Class: BlindIndex::KeyGenerator

Inherits:
Object
  • Object
show all
Defined in:
lib/blind_index/key_generator.rb

Instance Method Summary collapse

Constructor Details

#initialize(master_key) ⇒ KeyGenerator

Returns a new instance of KeyGenerator.



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# File 'lib/blind_index/key_generator.rb', line 3

def initialize(master_key)
  @master_key = master_key
end

Instance Method Details

#index_key(table:, bidx_attribute:) ⇒ Object

pattern ported from CipherSweet ciphersweet.paragonie.com/internals/key-hierarchy

Raises:

  • (ArgumentError) 


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# File 'lib/blind_index/key_generator.rb', line 9

def index_key(table:, bidx_attribute:)
  raise ArgumentError, "Missing table for key generation" if table.to_s.empty?
  raise ArgumentError, "Missing field for key generation" if bidx_attribute.to_s.empty?

  c = "\x7E"*32
  root_key = hkdf(BlindIndex.decode_key(@master_key, name: "Master key"), salt: table.to_s, info: "#{c}#{bidx_attribute}", length: 32, hash: "sha384")
  hash_hmac("sha256", pack([table, bidx_attribute, bidx_attribute]), root_key)
end