ntru: Fix compiler warning caused by ++/-- on righthand side of an assignment

The behavior of stuff like x = --x; (or x++) is not defined.

diff --git a/src/libstrongswan/plugins/ntru/ntru_crypto/ntru_crypto_ntru_encrypt.c b/src/libstrongswan/plugins/ntru/ntru_crypto/ntru_crypto_ntru_encrypt.c
index ea230a07473b3c8036591bb6f2fa72cd353f2b3f..40d80d316a01fe23824b59b073f88cbececcbe52 100644 (file)
--- a/src/libstrongswan/plugins/ntru/ntru_crypto/ntru_crypto_ntru_encrypt.c
+++ b/src/libstrongswan/plugins/ntru/ntru_crypto/ntru_crypto_ntru_encrypt.c
@@ -591,9 +591,9 @@ ntru_crypto_ntru_decrypt(
 
     for (i = 0; i < cmprime_len; i++) {
         if (Mtrin_buf[i] == 1)
-            ringel_buf2[i] = --ringel_buf2[i] & mod_q_mask;
+            ringel_buf2[i] = (ringel_buf2[i] - 1) & mod_q_mask;
         else if (Mtrin_buf[i] == 2)
-            ringel_buf2[i] = ++ringel_buf2[i] & mod_q_mask;
+            ringel_buf2[i] = (ringel_buf2[i] + 1) & mod_q_mask;
     }
     if (params->is_product_form)
         ringel_buf2[i] = (ringel_buf2[i] + m1) & mod_q_mask;
@@ -940,11 +940,11 @@ ntru_crypto_ntru_encrypt_keygen(
 
             for (i = 0; i < dF3; i++) {
                 uint16_t index = F_buf[dF3_offset + i];
-                ringel_buf1[index] = ++ringel_buf1[index] & mod_q_mask;
+                ringel_buf1[index] = (ringel_buf1[index] + 1) & mod_q_mask;
             }
             for (; i < (dF3 << 1); i++) {
                 uint16_t index = F_buf[dF3_offset + i];
-                ringel_buf1[index] = --ringel_buf1[index] & mod_q_mask;
+                ringel_buf1[index] = (ringel_buf1[index] - 1) & mod_q_mask;
             }
 
         } else {