Fix for SP math only case to ensure fast math and heap math are disabled. Also fix build error for case where WOLFSSL_HAVE_SP_ECC is defined, but HAVE_ECC is not. ZD 16419

Author: dgarske

wolfssl/wolfcrypt/settings.h

@@ -2033,17 +2033,22 @@ extern void uITRON4_free(void *p) ;
          *      Constant time: Always
          *      Enable:        WOLFSSL_SP_MATH_ALL
          */
+        #undef USE_FAST_MATH
+        #undef USE_INTEGER_HEAP_MATH
     #elif defined(WOLFSSL_SP_MATH)
         /*  2) SP Math with restricted key sizes: wolfSSL proprietary math
          *         implementation (sp_*.c).
          *      Constant time: Always
          *      Enable:        WOLFSSL_SP_MATH
          */
+        #undef USE_FAST_MATH
+        #undef USE_INTEGER_HEAP_MATH
     #elif defined(USE_FAST_MATH)
         /*  3) Tom's Fast Math: Stack based (tfm.c)
          *      Constant time: Only with TFM_TIMING_RESISTANT
          *      Enable:        USE_FAST_MATH
          */
+        #undef USE_INTEGER_HEAP_MATH
     #elif defined(USE_INTEGER_HEAP_MATH)
         /*  4) Integer Heap Math:  Heap based (integer.c)
          *      Constant time: Not supported

wolfssl/wolfcrypt/sp.h

@@ -41,7 +41,11 @@
 #include <wolfssl/wolfcrypt/wolfmath.h>
 #include <wolfssl/wolfcrypt/sp_int.h>
 
-#include <wolfssl/wolfcrypt/ecc.h>
+#if defined(HAVE_ECC) && defined(WOLFSSL_HAVE_SP_ECC)
+    #include <wolfssl/wolfcrypt/ecc.h>
+#else
+    #undef WOLFSSL_HAVE_SP_ECC
+#endif
 
 #ifdef noinline
     #define SP_NOINLINE noinline