Mercurial > dropbear
view libtommath/bn_mp_fread.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_FREAD_C /* LibTomMath, multiple-precision integer library -- Tom St Denis */ /* SPDX-License-Identifier: Unlicense */ #ifndef MP_NO_FILE /* read a bigint from a file stream in ASCII */ mp_err mp_fread(mp_int *a, int radix, FILE *stream) { mp_err err; mp_sign neg; /* if first digit is - then set negative */ int ch = fgetc(stream); if (ch == (int)'-') { neg = MP_NEG; ch = fgetc(stream); } else { neg = MP_ZPOS; } /* no digits, return error */ if (ch == EOF) { return MP_ERR; } /* clear a */ mp_zero(a); do { int y; unsigned pos = (unsigned)(ch - (int)'('); if (mp_s_rmap_reverse_sz < pos) { break; } y = (int)mp_s_rmap_reverse[pos]; if ((y == 0xff) || (y >= radix)) { break; } /* shift up and add */ if ((err = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) { return err; } if ((err = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) { return err; } } while ((ch = fgetc(stream)) != EOF); if (a->used != 0) { a->sign = neg; } return MP_OKAY; } #endif #endif