Mercurial > dropbear
view libtommath/bn_mp_read_radix.c @ 1659:d32bcb5c557d
Add Ed25519 support (#91)
* Add support for Ed25519 as a public key type
Ed25519 is a elliptic curve signature scheme that offers
better security than ECDSA and DSA and good performance. It may be
used for both user and host keys.
OpenSSH key import and fuzzer are not supported yet.
Initially inspired by Peter Szabo.
* Add curve25519 and ed25519 fuzzers
* Add import and export of Ed25519 keys
author | Vladislav Grishenko <themiron@users.noreply.github.com> |
---|---|
date | Wed, 11 Mar 2020 21:09:45 +0500 |
parents | f52919ffd3b1 |
children | 1051e4eea25a |
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#include "tommath_private.h" #ifdef BN_MP_READ_RADIX_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 */ /* read a string [ASCII] in a given radix */ int mp_read_radix(mp_int *a, const char *str, int radix) { int y, res, neg; unsigned pos; char ch; /* zero the digit bignum */ mp_zero(a); /* make sure the radix is ok */ if ((radix < 2) || (radix > 64)) { return MP_VAL; } /* if the leading digit is a * minus set the sign to negative. */ if (*str == '-') { ++str; neg = MP_NEG; } else { neg = MP_ZPOS; } /* set the integer to the default of zero */ mp_zero(a); /* process each digit of the string */ while (*str != '\0') { /* if the radix <= 36 the conversion is case insensitive * this allows numbers like 1AB and 1ab to represent the same value * [e.g. in hex] */ ch = (radix <= 36) ? (char)toupper((int)*str) : *str; pos = (unsigned)(ch - '('); if (mp_s_rmap_reverse_sz < pos) { break; } y = (int)mp_s_rmap_reverse[pos]; /* if the char was found in the map * and is less than the given radix add it * to the number, otherwise exit the loop. */ if ((y == 0xff) || (y >= radix)) { break; } if ((res = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) { return res; } if ((res = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) { return res; } ++str; } /* if an illegal character was found, fail. */ if (!((*str == '\0') || (*str == '\r') || (*str == '\n'))) { mp_zero(a); return MP_VAL; } /* set the sign only if a != 0 */ if (mp_iszero(a) != MP_YES) { a->sign = neg; } return MP_OKAY; } #endif /* ref: HEAD -> master, tag: v1.1.0 */ /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */ /* commit time: 2019-01-28 20:32:32 +0100 */