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authorSteffen Jaeckel <s_jaeckel@gmx.de>2019-09-16 15:50:38 +0200
committerMatt Johnston <matt@ucc.asn.au>2019-09-16 21:50:38 +0800
commit615ed4e46a52b6bfe0bfc581b8c2fbcc6cc488d1 (patch)
tree12b2ba29ae4c42fc65d64d43968c5d03ab3f4452 /libtommath/bn_mp_karatsuba_sqr.c
parentfa116e983b4931010e1082dd5c8bf38bbc77718c (diff)
update ltm to 1.1.0 and enable FIPS 186.4 compliant key-generation (#79)
* make key-generation compliant to FIPS 186.4 * fix includes in tommath_class.h * update fuzzcorpus instead of error-out * fixup fuzzing make-targets * update Makefile.in * apply necessary patches to ltm sources * clean-up not required ltm files * update to vanilla ltm 1.1.0 this already only contains the required files * remove set/get double
Diffstat (limited to 'libtommath/bn_mp_karatsuba_sqr.c')
-rw-r--r--libtommath/bn_mp_karatsuba_sqr.c205
1 files changed, 104 insertions, 101 deletions
diff --git a/libtommath/bn_mp_karatsuba_sqr.c b/libtommath/bn_mp_karatsuba_sqr.c
index 764e85a..dd87314 100644
--- a/libtommath/bn_mp_karatsuba_sqr.c
+++ b/libtommath/bn_mp_karatsuba_sqr.c
@@ -1,4 +1,4 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
#ifdef BN_MP_KARATSUBA_SQR_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis
*
@@ -9,113 +9,116 @@
* Michael Fromberger but has been written from scratch with
* additional optimizations in place.
*
- * The library is free for all purposes without any express
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
+ * SPDX-License-Identifier: Unlicense
*/
-/* Karatsuba squaring, computes b = a*a using three
+/* Karatsuba squaring, computes b = a*a using three
* half size squarings
*
- * See comments of karatsuba_mul for details. It
- * is essentially the same algorithm but merely
+ * See comments of karatsuba_mul for details. It
+ * is essentially the same algorithm but merely
* tuned to perform recursive squarings.
*/
-int mp_karatsuba_sqr (mp_int * a, mp_int * b)
+int mp_karatsuba_sqr(const mp_int *a, mp_int *b)
{
- mp_int x0, x1, t1, t2, x0x0, x1x1;
- int B, err;
-
- err = MP_MEM;
-
- /* min # of digits */
- B = a->used;
-
- /* now divide in two */
- B = B >> 1;
-
- /* init copy all the temps */
- if (mp_init_size (&x0, B) != MP_OKAY)
- goto ERR;
- if (mp_init_size (&x1, a->used - B) != MP_OKAY)
- goto X0;
-
- /* init temps */
- if (mp_init_size (&t1, a->used * 2) != MP_OKAY)
- goto X1;
- if (mp_init_size (&t2, a->used * 2) != MP_OKAY)
- goto T1;
- if (mp_init_size (&x0x0, B * 2) != MP_OKAY)
- goto T2;
- if (mp_init_size (&x1x1, (a->used - B) * 2) != MP_OKAY)
- goto X0X0;
-
- {
- int x;
- mp_digit *dst, *src;
-
- src = a->dp;
-
- /* now shift the digits */
- dst = x0.dp;
- for (x = 0; x < B; x++) {
- *dst++ = *src++;
- }
-
- dst = x1.dp;
- for (x = B; x < a->used; x++) {
- *dst++ = *src++;
- }
- }
-
- x0.used = B;
- x1.used = a->used - B;
-
- mp_clamp (&x0);
-
- /* now calc the products x0*x0 and x1*x1 */
- if (mp_sqr (&x0, &x0x0) != MP_OKAY)
- goto X1X1; /* x0x0 = x0*x0 */
- if (mp_sqr (&x1, &x1x1) != MP_OKAY)
- goto X1X1; /* x1x1 = x1*x1 */
-
- /* now calc (x1+x0)**2 */
- if (s_mp_add (&x1, &x0, &t1) != MP_OKAY)
- goto X1X1; /* t1 = x1 - x0 */
- if (mp_sqr (&t1, &t1) != MP_OKAY)
- goto X1X1; /* t1 = (x1 - x0) * (x1 - x0) */
-
- /* add x0y0 */
- if (s_mp_add (&x0x0, &x1x1, &t2) != MP_OKAY)
- goto X1X1; /* t2 = x0x0 + x1x1 */
- if (s_mp_sub (&t1, &t2, &t1) != MP_OKAY)
- goto X1X1; /* t1 = (x1+x0)**2 - (x0x0 + x1x1) */
-
- /* shift by B */
- if (mp_lshd (&t1, B) != MP_OKAY)
- goto X1X1; /* t1 = (x0x0 + x1x1 - (x1-x0)*(x1-x0))<<B */
- if (mp_lshd (&x1x1, B * 2) != MP_OKAY)
- goto X1X1; /* x1x1 = x1x1 << 2*B */
-
- if (mp_add (&x0x0, &t1, &t1) != MP_OKAY)
- goto X1X1; /* t1 = x0x0 + t1 */
- if (mp_add (&t1, &x1x1, b) != MP_OKAY)
- goto X1X1; /* t1 = x0x0 + t1 + x1x1 */
-
- err = MP_OKAY;
-
-X1X1:mp_clear (&x1x1);
-X0X0:mp_clear (&x0x0);
-T2:mp_clear (&t2);
-T1:mp_clear (&t1);
-X1:mp_clear (&x1);
-X0:mp_clear (&x0);
-ERR:
- return err;
+ mp_int x0, x1, t1, t2, x0x0, x1x1;
+ int B, err;
+
+ err = MP_MEM;
+
+ /* min # of digits */
+ B = a->used;
+
+ /* now divide in two */
+ B = B >> 1;
+
+ /* init copy all the temps */
+ if (mp_init_size(&x0, B) != MP_OKAY)
+ goto LBL_ERR;
+ if (mp_init_size(&x1, a->used - B) != MP_OKAY)
+ goto X0;
+
+ /* init temps */
+ if (mp_init_size(&t1, a->used * 2) != MP_OKAY)
+ goto X1;
+ if (mp_init_size(&t2, a->used * 2) != MP_OKAY)
+ goto T1;
+ if (mp_init_size(&x0x0, B * 2) != MP_OKAY)
+ goto T2;
+ if (mp_init_size(&x1x1, (a->used - B) * 2) != MP_OKAY)
+ goto X0X0;
+
+ {
+ int x;
+ mp_digit *dst, *src;
+
+ src = a->dp;
+
+ /* now shift the digits */
+ dst = x0.dp;
+ for (x = 0; x < B; x++) {
+ *dst++ = *src++;
+ }
+
+ dst = x1.dp;
+ for (x = B; x < a->used; x++) {
+ *dst++ = *src++;
+ }
+ }
+
+ x0.used = B;
+ x1.used = a->used - B;
+
+ mp_clamp(&x0);
+
+ /* now calc the products x0*x0 and x1*x1 */
+ if (mp_sqr(&x0, &x0x0) != MP_OKAY)
+ goto X1X1; /* x0x0 = x0*x0 */
+ if (mp_sqr(&x1, &x1x1) != MP_OKAY)
+ goto X1X1; /* x1x1 = x1*x1 */
+
+ /* now calc (x1+x0)**2 */
+ if (s_mp_add(&x1, &x0, &t1) != MP_OKAY)
+ goto X1X1; /* t1 = x1 - x0 */
+ if (mp_sqr(&t1, &t1) != MP_OKAY)
+ goto X1X1; /* t1 = (x1 - x0) * (x1 - x0) */
+
+ /* add x0y0 */
+ if (s_mp_add(&x0x0, &x1x1, &t2) != MP_OKAY)
+ goto X1X1; /* t2 = x0x0 + x1x1 */
+ if (s_mp_sub(&t1, &t2, &t1) != MP_OKAY)
+ goto X1X1; /* t1 = (x1+x0)**2 - (x0x0 + x1x1) */
+
+ /* shift by B */
+ if (mp_lshd(&t1, B) != MP_OKAY)
+ goto X1X1; /* t1 = (x0x0 + x1x1 - (x1-x0)*(x1-x0))<<B */
+ if (mp_lshd(&x1x1, B * 2) != MP_OKAY)
+ goto X1X1; /* x1x1 = x1x1 << 2*B */
+
+ if (mp_add(&x0x0, &t1, &t1) != MP_OKAY)
+ goto X1X1; /* t1 = x0x0 + t1 */
+ if (mp_add(&t1, &x1x1, b) != MP_OKAY)
+ goto X1X1; /* t1 = x0x0 + t1 + x1x1 */
+
+ err = MP_OKAY;
+
+X1X1:
+ mp_clear(&x1x1);
+X0X0:
+ mp_clear(&x0x0);
+T2:
+ mp_clear(&t2);
+T1:
+ mp_clear(&t1);
+X1:
+ mp_clear(&x1);
+X0:
+ mp_clear(&x0);
+LBL_ERR:
+ return err;
}
#endif
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */
+/* ref: HEAD -> master, tag: v1.1.0 */
+/* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
+/* commit time: 2019-01-28 20:32:32 +0100 */