# -*- coding: utf-8 -*-
#
#  SelfTest/Cipher/test_pkcs1_oaep.py: Self-test for PKCS#1 OAEP encryption
#
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# the extent that dedication to the public domain is not available,
# everyone is granted a worldwide, perpetual, royalty-free,
# non-exclusive license to exercise all rights associated with the
# contents of this file for any purpose whatsoever.
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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import unittest

from Crypto.SelfTest.st_common import list_test_cases, a2b_hex, b2a_hex

from Crypto.Util.py3compat import b, bchr
from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_OAEP as PKCS
from Crypto.Hash import MD2,MD5,SHA1,SHA256,RIPEMD160
from Crypto import Random

def rws(t):
    """Remove white spaces, tabs, and new lines from a string"""
    for c in ['\n', '\t', ' ']:
        t = t.replace(c,'')
    return t

def t2b(t):
    """Convert a text string with bytes in hex form to a byte string"""
    clean = rws(t)
    if len(clean)%2 == 1:
        raise ValueError("Even number of characters expected")
    return a2b_hex(clean)

class PKCS1_OAEP_Tests(unittest.TestCase):

        def setUp(self):
                self.rng = Random.new().read
                self.key1024 = RSA.generate(1024, self.rng)

        # List of tuples with test data for PKCS#1 OAEP
        # Each tuple is made up by:
        #       Item #0: dictionary with RSA key component
        #       Item #1: plaintext
        #       Item #2: ciphertext
        #       Item #3: random data (=seed)
        #       Item #4: hash object

        _testData = (

                #
                # From in oaep-int.txt to be found in
                # ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1/pkcs-1v2-1-vec.zip
                #
                (
                # Private key
                {
                'n':'''bb f8 2f 09 06 82 ce 9c 23 38 ac 2b 9d a8 71 f7
                36 8d 07 ee d4 10 43 a4 40 d6 b6 f0 74 54 f5 1f
                b8 df ba af 03 5c 02 ab 61 ea 48 ce eb 6f cd 48
                76 ed 52 0d 60 e1 ec 46 19 71 9d 8a 5b 8b 80 7f
                af b8 e0 a3 df c7 37 72 3e e6 b4 b7 d9 3a 25 84
                ee 6a 64 9d 06 09 53 74 88 34 b2 45 45 98 39 4e
                e0 aa b1 2d 7b 61 a5 1f 52 7a 9a 41 f6 c1 68 7f
                e2 53 72 98 ca 2a 8f 59 46 f8 e5 fd 09 1d bd cb''',
                # Public key
                'e':'11',
                # In the test vector, only p and q were given...
                # d is computed offline as e^{-1} mod (p-1)(q-1)
                'd':'''a5dafc5341faf289c4b988db30c1cdf83f31251e0
                668b42784813801579641b29410b3c7998d6bc465745e5c3
                92669d6870da2c082a939e37fdcb82ec93edac97ff3ad595
                0accfbc111c76f1a9529444e56aaf68c56c092cd38dc3bef
                5d20a939926ed4f74a13eddfbe1a1cecc4894af9428c2b7b
                8883fe4463a4bc85b1cb3c1'''
                }
                ,
                # Plaintext
                '''d4 36 e9 95 69 fd 32 a7 c8 a0 5b bc 90 d3 2c 49''',
                # Ciphertext
                '''12 53 e0 4d c0 a5 39 7b b4 4a 7a b8 7e 9b f2 a0
                39 a3 3d 1e 99 6f c8 2a 94 cc d3 00 74 c9 5d f7
                63 72 20 17 06 9e 52 68 da 5d 1c 0b 4f 87 2c f6
                53 c1 1d f8 23 14 a6 79 68 df ea e2 8d ef 04 bb
                6d 84 b1 c3 1d 65 4a 19 70 e5 78 3b d6 eb 96 a0
                24 c2 ca 2f 4a 90 fe 9f 2e f5 c9 c1 40 e5 bb 48
                da 95 36 ad 87 00 c8 4f c9 13 0a de a7 4e 55 8d
                51 a7 4d df 85 d8 b5 0d e9 68 38 d6 06 3e 09 55''',
                # Random
                '''aa fd 12 f6 59 ca e6 34 89 b4 79 e5 07 6d de c2
                f0 6c b5 8f''',
                # Hash
                SHA1,
               ),

                #
                # From in oaep-vect.txt to be found in Example 1.1
                # ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1/pkcs-1v2-1-vec.zip
                #
                (
                # Private key
                {
                'n':'''a8 b3 b2 84 af 8e b5 0b 38 70 34 a8 60 f1 46 c4
                91 9f 31 87 63 cd 6c 55 98 c8 ae 48 11 a1 e0 ab
                c4 c7 e0 b0 82 d6 93 a5 e7 fc ed 67 5c f4 66 85
                12 77 2c 0c bc 64 a7 42 c6 c6 30 f5 33 c8 cc 72
                f6 2a e8 33 c4 0b f2 58 42 e9 84 bb 78 bd bf 97
                c0 10 7d 55 bd b6 62 f5 c4 e0 fa b9 84 5c b5 14
                8e f7 39 2d d3 aa ff 93 ae 1e 6b 66 7b b3 d4 24
                76 16 d4 f5 ba 10 d4 cf d2 26 de 88 d3 9f 16 fb''',
                'e':'''01 00 01''',
                'd':'''53 33 9c fd b7 9f c8 46 6a 65 5c 73 16 ac a8 5c
                55 fd 8f 6d d8 98 fd af 11 95 17 ef 4f 52 e8 fd
                8e 25 8d f9 3f ee 18 0f a0 e4 ab 29 69 3c d8 3b
                15 2a 55 3d 4a c4 d1 81 2b 8b 9f a5 af 0e 7f 55
                fe 73 04 df 41 57 09 26 f3 31 1f 15 c4 d6 5a 73
                2c 48 31 16 ee 3d 3d 2d 0a f3 54 9a d9 bf 7c bf
                b7 8a d8 84 f8 4d 5b eb 04 72 4d c7 36 9b 31 de
                f3 7d 0c f5 39 e9 cf cd d3 de 65 37 29 ea d5 d1 '''
                }
                ,
                # Plaintext
                '''66 28 19 4e 12 07 3d b0 3b a9 4c da 9e f9 53 23
                97 d5 0d ba 79 b9 87 00 4a fe fe 34''',
                # Ciphertext
                '''35 4f e6 7b 4a 12 6d 5d 35 fe 36 c7 77 79 1a 3f
                7b a1 3d ef 48 4e 2d 39 08 af f7 22 fa d4 68 fb
                21 69 6d e9 5d 0b e9 11 c2 d3 17 4f 8a fc c2 01
                03 5f 7b 6d 8e 69 40 2d e5 45 16 18 c2 1a 53 5f
                a9 d7 bf c5 b8 dd 9f c2 43 f8 cf 92 7d b3 13 22
                d6 e8 81 ea a9 1a 99 61 70 e6 57 a0 5a 26 64 26
                d9 8c 88 00 3f 84 77 c1 22 70 94 a0 d9 fa 1e 8c
                40 24 30 9c e1 ec cc b5 21 00 35 d4 7a c7 2e 8a''',
                # Random
                '''18 b7 76 ea 21 06 9d 69 77 6a 33 e9 6b ad 48 e1
                dd a0 a5 ef''',
                SHA1
                ),

                #
                # From in oaep-vect.txt to be found in Example 2.1
                # ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1/pkcs-1v2-1-vec.zip
                #
                (
                # Private key
                {
                'n':'''01 94 7c 7f ce 90 42 5f 47 27 9e 70 85 1f 25 d5
                e6 23 16 fe 8a 1d f1 93 71 e3 e6 28 e2 60 54 3e
                49 01 ef 60 81 f6 8c 0b 81 41 19 0d 2a e8 da ba
                7d 12 50 ec 6d b6 36 e9 44 ec 37 22 87 7c 7c 1d
                0a 67 f1 4b 16 94 c5 f0 37 94 51 a4 3e 49 a3 2d
                de 83 67 0b 73 da 91 a1 c9 9b c2 3b 43 6a 60 05
                5c 61 0f 0b af 99 c1 a0 79 56 5b 95 a3 f1 52 66
                32 d1 d4 da 60 f2 0e da 25 e6 53 c4 f0 02 76 6f
                45''',
                'e':'''01 00 01''',
                'd':'''08 23 f2 0f ad b5 da 89 08 8a 9d 00 89 3e 21 fa
                4a 1b 11 fb c9 3c 64 a3 be 0b aa ea 97 fb 3b 93
                c3 ff 71 37 04 c1 9c 96 3c 1d 10 7a ae 99 05 47
                39 f7 9e 02 e1 86 de 86 f8 7a 6d de fe a6 d8 cc
                d1 d3 c8 1a 47 bf a7 25 5b e2 06 01 a4 a4 b2 f0
                8a 16 7b 5e 27 9d 71 5b 1b 45 5b dd 7e ab 24 59
                41 d9 76 8b 9a ce fb 3c cd a5 95 2d a3 ce e7 25
                25 b4 50 16 63 a8 ee 15 c9 e9 92 d9 24 62 fe 39'''
                },
                # Plaintext
                '''8f f0 0c aa 60 5c 70 28 30 63 4d 9a 6c 3d 42 c6
                52 b5 8c f1 d9 2f ec 57 0b ee e7''',
                # Ciphertext
                '''01 81 af 89 22 b9 fc b4 d7 9d 92 eb e1 98 15 99
                2f c0 c1 43 9d 8b cd 49 13 98 a0 f4 ad 3a 32 9a
                5b d9 38 55 60 db 53 26 83 c8 b7 da 04 e4 b1 2a
                ed 6a ac df 47 1c 34 c9 cd a8 91 ad dc c2 df 34
                56 65 3a a6 38 2e 9a e5 9b 54 45 52 57 eb 09 9d
                56 2b be 10 45 3f 2b 6d 13 c5 9c 02 e1 0f 1f 8a
                bb 5d a0 d0 57 09 32 da cf 2d 09 01 db 72 9d 0f
                ef cc 05 4e 70 96 8e a5 40 c8 1b 04 bc ae fe 72
                0e''',
                # Random
                '''8c 40 7b 5e c2 89 9e 50 99 c5 3e 8c e7 93 bf 94
                e7 1b 17 82''',
                SHA1
                ),

                #
                # From in oaep-vect.txt to be found in Example 10.1
                # ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-1/pkcs-1v2-1-vec.zip
                #
                (
                # Private key
                {
                'n':'''ae 45 ed 56 01 ce c6 b8 cc 05 f8 03 93 5c 67 4d
                db e0 d7 5c 4c 09 fd 79 51 fc 6b 0c ae c3 13 a8
                df 39 97 0c 51 8b ff ba 5e d6 8f 3f 0d 7f 22 a4
                02 9d 41 3f 1a e0 7e 4e be 9e 41 77 ce 23 e7 f5
                40 4b 56 9e 4e e1 bd cf 3c 1f b0 3e f1 13 80 2d
                4f 85 5e b9 b5 13 4b 5a 7c 80 85 ad ca e6 fa 2f
                a1 41 7e c3 76 3b e1 71 b0 c6 2b 76 0e de 23 c1
                2a d9 2b 98 08 84 c6 41 f5 a8 fa c2 6b da d4 a0
                33 81 a2 2f e1 b7 54 88 50 94 c8 25 06 d4 01 9a
                53 5a 28 6a fe b2 71 bb 9b a5 92 de 18 dc f6 00
                c2 ae ea e5 6e 02 f7 cf 79 fc 14 cf 3b dc 7c d8
                4f eb bb f9 50 ca 90 30 4b 22 19 a7 aa 06 3a ef
                a2 c3 c1 98 0e 56 0c d6 4a fe 77 95 85 b6 10 76
                57 b9 57 85 7e fd e6 01 09 88 ab 7d e4 17 fc 88
                d8 f3 84 c4 e6 e7 2c 3f 94 3e 0c 31 c0 c4 a5 cc
                36 f8 79 d8 a3 ac 9d 7d 59 86 0e aa da 6b 83 bb''',
                'e':'''01 00 01''',
                'd':'''05 6b 04 21 6f e5 f3 54 ac 77 25 0a 4b 6b 0c 85
                25 a8 5c 59 b0 bd 80 c5 64 50 a2 2d 5f 43 8e 59
                6a 33 3a a8 75 e2 91 dd 43 f4 8c b8 8b 9d 5f c0
                d4 99 f9 fc d1 c3 97 f9 af c0 70 cd 9e 39 8c 8d
                19 e6 1d b7 c7 41 0a 6b 26 75 df bf 5d 34 5b 80
                4d 20 1a dd 50 2d 5c e2 df cb 09 1c e9 99 7b be
                be 57 30 6f 38 3e 4d 58 81 03 f0 36 f7 e8 5d 19
                34 d1 52 a3 23 e4 a8 db 45 1d 6f 4a 5b 1b 0f 10
                2c c1 50 e0 2f ee e2 b8 8d ea 4a d4 c1 ba cc b2
                4d 84 07 2d 14 e1 d2 4a 67 71 f7 40 8e e3 05 64
                fb 86 d4 39 3a 34 bc f0 b7 88 50 1d 19 33 03 f1
                3a 22 84 b0 01 f0 f6 49 ea f7 93 28 d4 ac 5c 43
                0a b4 41 49 20 a9 46 0e d1 b7 bc 40 ec 65 3e 87
                6d 09 ab c5 09 ae 45 b5 25 19 01 16 a0 c2 61 01
                84 82 98 50 9c 1c 3b f3 a4 83 e7 27 40 54 e1 5e
                97 07 50 36 e9 89 f6 09 32 80 7b 52 57 75 1e 79'''
                },
                # Plaintext
                '''8b ba 6b f8 2a 6c 0f 86 d5 f1 75 6e 97 95 68 70
                b0 89 53 b0 6b 4e b2 05 bc 16 94 ee''',
                # Ciphertext
                '''53 ea 5d c0 8c d2 60 fb 3b 85 85 67 28 7f a9 15
                52 c3 0b 2f eb fb a2 13 f0 ae 87 70 2d 06 8d 19
                ba b0 7f e5 74 52 3d fb 42 13 9d 68 c3 c5 af ee
                e0 bf e4 cb 79 69 cb f3 82 b8 04 d6 e6 13 96 14
                4e 2d 0e 60 74 1f 89 93 c3 01 4b 58 b9 b1 95 7a
                8b ab cd 23 af 85 4f 4c 35 6f b1 66 2a a7 2b fc
                c7 e5 86 55 9d c4 28 0d 16 0c 12 67 85 a7 23 eb
                ee be ff 71 f1 15 94 44 0a ae f8 7d 10 79 3a 87
                74 a2 39 d4 a0 4c 87 fe 14 67 b9 da f8 52 08 ec
                6c 72 55 79 4a 96 cc 29 14 2f 9a 8b d4 18 e3 c1
                fd 67 34 4b 0c d0 82 9d f3 b2 be c6 02 53 19 62
                93 c6 b3 4d 3f 75 d3 2f 21 3d d4 5c 62 73 d5 05
                ad f4 cc ed 10 57 cb 75 8f c2 6a ee fa 44 12 55
                ed 4e 64 c1 99 ee 07 5e 7f 16 64 61 82 fd b4 64
                73 9b 68 ab 5d af f0 e6 3e 95 52 01 68 24 f0 54
                bf 4d 3c 8c 90 a9 7b b6 b6 55 32 84 eb 42 9f cc''',
                # Random
                '''47 e1 ab 71 19 fe e5 6c 95 ee 5e aa d8 6f 40 d0
                aa 63 bd 33''',
                SHA1
               ),
        )

        def testEncrypt1(self):
                # Verify encryption using all test vectors
                for test in self._testData:
                        # Build the key
                        comps = [ int(rws(test[0][x]),16) for x in ('n','e') ]
                        key = RSA.construct(comps)
                        # RNG that takes its random numbers from a pool given
                        # at initialization
                        class randGen:
                            def __init__(self, data):
                                self.data = data
                                self.idx = 0
                            def __call__(self, N):
                                r = self.data[self.idx:N]
                                self.idx += N
                                return r
                        # The real test
                        cipher = PKCS.new(key, test[4], randfunc=randGen(t2b(test[3])))
                        ct = cipher.encrypt(t2b(test[1]))
                        self.assertEqual(ct, t2b(test[2]))

        def testEncrypt2(self):
                # Verify that encryption fails if plaintext is too long
                pt = '\x00'*(128-2*20-2+1)
                cipher = PKCS.new(self.key1024)
                self.assertRaises(ValueError, cipher.encrypt, pt)

        def testDecrypt1(self):
                # Verify decryption using all test vectors
                for test in self._testData:
                        # Build the key
                        comps = [ int(rws(test[0][x]),16) for x in ('n','e','d') ]
                        key = RSA.construct(comps)
                        # The real test
                        cipher = PKCS.new(key, test[4])
                        pt = cipher.decrypt(t2b(test[2]))
                        self.assertEqual(pt, t2b(test[1]))

        def testDecrypt2(self):
                # Simplest possible negative tests
                for ct_size in (127,128,129):
                    cipher = PKCS.new(self.key1024)
                    self.assertRaises(ValueError, cipher.decrypt, bchr(0x00)*ct_size)

        def testEncryptDecrypt1(self):
                # Encrypt/Decrypt messages of length [0..128-2*20-2]
                for pt_len in range(0,128-2*20-2):
                    pt = self.rng(pt_len)
                    cipher = PKCS.new(self.key1024)
                    ct = cipher.encrypt(pt)
                    pt2 = cipher.decrypt(ct)
                    self.assertEqual(pt,pt2)

        def testEncryptDecrypt2(self):
                # Helper function to monitor what's requested from RNG
                global asked
                def localRng(N):
                    global asked
                    asked += N
                    return self.rng(N)
                # Verify that OAEP is friendly to all hashes
                for hashmod in (MD2,MD5,SHA1,SHA256,RIPEMD160):
                    # Verify that encrypt() asks for as many random bytes
                    # as the hash output size
                    asked = 0
                    pt = self.rng(40)
                    cipher = PKCS.new(self.key1024, hashmod, randfunc=localRng)
                    ct = cipher.encrypt(pt)
                    self.assertEqual(cipher.decrypt(ct), pt)
                    self.assertEqual(asked, hashmod.digest_size)

        def testEncryptDecrypt3(self):
                # Verify that OAEP supports labels
                pt = self.rng(35)
                xlabel = self.rng(22)
                cipher = PKCS.new(self.key1024, label=xlabel)
                ct = cipher.encrypt(pt)
                self.assertEqual(cipher.decrypt(ct), pt)

        def testEncryptDecrypt4(self):
                # Verify that encrypt() uses the custom MGF
                global mgfcalls