Mercurial > dropbear
view libtommath/bn_mp_expt_d_ex.c @ 1665:7c17995bcdfb
Improve address logging on early exit messages (#83)
Change 'Early exit' and 'Exit before auth' messages to include the IP
address & port as part of the message.
This allows log scanning utilities such as 'fail2ban' to obtain the
offending IP address as part of the failure event instead of extracting
the PID from the message and then scanning the log again for match
'child connection from' messages
Signed-off-by: Kevin Darbyshire-Bryant <[email protected]>
author | Kevin Darbyshire-Bryant <6500011+ldir-EDB0@users.noreply.github.com> |
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date | Wed, 18 Mar 2020 15:28:56 +0000 |
parents | f52919ffd3b1 |
children |
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#include "tommath_private.h" #ifdef BN_MP_EXPT_D_EX_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 */ /* calculate c = a**b using a square-multiply algorithm */ int mp_expt_d_ex(const mp_int *a, mp_digit b, mp_int *c, int fast) { int res; unsigned int x; mp_int g; if ((res = mp_init_copy(&g, a)) != MP_OKAY) { return res; } /* set initial result */ mp_set(c, 1uL); if (fast != 0) { while (b > 0u) { /* if the bit is set multiply */ if ((b & 1u) != 0u) { if ((res = mp_mul(c, &g, c)) != MP_OKAY) { mp_clear(&g); return res; } } /* square */ if (b > 1u) { if ((res = mp_sqr(&g, &g)) != MP_OKAY) { mp_clear(&g); return res; } } /* shift to next bit */ b >>= 1; } } else { for (x = 0; x < (unsigned)DIGIT_BIT; x++) { /* square */ if ((res = mp_sqr(c, c)) != MP_OKAY) { mp_clear(&g); return res; } /* if the bit is set multiply */ if ((b & ((mp_digit)1 << (DIGIT_BIT - 1))) != 0u) { if ((res = mp_mul(c, &g, c)) != MP_OKAY) { mp_clear(&g); return res; } } /* shift to next bit */ b <<= 1; } } /* if ... else */ mp_clear(&g); return MP_OKAY; } #endif /* ref: HEAD -> master, tag: v1.1.0 */ /* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */ /* commit time: 2019-01-28 20:32:32 +0100 */