From e4f8f8907c8d04c54acf7791947295f8d9abf959 Mon Sep 17 00:00:00 2001
From: akr <akr@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Thu, 14 Nov 2013 10:58:15 +0000
Subject: [PATCH] * test/openssl/test_cipher.rb (test_aes_gcm_wrong_tag): Don't
 use   String#succ because it can make modified (wrong) auth_tag longer   than
 16 bytes.  The longer auth_tag makes that   EVP_CIPHER_CTX_ctrl (and
 internally aes_gcm_ctrl) fail.   [ruby-core:55143] [Bug #8439] reported by
 Vit Ondruch.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43676 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog                   | 8 ++++++++
 test/openssl/test_cipher.rb | 3 ++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index 04f7867..c6beb5a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -24,6 +24,14 @@
 	  time to invocation of signal handler from 0.01 sec to 0.2 sec.
 	  RubyCI report error on mswin. reported by @unak
 
+Thu Nov 14 19:53:00 2013  Tanaka Akira  <akr@fsij.org>
+
+	* test/openssl/test_cipher.rb (test_aes_gcm_wrong_tag): Don't use
+	  String#succ because it can make modified (wrong) auth_tag longer
+	  than 16 bytes.  The longer auth_tag makes that
+	  EVP_CIPHER_CTX_ctrl (and internally aes_gcm_ctrl) fail.
+	  [ruby-core:55143] [Bug #8439] reported by Vit Ondruch.
+
 Wed Nov 13 11:57:01 2013  CHIKANAGA Tomoyuki  <nagachika@ruby-lang.org>
 
 	* lib/rubygems: Update to RubyGems 2.0.14. [ruby-core:58300]
diff --git a/test/openssl/test_cipher.rb b/test/openssl/test_cipher.rb
index 088dbc1..156fa2a 100644
--- a/test/openssl/test_cipher.rb
+++ b/test/openssl/test_cipher.rb
@@ -187,7 +187,8 @@ def test_aes_gcm_wrong_tag
       tag = cipher.auth_tag
 
       decipher = new_decryptor('aes-128-gcm', key, iv)
-      decipher.auth_tag = tag[0..-2] << tag[-1].succ
+      tag.setbyte(-1, (tag.getbyte(-1) + 1) & 0xff)
+      decipher.auth_tag = tag
       decipher.auth_data = "aad"
 
       assert_raise OpenSSL::Cipher::CipherError do
-- 
1.8.5.1