![]() ![]() If you're looking to just encrypt some data, you should use the Encrypt family of actions. If the salt was unique per encryption you couldn't bulk process anything since you couldn't pre-process the key. This is also one of the reasons why key derivation uses a fixed salt. If you want to process a lot of data with the same key, you can use the K* version of the actions to avoid deriving the key for each encryption/mac. NET framework crypto library or from bouncy castle (in Java).ĭata (strings) are utf-8 encoded prior to encryption and utf-8 decoded upon decryption. Key derivation (DeriveKey action): RFC 2898 PBKDF2 with fixed 128 byte salt using HMACSha1 as the underlying mac algorithm with 37649 iterations.Īll crypto implementations are taken from either. Integrity schema (ComputeMac action): HMACSHA256 with 256 bit key. Ciphertext is Base64Encode( MSB(128, mac(k, plaintext)) || E(iv, k, plaintext) ) where MSB(b, v) stands for the b most significant bits (left-most) of v.Īsymmetric encryption schema uses RSA with OAEP padding with the common MFG1 and SHA1 functions as parameters. I use the same key for confidentiality and integrity. Ciphertext is Base64Encode(iv || E(iv,k,plaintext) || mac(k, iv || E(iv,k,plaintext))ĭeterministic encryption schema (Det_Encrypt/Det_Decrypt Actions): AES with 256 bit key in CBC mode with PKCS7 padding and Synthetic Initialization vector taken from the first 16 bytes of the HMACSHA256 mac of the plaintext. Randomized encryption schema (Encrypt/Decrypt Actions): AES with 256 bit key in CBC mode with PKCS7 padding and randomized Initialization Vector + HMACSHA256 for integrity. Both of them provide authenticated encryption, meaning they'll let you know if the ciphertext has been tampered with. One for randomized encryption and another for deterministic encryption. In this extension I have two encryption schemas. It is not Chosen Plaintext secure, which basically means it's possible to tell when ciphertexts relate to the same plaintext (with the same key), which leaks some information.Ģ) It uses custom implementations of some of the cryptographic primitives, which is generally a bad practice.ģ) It does not use an authenticated encryption schema which means that your data may be tampered without you realizing it.įor reference, the EM Crypto extension uses AES in CBC mode with PKCS7 padding with fixed Initialization Vector. The key derivation for EM Crypto, for interoperability reasons, has custom code in the Java version. There are a couple of problems I found with the EnterpriseManager Crypto extension:ġ) the encryption scheme used is relatively weak by today's standards. Some of you may be asking why I made this component, since Enterprise Manager already provides a Crypto library. ![]()
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