o n~b*@sddlmZddlmZddlmZmZmZmZm Z m Z m Z m Z m Z eddZddZGdd d eZd d Zd d ZdZdZdS))get_random_bytes) _copy_bytes) load_pycryptodome_raw_libcreate_string_bufferget_raw_buffer VoidPointer SmartPointerc_size_t c_uint8_ptrc_ulongis_writeable_bufferzCryptodome.Cipher._chacha20a int chacha20_init(void **pState, const uint8_t *key, size_t keySize, const uint8_t *nonce, size_t nonceSize); int chacha20_destroy(void *state); int chacha20_encrypt(void *state, const uint8_t in[], uint8_t out[], size_t len); int chacha20_seek(void *state, unsigned long block_high, unsigned long block_low, unsigned offset); int hchacha20( const uint8_t key[32], const uint8_t nonce16[16], uint8_t subkey[32]); cCsVt|dksJt|dksJtd}tt|t|t|}|r)td||S)N z,Error %d when deriving subkey with HChaCha20)len bytearray_raw_chacha20_libZ hchacha20r ValueError)keynoncesubkeyresultrE/usr/local/lib/python3.10/dist-packages/Cryptodome/Cipher/ChaCha20.py _HChaCha20Bs rc@s@eZdZdZdZddZdddZdd Zdd d Zd d Z dS)ChaCha20CipherzChaCha20 (or XChaCha20) cipher object. Do not create it directly. Use :py:func:`new` instead. :var nonce: The nonce with length 8, 12 or 24 bytes :vartype nonce: bytes c Cstdd||_t|dkr"t||dd}d|dd}d|_nd|_|j}|j|jf|_t|_ t |j t |tt||tt|}|rTtd||jft|j t j|_ dS)z\Initialize a ChaCha20/XChaCha20 cipher object See also `new()` at the module level.NrZ XChaCha20ZChaCha20z"Error %d instantiating a %s cipher)rrrr_nameencryptdecrypt_nextr_staterZ chacha20_initZ address_ofr r rrgetZchacha20_destroy)selfrrrrrr__init__\s.     zChaCha20Cipher.__init__NcCs*|j|jvr td|jf|_|||S)aEncrypt a piece of data. Args: plaintext(bytes/bytearray/memoryview): The data to encrypt, of any size. Keyword Args: output(bytes/bytearray/memoryview): The location where the ciphertext is written to. If ``None``, the ciphertext is returned. Returns: If ``output`` is ``None``, the ciphertext is returned as ``bytes``. Otherwise, ``None``. z-Cipher object can only be used for decryption)rr! TypeError_encrypt)r$ plaintextoutputrrrr|s   zChaCha20Cipher.encryptcCs|dur tt|}n|}t|stdt|t|kr%tdt|t|jt |t |t t|}|rCtd||j f|durKt |SdS)zEncrypt without FSM checksNz4output must be a bytearray or a writeable memoryviewz9output must have the same length as the input (%d bytes)z!Error %d while encrypting with %s) rrr r&rrZchacha20_encryptr"r#r r rr)r$r(r) ciphertextrrrrr's( zChaCha20Cipher._encryptc CsZ|j|jvr td|jf|_z|||WSty,}z tt|ddd}~ww)aDecrypt a piece of data. Args: ciphertext(bytes/bytearray/memoryview): The data to decrypt, of any size. Keyword Args: output(bytes/bytearray/memoryview): The location where the plaintext is written to. If ``None``, the plaintext is returned. Returns: If ``output`` is ``None``, the plaintext is returned as ``bytes``. Otherwise, ``None``. z-Cipher object can only be used for encryptionencdecN)r r!r&r'rstrreplace)r$r*r)errrr s  zChaCha20Cipher.decryptcCsVt|d\}}|d@}|d?}t|jt|t||}|r)td||jfdS)zSeek to a certain position in the key stream. Args: position (integer): The absolute position within the key stream, in bytes. @lr zError %d while seeking with %sN)divmodrZ chacha20_seekr"r#r rr)r$positionoffsetZ block_lowZ block_highrrrrseekszChaCha20Cipher.seek)N) __name__ __module__ __qualname____doc__ block_sizer%rr'r r4rrrrrRs   rcCst|dkr td|durtd}}nt|dkr d|}n t|dkr)|}ntdt||dd }|dd |d d|fS) zrDerive a tuple (r, s, nonce) for a Poly1305 MAC. If nonce is ``None``, a new 12-byte nonce is generated. r z-Poly1305 with ChaCha20 requires a 32-byte keyN rz6Poly1305 with ChaCha20 requires an 8- or 12-byte nonce)rrs r)rrrnewr)rrZ padded_noncersrrr_derive_Poly1305_key_pairs    r>c Ksz|d}Wnty}ztd|d}~ww|dd}|dur(td}t|dkr2tdt|dvrr<r9Zkey_sizerrrrs  ,)