In pyca/cryptography, one uses the AES() class and gets AES-128 or AES-256 depending on the key size: https://cryptography.io/en/latest/hazmat/primitives/symmetric-encryption/#cryptography.hazmat.primitives.ciphers.algorithms.AES
You can also use the AES128 and AES256 types explicitly if you prefer. Alex On Thu, Feb 2, 2023 at 8:14 PM Arshad Khan <khan.m.ars...@gmail.com> wrote: > > Thanks Alex for the quick reply. > > So in my case it can be said that I am using AES-256-CTR cipher? Because I > was calling it AES-128-CTR and people were asking me why I am using a smaller > key. > > On Fri, Feb 3, 2023 at 9:09 AM Alex Gaynor <alex.gay...@gmail.com> wrote: >> >> This is not correct, block size and key size are not the same thing >> for symmetric encryption algorithms. >> >> AES's block size is always 128-bit, it's not something cryptography >> chooses to use, it's the definition of the algorithm. >> >> Alex >> >> On Thu, Feb 2, 2023 at 8:02 PM Arshad Khan <khan.m.ars...@gmail.com> wrote: >> > >> > Hello >> > >> > I have a question regarding AES in python cryptography which uses a block >> > size of 128 bits. Currently I am using 256 bit keys with AES in CTR mode. >> > However, internally the python cryptography uses a block size of 128. My >> > understanding is that block size and key size are the same for symmetric >> > encryption. How does a 256 bits key work in this case? Appreciate if >> > someone could provide some explanation about this and clear my confusion. >> > >> > Thanks >> > Arshad >> > _______________________________________________ >> > Cryptography-dev mailing list >> > Cryptography-dev@python.org >> > https://mail.python.org/mailman/listinfo/cryptography-dev >> >> >> >> -- >> All that is necessary for evil to succeed is for good people to do nothing. >> _______________________________________________ >> Cryptography-dev mailing list >> Cryptography-dev@python.org >> https://mail.python.org/mailman/listinfo/cryptography-dev > > _______________________________________________ > Cryptography-dev mailing list > Cryptography-dev@python.org > https://mail.python.org/mailman/listinfo/cryptography-dev -- All that is necessary for evil to succeed is for good people to do nothing. _______________________________________________ Cryptography-dev mailing list Cryptography-dev@python.org https://mail.python.org/mailman/listinfo/cryptography-dev
