Mercurial > dropbear
annotate bn_mp_clear.c @ 163:8e94663164c6 libtommath LTM_DB_0.44
make pointers volatile so that memory zeroing won't get optimised away
| author | Matt Johnston <matt@ucc.asn.au> |
|---|---|
| date | Sun, 02 Jan 2005 17:09:26 +0000 |
| parents | d29b64170cf0 |
| children |
| rev | line source |
|---|---|
| 142 | 1 #include <tommath.h> |
| 2 #ifdef BN_MP_CLEAR_C | |
| 1 | 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis |
| 4 * | |
| 5 * LibTomMath is a library that provides multiple-precision | |
| 6 * integer arithmetic as well as number theoretic functionality. | |
| 7 * | |
| 8 * The library was designed directly after the MPI library by | |
| 9 * Michael Fromberger but has been written from scratch with | |
| 10 * additional optimizations in place. | |
| 11 * | |
| 12 * The library is free for all purposes without any express | |
| 13 * guarantee it works. | |
| 14 * | |
| 15 * Tom St Denis, [email protected], http://math.libtomcrypt.org | |
| 16 */ | |
| 17 | |
| 18 /* clear one (frees) */ | |
| 19 void | |
| 20 mp_clear (mp_int * a) | |
| 21 { | |
|
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8e94663164c6
make pointers volatile so that memory zeroing won't get optimised away
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parents:
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22 volatile mp_digit *p; |
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8e94663164c6
make pointers volatile so that memory zeroing won't get optimised away
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parents:
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23 int len; |
| 142 | 24 |
| 1 | 25 /* only do anything if a hasn't been freed previously */ |
| 26 if (a->dp != NULL) { | |
| 27 /* first zero the digits */ | |
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make pointers volatile so that memory zeroing won't get optimised away
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28 len = a->alloc; |
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make pointers volatile so that memory zeroing won't get optimised away
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29 p = a->dp; |
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30 while (len--) { |
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31 *p++ = 0; |
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8e94663164c6
make pointers volatile so that memory zeroing won't get optimised away
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parents:
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32 } |
| 1 | 33 |
| 34 /* free ram */ | |
| 35 XFREE(a->dp); | |
| 36 | |
| 37 /* reset members to make debugging easier */ | |
| 38 a->dp = NULL; | |
| 39 a->alloc = a->used = 0; | |
| 40 a->sign = MP_ZPOS; | |
| 41 } | |
| 42 } | |
| 142 | 43 #endif |