From 964eaad78ccdc6c4537664924e6082b08cc1c8ee Mon Sep 17 00:00:00 2001
From: "Dr. Stephen Henson" <steve@openssl.org>
Date: Tue, 16 Oct 2012 22:46:08 +0000
Subject: [PATCH] Don't require tag before ciphertext in AESGCM mode

---
 crypto/evp/e_aes.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/crypto/evp/e_aes.c b/crypto/evp/e_aes.c
index 46ffd99e2a..783ef2f7d5 100644
--- a/crypto/evp/e_aes.c
+++ b/crypto/evp/e_aes.c
@@ -1343,8 +1343,6 @@ static int aes_gcm_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
 
 	if (!gctx->iv_set)
 		return -1;
-	if (!ctx->encrypt && gctx->taglen < 0)
-		return -1;
 	if (in)
 		{
 		if (out == NULL)
@@ -1386,6 +1384,8 @@ static int aes_gcm_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
 		{
 		if (!ctx->encrypt)
 			{
+			if (gctx->taglen < 0)
+				return -1;
 			if (CRYPTO_gcm128_finish(&gctx->gcm,
 					ctx->buf, gctx->taglen) != 0)
 				return -1;