31 lines
699 B
C
31 lines
699 B
C
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#include "tommath_private.h"
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#ifdef MP_FROM_UBIN_C
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/* LibTomMath, multiple-precision integer library -- Tom St Denis */
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/* SPDX-License-Identifier: Unlicense */
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/* reads a uint8_t array, assumes the msb is stored first [big endian] */
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mp_err mp_from_ubin(mp_int *a, const uint8_t *buf, size_t size)
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{
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mp_err err;
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/* make sure there are at least two digits */
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if ((err = mp_grow(a, 2)) != MP_OKAY) {
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return err;
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}
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/* zero the int */
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mp_zero(a);
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/* read the bytes in */
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while (size-- > 0u) {
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if ((err = mp_mul_2d(a, 8, a)) != MP_OKAY) {
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return err;
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}
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a->dp[0] |= *buf++;
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a->used += 1;
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}
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mp_clamp(a);
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return MP_OKAY;
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}
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#endif
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