Adding upstream version 2.2.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

stasadm.py

@@ -0,0 +1,202 @@
+#!/usr/bin/python3
+# Copyright (c) 2021, Dell Inc. or its subsidiaries.  All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+# See the LICENSE file for details.
+#
+# This file is part of NVMe STorage Appliance Services (nvme-stas).
+#
+# Authors: Martin Belanger <Martin.Belanger@dell.com>
+#
+''' STorage Appliance Services Admin Tool '''
+import os
+import sys
+import uuid
+import configparser
+from argparse import ArgumentParser
+from staslib import defs
+
+try:
+    import hmac
+    import hashlib
+except (ImportError, ModuleNotFoundError):
+    hmac = None
+    hashlib = None
+
+
+def read_from_file(fname, size):  # pylint: disable=missing-function-docstring
+    try:
+        with open(fname) as f:  # pylint: disable=unspecified-encoding
+            data = f.read(size)
+        if len(data) == size:
+            return data
+    except FileNotFoundError:
+        pass
+
+    return None
+
+
+def get_machine_app_specific(app_id):
+    '''@brief Get a machine ID specific to an application. We use the
+    value retrieved from /etc/machine-id. The documentation states that
+    /etc/machine-id:
+        "should be considered "confidential", and must not be exposed in
+         untrusted environments, in particular on the network. If a stable
+         unique identifier that is tied to the machine is needed for some
+         application, the machine ID or any part of it must not be used
+         directly. Instead the machine ID should be hashed with a crypto-
+         graphic, keyed hash function, using a fixed, application-specific
+         key. That way the ID will be properly unique, and derived in a
+         constant way from the machine ID but there will be no way to
+         retrieve the original machine ID from the application-specific one"
+
+    @note systemd's C function sd_id128_get_machine_app_specific() was the
+          inspiration for this code.
+
+    @ref https://www.freedesktop.org/software/systemd/man/machine-id.html
+    '''
+    if not hmac:
+        return None
+
+    data = read_from_file('/etc/machine-id', 32)
+    if not data:
+        return None
+
+    hmac_obj = hmac.new(app_id, uuid.UUID(data).bytes, hashlib.sha256)
+    id128_bytes = hmac_obj.digest()[0:16]
+    return str(uuid.UUID(bytes=id128_bytes, version=4))
+
+
+def get_uuid_from_system():
+    '''@brief Try to find system UUID in the following order:
+    1) /etc/machine-id
+    2) /sys/class/dmi/id/product_uuid
+    3) /proc/device-tree/ibm,partition-uuid
+    '''
+    uuid_str = get_machine_app_specific(b'$nvmexpress.org$')
+    if uuid_str:
+        return uuid_str
+
+    # The following files are only readable by root
+    if os.geteuid() != 0:
+        sys.exit('Permission denied. Root privileges required.')
+
+    id128 = read_from_file('/sys/class/dmi/id/product_uuid', 36)
+    if id128:
+        # Swap little-endian to network order per
+        # DMTF SMBIOS 3.0 Section 7.2.1 System UUID.
+        swapped = ''.join([id128[x] for x in (6, 7, 4, 5, 2, 3, 0, 1, 8, 11, 12, 9, 10, 13, 16, 17, 14, 15)])
+        return swapped + id128[18:]
+
+    return read_from_file('/proc/device-tree/ibm,partition-uuid', 36)
+
+
+def save(section, option, string, conf_file, fname):
+    '''@brief Save configuration
+
+    @param section: section in @conf_file where @option will be added
+    @param option: option to be added under @section in @conf_file
+    @param string: Text to be saved to @fname
+    @param conf_file: Configuration file name
+    @param fname: Optional file where @string will be saved
+    '''
+    if fname and string is not None:
+        with open(fname, 'w') as f:  # pylint: disable=unspecified-encoding
+            print(string, file=f)
+
+    if conf_file:
+        config = configparser.ConfigParser(
+            default_section=None, allow_no_value=True, delimiters=('='), interpolation=None, strict=False
+        )
+        if os.path.isfile(conf_file):
+            config.read(conf_file)
+
+        try:
+            config.add_section(section)
+        except configparser.DuplicateSectionError:
+            pass
+
+        if fname:
+            string = 'file://' + fname
+
+        if string is not None:
+            config.set(section, option, string)
+        else:
+            config.remove_option(section, option)
+
+        with open(conf_file, 'w') as f:  # pylint: disable=unspecified-encoding
+            config.write(f)
+
+
+def hostnqn(args):
+    '''@brief Configure the host NQN'''
+    uuid_str = get_uuid_from_system() or str(uuid.uuid4())
+    uuid_str = f'nqn.2014-08.org.nvmexpress:uuid:{uuid_str}'
+    save('Host', 'nqn', uuid_str, args.conf_file, args.file)
+
+
+def hostid(args):
+    '''@brief Configure the host ID'''
+    save('Host', 'id', str(uuid.uuid4()), args.conf_file, args.file)
+
+
+def set_symname(args):
+    '''@brief Define the host Symbolic Name'''
+    save('Host', 'symname', args.symname, args.conf_file, args.file)
+
+
+def clr_symname(args):
+    '''@brief Undefine the host NQN'''
+    save('Host', 'symname', None, args.conf_file, None)
+
+
+def get_parser():  # pylint: disable=missing-function-docstring
+    parser = ArgumentParser(description='Configuration utility for STAS.')
+    parser.add_argument('-v', '--version', action='store_true', help='Print version, then exit', default=False)
+    parser.add_argument(
+        '-c',
+        '--conf-file',
+        action='store',
+        help='Configuration file. Default %(default)s.',
+        default=defs.SYS_CONF_FILE,
+        type=str,
+        metavar='FILE',
+    )
+
+    subparser = parser.add_subparsers(title='Commands')
+
+    prsr = subparser.add_parser('hostnqn', help='Configure the host NQN. The NQN is auto-generated.')
+    prsr.add_argument(
+        '-f', '--file', action='store', help='Optional file where to save the NQN.', type=str, metavar='FILE'
+    )
+    prsr.set_defaults(cmd=hostnqn)
+
+    prsr = subparser.add_parser('hostid', help='Configure the host ID. The ID is auto-generated.')
+    prsr.add_argument(
+        '-f', '--file', action='store', help='Optional file where to save the ID.', type=str, metavar='FILE'
+    )
+    prsr.set_defaults(cmd=hostid)
+
+    prsr = subparser.add_parser('set-symname', help='Set the host symbolic')
+    prsr.add_argument(
+        '-f', '--file', action='store', help='Optional file where to save the symbolic name.', type=str, metavar='FILE'
+    )
+    prsr.add_argument('symname', action='store', help='Symbolic name', default=None, metavar='SYMNAME')
+    prsr.set_defaults(cmd=set_symname)
+
+    prsr = subparser.add_parser('clear-symname', help='Clear the host symbolic')
+    prsr.set_defaults(cmd=clr_symname)
+
+    return parser
+
+
+PARSER = get_parser()
+ARGS = PARSER.parse_args()
+if ARGS.version:
+    print(f'nvme-stas {defs.VERSION}')
+    sys.exit(0)
+
+try:
+    ARGS.cmd(ARGS)
+except AttributeError as ex:
+    print(str(ex))
+    PARSER.print_usage()