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Diffstat (limited to 'lib/crypto/mpi/mpi-add.c')
-rw-r--r--lib/crypto/mpi/mpi-add.c89
1 files changed, 26 insertions, 63 deletions
diff --git a/lib/crypto/mpi/mpi-add.c b/lib/crypto/mpi/mpi-add.c
index 9056fc5167fc..3015140d4860 100644
--- a/lib/crypto/mpi/mpi-add.c
+++ b/lib/crypto/mpi/mpi-add.c
@@ -13,62 +13,12 @@
#include "mpi-internal.h"
-/****************
- * Add the unsigned integer V to the mpi-integer U and store the
- * result in W. U and V may be the same.
- */
-void mpi_add_ui(MPI w, MPI u, unsigned long v)
-{
- mpi_ptr_t wp, up;
- mpi_size_t usize, wsize;
- int usign, wsign;
-
- usize = u->nlimbs;
- usign = u->sign;
- wsign = 0;
-
- /* If not space for W (and possible carry), increase space. */
- wsize = usize + 1;
- if (w->alloced < wsize)
- mpi_resize(w, wsize);
-
- /* These must be after realloc (U may be the same as W). */
- up = u->d;
- wp = w->d;
-
- if (!usize) { /* simple */
- wp[0] = v;
- wsize = v ? 1:0;
- } else if (!usign) { /* mpi is not negative */
- mpi_limb_t cy;
- cy = mpihelp_add_1(wp, up, usize, v);
- wp[usize] = cy;
- wsize = usize + cy;
- } else {
- /* The signs are different. Need exact comparison to determine
- * which operand to subtract from which.
- */
- if (usize == 1 && up[0] < v) {
- wp[0] = v - up[0];
- wsize = 1;
- } else {
- mpihelp_sub_1(wp, up, usize, v);
- /* Size can decrease with at most one limb. */
- wsize = usize - (wp[usize-1] == 0);
- wsign = 1;
- }
- }
-
- w->nlimbs = wsize;
- w->sign = wsign;
-}
-
-
-void mpi_add(MPI w, MPI u, MPI v)
+int mpi_add(MPI w, MPI u, MPI v)
{
mpi_ptr_t wp, up, vp;
mpi_size_t usize, vsize, wsize;
int usign, vsign, wsign;
+ int err;
if (u->nlimbs < v->nlimbs) { /* Swap U and V. */
usize = v->nlimbs;
@@ -76,7 +26,9 @@ void mpi_add(MPI w, MPI u, MPI v)
vsize = u->nlimbs;
vsign = u->sign;
wsize = usize + 1;
- RESIZE_IF_NEEDED(w, wsize);
+ err = RESIZE_IF_NEEDED(w, wsize);
+ if (err)
+ return err;
/* These must be after realloc (u or v may be the same as w). */
up = v->d;
vp = u->d;
@@ -86,7 +38,9 @@ void mpi_add(MPI w, MPI u, MPI v)
vsize = v->nlimbs;
vsign = v->sign;
wsize = usize + 1;
- RESIZE_IF_NEEDED(w, wsize);
+ err = RESIZE_IF_NEEDED(w, wsize);
+ if (err)
+ return err;
/* These must be after realloc (u or v may be the same as w). */
up = u->d;
vp = v->d;
@@ -128,28 +82,37 @@ void mpi_add(MPI w, MPI u, MPI v)
w->nlimbs = wsize;
w->sign = wsign;
+ return 0;
}
EXPORT_SYMBOL_GPL(mpi_add);
-void mpi_sub(MPI w, MPI u, MPI v)
+int mpi_sub(MPI w, MPI u, MPI v)
{
- MPI vv = mpi_copy(v);
+ int err;
+ MPI vv;
+
+ vv = mpi_copy(v);
+ if (!vv)
+ return -ENOMEM;
+
vv->sign = !vv->sign;
- mpi_add(w, u, vv);
+ err = mpi_add(w, u, vv);
mpi_free(vv);
+
+ return err;
}
EXPORT_SYMBOL_GPL(mpi_sub);
-void mpi_addm(MPI w, MPI u, MPI v, MPI m)
+int mpi_addm(MPI w, MPI u, MPI v, MPI m)
{
- mpi_add(w, u, v);
- mpi_mod(w, w, m);
+ return mpi_add(w, u, v) ?:
+ mpi_mod(w, w, m);
}
EXPORT_SYMBOL_GPL(mpi_addm);
-void mpi_subm(MPI w, MPI u, MPI v, MPI m)
+int mpi_subm(MPI w, MPI u, MPI v, MPI m)
{
- mpi_sub(w, u, v);
- mpi_mod(w, w, m);
+ return mpi_sub(w, u, v) ?:
+ mpi_mod(w, w, m);
}
EXPORT_SYMBOL_GPL(mpi_subm);