1 files changed, 4 insertions, 6 deletions
diff --git a/activesupport/lib/active_support/key_generator.rb b/activesupport/lib/active_support/key_generator.rb
index 7f73f9ddfc..7eafbb571f 100644
--- a/activesupport/lib/active_support/key_generator.rb
+++ b/activesupport/lib/active_support/key_generator.rb
@@ -15,9 +15,8 @@ module ActiveSupport
     end
 
     # Returns a derived key suitable for use.  The default key_size is chosen
-    # to be compatible with the default settings of ActiveSupport::MessageVerifier.
-    # i.e. OpenSSL::Digest::SHA1#block_length
-    def generate_key(salt, key_size=64)
+    # to be compatible with the acceptable key length of aes-256-cbc, the default cipher.
+    def generate_key(salt, key_size=32)
       OpenSSL::PKCS5.pbkdf2_hmac_sha1(@secret, salt, @iterations, key_size)
     end
   end
@@ -32,9 +31,8 @@ module ActiveSupport
     end
 
     # Returns a derived key suitable for use.  The default key_size is chosen
-    # to be compatible with the default settings of ActiveSupport::MessageVerifier.
-    # i.e. OpenSSL::Digest::SHA1#block_length
-    def generate_key(salt, key_size=64)
+    # to be compatible with the acceptable key length of aes-256-cbc, the default cipher.
+    def generate_key(salt, key_size=32)
       @cache_keys["#{salt}#{key_size}"] ||= @key_generator.generate_key(salt, key_size)
     end
   end