1 files changed, 98 insertions, 0 deletions
diff --git a/vendor/acme-client/lib/acme/client/crypto.rb b/vendor/acme-client/lib/acme/client/crypto.rb
new file mode 100644
index 0000000..dfa5cdc
--- /dev/null
+++ b/vendor/acme-client/lib/acme/client/crypto.rb
@@ -0,0 +1,98 @@
+class Acme::Client::Crypto
+  attr_reader :private_key
+
+  def initialize(private_key)
+    @private_key = private_key
+  end
+
+  def generate_signed_jws(header:, payload:)
+    header = { typ: 'JWT', alg: jws_alg, jwk: jwk }.merge(header)
+
+    encoded_header = urlsafe_base64(header.to_json)
+    encoded_payload = urlsafe_base64(payload.to_json)
+    signature_data = "#{encoded_header}.#{encoded_payload}"
+
+    signature = private_key.sign digest, signature_data
+    encoded_signature = urlsafe_base64(signature)
+
+    {
+      protected: encoded_header,
+      payload: encoded_payload,
+      signature: encoded_signature
+    }.to_json
+  end
+
+  def thumbprint
+    urlsafe_base64 digest.digest(jwk.to_json)
+  end
+
+  def digest
+    OpenSSL::Digest::SHA256.new
+  end
+
+  def urlsafe_base64(data)
+    Base64.urlsafe_encode64(data).sub(/[\s=]*\z/, '')
+  end
+
+  private
+
+  def jws_alg
+    { 'RSA' => 'RS256', 'EC' => 'ES256' }.fetch(jwk[:kty])
+  end
+
+  def jwk
+    @jwk ||= case private_key
+             when OpenSSL::PKey::RSA
+               rsa_jwk
+             when OpenSSL::PKey::EC
+               ec_jwk
+             else
+               raise ArgumentError, "Can't handle #{private_key} as private key, only OpenSSL::PKey::RSA and OpenSSL::PKey::EC"
+    end
+  end
+
+  def rsa_jwk
+    {
+      e: urlsafe_base64(public_key.e.to_s(2)),
+      kty: 'RSA',
+      n: urlsafe_base64(public_key.n.to_s(2))
+    }
+  end
+
+  def ec_jwk
+    {
+      crv: curve_name,
+      kty: 'EC',
+      x: urlsafe_base64(coordinates[:x].to_s(2)),
+      y: urlsafe_base64(coordinates[:y].to_s(2))
+    }
+  end
+
+  def curve_name
+    {
+      'prime256v1' => 'P-256',
+      'secp384r1' => 'P-384',
+      'secp521r1' => 'P-521'
+    }.fetch(private_key.group.curve_name) { raise ArgumentError, 'Unknown EC curve' }
+  end
+
+  # rubocop:disable Metrics/AbcSize
+  def coordinates
+    @coordinates ||= begin
+      hex = public_key.to_bn.to_s(16)
+      data_len = hex.length - 2
+      hex_x = hex[2, data_len / 2]
+      hex_y = hex[2 + data_len / 2, data_len / 2]
+
+      {
+        x: OpenSSL::BN.new([hex_x].pack('H*'), 2),
+        y: OpenSSL::BN.new([hex_y].pack('H*'), 2)
+      }
+    end
+  end
+  # rubocop:enable Metrics/AbcSize
+
+  def public_key
+    @public_key ||= private_key.public_key
+  end
+end