Class AesGcm

Converts a raw private key in bytes to its corresponding JSON Web Key (JWK) format.

Remarks

This method accepts a symmetric key represented as a byte array (Uint8Array) and converts it into a JWK object for use with AES-GCM (Advanced Encryption Standard - Galois/Counter Mode). The conversion process involves encoding the key into base64url format and setting the appropriate JWK parameters.

The resulting JWK object includes the following properties:

• kty: Key Type, set to 'oct' for Octet Sequence (representing a symmetric key).
• k: The symmetric key, base64url-encoded.
• kid: Key ID, generated based on the JWK thumbprint.

Example

const privateKeyBytes = new Uint8Array([...]); // Replace with actual symmetric key bytes
const privateKey = await AesGcm.bytesToPrivateKey({ privateKeyBytes });
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Decrypts the provided data using AES-GCM.

Remarks

This method performs AES-GCM decryption on the given encrypted data using the specified key. It requires an initialization vector (IV), the encrypted data along with the decryption key, and optionally, additional authenticated data (AAD). The method returns the decrypted data as a Uint8Array. The optional tagLength parameter specifies the size in bits of the authentication tag used when encrypting the data. If not specified, the default tag length of 128 bits is used.

Example

const encryptedData = new Uint8Array([...]); // Encrypted data
const iv = new Uint8Array([...]); // Initialization vector used during encryption
const additionalData = new Uint8Array([...]); // Optional additional authenticated data
const key = { ... }; // A Jwk object representing the AES key
const decryptedData = await AesGcm.decrypt({
  data: encryptedData,
  iv,
  additionalData,
  key,
  tagLength: 128 // Optional tag length in bits
});
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Encrypts the provided data using AES-GCM.

Remarks

This method performs AES-GCM encryption on the given data using the specified key. It requires an initialization vector (IV), the encrypted data along with the decryption key, and optionally, additional authenticated data (AAD). The method returns the encrypted data as a Uint8Array. The optional tagLength parameter specifies the size in bits of the authentication tag generated in the encryption operation and used for authentication in the corresponding decryption. If not specified, the default tag length of 128 bits is used.

Example

const data = new TextEncoder().encode('Messsage');
const iv = new Uint8Array([...]); // Initialization vector
const additionalData = new Uint8Array([...]); // Optional additional authenticated data
const key = { ... }; // A Jwk object representing an AES key
const encryptedData = await AesGcm.encrypt({
  data,
  iv,
  additionalData,
  key,
  tagLength: 128 // Optional tag length in bits
});
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Generates a symmetric key for AES in Galois/Counter Mode (GCM) in JSON Web Key (JWK) format.

Remarks

This method creates a new symmetric key of a specified length suitable for use with AES-GCM encryption. It leverages cryptographically secure random number generation to ensure the uniqueness and security of the key. The generated key adheres to the JWK format, facilitating compatibility with common cryptographic standards and ease of use in various cryptographic applications.

The generated key includes these components:

• kty: Key Type, set to 'oct' for Octet Sequence, indicating a symmetric key.
• k: The symmetric key component, base64url-encoded.
• kid: Key ID, generated based on the JWK thumbprint, providing a unique identifier.

Example

const length = 256; // Length of the key in bits (e.g., 128, 192, 256)
const privateKey = await AesGcm.generateKey({ length });
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Converts a private key from JSON Web Key (JWK) format to a raw byte array (Uint8Array).

Remarks

This method takes a symmetric key in JWK format and extracts its raw byte representation. It focuses on the 'k' parameter of the JWK, which represents the symmetric key component in base64url encoding. The method decodes this value into a byte array, providing the symmetric key in its raw binary form.

Example

const privateKey = { ... }; // A symmetric key in JWK format
const privateKeyBytes = await AesGcm.privateKeyToBytes({ privateKey });
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