Module BSV::Primitives::ECIES ¶

Elliptic Curve Integrated Encryption Scheme (ECIES) using the Electrum/BIE1 protocol.

Provides authenticated encryption using an ephemeral ECDH shared secret. The sender generates a random key pair, derives a shared secret with the recipient's public key, then encrypts with AES-128-CBC and authenticates with HMAC-SHA-256 (encrypt-then-MAC).

@example Encrypt and decrypt a message

alice = BSV::Primitives::PrivateKey.generate
bob   = BSV::Primitives::PrivateKey.generate

ciphertext = BSV::Primitives::ECIES.encrypt('hello', bob.public_key)
plaintext  = BSV::Primitives::ECIES.decrypt(ciphertext, bob)

Constants¶

MAGIC ¶

BIE1 magic bytes identifying the Electrum ECIES format.

Public Class Methods¶

decrypt(data, private_key) ¶

Decrypt an ECIES-encrypted message with a private key.

Verifies the HMAC before attempting decryption (encrypt-then-MAC). - @param data [String] the encrypted payload (BIE1 format) - @param private_key [PrivateKey] the recipient's private key - @raise [ArgumentError] if the data is too short or has invalid magic bytes - @raise [DecryptionError] if HMAC verification or AES decryption fails - @return [String] the decrypted plaintext

encrypt(message, public_key, private_key: = nil) ¶

Encrypt a message for a recipient's public key. - @param message [String] the plaintext message - @param public_key [PublicKey] the recipient's public key - @param private_key [PrivateKey, nil] optional ephemeral key (random if omitted) - @return [String] encrypted payload: BIE1 magic + ephemeral pubkey + ciphertext + HMAC