EncryptedBlock

Overview

The EncryptedBlock class represents an encrypted block. It extends the EphemeralBlock class and adds encryption-specific header data and overhead calculations. This class is used to handle encrypted data blocks in the Owner Free File System.

Methods

from

• Purpose: Creates an instance of EncryptedBlock.
• Parameters:
  • type (BlockType): The type of the block.
  • dataType (BlockDataType): The type of data in the block.
  • blockSize (BlockSize): The size of the block.
  • data (Buffer): The encrypted data.
  • checksum (ChecksumBuffer): The checksum of the data.

  • creator (Member

    GuidV4): The creator of the block.

  • dateCreated (Date): The date the block was created.
  • lengthBeforeEncryption (number): The actual data length before encryption.
  • canRead (boolean): Whether the block can be read.
  • canPersist (boolean): Whether the block can be persisted.
• Returns: A new EncryptedBlock instance.
• Example:

  const block = await EncryptedBlock.from(
    BlockType.Encrypted,
    BlockDataType.EncryptedData,
    BlockSize.Small,
    Buffer.from('encrypted data'),
    StaticHelpersChecksum.calculateChecksum(Buffer.from('encrypted data')),
    creator,
  );
  

constructor

• Purpose: Creates an instance of EncryptedBlock.
• Parameters:
  • type (BlockType): The type of the block.
  • dataType (BlockDataType): The type of data in the block.
  • blockSize (BlockSize): The size of the block.
  • data (Buffer): The encrypted data.
  • checksum (ChecksumBuffer): The checksum of the data.
  • dateCreated (Date): The date the block was created.
  • metadata (IEncryptedBlockMetadata): The block metadata.
  • canRead (boolean): Whether the block can be read.
  • canPersist (boolean): Whether the block can be persisted.
• Example:

  const block = new EncryptedBlock(
    BlockType.Encrypted,
    BlockDataType.EncryptedData,
    BlockSize.Small,
    Buffer.from('encrypted data'),
    StaticHelpersChecksum.calculateChecksum(Buffer.from('encrypted data')),
    new Date(),
    metadata,
  );
  

ephemeralPublicKey

• Purpose: The ephemeral public key used to encrypt the data.
• Type: Getter.
• Returns: The ephemeral public key.
• Example:

  console.log(block.ephemeralPublicKey);
  

iv

• Purpose: The initialization vector used to encrypt the data.
• Type: Getter.
• Returns: The initialization vector.
• Example:

  console.log(block.iv);
  

authTag

• Purpose: The authentication tag used to encrypt the data.
• Type: Getter.
• Returns: The authentication tag.
• Example:

  console.log(block.authTag);
  

totalOverhead

• Purpose: The total overhead of the block, including encryption overhead.
• Type: Getter.
• Returns: The total overhead.
• Example:

  console.log(block.totalOverhead);
  

layerHeaderData

• Purpose: Get this layer’s header data (encryption metadata).
• Type: Getter.
• Returns: This layer’s header data.
• Example:

  console.log(block.layerHeaderData);
  

payload

• Purpose: Get the encrypted payload data (excluding the encryption header).
• Type: Getter.
• Returns: The encrypted payload data.
• Example:

  console.log(block.payload);
  

payloadLength

• Purpose: Get the length of the payload.
• Type: Getter.
• Returns: The length of the payload.
• Example:

  console.log(block.payloadLength);
  

capacity

• Purpose: Get the usable capacity after accounting for overhead.
• Type: Getter.
• Returns: The usable capacity.
• Example:

  console.log(block.capacity);
  

validateAsync

• Purpose: Override validateAsync to handle encrypted data properly.
• Returns: A promise that resolves when the validation is complete.
• Example:

  await block.validateAsync();
  

Conclusion

The EncryptedBlock class provides essential utilities for handling encrypted data blocks in the Owner Free File System, ensuring data integrity and security through encryption-specific header data and overhead calculations.