X-Git-Url: https://git.openssl.org/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fbn%2Fbn_lib.c;h=0ad62652f6960798eef116aa95f787041d93bd9d;hp=5e3f3ed21029d6580cde3baf0aa7ebe2204c8da1;hb=e0bf5c11ea389fa3bacecdf4f3f9d22835a7508a;hpb=953937bdc624026eda5b36bcedc9dfacb9e85025 diff --git a/crypto/bn/bn_lib.c b/crypto/bn/bn_lib.c index 5e3f3ed210..0ad62652f6 100644 --- a/crypto/bn/bn_lib.c +++ b/crypto/bn/bn_lib.c @@ -56,11 +56,17 @@ * [including the GNU Public Licence.] */ +#ifndef BN_DEBUG +# undef NDEBUG /* avoid conflicting definitions */ +# define NDEBUG +#endif + +#include #include #include "cryptlib.h" #include "bn_lcl.h" -char *BN_version="Big Number" OPENSSL_VERSION_PTEXT; +const char *BN_version="Big Number" OPENSSL_VERSION_PTEXT; /* For a 32 bit machine * 2 - 4 == 128 @@ -71,17 +77,16 @@ char *BN_version="Big Number" OPENSSL_VERSION_PTEXT; * 7 - 128 == 4096 * 8 - 256 == 8192 */ -int bn_limit_bits=0; -int bn_limit_num=8; /* (1<= 0) { @@ -113,8 +118,7 @@ int mult,high,low,mont; } } -int BN_get_params(which) -int which; +int BN_get_params(int which) { if (which == 0) return(bn_limit_bits); else if (which == 1) return(bn_limit_bits_high); @@ -123,7 +127,7 @@ int which; else return(0); } -BIGNUM *BN_value_one() +BIGNUM *BN_value_one(void) { static BN_ULONG data_one=1L; static BIGNUM const_one={&data_one,1,1,0}; @@ -131,7 +135,7 @@ BIGNUM *BN_value_one() return(&const_one); } -char *BN_options() +char *BN_options(void) { static int init=0; static char data[16]; @@ -150,10 +154,9 @@ char *BN_options() return(data); } -int BN_num_bits_word(l) -BN_ULONG l; +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, @@ -238,8 +241,7 @@ BN_ULONG l; } } -int BN_num_bits(a) -BIGNUM *a; +int BN_num_bits(const BIGNUM *a) { BN_ULONG l; int i; @@ -248,57 +250,48 @@ BIGNUM *a; 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)); } -void BN_clear_free(a) -BIGNUM *a; +void BN_clear_free(BIGNUM *a) { int i; 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(a) -BIGNUM *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(a) -BIGNUM *a; +void BN_init(BIGNUM *a) { memset(a,0,sizeof(BIGNUM)); } -BIGNUM *BN_new() +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); @@ -306,169 +299,234 @@ BIGNUM *BN_new() 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() +/* 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. + * + * + */ + 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:-) + * + * + */ + 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(ctx) -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(c) -BN_CTX *c; - { - int i; - - if(c == NULL) - return; - - for (i=0; ibn[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(b, words) -BIGNUM *b; -int words; +BIGNUM *bn_dup_expand(const BIGNUM *b, int words) { - BN_ULONG *A,*B,*a; - int i,j; + BIGNUM *r = NULL; - 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); - } -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; imax - b->top) & 7; - for (i=0; i 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; id; 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); @@ -532,17 +561,15 @@ BIGNUM *b; return(a); } -void BN_clear(a) -BIGNUM *a; +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(a) -BIGNUM *a; +BN_ULONG BN_get_word(const BIGNUM *a) { int i,n; BN_ULONG ret=0; @@ -555,15 +582,15 @@ BIGNUM *a; #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]; } return(ret); } -int BN_set_word(a,w) -BIGNUM *a; -BN_ULONG w; +int BN_set_word(BIGNUM *a, BN_ULONG w) { int i,n; if (bn_expand(a,sizeof(BN_ULONG)*8) == NULL) return(0); @@ -581,6 +608,8 @@ BN_ULONG w; #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; @@ -589,10 +618,7 @@ BN_ULONG w; } /* ignore negative */ -BIGNUM *BN_bin2bn(s, len, ret) -unsigned char *s; -int len; -BIGNUM *ret; +BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret) { unsigned int i,m; unsigned int n; @@ -629,9 +655,7 @@ BIGNUM *ret; } /* ignore negative */ -int BN_bn2bin(a, to) -BIGNUM *a; -unsigned char *to; +int BN_bn2bin(const BIGNUM *a, unsigned char *to) { int n,i; BN_ULONG l; @@ -645,9 +669,7 @@ unsigned char *to; return(n); } -int BN_ucmp(a, b) -BIGNUM *a; -BIGNUM *b; +int BN_ucmp(const BIGNUM *a, const BIGNUM *b) { int i; BN_ULONG t1,t2,*ap,*bp; @@ -669,9 +691,7 @@ BIGNUM *b; return(0); } -int BN_cmp(a, b) -BIGNUM *a; -BIGNUM *b; +int BN_cmp(const BIGNUM *a, const BIGNUM *b) { int i; int gt,lt; @@ -712,9 +732,7 @@ BIGNUM *b; return(0); } -int BN_set_bit(a, n) -BIGNUM *a; -int n; +int BN_set_bit(BIGNUM *a, int n) { int i,j,k; @@ -728,13 +746,11 @@ int n; a->top=i+1; } - a->d[i]|=(1L<d[i]|=(((BN_ULONG)1)<top <= i) return(0); - a->d[i]&=(~(1L<d[i]&=(~(((BN_ULONG)1)<d[i]&(((BN_ULONG)1)<