add python_bindings_example for python3

Signed-off-by: Sven Ebenfeld <sven.ebenfeld@gmail.com>

1 files changed, 157 insertions, 0 deletions

diff --git a/python3_bindings_example.py b/python3_bindings_example.py
new file mode 100644
index 0000000..fb24eff
--- /dev/null
+++ b/python3_bindings_example.py
@@ -0,0 +1,157 @@
+#!/usr/bin/env python3
+"""
+Copyright (c) 2015-2018 Nitrokey UG
+
+This file is part of libnitrokey.
+
+libnitrokey 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 3 of the License, or
+any later version.
+
+libnitrokey 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 General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with libnitrokey. If not, see <http://www.gnu.org/licenses/>.
+
+SPDX-License-Identifier: LGPL-3.0
+"""
+
+import cffi
+from enum import Enum
+
+"""
+This example will print 10 HOTP codes from just written HOTP#2 slot.
+For more examples of use please refer to unittest/test_*.py files.
+"""
+
+ffi = cffi.FFI()
+get_string = ffi.string
+
+class DeviceErrorCode(Enum):
+    STATUS_OK = 0
+    NOT_PROGRAMMED = 3
+    WRONG_PASSWORD = 4
+    STATUS_NOT_AUTHORIZED = 5
+    STATUS_AES_DEC_FAILED = 0xa
+
+
+def get_library():
+    fp = 'NK_C_API.h'  # path to C API header
+
+    declarations = []
+    with open(fp, 'r') as f:
+        declarations = f.readlines()
+
+    cnt = 0
+    a = iter(declarations)
+    for declaration in a:
+        if declaration.strip().startswith('NK_C_API'):
+            declaration = declaration.replace('NK_C_API', '').strip()
+            while ';' not in declaration:
+                declaration += (next(a)).strip()
+            # print(declaration)
+            ffi.cdef(declaration, override=True)
+            cnt +=1
+    print('Imported {} declarations'.format(cnt))
+
+
+    C = None
+    import os, sys
+    path_build = os.path.join(".", "build")
+    paths = [
+            os.environ.get('LIBNK_PATH', None),
+            os.path.join(path_build,"libnitrokey.so"),
+            os.path.join(path_build,"libnitrokey.dylib"),
+            os.path.join(path_build,"libnitrokey.dll"),
+            os.path.join(path_build,"nitrokey.dll"),
+    ]
+    for p in paths:
+        if not p: continue
+        print("Trying " +p)
+        p = os.path.abspath(p)
+        if os.path.exists(p):
+            print("Found: "+p)
+            C = ffi.dlopen(p)
+            break
+        else:
+            print("File does not exist: " + p)
+    if not C:
+        print("No library file found")
+        print("Please set the path using LIBNK_PATH environment variable to existing library or compile it (see "
+              "README.md for details)")
+        sys.exit(1)
+
+    return C
+
+
+def get_hotp_code(lib, i):
+    return get_string(lib.NK_get_hotp_code(i))
+
+def to_hex(ss):
+    return ''.join([ format(ord(s),'02x') for s in ss ])
+
+print('Warning!')
+print('This example will change your configuration on inserted stick and overwrite your HOTP#2 slot.')
+print('Please write "continue" to continue or any other string to quit')
+a = input()
+
+if not a == 'continue':
+    exit()
+
+ADMIN = input('Please enter your admin PIN (empty string uses 12345678) ')
+ADMIN = ADMIN or '12345678'  # use default if empty string
+
+show_log = input('Should log messages be shown (please write "yes" to enable; this will make harder reading script output) ') == 'yes'
+libnitrokey = get_library()
+
+if show_log:
+    log_level = input('Please select verbosity level (0-5, 2 is library default, 3 will be selected on empty input) ')
+    log_level = log_level or '3'
+    log_level = int(log_level)
+    libnitrokey.NK_set_debug_level(log_level)
+else:
+    libnitrokey.NK_set_debug_level(2)
+
+
+ADMIN_TEMP = '123123123'
+RFC_SECRET = to_hex('12345678901234567890')
+
+# libnitrokey.NK_login('S')  # connect only to Nitrokey Storage device
+# libnitrokey.NK_login('P')  # connect only to Nitrokey Pro device
+device_connected = libnitrokey.NK_login_auto()  # connect to any Nitrokey Stick
+if device_connected:
+    print('Connected to Nitrokey device!')
+else:
+    print('Could not connect to Nitrokey device!')
+    exit()
+
+use_8_digits = True
+pin_correct = libnitrokey.NK_first_authenticate(ADMIN.encode('ascii'), ADMIN_TEMP.encode('ascii')) == DeviceErrorCode.STATUS_OK.value
+if pin_correct:
+    print('Your PIN is correct!')
+else:
+    print('Your PIN is not correct! Please try again. Please be careful to not lock your stick!')
+    retry_count_left = libnitrokey.NK_get_admin_retry_count()
+    print('Retry count left: %d' % retry_count_left )
+    exit()
+
+# For function parameters documentation please check NK_C_API.h
+assert libnitrokey.NK_write_config(255, 255, 255, False, True, ADMIN_TEMP.encode('ascii')) == DeviceErrorCode.STATUS_OK.value
+libnitrokey.NK_first_authenticate(ADMIN.encode('ascii'), ADMIN_TEMP.encode('ascii'))
+libnitrokey.NK_write_hotp_slot(1, 'python_test'.encode('ascii'), RFC_SECRET.encode('ascii'), 0, use_8_digits, False, False, "".encode('ascii'),
+                            ADMIN_TEMP.encode('ascii'))
+# RFC test according to: https://tools.ietf.org/html/rfc4226#page-32
+test_data = [
+    1284755224, 1094287082, 137359152, 1726969429, 1640338314, 868254676, 1918287922, 82162583, 673399871,
+    645520489,
+]
+print('Getting HOTP code from Nitrokey Stick (RFC test, 8 digits): ')
+for i in range(10):
+    hotp_slot_1_code = get_hotp_code(libnitrokey, 1)
+    correct_str =  "correct!" if hotp_slot_1_code.decode('ascii') == str(test_data[i])[-8:] else  "not correct"
+    print('%d: %s, should be %s -> %s' % (i, hotp_slot_1_code.decode('ascii'), str(test_data[i])[-8:], correct_str))
+libnitrokey.NK_logout()  # disconnect device