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Which key pairing is used for confidentiality?
Symmetric key cryptography also may be used for file encryptions. Public Key cryptography technique uses a pair of keys called private and public. This is used for not only confidentiality of message but also for non-repudiation and user authentication.
Is where the attacker determines the user’s private key?
Total break: THe attacker determines the user’s private key. Universal forgery: The attacker finds an efficient signing algorithm that provides an equivalent way of constructing signatures on arbitrary messages. Selective forgery: The attacker forges a signature for a particular message chosen by the attacker.
How to encrypt data with secret key and IV?
Encrypt the data with your secret key and IV from step 2 (CBC or CTR mode – CTR is better) and update the record. Step two may be performed by taking the IV from previous record and encrypting it with the same secret key – AES’s properties will make this an effectively random IV.
When do I need to use the IV key?
When your application needs to work with the data, the IV is included in the data row which can be used in conjunction with the private key to decrypt the data for use in the software. Finally you need to protect your secret key.
Why does the IV need to be kept secret?
The IV does not need to be kept as secret as the key, the only thing it serves to do is to make sure two of the exact same blobs encrypted with the same key produce two outputs that are totally different from each other (so you can’t tell the same message was sent twice). Many encryption systems just make the IV the first bytes of the message.
How to securely handle AES ” key ” and ” IV ” values?
IV must be “indistinguishable from random” and unpredictable, preferably it must come from the same source as your AES keys; other option is to encrypt some value (different for each record) with a secret key. Encrypt the data with your secret key and IV from step 2 (CBC or CTR mode – CTR is better) and update the record.