CfnKey

Creates an AWS Payment Cryptography key, a logical representation of a cryptographic key, that is unique in your account and AWS Region . You use keys for cryptographic functions such as encryption and decryption. In addition to the key material used in cryptographic operations, an AWS Payment Cryptography key includes metadata such as the key ARN, key usage, key origin, creation date, description, and key state. When you create a key, you specify both immutable and mutable data about the key. The immutable data contains key attributes that define the scope and cryptographic operations that you can perform using the key, for example key class (example: `SYMMETRIC_KEY` ), key algorithm (example: `TDES_2KEY` ), key usage (example: `TR31_P0_PIN_ENCRYPTION_KEY` ) and key modes of use (example: `Encrypt` ). AWS Payment Cryptography binds key attributes to keys using key blocks when you store or export them. AWS Payment Cryptography stores the key contents wrapped and never stores or transmits them in the clear. For information about valid combinations of key attributes, see [Understanding key attributes](https://docs.aws.amazon.com/payment-cryptography/latest/userguide/keys-validattributes.html) in the *AWS Payment Cryptography User Guide* . The mutable data contained within a key includes usage timestamp and key deletion timestamp and can be modified after creation. You can use the `CreateKey` operation to generate an ECC (Elliptic Curve Cryptography) key pair used for establishing an ECDH (Elliptic Curve Diffie-Hellman) key agreement between two parties. In the ECDH key agreement process, both parties generate their own ECC key pair with key usage K3 and exchange the public keys. Each party then use their private key, the received public key from the other party, and the key derivation parameters including key derivation function, hash algorithm, derivation data, and key algorithm to derive a shared key. To maintain the single-use principle of cryptographic keys in payments, ECDH derived keys should not be used for multiple purposes, such as a `TR31_P0_PIN_ENCRYPTION_KEY` and `TR31_K1_KEY_BLOCK_PROTECTION_KEY` . When creating ECC key pairs in AWS Payment Cryptography you can optionally set the `DeriveKeyUsage` parameter, which defines the key usage bound to the symmetric key that will be derived using the ECC key pair. *Cross-account use* : This operation can't be used across different AWS accounts. *Related operations:* - [DeleteKey](https://docs.aws.amazon.com/payment-cryptography/latest/APIReference/API_DeleteKey.html) - [GetKey](https://docs.aws.amazon.com/payment-cryptography/latest/APIReference/API_GetKey.html) - [ListKeys](https://docs.aws.amazon.com/payment-cryptography/latest/APIReference/API_ListKeys.html)