lib/fletcher16_test.c

   1 /*
   2  *      BIRD Library -- Fletcher-16 Tests
   3  *
   4  *      (c) 2015 CZ.NIC z.s.p.o.
   5  *
   6  *      Can be freely distributed and used under the terms of the GNU GPL.
   7  */
   8
   9 #include "test/birdtest.h"
  10 #include "lib/fletcher16.h"
  11
  12 static u16
  13 straightforward_fletcher16_compute(const char *data)
  14 {
  15   int count = strlen(data);
  16
  17   u16 sum1 = 0;
  18   u16 sum2 = 0;
  19   int index;
  20
  21   for (index = 0; index < count; ++index)
  22   {
  23     sum1 = (sum1 + data[index]) % 255;
  24     sum2 = (sum2 + sum1) % 255;
  25   }
  26
  27   return (sum2 << 8) | sum1;
  28 }
  29
  30 static u16
  31 straightforward_fletcher16_checksum(const char *data)
  32 {
  33   u16 csum;
  34   u8 c0,c1,f0,f1;
  35
  36   csum = straightforward_fletcher16_compute(data);
  37   f0 = csum & 0xff;
  38   f1 = (csum >> 8) & 0xff;
  39   c0 = 0xff - ((f0 + f1) % 0xff);
  40   c1 = 0xff - ((f0 + c0) % 0xff);
  41
  42   return (c1 << 8) | c0;
  43 }
  44
  45 static int
  46 test_fletcher16(void *out_, const void *in_, const void *expected_out_)
  47 {
  48   u16 *out = out_;
  49   const char *in = in_;
  50   const u16 *expected_out = expected_out_;
  51
  52   struct fletcher16_context ctxt;
  53
  54   fletcher16_init(&ctxt);
  55   fletcher16_update(&ctxt, in, strlen(in));
  56   put_u16(out, fletcher16_compute(&ctxt));
  57
  58   return *out == *expected_out;
  59 }
  60
  61 static int
  62 test_fletcher16_checksum(void *out_, const void *in_, const void *expected_out_)
  63 {
  64   u16 *out = out_;
  65   const char *in = in_;
  66   const u16 *expected_out = expected_out_;
  67
  68   struct fletcher16_context ctxt;
  69   int len = strlen(in);
  70
  71   fletcher16_init(&ctxt);
  72   fletcher16_update(&ctxt, in, len);
  73   put_u16(out, fletcher16_final(&ctxt, len, len));
  74
  75   return *out == *expected_out;
  76 }
  77
  78 static int
  79 t_fletcher16_compute(void)
  80 {
  81   struct bt_pair test_vectors[] = {
  82     {
  83       .in  = "\001\002",
  84       .out = & (const u16) { 0x0403 },
  85     },
  86     {
  87       .in  = "",
  88       .out = & ((const u16) { straightforward_fletcher16_compute("") }),
  89     },
  90     {
  91       .in  = "a",
  92       .out = & ((const u16) { straightforward_fletcher16_compute("a") }),
  93     },
  94     {
  95       .in  = "abcd",
  96       .out = & ((const u16) { straightforward_fletcher16_compute("abcd") }),
  97     },
  98     {
  99       .in  = "message digest",
 100       .out = & ((const u16) { straightforward_fletcher16_compute("message digest") }),
 101     },
 102     {
 103       .in  = "abcdefghijklmnopqrstuvwxyz",
 104       .out = & ((const u16) { straightforward_fletcher16_compute("abcdefghijklmnopqrstuvwxyz") }),
 105     },
 106     {
 107       .in  = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
 108       .out = & ((const u16) { straightforward_fletcher16_compute("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789") }),
 109     },
 110     {
 111       .in  = "12345678901234567890123456789012345678901234567890123456789012345678901234567890",
 112       .out = & ((const u16) { straightforward_fletcher16_compute("12345678901234567890123456789012345678901234567890123456789012345678901234567890") }),
 113     },
 114   };
 115
 116   return bt_assert_batch(test_vectors, test_fletcher16, bt_fmt_str, bt_fmt_unsigned);
 117 }
 118
 119 static int
 120 t_fletcher16_checksum(void)
 121 {
 122   struct bt_pair test_vectors[] = {
 123     {
 124       .in  = "\001\002",
 125       .out =  & ((const u16) { straightforward_fletcher16_checksum("\001\002") }),
 126     },
 127     {
 128       .in  = "",
 129       .out =  & ((const u16) { straightforward_fletcher16_checksum("") }),
 130     },
 131     {
 132       .in  = "a",
 133       .out =  & ((const u16) { straightforward_fletcher16_checksum("a") }),
 134     },
 135     {
 136       .in  = "abcd",
 137       .out =  & ((const u16) { straightforward_fletcher16_checksum("abcd") }),
 138     },
 139     {
 140       .in  = "message digest",
 141       .out =  & ((const u16) { straightforward_fletcher16_checksum("message digest") }),
 142     },
 143     {
 144       .in  = "abcdefghijklmnopqrstuvwxyz",
 145       .out =  & ((const u16) { straightforward_fletcher16_checksum("abcdefghijklmnopqrstuvwxyz") }),
 146     },
 147     {
 148       .in  = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
 149       .out =  & ((const u16) { straightforward_fletcher16_checksum("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789") }),
 150     },
 151     {
 152       .in  = "12345678901234567890123456789012345678901234567890123456789012345678901234567890",
 153       .out =  & ((const u16) { straightforward_fletcher16_checksum("12345678901234567890123456789012345678901234567890123456789012345678901234567890") }),
 154     },
 155   };
 156
 157   return bt_assert_batch(test_vectors, test_fletcher16_checksum, bt_fmt_str, bt_fmt_unsigned);
 158 }
 159
 160 int
 161 main(int argc, char *argv[])
 162 {
 163   bt_init(argc, argv);
 164
 165   bt_test_suite(t_fletcher16_compute, "Fletcher-16 Compute Tests");
 166   bt_test_suite(t_fletcher16_checksum, "Fletcher-16 Checksum Tests");
 167
 168   return bt_exit_value();
 169 }