Class: Cryptosphere::Blob::Builder

Inherits:
Object
  • Object
show all
Defined in:
lib/cryptosphere/blobs/blob.rb

Overview

Encrypt a node and insert it into the local store

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Builder

Returns a new instance of Builder.



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# File 'lib/cryptosphere/blobs/blob.rb', line 64

def initialize
  @hash_function = Cryptosphere.hash_function
  @hash_function << PREFIX

  @file = Tempfile.new 'cryptosphere'
end

Instance Method Details

#finish ⇒ Object 



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# File 'lib/cryptosphere/blobs/blob.rb', line 77

def finish
  keys = Cryptosphere.kdf(@hash_function.digest, size: 64)
  key, iv = keys[0...32], keys[32...64]

  block_cipher = Cryptosphere.block_cipher
  block_cipher.encrypt
  block_cipher.key, block_cipher.iv = key, iv

  @file.rewind
  output = Tempfile.new 'cryptosphere'

  begin
    hash_function = Cryptosphere.hash_function
    while plaintext = @file.read(4096)
      ciphertext = block_cipher.update(plaintext)
      output << ciphertext
      hash_function << ciphertext
    end

    ciphertext = block_cipher.final
    output << ciphertext
    hash_function << ciphertext
    output.close

    node_id = hash_function.hexdigest
    FileUtils.mv output.path, File.join(Blob.path, node_id)

    Blob.new(node_id, key + iv)
  rescue Exception
    output.close rescue nil
    output.unlink rescue nil

    raise
  end
ensure
  @file.close rescue nil
  @file.unlink rescue nil
end

#write(data) ⇒ Object Also known as: << 



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# File 'lib/cryptosphere/blobs/blob.rb', line 71

def write(data)
  @hash_function << data
  @file << data
end