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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 17:20:00 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 17:20:00 +0000
commit8daa83a594a2e98f39d764422bfbdbc62c9efd44 (patch)
tree4099e8021376c7d8c05bdf8503093d80e9c7bad0 /third_party/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c
parentInitial commit. (diff)
downloadsamba-8daa83a594a2e98f39d764422bfbdbc62c9efd44.tar.xz
samba-8daa83a594a2e98f39d764422bfbdbc62c9efd44.zip
Adding upstream version 2:4.20.0+dfsg.upstream/2%4.20.0+dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c')
-rw-r--r--third_party/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c b/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c
new file mode 100644
index 0000000..a9f4f9f
--- /dev/null
+++ b/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_reduce_is_2k.c
@@ -0,0 +1,38 @@
+#include "tommath_private.h"
+#ifdef BN_MP_REDUCE_IS_2K_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
+
+/* determines if mp_reduce_2k can be used */
+mp_bool mp_reduce_is_2k(const mp_int *a)
+{
+ int ix, iy, iw;
+ mp_digit iz;
+
+ if (a->used == 0) {
+ return MP_NO;
+ } else if (a->used == 1) {
+ return MP_YES;
+ } else if (a->used > 1) {
+ iy = mp_count_bits(a);
+ iz = 1;
+ iw = 1;
+
+ /* Test every bit from the second digit up, must be 1 */
+ for (ix = MP_DIGIT_BIT; ix < iy; ix++) {
+ if ((a->dp[iw] & iz) == 0u) {
+ return MP_NO;
+ }
+ iz <<= 1;
+ if (iz > MP_DIGIT_MAX) {
+ ++iw;
+ iz = 1;
+ }
+ }
+ return MP_YES;
+ } else {
+ return MP_YES;
+ }
+}
+
+#endif