implement a getent command to query nslcd while bypassing NSS stack

author: Arthur de Jong <arthur@arthurdejong.org> 2013-01-28 23:13:22 +0100
committer: Arthur de Jong <arthur@arthurdejong.org> 2013-02-08 21:29:02 +0100
commit: ded7bd226b51975544cd5bf4f8799787948ffccb (patch)
tree: d150297c56ea23c7a646123c844534bc9ec93609
parent: 3117668c15cf88f877a538035875cd0f75ce821c (diff)
4 files changed, 518 insertions, 0 deletions
diff --git a/utils/Makefile.am b/utils/Makefile.am
index e39d7da..e9233d8 100644
--- a/utils/Makefile.am
+++ b/utils/Makefile.am
@@ -19,6 +19,7 @@
 
 utilsdir = $(datadir)/nslcdutils
 
+utils_PYTHON = cmdline.py getent.py nslcd.py
 nodist_utils_PYTHON = constants.py
 CLEANFILES = $(nodist_utils_PYTHON)
 
@@ -31,3 +32,11 @@ clean-local:
 # copy constants module
 constants.py: ../pynslcd/constants.py
 	cp ../pynslcd/constants.py .
+
+# create symbolic links to the commands and fix permissions
+install-data-hook:
+	$(MKDIR_P) $(DESTDIR)$(bindir)
+	set -ex; for cmd in getent ; do \
+	  chmod a+rx $(DESTDIR)$(utilsdir)/$$cmd.py ; \
+	  [ -L $(DESTDIR)$(bindir)/$$cmd.ldap ] || $(LN_S) $(utilsdir)/$$cmd.py $(DESTDIR)$(bindir)/$$cmd.ldap ; \
+	done
diff --git a/utils/cmdline.py b/utils/cmdline.py
new file mode 100644
index 0000000..eb84fe3
--- /dev/null
+++ b/utils/cmdline.py
@@ -0,0 +1,50 @@
+# coding: utf-8
+
+# cmdline.py - functions for handling command-line options
+#
+# Copyright (C) 2013 Arthur de Jong
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301 USA
+
+import argparse
+
+import constants
+
+
+version_string = '''
+%s
+Written by Arthur de Jong.
+
+Copyright (C) 2013 Arthur de Jong
+This is free software; see the source for copying conditions.  There is NO
+warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+'''.strip() % constants.PACKAGE_STRING
+
+
+class VersionAction(argparse.Action):
+
+    def __init__(self, option_strings, dest,
+                 help='output version information and exit'):
+        super(VersionAction, self).__init__(
+            option_strings=option_strings,
+            dest=argparse.SUPPRESS,
+            default=argparse.SUPPRESS,
+            nargs=0,
+            help=help)
+
+    def __call__(self, parser, namespace, values, option_string=None):
+        print version_string
+        parser.exit()
diff --git a/utils/getent.py b/utils/getent.py
new file mode 100755
index 0000000..3279249
--- /dev/null
+++ b/utils/getent.py
@@ -0,0 +1,346 @@
+#!/usr/bin/env python
+# coding: utf-8
+
+# getent.py - program for querying nslcd
+#
+# Copyright (C) 2013 Arthur de Jong
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301 USA
+
+import argparse
+import re
+import socket
+import struct
+import sys
+
+from cmdline import VersionAction
+import constants
+from nslcd import NslcdClient
+
+
+# set up command line parser
+parser = argparse.ArgumentParser(
+        description='Query information in LDAP.',
+        epilog='Report bugs to <%s>.' % constants.PACKAGE_BUGREPORT
+    )
+parser.add_argument('-V', '--version', action=VersionAction)
+parser.add_argument('database', metavar='DATABASE',
+    help='any of those supported by nslcd')
+parser.add_argument('key', metavar='KEY', nargs='?',
+    help='information to lookup')
+
+
+# parse arguments
+args = parser.parse_args()
+
+
+def getent_aliases(database, key=None):
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_ALIAS_ALL)
+    else:
+        con = NslcdClient(constants.NSLCD_ACTION_ALIAS_BYNAME)
+        con.write_string(key)
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        print '%-16s%s' % (
+                con.read_string() + ': ',
+                ', '.join(con.read_stringlist()),
+            )
+
+
+def getent_ethers(database, key=None):
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_ETHER_ALL)
+    elif re.match('^[0-9a-fA-F]{1,2}(:[0-9a-fA-F]{1,2}){5}$', key):
+        con = NslcdClient(constants.NSLCD_ACTION_ETHER_BYETHER)
+        con.write_ether(key)
+    else:
+        con = NslcdClient(constants.NSLCD_ACTION_ETHER_BYNAME)
+        con.write_string(key)
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        name = con.read_string()
+        ether = con.read_ether()
+        print '%s %s' % (ether, name)
+
+
+def getent_group(database, key=None):
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_GROUP_ALL)
+    elif database == 'group.bymember':
+        con = NslcdClient(constants.NSLCD_ACTION_GROUP_BYMEMBER)
+        con.write_string(key)
+    elif re.match('^\d+$', key):
+        con = NslcdClient(constants.NSLCD_ACTION_GROUP_BYGID)
+        con.write_int32(int(key))
+    else:
+        con = NslcdClient(constants.NSLCD_ACTION_GROUP_BYNAME)
+        con.write_string(key)
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        print '%s:%s:%d:%s' % (
+                con.read_string(),
+                con.read_string(),
+                con.read_int32(),
+                ','.join(con.read_stringlist()),
+            )
+
+
+def _get_ipv4(value):
+    try:
+        return socket.inet_pton(socket.AF_INET, value)
+    except socket.error:
+        return None
+
+
+def _get_ipv6(value):
+    try:
+        return socket.inet_pton(socket.AF_INET6, value)
+    except socket.error:
+        return None
+
+
+def _get_af(database):
+    if database.endswith('v4'):
+        return socket.AF_INET
+    elif database.endswith('v6'):
+        return socket.AF_INET6
+    else:
+        return None
+
+
+def getent_hosts(database, key=None):
+    db_af = _get_af(database)
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_HOST_ALL)
+    else:
+        ipv4_addr = _get_ipv4(key)
+        ipv6_addr = _get_ipv6(key)
+        if ipv4_addr and db_af in (socket.AF_INET, None):
+            con = NslcdClient(constants.NSLCD_ACTION_HOST_BYADDR)
+            con.write_address(socket.AF_INET, ipv4_addr)
+        elif ipv6_addr and db_af in (socket.AF_INET, None):
+            con = NslcdClient(constants.NSLCD_ACTION_HOST_BYADDR)
+            con.write_address(socket.AF_INET6, ipv6_addr)
+        else:
+            con = NslcdClient(constants.NSLCD_ACTION_HOST_BYNAME)
+            con.write_string(key)
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        names = ' '.join([con.read_string()] + con.read_stringlist())
+        for af, address in con.read_addresslist():
+            if db_af in (af, None):
+                print '%-15s %s' % (address, names)
+
+
+def _read_netgroup(con):
+    """Read netgroup name, members and tripples from stream."""
+    name = con.read_string()
+    members = []
+    tripples = []
+    while True:
+        member_type = con.read_int32()
+        if member_type == constants.NSLCD_NETGROUP_TYPE_NETGROUP:
+            members.append(con.read_string())
+        elif member_type == constants.NSLCD_NETGROUP_TYPE_TRIPLE:
+            tripples.append((
+                    con.read_string(), con.read_string(),
+                    con.read_string()
+                ))
+        else:
+            break
+    return name, members, tripples
+
+
+def _get_getgroups(con, recurse, netgroups=None):
+    if netgroups is None:
+        netgroups = {}
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        name, members, tripples = _read_netgroup(con)
+        if not recurse:
+            yield (name, members, tripples)
+        else:
+            netgroups[name] = None
+            for netgroup in members:
+                if netgroup not in netgroups:
+                    con2 = NslcdClient(constants.NSLCD_ACTION_NETGROUP_BYNAME)
+                    con2.write_string(netgroup)
+                    all(_get_getgroups(con2, recurse, netgroups))
+                if netgroups.get(netgroup, None) is not None:
+                    tripples += netgroups[netgroup][1]
+            netgroups[name] = (members, tripples)
+            yield (name, [], tripples)
+
+
+def getent_netgroup(database, key=None):
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_NETGROUP_ALL)
+    else:
+        con = NslcdClient(constants.NSLCD_ACTION_NETGROUP_BYNAME)
+        con.write_string(key)
+    for name, members, tripples in _get_getgroups(con, database == 'netgroup'):
+        print '%-15s %s' % (name, ' '.join(
+                members +
+                ['(%s, %s, %s)' % (host, user, domain)
+                 for host, user, domain in tripples]
+            ))
+
+
+def getent_networks(database, key=None):
+    db_af = _get_af(database)
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_NETWORK_ALL)
+    else:
+        ipv4_addr = _get_ipv4(key)
+        ipv6_addr = _get_ipv6(key)
+        if ipv4_addr and db_af in (socket.AF_INET, None):
+            con = NslcdClient(constants.NSLCD_ACTION_NETWORK_BYADDR)
+            con.write_address(socket.AF_INET, ipv4_addr)
+        elif ipv6_addr and db_af in (socket.AF_INET, None):
+            con = NslcdClient(constants.NSLCD_ACTION_NETWORK_BYADDR)
+            con.write_address(socket.AF_INET6, ipv6_addr)
+        else:
+            con = NslcdClient(constants.NSLCD_ACTION_NETWORK_BYNAME)
+            con.write_string(key)
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        names = ' '.join([con.read_string()] + con.read_stringlist())
+        for af, address in con.read_addresslist():
+            if db_af in (af, None):
+                print '%-15s %s' % (address, names)
+
+
+def getent_passwd(database, key=None):
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_PASSWD_ALL)
+    elif re.match('^\d+$', key):
+        con = NslcdClient(constants.NSLCD_ACTION_PASSWD_BYUID)
+        con.write_int32(int(key))
+    else:
+        con = NslcdClient(constants.NSLCD_ACTION_PASSWD_BYNAME)
+        con.write_string(key)
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        print '%s:%s:%d:%d:%s:%s:%s' % (
+                con.read_string(),
+                con.read_string(),
+                con.read_int32(),
+                con.read_int32(),
+                con.read_string(),
+                con.read_string(),
+                con.read_string(),
+            )
+
+
+def getent_protocols(database, key=None):
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_PROTOCOL_ALL)
+    elif re.match('^\d+$', key):
+        con = NslcdClient(constants.NSLCD_ACTION_PROTOCOL_BYNUMBER)
+        con.write_int32(int(key))
+    else:
+        con = NslcdClient(constants.NSLCD_ACTION_PROTOCOL_BYNAME)
+        con.write_string(key)
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        name = con.read_string()
+        aliases = con.read_stringlist()
+        number = con.read_int32()
+        print '%-21s %d %s' % (name, number, ' '.join(aliases))
+
+
+def getent_rpc(database, key=None):
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_RPC_ALL)
+    elif re.match('^\d+$', key):
+        con = NslcdClient(constants.NSLCD_ACTION_RPC_BYNUMBER)
+        con.write_int32(int(key))
+    else:
+        con = NslcdClient(constants.NSLCD_ACTION_RPC_BYNAME)
+        con.write_string(key)
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        name = con.read_string()
+        aliases = con.read_stringlist()
+        number = con.read_int32()
+        print '%-15s %d  %s' % (name, number, ' '.join(aliases))
+
+
+def getent_services(database, key=None):
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_SERVICE_ALL)
+    else:
+        value = key
+        protocol = ''
+        if '/' in value:
+            value, protocol = value.split('/', 1)
+        if re.match('^\d+$', value):
+            con = NslcdClient(constants.NSLCD_ACTION_SERVICE_BYNUMBER)
+            con.write_int32(int(value))
+            con.write_string(protocol)
+        else:
+            con = NslcdClient(constants.NSLCD_ACTION_SERVICE_BYNAME)
+            con.write_string(value)
+            con.write_string(protocol)
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        name = con.read_string()
+        aliases = con.read_stringlist()
+        number = con.read_int32()
+        protocol = con.read_string()
+        print '%-21s %d/%s %s' % (name, number, protocol, ' '.join(aliases))
+
+
+def getent_shadow(database, key=None):
+    if not key:
+        con = NslcdClient(constants.NSLCD_ACTION_SHADOW_ALL)
+    else:
+        con = NslcdClient(constants.NSLCD_ACTION_SHADOW_BYNAME)
+        con.write_string(key)
+    value2str = lambda x: str(x) if x != -1 else ''
+    while con.get_response() == constants.NSLCD_RESULT_BEGIN:
+        print '%s:%s:%s:%s:%s:%s:%s:%s:%s' % (
+                con.read_string(),
+                con.read_string(),
+                value2str(con.read_int32()),
+                value2str(con.read_int32()),
+                value2str(con.read_int32()),
+                value2str(con.read_int32()),
+                value2str(con.read_int32()),
+                value2str(con.read_int32()),
+                value2str(con.read_int32()),
+            )
+
+
+try:
+    if args.database == 'aliases':
+        getent_aliases(args.database, args.key)
+    elif args.database == 'ethers':
+        getent_ethers(args.database, args.key)
+    elif args.database in ('group', 'group.bymember'):
+        getent_group(args.database, args.key)
+    elif args.database in ('hosts', 'hostsv4', 'hostsv6'):
+        getent_hosts(args.database, args.key)
+    elif args.database in ('netgroup', 'netgroup.norec'):
+        getent_netgroup(args.database, args.key)
+    elif args.database in ('networks', 'networksv4', 'networksv6'):
+        getent_networks(args.database, args.key)
+    elif args.database == 'passwd':
+        getent_passwd(args.database, args.key)
+    elif args.database == 'protocols':
+        getent_protocols(args.database, args.key)
+    elif args.database == 'rpc':
+        getent_rpc(args.database, args.key)
+    elif args.database == 'services':
+        getent_services(args.database, args.key)
+    elif args.database == 'shadow':
+        getent_shadow(args.database, args.key)
+    else:
+        parser.error('Unknown database: %s' % args.database)
+except struct.error:
+    print 'Problem contacting nslcd'
+    sys.exit(1)
diff --git a/utils/nslcd.py b/utils/nslcd.py
new file mode 100644
index 0000000..06165cc
--- /dev/null
+++ b/utils/nslcd.py
@@ -0,0 +1,113 @@
+# coding: utf-8
+
+# nslcd.py - functions for doing nslcd requests
+#
+# Copyright (C) 2013 Arthur de Jong
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301 USA
+
+import os
+import socket
+import struct
+import fcntl
+
+import constants
+
+
+# definition for reading and writing INT32 values
+_int32 = struct.Struct('!i')
+
+
+class NslcdClient(object):
+
+    def __init__(self, action):
+        # set up the socket (store in class to avoid closing it)
+        self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+        #fcntl.fcntl(sock, fcntl.F_SETFD, fcntl.FD_CLOEXEC)
+        # connect to nslcd
+        self.sock.connect(constants.NSLCD_SOCKET)
+        #self.sock.setblocking(1)
+        self.fp = os.fdopen(self.sock.fileno(), 'r+b', 1024 * 1024)
+        # write a request header with a request code
+        self.action = action
+        self.write_int32(constants.NSLCD_VERSION)
+        self.write_int32(action)
+
+    def write(self, value):
+        self.fp.write(value)
+
+    def write_int32(self, value):
+        self.write(_int32.pack(value))
+
+    def write_string(self, value):
+        self.write_int32(len(value))
+        self.write(value)
+
+    def write_ether(self, value):
+        value = struct.pack('BBBBBB', *(int(x, 16) for x in value.split(':')))
+        self.write(value)
+
+    def write_address(self, af, value):
+        self.write_int32(af)
+        self.write_string(value)
+
+    def read(self, size):
+        return self.fp.read(size)
+
+    def read_int32(self):
+        return _int32.unpack(self.read(_int32.size))[0]
+
+    def read_string(self):
+        len = self.read_int32()
+        return self.read(len)
+
+    def read_stringlist(self):
+        len = self.read_int32()
+        return [self.read_string() for x in xrange(len)]
+
+    def read_ether(self):
+        value = self.fp.read(6)
+        return ':'.join('%x' % x for x in struct.unpack('6B', value))
+
+    def read_address(self):
+        af = self.read_int32()
+        return af, socket.inet_ntop(af, self.read_string())
+
+    def read_addresslist(self):
+        len = self.read_int32()
+        return [self.read_address() for x in xrange(len)]
+
+    def get_response(self):
+        # complete the request if required and check response header
+        if self.action:
+            # flush the stream
+            self.fp.flush()
+            # read and check response version number
+            assert self.read_int32() == constants.NSLCD_VERSION
+            assert self.read_int32() == self.action
+            self.action = None
+        # get the NSLCD_RESULT_* marker and return it
+        return self.read_int32()
+
+    def close(self):
+        if hasattr(self, 'fp'):
+            try:
+                self.fp.close()
+            except IOError:
+                pass
+
+    def __del__(self):
+        self.close()
author	Arthur de Jong <arthur@arthurdejong.org>	2013-01-28 23:13:22 +0100
committer	Arthur de Jong <arthur@arthurdejong.org>	2013-02-08 21:29:02 +0100
commit	ded7bd226b51975544cd5bf4f8799787948ffccb (patch)
tree	d150297c56ea23c7a646123c844534bc9ec93609
parent	3117668c15cf88f877a538035875cd0f75ce821c (diff)