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-rw-r--r--libtommath/bn_mp_prime_is_prime.c105
1 files changed, 25 insertions, 80 deletions
diff --git a/libtommath/bn_mp_prime_is_prime.c b/libtommath/bn_mp_prime_is_prime.c
index 6af5c2c..7f9fc0b 100644
--- a/libtommath/bn_mp_prime_is_prime.c
+++ b/libtommath/bn_mp_prime_is_prime.c
@@ -1,16 +1,7 @@
#include "tommath_private.h"
#ifdef BN_MP_PRIME_IS_PRIME_C
-/* LibTomMath, multiple-precision integer library -- Tom St Denis
- *
- * LibTomMath is a library that provides multiple-precision
- * integer arithmetic as well as number theoretic functionality.
- *
- * The library was designed directly after the MPI library by
- * Michael Fromberger but has been written from scratch with
- * additional optimizations in place.
- *
- * SPDX-License-Identifier: Unlicense
- */
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
/* portable integer log of two with small footprint */
static unsigned int s_floor_ilog2(int value)
@@ -23,61 +14,58 @@ static unsigned int s_floor_ilog2(int value)
}
-int mp_prime_is_prime(const mp_int *a, int t, int *result)
+mp_err mp_prime_is_prime(const mp_int *a, int t, mp_bool *result)
{
mp_int b;
- int ix, err, res, p_max = 0, size_a, len;
+ int ix, p_max = 0, size_a, len;
+ mp_bool res;
+ mp_err err;
unsigned int fips_rand, mask;
/* default to no */
*result = MP_NO;
- /* valid value of t? */
- if (t > PRIME_SIZE) {
- return MP_VAL;
- }
-
/* Some shortcuts */
/* N > 3 */
if (a->used == 1) {
if ((a->dp[0] == 0u) || (a->dp[0] == 1u)) {
- *result = 0;
+ *result = MP_NO;
return MP_OKAY;
}
if (a->dp[0] == 2u) {
- *result = 1;
+ *result = MP_YES;
return MP_OKAY;
}
}
/* N must be odd */
- if (mp_iseven(a) == MP_YES) {
+ if (MP_IS_EVEN(a)) {
return MP_OKAY;
}
/* N is not a perfect square: floor(sqrt(N))^2 != N */
if ((err = mp_is_square(a, &res)) != MP_OKAY) {
return err;
}
- if (res != 0) {
+ if (res != MP_NO) {
return MP_OKAY;
}
/* is the input equal to one of the primes in the table? */
- for (ix = 0; ix < PRIME_SIZE; ix++) {
- if (mp_cmp_d(a, ltm_prime_tab[ix]) == MP_EQ) {
+ for (ix = 0; ix < PRIVATE_MP_PRIME_TAB_SIZE; ix++) {
+ if (mp_cmp_d(a, s_mp_prime_tab[ix]) == MP_EQ) {
*result = MP_YES;
return MP_OKAY;
}
}
#ifdef MP_8BIT
/* The search in the loop above was exhaustive in this case */
- if ((a->used == 1) && (PRIME_SIZE >= 31)) {
+ if ((a->used == 1) && (PRIVATE_MP_PRIME_TAB_SIZE >= 31)) {
return MP_OKAY;
}
#endif
/* first perform trial division */
- if ((err = mp_prime_is_divisible(a, &res)) != MP_OKAY) {
+ if ((err = s_mp_prime_is_divisible(a, &res)) != MP_OKAY) {
return err;
}
@@ -114,10 +102,10 @@ int mp_prime_is_prime(const mp_int *a, int t, int *result)
/*
* Both, the Frobenius-Underwood test and the the Lucas-Selfridge test are quite
- * slow so if speed is an issue, define LTM_USE_FIPS_ONLY to use M-R tests with
+ * slow so if speed is an issue, define LTM_USE_ONLY_MR to use M-R tests with
* bases 2, 3 and t random bases.
*/
-#ifndef LTM_USE_FIPS_ONLY
+#ifndef LTM_USE_ONLY_MR
if (t >= 0) {
/*
* Use a Frobenius-Underwood test instead of the Lucas-Selfridge test for
@@ -149,44 +137,14 @@ int mp_prime_is_prime(const mp_int *a, int t, int *result)
}
/*
- abs(t) extra rounds of M-R to extend the range of primes it can find if t < 0.
Only recommended if the input range is known to be < 3317044064679887385961981
- It uses the bases for a deterministic M-R test if input < 3317044064679887385961981
+ It uses the bases necessary for a deterministic M-R test if the input is
+ smaller than 3317044064679887385961981
The caller has to check the size.
-
- Not for cryptographic use because with known bases strong M-R pseudoprimes can
- be constructed. Use at least one M-R test with a random base (t >= 1).
-
- The 1119 bit large number
-
- 80383745745363949125707961434194210813883768828755814583748891752229742737653\
- 33652186502336163960045457915042023603208766569966760987284043965408232928738\
- 79185086916685732826776177102938969773947016708230428687109997439976544144845\
- 34115587245063340927902227529622941498423068816854043264575340183297861112989\
- 60644845216191652872597534901
-
- has been constructed by F. Arnault (F. Arnault, "Rabin-Miller primality test:
- composite numbers which pass it.", Mathematics of Computation, 1995, 64. Jg.,
- Nr. 209, S. 355-361), is a semiprime with the two factors
-
- 40095821663949960541830645208454685300518816604113250877450620473800321707011\
- 96242716223191597219733582163165085358166969145233813917169287527980445796800\
- 452592031836601
-
- 20047910831974980270915322604227342650259408302056625438725310236900160853505\
- 98121358111595798609866791081582542679083484572616906958584643763990222898400\
- 226296015918301
-
- and it is a strong pseudoprime to all forty-six prime M-R bases up to 200
-
- It does not fail the strong Bailley-PSP test as implemented here, it is just
- given as an example, if not the reason to use the BPSW-test instead of M-R-tests
- with a sequence of primes 2...n.
-
+ TODO: can be made a bit finer grained but comparing is not free.
*/
if (t < 0) {
- t = -t;
/*
Sorenson, Jonathan; Webster, Jonathan (2015).
"Strong Pseudoprimes to Twelve Prime Bases".
@@ -212,18 +170,9 @@ int mp_prime_is_prime(const mp_int *a, int t, int *result)
}
}
- /* for compatibility with the current API (well, compatible within a sign's width) */
- if (p_max < t) {
- p_max = t;
- }
-
- if (p_max > PRIME_SIZE) {
- err = MP_VAL;
- goto LBL_B;
- }
/* we did bases 2 and 3 already, skip them */
for (ix = 2; ix < p_max; ix++) {
- mp_set(&b, ltm_prime_tab[ix]);
+ mp_set(&b, s_mp_prime_tab[ix]);
if ((err = mp_prime_miller_rabin(a, &b, &res)) != MP_OKAY) {
goto LBL_B;
}
@@ -296,19 +245,19 @@ int mp_prime_is_prime(const mp_int *a, int t, int *result)
* One 8-bit digit is too small, so concatenate two if the size of
* unsigned int allows for it.
*/
- if (((sizeof(unsigned int) * CHAR_BIT)/2) >= (sizeof(mp_digit) * CHAR_BIT)) {
+ if ((MP_SIZEOF_BITS(unsigned int)/2) >= MP_SIZEOF_BITS(mp_digit)) {
if ((err = mp_rand(&b, 1)) != MP_OKAY) {
goto LBL_B;
}
- fips_rand <<= sizeof(mp_digit) * CHAR_BIT;
+ fips_rand <<= MP_SIZEOF_BITS(mp_digit);
fips_rand |= (unsigned int) b.dp[0];
fips_rand &= mask;
}
#endif
- if (fips_rand > (unsigned int)(INT_MAX - DIGIT_BIT)) {
- len = INT_MAX / DIGIT_BIT;
+ if (fips_rand > (unsigned int)(INT_MAX - MP_DIGIT_BIT)) {
+ len = INT_MAX / MP_DIGIT_BIT;
} else {
- len = (((int)fips_rand + DIGIT_BIT) / DIGIT_BIT);
+ len = (((int)fips_rand + MP_DIGIT_BIT) / MP_DIGIT_BIT);
}
/* Unlikely. */
if (len < 0) {
@@ -363,7 +312,3 @@ LBL_B:
}
#endif
-
-/* ref: HEAD -> master, tag: v1.1.0 */
-/* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
-/* commit time: 2019-01-28 20:32:32 +0100 */