fletcher16_test.c 4.41 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57
/*
 *	BIRD Library -- Fletcher-16 Tests
 *
 *	(c) 2015 CZ.NIC z.s.p.o.
 *
 *	Can be freely distributed and used under the terms of the GNU GPL.
 */

#include "test/birdtest.h"
#include "lib/fletcher16.h"

static u16
straightforward_fletcher16_compute(const char *data)
{
  int count = strlen(data);

  u16 sum1 = 0;
  u16 sum2 = 0;
  int index;

  for (index = 0; index < count; ++index)
  {
    sum1 = (sum1 + data[index]) % 255;
    sum2 = (sum2 + sum1) % 255;
  }

  return (sum2 << 8) | sum1;
}

static u16
straightforward_fletcher16_checksum(const char *data)
{
  u16 csum;
  u8 c0,c1,f0,f1;

  csum = straightforward_fletcher16_compute(data);
  f0 = csum & 0xff;
  f1 = (csum >> 8) & 0xff;
  c0 = 0xff - ((f0 + f1) % 0xff);
  c1 = 0xff - ((f0 + c0) % 0xff);

  return (c1 << 8) | c0;
}

static int
test_fletcher16(void *out_, const void *in_, const void *expected_out_)
{
  u16 *out = out_;
  const char *in = in_;
  const u16 *expected_out = expected_out_;

  struct fletcher16_context ctxt;

  fletcher16_init(&ctxt);
  fletcher16_update(&ctxt, in, strlen(in));
  put_u16(out, fletcher16_compute(&ctxt));

58
  return *out == *expected_out;
59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74
}

static int
test_fletcher16_checksum(void *out_, const void *in_, const void *expected_out_)
{
  u16 *out = out_;
  const char *in = in_;
  const u16 *expected_out = expected_out_;

  struct fletcher16_context ctxt;
  int len = strlen(in);

  fletcher16_init(&ctxt);
  fletcher16_update(&ctxt, in, len);
  put_u16(out, fletcher16_final(&ctxt, len, len));

75
  return *out == *expected_out;
76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169
}

static int
t_fletcher16_compute(void)
{
  struct bt_pair test_vectors[] = {
    {
      .in  = "\001\002",
      .out = & (const u16) { 0x0403 },
    },
    {
      .in  = "",
      .out = & ((const u16) { straightforward_fletcher16_compute("") }),
    },
    {
      .in  = "a",
      .out = & ((const u16) { straightforward_fletcher16_compute("a") }),
    },
    {
      .in  = "abcd",
      .out = & ((const u16) { straightforward_fletcher16_compute("abcd") }),
    },
    {
      .in  = "message digest",
      .out = & ((const u16) { straightforward_fletcher16_compute("message digest") }),
    },
    {
      .in  = "abcdefghijklmnopqrstuvwxyz",
      .out = & ((const u16) { straightforward_fletcher16_compute("abcdefghijklmnopqrstuvwxyz") }),
    },
    {
      .in  = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
      .out = & ((const u16) { straightforward_fletcher16_compute("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789") }),
    },
    {
      .in  = "12345678901234567890123456789012345678901234567890123456789012345678901234567890",
      .out = & ((const u16) { straightforward_fletcher16_compute("12345678901234567890123456789012345678901234567890123456789012345678901234567890") }),
    },
  };

  return bt_assert_batch(test_vectors, test_fletcher16, bt_fmt_str, bt_fmt_unsigned);
}

static int
t_fletcher16_checksum(void)
{
  struct bt_pair test_vectors[] = {
    {
      .in  = "\001\002",
      .out =  & ((const u16) { straightforward_fletcher16_checksum("\001\002") }),
    },
    {
      .in  = "",
      .out =  & ((const u16) { straightforward_fletcher16_checksum("") }),
    },
    {
      .in  = "a",
      .out =  & ((const u16) { straightforward_fletcher16_checksum("a") }),
    },
    {
      .in  = "abcd",
      .out =  & ((const u16) { straightforward_fletcher16_checksum("abcd") }),
    },
    {
      .in  = "message digest",
      .out =  & ((const u16) { straightforward_fletcher16_checksum("message digest") }),
    },
    {
      .in  = "abcdefghijklmnopqrstuvwxyz",
      .out =  & ((const u16) { straightforward_fletcher16_checksum("abcdefghijklmnopqrstuvwxyz") }),
    },
    {
      .in  = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
      .out =  & ((const u16) { straightforward_fletcher16_checksum("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789") }),
    },
    {
      .in  = "12345678901234567890123456789012345678901234567890123456789012345678901234567890",
      .out =  & ((const u16) { straightforward_fletcher16_checksum("12345678901234567890123456789012345678901234567890123456789012345678901234567890") }),
    },
  };

  return bt_assert_batch(test_vectors, test_fletcher16_checksum, bt_fmt_str, bt_fmt_unsigned);
}

int
main(int argc, char *argv[])
{
  bt_init(argc, argv);

  bt_test_suite(t_fletcher16_compute, "Fletcher-16 Compute Tests");
  bt_test_suite(t_fletcher16_checksum, "Fletcher-16 Checksum Tests");

  return bt_exit_value();
}