, timeout=None):
+        """
+        Read any IPv4 addresses from C{self.file} and return them as
+        L{Record_A} instances.
+        """
+        name = dns.domainString(name)
+        return self._respond(name, self._aRecords(name))
+
+
+    def lookupIPV6Address(self, name, timeout=None):
+        """
+        Read any IPv6 addresses from C{self.file} and return them as
+        L{Record_AAAA} instances.
+        """
+        name = dns.domainString(name)
+        return self._respond(name, self._aaaaRecords(name))
+
+    # Someday this should include IPv6 addresses too, but that will cause
+    # problems if users of the API (mainly via getHostByName) aren't updated to
+    # know about IPv6 first.
+    lookupAllRecords = lookupAddress