Mercurial > dropbear
view libtommath/bn_mp_mod_2d.c @ 1855:35d504d59c05
Implement server-side support for sk-ecdsa U2F-backed keys (#142)
* Implement server-side support for sk-ecdsa U2F-backed keys
* Fix out-of-bounds read on normal ecdsa-sha2-[identifier] keys
* Fix one more potential out-of-bounds read
* Check if nistp256 curve is used in sk-ecdsa-sha2- key
It's the only allowed curve per PROTOCOL.u2f specification
* Implement server-side support for sk-ed25519 FIDO2-backed keys
* Keys with type sk-* make no sense as host keys, so they should be
disabled
* fix typo
* Make sk-ecdsa call buf_ecdsa_verify
This reduces code duplication, the SK code just handles the
different message format.
* Reduce sk specific code
The application id can be stored in signkey, then we don't need
to call sk-specific functions from svr-authpubkey
* Remove debugging output, which causes compilation errors with DEBUG_TRACE disabled
* Proper cleanup of sk_app
Co-authored-by: Matt Johnston <[email protected]>
author | egor-duda <egor-duda@users.noreply.github.com> |
---|---|
date | Sat, 22 Jan 2022 16:53:04 +0300 |
parents | 1051e4eea25a |
children |
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#include "tommath_private.h" #ifdef BN_MP_MOD_2D_C /* LibTomMath, multiple-precision integer library -- Tom St Denis */ /* SPDX-License-Identifier: Unlicense */ /* calc a value mod 2**b */ mp_err mp_mod_2d(const mp_int *a, int b, mp_int *c) { int x; mp_err err; /* if b is <= 0 then zero the int */ if (b <= 0) { mp_zero(c); return MP_OKAY; } /* if the modulus is larger than the value than return */ if (b >= (a->used * MP_DIGIT_BIT)) { return mp_copy(a, c); } /* copy */ if ((err = mp_copy(a, c)) != MP_OKAY) { return err; } /* zero digits above the last digit of the modulus */ x = (b / MP_DIGIT_BIT) + (((b % MP_DIGIT_BIT) == 0) ? 0 : 1); MP_ZERO_DIGITS(c->dp + x, c->used - x); /* clear the digit that is not completely outside/inside the modulus */ c->dp[b / MP_DIGIT_BIT] &= ((mp_digit)1 << (mp_digit)(b % MP_DIGIT_BIT)) - (mp_digit)1; mp_clamp(c); return MP_OKAY; } #endif