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Diffstat (limited to 'src/crypto/fipsmodule/bn/mul.c')
-rw-r--r--src/crypto/fipsmodule/bn/mul.c212
1 files changed, 104 insertions, 108 deletions
diff --git a/src/crypto/fipsmodule/bn/mul.c b/src/crypto/fipsmodule/bn/mul.c
index 36a40601..7cc0e3cd 100644
--- a/src/crypto/fipsmodule/bn/mul.c
+++ b/src/crypto/fipsmodule/bn/mul.c
@@ -113,15 +113,15 @@ static void bn_mul_normal(BN_ULONG *r, BN_ULONG *a, int na, BN_ULONG *b,
}
#if !defined(OPENSSL_X86) || defined(OPENSSL_NO_ASM)
-/* Here follows specialised variants of bn_add_words() and bn_sub_words(). They
- * have the property performing operations on arrays of different sizes. The
- * sizes of those arrays is expressed through cl, which is the common length (
- * basicall, min(len(a),len(b)) ), and dl, which is the delta between the two
- * lengths, calculated as len(a)-len(b). All lengths are the number of
- * BN_ULONGs... For the operations that require a result array as parameter,
- * it must have the length cl+abs(dl). These functions should probably end up
- * in bn_asm.c as soon as there are assembler counterparts for the systems that
- * use assembler files. */
+// Here follows specialised variants of bn_add_words() and bn_sub_words(). They
+// have the property performing operations on arrays of different sizes. The
+// sizes of those arrays is expressed through cl, which is the common length (
+// basicall, min(len(a),len(b)) ), and dl, which is the delta between the two
+// lengths, calculated as len(a)-len(b). All lengths are the number of
+// BN_ULONGs... For the operations that require a result array as parameter,
+// it must have the length cl+abs(dl). These functions should probably end up
+// in bn_asm.c as soon as there are assembler counterparts for the systems that
+// use assembler files.
static BN_ULONG bn_sub_part_words(BN_ULONG *r, const BN_ULONG *a,
const BN_ULONG *b, int cl, int dl) {
@@ -274,25 +274,24 @@ static BN_ULONG bn_sub_part_words(BN_ULONG *r, const BN_ULONG *a,
return c;
}
#else
-/* On other platforms the function is defined in asm. */
+// On other platforms the function is defined in asm.
BN_ULONG bn_sub_part_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b,
int cl, int dl);
#endif
-/* Karatsuba recursive multiplication algorithm
- * (cf. Knuth, The Art of Computer Programming, Vol. 2) */
-
-/* r is 2*n2 words in size,
- * a and b are both n2 words in size.
- * n2 must be a power of 2.
- * We multiply and return the result.
- * t must be 2*n2 words in size
- * We calculate
- * a[0]*b[0]
- * a[0]*b[0]+a[1]*b[1]+(a[0]-a[1])*(b[1]-b[0])
- * a[1]*b[1]
- */
-/* dnX may not be positive, but n2/2+dnX has to be */
+// Karatsuba recursive multiplication algorithm
+// (cf. Knuth, The Art of Computer Programming, Vol. 2)
+
+// r is 2*n2 words in size,
+// a and b are both n2 words in size.
+// n2 must be a power of 2.
+// We multiply and return the result.
+// t must be 2*n2 words in size
+// We calculate
+// a[0]*b[0]
+// a[0]*b[0]+a[1]*b[1]+(a[0]-a[1])*(b[1]-b[0])
+// a[1]*b[1]
+// dnX may not be positive, but n2/2+dnX has to be
static void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
int dna, int dnb, BN_ULONG *t) {
int n = n2 / 2, c1, c2;
@@ -300,15 +299,14 @@ static void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
unsigned int neg, zero;
BN_ULONG ln, lo, *p;
- /* Only call bn_mul_comba 8 if n2 == 8 and the
- * two arrays are complete [steve]
- */
+ // Only call bn_mul_comba 8 if n2 == 8 and the
+ // two arrays are complete [steve]
if (n2 == 8 && dna == 0 && dnb == 0) {
bn_mul_comba8(r, a, b);
return;
}
- /* Else do normal multiply */
+ // Else do normal multiply
if (n2 < BN_MUL_RECURSIVE_SIZE_NORMAL) {
bn_mul_normal(r, a, n2 + dna, b, n2 + dnb);
if ((dna + dnb) < 0) {
@@ -318,21 +316,21 @@ static void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
return;
}
- /* r=(a[0]-a[1])*(b[1]-b[0]) */
+ // r=(a[0]-a[1])*(b[1]-b[0])
c1 = bn_cmp_part_words(a, &(a[n]), tna, n - tna);
c2 = bn_cmp_part_words(&(b[n]), b, tnb, tnb - n);
zero = neg = 0;
switch (c1 * 3 + c2) {
case -4:
- bn_sub_part_words(t, &(a[n]), a, tna, tna - n); /* - */
- bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb); /* - */
+ bn_sub_part_words(t, &(a[n]), a, tna, tna - n); // -
+ bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb); // -
break;
case -3:
zero = 1;
break;
case -2:
- bn_sub_part_words(t, &(a[n]), a, tna, tna - n); /* - */
- bn_sub_part_words(&(t[n]), &(b[n]), b, tnb, tnb - n); /* + */
+ bn_sub_part_words(t, &(a[n]), a, tna, tna - n); // -
+ bn_sub_part_words(&(t[n]), &(b[n]), b, tnb, tnb - n); // +
neg = 1;
break;
case -1:
@@ -341,8 +339,8 @@ static void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
zero = 1;
break;
case 2:
- bn_sub_part_words(t, a, &(a[n]), tna, n - tna); /* + */
- bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb); /* - */
+ bn_sub_part_words(t, a, &(a[n]), tna, n - tna); // +
+ bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb); // -
neg = 1;
break;
case 3:
@@ -355,7 +353,7 @@ static void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
}
if (n == 4 && dna == 0 && dnb == 0) {
- /* XXX: bn_mul_comba4 could take extra args to do this well */
+ // XXX: bn_mul_comba4 could take extra args to do this well
if (!zero) {
bn_mul_comba4(&(t[n2]), t, &(t[n]));
} else {
@@ -365,7 +363,7 @@ static void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
bn_mul_comba4(r, a, b);
bn_mul_comba4(&(r[n2]), &(a[n]), &(b[n]));
} else if (n == 8 && dna == 0 && dnb == 0) {
- /* XXX: bn_mul_comba8 could take extra args to do this well */
+ // XXX: bn_mul_comba8 could take extra args to do this well
if (!zero) {
bn_mul_comba8(&(t[n2]), t, &(t[n]));
} else {
@@ -385,24 +383,24 @@ static void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
bn_mul_recursive(&(r[n2]), &(a[n]), &(b[n]), n, dna, dnb, p);
}
- /* t[32] holds (a[0]-a[1])*(b[1]-b[0]), c1 is the sign
- * r[10] holds (a[0]*b[0])
- * r[32] holds (b[1]*b[1]) */
+ // t[32] holds (a[0]-a[1])*(b[1]-b[0]), c1 is the sign
+ // r[10] holds (a[0]*b[0])
+ // r[32] holds (b[1]*b[1])
c1 = (int)(bn_add_words(t, r, &(r[n2]), n2));
if (neg) {
- /* if t[32] is negative */
+ // if t[32] is negative
c1 -= (int)(bn_sub_words(&(t[n2]), t, &(t[n2]), n2));
} else {
- /* Might have a carry */
+ // Might have a carry
c1 += (int)(bn_add_words(&(t[n2]), &(t[n2]), t, n2));
}
- /* t[32] holds (a[0]-a[1])*(b[1]-b[0])+(a[0]*b[0])+(a[1]*b[1])
- * r[10] holds (a[0]*b[0])
- * r[32] holds (b[1]*b[1])
- * c1 holds the carry bits */
+ // t[32] holds (a[0]-a[1])*(b[1]-b[0])+(a[0]*b[0])+(a[1]*b[1])
+ // r[10] holds (a[0]*b[0])
+ // r[32] holds (b[1]*b[1])
+ // c1 holds the carry bits
c1 += (int)(bn_add_words(&(r[n]), &(r[n]), &(t[n2]), n2));
if (c1) {
p = &(r[n + n2]);
@@ -410,8 +408,8 @@ static void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
ln = (lo + c1) & BN_MASK2;
*p = ln;
- /* The overflow will stop before we over write
- * words we should not overwrite */
+ // The overflow will stop before we over write
+ // words we should not overwrite
if (ln < (BN_ULONG)c1) {
do {
p++;
@@ -423,9 +421,9 @@ static void bn_mul_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2,
}
}
-/* n+tn is the word length
- * t needs to be n*4 is size, as does r */
-/* tnX may not be negative but less than n */
+// n+tn is the word length
+// t needs to be n*4 is size, as does r
+// tnX may not be negative but less than n
static void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n,
int tna, int tnb, BN_ULONG *t) {
int i, j, n2 = n * 2;
@@ -437,33 +435,33 @@ static void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n,
return;
}
- /* r=(a[0]-a[1])*(b[1]-b[0]) */
+ // r=(a[0]-a[1])*(b[1]-b[0])
c1 = bn_cmp_part_words(a, &(a[n]), tna, n - tna);
c2 = bn_cmp_part_words(&(b[n]), b, tnb, tnb - n);
neg = 0;
switch (c1 * 3 + c2) {
case -4:
- bn_sub_part_words(t, &(a[n]), a, tna, tna - n); /* - */
- bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb); /* - */
+ bn_sub_part_words(t, &(a[n]), a, tna, tna - n); // -
+ bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb); // -
break;
case -3:
- /* break; */
+ // break;
case -2:
- bn_sub_part_words(t, &(a[n]), a, tna, tna - n); /* - */
- bn_sub_part_words(&(t[n]), &(b[n]), b, tnb, tnb - n); /* + */
+ bn_sub_part_words(t, &(a[n]), a, tna, tna - n); // -
+ bn_sub_part_words(&(t[n]), &(b[n]), b, tnb, tnb - n); // +
neg = 1;
break;
case -1:
case 0:
case 1:
- /* break; */
+ // break;
case 2:
- bn_sub_part_words(t, a, &(a[n]), tna, n - tna); /* + */
- bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb); /* - */
+ bn_sub_part_words(t, a, &(a[n]), tna, n - tna); // +
+ bn_sub_part_words(&(t[n]), b, &(b[n]), tnb, n - tnb); // -
neg = 1;
break;
case 3:
- /* break; */
+ // break;
case 4:
bn_sub_part_words(t, a, &(a[n]), tna, n - tna);
bn_sub_part_words(&(t[n]), &(b[n]), b, tnb, tnb - n);
@@ -480,8 +478,8 @@ static void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n,
bn_mul_recursive(&(t[n2]), t, &(t[n]), n, 0, 0, p);
bn_mul_recursive(r, a, b, n, 0, 0, p);
i = n / 2;
- /* If there is only a bottom half to the number,
- * just do it */
+ // If there is only a bottom half to the number,
+ // just do it
if (tna > tnb) {
j = tna - i;
} else {
@@ -492,12 +490,12 @@ static void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n,
bn_mul_recursive(&(r[n2]), &(a[n]), &(b[n]), i, tna - i, tnb - i, p);
OPENSSL_memset(&(r[n2 + i * 2]), 0, sizeof(BN_ULONG) * (n2 - i * 2));
} else if (j > 0) {
- /* eg, n == 16, i == 8 and tn == 11 */
+ // eg, n == 16, i == 8 and tn == 11
bn_mul_part_recursive(&(r[n2]), &(a[n]), &(b[n]), i, tna - i, tnb - i, p);
OPENSSL_memset(&(r[n2 + tna + tnb]), 0,
sizeof(BN_ULONG) * (n2 - tna - tnb));
} else {
- /* (j < 0) eg, n == 16, i == 8 and tn == 5 */
+ // (j < 0) eg, n == 16, i == 8 and tn == 5
OPENSSL_memset(&(r[n2]), 0, sizeof(BN_ULONG) * n2);
if (tna < BN_MUL_RECURSIVE_SIZE_NORMAL &&
tnb < BN_MUL_RECURSIVE_SIZE_NORMAL) {
@@ -505,9 +503,9 @@ static void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n,
} else {
for (;;) {
i /= 2;
- /* these simplified conditions work
- * exclusively because difference
- * between tna and tnb is 1 or 0 */
+ // these simplified conditions work
+ // exclusively because difference
+ // between tna and tnb is 1 or 0
if (i < tna || i < tnb) {
bn_mul_part_recursive(&(r[n2]), &(a[n]), &(b[n]), i, tna - i,
tnb - i, p);
@@ -522,25 +520,24 @@ static void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n,
}
}
- /* t[32] holds (a[0]-a[1])*(b[1]-b[0]), c1 is the sign
- * r[10] holds (a[0]*b[0])
- * r[32] holds (b[1]*b[1])
- */
+ // t[32] holds (a[0]-a[1])*(b[1]-b[0]), c1 is the sign
+ // r[10] holds (a[0]*b[0])
+ // r[32] holds (b[1]*b[1])
c1 = (int)(bn_add_words(t, r, &(r[n2]), n2));
if (neg) {
- /* if t[32] is negative */
+ // if t[32] is negative
c1 -= (int)(bn_sub_words(&(t[n2]), t, &(t[n2]), n2));
} else {
- /* Might have a carry */
+ // Might have a carry
c1 += (int)(bn_add_words(&(t[n2]), &(t[n2]), t, n2));
}
- /* t[32] holds (a[0]-a[1])*(b[1]-b[0])+(a[0]*b[0])+(a[1]*b[1])
- * r[10] holds (a[0]*b[0])
- * r[32] holds (b[1]*b[1])
- * c1 holds the carry bits */
+ // t[32] holds (a[0]-a[1])*(b[1]-b[0])+(a[0]*b[0])+(a[1]*b[1])
+ // r[10] holds (a[0]*b[0])
+ // r[32] holds (b[1]*b[1])
+ // c1 holds the carry bits
c1 += (int)(bn_add_words(&(r[n]), &(r[n]), &(t[n2]), n2));
if (c1) {
p = &(r[n + n2]);
@@ -548,8 +545,8 @@ static void bn_mul_part_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n,
ln = (lo + c1) & BN_MASK2;
*p = ln;
- /* The overflow will stop before we over write
- * words we should not overwrite */
+ // The overflow will stop before we over write
+ // words we should not overwrite
if (ln < (BN_ULONG)c1) {
do {
p++;
@@ -627,7 +624,7 @@ int BN_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) {
}
bn_mul_part_recursive(rr->d, a->d, b->d, j, al - j, bl - j, t->d);
} else {
- /* al <= j || bl <= j */
+ // al <= j || bl <= j
if (!bn_wexpand(t, k * 2)) {
goto err;
}
@@ -659,7 +656,7 @@ err:
return ret;
}
-/* tmp must have 2*n words */
+// tmp must have 2*n words
static void bn_sqr_normal(BN_ULONG *r, const BN_ULONG *a, int n, BN_ULONG *tmp) {
int i, j, max;
const BN_ULONG *ap;
@@ -687,23 +684,22 @@ static void bn_sqr_normal(BN_ULONG *r, const BN_ULONG *a, int n, BN_ULONG *tmp)
bn_add_words(r, r, r, max);
- /* There will not be a carry */
+ // There will not be a carry
bn_sqr_words(tmp, a, n);
bn_add_words(r, r, tmp, max);
}
-/* r is 2*n words in size,
- * a and b are both n words in size. (There's not actually a 'b' here ...)
- * n must be a power of 2.
- * We multiply and return the result.
- * t must be 2*n words in size
- * We calculate
- * a[0]*b[0]
- * a[0]*b[0]+a[1]*b[1]+(a[0]-a[1])*(b[1]-b[0])
- * a[1]*b[1]
- */
+// r is 2*n words in size,
+// a and b are both n words in size. (There's not actually a 'b' here ...)
+// n must be a power of 2.
+// We multiply and return the result.
+// t must be 2*n words in size
+// We calculate
+// a[0]*b[0]
+// a[0]*b[0]+a[1]*b[1]+(a[0]-a[1])*(b[1]-b[0])
+// a[1]*b[1]
static void bn_sqr_recursive(BN_ULONG *r, const BN_ULONG *a, int n2, BN_ULONG *t) {
int n = n2 / 2;
int zero, c1;
@@ -720,7 +716,7 @@ static void bn_sqr_recursive(BN_ULONG *r, const BN_ULONG *a, int n2, BN_ULONG *t
bn_sqr_normal(r, a, n2, t);
return;
}
- /* r=(a[0]-a[1])*(a[1]-a[0]) */
+ // r=(a[0]-a[1])*(a[1]-a[0])
c1 = bn_cmp_words(a, &(a[n]), n);
zero = 0;
if (c1 > 0) {
@@ -731,7 +727,7 @@ static void bn_sqr_recursive(BN_ULONG *r, const BN_ULONG *a, int n2, BN_ULONG *t
zero = 1;
}
- /* The result will always be negative unless it is zero */
+ // The result will always be negative unless it is zero
p = &(t[n2 * 2]);
if (!zero) {
@@ -742,19 +738,19 @@ static void bn_sqr_recursive(BN_ULONG *r, const BN_ULONG *a, int n2, BN_ULONG *t
bn_sqr_recursive(r, a, n, p);
bn_sqr_recursive(&(r[n2]), &(a[n]), n, p);
- /* t[32] holds (a[0]-a[1])*(a[1]-a[0]), it is negative or zero
- * r[10] holds (a[0]*b[0])
- * r[32] holds (b[1]*b[1]) */
+ // t[32] holds (a[0]-a[1])*(a[1]-a[0]), it is negative or zero
+ // r[10] holds (a[0]*b[0])
+ // r[32] holds (b[1]*b[1])
c1 = (int)(bn_add_words(t, r, &(r[n2]), n2));
- /* t[32] is negative */
+ // t[32] is negative
c1 -= (int)(bn_sub_words(&(t[n2]), t, &(t[n2]), n2));
- /* t[32] holds (a[0]-a[1])*(a[1]-a[0])+(a[0]*a[0])+(a[1]*a[1])
- * r[10] holds (a[0]*a[0])
- * r[32] holds (a[1]*a[1])
- * c1 holds the carry bits */
+ // t[32] holds (a[0]-a[1])*(a[1]-a[0])+(a[0]*a[0])+(a[1]*a[1])
+ // r[10] holds (a[0]*a[0])
+ // r[32] holds (a[1]*a[1])
+ // c1 holds the carry bits
c1 += (int)(bn_add_words(&(r[n]), &(r[n]), &(t[n2]), n2));
if (c1) {
p = &(r[n + n2]);
@@ -762,8 +758,8 @@ static void bn_sqr_recursive(BN_ULONG *r, const BN_ULONG *a, int n2, BN_ULONG *t
ln = (lo + c1) & BN_MASK2;
*p = ln;
- /* The overflow will stop before we over write
- * words we should not overwrite */
+ // The overflow will stop before we over write
+ // words we should not overwrite
if (ln < (BN_ULONG)c1) {
do {
p++;
@@ -818,7 +814,7 @@ int BN_sqr(BIGNUM *r, const BIGNUM *a, BN_CTX *ctx) {
goto err;
}
- max = 2 * al; /* Non-zero (from above) */
+ max = 2 * al; // Non-zero (from above)
if (!bn_wexpand(rr, max)) {
goto err;
}
@@ -852,8 +848,8 @@ int BN_sqr(BIGNUM *r, const BIGNUM *a, BN_CTX *ctx) {
}
rr->neg = 0;
- /* If the most-significant half of the top word of 'a' is zero, then
- * the square of 'a' will max-1 words. */
+ // If the most-significant half of the top word of 'a' is zero, then
+ // the square of 'a' will max-1 words.
if (a->d[al - 1] == (a->d[al - 1] & BN_MASK2l)) {
rr->top = max - 1;
} else {
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-25 06:13:53 +0000