debian-mirror-gitlab/lib/gitlab/ci/ansi2json/signed_state.rb
2023-06-20 00:43:36 +05:30

74 lines
2 KiB
Ruby

# frozen_string_literal: true
require 'openssl'
module Gitlab
module Ci
module Ansi2json
class SignedState < ::Gitlab::Ci::Ansi2json::State
include Gitlab::Utils::StrongMemoize
SIGNATURE_KEY_SALT = 'gitlab-ci-ansi2json-state'
SEPARATOR = '--'
def encode
encoded = super
encoded + SEPARATOR + sign(encoded)
end
private
def sign(message)
::OpenSSL::HMAC.hexdigest(
signature_digest,
signature_key,
message
)
end
def verify(signed_message)
signature_length = signature_digest.digest_length * 2 # a byte is exactly two hexadecimals
message_length = signed_message.length - SEPARATOR.length - signature_length
return if message_length <= 0
signature = signed_message.last(signature_length)
message = signed_message.first(message_length)
return unless valid_signature?(message, signature)
message
end
def valid_signature?(message, signature)
expected_signature = sign(message)
expected_signature.bytesize == signature.bytesize &&
::OpenSSL.fixed_length_secure_compare(signature, expected_signature)
end
def decode_state(data)
return if data.blank?
encoded_state = verify(data)
if encoded_state.blank?
::Gitlab::AppLogger.warn(message: "#{self.class}: signature missing or invalid", invalid_state: data)
return
end
decoded_state = Base64.urlsafe_decode64(encoded_state)
return unless decoded_state.present?
::Gitlab::Json.parse(decoded_state)
end
def signature_digest
::OpenSSL::Digest.new('SHA256')
end
def signature_key
::Gitlab::Application.key_generator.generate_key(SIGNATURE_KEY_SALT, signature_digest.block_length)
end
strong_memoize_attr :signature_key
end
end
end
end