support for aes-gcm-siv mode (rfc8452)

[sify21]

I also can't find aes-gcm-siv implementations in other popular python projects like tink and cryptography, only a sample script which was written 3 years ago and clearly states that Do not use .
Related issues: pyca/cryptography#5877 (comment)

[sify21]

the script works fine, just need to change all AES.new(key) to AES.new(key, AES.MODE_ECB )

[tasket]

If the block for this is Openssl upstream, they have recently added AES-GCM-SIV support:
openssl/openssl#16721

[redfast00]

It is implemented in cryptography; see https://cryptography.io/en/latest/hazmat/primitives/aead/#cryptography.hazmat.primitives.ciphers.aead.AESGCMSIV