* [including the GNU Public Licence.]
*/
+#ifndef BN_DEBUG
+# undef NDEBUG /* avoid conflicting definitions */
+# define NDEBUG
+#endif
+
+#include <assert.h>
#include <stdio.h>
#include "cryptlib.h"
#include "bn_lcl.h"
* 7 - 128 == 4096
* 8 - 256 == 8192
*/
-GLOBAL int bn_limit_bits=0;
-GLOBAL int bn_limit_num=8; /* (1<<bn_limit_bits) */
-GLOBAL int bn_limit_bits_low=0;
-GLOBAL int bn_limit_num_low=8; /* (1<<bn_limit_bits_low) */
-GLOBAL int bn_limit_bits_high=0;
-GLOBAL int bn_limit_num_high=8; /* (1<<bn_limit_bits_high) */
-GLOBAL int bn_limit_bits_mont=0;
-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)
{
int BN_num_bits_word(BN_ULONG l)
{
- static char bits[256]={
+ static const char bits[256]={
0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,
5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
}
}
-int BN_num_bits(BIGNUM *a)
+int BN_num_bits(const BIGNUM *a)
{
BN_ULONG l;
int i;
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]));
+ memset(a->d,0,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));
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)
{
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;
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 *internal_bn_expand(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)
+ 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 *)OPENSSL_malloc(sizeof(BN_ULONG)*(words+1));
+ if (A == NULL)
{
- BNerr(BN_F_BN_CTX_NEW,ERR_R_MALLOC_FAILURE);
+ 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)
+ {
+#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
+ }
- BN_CTX_init(ret);
- ret->flags=BN_FLG_MALLOCED;
- return(ret);
- }
+ /* Now need to zero any data between b->top and b->max */
-void BN_CTX_init(BN_CTX *ctx)
- {
- memset(ctx,0,sizeof(BN_CTX));
- ctx->tos=0;
- ctx->flags=0;
+ A= &(a[b->top]);
+ for (i=(words - 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=(words - 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);
+#endif
+
+ return(a);
}
-void BN_CTX_free(BN_CTX *c)
- {
- int i;
-
- if(c == NULL)
- return;
-
- for (i=0; i<BN_CTX_NUM; i++)
- BN_clear_free(&(c->bn[i]));
- if (c->flags & BN_FLG_MALLOCED)
- Free(c);
- }
+/* 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.
+ */
-BIGNUM *bn_expand2(BIGNUM *b, int words)
+BIGNUM *bn_dup_expand(const BIGNUM *b, int words)
{
- BN_ULONG *A,*B,*a;
- int i,j;
-
- bn_check_top(b);
+ BIGNUM *r = NULL;
- 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);
- }
-memset(A,0x5c,sizeof(BN_ULONG)*(words+1));
-#if 1
- B=b->d;
- /* Check if the previous number needs to be copied */
- if (B != NULL)
+ BN_ULONG *a = internal_bn_expand(b, words);
+
+ if (a)
{
- /* This lot is an unrolled loop to copy b->top
- * BN_ULONGs from B to A
- */
- for (i=b->top&(~7); i>0; i-=8)
+ r = BN_new();
+ if (r)
{
- 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;
+ r->top = b->top;
+ r->dmax = words;
+ r->neg = b->neg;
+ r->d = a;
}
- switch (b->top&7)
+ else
{
- 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 optimiser 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
- */
- ;
+ /* r == NULL, BN_new failure */
+ OPENSSL_free(a);
}
- Free(b->d);
}
+ /* If a == NULL, there was an error in allocation in
+ internal_bn_expand(), and NULL should be returned */
+ }
+ else
+ {
+ r = BN_dup(b);
+ }
- b->d=a;
- b->max=words;
+ return r;
+ }
- /* Now need to zero any data between b->top and b->max */
+/* This is an internal function that should not be used in applications.
+ * It ensures that 'b' has enough room for a 'words' word number number.
+ * It is mostly used by the various BIGNUM routines. If there is an error,
+ * NULL is returned. If not, 'b' is returned. */
- B= &(b->d[b->top]);
- j=(b->max - b->top) & ~7;
- for (i=0; i<j; i+=8)
- {
- B[0]=0; B[1]=0; B[2]=0; B[3]=0;
- B[4]=0; B[5]=0; B[6]=0; B[7]=0;
- B+=8;
- }
- j=(b->max - b->top) & 7;
- for (i=0; i<j; i++)
+BIGNUM *bn_expand2(BIGNUM *b, int words)
+ {
+ if (words > b->dmax)
+ {
+ BN_ULONG *a = internal_bn_expand(b, words);
+
+ if (a)
{
- B[0]=0;
- B++;
+ OPENSSL_free(b->d);
+ b->d=a;
+ b->dmax=words;
}
-#else
- memcpy(a->d,b->d,sizeof(b->d[0])*b->top);
-#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;} */
-
+ else
+ b = NULL;
}
- return(b);
+ return b;
}
-BIGNUM *BN_dup(BIGNUM *a)
+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);
+ return r;
}
-BIGNUM *BN_copy(BIGNUM *a, BIGNUM *b)
+BIGNUM *BN_copy(BIGNUM *a, const BIGNUM *b)
{
int i;
- BN_ULONG *A,*B;
+ BN_ULONG *A;
+ const BN_ULONG *B;
bn_check_top(b);
#if 1
A=a->d;
B=b->d;
- for (i=b->top&(~7); i>0; i-=8)
+ for (i=b->top>>2; i>0; i--,A+=4,B+=4)
{
- 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;
+ 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&7)
+ switch (b->top&3)
{
- 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 optimiser 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
- */
- ;
+ 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 */
}
#else
memcpy(a->d,b->d,sizeof(b->d[0])*b->top);
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_ULONG BN_get_word(BIGNUM *a)
+BN_ULONG BN_get_word(const BIGNUM *a)
{
int i,n;
BN_ULONG ret=0;
#ifndef SIXTY_FOUR_BIT /* the data item > unsigned long */
ret<<=BN_BITS4; /* stops the compiler complaining */
ret<<=BN_BITS4;
+#else
+ ret=0;
#endif
ret|=a->d[i];
}
#ifndef SIXTY_FOUR_BIT /* the data item > unsigned long */
w>>=BN_BITS4;
w>>=BN_BITS4;
+#else
+ w=0;
#endif
a->d[i]=(BN_ULONG)w&BN_MASK2;
if (a->d[i] != 0) a->top=i+1;
}
/* ignore negative */
-int BN_bn2bin(BIGNUM *a, unsigned char *to)
+int BN_bn2bin(const BIGNUM *a, unsigned char *to)
{
int n,i;
BN_ULONG l;
return(n);
}
-int BN_ucmp(BIGNUM *a, BIGNUM *b)
+int BN_ucmp(const BIGNUM *a, const BIGNUM *b)
{
int i;
BN_ULONG t1,t2,*ap,*bp;
return(0);
}
-int BN_cmp(BIGNUM *a, BIGNUM *b)
+int BN_cmp(const BIGNUM *a, const BIGNUM *b)
{
int i;
int gt,lt;
a->top=i+1;
}
- a->d[i]|=(1L<<j);
+ a->d[i]|=(((BN_ULONG)1)<<j);
return(1);
}
j=n%BN_BITS2;
if (a->top <= i) return(0);
- a->d[i]&=(~(1L<<j));
+ a->d[i]&=(~(((BN_ULONG)1)<<j));
bn_fix_top(a);
return(1);
}
-int BN_is_bit_set(BIGNUM *a, int n)
+int BN_is_bit_set(const BIGNUM *a, int n)
{
int i,j;
projects / openssl.git / blobdiff