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-rw-r--r--third_party/heimdal/lib/hcrypto/libtommath/bn_mp_rand.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_rand.c b/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_rand.c
new file mode 100644
index 0000000..7e9052c
--- /dev/null
+++ b/third_party/heimdal/lib/hcrypto/libtommath/bn_mp_rand.c
@@ -0,0 +1,46 @@
+#include "tommath_private.h"
+#ifdef BN_MP_RAND_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
+
+mp_err(*s_mp_rand_source)(void *out, size_t size) = s_mp_rand_platform;
+
+void mp_rand_source(mp_err(*source)(void *out, size_t size))
+{
+ s_mp_rand_source = (source == NULL) ? s_mp_rand_platform : source;
+}
+
+mp_err mp_rand(mp_int *a, int digits)
+{
+ int i;
+ mp_err err;
+
+ mp_zero(a);
+
+ if (digits <= 0) {
+ return MP_OKAY;
+ }
+
+ if ((err = mp_grow(a, digits)) != MP_OKAY) {
+ return err;
+ }
+
+ if ((err = s_mp_rand_source(a->dp, (size_t)digits * sizeof(mp_digit))) != MP_OKAY) {
+ return err;
+ }
+
+ /* TODO: We ensure that the highest digit is nonzero. Should this be removed? */
+ while ((a->dp[digits - 1] & MP_MASK) == 0u) {
+ if ((err = s_mp_rand_source(a->dp + digits - 1, sizeof(mp_digit))) != MP_OKAY) {
+ return err;
+ }
+ }
+
+ a->used = digits;
+ for (i = 0; i < digits; ++i) {
+ a->dp[i] &= MP_MASK;
+ }
+
+ return MP_OKAY;
+}
+#endif