From d73e21e6119a197b48d1ef7fd9a825276a97a592 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pavel=20Tvrd=C3=ADk?= <pawel.tvrdik@gmail.cz>
Date: Mon, 30 Mar 2015 18:54:09 +0200
Subject: [PATCH] Birdtest: IP One-Complement Checksum Tests

---
 lib/checksum_test.c | 105 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 105 insertions(+)
 create mode 100644 lib/checksum_test.c

diff --git a/lib/checksum_test.c b/lib/checksum_test.c
new file mode 100644
index 00000000..ede2ce06
--- /dev/null
+++ b/lib/checksum_test.c
@@ -0,0 +1,105 @@
+/*
+ *	BIRD Library -- IP One-Complement Checksum Tests
+ *
+ *	(c) 2015 CZ.NIC z.s.p.o.
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#include <stdio.h>
+
+#include "test/birdtest.h"
+#include "sysdep/config.h"
+#include "lib/null.h"
+
+void bug(const char *msg, ...);
+#include "lib/checksum.h"
+#include "lib/checksum.c" /* REMOVE ME */
+
+#define MAX_NUM 10000
+
+static u16
+ipsum_calculate_expected(u32 *a)
+{
+  int i;
+  u32 sum = 0;
+
+  for(i = 0; i < MAX_NUM; i++)
+  {
+    sum += a[i] & 0xffff;
+    bt_debug("low) \t0x%08X \n", sum);
+
+    sum += a[i] >> 16;
+    bt_debug("high) \t0x%08X \n", sum);
+
+    u16 carry = sum >> 16;
+    sum = (sum & 0xffff) + carry;
+    bt_debug("carry) \t0x%08X \n\n", sum);
+  }
+  bt_debug("sum) \t0x%08X \n", sum);
+
+  sum = sum ^ 0xffff;
+  bt_debug("~sum) \t0x%08X \n", sum);
+
+  return sum;
+}
+
+static int
+t_calculate(void)
+{
+  u32 a[MAX_NUM];
+  int i;
+
+  for (i = 0; i < MAX_NUM; i++)
+    a[i] = bt_rand_num();
+
+  u16 sum_calculated   = ipsum_calculate(a, sizeof(a), NULL);
+  u16 sum_calculated_2 = ipsum_calculate(&a[0], sizeof(u32)*(MAX_NUM/2), &a[MAX_NUM/2], sizeof(u32)*(MAX_NUM - MAX_NUM/2), NULL);
+  bt_assert(sum_calculated == sum_calculated_2);
+
+  u16 sum_expected = ipsum_calculate_expected(a);
+
+  bt_debug("sum_calculated: %08X \n", sum_calculated);
+  bt_debug("sum_expected:   %08X \n", sum_expected);
+
+  bt_assert(sum_calculated == sum_expected);
+
+  return BT_SUCCESS;
+}
+
+static int
+t_verify(void)
+{
+  u32 a[MAX_NUM+1];
+  int i;
+
+  for (i = 0; i < MAX_NUM; i++)
+    a[i] = bt_rand_num();
+
+  u16 sum = ipsum_calculate_expected(a);
+
+  a[MAX_NUM] = sum;
+
+  bt_assert(ipsum_verify(a, sizeof(a) + sizeof(u32), NULL));
+
+  return BT_SUCCESS;
+}
+
+
+int
+main(int argc, char *argv[])
+{
+  bt_init(argc, argv);
+
+  bt_test_case(t_calculate, "Checksum of pseudo-random data");
+  bt_test_case(t_verify, "Verification of pseudo-random data.");
+
+  return 0;
+}
+
+/* Mockup */
+void
+bug(const char *msg, ...)
+{
+  abort();
+}