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Diffstat (limited to 'lib/crypto/mpi/mpi-div.c')
-rw-r--r--lib/crypto/mpi/mpi-div.c82
1 files changed, 39 insertions, 43 deletions
diff --git a/lib/crypto/mpi/mpi-div.c b/lib/crypto/mpi/mpi-div.c
index 45beab8b9e9e..6e5044e72595 100644
--- a/lib/crypto/mpi/mpi-div.c
+++ b/lib/crypto/mpi/mpi-div.c
@@ -14,13 +14,13 @@
#include "mpi-internal.h"
#include "longlong.h"
-void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den);
-void mpi_fdiv_qr(MPI quot, MPI rem, MPI dividend, MPI divisor);
+int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den);
-void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
+int mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
{
int divisor_sign = divisor->sign;
MPI temp_divisor = NULL;
+ int err;
/* We need the original value of the divisor after the remainder has been
* preliminary calculated. We have to copy it to temporary space if it's
@@ -28,44 +28,22 @@ void mpi_fdiv_r(MPI rem, MPI dividend, MPI divisor)
*/
if (rem == divisor) {
temp_divisor = mpi_copy(divisor);
+ if (!temp_divisor)
+ return -ENOMEM;
divisor = temp_divisor;
}
- mpi_tdiv_r(rem, dividend, divisor);
+ err = mpi_tdiv_r(rem, dividend, divisor);
+ if (err)
+ goto free_temp_divisor;
if (((divisor_sign?1:0) ^ (dividend->sign?1:0)) && rem->nlimbs)
- mpi_add(rem, rem, divisor);
+ err = mpi_add(rem, rem, divisor);
- if (temp_divisor)
- mpi_free(temp_divisor);
-}
+free_temp_divisor:
+ mpi_free(temp_divisor);
-void mpi_fdiv_q(MPI quot, MPI dividend, MPI divisor)
-{
- MPI tmp = mpi_alloc(mpi_get_nlimbs(quot));
- mpi_fdiv_qr(quot, tmp, dividend, divisor);
- mpi_free(tmp);
-}
-
-void mpi_fdiv_qr(MPI quot, MPI rem, MPI dividend, MPI divisor)
-{
- int divisor_sign = divisor->sign;
- MPI temp_divisor = NULL;
-
- if (quot == divisor || rem == divisor) {
- temp_divisor = mpi_copy(divisor);
- divisor = temp_divisor;
- }
-
- mpi_tdiv_qr(quot, rem, dividend, divisor);
-
- if ((divisor_sign ^ dividend->sign) && rem->nlimbs) {
- mpi_sub_ui(quot, quot, 1);
- mpi_add(rem, rem, divisor);
- }
-
- if (temp_divisor)
- mpi_free(temp_divisor);
+ return err;
}
/* If den == quot, den needs temporary storage.
@@ -75,12 +53,12 @@ void mpi_fdiv_qr(MPI quot, MPI rem, MPI dividend, MPI divisor)
* i.e no extra storage should be allocated.
*/
-void mpi_tdiv_r(MPI rem, MPI num, MPI den)
+int mpi_tdiv_r(MPI rem, MPI num, MPI den)
{
- mpi_tdiv_qr(NULL, rem, num, den);
+ return mpi_tdiv_qr(NULL, rem, num, den);
}
-void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
+int mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
{
mpi_ptr_t np, dp;
mpi_ptr_t qp, rp;
@@ -93,13 +71,16 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
mpi_limb_t q_limb;
mpi_ptr_t marker[5];
int markidx = 0;
+ int err;
/* Ensure space is enough for quotient and remainder.
* We need space for an extra limb in the remainder, because it's
* up-shifted (normalized) below.
*/
rsize = nsize + 1;
- mpi_resize(rem, rsize);
+ err = mpi_resize(rem, rsize);
+ if (err)
+ return err;
qsize = rsize - dsize; /* qsize cannot be bigger than this. */
if (qsize <= 0) {
@@ -115,11 +96,14 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
quot->nlimbs = 0;
quot->sign = 0;
}
- return;
+ return 0;
}
- if (quot)
- mpi_resize(quot, qsize);
+ if (quot) {
+ err = mpi_resize(quot, qsize);
+ if (err)
+ return err;
+ }
/* Read pointers here, when reallocation is finished. */
np = num->d;
@@ -141,10 +125,10 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
rsize = rlimb != 0?1:0;
rem->nlimbs = rsize;
rem->sign = sign_remainder;
- return;
+ return 0;
}
-
+ err = -ENOMEM;
if (quot) {
qp = quot->d;
/* Make sure QP and NP point to different objects. Otherwise the
@@ -152,6 +136,8 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
*/
if (qp == np) { /* Copy NP object to temporary space. */
np = marker[markidx++] = mpi_alloc_limb_space(nsize);
+ if (!np)
+ goto out_free_marker;
MPN_COPY(np, qp, nsize);
}
} else /* Put quotient at top of remainder. */
@@ -172,6 +158,8 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
* the original contents of the denominator.
*/
tp = marker[markidx++] = mpi_alloc_limb_space(dsize);
+ if (!tp)
+ goto out_free_marker;
mpihelp_lshift(tp, dp, dsize, normalization_steps);
dp = tp;
@@ -193,6 +181,8 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
mpi_ptr_t tp;
tp = marker[markidx++] = mpi_alloc_limb_space(dsize);
+ if (!tp)
+ goto out_free_marker;
MPN_COPY(tp, dp, dsize);
dp = tp;
}
@@ -227,8 +217,14 @@ void mpi_tdiv_qr(MPI quot, MPI rem, MPI num, MPI den)
rem->nlimbs = rsize;
rem->sign = sign_remainder;
+
+ err = 0;
+
+out_free_marker:
while (markidx) {
markidx--;
mpi_free_limb_space(marker[markidx]);
}
+
+ return err;
}