Avoid undefined behavior with unaligned accesses

[openssl.git] / crypto / modes / ofb128.c

diff --git a/crypto/modes/ofb128.c b/crypto/modes/ofb128.c
index 2eca09bc1b03f928813729e44c7ede4a1d623bc9..e9b24f863eea16a6069bd5fc57968fd02bc189e7 100644 (file)
--- a/crypto/modes/ofb128.c
+++ b/crypto/modes/ofb128.c
@@ -11,6 +11,12 @@
 #include <openssl/crypto.h>
 #include "crypto/modes.h"
 
+#if defined(__GNUC__) && !defined(STRICT_ALIGNMENT)
+typedef size_t size_t_aX __attribute((__aligned__(1)));
+#else
+typedef size_t size_t_aX;
+#endif
+
 /*
  * The input and output encrypted as though 128bit ofb mode is being used.
  * The extra state information to record how much of the 128bit block we have
@@ -41,8 +47,9 @@ void CRYPTO_ofb128_encrypt(const unsigned char *in, unsigned char *out,
             while (len >= 16) {
                 (*block) (ivec, ivec, key);
                 for (; n < 16; n += sizeof(size_t))
-                    *(size_t *)(out + n) =
-                        *(size_t *)(in + n) ^ *(size_t *)(ivec + n);
+                    *(size_t_aX *)(out + n) =
+                        *(size_t_aX *)(in + n)
+                        ^ *(size_t_aX *)(ivec + n);
                 len -= 16;
                 out += 16;
                 in += 16;