diff options
| author | cinap_lenrek <cinap_lenrek@felloff.net> | 2015-12-16 21:18:20 +0100 |
|---|---|---|
| committer | cinap_lenrek <cinap_lenrek@felloff.net> | 2015-12-16 21:18:20 +0100 |
| commit | efd3ac8a2328d1baf55c296a00807052473d549e (patch) | |
| tree | 3e0851312267fee156a3cfb67aea5b4faebbfb76 /sys/include/mp.h | |
| parent | b6f04b77e3d11699d664d0ca7d0ba991f9599acc (diff) | |
libmp: add mpfield() function for fast field arithmetic
instead of testing for special field primes each time in mpmod(),
make it explicit with a mpfiled() function that tests a modulus N
to be of some special form that can be reduced more efficiently with
some precalculation, and replaces N with a Mfield* when it can. the
Mfield*'s are recognized by mpmod() as they have the MPfield flag
set and provide a function pointer that executes the fast reduction.
Diffstat (limited to 'sys/include/mp.h')
| -rw-r--r-- | sys/include/mp.h | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/sys/include/mp.h b/sys/include/mp.h index 31e4ef3d8..f883712de 100644 --- a/sys/include/mp.h +++ b/sys/include/mp.h @@ -8,7 +8,6 @@ * mpdigit must be an atomic type. mpdigit is defined * in the architecture specific u.h */ - typedef struct mpint mpint; struct mpint @@ -25,6 +24,7 @@ enum MPstatic= 0x01, /* static constant */ MPnorm= 0x02, /* normalization status */ MPtimesafe= 0x04, /* request time invariant computation */ + MPfield= 0x08, /* this mpint is a field modulus */ Dbytes= sizeof(mpdigit), /* bytes per digit */ Dbits= Dbytes*8 /* bits per digit */ @@ -165,5 +165,18 @@ void crtout(CRTpre*, CRTres*, mpint*); /* convert residues to mpint */ void crtprefree(CRTpre*); void crtresfree(CRTres*); +/* fast field arithmetic */ +typedef struct Mfield Mfield; + +struct Mfield +{ + mpint; + int (*reduce)(Mfield*, mpint*, mpint*); +}; + +mpint *mpfield(mpint*); + +Mfield *gmfield(mpint*); +Mfield *cnfield(mpint*); #pragma varargck type "B" mpint* |