Secret testing with multiplier working.

kern/test/lib.c

@@ -1,6 +1,58 @@
+#include <kern/secret.h>
 #include <types.h>
 #include <thread.h>
 #include <test.h>
+#include <lib.h>
+
+/*
+ * Main success function for kernel tests. Prints a multiple of the secret if
+ * the secret is non-zero and the test succeeded. Otherwise prints a random
+ * number.
+ *
+ * Ideally we would multiply the secret (a large prime) by another large prime
+ * to ensure that factoring was hard, but that would require either primality
+ * testing (slow) or augmenting sys161 with a prime number generator. This is
+ * sufficient for now to prevent replay attacks.
+ */
+
+#define MIN_MULTIPLIER 0x80000000
+
+#ifndef SECRET_TESTING
+void
+success(bool status, uint32_t secret, const char * name) {
+	(void)secret;
+	if (status == SUCCESS) {
+		kprintf("%s: SUCCESS\n", name);
+	} else {	
+		kprintf("%s: FAIL\n", name);
+	}
+	return;
+}
+#else
+void
+success(bool status, uint32_t secret, const char * name) {
+	uint32_t multiplier;
+	// Make sure we can get large random numbers
+	KASSERT(randmax() == 0xffffffff);
+	while (1) {
+		multiplier = random();
+		// We can at least remove the obvious non-primes...
+		if (multiplier % 2 == 0) {
+			continue;
+		}
+		if (multiplier > MIN_MULTIPLIER) {
+			break;
+		}
+	}
+	uint64_t big_secret = (uint64_t) secret * (uint64_t) multiplier;
+	if (status == SUCCESS) {
+		kprintf("%s: SUCCESS (%llu)\n", name, big_secret);
+	} else {	
+		kprintf("%s: FAIL (%llu)\n", name, big_secret);
+	}
+	return;
+}
+#endif
 
 /*
  * Helper functions used by testing and problem driver code