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segment_size
is the number of bits
plaintext
and
ciphertext
are segmented in. Is
only used in AES.MODE_CFB. Supported values are AES.SEGMENT_8 and
AES.SEGMENT_128.
Methods
ucrypto.encrypt()
Encrypt data with the key and the parameters set at initialisation.
ucrypto.decrypt()
Decrypt data with the key and the parameters set at initialisation.
Constants
AES.MODE_ECB
Electronic Code Book. Simplest encryption mode. It does not hide data patterns well (see
this article for more info).
AES.MODE_CBC
Cipher-Block Chaining. An Initialisation Vector (IV) is required.
AES.MODE_CFB
Cipher feedback.
plaintext
and
ciphertext
are processed in segments of
segment_size
bits. Works a stream cipher.
AES.MODE_CTR
Counter mode. Each message block is associated to a counter which must be unique across
all messages that get encrypted with the same key.
AES.SEGMENT_8 AES.SEGMENT_128
Length of the segment for AES.MODE_CFB.
To avoid security issues, IV should always be a random number and should never be
reused to encrypt two different messages. The same applies to the counter in CTR
mode. You can use crypto.getrandbits() for this purpose.
5.2.3 AES
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