Simple Free Encryption Tool
Simple Free Encryption Tool (sfet)
uses RSA and AES versions that are strong and allow
Open and free for all to see, can be run stand-alone for extra security,
If you've found this tool useful,
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RSA encryption operates on a very limited string length, it is generally used to asymmetrically
encrypt a shared secret that in turn is used for symmetric encryption. The standard use-case is
to generate a random shared secret and transmit it encrypted with the destination's public RSA
key. Once the destination has decrypted the shared secret with its private RSA key both sides
will be able to use that secret to encrypt and decrypt communication with AES.
Signing a message to prove authorship (and that it hasn't been tampered with) is performed on
the plaintext message, and the resulting signature can only be verified with the public key
matching the private key it was signed with. The padding for signing and verifying signatures
is not the same as for encrypting and decrypting messages.
The AES secret must be a 32 character string. In order to ensure a valid string, the secret is
hashed using the MD5 algorithm to produce a string of the correct length.
The IV, or Initialization Vector, is a 16 character hexadecimal string that's required by the AES algorithm
(read this for a detailed explanation
It's not really necessary when encryption secrets aren't being reused, but as it's enforced by
the underlying crypto package it's recommended to include it. If you do choose to leave it out,
a default IV of '0000000000000000' will be used.
Signing messages and verifying signatures with simple-free-encryption-tool are performed using the SHA-256
If your browser supports it, you will be able to encrypt and decrypt files from this interface.
The file metadata (eg. MIME type) will not be encrypted, only the file contents.