54 lines
1.7 KiB
Ruby
54 lines
1.7 KiB
Ruby
# frozen_string_literal: true
|
|
|
|
module Gitlab
|
|
module JwtAuthenticatable
|
|
# Supposedly the effective key size for HMAC-SHA256 is 256 bits, i.e. 32
|
|
# bytes https://tools.ietf.org/html/rfc4868#section-2.6
|
|
SECRET_LENGTH = 32
|
|
|
|
def self.included(base)
|
|
base.extend(ClassMethods)
|
|
end
|
|
|
|
module ClassMethods
|
|
include Gitlab::Utils::StrongMemoize
|
|
|
|
def decode_jwt(encoded_message, jwt_secret = secret, issuer: nil, iat_after: nil)
|
|
options = { algorithm: 'HS256' }
|
|
options = options.merge(iss: issuer, verify_iss: true) if issuer.present?
|
|
options = options.merge(verify_iat: true) if iat_after.present?
|
|
|
|
decoded_message = JWT.decode(encoded_message, jwt_secret, true, options)
|
|
payload = decoded_message[0]
|
|
if iat_after.present?
|
|
raise JWT::DecodeError, "JWT iat claim is missing" if payload['iat'].blank?
|
|
|
|
iat = payload['iat'].to_i
|
|
raise JWT::ExpiredSignature, 'Token has expired' if iat < iat_after.to_i
|
|
end
|
|
|
|
decoded_message
|
|
end
|
|
|
|
def secret
|
|
strong_memoize(:secret) do
|
|
read_secret(secret_path)
|
|
end
|
|
end
|
|
|
|
def read_secret(path)
|
|
Base64.strict_decode64(File.read(path).chomp).tap do |bytes|
|
|
raise "#{path} does not contain #{SECRET_LENGTH} bytes" if bytes.length != SECRET_LENGTH
|
|
end
|
|
end
|
|
|
|
def write_secret(path = secret_path)
|
|
bytes = SecureRandom.random_bytes(SECRET_LENGTH)
|
|
File.open(path, 'w:BINARY', 0600) do |f|
|
|
f.chmod(0600) # If the file already existed, the '0600' passed to 'open' above was a no-op.
|
|
f.write(Base64.strict_encode64(bytes))
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|