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-rw-r--r--crypto/math/stat.c367
1 files changed, 0 insertions, 367 deletions
diff --git a/crypto/math/stat.c b/crypto/math/stat.c
deleted file mode 100644
index 5e46c20..0000000
--- a/crypto/math/stat.c
+++ /dev/null
@@ -1,367 +0,0 @@
-/*
- * stats.c
- *
- * statistical tests for randomness (FIPS 140-2, Section 4.9)
- *
- * David A. McGrew
- * Cisco Systems, Inc.
- */
-
-#include "stat.h"
-
-debug_module_t mod_stat = {
- 0, /* debugging is off by default */
- (char *)"stat test" /* printable module name */
-};
-
-/*
- * each test assumes that 20,000 bits (2500 octets) of data is
- * provided as input
- */
-
-#define STAT_TEST_DATA_LEN 2500
-
-err_status_t
-stat_test_monobit(uint8_t *data) {
- uint8_t *data_end = data + STAT_TEST_DATA_LEN;
- uint16_t ones_count;
-
- ones_count = 0;
- while (data < data_end) {
- ones_count += octet_get_weight(*data);
- data++;
- }
-
- debug_print(mod_stat, "bit count: %d", ones_count);
-
- if ((ones_count < 9725) || (ones_count > 10275))
- return err_status_algo_fail;
-
- return err_status_ok;
-}
-
-err_status_t
-stat_test_poker(uint8_t *data) {
- int i;
- uint8_t *data_end = data + STAT_TEST_DATA_LEN;
- double poker;
- uint16_t f[16] = {
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0
- };
-
- while (data < data_end) {
- f[*data & 0x0f]++; /* increment freq. count for low nibble */
- f[(*data) >> 4]++; /* increment freq. count for high nibble */
- data++;
- }
-
- poker = 0.0;
- for (i=0; i < 16; i++)
- poker += (double) f[i] * f[i];
-
- poker *= (16.0 / 5000.0);
- poker -= 5000.0;
-
- debug_print(mod_stat, "poker test: %f\n", poker);
-
- if ((poker < 2.16) || (poker > 46.17))
- return err_status_algo_fail;
-
- return err_status_ok;
-}
-
-
-/*
- * runs[i] holds the number of runs of size (i-1)
- */
-
-err_status_t
-stat_test_runs(uint8_t *data) {
- uint8_t *data_end = data + STAT_TEST_DATA_LEN;
- uint16_t runs[6] = { 0, 0, 0, 0, 0, 0 };
- uint16_t gaps[6] = { 0, 0, 0, 0, 0, 0 };
- uint16_t lo_value[6] = { 2315, 1114, 527, 240, 103, 103 };
- uint16_t hi_value[6] = { 2685, 1386, 723, 384, 209, 209 };
- int state = 0;
- uint16_t mask;
- int i;
-
- /*
- * the state variable holds the number of bits in the
- * current run (or gap, if negative)
- */
-
- while (data < data_end) {
-
- /* loop over the bits of this byte */
- for (mask = 1; mask < 256; mask <<= 1) {
- if (*data & mask) {
-
- /* next bit is a one */
- if (state > 0) {
-
- /* prefix is a run, so increment the run-count */
- state++;
-
- /* check for long runs */
- if (state > 25) {
- debug_print(mod_stat, ">25 runs: %d", state);
- return err_status_algo_fail;
- }
-
- } else if (state < 0) {
-
- /* prefix is a gap */
- if (state < -25) {
- debug_print(mod_stat, ">25 gaps: %d", state);
- return err_status_algo_fail; /* long-runs test failed */
- }
- if (state < -6) {
- state = -6; /* group together gaps > 5 */
- }
- gaps[-1-state]++; /* increment gap count */
- state = 1; /* set state at one set bit */
- } else {
-
- /* state is zero; this happens only at initialization */
- state = 1;
- }
- } else {
-
- /* next bit is a zero */
- if (state > 0) {
-
- /* prefix is a run */
- if (state > 25) {
- debug_print(mod_stat, ">25 runs (2): %d", state);
- return err_status_algo_fail; /* long-runs test failed */
- }
- if (state > 6) {
- state = 6; /* group together runs > 5 */
- }
- runs[state-1]++; /* increment run count */
- state = -1; /* set state at one zero bit */
- } else if (state < 0) {
-
- /* prefix is a gap, so increment gap-count (decrement state) */
- state--;
-
- /* check for long gaps */
- if (state < -25) {
- debug_print(mod_stat, ">25 gaps (2): %d", state);
- return err_status_algo_fail;
- }
-
- } else {
-
- /* state is zero; this happens only at initialization */
- state = -1;
- }
- }
- }
-
- /* move along to next octet */
- data++;
- }
-
- if (mod_stat.on) {
- debug_print(mod_stat, "runs test", NULL);
- for (i=0; i < 6; i++)
- debug_print(mod_stat, " runs[]: %d", runs[i]);
- for (i=0; i < 6; i++)
- debug_print(mod_stat, " gaps[]: %d", gaps[i]);
- }
-
- /* check run and gap counts against the fixed limits */
- for (i=0; i < 6; i++)
- if ( (runs[i] < lo_value[i] ) || (runs[i] > hi_value[i])
- || (gaps[i] < lo_value[i] ) || (gaps[i] > hi_value[i]))
- return err_status_algo_fail;
-
-
- return err_status_ok;
-}
-
-
-/*
- * the function stat_test_rand_source applys the FIPS-140-2 statistical
- * tests to the random source defined by rs
- *
- */
-
-#define RAND_SRC_BUF_OCTETS 50 /* this value MUST divide 2500! */
-
-err_status_t
-stat_test_rand_source(rand_source_func_t get_rand_bytes) {
- int i;
- double poker;
- uint8_t *data, *data_end;
- uint16_t f[16] = {
- 0, 0, 0, 0, 0, 0, 0, 0,
- 0, 0, 0, 0, 0, 0, 0, 0
- };
- uint8_t buffer[RAND_SRC_BUF_OCTETS];
- err_status_t status;
- int ones_count = 0;
- uint16_t runs[6] = { 0, 0, 0, 0, 0, 0 };
- uint16_t gaps[6] = { 0, 0, 0, 0, 0, 0 };
- uint16_t lo_value[6] = { 2315, 1114, 527, 240, 103, 103 };
- uint16_t hi_value[6] = { 2685, 1386, 723, 384, 209, 209 };
- int state = 0;
- uint16_t mask;
-
- /* counters for monobit, poker, and runs tests are initialized above */
-
- /* main loop: fill buffer, update counters for stat tests */
- for (i=0; i < 2500; i+=RAND_SRC_BUF_OCTETS) {
-
- /* fill data buffer */
- status = get_rand_bytes(buffer, RAND_SRC_BUF_OCTETS);
- if (status) {
- debug_print(mod_stat, "couldn't get rand bytes: %d",status);
- return status;
- }
-
-#if 0
- debug_print(mod_stat, "%s",
- octet_string_hex_string(buffer, RAND_SRC_BUF_OCTETS));
-#endif
-
- data = buffer;
- data_end = data + RAND_SRC_BUF_OCTETS;
- while (data < data_end) {
-
- /* update monobit test counter */
- ones_count += octet_get_weight(*data);
-
- /* update poker test counters */
- f[*data & 0x0f]++; /* increment freq. count for low nibble */
- f[(*data) >> 4]++; /* increment freq. count for high nibble */
-
- /* update runs test counters */
- /* loop over the bits of this byte */
- for (mask = 1; mask < 256; mask <<= 1) {
- if (*data & mask) {
-
- /* next bit is a one */
- if (state > 0) {
-
- /* prefix is a run, so increment the run-count */
- state++;
-
- /* check for long runs */
- if (state > 25) {
- debug_print(mod_stat, ">25 runs (3): %d", state);
- return err_status_algo_fail;
- }
-
- } else if (state < 0) {
-
- /* prefix is a gap */
- if (state < -25) {
- debug_print(mod_stat, ">25 gaps (3): %d", state);
- return err_status_algo_fail; /* long-runs test failed */
- }
- if (state < -6) {
- state = -6; /* group together gaps > 5 */
- }
- gaps[-1-state]++; /* increment gap count */
- state = 1; /* set state at one set bit */
- } else {
-
- /* state is zero; this happens only at initialization */
- state = 1;
- }
- } else {
-
- /* next bit is a zero */
- if (state > 0) {
-
- /* prefix is a run */
- if (state > 25) {
- debug_print(mod_stat, ">25 runs (4): %d", state);
- return err_status_algo_fail; /* long-runs test failed */
- }
- if (state > 6) {
- state = 6; /* group together runs > 5 */
- }
- runs[state-1]++; /* increment run count */
- state = -1; /* set state at one zero bit */
- } else if (state < 0) {
-
- /* prefix is a gap, so increment gap-count (decrement state) */
- state--;
-
- /* check for long gaps */
- if (state < -25) {
- debug_print(mod_stat, ">25 gaps (4): %d", state);
- return err_status_algo_fail;
- }
-
- } else {
-
- /* state is zero; this happens only at initialization */
- state = -1;
- }
- }
- }
-
- /* advance data pointer */
- data++;
- }
- }
-
- /* check to see if test data is within bounds */
-
- /* check monobit test data */
-
- debug_print(mod_stat, "stat: bit count: %d", ones_count);
-
- if ((ones_count < 9725) || (ones_count > 10275)) {
- debug_print(mod_stat, "stat: failed monobit test %d", ones_count);
- return err_status_algo_fail;
- }
-
- /* check poker test data */
- poker = 0.0;
- for (i=0; i < 16; i++)
- poker += (double) f[i] * f[i];
-
- poker *= (16.0 / 5000.0);
- poker -= 5000.0;
-
- debug_print(mod_stat, "stat: poker test: %f", poker);
-
- if ((poker < 2.16) || (poker > 46.17)) {
- debug_print(mod_stat, "stat: failed poker test", NULL);
- return err_status_algo_fail;
- }
-
- /* check run and gap counts against the fixed limits */
- for (i=0; i < 6; i++)
- if ((runs[i] < lo_value[i] ) || (runs[i] > hi_value[i])
- || (gaps[i] < lo_value[i] ) || (gaps[i] > hi_value[i])) {
- debug_print(mod_stat, "stat: failed run/gap test", NULL);
- return err_status_algo_fail;
- }
-
- debug_print(mod_stat, "passed random stat test", NULL);
- return err_status_ok;
-}
-
-err_status_t
-stat_test_rand_source_with_repetition(rand_source_func_t source, unsigned num_trials) {
- unsigned int i;
- err_status_t err = err_status_algo_fail;
-
- for (i=0; i < num_trials; i++) {
- err = stat_test_rand_source(source);
- if (err == err_status_ok) {
- return err_status_ok;
- }
- debug_print(mod_stat, "failed stat test (try number %d)\n", i);
- }
-
- return err;
-}
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