/* This should be made into an inline function in gmp.h. */
void
_gcry_mpih_mul_n( mpi_ptr_t prodp,
mpi_ptr_t up, mpi_ptr_t vp, mpi_size_t size)
{
int secure;
if( up == vp ) {
if( size < KARATSUBA_THRESHOLD )
_gcry_mpih_sqr_n_basecase( prodp, up, size );
else {
mpi_ptr_t tspace;
secure = _gcry_is_secure( up );
tspace = mpi_alloc_limb_space( 2 * size, secure );
_gcry_mpih_sqr_n( prodp, up, size, tspace );
_gcry_mpi_free_limb_space (tspace, 2 * size );
}
}
else {
if( size < KARATSUBA_THRESHOLD )
mul_n_basecase( prodp, up, vp, size );
else {
mpi_ptr_t tspace;
secure = _gcry_is_secure( up ) || _gcry_is_secure( vp );
tspace = mpi_alloc_limb_space( 2 * size, secure );
mul_n (prodp, up, vp, size, tspace);
_gcry_mpi_free_limb_space (tspace, 2 * size );
}
}
}
/****************
* Note: This copy function should not interpret the MPI
* but copy it transparently.
*/
gcry_mpi_t
_gcry_mpi_copy (gcry_mpi_t a)
{
int i;
gcry_mpi_t b;
if( a && (a->flags & 4) ) {
void *p = _gcry_is_secure(a->d)? xmalloc_secure ((a->sign+7)/8)
: xmalloc ((a->sign+7)/8);
memcpy( p, a->d, (a->sign+7)/8 );
b = mpi_set_opaque( NULL, p, a->sign );
b->flags &= ~(16|32); /* Reset the immutable and constant flags. */
}
else if( a ) {
b = mpi_is_secure(a)? mpi_alloc_secure( a->nlimbs )
: mpi_alloc( a->nlimbs );
b->nlimbs = a->nlimbs;
b->sign = a->sign;
b->flags = a->flags;
b->flags &= ~(16|32); /* Reset the immutable and constant flags. */
for(i=0; i < b->nlimbs; i++ )
b->d[i] = a->d[i];
}
else
b = NULL;
return b;
}
gcry_mpi_t
_gcry_mpi_set_opaque (gcry_mpi_t a, void *p, unsigned int nbits)
{
if (!a)
a = mpi_alloc(0);
if (mpi_is_immutable (a))
{
mpi_immutable_failed ();
return a;
}
if( a->flags & 4 )
xfree (a->d);
else
_gcry_mpi_free_limb_space (a->d, a->alloced);
a->d = p;
a->alloced = 0;
a->nlimbs = 0;
a->sign = nbits;
a->flags = 4 | (a->flags & (GCRYMPI_FLAG_USER1|GCRYMPI_FLAG_USER2
|GCRYMPI_FLAG_USER3|GCRYMPI_FLAG_USER4));
if (_gcry_is_secure (a->d))
a->flags |= 1;
return a;
}
gcry_mpi_t
_gcry_mpi_set_opaque_copy (gcry_mpi_t a, const void *p, unsigned int nbits)
{
void *d;
unsigned int n;
n = (nbits+7)/8;
d = _gcry_is_secure (p)? xtrymalloc_secure (n) : xtrymalloc (n);
if (!d)
return NULL;
memcpy (d, p, n);
return mpi_set_opaque (a, d, nbits);
}
void *
_gcry_mpi_get_opaque_copy (gcry_mpi_t a, unsigned int *nbits)
{
const void *s;
void *d;
unsigned int n;
s = mpi_get_opaque (a, nbits);
if (!s && nbits)
return NULL;
n = (*nbits+7)/8;
d = _gcry_is_secure (s)? xtrymalloc_secure (n) : xtrymalloc (n);
if (d)
memcpy (d, s, n);
return d;
}
/****************
* This function allocates an MPI which is optimized to hold
* a value as large as the one given in the argument and allocates it
* with the same flags as A.
*/
gcry_mpi_t
_gcry_mpi_alloc_like( gcry_mpi_t a )
{
gcry_mpi_t b;
if( a && (a->flags & 4) ) {
int n = (a->sign+7)/8;
void *p = _gcry_is_secure(a->d)? xtrymalloc_secure (n)
: xtrymalloc (n);
memcpy( p, a->d, n );
b = mpi_set_opaque( NULL, p, a->sign );
}
else if( a ) {
b = mpi_is_secure(a)? mpi_alloc_secure( a->nlimbs )
: mpi_alloc( a->nlimbs );
b->nlimbs = 0;
b->sign = 0;
b->flags = a->flags;
}
else
b = NULL;
return b;
}
int
gcry_is_secure (const void *a)
{
return _gcry_is_secure (a);
}
void
_gcry_mpih_mul_karatsuba_case( mpi_ptr_t prodp,
mpi_ptr_t up, mpi_size_t usize,
mpi_ptr_t vp, mpi_size_t vsize,
struct karatsuba_ctx *ctx )
{
mpi_limb_t cy;
if( !ctx->tspace || ctx->tspace_size < vsize ) {
if( ctx->tspace )
_gcry_mpi_free_limb_space( ctx->tspace, ctx->tspace_nlimbs );
ctx->tspace_nlimbs = 2 * vsize;
ctx->tspace = mpi_alloc_limb_space (2 * vsize,
(_gcry_is_secure (up)
|| _gcry_is_secure (vp)));
ctx->tspace_size = vsize;
}
MPN_MUL_N_RECURSE( prodp, up, vp, vsize, ctx->tspace );
prodp += vsize;
up += vsize;
usize -= vsize;
if( usize >= vsize ) {
if( !ctx->tp || ctx->tp_size < vsize ) {
if( ctx->tp )
_gcry_mpi_free_limb_space( ctx->tp, ctx->tp_nlimbs );
ctx->tp_nlimbs = 2 * vsize;
ctx->tp = mpi_alloc_limb_space (2 * vsize,
(_gcry_is_secure (up)
|| _gcry_is_secure (vp)));
ctx->tp_size = vsize;
}
do {
MPN_MUL_N_RECURSE( ctx->tp, up, vp, vsize, ctx->tspace );
cy = _gcry_mpih_add_n( prodp, prodp, ctx->tp, vsize );
_gcry_mpih_add_1( prodp + vsize, ctx->tp + vsize, vsize, cy );
prodp += vsize;
up += vsize;
usize -= vsize;
} while( usize >= vsize );
}
if( usize ) {
if( usize < KARATSUBA_THRESHOLD ) {
_gcry_mpih_mul( ctx->tspace, vp, vsize, up, usize );
}
else {
if( !ctx->next ) {
ctx->next = xcalloc( 1, sizeof *ctx );
}
_gcry_mpih_mul_karatsuba_case( ctx->tspace,
vp, vsize,
up, usize,
ctx->next );
}
cy = _gcry_mpih_add_n( prodp, prodp, ctx->tspace, vsize);
_gcry_mpih_add_1( prodp + vsize, ctx->tspace + vsize, usize, cy );
}
}
