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Raphaƫl G. Git Repositories - youtubedl/blob - youtube_dl/aes.py
1 from __future__
import unicode_literals
5 from .compat
import compat_b64decode
6 from .utils
import bytes_to_intlist
, intlist_to_bytes
11 def aes_ctr_decrypt(data
, key
, counter
):
13 Decrypt with aes in counter mode
15 @param {int[]} data cipher
16 @param {int[]} key 16/24/32-Byte cipher key
17 @param {instance} counter Instance whose next_value function (@returns {int[]} 16-Byte block)
18 returns the next counter block
19 @returns {int[]} decrypted data
21 expanded_key
= key_expansion(key
)
22 block_count
= int(ceil(float(len(data
)) / BLOCK_SIZE_BYTES
))
25 for i
in range(block_count
):
26 counter_block
= counter
.next_value()
27 block
= data
[i
* BLOCK_SIZE_BYTES
: (i
+ 1) * BLOCK_SIZE_BYTES
]
28 block
+= [0] * (BLOCK_SIZE_BYTES
- len(block
))
30 cipher_counter_block
= aes_encrypt(counter_block
, expanded_key
)
31 decrypted_data
+= xor(block
, cipher_counter_block
)
32 decrypted_data
= decrypted_data
[:len(data
)]
37 def aes_cbc_decrypt(data
, key
, iv
):
39 Decrypt with aes in CBC mode
41 @param {int[]} data cipher
42 @param {int[]} key 16/24/32-Byte cipher key
43 @param {int[]} iv 16-Byte IV
44 @returns {int[]} decrypted data
46 expanded_key
= key_expansion(key
)
47 block_count
= int(ceil(float(len(data
)) / BLOCK_SIZE_BYTES
))
50 previous_cipher_block
= iv
51 for i
in range(block_count
):
52 block
= data
[i
* BLOCK_SIZE_BYTES
: (i
+ 1) * BLOCK_SIZE_BYTES
]
53 block
+= [0] * (BLOCK_SIZE_BYTES
- len(block
))
55 decrypted_block
= aes_decrypt(block
, expanded_key
)
56 decrypted_data
+= xor(decrypted_block
, previous_cipher_block
)
57 previous_cipher_block
= block
58 decrypted_data
= decrypted_data
[:len(data
)]
63 def aes_cbc_encrypt(data
, key
, iv
):
65 Encrypt with aes in CBC mode. Using PKCS#7 padding
67 @param {int[]} data cleartext
68 @param {int[]} key 16/24/32-Byte cipher key
69 @param {int[]} iv 16-Byte IV
70 @returns {int[]} encrypted data
72 expanded_key
= key_expansion(key
)
73 block_count
= int(ceil(float(len(data
)) / BLOCK_SIZE_BYTES
))
76 previous_cipher_block
= iv
77 for i
in range(block_count
):
78 block
= data
[i
* BLOCK_SIZE_BYTES
: (i
+ 1) * BLOCK_SIZE_BYTES
]
79 remaining_length
= BLOCK_SIZE_BYTES
- len(block
)
80 block
+= [remaining_length
] * remaining_length
81 mixed_block
= xor(block
, previous_cipher_block
)
83 encrypted_block
= aes_encrypt(mixed_block
, expanded_key
)
84 encrypted_data
+= encrypted_block
86 previous_cipher_block
= encrypted_block
91 def key_expansion(data
):
95 @param {int[]} data 16/24/32-Byte cipher key
96 @returns {int[]} 176/208/240-Byte expanded key
100 key_size_bytes
= len(data
)
101 expanded_key_size_bytes
= (key_size_bytes
// 4 + 7) * BLOCK_SIZE_BYTES
103 while len(data
) < expanded_key_size_bytes
:
105 temp
= key_schedule_core(temp
, rcon_iteration
)
107 data
+= xor(temp
, data
[-key_size_bytes
: 4 - key_size_bytes
])
111 data
+= xor(temp
, data
[-key_size_bytes
: 4 - key_size_bytes
])
113 if key_size_bytes
== 32:
115 temp
= sub_bytes(temp
)
116 data
+= xor(temp
, data
[-key_size_bytes
: 4 - key_size_bytes
])
118 for _
in range(3 if key_size_bytes
== 32 else 2 if key_size_bytes
== 24 else 0):
120 data
+= xor(temp
, data
[-key_size_bytes
: 4 - key_size_bytes
])
121 data
= data
[:expanded_key_size_bytes
]
126 def aes_encrypt(data
, expanded_key
):
128 Encrypt one block with aes
130 @param {int[]} data 16-Byte state
131 @param {int[]} expanded_key 176/208/240-Byte expanded key
132 @returns {int[]} 16-Byte cipher
134 rounds
= len(expanded_key
) // BLOCK_SIZE_BYTES
- 1
136 data
= xor(data
, expanded_key
[:BLOCK_SIZE_BYTES
])
137 for i
in range(1, rounds
+ 1):
138 data
= sub_bytes(data
)
139 data
= shift_rows(data
)
141 data
= mix_columns(data
)
142 data
= xor(data
, expanded_key
[i
* BLOCK_SIZE_BYTES
: (i
+ 1) * BLOCK_SIZE_BYTES
])
147 def aes_decrypt(data
, expanded_key
):
149 Decrypt one block with aes
151 @param {int[]} data 16-Byte cipher
152 @param {int[]} expanded_key 176/208/240-Byte expanded key
153 @returns {int[]} 16-Byte state
155 rounds
= len(expanded_key
) // BLOCK_SIZE_BYTES
- 1
157 for i
in range(rounds
, 0, -1):
158 data
= xor(data
, expanded_key
[i
* BLOCK_SIZE_BYTES
: (i
+ 1) * BLOCK_SIZE_BYTES
])
160 data
= mix_columns_inv(data
)
161 data
= shift_rows_inv(data
)
162 data
= sub_bytes_inv(data
)
163 data
= xor(data
, expanded_key
[:BLOCK_SIZE_BYTES
])
168 def aes_decrypt_text(data
, password
, key_size_bytes
):
171 - The first 8 Bytes of decoded 'data' are the 8 high Bytes of the counter
172 - The cipher key is retrieved by encrypting the first 16 Byte of 'password'
173 with the first 'key_size_bytes' Bytes from 'password' (if necessary filled with 0's)
174 - Mode of operation is 'counter'
176 @param {str} data Base64 encoded string
177 @param {str,unicode} password Password (will be encoded with utf-8)
178 @param {int} key_size_bytes Possible values: 16 for 128-Bit, 24 for 192-Bit or 32 for 256-Bit
179 @returns {str} Decrypted data
181 NONCE_LENGTH_BYTES
= 8
183 data
= bytes_to_intlist(compat_b64decode(data
))
184 password
= bytes_to_intlist(password
.encode('utf-8'))
186 key
= password
[:key_size_bytes
] + [0] * (key_size_bytes
- len(password
))
187 key
= aes_encrypt(key
[:BLOCK_SIZE_BYTES
], key_expansion(key
)) * (key_size_bytes
// BLOCK_SIZE_BYTES
)
189 nonce
= data
[:NONCE_LENGTH_BYTES
]
190 cipher
= data
[NONCE_LENGTH_BYTES
:]
192 class Counter(object):
193 __value
= nonce
+ [0] * (BLOCK_SIZE_BYTES
- NONCE_LENGTH_BYTES
)
195 def next_value(self
):
197 self
.__value
= inc(self
.__value
)
200 decrypted_data
= aes_ctr_decrypt(cipher
, key
, Counter())
201 plaintext
= intlist_to_bytes(decrypted_data
)
206 RCON
= (0x8d, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36)
207 SBOX
= (0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76,
208 0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0, 0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0,
209 0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC, 0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15,
210 0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 0x07, 0x12, 0x80, 0xE2, 0xEB, 0x27, 0xB2, 0x75,
211 0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0, 0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84,
212 0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B, 0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF,
213 0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85, 0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8,
214 0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5, 0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2,
215 0xCD, 0x0C, 0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17, 0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73,
216 0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88, 0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB,
217 0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79,
218 0xE7, 0xC8, 0x37, 0x6D, 0x8D, 0xD5, 0x4E, 0xA9, 0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08,
219 0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A,
220 0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E,
221 0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9, 0x8E, 0x94, 0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF,
222 0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16)
223 SBOX_INV
= (0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
224 0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
225 0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
226 0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
227 0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
228 0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
229 0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
230 0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
231 0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
232 0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
233 0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
234 0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
235 0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
236 0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
237 0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
238 0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d)
239 MIX_COLUMN_MATRIX
= ((0x2, 0x3, 0x1, 0x1),
240 (0x1, 0x2, 0x3, 0x1),
241 (0x1, 0x1, 0x2, 0x3),
242 (0x3, 0x1, 0x1, 0x2))
243 MIX_COLUMN_MATRIX_INV
= ((0xE, 0xB, 0xD, 0x9),
244 (0x9, 0xE, 0xB, 0xD),
245 (0xD, 0x9, 0xE, 0xB),
246 (0xB, 0xD, 0x9, 0xE))
247 RIJNDAEL_EXP_TABLE
= (0x01, 0x03, 0x05, 0x0F, 0x11, 0x33, 0x55, 0xFF, 0x1A, 0x2E, 0x72, 0x96, 0xA1, 0xF8, 0x13, 0x35,
248 0x5F, 0xE1, 0x38, 0x48, 0xD8, 0x73, 0x95, 0xA4, 0xF7, 0x02, 0x06, 0x0A, 0x1E, 0x22, 0x66, 0xAA,
249 0xE5, 0x34, 0x5C, 0xE4, 0x37, 0x59, 0xEB, 0x26, 0x6A, 0xBE, 0xD9, 0x70, 0x90, 0xAB, 0xE6, 0x31,
250 0x53, 0xF5, 0x04, 0x0C, 0x14, 0x3C, 0x44, 0xCC, 0x4F, 0xD1, 0x68, 0xB8, 0xD3, 0x6E, 0xB2, 0xCD,
251 0x4C, 0xD4, 0x67, 0xA9, 0xE0, 0x3B, 0x4D, 0xD7, 0x62, 0xA6, 0xF1, 0x08, 0x18, 0x28, 0x78, 0x88,
252 0x83, 0x9E, 0xB9, 0xD0, 0x6B, 0xBD, 0xDC, 0x7F, 0x81, 0x98, 0xB3, 0xCE, 0x49, 0xDB, 0x76, 0x9A,
253 0xB5, 0xC4, 0x57, 0xF9, 0x10, 0x30, 0x50, 0xF0, 0x0B, 0x1D, 0x27, 0x69, 0xBB, 0xD6, 0x61, 0xA3,
254 0xFE, 0x19, 0x2B, 0x7D, 0x87, 0x92, 0xAD, 0xEC, 0x2F, 0x71, 0x93, 0xAE, 0xE9, 0x20, 0x60, 0xA0,
255 0xFB, 0x16, 0x3A, 0x4E, 0xD2, 0x6D, 0xB7, 0xC2, 0x5D, 0xE7, 0x32, 0x56, 0xFA, 0x15, 0x3F, 0x41,
256 0xC3, 0x5E, 0xE2, 0x3D, 0x47, 0xC9, 0x40, 0xC0, 0x5B, 0xED, 0x2C, 0x74, 0x9C, 0xBF, 0xDA, 0x75,
257 0x9F, 0xBA, 0xD5, 0x64, 0xAC, 0xEF, 0x2A, 0x7E, 0x82, 0x9D, 0xBC, 0xDF, 0x7A, 0x8E, 0x89, 0x80,
258 0x9B, 0xB6, 0xC1, 0x58, 0xE8, 0x23, 0x65, 0xAF, 0xEA, 0x25, 0x6F, 0xB1, 0xC8, 0x43, 0xC5, 0x54,
259 0xFC, 0x1F, 0x21, 0x63, 0xA5, 0xF4, 0x07, 0x09, 0x1B, 0x2D, 0x77, 0x99, 0xB0, 0xCB, 0x46, 0xCA,
260 0x45, 0xCF, 0x4A, 0xDE, 0x79, 0x8B, 0x86, 0x91, 0xA8, 0xE3, 0x3E, 0x42, 0xC6, 0x51, 0xF3, 0x0E,
261 0x12, 0x36, 0x5A, 0xEE, 0x29, 0x7B, 0x8D, 0x8C, 0x8F, 0x8A, 0x85, 0x94, 0xA7, 0xF2, 0x0D, 0x17,
262 0x39, 0x4B, 0xDD, 0x7C, 0x84, 0x97, 0xA2, 0xFD, 0x1C, 0x24, 0x6C, 0xB4, 0xC7, 0x52, 0xF6, 0x01)
263 RIJNDAEL_LOG_TABLE
= (0x00, 0x00, 0x19, 0x01, 0x32, 0x02, 0x1a, 0xc6, 0x4b, 0xc7, 0x1b, 0x68, 0x33, 0xee, 0xdf, 0x03,
264 0x64, 0x04, 0xe0, 0x0e, 0x34, 0x8d, 0x81, 0xef, 0x4c, 0x71, 0x08, 0xc8, 0xf8, 0x69, 0x1c, 0xc1,
265 0x7d, 0xc2, 0x1d, 0xb5, 0xf9, 0xb9, 0x27, 0x6a, 0x4d, 0xe4, 0xa6, 0x72, 0x9a, 0xc9, 0x09, 0x78,
266 0x65, 0x2f, 0x8a, 0x05, 0x21, 0x0f, 0xe1, 0x24, 0x12, 0xf0, 0x82, 0x45, 0x35, 0x93, 0xda, 0x8e,
267 0x96, 0x8f, 0xdb, 0xbd, 0x36, 0xd0, 0xce, 0x94, 0x13, 0x5c, 0xd2, 0xf1, 0x40, 0x46, 0x83, 0x38,
268 0x66, 0xdd, 0xfd, 0x30, 0xbf, 0x06, 0x8b, 0x62, 0xb3, 0x25, 0xe2, 0x98, 0x22, 0x88, 0x91, 0x10,
269 0x7e, 0x6e, 0x48, 0xc3, 0xa3, 0xb6, 0x1e, 0x42, 0x3a, 0x6b, 0x28, 0x54, 0xfa, 0x85, 0x3d, 0xba,
270 0x2b, 0x79, 0x0a, 0x15, 0x9b, 0x9f, 0x5e, 0xca, 0x4e, 0xd4, 0xac, 0xe5, 0xf3, 0x73, 0xa7, 0x57,
271 0xaf, 0x58, 0xa8, 0x50, 0xf4, 0xea, 0xd6, 0x74, 0x4f, 0xae, 0xe9, 0xd5, 0xe7, 0xe6, 0xad, 0xe8,
272 0x2c, 0xd7, 0x75, 0x7a, 0xeb, 0x16, 0x0b, 0xf5, 0x59, 0xcb, 0x5f, 0xb0, 0x9c, 0xa9, 0x51, 0xa0,
273 0x7f, 0x0c, 0xf6, 0x6f, 0x17, 0xc4, 0x49, 0xec, 0xd8, 0x43, 0x1f, 0x2d, 0xa4, 0x76, 0x7b, 0xb7,
274 0xcc, 0xbb, 0x3e, 0x5a, 0xfb, 0x60, 0xb1, 0x86, 0x3b, 0x52, 0xa1, 0x6c, 0xaa, 0x55, 0x29, 0x9d,
275 0x97, 0xb2, 0x87, 0x90, 0x61, 0xbe, 0xdc, 0xfc, 0xbc, 0x95, 0xcf, 0xcd, 0x37, 0x3f, 0x5b, 0xd1,
276 0x53, 0x39, 0x84, 0x3c, 0x41, 0xa2, 0x6d, 0x47, 0x14, 0x2a, 0x9e, 0x5d, 0x56, 0xf2, 0xd3, 0xab,
277 0x44, 0x11, 0x92, 0xd9, 0x23, 0x20, 0x2e, 0x89, 0xb4, 0x7c, 0xb8, 0x26, 0x77, 0x99, 0xe3, 0xa5,
278 0x67, 0x4a, 0xed, 0xde, 0xc5, 0x31, 0xfe, 0x18, 0x0d, 0x63, 0x8c, 0x80, 0xc0, 0xf7, 0x70, 0x07)
282 return [SBOX
[x
] for x
in data
]
285 def sub_bytes_inv(data
):
286 return [SBOX_INV
[x
] for x
in data
]
290 return data
[1:] + [data
[0]]
293 def key_schedule_core(data
, rcon_iteration
):
295 data
= sub_bytes(data
)
296 data
[0] = data
[0] ^ RCON
[rcon_iteration
]
301 def xor(data1
, data2
):
302 return [x ^ y
for x
, y
in zip(data1
, data2
)]
305 def rijndael_mul(a
, b
):
306 if(a
== 0 or b
== 0):
308 return RIJNDAEL_EXP_TABLE
[(RIJNDAEL_LOG_TABLE
[a
] + RIJNDAEL_LOG_TABLE
[b
]) % 0xFF]
311 def mix_column(data
, matrix
):
315 for column
in range(4):
317 mixed ^
= rijndael_mul(data
[column
], matrix
[row
][column
])
318 data_mixed
.append(mixed
)
322 def mix_columns(data
, matrix
=MIX_COLUMN_MATRIX
):
325 column
= data
[i
* 4: (i
+ 1) * 4]
326 data_mixed
+= mix_column(column
, matrix
)
330 def mix_columns_inv(data
):
331 return mix_columns(data
, MIX_COLUMN_MATRIX_INV
)
334 def shift_rows(data
):
336 for column
in range(4):
338 data_shifted
.append(data
[((column
+ row
) & 0b11) * 4 + row
])
342 def shift_rows_inv(data
):
344 for column
in range(4):
346 data_shifted
.append(data
[((column
- row
) & 0b11) * 4 + row
])
351 data
= data
[:] # copy
352 for i
in range(len(data
) - 1, -1, -1):
356 data
[i
] = data
[i
] + 1
361 __all__
= ['aes_encrypt', 'key_expansion', 'aes_ctr_decrypt', 'aes_cbc_decrypt', 'aes_decrypt_text']