Class: WSDL::Security::Digester

Inherits:
Object
  • Object
show all
Defined in:
lib/wsdl/security/digester.rb

Overview

Handles digest calculation for XML Digital Signatures.

The Digester computes cryptographic hashes of XML content for use in signature Reference elements. It supports SHA-1, SHA-256, and SHA-512 algorithms.

Examples:

Basic usage

digester = Digester.new
digest = digester.digest("content to hash")

With Base64 encoding (for XML output)

digester = Digester.new(algorithm: :sha256)
base64_digest = digester.base64_digest(canonicalized_xml)

See Also:

Constant Summary collapse

Digest =

Local alias for digest algorithm constants

Constants::Algorithms::Digest
ALGORITHMS =

Supported digest algorithms.

Each algorithm specifies:

  • :id - The URI used in XML DigestMethod elements
  • :name - The OpenSSL digest name
  • :klass - The OpenSSL::Digest class to use
{
  # SHA-1 (legacy, still widely used in WS-Security)
  sha1: {
    id: Digest::SHA1,
    name: 'SHA1',
    klass: OpenSSL::Digest::SHA1
  },

  # SHA-224
  sha224: {
    id: Digest::SHA224,
    name: 'SHA224',
    klass: OpenSSL::Digest::SHA224
  },

  # SHA-256 (recommended)
  sha256: {
    id: Digest::SHA256,
    name: 'SHA256',
    klass: OpenSSL::Digest::SHA256
  },

  # SHA-384
  sha384: {
    id: Digest::SHA384,
    name: 'SHA384',
    klass: OpenSSL::Digest::SHA384
  },

  # SHA-512 (strongest)
  sha512: {
    id: Digest::SHA512,
    name: 'SHA512',
    klass: OpenSSL::Digest::SHA512
  }
}.freeze
DEFAULT_ALGORITHM =

Default algorithm to use

:sha256

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(algorithm: DEFAULT_ALGORITHM) ⇒ Digester

Creates a new Digester instance.

Parameters:

  • algorithm (Symbol) (defaults to: DEFAULT_ALGORITHM) —

    the digest algorithm to use (default: :sha256)

Raises:

  • (ArgumentError) —

    if an unknown algorithm is specified



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# File 'lib/wsdl/security/digester.rb', line 90

def initialize(algorithm: DEFAULT_ALGORITHM)
  @algorithm_key = algorithm
  @algorithm = ALGORITHMS[algorithm] or
    raise ArgumentError, "Unknown digest algorithm: #{algorithm.inspect}. " \
                         "Valid options: #{ALGORITHMS.keys.join(', ')}"
end

Instance Attribute Details

#algorithm ⇒ Hash (readonly)

Returns the current algorithm configuration.

Returns:

  • (Hash) —

    the algorithm settings



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# File 'lib/wsdl/security/digester.rb', line 77

def algorithm
  @algorithm
end

#algorithm_key ⇒ Symbol (readonly)

Returns the algorithm symbol.

Returns:

  • (Symbol) —

    the algorithm key (e.g., :sha256)



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# File 'lib/wsdl/security/digester.rb', line 81

def algorithm_key
  @algorithm_key
end

Class Method Details

.base64_digest(data, algorithm: DEFAULT_ALGORITHM) ⇒ String

Class method to compute a Base64-encoded digest.

Parameters:

  • data (String) —

    the data to digest

  • algorithm (Symbol) (defaults to: DEFAULT_ALGORITHM) —

    the algorithm to use (default: :sha256)

Returns:

  • (String) —

    the Base64-encoded digest



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# File 'lib/wsdl/security/digester.rb', line 197

def self.base64_digest(data, algorithm: DEFAULT_ALGORITHM)
  new(algorithm: algorithm).base64_digest(data)
end

.digest(data, algorithm: DEFAULT_ALGORITHM, encode: nil) ⇒ String

Class method to compute a digest with default settings.

Parameters:

  • data (String) —

    the data to digest

  • algorithm (Symbol) (defaults to: DEFAULT_ALGORITHM) —

    the algorithm to use (default: :sha256)

  • encode (Symbol, nil) (defaults to: nil) —

    encoding format (:base64, :hex, or nil for raw)

Returns:

  • (String) —

    the digest in the specified format



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# File 'lib/wsdl/security/digester.rb', line 177

def self.digest(data, algorithm: DEFAULT_ALGORITHM, encode: nil)
  digester = new(algorithm: algorithm)

  case encode
  when :base64
    digester.base64_digest(data)
  when :hex
    digester.hex_digest(data)
  else
    digester.digest(data)
  end
end

Instance Method Details

#algorithm_id ⇒ String

Returns the algorithm URI for use in XML DigestMethod elements.

Returns:

  • (String) —

    the digest algorithm URI



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# File 'lib/wsdl/security/digester.rb', line 138

def algorithm_id
  @algorithm[:id]
end

#algorithm_name ⇒ String

Returns the OpenSSL digest name.

Returns:

  • (String) —

    the digest algorithm name (e.g., 'SHA256')



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# File 'lib/wsdl/security/digester.rb', line 146

def algorithm_name
  @algorithm[:name]
end

#base64_digest(data) ⇒ String

Computes the digest and returns it as a Base64-encoded string.

This is the format required for XML DigestValue elements.

Examples:

digester.base64_digest("hello world")
# => "Kq5sNclPz7QV2+lfQIuc6R7oRu0="

Parameters:

  • data (String) —

    the data to digest

Returns:

  • (String) —

    the Base64-encoded digest



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# File 'lib/wsdl/security/digester.rb', line 121

def base64_digest(data)
  Base64.strict_encode64(digest(data))
end

#digest(data) ⇒ String

Computes the digest of the given data.

Examples:

digester.digest("hello world")
# => binary string

Parameters:

  • data (String) —

    the data to digest

Returns:

  • (String) —

    the raw binary digest



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# File 'lib/wsdl/security/digester.rb', line 106

def digest(data)
  @algorithm[:klass].digest(data)
end

#digest_length ⇒ Integer

Returns the digest length in bytes.

Returns:

  • (Integer) —

    the digest length



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# File 'lib/wsdl/security/digester.rb', line 154

def digest_length
  @algorithm[:klass].new.digest_length
end

#hex_digest(data) ⇒ String

Computes the digest and returns it as a hexadecimal string.

Parameters:

  • data (String) —

    the data to digest

Returns:

  • (String) —

    the hexadecimal digest



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# File 'lib/wsdl/security/digester.rb', line 130

def hex_digest(data)
  @algorithm[:klass].hexdigest(data)
end

#new_digest ⇒ OpenSSL::Digest

Creates a new OpenSSL::Digest instance for this algorithm.

This is useful when you need to feed data incrementally or when signing.

Returns:

  • (OpenSSL::Digest) —

    a new digest instance



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# File 'lib/wsdl/security/digester.rb', line 165

def new_digest
  @algorithm[:klass].new
end