legacy_encryption

Legacy version of encryption module. Learn more about encryption.

exception human_protocol_sdk.legacy_encryption.DecryptionError

Bases: Exception

Raised when a message could not be decrypted.

class human_protocol_sdk.legacy_encryption.Encryption

Bases: object

Encryption class specialized in encrypting and decrypting a byte string.

CIPHER

Cipher algorithm defintion.

alias of AES

ELLIPTIC_CURVE : EllipticCurve = <cryptography.hazmat.primitives.asymmetric.ec.SECP256K1 object>

Elliptic curve definition.

KEY_LEN = 32

ECIES using AES256 and HMAC-SHA-256-32

MODE

Cipher mode definition.

alias of CTR

PUBLIC_KEY_LEN : int = 64

Length of public keys: 512 bit keys in uncompressed form, without format byte

decrypt(data, private_key, shared_mac_data=b'')

Decrypt data with ECIES method using the given private key

1. generate shared-secret = kdf( ecdhAgree(myPrivKey, msg[1:65]) )

2. verify tag

3. decrypt ecdhAgree(r, recipientPublic) == ecdhAgree(recipientPrivate, R) [where R = r*G, and recipientPublic = recipientPrivate*G]

• Parameters:

  • data (bytes) – Data to be decrypted

  • private_key (PrivateKey) – Private key to be used in agreement.

  • shared_mac_data (bytes) – shared mac additional data as suffix.

• Return type: bytes

• Returns: Decrypted byte string

• Example:

  from human_protocol_sdk.legacy_encryption import Encryption
  from eth_keys import datatypes
  
  private_key_str = "9822f95dd945e373300f8c8459a831846eda97f314689e01f7cf5b8f1c2298b3"
  encrypted_message_str = "0402f48d28d29ae3d681e4cbbe499be0803c2a9d94534d0a4501ab79fd531183fbd837a021c1c117f47737e71c430b9d33915615f68c8dcb5e2f4e4dda4c9415d20a8b5fad9770b14067f2dd31a141a8a8da1f56eb2577715409dbf3c39b9bfa7b90c1acd838fe147c95f0e1ca9359a4cfd52367a73a6d6c548b492faa"
  
  private_key = datatypes.PrivateKey(bytes.fromhex(private_key_str))
  
  encryption = Encryption()
  encrypted_message = encryption.decrypt(bytes.fromhex(encrypted_message_str), private_key)

encrypt(data, public_key, shared_mac_data=b'')

Encrypt data with ECIES method to the given public key

1. generate r = random value

2. generate shared-secret = kdf( ecdhAgree(r, P) )

3. generate R = rG [same op as generating a public key]

4. 0x04 || R || AsymmetricEncrypt(shared-secret, plaintext) || tag

• Parameters:

  • data (bytes) – Data to be encrypted

  • public_key (PublicKey) – Public to be used to encrypt provided data.

  • shared_mac_data (bytes) – shared mac additional data as suffix.

• Return type: bytes

• Returns: Encrypted byte string

• Example:

  from human_protocol_sdk.legacy_encryption import Encryption
  from eth_keys import datatypes
  
  public_key_str = "0a1d228684bc8c8c7611df3264f04ebd823651acc46b28b3574d2e69900d5e34f04a26cf13237fa42ab23245b58060c239b356b0a276f57e8de1234c7100fcf9"
  
  public_key = datatypes.PublicKey(bytes.fromhex(private_key_str))
  
  encryption = Encryption()
  encrypted_message = encryption.encrypt(b'your message', public_key)

generate_private_key()

Generates a new SECP256K1 private key and return it

• Return type: PrivateKey

• Returns: New SECP256K1 private key.

• Example:

  from human_protocol_sdk.legacy_encryption import Encryption
  
  encryption = Encryption()
  private_key = encryption.generate_private_key()

static generate_public_key(private_key)

Generates a public key with combination to private key provided.

• Parameters: private_key (bytes) – Private to be used to create public key.

• Return type: PublicKey

• Returns: Public key object.

• Example:

  from human_protocol_sdk.legacy_encryption import Encryption
  
  private_key_str = "9822f95dd945e373300f8c8459a831846eda97f314689e01f7cf5b8f1c2298b3"
  
  public_key = Encryption.generate_public_key(bytes.fromhex(private_key_str))

static is_encrypted(data)

Checks whether data is already encrypted by verifying ecies header.

• Parameters: data (bytes) – Data to be checked.

• Return type: bool

• Returns: True if data is encrypted, False otherwise.

• Example:

  from human_protocol_sdk.legacy_encryption import Encryption
  
  encrypted_message_str = "0402f48d28d29ae3d681e4cbbe499be0803c2a9d94534d0a4501ab79fd531183fbd837a021c1c117f47737e71c430b9d33915615f68c8dcb5e2f4e4dda4c9415d20a8b5fad9770b14067f2dd31a141a8a8da1f56eb2577715409dbf3c39b9bfa7b90c1acd838fe147c95f0e1ca9359a4cfd52367a73a6d6c548b492faa"
  
  is_encrypted = Encryption.is_encrypted(bytes.fromhex(encrypted_message_str))

exception human_protocol_sdk.legacy_encryption.InvalidPublicKey

Bases: Exception

A custom exception raised when trying to convert bytes into an elliptic curve public key.