diff options
Diffstat (limited to 'crypto/bn/bn_mul.c')
-rw-r--r-- | crypto/bn/bn_mul.c | 2004 |
1 files changed, 1001 insertions, 1003 deletions
diff --git a/crypto/bn/bn_mul.c b/crypto/bn/bn_mul.c index 12e5be80eb2b..b174850b6bb1 100644 --- a/crypto/bn/bn_mul.c +++ b/crypto/bn/bn_mul.c @@ -5,21 +5,21 @@ * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. - * + * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). - * + * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. - * + * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: @@ -34,10 +34,10 @@ * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). - * 4. If you include any Windows specific code (or a derivative thereof) from + * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" - * + * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE @@ -49,7 +49,7 @@ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. - * + * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence @@ -57,7 +57,7 @@ */ #ifndef BN_DEBUG -# undef NDEBUG /* avoid conflicting definitions */ +# undef NDEBUG /* avoid conflicting definitions */ # define NDEBUG #endif @@ -67,319 +67,353 @@ #include "bn_lcl.h" #if defined(OPENSSL_NO_ASM) || !defined(OPENSSL_BN_ASM_PART_WORDS) -/* 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. + */ BN_ULONG bn_sub_part_words(BN_ULONG *r, - const BN_ULONG *a, const BN_ULONG *b, - int cl, int dl) - { - BN_ULONG c, t; + const BN_ULONG *a, const BN_ULONG *b, + int cl, int dl) +{ + BN_ULONG c, t; - assert(cl >= 0); - c = bn_sub_words(r, a, b, cl); + assert(cl >= 0); + c = bn_sub_words(r, a, b, cl); - if (dl == 0) - return c; + if (dl == 0) + return c; - r += cl; - a += cl; - b += cl; + r += cl; + a += cl; + b += cl; - if (dl < 0) - { -#ifdef BN_COUNT - fprintf(stderr, " bn_sub_part_words %d + %d (dl < 0, c = %d)\n", cl, dl, c); -#endif - for (;;) - { - t = b[0]; - r[0] = (0-t-c)&BN_MASK2; - if (t != 0) c=1; - if (++dl >= 0) break; - - t = b[1]; - r[1] = (0-t-c)&BN_MASK2; - if (t != 0) c=1; - if (++dl >= 0) break; - - t = b[2]; - r[2] = (0-t-c)&BN_MASK2; - if (t != 0) c=1; - if (++dl >= 0) break; - - t = b[3]; - r[3] = (0-t-c)&BN_MASK2; - if (t != 0) c=1; - if (++dl >= 0) break; - - b += 4; - r += 4; - } - } - else - { - int save_dl = dl; -#ifdef BN_COUNT - fprintf(stderr, " bn_sub_part_words %d + %d (dl > 0, c = %d)\n", cl, dl, c); -#endif - while(c) - { - t = a[0]; - r[0] = (t-c)&BN_MASK2; - if (t != 0) c=0; - if (--dl <= 0) break; - - t = a[1]; - r[1] = (t-c)&BN_MASK2; - if (t != 0) c=0; - if (--dl <= 0) break; - - t = a[2]; - r[2] = (t-c)&BN_MASK2; - if (t != 0) c=0; - if (--dl <= 0) break; - - t = a[3]; - r[3] = (t-c)&BN_MASK2; - if (t != 0) c=0; - if (--dl <= 0) break; - - save_dl = dl; - a += 4; - r += 4; - } - if (dl > 0) - { -#ifdef BN_COUNT - fprintf(stderr, " bn_sub_part_words %d + %d (dl > 0, c == 0)\n", cl, dl); -#endif - if (save_dl > dl) - { - switch (save_dl - dl) - { - case 1: - r[1] = a[1]; - if (--dl <= 0) break; - case 2: - r[2] = a[2]; - if (--dl <= 0) break; - case 3: - r[3] = a[3]; - if (--dl <= 0) break; - } - a += 4; - r += 4; - } - } - if (dl > 0) - { -#ifdef BN_COUNT - fprintf(stderr, " bn_sub_part_words %d + %d (dl > 0, copy)\n", cl, dl); -#endif - for(;;) - { - r[0] = a[0]; - if (--dl <= 0) break; - r[1] = a[1]; - if (--dl <= 0) break; - r[2] = a[2]; - if (--dl <= 0) break; - r[3] = a[3]; - if (--dl <= 0) break; - - a += 4; - r += 4; - } - } - } - return c; - } + if (dl < 0) { +# ifdef BN_COUNT + fprintf(stderr, " bn_sub_part_words %d + %d (dl < 0, c = %d)\n", cl, + dl, c); +# endif + for (;;) { + t = b[0]; + r[0] = (0 - t - c) & BN_MASK2; + if (t != 0) + c = 1; + if (++dl >= 0) + break; + + t = b[1]; + r[1] = (0 - t - c) & BN_MASK2; + if (t != 0) + c = 1; + if (++dl >= 0) + break; + + t = b[2]; + r[2] = (0 - t - c) & BN_MASK2; + if (t != 0) + c = 1; + if (++dl >= 0) + break; + + t = b[3]; + r[3] = (0 - t - c) & BN_MASK2; + if (t != 0) + c = 1; + if (++dl >= 0) + break; + + b += 4; + r += 4; + } + } else { + int save_dl = dl; +# ifdef BN_COUNT + fprintf(stderr, " bn_sub_part_words %d + %d (dl > 0, c = %d)\n", cl, + dl, c); +# endif + while (c) { + t = a[0]; + r[0] = (t - c) & BN_MASK2; + if (t != 0) + c = 0; + if (--dl <= 0) + break; + + t = a[1]; + r[1] = (t - c) & BN_MASK2; + if (t != 0) + c = 0; + if (--dl <= 0) + break; + + t = a[2]; + r[2] = (t - c) & BN_MASK2; + if (t != 0) + c = 0; + if (--dl <= 0) + break; + + t = a[3]; + r[3] = (t - c) & BN_MASK2; + if (t != 0) + c = 0; + if (--dl <= 0) + break; + + save_dl = dl; + a += 4; + r += 4; + } + if (dl > 0) { +# ifdef BN_COUNT + fprintf(stderr, " bn_sub_part_words %d + %d (dl > 0, c == 0)\n", + cl, dl); +# endif + if (save_dl > dl) { + switch (save_dl - dl) { + case 1: + r[1] = a[1]; + if (--dl <= 0) + break; + case 2: + r[2] = a[2]; + if (--dl <= 0) + break; + case 3: + r[3] = a[3]; + if (--dl <= 0) + break; + } + a += 4; + r += 4; + } + } + if (dl > 0) { +# ifdef BN_COUNT + fprintf(stderr, " bn_sub_part_words %d + %d (dl > 0, copy)\n", + cl, dl); +# endif + for (;;) { + r[0] = a[0]; + if (--dl <= 0) + break; + r[1] = a[1]; + if (--dl <= 0) + break; + r[2] = a[2]; + if (--dl <= 0) + break; + r[3] = a[3]; + if (--dl <= 0) + break; + + a += 4; + r += 4; + } + } + } + return c; +} #endif BN_ULONG bn_add_part_words(BN_ULONG *r, - const BN_ULONG *a, const BN_ULONG *b, - int cl, int dl) - { - BN_ULONG c, l, t; + const BN_ULONG *a, const BN_ULONG *b, + int cl, int dl) +{ + BN_ULONG c, l, t; - assert(cl >= 0); - c = bn_add_words(r, a, b, cl); + assert(cl >= 0); + c = bn_add_words(r, a, b, cl); - if (dl == 0) - return c; + if (dl == 0) + return c; - r += cl; - a += cl; - b += cl; + r += cl; + a += cl; + b += cl; - if (dl < 0) - { - int save_dl = dl; + if (dl < 0) { + int save_dl = dl; #ifdef BN_COUNT - fprintf(stderr, " bn_add_part_words %d + %d (dl < 0, c = %d)\n", cl, dl, c); + fprintf(stderr, " bn_add_part_words %d + %d (dl < 0, c = %d)\n", cl, + dl, c); #endif - while (c) - { - l=(c+b[0])&BN_MASK2; - c=(l < c); - r[0]=l; - if (++dl >= 0) break; - - l=(c+b[1])&BN_MASK2; - c=(l < c); - r[1]=l; - if (++dl >= 0) break; - - l=(c+b[2])&BN_MASK2; - c=(l < c); - r[2]=l; - if (++dl >= 0) break; - - l=(c+b[3])&BN_MASK2; - c=(l < c); - r[3]=l; - if (++dl >= 0) break; - - save_dl = dl; - b+=4; - r+=4; - } - if (dl < 0) - { + while (c) { + l = (c + b[0]) & BN_MASK2; + c = (l < c); + r[0] = l; + if (++dl >= 0) + break; + + l = (c + b[1]) & BN_MASK2; + c = (l < c); + r[1] = l; + if (++dl >= 0) + break; + + l = (c + b[2]) & BN_MASK2; + c = (l < c); + r[2] = l; + if (++dl >= 0) + break; + + l = (c + b[3]) & BN_MASK2; + c = (l < c); + r[3] = l; + if (++dl >= 0) + break; + + save_dl = dl; + b += 4; + r += 4; + } + if (dl < 0) { #ifdef BN_COUNT - fprintf(stderr, " bn_add_part_words %d + %d (dl < 0, c == 0)\n", cl, dl); + fprintf(stderr, " bn_add_part_words %d + %d (dl < 0, c == 0)\n", + cl, dl); #endif - if (save_dl < dl) - { - switch (dl - save_dl) - { - case 1: - r[1] = b[1]; - if (++dl >= 0) break; - case 2: - r[2] = b[2]; - if (++dl >= 0) break; - case 3: - r[3] = b[3]; - if (++dl >= 0) break; - } - b += 4; - r += 4; - } - } - if (dl < 0) - { + if (save_dl < dl) { + switch (dl - save_dl) { + case 1: + r[1] = b[1]; + if (++dl >= 0) + break; + case 2: + r[2] = b[2]; + if (++dl >= 0) + break; + case 3: + r[3] = b[3]; + if (++dl >= 0) + break; + } + b += 4; + r += 4; + } + } + if (dl < 0) { #ifdef BN_COUNT - fprintf(stderr, " bn_add_part_words %d + %d (dl < 0, copy)\n", cl, dl); + fprintf(stderr, " bn_add_part_words %d + %d (dl < 0, copy)\n", + cl, dl); #endif - for(;;) - { - r[0] = b[0]; - if (++dl >= 0) break; - r[1] = b[1]; - if (++dl >= 0) break; - r[2] = b[2]; - if (++dl >= 0) break; - r[3] = b[3]; - if (++dl >= 0) break; - - b += 4; - r += 4; - } - } - } - else - { - int save_dl = dl; + for (;;) { + r[0] = b[0]; + if (++dl >= 0) + break; + r[1] = b[1]; + if (++dl >= 0) + break; + r[2] = b[2]; + if (++dl >= 0) + break; + r[3] = b[3]; + if (++dl >= 0) + break; + + b += 4; + r += 4; + } + } + } else { + int save_dl = dl; #ifdef BN_COUNT - fprintf(stderr, " bn_add_part_words %d + %d (dl > 0)\n", cl, dl); + fprintf(stderr, " bn_add_part_words %d + %d (dl > 0)\n", cl, dl); #endif - while (c) - { - t=(a[0]+c)&BN_MASK2; - c=(t < c); - r[0]=t; - if (--dl <= 0) break; - - t=(a[1]+c)&BN_MASK2; - c=(t < c); - r[1]=t; - if (--dl <= 0) break; - - t=(a[2]+c)&BN_MASK2; - c=(t < c); - r[2]=t; - if (--dl <= 0) break; - - t=(a[3]+c)&BN_MASK2; - c=(t < c); - r[3]=t; - if (--dl <= 0) break; - - save_dl = dl; - a+=4; - r+=4; - } + while (c) { + t = (a[0] + c) & BN_MASK2; + c = (t < c); + r[0] = t; + if (--dl <= 0) + break; + + t = (a[1] + c) & BN_MASK2; + c = (t < c); + r[1] = t; + if (--dl <= 0) + break; + + t = (a[2] + c) & BN_MASK2; + c = (t < c); + r[2] = t; + if (--dl <= 0) + break; + + t = (a[3] + c) & BN_MASK2; + c = (t < c); + r[3] = t; + if (--dl <= 0) + break; + + save_dl = dl; + a += 4; + r += 4; + } #ifdef BN_COUNT - fprintf(stderr, " bn_add_part_words %d + %d (dl > 0, c == 0)\n", cl, dl); + fprintf(stderr, " bn_add_part_words %d + %d (dl > 0, c == 0)\n", cl, + dl); #endif - if (dl > 0) - { - if (save_dl > dl) - { - switch (save_dl - dl) - { - case 1: - r[1] = a[1]; - if (--dl <= 0) break; - case 2: - r[2] = a[2]; - if (--dl <= 0) break; - case 3: - r[3] = a[3]; - if (--dl <= 0) break; - } - a += 4; - r += 4; - } - } - if (dl > 0) - { + if (dl > 0) { + if (save_dl > dl) { + switch (save_dl - dl) { + case 1: + r[1] = a[1]; + if (--dl <= 0) + break; + case 2: + r[2] = a[2]; + if (--dl <= 0) + break; + case 3: + r[3] = a[3]; + if (--dl <= 0) + break; + } + a += 4; + r += 4; + } + } + if (dl > 0) { #ifdef BN_COUNT - fprintf(stderr, " bn_add_part_words %d + %d (dl > 0, copy)\n", cl, dl); + fprintf(stderr, " bn_add_part_words %d + %d (dl > 0, copy)\n", + cl, dl); #endif - for(;;) - { - r[0] = a[0]; - if (--dl <= 0) break; - r[1] = a[1]; - if (--dl <= 0) break; - r[2] = a[2]; - if (--dl <= 0) break; - r[3] = a[3]; - if (--dl <= 0) break; - - a += 4; - r += 4; - } - } - } - return c; - } + for (;;) { + r[0] = a[0]; + if (--dl <= 0) + break; + r[1] = a[1]; + if (--dl <= 0) + break; + r[2] = a[2]; + if (--dl <= 0) + break; + r[3] = a[3]; + if (--dl <= 0) + break; + + a += 4; + r += 4; + } + } + } + return c; +} #ifdef BN_RECURSION -/* Karatsuba recursive multiplication algorithm - * (cf. Knuth, The Art of Computer Programming, Vol. 2) */ +/* + * Karatsuba recursive multiplication algorithm (cf. Knuth, The Art of + * Computer Programming, Vol. 2) + */ -/* r is 2*n2 words in size, +/*- + * 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. @@ -391,776 +425,740 @@ BN_ULONG bn_add_part_words(BN_ULONG *r, */ /* dnX may not be positive, but n2/2+dnX has to be */ 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; - int tna=n+dna, tnb=n+dnb; - unsigned int neg,zero; - BN_ULONG ln,lo,*p; + int dna, int dnb, BN_ULONG *t) +{ + int n = n2 / 2, c1, c2; + int tna = n + dna, tnb = n + dnb; + unsigned int neg, zero; + BN_ULONG ln, lo, *p; # ifdef BN_COUNT - fprintf(stderr," bn_mul_recursive %d%+d * %d%+d\n",n2,dna,n2,dnb); + fprintf(stderr, " bn_mul_recursive %d%+d * %d%+d\n", n2, dna, n2, dnb); # endif # ifdef BN_MUL_COMBA # if 0 - if (n2 == 4) - { - bn_mul_comba4(r,a,b); - return; - } + if (n2 == 4) { + bn_mul_comba4(r, a, b); + return; + } # endif - /* 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; - } -# endif /* BN_MUL_COMBA */ - /* 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) - memset(&r[2*n2 + dna + dnb], 0, - sizeof(BN_ULONG) * -(dna + dnb)); - return; - } - /* 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); /* - */ - 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); /* + */ - neg=1; - break; - case -1: - case 0: - case 1: - 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); /* - */ - neg=1; - break; - case 3: - zero=1; - 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); - break; - } + /* + * 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; + } +# endif /* BN_MUL_COMBA */ + /* 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) + memset(&r[2 * n2 + dna + dnb], 0, + sizeof(BN_ULONG) * -(dna + dnb)); + return; + } + /* 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); /* - */ + 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); /* + */ + neg = 1; + break; + case -1: + case 0: + case 1: + 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); /* - */ + neg = 1; + break; + case 3: + zero = 1; + 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); + break; + } # ifdef BN_MUL_COMBA - if (n == 4 && dna == 0 && dnb == 0) /* XXX: bn_mul_comba4 could take - extra args to do this well */ - { - if (!zero) - bn_mul_comba4(&(t[n2]),t,&(t[n])); - else - memset(&(t[n2]),0,8*sizeof(BN_ULONG)); - - 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 */ - { - if (!zero) - bn_mul_comba8(&(t[n2]),t,&(t[n])); - else - memset(&(t[n2]),0,16*sizeof(BN_ULONG)); - - bn_mul_comba8(r,a,b); - bn_mul_comba8(&(r[n2]),&(a[n]),&(b[n])); - } - else -# endif /* BN_MUL_COMBA */ - { - p= &(t[n2*2]); - if (!zero) - bn_mul_recursive(&(t[n2]),t,&(t[n]),n,0,0,p); - else - memset(&(t[n2]),0,n2*sizeof(BN_ULONG)); - bn_mul_recursive(r,a,b,n,0,0,p); - 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]) - */ - - c1=(int)(bn_add_words(t,r,&(r[n2]),n2)); - - if (neg) /* if t[32] is negative */ - { - c1-=(int)(bn_sub_words(&(t[n2]),t,&(t[n2]),n2)); - } - else - { - /* 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 - */ - c1+=(int)(bn_add_words(&(r[n]),&(r[n]),&(t[n2]),n2)); - if (c1) - { - p= &(r[n+n2]); - lo= *p; - ln=(lo+c1)&BN_MASK2; - *p=ln; - - /* The overflow will stop before we over write - * words we should not overwrite */ - if (ln < (BN_ULONG)c1) - { - do { - p++; - lo= *p; - ln=(lo+1)&BN_MASK2; - *p=ln; - } while (ln == 0); - } - } - } - -/* n+tn is the word length - * t needs to be n*4 is size, as does r */ + if (n == 4 && dna == 0 && dnb == 0) { /* XXX: bn_mul_comba4 could take + * extra args to do this well */ + if (!zero) + bn_mul_comba4(&(t[n2]), t, &(t[n])); + else + memset(&(t[n2]), 0, 8 * sizeof(BN_ULONG)); + + 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 */ + if (!zero) + bn_mul_comba8(&(t[n2]), t, &(t[n])); + else + memset(&(t[n2]), 0, 16 * sizeof(BN_ULONG)); + + bn_mul_comba8(r, a, b); + bn_mul_comba8(&(r[n2]), &(a[n]), &(b[n])); + } else +# endif /* BN_MUL_COMBA */ + { + p = &(t[n2 * 2]); + if (!zero) + bn_mul_recursive(&(t[n2]), t, &(t[n]), n, 0, 0, p); + else + memset(&(t[n2]), 0, n2 * sizeof(BN_ULONG)); + bn_mul_recursive(r, a, b, n, 0, 0, p); + 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]) + */ + + c1 = (int)(bn_add_words(t, r, &(r[n2]), n2)); + + if (neg) { /* if t[32] is negative */ + c1 -= (int)(bn_sub_words(&(t[n2]), t, &(t[n2]), n2)); + } else { + /* 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 + */ + c1 += (int)(bn_add_words(&(r[n]), &(r[n]), &(t[n2]), n2)); + if (c1) { + p = &(r[n + n2]); + lo = *p; + ln = (lo + c1) & BN_MASK2; + *p = ln; + + /* + * The overflow will stop before we over write words we should not + * overwrite + */ + if (ln < (BN_ULONG)c1) { + do { + p++; + lo = *p; + ln = (lo + 1) & BN_MASK2; + *p = ln; + } while (ln == 0); + } + } +} + +/* + * 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 */ 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; - int c1,c2,neg; - BN_ULONG ln,lo,*p; + int tna, int tnb, BN_ULONG *t) +{ + int i, j, n2 = n * 2; + int c1, c2, neg; + BN_ULONG ln, lo, *p; # ifdef BN_COUNT - fprintf(stderr," bn_mul_part_recursive (%d%+d) * (%d%+d)\n", - n, tna, n, tnb); + fprintf(stderr, " bn_mul_part_recursive (%d%+d) * (%d%+d)\n", + n, tna, n, tnb); # endif - if (n < 8) - { - bn_mul_normal(r,a,n+tna,b,n+tnb); - return; - } - - /* 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); /* - */ - break; - case -3: - /* 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); /* + */ - neg=1; - break; - case -1: - case 0: - case 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); /* - */ - neg=1; - break; - case 3: - /* 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); - break; - } - /* The zero case isn't yet implemented here. The speedup - would probably be negligible. */ + if (n < 8) { + bn_mul_normal(r, a, n + tna, b, n + tnb); + return; + } + + /* 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); /* - */ + break; + case -3: + /* 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); /* + */ + neg = 1; + break; + case -1: + case 0: + case 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); /* - */ + neg = 1; + break; + case 3: + /* 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); + break; + } + /* + * The zero case isn't yet implemented here. The speedup would probably + * be negligible. + */ # if 0 - if (n == 4) - { - bn_mul_comba4(&(t[n2]),t,&(t[n])); - bn_mul_comba4(r,a,b); - bn_mul_normal(&(r[n2]),&(a[n]),tn,&(b[n]),tn); - memset(&(r[n2+tn*2]),0,sizeof(BN_ULONG)*(n2-tn*2)); - } - else + if (n == 4) { + bn_mul_comba4(&(t[n2]), t, &(t[n])); + bn_mul_comba4(r, a, b); + bn_mul_normal(&(r[n2]), &(a[n]), tn, &(b[n]), tn); + memset(&(r[n2 + tn * 2]), 0, sizeof(BN_ULONG) * (n2 - tn * 2)); + } else # endif - if (n == 8) - { - bn_mul_comba8(&(t[n2]),t,&(t[n])); - bn_mul_comba8(r,a,b); - bn_mul_normal(&(r[n2]),&(a[n]),tna,&(b[n]),tnb); - memset(&(r[n2+tna+tnb]),0,sizeof(BN_ULONG)*(n2-tna-tnb)); - } - else - { - p= &(t[n2*2]); - 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 (tna > tnb) - j = tna - i; - else - j = tnb - i; - if (j == 0) - { - bn_mul_recursive(&(r[n2]),&(a[n]),&(b[n]), - i,tna-i,tnb-i,p); - memset(&(r[n2+i*2]),0,sizeof(BN_ULONG)*(n2-i*2)); - } - else if (j > 0) /* eg, n == 16, i == 8 and tn == 11 */ - { - bn_mul_part_recursive(&(r[n2]),&(a[n]),&(b[n]), - i,tna-i,tnb-i,p); - memset(&(r[n2+tna+tnb]),0, - sizeof(BN_ULONG)*(n2-tna-tnb)); - } - else /* (j < 0) eg, n == 16, i == 8 and tn == 5 */ - { - memset(&(r[n2]),0,sizeof(BN_ULONG)*n2); - if (tna < BN_MUL_RECURSIVE_SIZE_NORMAL - && tnb < BN_MUL_RECURSIVE_SIZE_NORMAL) - { - bn_mul_normal(&(r[n2]),&(a[n]),tna,&(b[n]),tnb); - } - else - { - for (;;) - { - i/=2; - /* 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); - break; - } - else if (i == tna || i == tnb) - { - bn_mul_recursive(&(r[n2]), - &(a[n]),&(b[n]), - i,tna-i,tnb-i,p); - break; - } - } - } - } - } - - /* 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 */ - { - c1-=(int)(bn_sub_words(&(t[n2]),t,&(t[n2]),n2)); - } - else - { - /* 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 - */ - c1+=(int)(bn_add_words(&(r[n]),&(r[n]),&(t[n2]),n2)); - if (c1) - { - p= &(r[n+n2]); - lo= *p; - ln=(lo+c1)&BN_MASK2; - *p=ln; - - /* The overflow will stop before we over write - * words we should not overwrite */ - if (ln < (BN_ULONG)c1) - { - do { - p++; - lo= *p; - ln=(lo+1)&BN_MASK2; - *p=ln; - } while (ln == 0); - } - } - } - -/* a and b must be the same size, which is n2. + if (n == 8) { + bn_mul_comba8(&(t[n2]), t, &(t[n])); + bn_mul_comba8(r, a, b); + bn_mul_normal(&(r[n2]), &(a[n]), tna, &(b[n]), tnb); + memset(&(r[n2 + tna + tnb]), 0, sizeof(BN_ULONG) * (n2 - tna - tnb)); + } else { + p = &(t[n2 * 2]); + 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 (tna > tnb) + j = tna - i; + else + j = tnb - i; + if (j == 0) { + bn_mul_recursive(&(r[n2]), &(a[n]), &(b[n]), + i, tna - i, tnb - i, p); + memset(&(r[n2 + i * 2]), 0, sizeof(BN_ULONG) * (n2 - i * 2)); + } else if (j > 0) { /* eg, n == 16, i == 8 and tn == 11 */ + bn_mul_part_recursive(&(r[n2]), &(a[n]), &(b[n]), + i, tna - i, tnb - i, p); + memset(&(r[n2 + tna + tnb]), 0, + sizeof(BN_ULONG) * (n2 - tna - tnb)); + } else { /* (j < 0) eg, n == 16, i == 8 and tn == 5 */ + + memset(&(r[n2]), 0, sizeof(BN_ULONG) * n2); + if (tna < BN_MUL_RECURSIVE_SIZE_NORMAL + && tnb < BN_MUL_RECURSIVE_SIZE_NORMAL) { + bn_mul_normal(&(r[n2]), &(a[n]), tna, &(b[n]), tnb); + } else { + for (;;) { + i /= 2; + /* + * 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); + break; + } else if (i == tna || i == tnb) { + bn_mul_recursive(&(r[n2]), + &(a[n]), &(b[n]), + i, tna - i, tnb - i, p); + break; + } + } + } + } + } + + /*- + * 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 */ + c1 -= (int)(bn_sub_words(&(t[n2]), t, &(t[n2]), n2)); + } else { + /* 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 + */ + c1 += (int)(bn_add_words(&(r[n]), &(r[n]), &(t[n2]), n2)); + if (c1) { + p = &(r[n + n2]); + lo = *p; + ln = (lo + c1) & BN_MASK2; + *p = ln; + + /* + * The overflow will stop before we over write words we should not + * overwrite + */ + if (ln < (BN_ULONG)c1) { + do { + p++; + lo = *p; + ln = (lo + 1) & BN_MASK2; + *p = ln; + } while (ln == 0); + } + } +} + +/*- + * a and b must be the same size, which is n2. * r needs to be n2 words and t needs to be n2*2 */ void bn_mul_low_recursive(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n2, - BN_ULONG *t) - { - int n=n2/2; + BN_ULONG *t) +{ + int n = n2 / 2; # ifdef BN_COUNT - fprintf(stderr," bn_mul_low_recursive %d * %d\n",n2,n2); + fprintf(stderr, " bn_mul_low_recursive %d * %d\n", n2, n2); # endif - bn_mul_recursive(r,a,b,n,0,0,&(t[0])); - if (n >= BN_MUL_LOW_RECURSIVE_SIZE_NORMAL) - { - bn_mul_low_recursive(&(t[0]),&(a[0]),&(b[n]),n,&(t[n2])); - bn_add_words(&(r[n]),&(r[n]),&(t[0]),n); - bn_mul_low_recursive(&(t[0]),&(a[n]),&(b[0]),n,&(t[n2])); - bn_add_words(&(r[n]),&(r[n]),&(t[0]),n); - } - else - { - bn_mul_low_normal(&(t[0]),&(a[0]),&(b[n]),n); - bn_mul_low_normal(&(t[n]),&(a[n]),&(b[0]),n); - bn_add_words(&(r[n]),&(r[n]),&(t[0]),n); - bn_add_words(&(r[n]),&(r[n]),&(t[n]),n); - } - } - -/* a and b must be the same size, which is n2. + bn_mul_recursive(r, a, b, n, 0, 0, &(t[0])); + if (n >= BN_MUL_LOW_RECURSIVE_SIZE_NORMAL) { + bn_mul_low_recursive(&(t[0]), &(a[0]), &(b[n]), n, &(t[n2])); + bn_add_words(&(r[n]), &(r[n]), &(t[0]), n); + bn_mul_low_recursive(&(t[0]), &(a[n]), &(b[0]), n, &(t[n2])); + bn_add_words(&(r[n]), &(r[n]), &(t[0]), n); + } else { + bn_mul_low_normal(&(t[0]), &(a[0]), &(b[n]), n); + bn_mul_low_normal(&(t[n]), &(a[n]), &(b[0]), n); + bn_add_words(&(r[n]), &(r[n]), &(t[0]), n); + bn_add_words(&(r[n]), &(r[n]), &(t[n]), n); + } +} + +/*- + * a and b must be the same size, which is n2. * r needs to be n2 words and t needs to be n2*2 * l is the low words of the output. * t needs to be n2*3 */ void bn_mul_high(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, BN_ULONG *l, int n2, - BN_ULONG *t) - { - int i,n; - int c1,c2; - int neg,oneg,zero; - BN_ULONG ll,lc,*lp,*mp; + BN_ULONG *t) +{ + int i, n; + int c1, c2; + int neg, oneg, zero; + BN_ULONG ll, lc, *lp, *mp; # ifdef BN_COUNT - fprintf(stderr," bn_mul_high %d * %d\n",n2,n2); + fprintf(stderr, " bn_mul_high %d * %d\n", n2, n2); # endif - n=n2/2; - - /* Calculate (al-ah)*(bh-bl) */ - neg=zero=0; - c1=bn_cmp_words(&(a[0]),&(a[n]),n); - c2=bn_cmp_words(&(b[n]),&(b[0]),n); - switch (c1*3+c2) - { - case -4: - bn_sub_words(&(r[0]),&(a[n]),&(a[0]),n); - bn_sub_words(&(r[n]),&(b[0]),&(b[n]),n); - break; - case -3: - zero=1; - break; - case -2: - bn_sub_words(&(r[0]),&(a[n]),&(a[0]),n); - bn_sub_words(&(r[n]),&(b[n]),&(b[0]),n); - neg=1; - break; - case -1: - case 0: - case 1: - zero=1; - break; - case 2: - bn_sub_words(&(r[0]),&(a[0]),&(a[n]),n); - bn_sub_words(&(r[n]),&(b[0]),&(b[n]),n); - neg=1; - break; - case 3: - zero=1; - break; - case 4: - bn_sub_words(&(r[0]),&(a[0]),&(a[n]),n); - bn_sub_words(&(r[n]),&(b[n]),&(b[0]),n); - break; - } - - oneg=neg; - /* t[10] = (a[0]-a[1])*(b[1]-b[0]) */ - /* r[10] = (a[1]*b[1]) */ + n = n2 / 2; + + /* Calculate (al-ah)*(bh-bl) */ + neg = zero = 0; + c1 = bn_cmp_words(&(a[0]), &(a[n]), n); + c2 = bn_cmp_words(&(b[n]), &(b[0]), n); + switch (c1 * 3 + c2) { + case -4: + bn_sub_words(&(r[0]), &(a[n]), &(a[0]), n); + bn_sub_words(&(r[n]), &(b[0]), &(b[n]), n); + break; + case -3: + zero = 1; + break; + case -2: + bn_sub_words(&(r[0]), &(a[n]), &(a[0]), n); + bn_sub_words(&(r[n]), &(b[n]), &(b[0]), n); + neg = 1; + break; + case -1: + case 0: + case 1: + zero = 1; + break; + case 2: + bn_sub_words(&(r[0]), &(a[0]), &(a[n]), n); + bn_sub_words(&(r[n]), &(b[0]), &(b[n]), n); + neg = 1; + break; + case 3: + zero = 1; + break; + case 4: + bn_sub_words(&(r[0]), &(a[0]), &(a[n]), n); + bn_sub_words(&(r[n]), &(b[n]), &(b[0]), n); + break; + } + + oneg = neg; + /* t[10] = (a[0]-a[1])*(b[1]-b[0]) */ + /* r[10] = (a[1]*b[1]) */ # ifdef BN_MUL_COMBA - if (n == 8) - { - bn_mul_comba8(&(t[0]),&(r[0]),&(r[n])); - bn_mul_comba8(r,&(a[n]),&(b[n])); - } - else + if (n == 8) { + bn_mul_comba8(&(t[0]), &(r[0]), &(r[n])); + bn_mul_comba8(r, &(a[n]), &(b[n])); + } else # endif - { - bn_mul_recursive(&(t[0]),&(r[0]),&(r[n]),n,0,0,&(t[n2])); - bn_mul_recursive(r,&(a[n]),&(b[n]),n,0,0,&(t[n2])); - } - - /* s0 == low(al*bl) - * s1 == low(ah*bh)+low((al-ah)*(bh-bl))+low(al*bl)+high(al*bl) - * We know s0 and s1 so the only unknown is high(al*bl) - * high(al*bl) == s1 - low(ah*bh+s0+(al-ah)*(bh-bl)) - * high(al*bl) == s1 - (r[0]+l[0]+t[0]) - */ - if (l != NULL) - { - lp= &(t[n2+n]); - c1=(int)(bn_add_words(lp,&(r[0]),&(l[0]),n)); - } - else - { - c1=0; - lp= &(r[0]); - } - - if (neg) - neg=(int)(bn_sub_words(&(t[n2]),lp,&(t[0]),n)); - else - { - bn_add_words(&(t[n2]),lp,&(t[0]),n); - neg=0; - } - - if (l != NULL) - { - bn_sub_words(&(t[n2+n]),&(l[n]),&(t[n2]),n); - } - else - { - lp= &(t[n2+n]); - mp= &(t[n2]); - for (i=0; i<n; i++) - lp[i]=((~mp[i])+1)&BN_MASK2; - } - - /* s[0] = low(al*bl) - * t[3] = high(al*bl) - * t[10] = (a[0]-a[1])*(b[1]-b[0]) neg is the sign - * r[10] = (a[1]*b[1]) - */ - /* R[10] = al*bl - * R[21] = al*bl + ah*bh + (a[0]-a[1])*(b[1]-b[0]) - * R[32] = ah*bh - */ - /* R[1]=t[3]+l[0]+r[0](+-)t[0] (have carry/borrow) - * R[2]=r[0]+t[3]+r[1](+-)t[1] (have carry/borrow) - * R[3]=r[1]+(carry/borrow) - */ - if (l != NULL) - { - lp= &(t[n2]); - c1= (int)(bn_add_words(lp,&(t[n2+n]),&(l[0]),n)); - } - else - { - lp= &(t[n2+n]); - c1=0; - } - c1+=(int)(bn_add_words(&(t[n2]),lp, &(r[0]),n)); - if (oneg) - c1-=(int)(bn_sub_words(&(t[n2]),&(t[n2]),&(t[0]),n)); - else - c1+=(int)(bn_add_words(&(t[n2]),&(t[n2]),&(t[0]),n)); - - c2 =(int)(bn_add_words(&(r[0]),&(r[0]),&(t[n2+n]),n)); - c2+=(int)(bn_add_words(&(r[0]),&(r[0]),&(r[n]),n)); - if (oneg) - c2-=(int)(bn_sub_words(&(r[0]),&(r[0]),&(t[n]),n)); - else - c2+=(int)(bn_add_words(&(r[0]),&(r[0]),&(t[n]),n)); - - if (c1 != 0) /* Add starting at r[0], could be +ve or -ve */ - { - i=0; - if (c1 > 0) - { - lc=c1; - do { - ll=(r[i]+lc)&BN_MASK2; - r[i++]=ll; - lc=(lc > ll); - } while (lc); - } - else - { - lc= -c1; - do { - ll=r[i]; - r[i++]=(ll-lc)&BN_MASK2; - lc=(lc > ll); - } while (lc); - } - } - if (c2 != 0) /* Add starting at r[1] */ - { - i=n; - if (c2 > 0) - { - lc=c2; - do { - ll=(r[i]+lc)&BN_MASK2; - r[i++]=ll; - lc=(lc > ll); - } while (lc); - } - else - { - lc= -c2; - do { - ll=r[i]; - r[i++]=(ll-lc)&BN_MASK2; - lc=(lc > ll); - } while (lc); - } - } - } -#endif /* BN_RECURSION */ + { + bn_mul_recursive(&(t[0]), &(r[0]), &(r[n]), n, 0, 0, &(t[n2])); + bn_mul_recursive(r, &(a[n]), &(b[n]), n, 0, 0, &(t[n2])); + } + + /*- + * s0 == low(al*bl) + * s1 == low(ah*bh)+low((al-ah)*(bh-bl))+low(al*bl)+high(al*bl) + * We know s0 and s1 so the only unknown is high(al*bl) + * high(al*bl) == s1 - low(ah*bh+s0+(al-ah)*(bh-bl)) + * high(al*bl) == s1 - (r[0]+l[0]+t[0]) + */ + if (l != NULL) { + lp = &(t[n2 + n]); + c1 = (int)(bn_add_words(lp, &(r[0]), &(l[0]), n)); + } else { + c1 = 0; + lp = &(r[0]); + } + + if (neg) + neg = (int)(bn_sub_words(&(t[n2]), lp, &(t[0]), n)); + else { + bn_add_words(&(t[n2]), lp, &(t[0]), n); + neg = 0; + } + + if (l != NULL) { + bn_sub_words(&(t[n2 + n]), &(l[n]), &(t[n2]), n); + } else { + lp = &(t[n2 + n]); + mp = &(t[n2]); + for (i = 0; i < n; i++) + lp[i] = ((~mp[i]) + 1) & BN_MASK2; + } + + /*- + * s[0] = low(al*bl) + * t[3] = high(al*bl) + * t[10] = (a[0]-a[1])*(b[1]-b[0]) neg is the sign + * r[10] = (a[1]*b[1]) + */ + /*- + * R[10] = al*bl + * R[21] = al*bl + ah*bh + (a[0]-a[1])*(b[1]-b[0]) + * R[32] = ah*bh + */ + /*- + * R[1]=t[3]+l[0]+r[0](+-)t[0] (have carry/borrow) + * R[2]=r[0]+t[3]+r[1](+-)t[1] (have carry/borrow) + * R[3]=r[1]+(carry/borrow) + */ + if (l != NULL) { + lp = &(t[n2]); + c1 = (int)(bn_add_words(lp, &(t[n2 + n]), &(l[0]), n)); + } else { + lp = &(t[n2 + n]); + c1 = 0; + } + c1 += (int)(bn_add_words(&(t[n2]), lp, &(r[0]), n)); + if (oneg) + c1 -= (int)(bn_sub_words(&(t[n2]), &(t[n2]), &(t[0]), n)); + else + c1 += (int)(bn_add_words(&(t[n2]), &(t[n2]), &(t[0]), n)); + + c2 = (int)(bn_add_words(&(r[0]), &(r[0]), &(t[n2 + n]), n)); + c2 += (int)(bn_add_words(&(r[0]), &(r[0]), &(r[n]), n)); + if (oneg) + c2 -= (int)(bn_sub_words(&(r[0]), &(r[0]), &(t[n]), n)); + else + c2 += (int)(bn_add_words(&(r[0]), &(r[0]), &(t[n]), n)); + + if (c1 != 0) { /* Add starting at r[0], could be +ve or -ve */ + i = 0; + if (c1 > 0) { + lc = c1; + do { + ll = (r[i] + lc) & BN_MASK2; + r[i++] = ll; + lc = (lc > ll); + } while (lc); + } else { + lc = -c1; + do { + ll = r[i]; + r[i++] = (ll - lc) & BN_MASK2; + lc = (lc > ll); + } while (lc); + } + } + if (c2 != 0) { /* Add starting at r[1] */ + i = n; + if (c2 > 0) { + lc = c2; + do { + ll = (r[i] + lc) & BN_MASK2; + r[i++] = ll; + lc = (lc > ll); + } while (lc); + } else { + lc = -c2; + do { + ll = r[i]; + r[i++] = (ll - lc) & BN_MASK2; + lc = (lc > ll); + } while (lc); + } + } +} +#endif /* BN_RECURSION */ int BN_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx) - { - int ret=0; - int top,al,bl; - BIGNUM *rr; +{ + int ret = 0; + int top, al, bl; + BIGNUM *rr; #if defined(BN_MUL_COMBA) || defined(BN_RECURSION) - int i; + int i; #endif #ifdef BN_RECURSION - BIGNUM *t=NULL; - int j=0,k; + BIGNUM *t = NULL; + int j = 0, k; #endif #ifdef BN_COUNT - fprintf(stderr,"BN_mul %d * %d\n",a->top,b->top); + fprintf(stderr, "BN_mul %d * %d\n", a->top, b->top); #endif - bn_check_top(a); - bn_check_top(b); - bn_check_top(r); - - al=a->top; - bl=b->top; - - if ((al == 0) || (bl == 0)) - { - BN_zero(r); - return(1); - } - top=al+bl; - - BN_CTX_start(ctx); - if ((r == a) || (r == b)) - { - if ((rr = BN_CTX_get(ctx)) == NULL) goto err; - } - else - rr = r; - rr->neg=a->neg^b->neg; + bn_check_top(a); + bn_check_top(b); + bn_check_top(r); + + al = a->top; + bl = b->top; + + if ((al == 0) || (bl == 0)) { + BN_zero(r); + return (1); + } + top = al + bl; + + BN_CTX_start(ctx); + if ((r == a) || (r == b)) { + if ((rr = BN_CTX_get(ctx)) == NULL) + goto err; + } else + rr = r; + rr->neg = a->neg ^ b->neg; #if defined(BN_MUL_COMBA) || defined(BN_RECURSION) - i = al-bl; + i = al - bl; #endif #ifdef BN_MUL_COMBA - if (i == 0) - { + if (i == 0) { # if 0 - if (al == 4) - { - if (bn_wexpand(rr,8) == NULL) goto err; - rr->top=8; - bn_mul_comba4(rr->d,a->d,b->d); - goto end; - } + if (al == 4) { + if (bn_wexpand(rr, 8) == NULL) + goto err; + rr->top = 8; + bn_mul_comba4(rr->d, a->d, b->d); + goto end; + } # endif - if (al == 8) - { - if (bn_wexpand(rr,16) == NULL) goto err; - rr->top=16; - bn_mul_comba8(rr->d,a->d,b->d); - goto end; - } - } -#endif /* BN_MUL_COMBA */ + if (al == 8) { + if (bn_wexpand(rr, 16) == NULL) + goto err; + rr->top = 16; + bn_mul_comba8(rr->d, a->d, b->d); + goto end; + } + } +#endif /* BN_MUL_COMBA */ #ifdef BN_RECURSION - if ((al >= BN_MULL_SIZE_NORMAL) && (bl >= BN_MULL_SIZE_NORMAL)) - { - if (i >= -1 && i <= 1) - { - /* Find out the power of two lower or equal - to the longest of the two numbers */ - if (i >= 0) - { - j = BN_num_bits_word((BN_ULONG)al); - } - if (i == -1) - { - j = BN_num_bits_word((BN_ULONG)bl); - } - j = 1<<(j-1); - assert(j <= al || j <= bl); - k = j+j; - t = BN_CTX_get(ctx); - if (t == NULL) - goto err; - if (al > j || bl > j) - { - if (bn_wexpand(t,k*4) == NULL) goto err; - if (bn_wexpand(rr,k*4) == NULL) goto err; - bn_mul_part_recursive(rr->d,a->d,b->d, - j,al-j,bl-j,t->d); - } - else /* al <= j || bl <= j */ - { - if (bn_wexpand(t,k*2) == NULL) goto err; - if (bn_wexpand(rr,k*2) == NULL) goto err; - bn_mul_recursive(rr->d,a->d,b->d, - j,al-j,bl-j,t->d); - } - rr->top=top; - goto end; - } -#if 0 - if (i == 1 && !BN_get_flags(b,BN_FLG_STATIC_DATA)) - { - BIGNUM *tmp_bn = (BIGNUM *)b; - if (bn_wexpand(tmp_bn,al) == NULL) goto err; - tmp_bn->d[bl]=0; - bl++; - i--; - } - else if (i == -1 && !BN_get_flags(a,BN_FLG_STATIC_DATA)) - { - BIGNUM *tmp_bn = (BIGNUM *)a; - if (bn_wexpand(tmp_bn,bl) == NULL) goto err; - tmp_bn->d[al]=0; - al++; - i++; - } - if (i == 0) - { - /* symmetric and > 4 */ - /* 16 or larger */ - j=BN_num_bits_word((BN_ULONG)al); - j=1<<(j-1); - k=j+j; - t = BN_CTX_get(ctx); - if (al == j) /* exact multiple */ - { - if (bn_wexpand(t,k*2) == NULL) goto err; - if (bn_wexpand(rr,k*2) == NULL) goto err; - bn_mul_recursive(rr->d,a->d,b->d,al,t->d); - } - else - { - if (bn_wexpand(t,k*4) == NULL) goto err; - if (bn_wexpand(rr,k*4) == NULL) goto err; - bn_mul_part_recursive(rr->d,a->d,b->d,al-j,j,t->d); - } - rr->top=top; - goto end; - } -#endif - } -#endif /* BN_RECURSION */ - if (bn_wexpand(rr,top) == NULL) goto err; - rr->top=top; - bn_mul_normal(rr->d,a->d,al,b->d,bl); + if ((al >= BN_MULL_SIZE_NORMAL) && (bl >= BN_MULL_SIZE_NORMAL)) { + if (i >= -1 && i <= 1) { + /* + * Find out the power of two lower or equal to the longest of the + * two numbers + */ + if (i >= 0) { + j = BN_num_bits_word((BN_ULONG)al); + } + if (i == -1) { + j = BN_num_bits_word((BN_ULONG)bl); + } + j = 1 << (j - 1); + assert(j <= al || j <= bl); + k = j + j; + t = BN_CTX_get(ctx); + if (t == NULL) + goto err; + if (al > j || bl > j) { + if (bn_wexpand(t, k * 4) == NULL) + goto err; + if (bn_wexpand(rr, k * 4) == NULL) + goto err; + bn_mul_part_recursive(rr->d, a->d, b->d, + j, al - j, bl - j, t->d); + } else { /* al <= j || bl <= j */ + + if (bn_wexpand(t, k * 2) == NULL) + goto err; + if (bn_wexpand(rr, k * 2) == NULL) + goto err; + bn_mul_recursive(rr->d, a->d, b->d, j, al - j, bl - j, t->d); + } + rr->top = top; + goto end; + } +# if 0 + if (i == 1 && !BN_get_flags(b, BN_FLG_STATIC_DATA)) { + BIGNUM *tmp_bn = (BIGNUM *)b; + if (bn_wexpand(tmp_bn, al) == NULL) + goto err; + tmp_bn->d[bl] = 0; + bl++; + i--; + } else if (i == -1 && !BN_get_flags(a, BN_FLG_STATIC_DATA)) { + BIGNUM *tmp_bn = (BIGNUM *)a; + if (bn_wexpand(tmp_bn, bl) == NULL) + goto err; + tmp_bn->d[al] = 0; + al++; + i++; + } + if (i == 0) { + /* symmetric and > 4 */ + /* 16 or larger */ + j = BN_num_bits_word((BN_ULONG)al); + j = 1 << (j - 1); + k = j + j; + t = BN_CTX_get(ctx); + if (al == j) { /* exact multiple */ + if (bn_wexpand(t, k * 2) == NULL) + goto err; + if (bn_wexpand(rr, k * 2) == NULL) + goto err; + bn_mul_recursive(rr->d, a->d, b->d, al, t->d); + } else { + if (bn_wexpand(t, k * 4) == NULL) + goto err; + if (bn_wexpand(rr, k * 4) == NULL) + goto err; + bn_mul_part_recursive(rr->d, a->d, b->d, al - j, j, t->d); + } + rr->top = top; + goto end; + } +# endif + } +#endif /* BN_RECURSION */ + if (bn_wexpand(rr, top) == NULL) + goto err; + rr->top = top; + bn_mul_normal(rr->d, a->d, al, b->d, bl); #if defined(BN_MUL_COMBA) || defined(BN_RECURSION) -end: + end: #endif - bn_correct_top(rr); - if (r != rr) BN_copy(r,rr); - ret=1; -err: - bn_check_top(r); - BN_CTX_end(ctx); - return(ret); - } + bn_correct_top(rr); + if (r != rr) + BN_copy(r, rr); + ret = 1; + err: + bn_check_top(r); + BN_CTX_end(ctx); + return (ret); +} void bn_mul_normal(BN_ULONG *r, BN_ULONG *a, int na, BN_ULONG *b, int nb) - { - BN_ULONG *rr; +{ + BN_ULONG *rr; #ifdef BN_COUNT - fprintf(stderr," bn_mul_normal %d * %d\n",na,nb); + fprintf(stderr, " bn_mul_normal %d * %d\n", na, nb); #endif - if (na < nb) - { - int itmp; - BN_ULONG *ltmp; - - itmp=na; na=nb; nb=itmp; - ltmp=a; a=b; b=ltmp; - - } - rr= &(r[na]); - if (nb <= 0) - { - (void)bn_mul_words(r,a,na,0); - return; - } - else - rr[0]=bn_mul_words(r,a,na,b[0]); - - for (;;) - { - if (--nb <= 0) return; - rr[1]=bn_mul_add_words(&(r[1]),a,na,b[1]); - if (--nb <= 0) return; - rr[2]=bn_mul_add_words(&(r[2]),a,na,b[2]); - if (--nb <= 0) return; - rr[3]=bn_mul_add_words(&(r[3]),a,na,b[3]); - if (--nb <= 0) return; - rr[4]=bn_mul_add_words(&(r[4]),a,na,b[4]); - rr+=4; - r+=4; - b+=4; - } - } + if (na < nb) { + int itmp; + BN_ULONG *ltmp; + + itmp = na; + na = nb; + nb = itmp; + ltmp = a; + a = b; + b = ltmp; + + } + rr = &(r[na]); + if (nb <= 0) { + (void)bn_mul_words(r, a, na, 0); + return; + } else + rr[0] = bn_mul_words(r, a, na, b[0]); + + for (;;) { + if (--nb <= 0) + return; + rr[1] = bn_mul_add_words(&(r[1]), a, na, b[1]); + if (--nb <= 0) + return; + rr[2] = bn_mul_add_words(&(r[2]), a, na, b[2]); + if (--nb <= 0) + return; + rr[3] = bn_mul_add_words(&(r[3]), a, na, b[3]); + if (--nb <= 0) + return; + rr[4] = bn_mul_add_words(&(r[4]), a, na, b[4]); + rr += 4; + r += 4; + b += 4; + } +} void bn_mul_low_normal(BN_ULONG *r, BN_ULONG *a, BN_ULONG *b, int n) - { +{ #ifdef BN_COUNT - fprintf(stderr," bn_mul_low_normal %d * %d\n",n,n); + fprintf(stderr, " bn_mul_low_normal %d * %d\n", n, n); #endif - bn_mul_words(r,a,n,b[0]); - - for (;;) - { - if (--n <= 0) return; - bn_mul_add_words(&(r[1]),a,n,b[1]); - if (--n <= 0) return; - bn_mul_add_words(&(r[2]),a,n,b[2]); - if (--n <= 0) return; - bn_mul_add_words(&(r[3]),a,n,b[3]); - if (--n <= 0) return; - bn_mul_add_words(&(r[4]),a,n,b[4]); - r+=4; - b+=4; - } - } + bn_mul_words(r, a, n, b[0]); + + for (;;) { + if (--n <= 0) + return; + bn_mul_add_words(&(r[1]), a, n, b[1]); + if (--n <= 0) + return; + bn_mul_add_words(&(r[2]), a, n, b[2]); + if (--n <= 0) + return; + bn_mul_add_words(&(r[3]), a, n, b[3]); + if (--n <= 0) + return; + bn_mul_add_words(&(r[4]), a, n, b[4]); + r += 4; + b += 4; + } +} |