,h'|dZdgZddlmZddlmZmZmZmZm Z m Z m Z m Z ddl mZeddZGddeZd Zy ) z Output Feedback (CFB) mode. OfbMode) _copy_bytes)load_pycryptodome_raw_lib VoidPointercreate_string_bufferget_raw_buffer SmartPointerc_size_t c_uint8_ptris_writeable_buffer)get_random_byteszCrypto.Cipher._raw_ofba int OFB_start_operation(void *cipher, const uint8_t iv[], size_t iv_len, void **pResult); int OFB_encrypt(void *ofbState, const uint8_t *in, uint8_t *out, size_t data_len); int OFB_decrypt(void *ofbState, const uint8_t *in, uint8_t *out, size_t data_len); int OFB_stop_operation(void *state); c&eZdZdZdZddZddZy)ra*Output FeedBack (OFB)*. This mode is very similar to CBC, but it transforms the underlying block cipher into a stream cipher. The keystream is the iterated block encryption of the previous ciphertext block. An Initialization Vector (*IV*) is required. See `NIST SP800-38A`_ , Section 6.4. .. _`NIST SP800-38A` : http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf :undocumented: __init__ c t|_tj|j t |t t||jj}|rtd|zt|jj tj|_|jt||_ tdd||_ |j|_ ddg|_y)aSCreate a new block cipher, configured in OFB mode. :Parameters: block_cipher : C pointer A smart pointer to the low-level block cipher instance. iv : bytes/bytearray/memoryview The initialization vector to use for encryption or decryption. It is as long as the cipher block. **The IV must be a nonce, to to be reused for any other message**. It shall be a nonce or a random value. Reusing the *IV* for encryptions performed with the same key compromises confidentiality. z)Error %d while instantiating the OFB modeNencryptdecrypt)r_state raw_ofb_libOFB_start_operationgetr r len address_of ValueErrorr OFB_stop_operationrelease block_sizerivIV_next)self block_cipherrresults Y/var/www/html/Resume-Scraper/venv/lib/python3.12/site-packages/Crypto/Cipher/_mode_ofb.py__init__zOfbMode.__init__Is$"m 001A1A1C1>> c.encrypt(a) + c.encrypt(b) is equivalent to: >>> c.encrypt(a+b) This function does not add any padding to the plaintext. :Parameters: plaintext : bytes/bytearray/memoryview The piece of data to encrypt. It can be of any length. :Keywords: output : bytearray/memoryview The location where the ciphertext must be written to. If ``None``, the ciphertext is returned. :Return: If ``output`` is ``None``, the ciphertext is returned as ``bytes``. Otherwise, ``None``. rz*encrypt() cannot be called after decrypt()N4output must be a bytearray or a writeable memoryview9output must have the same length as the input (%d bytes)z%Error %d while encrypting in OFB mode) r TypeErrorrrr rr OFB_encryptrrr r r)r plaintextoutput ciphertextr!s r"rzOfbMode.encryptysB DJJ &HI I[ >-c)n=JJ&v. VWW9~V, "025i."ABB(():)4Y)?)4Z)@)1#i.)AC DvMN N >!*- -r$c d|jvr tddg|_|tt|}nF|}t |s tdt|t|k7rt dt|zt j|jjt|t|tt|}|rt d|z| t|Sy)aDecrypt data with the key and the parameters set at initialization. A cipher object is stateful: once you have decrypted a message you cannot decrypt (or encrypt) another message with the same object. The data to decrypt can be broken up in two or more pieces and `decrypt` can be called multiple times. That is, the statement: >>> c.decrypt(a) + c.decrypt(b) is equivalent to: >>> c.decrypt(a+b) This function does not remove any padding from the plaintext. :Parameters: ciphertext : bytes/bytearray/memoryview The piece of data to decrypt. It can be of any length. :Keywords: output : bytearray/memoryview The location where the plaintext is written to. If ``None``, the plaintext is returned. :Return: If ``output`` is ``None``, the plaintext is returned as ``bytes``. Otherwise, ``None``. rz*decrypt() cannot be called after encrypt()Nr&r'z%Error %d while decrypting in OFB mode) rr(rrr rr OFB_decryptrrr r r)rr,r+r*r!s r"rzOfbMode.decryptsB DJJ &HI I[ >,S_=II&v. VWW:#f+- "025i."ABB(():)4Z)@)4Y)?)1#j/)BD DvMN N >!), ,r$)N)__name__ __module__ __qualname____doc__r#rrr$r"rr7s".,`;z;r$c p|j|}|jdd}|jdd}d||fk(rt|j}| | t d|}t ||jk7rt d|jz|rt dt|zt||S)aInstantiate a cipher object that performs OFB encryption/decryption. :Parameters: factory : module The underlying block cipher, a module from ``Crypto.Cipher``. :Keywords: iv : bytes/bytearray/memoryview The IV to use for OFB. IV : bytes/bytearray/memoryview Alias for ``iv``. Any other keyword will be passed to the underlying block cipher. See the relevant documentation for details (at least ``key`` will need to be present). rNr)NNz*You must either use 'iv' or 'IV', not bothz.Incorrect IV length (it must be %d bytes long)zUnknown parameters for OFB: %s) _create_base_cipherpopr rr(rrstrr)factorykwargs cipher_staterrs r"_create_ofb_cipherr;s&..v6L D$ B D$ BBx g00 1 ~ >HI I  2w'$$$I""#$ $83v;FGG < $$r$N)r2__all__Crypto.Util.py3compatrCrypto.Util._raw_apirrrrr r r r Crypto.Randomr robjectrr;r3r$r"rAsQ. +-777 +'(@C* $zfzz&%r$