Google: Maintaining digital certificate security

Posted Mar 25, 2015 22:20 UTC (Wed) by Cyberax (✭ supporter ✭, #52523)
In reply to: Google: Maintaining digital certificate security by tialaramex
Parent article: Google: Maintaining digital certificate security

AES-CTR and AES-GCM work perfectly fine on unpadded data. Even with the good old AES-CBC you can simply omit padding bytes from the wire protocol.

Google: Maintaining digital certificate security

Posted Mar 25, 2015 23:29 UTC (Wed) by cesarb (subscriber, #6266) [Link] (1 responses)

AFAIK, to "omit" padding on CBC one has to do ciphertext stealing. You can't simply "omit padding bytes", a block cipher mixes a block throughly so that if even one bit of ciphertext is changed or lost, that block once decrypted is garbage.

Google: Maintaining digital certificate security

Posted Mar 26, 2015 6:18 UTC (Thu) by Cyberax (✭ supporter ✭, #52523) [Link]

Yes, you're certainly right. My bad. I used ciphers in block mode too long ago.