Mercurial > dropbear
view libtommath/bn_mp_mul_2d.c @ 1629:258b57b208ae
Fix for issue successfull login of disabled user (#78)
This commit introduces fix for scenario:
1. Root login disabled on dropbear
2. PAM authentication model enabled
While login as root user, after prompt for password
user is being notified about login failrue, but
after second attempt of prompt for password within
same session, login becames succesfull.
Signed-off-by: Pawel Rapkiewicz <[email protected]>
author | vincentto13 <33652988+vincentto13@users.noreply.github.com> |
---|---|
date | Wed, 20 Mar 2019 15:03:40 +0100 |
parents | 8bba51a55704 |
children | f52919ffd3b1 |
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#include <tommath_private.h> #ifdef BN_MP_MUL_2D_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. * * The library is free for all purposes without any express * guarantee it works. * * Tom St Denis, [email protected], http://libtom.org */ /* shift left by a certain bit count */ int mp_mul_2d (mp_int * a, int b, mp_int * c) { mp_digit d; int res; /* copy */ if (a != c) { if ((res = mp_copy (a, c)) != MP_OKAY) { return res; } } if (c->alloc < (int)(c->used + (b / DIGIT_BIT) + 1)) { if ((res = mp_grow (c, c->used + (b / DIGIT_BIT) + 1)) != MP_OKAY) { return res; } } /* shift by as many digits in the bit count */ if (b >= (int)DIGIT_BIT) { if ((res = mp_lshd (c, b / DIGIT_BIT)) != MP_OKAY) { return res; } } /* shift any bit count < DIGIT_BIT */ d = (mp_digit) (b % DIGIT_BIT); if (d != 0) { mp_digit *tmpc, shift, mask, r, rr; int x; /* bitmask for carries */ mask = (((mp_digit)1) << d) - 1; /* shift for msbs */ shift = DIGIT_BIT - d; /* alias */ tmpc = c->dp; /* carry */ r = 0; for (x = 0; x < c->used; x++) { /* get the higher bits of the current word */ rr = (*tmpc >> shift) & mask; /* shift the current word and OR in the carry */ *tmpc = ((*tmpc << d) | r) & MP_MASK; ++tmpc; /* set the carry to the carry bits of the current word */ r = rr; } /* set final carry */ if (r != 0) { c->dp[(c->used)++] = r; } } mp_clamp (c); return MP_OKAY; } #endif /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */