Implement peer review feedback

Author: kaleb-himes

wolfcrypt/src/aes.c

@@ -10643,11 +10643,6 @@ static WARN_UNUSED_RESULT int roll_auth(
     word32 remainder;
     int ret;
 
-    /* Sanity check on authIn to prevent segfault in xorbuf() where
-     * variable 'in' is dereferenced as the mask 'm' in misc.c */
-    if (in == NULL)
-        return BAD_FUNC_ARG;
-
     /* encode the length in */
     if (inSz <= 0xFEFF) {
         authLenSz = 2;
@@ -10766,6 +10761,11 @@ int wc_AesCcmEncrypt(Aes* aes, byte* out, const byte* in, word32 inSz,
             authTagSz > AES_BLOCK_SIZE)
         return BAD_FUNC_ARG;
 
+    /* Sanity check on authIn to prevent segfault in xorbuf() where
+     * variable 'in' is dereferenced as the mask 'm' in misc.c */
+    if (authIn == NULL && authInSz > 0)
+        return BAD_FUNC_ARG;
+
     /* sanity check on tag size */
     if (wc_AesCcmCheckTagSize((int)authTagSz) != 0) {
         return BAD_FUNC_ARG;
@@ -10908,6 +10908,12 @@ int  wc_AesCcmDecrypt(Aes* aes, byte* out, const byte* in, word32 inSz,
         authTagSz > AES_BLOCK_SIZE)
         return BAD_FUNC_ARG;
 
+    /* Sanity check on authIn to prevent segfault in xorbuf() where
+     * variable 'in' is dereferenced as the mask 'm' in misc.c */
+    if (authIn == NULL && authInSz > 0)
+        return BAD_FUNC_ARG;
+
+
     /* sanity check on tag size */
     if (wc_AesCcmCheckTagSize((int)authTagSz) != 0) {
         return BAD_FUNC_ARG;