It was pointed out to me that if the requested size is 0, we shouldn't

ty to allocate anything at all.  This will allow eNULL to still work.

PR: 751
Notified by: Lutz Jaenicke

crypto/evp/evp_enc.c

@@ -148,11 +148,18 @@ int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *imp
 #endif
 
 		ctx->cipher=cipher;
-		ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);
-		if (!ctx->cipher_data)
+		if (ctx->cipher->ctx_size)
 			{
-			EVPerr(EVP_F_EVP_CIPHERINIT, ERR_R_MALLOC_FAILURE);
-			return 0;
+			ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);
+			if (!ctx->cipher_data)
+				{
+				EVPerr(EVP_F_EVP_CIPHERINIT, ERR_R_MALLOC_FAILURE);
+				return 0;
+				}
+			}
+		else
+			{
+			ctx->cipher_data = NULL;
 			}
 		ctx->key_len = cipher->key_len;
 		ctx->flags = 0;