* [including the GNU Public Licence.]
*/
+#ifndef BN_DEBUG
+# undef NDEBUG /* avoid conflicting definitions */
+# define NDEBUG
+#endif
+
+#include <assert.h>
+#include <limits.h>
#include <stdio.h>
#include "cryptlib.h"
#include "bn_lcl.h"
* 7 - 128 == 4096
* 8 - 256 == 8192
*/
-OPENSSL_GLOBAL int bn_limit_bits=0;
-OPENSSL_GLOBAL int bn_limit_num=8; /* (1<<bn_limit_bits) */
-OPENSSL_GLOBAL int bn_limit_bits_low=0;
-OPENSSL_GLOBAL int bn_limit_num_low=8; /* (1<<bn_limit_bits_low) */
-OPENSSL_GLOBAL int bn_limit_bits_high=0;
-OPENSSL_GLOBAL int bn_limit_num_high=8; /* (1<<bn_limit_bits_high) */
-OPENSSL_GLOBAL int bn_limit_bits_mont=0;
-OPENSSL_GLOBAL int bn_limit_num_mont=8; /* (1<<bn_limit_bits_mont) */
+static int bn_limit_bits=0;
+static int bn_limit_num=8; /* (1<<bn_limit_bits) */
+static int bn_limit_bits_low=0;
+static int bn_limit_num_low=8; /* (1<<bn_limit_bits_low) */
+static int bn_limit_bits_high=0;
+static int bn_limit_num_high=8; /* (1<<bn_limit_bits_high) */
+static int bn_limit_bits_mont=0;
+static int bn_limit_num_mont=8; /* (1<<bn_limit_bits_mont) */
void BN_set_params(int mult, int high, int low, int mont)
{
if (mult >= 0)
{
- if (mult > (sizeof(int)*8)-1)
+ if (mult > (int)(sizeof(int)*8)-1)
mult=sizeof(int)*8-1;
bn_limit_bits=mult;
bn_limit_num=1<<mult;
}
if (high >= 0)
{
- if (high > (sizeof(int)*8)-1)
+ if (high > (int)(sizeof(int)*8)-1)
high=sizeof(int)*8-1;
bn_limit_bits_high=high;
bn_limit_num_high=1<<high;
}
if (low >= 0)
{
- if (low > (sizeof(int)*8)-1)
+ if (low > (int)(sizeof(int)*8)-1)
low=sizeof(int)*8-1;
bn_limit_bits_low=low;
bn_limit_num_low=1<<low;
}
if (mont >= 0)
{
- if (mont > (sizeof(int)*8)-1)
+ if (mont > (int)(sizeof(int)*8)-1)
mont=sizeof(int)*8-1;
bn_limit_bits_mont=mont;
bn_limit_num_mont=1<<mont;
else return(0);
}
-BIGNUM *BN_value_one(void)
+const BIGNUM *BN_value_one(void)
{
static BN_ULONG data_one=1L;
static BIGNUM const_one={&data_one,1,1,0};
if (a->top == 0) return(0);
l=a->d[a->top-1];
+ assert(l != 0);
i=(a->top-1)*BN_BITS2;
- if (l == 0)
- {
-#if !defined(NO_STDIO) && !defined(WIN16)
- fprintf(stderr,"BAD TOP VALUE\n");
-#endif
- abort();
- }
return(i+BN_num_bits_word(l));
}
if (a == NULL) return;
if (a->d != NULL)
{
- memset(a->d,0,a->max*sizeof(a->d[0]));
+ OPENSSL_cleanse(a->d,a->dmax*sizeof(a->d[0]));
if (!(BN_get_flags(a,BN_FLG_STATIC_DATA)))
- Free(a->d);
+ OPENSSL_free(a->d);
}
i=BN_get_flags(a,BN_FLG_MALLOCED);
- memset(a,0,sizeof(BIGNUM));
+ OPENSSL_cleanse(a,sizeof(BIGNUM));
if (i)
- Free(a);
+ OPENSSL_free(a);
}
void BN_free(BIGNUM *a)
{
if (a == NULL) return;
if ((a->d != NULL) && !(BN_get_flags(a,BN_FLG_STATIC_DATA)))
- Free(a->d);
+ OPENSSL_free(a->d);
a->flags|=BN_FLG_FREE; /* REMOVE? */
if (a->flags & BN_FLG_MALLOCED)
- Free(a);
+ OPENSSL_free(a);
}
void BN_init(BIGNUM *a)
{
memset(a,0,sizeof(BIGNUM));
+ bn_check_top(a);
}
BIGNUM *BN_new(void)
{
BIGNUM *ret;
- if ((ret=(BIGNUM *)Malloc(sizeof(BIGNUM))) == NULL)
+ if ((ret=(BIGNUM *)OPENSSL_malloc(sizeof(BIGNUM))) == NULL)
{
BNerr(BN_F_BN_NEW,ERR_R_MALLOC_FAILURE);
return(NULL);
ret->flags=BN_FLG_MALLOCED;
ret->top=0;
ret->neg=0;
- ret->max=0;
+ ret->dmax=0;
ret->d=NULL;
+ bn_check_top(ret);
return(ret);
}
-
-BN_CTX *BN_CTX_new(void)
+/* This is used both by bn_expand2() and bn_dup_expand() */
+/* The caller MUST check that words > b->dmax before calling this */
+static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words)
{
- BN_CTX *ret;
+ BN_ULONG *A,*a = NULL;
+ const BN_ULONG *B;
+ int i;
- ret=(BN_CTX *)Malloc(sizeof(BN_CTX));
- if (ret == NULL)
+ if (words > (INT_MAX/(4*BN_BITS2)))
{
- BNerr(BN_F_BN_CTX_NEW,ERR_R_MALLOC_FAILURE);
+ BNerr(BN_F_BN_EXPAND_INTERNAL,BN_R_BIGNUM_TOO_LONG);
+ return NULL;
+ }
+
+ bn_check_top(b);
+ if (BN_get_flags(b,BN_FLG_STATIC_DATA))
+ {
+ BNerr(BN_F_BN_EXPAND_INTERNAL,BN_R_EXPAND_ON_STATIC_BIGNUM_DATA);
return(NULL);
}
+ a=A=(BN_ULONG *)OPENSSL_malloc(sizeof(BN_ULONG)*(words+1));
+ if (A == NULL)
+ {
+ BNerr(BN_F_BN_EXPAND_INTERNAL,ERR_R_MALLOC_FAILURE);
+ return(NULL);
+ }
+#if 1
+ B=b->d;
+ /* Check if the previous number needs to be copied */
+ if (B != NULL)
+ {
+ for (i=b->top>>2; i>0; i--,A+=4,B+=4)
+ {
+ /*
+ * The fact that the loop is unrolled
+ * 4-wise is a tribute to Intel. It's
+ * the one that doesn't have enough
+ * registers to accomodate more data.
+ * I'd unroll it 8-wise otherwise:-)
+ *
+ * <appro@fy.chalmers.se>
+ */
+ BN_ULONG a0,a1,a2,a3;
+ a0=B[0]; a1=B[1]; a2=B[2]; a3=B[3];
+ A[0]=a0; A[1]=a1; A[2]=a2; A[3]=a3;
+ }
+ switch (b->top&3)
+ {
+ case 3: A[2]=B[2];
+ case 2: A[1]=B[1];
+ case 1: A[0]=B[0];
+ case 0: /* workaround for ultrix cc: without 'case 0', the optimizer does
+ * the switch table by doing a=top&3; a--; goto jump_table[a];
+ * which fails for top== 0 */
+ ;
+ }
+ }
- BN_CTX_init(ret);
- ret->flags=BN_FLG_MALLOCED;
- return(ret);
+#else
+ memset(A,0,sizeof(BN_ULONG)*(words+1));
+ memcpy(A,b->d,sizeof(b->d[0])*b->top);
+#endif
+
+ return(a);
}
-void BN_CTX_init(BN_CTX *ctx)
- {
- memset(ctx,0,sizeof(BN_CTX));
- ctx->tos=0;
- ctx->flags=0;
- }
+/* This is an internal function that can be used instead of bn_expand2()
+ * when there is a need to copy BIGNUMs instead of only expanding the
+ * data part, while still expanding them.
+ * Especially useful when needing to expand BIGNUMs that are declared
+ * 'const' and should therefore not be changed.
+ * The reason to use this instead of a BN_dup() followed by a bn_expand2()
+ * is memory allocation overhead. A BN_dup() followed by a bn_expand2()
+ * will allocate new memory for the BIGNUM data twice, and free it once,
+ * while bn_dup_expand() makes sure allocation is made only once.
+ */
-void BN_CTX_free(BN_CTX *c)
+BIGNUM *bn_dup_expand(const BIGNUM *b, int words)
{
- int i;
+ BIGNUM *r = NULL;
+
+ /* This function does not work if
+ * words <= b->dmax && top < words
+ * because BN_dup() does not preserve 'dmax'!
+ * (But bn_dup_expand() is not used anywhere yet.)
+ */
+
+ if (words > b->dmax)
+ {
+ BN_ULONG *a = bn_expand_internal(b, words);
- if(c == NULL)
- return;
+ if (a)
+ {
+ r = BN_new();
+ if (r)
+ {
+ r->top = b->top;
+ r->dmax = words;
+ r->neg = b->neg;
+ r->d = a;
+ }
+ else
+ {
+ /* r == NULL, BN_new failure */
+ OPENSSL_free(a);
+ }
+ }
+ /* If a == NULL, there was an error in allocation in
+ bn_expand_internal(), and NULL should be returned */
+ }
+ else
+ {
+ r = BN_dup(b);
+ }
- for (i=0; i<BN_CTX_NUM; i++)
- BN_clear_free(&(c->bn[i]));
- if (c->flags & BN_FLG_MALLOCED)
- Free(c);
+ bn_check_top(r);
+ return r;
}
/* This is an internal function that should not be used in applications.
- * It ensures that 'b' has enough room for a 'bits' bit number. It is
- * mostly used by the various BIGNUM routines. If there is an error,
- * NULL is returned. if not, 'b' is returned.
- */
+ * It ensures that 'b' has enough room for a 'words' word number
+ * and initialises any unused part of b->d with leading zeros.
+ * It is mostly used by the various BIGNUM routines. If there is an error,
+ * NULL is returned. If not, 'b' is returned. */
+
BIGNUM *bn_expand2(BIGNUM *b, int words)
{
- BN_ULONG *A,*a;
- const BN_ULONG *B;
+ BN_ULONG *A;
int i;
- bn_check_top(b);
-
- if (words > b->max)
+ if (words > b->dmax)
{
- bn_check_top(b);
- if (BN_get_flags(b,BN_FLG_STATIC_DATA))
- {
- BNerr(BN_F_BN_EXPAND2,BN_R_EXPAND_ON_STATIC_BIGNUM_DATA);
- return(NULL);
- }
- a=A=(BN_ULONG *)Malloc(sizeof(BN_ULONG)*(words+1));
- if (A == NULL)
- {
- BNerr(BN_F_BN_EXPAND2,ERR_R_MALLOC_FAILURE);
- return(NULL);
- }
-#if 1
- B=b->d;
- /* Check if the previous number needs to be copied */
- if (B != NULL)
+ BN_ULONG *a = bn_expand_internal(b, words);
+
+ if (a)
{
-#if 0
- /* This lot is an unrolled loop to copy b->top
- * BN_ULONGs from B to A
- */
-/*
- * I have nothing against unrolling but it's usually done for
- * several reasons, namely:
- * - minimize percentage of decision making code, i.e. branches;
- * - avoid cache trashing;
- * - make it possible to schedule loads earlier;
- * Now let's examine the code below. The cornerstone of C is
- * "programmer is always right" and that's what we love it for:-)
- * For this very reason C compilers have to be paranoid when it
- * comes to data aliasing and assume the worst. Yeah, but what
- * does it mean in real life? This means that loop body below will
- * be compiled to sequence of loads immediately followed by stores
- * as compiler assumes the worst, something in A==B+1 style. As a
- * result CPU pipeline is going to starve for incoming data. Secondly
- * if A and B happen to share same cache line such code is going to
- * cause severe cache trashing. Both factors have severe impact on
- * performance of modern CPUs and this is the reason why this
- * particular piece of code is #ifdefed away and replaced by more
- * "friendly" version found in #else section below. This comment
- * also applies to BN_copy function.
- *
- * <appro@fy.chalmers.se>
- */
- for (i=b->top&(~7); i>0; i-=8)
- {
- A[0]=B[0]; A[1]=B[1]; A[2]=B[2]; A[3]=B[3];
- A[4]=B[4]; A[5]=B[5]; A[6]=B[6]; A[7]=B[7];
- A+=8;
- B+=8;
- }
- switch (b->top&7)
- {
- case 7:
- A[6]=B[6];
- case 6:
- A[5]=B[5];
- case 5:
- A[4]=B[4];
- case 4:
- A[3]=B[3];
- case 3:
- A[2]=B[2];
- case 2:
- A[1]=B[1];
- case 1:
- A[0]=B[0];
- case 0:
- /* I need the 'case 0' entry for utrix cc.
- * If the optimizer is turned on, it does the
- * switch table by doing
- * a=top&7
- * a--;
- * goto jump_table[a];
- * If top is 0, this makes us jump to 0xffffffc
- * which is rather bad :-(.
- * eric 23-Apr-1998
- */
- ;
- }
-#else
- for (i=b->top>>2; i>0; i--,A+=4,B+=4)
- {
- /*
- * The fact that the loop is unrolled
- * 4-wise is a tribute to Intel. It's
- * the one that doesn't have enough
- * registers to accomodate more data.
- * I'd unroll it 8-wise otherwise:-)
- *
- * <appro@fy.chalmers.se>
- */
- BN_ULONG a0,a1,a2,a3;
- a0=B[0]; a1=B[1]; a2=B[2]; a3=B[3];
- A[0]=a0; A[1]=a1; A[2]=a2; A[3]=a3;
- }
- switch (b->top&3)
- {
- case 3: A[2]=B[2];
- case 2: A[1]=B[1];
- case 1: A[0]=B[0];
- case 0: ; /* ultrix cc workaround, see above */
- }
-#endif
- Free(b->d);
+ if (b->d)
+ OPENSSL_free(b->d);
+ b->d=a;
+ b->dmax=words;
}
-
- b->d=a;
- b->max=words;
-
- /* Now need to zero any data between b->top and b->max */
-
- A= &(b->d[b->top]);
- for (i=(b->max - b->top)>>3; i>0; i--,A+=8)
+ else
+ b = NULL;
+ }
+
+ /* NB: bn_wexpand() calls this only if the BIGNUM really has to grow */
+ if ((b != NULL) && (b->top < b->dmax))
+ {
+ A = &(b->d[b->top]);
+ for (i=(b->dmax - b->top)>>3; i>0; i--,A+=8)
{
A[0]=0; A[1]=0; A[2]=0; A[3]=0;
A[4]=0; A[5]=0; A[6]=0; A[7]=0;
}
- for (i=(b->max - b->top)&7; i>0; i--,A++)
+ for (i=(b->dmax - b->top)&7; i>0; i--,A++)
A[0]=0;
-#else
- memset(A,0,sizeof(BN_ULONG)*(words+1));
- memcpy(A,b->d,sizeof(b->d[0])*b->top);
- b->d=a;
- b->max=words;
-#endif
-
-/* memset(&(p[b->max]),0,((words+1)-b->max)*sizeof(BN_ULONG)); */
-/* { int i; for (i=b->max; i<words+1; i++) p[i]=i;} */
-
+ assert(A == &(b->d[b->dmax]));
}
- return(b);
+ else if(b) bn_check_top(b);
+ return b;
}
BIGNUM *BN_dup(const BIGNUM *a)
{
- BIGNUM *r;
+ BIGNUM *r, *t;
if (a == NULL) return NULL;
bn_check_top(a);
- r=BN_new();
- if (r == NULL) return(NULL);
- return((BIGNUM *)BN_copy(r,a));
+ t = BN_new();
+ if (t == NULL) return(NULL);
+ r = BN_copy(t, a);
+ /* now r == t || r == NULL */
+ if (r == NULL)
+ BN_free(t);
+ bn_check_top(r);
+ return r;
}
BIGNUM *BN_copy(BIGNUM *a, const BIGNUM *b)
case 3: A[2]=B[2];
case 2: A[1]=B[1];
case 1: A[0]=B[0];
- case 0: ; /* ultrix cc workaround, see comments in bn_expand2 */
+ case 0: ; /* ultrix cc workaround, see comments in bn_expand_internal */
}
#else
memcpy(a->d,b->d,sizeof(b->d[0])*b->top);
if ((a->top == 0) && (a->d != NULL))
a->d[0]=0;
a->neg=b->neg;
+ bn_check_top(a);
return(a);
}
+BIGNUM *BN_ncopy(BIGNUM *a, const BIGNUM *b, size_t n)
+ {
+ int i, min;
+ BN_ULONG *A;
+ const BN_ULONG *B;
+
+ bn_check_top(b);
+
+ if (a == b)
+ return a;
+
+ min = (b->top < (int)n)? b->top: (int)n;
+
+ if (!min)
+ {
+ BN_zero(a);
+ return a;
+ }
+
+ if (bn_wexpand(a, min) == NULL)
+ return NULL;
+
+ A=a->d;
+ B=b->d;
+ for (i=min>>2; i>0; i--, A+=4, B+=4)
+ {
+ BN_ULONG a0,a1,a2,a3;
+ a0=B[0]; a1=B[1]; a2=B[2]; a3=B[3];
+ A[0]=a0; A[1]=a1; A[2]=a2; A[3]=a3;
+ }
+ switch (min&3)
+ {
+ case 3: A[2]=B[2];
+ case 2: A[1]=B[1];
+ case 1: A[0]=B[0];
+ case 0: ;
+ }
+ a->top = min;
+
+ a->neg = b->neg;
+ bn_correct_top(a);
+
+ bn_check_top(a);
+ return(a);
+ }
+
+void BN_swap(BIGNUM *a, BIGNUM *b)
+ {
+ int flags_old_a, flags_old_b;
+ BN_ULONG *tmp_d;
+ int tmp_top, tmp_dmax, tmp_neg;
+
+ flags_old_a = a->flags;
+ flags_old_b = b->flags;
+
+ tmp_d = a->d;
+ tmp_top = a->top;
+ tmp_dmax = a->dmax;
+ tmp_neg = a->neg;
+
+ a->d = b->d;
+ a->top = b->top;
+ a->dmax = b->dmax;
+ a->neg = b->neg;
+
+ b->d = tmp_d;
+ b->top = tmp_top;
+ b->dmax = tmp_dmax;
+ b->neg = tmp_neg;
+
+ a->flags = (flags_old_a & BN_FLG_MALLOCED) | (flags_old_b & BN_FLG_STATIC_DATA);
+ b->flags = (flags_old_b & BN_FLG_MALLOCED) | (flags_old_a & BN_FLG_STATIC_DATA);
+ bn_check_top(a);
+ bn_check_top(b);
+ }
+
+
void BN_clear(BIGNUM *a)
{
if (a->d != NULL)
- memset(a->d,0,a->max*sizeof(a->d[0]));
+ memset(a->d,0,a->dmax*sizeof(a->d[0]));
a->top=0;
a->neg=0;
+ bn_check_top(a);
}
-BN_ULONG BN_get_word(BIGNUM *a)
+BN_ULONG BN_get_word(const BIGNUM *a)
{
int i,n;
BN_ULONG ret=0;
n=BN_num_bytes(a);
- if (n > sizeof(BN_ULONG))
+ if (n > (int)sizeof(BN_ULONG))
return(BN_MASK2);
for (i=a->top-1; i>=0; i--)
{
int BN_set_word(BIGNUM *a, BN_ULONG w)
{
int i,n;
- if (bn_expand(a,sizeof(BN_ULONG)*8) == NULL) return(0);
+ if (bn_expand(a,(int)sizeof(BN_ULONG)*8) == NULL) return(0);
n=sizeof(BN_ULONG)/BN_BYTES;
a->neg=0;
a->d[i]=(BN_ULONG)w&BN_MASK2;
if (a->d[i] != 0) a->top=i+1;
}
+ bn_check_top(a);
return(1);
}
-/* ignore negative */
BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret)
{
unsigned int i,m;
i=((n-1)/BN_BYTES)+1;
m=((n-1)%(BN_BYTES));
ret->top=i;
+ ret->neg=0;
while (n-- > 0)
{
l=(l<<8L)| *(s++);
}
/* need to call this due to clear byte at top if avoiding
* having the top bit set (-ve number) */
- bn_fix_top(ret);
+ bn_correct_top(ret);
return(ret);
}
l=a->d[i/BN_BYTES];
*(to++)=(unsigned char)(l>>(8*(i%BN_BYTES)))&0xff;
}
+ bn_check_top(a);
return(n);
}
}
a->d[i]|=(((BN_ULONG)1)<<j);
+ bn_check_top(a);
return(1);
}
if (a->top <= i) return(0);
a->d[i]&=(~(((BN_ULONG)1)<<j));
- bn_fix_top(a);
+ bn_correct_top(a);
return(1);
}
a->top=w+1;
a->d[w]&= ~(BN_MASK2<<b);
}
- bn_fix_top(a);
+ bn_correct_top(a);
return(1);
}
-int bn_cmp_words(BN_ULONG *a, BN_ULONG *b, int n)
+int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n)
{
int i;
BN_ULONG aa,bb;
return(0);
}
+/* Here follows a specialised variants of bn_cmp_words(). It has the
+ property of performing the operation 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... */
+
+int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *b,
+ int cl, int dl)
+ {
+ int n,i;
+ n = cl-1;
+
+ if (dl < 0)
+ {
+ for (i=dl; i<0; i++)
+ {
+ if (b[n-i] != 0)
+ return -1; /* a < b */
+ }
+ }
+ if (dl > 0)
+ {
+ for (i=dl; i>0; i--)
+ {
+ if (a[n+i] != 0)
+ return 1; /* a > b */
+ }
+ }
+ return bn_cmp_words(a,b,cl);
+ }
+
+/* See the comments surrounding BIGNUM_C in bn.h */
+#ifdef BN_DEBUG
+const BIGNUM *BIGNUM_CONST(const BIGNUM_C *bn)
+ {
+ return (const BIGNUM *)bn;
+ }
+#endif
projects / openssl.git / blobdiff