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|
--- crypto/openssl/crypto/bn/bn_exp.c.orig
+++ crypto/openssl/crypto/bn/bn_exp.c
@@ -107,13 +107,13 @@
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
- */
-
-#include "cryptlib.h"
-#include "constant_time_locl.h"
-#include "bn_lcl.h"
-
-/* maximum precomputation table size for *variable* sliding windows */
+ */
+
+#include "cryptlib.h"
+#include "constant_time_locl.h"
+#include "bn_lcl.h"
+
+/* maximum precomputation table size for *variable* sliding windows */
#define TABLE_SIZE 32
/* this one works - simple but works */
@@ -521,79 +521,79 @@
* pattern as far as cache lines are concerned. The following functions are
* used to transfer a BIGNUM from/to that table.
*/
-
-static int MOD_EXP_CTIME_COPY_TO_PREBUF(BIGNUM *b, int top,
- unsigned char *buf, int idx,
- int window)
-{
- int i, j;
- int width = 1 << window;
- BN_ULONG *table = (BN_ULONG *)buf;
-
- if (bn_wexpand(b, top) == NULL)
- return 0;
+
+static int MOD_EXP_CTIME_COPY_TO_PREBUF(BIGNUM *b, int top,
+ unsigned char *buf, int idx,
+ int window)
+{
+ int i, j;
+ int width = 1 << window;
+ BN_ULONG *table = (BN_ULONG *)buf;
+
+ if (bn_wexpand(b, top) == NULL)
+ return 0;
while (b->top < top) {
- b->d[b->top++] = 0;
- }
-
- for (i = 0, j = idx; i < top; i++, j += width) {
- table[j] = b->d[i];
- }
-
- bn_correct_top(b);
+ b->d[b->top++] = 0;
+ }
+
+ for (i = 0, j = idx; i < top; i++, j += width) {
+ table[j] = b->d[i];
+ }
+
+ bn_correct_top(b);
return 1;
}
-
-static int MOD_EXP_CTIME_COPY_FROM_PREBUF(BIGNUM *b, int top,
- unsigned char *buf, int idx,
- int window)
-{
- int i, j;
- int width = 1 << window;
- volatile BN_ULONG *table = (volatile BN_ULONG *)buf;
-
- if (bn_wexpand(b, top) == NULL)
- return 0;
-
- if (window <= 3) {
- for (i = 0; i < top; i++, table += width) {
- BN_ULONG acc = 0;
-
- for (j = 0; j < width; j++) {
- acc |= table[j] &
- ((BN_ULONG)0 - (constant_time_eq_int(j,idx)&1));
- }
-
- b->d[i] = acc;
- }
- } else {
- int xstride = 1 << (window - 2);
- BN_ULONG y0, y1, y2, y3;
-
- i = idx >> (window - 2); /* equivalent of idx / xstride */
- idx &= xstride - 1; /* equivalent of idx % xstride */
-
- y0 = (BN_ULONG)0 - (constant_time_eq_int(i,0)&1);
- y1 = (BN_ULONG)0 - (constant_time_eq_int(i,1)&1);
- y2 = (BN_ULONG)0 - (constant_time_eq_int(i,2)&1);
- y3 = (BN_ULONG)0 - (constant_time_eq_int(i,3)&1);
-
- for (i = 0; i < top; i++, table += width) {
- BN_ULONG acc = 0;
-
- for (j = 0; j < xstride; j++) {
- acc |= ( (table[j + 0 * xstride] & y0) |
- (table[j + 1 * xstride] & y1) |
- (table[j + 2 * xstride] & y2) |
- (table[j + 3 * xstride] & y3) )
- & ((BN_ULONG)0 - (constant_time_eq_int(j,idx)&1));
- }
-
- b->d[i] = acc;
- }
- }
-
- b->top = top;
+
+static int MOD_EXP_CTIME_COPY_FROM_PREBUF(BIGNUM *b, int top,
+ unsigned char *buf, int idx,
+ int window)
+{
+ int i, j;
+ int width = 1 << window;
+ volatile BN_ULONG *table = (volatile BN_ULONG *)buf;
+
+ if (bn_wexpand(b, top) == NULL)
+ return 0;
+
+ if (window <= 3) {
+ for (i = 0; i < top; i++, table += width) {
+ BN_ULONG acc = 0;
+
+ for (j = 0; j < width; j++) {
+ acc |= table[j] &
+ ((BN_ULONG)0 - (constant_time_eq_int(j,idx)&1));
+ }
+
+ b->d[i] = acc;
+ }
+ } else {
+ int xstride = 1 << (window - 2);
+ BN_ULONG y0, y1, y2, y3;
+
+ i = idx >> (window - 2); /* equivalent of idx / xstride */
+ idx &= xstride - 1; /* equivalent of idx % xstride */
+
+ y0 = (BN_ULONG)0 - (constant_time_eq_int(i,0)&1);
+ y1 = (BN_ULONG)0 - (constant_time_eq_int(i,1)&1);
+ y2 = (BN_ULONG)0 - (constant_time_eq_int(i,2)&1);
+ y3 = (BN_ULONG)0 - (constant_time_eq_int(i,3)&1);
+
+ for (i = 0; i < top; i++, table += width) {
+ BN_ULONG acc = 0;
+
+ for (j = 0; j < xstride; j++) {
+ acc |= ( (table[j + 0 * xstride] & y0) |
+ (table[j + 1 * xstride] & y1) |
+ (table[j + 2 * xstride] & y2) |
+ (table[j + 3 * xstride] & y3) )
+ & ((BN_ULONG)0 - (constant_time_eq_int(j,idx)&1));
+ }
+
+ b->d[i] = acc;
+ }
+ }
+
+ b->top = top;
bn_correct_top(b);
return 1;
}
@@ -684,13 +684,13 @@
/*
* Initialize the intermediate result. Do this early to save double
* conversion, once each for a^0 and intermediate result.
- */
- if (!BN_to_montgomery(r, BN_value_one(), mont, ctx))
- goto err;
- if (!MOD_EXP_CTIME_COPY_TO_PREBUF(r, top, powerbuf, 0, window))
- goto err;
-
- /* Initialize computeTemp as a^1 with montgomery precalcs */
+ */
+ if (!BN_to_montgomery(r, BN_value_one(), mont, ctx))
+ goto err;
+ if (!MOD_EXP_CTIME_COPY_TO_PREBUF(r, top, powerbuf, 0, window))
+ goto err;
+
+ /* Initialize computeTemp as a^1 with montgomery precalcs */
computeTemp = BN_CTX_get(ctx);
am = BN_CTX_get(ctx);
if (computeTemp == NULL || am == NULL)
@@ -703,13 +703,13 @@
} else
aa = a;
if (!BN_to_montgomery(am, aa, mont, ctx))
- goto err;
- if (!BN_copy(computeTemp, am))
- goto err;
- if (!MOD_EXP_CTIME_COPY_TO_PREBUF(am, top, powerbuf, 1, window))
- goto err;
-
- /*
+ goto err;
+ if (!BN_copy(computeTemp, am))
+ goto err;
+ if (!MOD_EXP_CTIME_COPY_TO_PREBUF(am, top, powerbuf, 1, window))
+ goto err;
+
+ /*
* If the window size is greater than 1, then calculate
* val[i=2..2^winsize-1]. Powers are computed as a*a^(i-1) (even powers
* could instead be computed as (a^(i/2))^2 to use the slight performance
@@ -718,14 +718,14 @@
if (window > 1) {
for (i = 2; i < numPowers; i++) {
/* Calculate a^i = a^(i-1) * a */
- if (!BN_mod_mul_montgomery
- (computeTemp, am, computeTemp, mont, ctx))
- goto err;
- if (!MOD_EXP_CTIME_COPY_TO_PREBUF(computeTemp, top, powerbuf, i,
- window))
- goto err;
- }
- }
+ if (!BN_mod_mul_montgomery
+ (computeTemp, am, computeTemp, mont, ctx))
+ goto err;
+ if (!MOD_EXP_CTIME_COPY_TO_PREBUF(computeTemp, top, powerbuf, i,
+ window))
+ goto err;
+ }
+ }
/*
* Adjust the number of bits up to a multiple of the window size. If the
@@ -758,7 +758,7 @@
* Fetch the appropriate pre-computed value from the pre-buf
*/
if (!MOD_EXP_CTIME_COPY_FROM_PREBUF
- (computeTemp, top, powerbuf, wvalue, numPowers))
+ (computeTemp, top, powerbuf, wvalue, window))
goto err;
/* Multiply the result into the intermediate result */
|
