Mercurial > dropbear
view libtommath/bn_mp_expt_u32.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_EXPT_U32_C /* LibTomMath, multiple-precision integer library -- Tom St Denis */ /* SPDX-License-Identifier: Unlicense */ /* calculate c = a**b using a square-multiply algorithm */ mp_err mp_expt_u32(const mp_int *a, uint32_t b, mp_int *c) { mp_err err; mp_int g; if ((err = mp_init_copy(&g, a)) != MP_OKAY) { return err; } /* set initial result */ mp_set(c, 1uL); while (b > 0u) { /* if the bit is set multiply */ if ((b & 1u) != 0u) { if ((err = mp_mul(c, &g, c)) != MP_OKAY) { goto LBL_ERR; } } /* square */ if (b > 1u) { if ((err = mp_sqr(&g, &g)) != MP_OKAY) { goto LBL_ERR; } } /* shift to next bit */ b >>= 1; } err = MP_OKAY; LBL_ERR: mp_clear(&g); return err; } #endif