lib/mpi: mpi_read_buffer(): replace open coded endian conversion

Currently, the endian conversion from CPU order to BE is open coded in
mpi_read_buffer().

Replace this by the centrally provided cpu_to_be*() macros.
Copy from the temporary storage on stack to the destination buffer
by means of memcpy().

Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Nicolai Stange 2016-03-22 13:12:41 +01:00 committed by Herbert Xu
parent f00fa2417b
commit 90f864e200

View File

@ -21,6 +21,7 @@
#include <linux/bitops.h>
#include <linux/count_zeros.h>
#include <linux/byteorder/generic.h>
#include <linux/string.h>
#include "mpi-internal.h"
#define MAX_EXTERN_MPI_BITS 16384
@ -164,7 +165,13 @@ int mpi_read_buffer(MPI a, uint8_t *buf, unsigned buf_len, unsigned *nbytes,
int *sign)
{
uint8_t *p;
mpi_limb_t alimb;
#if BYTES_PER_MPI_LIMB == 4
__be32 alimb;
#elif BYTES_PER_MPI_LIMB == 8
__be64 alimb;
#else
#error please implement for this limb size.
#endif
unsigned int n = mpi_get_size(a);
int i, lzeros;
@ -187,25 +194,15 @@ int mpi_read_buffer(MPI a, uint8_t *buf, unsigned buf_len, unsigned *nbytes,
for (i = a->nlimbs - 1 - lzeros / BYTES_PER_MPI_LIMB,
lzeros %= BYTES_PER_MPI_LIMB;
i >= 0; i--) {
alimb = a->d[i];
#if BYTES_PER_MPI_LIMB == 4
*p++ = alimb >> 24;
*p++ = alimb >> 16;
*p++ = alimb >> 8;
*p++ = alimb;
alimb = cpu_to_be32(a->d[i]);
#elif BYTES_PER_MPI_LIMB == 8
*p++ = alimb >> 56;
*p++ = alimb >> 48;
*p++ = alimb >> 40;
*p++ = alimb >> 32;
*p++ = alimb >> 24;
*p++ = alimb >> 16;
*p++ = alimb >> 8;
*p++ = alimb;
alimb = cpu_to_be64(a->d[i]);
#else
#error please implement for this limb size.
#endif
memcpy(p, &alimb, BYTES_PER_MPI_LIMB);
p += BYTES_PER_MPI_LIMB;
if (lzeros > 0) {
mpi_limb_t *limb1 = (void *)p - sizeof(alimb);
mpi_limb_t *limb2 = (void *)p - sizeof(alimb)