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Diffstat (limited to 'Cryptlib/OpenSSL/crypto/bn/bn_mont.c')
-rw-r--r--Cryptlib/OpenSSL/crypto/bn/bn_mont.c404
1 files changed, 79 insertions, 325 deletions
diff --git a/Cryptlib/OpenSSL/crypto/bn/bn_mont.c b/Cryptlib/OpenSSL/crypto/bn/bn_mont.c
index bf40e823..aadd5db1 100644
--- a/Cryptlib/OpenSSL/crypto/bn/bn_mont.c
+++ b/Cryptlib/OpenSSL/crypto/bn/bn_mont.c
@@ -122,20 +122,7 @@
#define MONT_WORD /* use the faster word-based algorithm */
-#if defined(MONT_WORD) && defined(OPENSSL_BN_ASM_MONT) && (BN_BITS2<=32)
-/*
- * This condition means we have a specific non-default build: In the 0.9.8
- * branch, OPENSSL_BN_ASM_MONT is normally not set for any BN_BITS2<=32
- * platform; an explicit "enable-montasm" is required. I.e., if we are here,
- * the user intentionally deviates from the normal stable build to get better
- * Montgomery performance from the 0.9.9-dev backport. In this case only, we
- * also enable BN_from_montgomery_word() (another non-stable feature from
- * 0.9.9-dev).
- */
-# define MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD
-#endif
-
-#ifdef MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD
+#ifdef MONT_WORD
static int BN_from_montgomery_word(BIGNUM *ret, BIGNUM *r, BN_MONT_CTX *mont);
#endif
@@ -150,12 +137,7 @@ int BN_mod_mul_montgomery(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
if (num > 1 && a->top == num && b->top == num) {
if (bn_wexpand(r, num) == NULL)
return (0);
-# if 0 /* for OpenSSL 0.9.9 mont->n0 */
- if (bn_mul_mont(r->d, a->d, b->d, mont->N.d, mont->n0, num))
-# else
- if (bn_mul_mont(r->d, a->d, b->d, mont->N.d, &mont->n0, num))
-# endif
- {
+ if (bn_mul_mont(r->d, a->d, b->d, mont->N.d, mont->n0, num)) {
r->neg = a->neg ^ b->neg;
r->top = num;
bn_correct_top(r);
@@ -178,7 +160,7 @@ int BN_mod_mul_montgomery(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
goto err;
}
/* reduce from aRR to aR */
-#ifdef MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD
+#ifdef MONT_WORD
if (!BN_from_montgomery_word(r, tmp, mont))
goto err;
#else
@@ -192,49 +174,43 @@ int BN_mod_mul_montgomery(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
return (ret);
}
-#ifdef MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD
+#ifdef MONT_WORD
static int BN_from_montgomery_word(BIGNUM *ret, BIGNUM *r, BN_MONT_CTX *mont)
{
BIGNUM *n;
- BN_ULONG *ap, *np, *rp, n0, v, *nrp;
- int al, nl, max, i, x, ri;
+ BN_ULONG *ap, *np, *rp, n0, v, carry;
+ int nl, max, i;
n = &(mont->N);
- /*
- * mont->ri is the size of mont->N in bits (rounded up to the word size)
- */
- al = ri = mont->ri / BN_BITS2;
-
nl = n->top;
- if ((al == 0) || (nl == 0)) {
+ if (nl == 0) {
ret->top = 0;
return (1);
}
- max = (nl + al + 1); /* allow for overflow (no?) XXX */
+ max = (2 * nl); /* carry is stored separately */
if (bn_wexpand(r, max) == NULL)
return (0);
r->neg ^= n->neg;
np = n->d;
rp = r->d;
- nrp = &(r->d[nl]);
/* clear the top words of T */
+# if 1
for (i = r->top; i < max; i++) /* memset? XXX */
- r->d[i] = 0;
+ rp[i] = 0;
+# else
+ memset(&(rp[r->top]), 0, (max - r->top) * sizeof(BN_ULONG));
+# endif
r->top = max;
-# if 0 /* for OpenSSL 0.9.9 mont->n0 */
n0 = mont->n0[0];
-# else
- n0 = mont->n0;
-# endif
# ifdef BN_COUNT
fprintf(stderr, "word BN_from_montgomery_word %d * %d\n", nl, nl);
# endif
- for (i = 0; i < nl; i++) {
+ for (carry = 0, i = 0; i < nl; i++, rp++) {
# ifdef __TANDEM
{
long long t1;
@@ -251,285 +227,78 @@ static int BN_from_montgomery_word(BIGNUM *ret, BIGNUM *r, BN_MONT_CTX *mont)
# else
v = bn_mul_add_words(rp, np, nl, (rp[0] * n0) & BN_MASK2);
# endif
- nrp++;
- rp++;
- if (((nrp[-1] += v) & BN_MASK2) >= v)
- continue;
- else {
- if (((++nrp[0]) & BN_MASK2) != 0)
- continue;
- if (((++nrp[1]) & BN_MASK2) != 0)
- continue;
- for (x = 2; (((++nrp[x]) & BN_MASK2) == 0); x++) ;
- }
- }
- bn_correct_top(r);
-
- /*
- * mont->ri will be a multiple of the word size and below code is kind of
- * BN_rshift(ret,r,mont->ri) equivalent
- */
- if (r->top <= ri) {
- ret->top = 0;
- return (1);
+ v = (v + carry + rp[nl]) & BN_MASK2;
+ carry |= (v != rp[nl]);
+ carry &= (v <= rp[nl]);
+ rp[nl] = v;
}
- al = r->top - ri;
- if (bn_wexpand(ret, ri) == NULL)
+ if (bn_wexpand(ret, nl) == NULL)
return (0);
- x = 0 - (((al - ri) >> (sizeof(al) * 8 - 1)) & 1);
- ret->top = x = (ri & ~x) | (al & x); /* min(ri,al) */
+ ret->top = nl;
ret->neg = r->neg;
rp = ret->d;
- ap = &(r->d[ri]);
+ ap = &(r->d[nl]);
+# define BRANCH_FREE 1
+# if BRANCH_FREE
{
- size_t m1, m2;
+ BN_ULONG *nrp;
+ size_t m;
- v = bn_sub_words(rp, ap, np, ri);
+ v = bn_sub_words(rp, ap, np, nl) - carry;
/*
- * this ----------------^^ works even in al<ri case thanks to zealous
- * zeroing of top of the vector in the beginning.
+ * if subtraction result is real, then trick unconditional memcpy
+ * below to perform in-place "refresh" instead of actual copy.
*/
-
- /* if (al==ri && !v) || al>ri) nrp=rp; else nrp=ap; */
- /*
- * in other words if subtraction result is real, then trick
- * unconditional memcpy below to perform in-place "refresh" instead
- * of actual copy.
- */
- m1 = 0 - (size_t)(((al - ri) >> (sizeof(al) * 8 - 1)) & 1); /* al<ri */
- m2 = 0 - (size_t)(((ri - al) >> (sizeof(al) * 8 - 1)) & 1); /* al>ri */
- m1 |= m2; /* (al!=ri) */
- m1 |= (0 - (size_t)v); /* (al!=ri || v) */
- m1 &= ~m2; /* (al!=ri || v) && !al>ri */
- nrp = (BN_ULONG *)(((size_t)rp & ~m1) | ((size_t)ap & m1));
- }
-
- /*
- * 'i<ri' is chosen to eliminate dependency on input data, even though it
- * results in redundant copy in al<ri case.
- */
- for (i = 0, ri -= 4; i < ri; i += 4) {
- BN_ULONG t1, t2, t3, t4;
-
- t1 = nrp[i + 0];
- t2 = nrp[i + 1];
- t3 = nrp[i + 2];
- ap[i + 0] = 0;
- t4 = nrp[i + 3];
- ap[i + 1] = 0;
- rp[i + 0] = t1;
- ap[i + 2] = 0;
- rp[i + 1] = t2;
- ap[i + 3] = 0;
- rp[i + 2] = t3;
- rp[i + 3] = t4;
+ m = (0 - (size_t)v);
+ nrp =
+ (BN_ULONG *)(((PTR_SIZE_INT) rp & ~m) | ((PTR_SIZE_INT) ap & m));
+
+ for (i = 0, nl -= 4; i < nl; i += 4) {
+ BN_ULONG t1, t2, t3, t4;
+
+ t1 = nrp[i + 0];
+ t2 = nrp[i + 1];
+ t3 = nrp[i + 2];
+ ap[i + 0] = 0;
+ t4 = nrp[i + 3];
+ ap[i + 1] = 0;
+ rp[i + 0] = t1;
+ ap[i + 2] = 0;
+ rp[i + 1] = t2;
+ ap[i + 3] = 0;
+ rp[i + 2] = t3;
+ rp[i + 3] = t4;
+ }
+ for (nl += 4; i < nl; i++)
+ rp[i] = nrp[i], ap[i] = 0;
}
- for (ri += 4; i < ri; i++)
- rp[i] = nrp[i], ap[i] = 0;
+# else
+ if (bn_sub_words(rp, ap, np, nl) - carry)
+ memcpy(rp, ap, nl * sizeof(BN_ULONG));
+# endif
bn_correct_top(r);
bn_correct_top(ret);
bn_check_top(ret);
return (1);
}
+#endif /* MONT_WORD */
int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, BN_MONT_CTX *mont,
BN_CTX *ctx)
{
int retn = 0;
+#ifdef MONT_WORD
BIGNUM *t;
BN_CTX_start(ctx);
if ((t = BN_CTX_get(ctx)) && BN_copy(t, a))
retn = BN_from_montgomery_word(ret, t, mont);
BN_CTX_end(ctx);
- return retn;
-}
-
-#else /* !MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD */
-
-int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, BN_MONT_CTX *mont,
- BN_CTX *ctx)
-{
- int retn = 0;
-
-# ifdef MONT_WORD
- BIGNUM *n, *r;
- BN_ULONG *ap, *np, *rp, n0, v, *nrp;
- int al, nl, max, i, x, ri;
-
- BN_CTX_start(ctx);
- if ((r = BN_CTX_get(ctx)) == NULL)
- goto err;
-
- if (!BN_copy(r, a))
- goto err;
- n = &(mont->N);
-
- ap = a->d;
- /*
- * mont->ri is the size of mont->N in bits (rounded up to the word size)
- */
- al = ri = mont->ri / BN_BITS2;
-
- nl = n->top;
- if ((al == 0) || (nl == 0)) {
- r->top = 0;
- return (1);
- }
-
- max = (nl + al + 1); /* allow for overflow (no?) XXX */
- if (bn_wexpand(r, max) == NULL)
- goto err;
-
- r->neg = a->neg ^ n->neg;
- np = n->d;
- rp = r->d;
- nrp = &(r->d[nl]);
-
- /* clear the top words of T */
-# if 1
- for (i = r->top; i < max; i++) /* memset? XXX */
- r->d[i] = 0;
-# else
- memset(&(r->d[r->top]), 0, (max - r->top) * sizeof(BN_ULONG));
-# endif
-
- r->top = max;
- n0 = mont->n0;
-
-# ifdef BN_COUNT
- fprintf(stderr, "word BN_from_montgomery %d * %d\n", nl, nl);
-# endif
- for (i = 0; i < nl; i++) {
-# ifdef __TANDEM
- {
- long long t1;
- long long t2;
- long long t3;
- t1 = rp[0] * (n0 & 0177777);
- t2 = 037777600000l;
- t2 = n0 & t2;
- t3 = rp[0] & 0177777;
- t2 = (t3 * t2) & BN_MASK2;
- t1 = t1 + t2;
- v = bn_mul_add_words(rp, np, nl, (BN_ULONG)t1);
- }
-# else
- v = bn_mul_add_words(rp, np, nl, (rp[0] * n0) & BN_MASK2);
-# endif
- nrp++;
- rp++;
- if (((nrp[-1] += v) & BN_MASK2) >= v)
- continue;
- else {
- if (((++nrp[0]) & BN_MASK2) != 0)
- continue;
- if (((++nrp[1]) & BN_MASK2) != 0)
- continue;
- for (x = 2; (((++nrp[x]) & BN_MASK2) == 0); x++) ;
- }
- }
- bn_correct_top(r);
-
- /*
- * mont->ri will be a multiple of the word size and below code is kind of
- * BN_rshift(ret,r,mont->ri) equivalent
- */
- if (r->top <= ri) {
- ret->top = 0;
- retn = 1;
- goto err;
- }
- al = r->top - ri;
-
-# define BRANCH_FREE 1
-# if BRANCH_FREE
- if (bn_wexpand(ret, ri) == NULL)
- goto err;
- x = 0 - (((al - ri) >> (sizeof(al) * 8 - 1)) & 1);
- ret->top = x = (ri & ~x) | (al & x); /* min(ri,al) */
- ret->neg = r->neg;
-
- rp = ret->d;
- ap = &(r->d[ri]);
-
- {
- size_t m1, m2;
-
- v = bn_sub_words(rp, ap, np, ri);
- /*
- * this ----------------^^ works even in al<ri case thanks to zealous
- * zeroing of top of the vector in the beginning.
- */
-
- /* if (al==ri && !v) || al>ri) nrp=rp; else nrp=ap; */
- /*
- * in other words if subtraction result is real, then trick
- * unconditional memcpy below to perform in-place "refresh" instead
- * of actual copy.
- */
- m1 = 0 - (size_t)(((al - ri) >> (sizeof(al) * 8 - 1)) & 1); /* al<ri */
- m2 = 0 - (size_t)(((ri - al) >> (sizeof(al) * 8 - 1)) & 1); /* al>ri */
- m1 |= m2; /* (al!=ri) */
- m1 |= (0 - (size_t)v); /* (al!=ri || v) */
- m1 &= ~m2; /* (al!=ri || v) && !al>ri */
- nrp = (BN_ULONG *)(((size_t)rp & ~m1) | ((size_t)ap & m1));
- }
-
- /*
- * 'i<ri' is chosen to eliminate dependency on input data, even though it
- * results in redundant copy in al<ri case.
- */
- for (i = 0, ri -= 4; i < ri; i += 4) {
- BN_ULONG t1, t2, t3, t4;
-
- t1 = nrp[i + 0];
- t2 = nrp[i + 1];
- t3 = nrp[i + 2];
- ap[i + 0] = 0;
- t4 = nrp[i + 3];
- ap[i + 1] = 0;
- rp[i + 0] = t1;
- ap[i + 2] = 0;
- rp[i + 1] = t2;
- ap[i + 3] = 0;
- rp[i + 2] = t3;
- rp[i + 3] = t4;
- }
- for (ri += 4; i < ri; i++)
- rp[i] = nrp[i], ap[i] = 0;
- bn_correct_top(r);
- bn_correct_top(ret);
-# else
- if (bn_wexpand(ret, al) == NULL)
- goto err;
- ret->top = al;
- ret->neg = r->neg;
-
- rp = ret->d;
- ap = &(r->d[ri]);
- al -= 4;
- for (i = 0; i < al; i += 4) {
- BN_ULONG t1, t2, t3, t4;
-
- t1 = ap[i + 0];
- t2 = ap[i + 1];
- t3 = ap[i + 2];
- t4 = ap[i + 3];
- rp[i + 0] = t1;
- rp[i + 1] = t2;
- rp[i + 2] = t3;
- rp[i + 3] = t4;
- }
- al += 4;
- for (; i < al; i++)
- rp[i] = ap[i];
-# endif
-# else /* !MONT_WORD */
+#else /* !MONT_WORD */
BIGNUM *t1, *t2;
BN_CTX_start(ctx);
@@ -552,21 +321,18 @@ int BN_from_montgomery(BIGNUM *ret, const BIGNUM *a, BN_MONT_CTX *mont,
goto err;
if (!BN_rshift(ret, t2, mont->ri))
goto err;
-# endif /* MONT_WORD */
-# if !defined(BRANCH_FREE) || BRANCH_FREE==0
if (BN_ucmp(ret, &(mont->N)) >= 0) {
if (!BN_usub(ret, ret, &(mont->N)))
goto err;
}
-# endif
retn = 1;
bn_check_top(ret);
err:
BN_CTX_end(ctx);
+#endif /* MONT_WORD */
return (retn);
}
-#endif /* MONT_FROM_WORD___NON_DEFAULT_0_9_8_BUILD */
BN_MONT_CTX *BN_MONT_CTX_new(void)
{
@@ -586,11 +352,7 @@ void BN_MONT_CTX_init(BN_MONT_CTX *ctx)
BN_init(&(ctx->RR));
BN_init(&(ctx->N));
BN_init(&(ctx->Ni));
-#if 0 /* for OpenSSL 0.9.9 mont->n0 */
ctx->n0[0] = ctx->n0[1] = 0;
-#else
- ctx->n0 = 0;
-#endif
ctx->flags = 0;
}
@@ -624,32 +386,25 @@ int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, BN_CTX *ctx)
BIGNUM tmod;
BN_ULONG buf[2];
- mont->ri = (BN_num_bits(mod) + (BN_BITS2 - 1)) / BN_BITS2 * BN_BITS2;
- BN_zero(R);
-# if 0 /* for OpenSSL 0.9.9 mont->n0, would be "#if
- * defined(OPENSSL_BN_ASM_MONT) &&
- * (BN_BITS2<=32)", only certain BN_BITS2<=32
- * platforms actually need this */
- if (!(BN_set_bit(R, 2 * BN_BITS2)))
- goto err; /* R */
-# else
- if (!(BN_set_bit(R, BN_BITS2)))
- goto err; /* R */
-# endif
-
- buf[0] = mod->d[0]; /* tmod = N mod word size */
- buf[1] = 0;
-
BN_init(&tmod);
tmod.d = buf;
- tmod.top = buf[0] != 0 ? 1 : 0;
tmod.dmax = 2;
tmod.neg = 0;
-# if 0 /* for OpenSSL 0.9.9 mont->n0, would be "#if
- * defined(OPENSSL_BN_ASM_MONT) &&
- * (BN_BITS2<=32)"; only certain BN_BITS2<=32
- * platforms actually need this */
+ mont->ri = (BN_num_bits(mod) + (BN_BITS2 - 1)) / BN_BITS2 * BN_BITS2;
+
+# if defined(OPENSSL_BN_ASM_MONT) && (BN_BITS2<=32)
+ /*
+ * Only certain BN_BITS2<=32 platforms actually make use of n0[1],
+ * and we could use the #else case (with a shorter R value) for the
+ * others. However, currently only the assembler files do know which
+ * is which.
+ */
+
+ BN_zero(R);
+ if (!(BN_set_bit(R, 2 * BN_BITS2)))
+ goto err;
+
tmod.top = 0;
if ((buf[0] = mod->d[0]))
tmod.top = 1;
@@ -681,6 +436,13 @@ int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, BN_CTX *ctx)
mont->n0[0] = (Ri->top > 0) ? Ri->d[0] : 0;
mont->n0[1] = (Ri->top > 1) ? Ri->d[1] : 0;
# else
+ BN_zero(R);
+ if (!(BN_set_bit(R, BN_BITS2)))
+ goto err; /* R */
+
+ buf[0] = mod->d[0]; /* tmod = N mod word size */
+ buf[1] = 0;
+ tmod.top = buf[0] != 0 ? 1 : 0;
/* Ri = R^-1 mod N */
if ((BN_mod_inverse(Ri, R, &tmod, ctx)) == NULL)
goto err;
@@ -699,12 +461,8 @@ int BN_MONT_CTX_set(BN_MONT_CTX *mont, const BIGNUM *mod, BN_CTX *ctx)
/*
* Ni = (R*Ri-1)/N, keep only least significant word:
*/
-# if 0 /* for OpenSSL 0.9.9 mont->n0 */
mont->n0[0] = (Ri->top > 0) ? Ri->d[0] : 0;
mont->n0[1] = 0;
-# else
- mont->n0 = (Ri->top > 0) ? Ri->d[0] : 0;
-# endif
# endif
}
#else /* !MONT_WORD */
@@ -753,12 +511,8 @@ BN_MONT_CTX *BN_MONT_CTX_copy(BN_MONT_CTX *to, BN_MONT_CTX *from)
if (!BN_copy(&(to->Ni), &(from->Ni)))
return NULL;
to->ri = from->ri;
-#if 0 /* for OpenSSL 0.9.9 mont->n0 */
to->n0[0] = from->n0[0];
to->n0[1] = from->n0[1];
-#else
- to->n0 = from->n0;
-#endif
return (to);
}
generated by cgit v1.2.3 (git 2.39.1) at 2025-12-17 04:33:48 +0000