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Diffstat (limited to 'docs/primitives/symmetric-encryption.rst')
| -rw-r--r-- | docs/primitives/symmetric-encryption.rst | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/docs/primitives/symmetric-encryption.rst b/docs/primitives/symmetric-encryption.rst index c4bbf0a5..7899e67d 100644 --- a/docs/primitives/symmetric-encryption.rst +++ b/docs/primitives/symmetric-encryption.rst @@ -77,6 +77,25 @@ Modes reuse an ``initialization_vector`` with a given ``key``. + +.. class:: cryptography.primitives.block.modes.CTR(nonce) + + .. warning:: + + Counter mode is not recommended for use with block ciphers that have a + block size of less than 128-bits. + + CTR (Counter) is a mode of operation for block ciphers. It is considered + cryptographically strong. + + :param bytes nonce: Should be random bytes. It is critical to never reuse a + ``nonce`` with a given key. Any reuse of a nonce + with the same key compromises the security of every + message encrypted with that key. Must be the same + number of bytes as the ``block_size`` of the cipher + with a given key. The nonce does not need to be kept + secret and may be included alongside the ciphertext. + .. class:: cryptography.primitives.block.modes.OFB(initialization_vector) OFB (Output Feedback) is a mode of operation for block ciphers. It |