Mercurial > dropbear
view libtommath/bn_mp_grow.c @ 1861:2b3a8026a6ce
Add re-exec for server
This allows ASLR to re-randomize the address
space for every connection, preventing some
vulnerabilities from being exploitable by
repeated probing.
Overhead (memory and time) is yet to be confirmed.
At present this is only enabled on Linux. Other BSD platforms
with fexecve() would probably also work though have not been tested.
author | Matt Johnston <matt@ucc.asn.au> |
---|---|
date | Sun, 30 Jan 2022 10:14:56 +0800 |
parents | 1051e4eea25a |
children |
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#include "tommath_private.h" #ifdef BN_MP_GROW_C /* LibTomMath, multiple-precision integer library -- Tom St Denis */ /* SPDX-License-Identifier: Unlicense */ /* grow as required */ mp_err mp_grow(mp_int *a, int size) { int i; mp_digit *tmp; /* if the alloc size is smaller alloc more ram */ if (a->alloc < size) { /* reallocate the array a->dp * * We store the return in a temporary variable * in case the operation failed we don't want * to overwrite the dp member of a. */ tmp = (mp_digit *) MP_REALLOC(a->dp, (size_t)a->alloc * sizeof(mp_digit), (size_t)size * sizeof(mp_digit)); if (tmp == NULL) { /* reallocation failed but "a" is still valid [can be freed] */ return MP_MEM; } /* reallocation succeeded so set a->dp */ a->dp = tmp; /* zero excess digits */ i = a->alloc; a->alloc = size; MP_ZERO_DIGITS(a->dp + i, a->alloc - i); } return MP_OKAY; } #endif