diff options
author | Matt Johnston <matt@ucc.asn.au> | 2006-03-08 13:23:58 +0000 |
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committer | Matt Johnston <matt@ucc.asn.au> | 2006-03-08 13:23:58 +0000 |
commit | 6ae3a09ef33b62811a7f60a1f97dcb89907c1ac1 (patch) | |
tree | 37e84722c5b30bbfc86947bee260473d4604b616 /libtommath/bn_mp_read_unsigned_bin.c | |
parent | 33defd1f9b6c4889fe5b075e6abb0b24c00f3a59 (diff) | |
parent | 8608a8e64c1aeda096867f43f89e29e1aee207ae (diff) |
propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 20dccfc09627970a312d77fb41dc2970b62689c3)
to branch 'au.asn.ucc.matt.dropbear' (head fdf4a7a3b97ae5046139915de7e40399cceb2c01)
--HG--
extra : convert_revision : dc4809882e1b9f2dcd3f8bbe38c74a0a52c39ce4
Diffstat (limited to 'libtommath/bn_mp_read_unsigned_bin.c')
-rw-r--r-- | libtommath/bn_mp_read_unsigned_bin.c | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/libtommath/bn_mp_read_unsigned_bin.c b/libtommath/bn_mp_read_unsigned_bin.c new file mode 100644 index 0000000..946457d --- /dev/null +++ b/libtommath/bn_mp_read_unsigned_bin.c @@ -0,0 +1,52 @@ +#include <tommath.h> +#ifdef BN_MP_READ_UNSIGNED_BIN_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, tomstdenis@iahu.ca, http://math.libtomcrypt.org + */ + +/* reads a unsigned char array, assumes the msb is stored first [big endian] */ +int +mp_read_unsigned_bin (mp_int * a, unsigned char *b, int c) +{ + int res; + + /* make sure there are at least two digits */ + if (a->alloc < 2) { + if ((res = mp_grow(a, 2)) != MP_OKAY) { + return res; + } + } + + /* zero the int */ + mp_zero (a); + + /* read the bytes in */ + while (c-- > 0) { + if ((res = mp_mul_2d (a, 8, a)) != MP_OKAY) { + return res; + } + +#ifndef MP_8BIT + a->dp[0] |= *b++; + a->used += 1; +#else + a->dp[0] = (*b & MP_MASK); + a->dp[1] |= ((*b++ >> 7U) & 1); + a->used += 2; +#endif + } + mp_clamp (a); + return MP_OKAY; +} +#endif |