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Diffstat (limited to 'src/lib/libcrypto/bn/bn_shift.c')
| -rw-r--r-- | src/lib/libcrypto/bn/bn_shift.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/src/lib/libcrypto/bn/bn_shift.c b/src/lib/libcrypto/bn/bn_shift.c new file mode 100644 index 0000000000..70f785ea18 --- /dev/null +++ b/src/lib/libcrypto/bn/bn_shift.c | |||
| @@ -0,0 +1,205 @@ | |||
| 1 | /* crypto/bn/bn_shift.c */ | ||
| 2 | /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) | ||
| 3 | * All rights reserved. | ||
| 4 | * | ||
| 5 | * This package is an SSL implementation written | ||
| 6 | * by Eric Young (eay@cryptsoft.com). | ||
| 7 | * The implementation was written so as to conform with Netscapes SSL. | ||
| 8 | * | ||
| 9 | * This library is free for commercial and non-commercial use as long as | ||
| 10 | * the following conditions are aheared to. The following conditions | ||
| 11 | * apply to all code found in this distribution, be it the RC4, RSA, | ||
| 12 | * lhash, DES, etc., code; not just the SSL code. The SSL documentation | ||
| 13 | * included with this distribution is covered by the same copyright terms | ||
| 14 | * except that the holder is Tim Hudson (tjh@cryptsoft.com). | ||
| 15 | * | ||
| 16 | * Copyright remains Eric Young's, and as such any Copyright notices in | ||
| 17 | * the code are not to be removed. | ||
| 18 | * If this package is used in a product, Eric Young should be given attribution | ||
| 19 | * as the author of the parts of the library used. | ||
| 20 | * This can be in the form of a textual message at program startup or | ||
| 21 | * in documentation (online or textual) provided with the package. | ||
| 22 | * | ||
| 23 | * Redistribution and use in source and binary forms, with or without | ||
| 24 | * modification, are permitted provided that the following conditions | ||
| 25 | * are met: | ||
| 26 | * 1. Redistributions of source code must retain the copyright | ||
| 27 | * notice, this list of conditions and the following disclaimer. | ||
| 28 | * 2. Redistributions in binary form must reproduce the above copyright | ||
| 29 | * notice, this list of conditions and the following disclaimer in the | ||
| 30 | * documentation and/or other materials provided with the distribution. | ||
| 31 | * 3. All advertising materials mentioning features or use of this software | ||
| 32 | * must display the following acknowledgement: | ||
| 33 | * "This product includes cryptographic software written by | ||
| 34 | * Eric Young (eay@cryptsoft.com)" | ||
| 35 | * The word 'cryptographic' can be left out if the rouines from the library | ||
| 36 | * being used are not cryptographic related :-). | ||
| 37 | * 4. If you include any Windows specific code (or a derivative thereof) from | ||
| 38 | * the apps directory (application code) you must include an acknowledgement: | ||
| 39 | * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" | ||
| 40 | * | ||
| 41 | * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND | ||
| 42 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
| 43 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | ||
| 44 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE | ||
| 45 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | ||
| 46 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | ||
| 47 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | ||
| 48 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | ||
| 49 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | ||
| 50 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | ||
| 51 | * SUCH DAMAGE. | ||
| 52 | * | ||
| 53 | * The licence and distribution terms for any publically available version or | ||
| 54 | * derivative of this code cannot be changed. i.e. this code cannot simply be | ||
| 55 | * copied and put under another distribution licence | ||
| 56 | * [including the GNU Public Licence.] | ||
| 57 | */ | ||
| 58 | |||
| 59 | #include <stdio.h> | ||
| 60 | #include "cryptlib.h" | ||
| 61 | #include "bn_lcl.h" | ||
| 62 | |||
| 63 | int BN_lshift1(BIGNUM *r, const BIGNUM *a) | ||
| 64 | { | ||
| 65 | register BN_ULONG *ap,*rp,t,c; | ||
| 66 | int i; | ||
| 67 | |||
| 68 | if (r != a) | ||
| 69 | { | ||
| 70 | r->neg=a->neg; | ||
| 71 | if (bn_wexpand(r,a->top+1) == NULL) return(0); | ||
| 72 | r->top=a->top; | ||
| 73 | } | ||
| 74 | else | ||
| 75 | { | ||
| 76 | if (bn_wexpand(r,a->top+1) == NULL) return(0); | ||
| 77 | } | ||
| 78 | ap=a->d; | ||
| 79 | rp=r->d; | ||
| 80 | c=0; | ||
| 81 | for (i=0; i<a->top; i++) | ||
| 82 | { | ||
| 83 | t= *(ap++); | ||
| 84 | *(rp++)=((t<<1)|c)&BN_MASK2; | ||
| 85 | c=(t & BN_TBIT)?1:0; | ||
| 86 | } | ||
| 87 | if (c) | ||
| 88 | { | ||
| 89 | *rp=1; | ||
| 90 | r->top++; | ||
| 91 | } | ||
| 92 | return(1); | ||
| 93 | } | ||
| 94 | |||
| 95 | int BN_rshift1(BIGNUM *r, const BIGNUM *a) | ||
| 96 | { | ||
| 97 | BN_ULONG *ap,*rp,t,c; | ||
| 98 | int i; | ||
| 99 | |||
| 100 | if (BN_is_zero(a)) | ||
| 101 | { | ||
| 102 | BN_zero(r); | ||
| 103 | return(1); | ||
| 104 | } | ||
| 105 | if (a != r) | ||
| 106 | { | ||
| 107 | if (bn_wexpand(r,a->top) == NULL) return(0); | ||
| 108 | r->top=a->top; | ||
| 109 | r->neg=a->neg; | ||
| 110 | } | ||
| 111 | ap=a->d; | ||
| 112 | rp=r->d; | ||
| 113 | c=0; | ||
| 114 | for (i=a->top-1; i>=0; i--) | ||
| 115 | { | ||
| 116 | t=ap[i]; | ||
| 117 | rp[i]=((t>>1)&BN_MASK2)|c; | ||
| 118 | c=(t&1)?BN_TBIT:0; | ||
| 119 | } | ||
| 120 | bn_fix_top(r); | ||
| 121 | return(1); | ||
| 122 | } | ||
| 123 | |||
| 124 | int BN_lshift(BIGNUM *r, const BIGNUM *a, int n) | ||
| 125 | { | ||
| 126 | int i,nw,lb,rb; | ||
| 127 | BN_ULONG *t,*f; | ||
| 128 | BN_ULONG l; | ||
| 129 | |||
| 130 | r->neg=a->neg; | ||
| 131 | nw=n/BN_BITS2; | ||
| 132 | if (bn_wexpand(r,a->top+nw+1) == NULL) return(0); | ||
| 133 | lb=n%BN_BITS2; | ||
| 134 | rb=BN_BITS2-lb; | ||
| 135 | f=a->d; | ||
| 136 | t=r->d; | ||
| 137 | t[a->top+nw]=0; | ||
| 138 | if (lb == 0) | ||
| 139 | for (i=a->top-1; i>=0; i--) | ||
| 140 | t[nw+i]=f[i]; | ||
| 141 | else | ||
| 142 | for (i=a->top-1; i>=0; i--) | ||
| 143 | { | ||
| 144 | l=f[i]; | ||
| 145 | t[nw+i+1]|=(l>>rb)&BN_MASK2; | ||
| 146 | t[nw+i]=(l<<lb)&BN_MASK2; | ||
| 147 | } | ||
| 148 | memset(t,0,nw*sizeof(t[0])); | ||
| 149 | /* for (i=0; i<nw; i++) | ||
| 150 | t[i]=0;*/ | ||
| 151 | r->top=a->top+nw+1; | ||
| 152 | bn_fix_top(r); | ||
| 153 | return(1); | ||
| 154 | } | ||
| 155 | |||
| 156 | int BN_rshift(BIGNUM *r, const BIGNUM *a, int n) | ||
| 157 | { | ||
| 158 | int i,j,nw,lb,rb; | ||
| 159 | BN_ULONG *t,*f; | ||
| 160 | BN_ULONG l,tmp; | ||
| 161 | |||
| 162 | nw=n/BN_BITS2; | ||
| 163 | rb=n%BN_BITS2; | ||
| 164 | lb=BN_BITS2-rb; | ||
| 165 | if (nw > a->top || a->top == 0) | ||
| 166 | { | ||
| 167 | BN_zero(r); | ||
| 168 | return(1); | ||
| 169 | } | ||
| 170 | if (r != a) | ||
| 171 | { | ||
| 172 | r->neg=a->neg; | ||
| 173 | if (bn_wexpand(r,a->top-nw+1) == NULL) return(0); | ||
| 174 | } | ||
| 175 | else | ||
| 176 | { | ||
| 177 | if (n == 0) | ||
| 178 | return 1; /* or the copying loop will go berserk */ | ||
| 179 | } | ||
| 180 | |||
| 181 | f= &(a->d[nw]); | ||
| 182 | t=r->d; | ||
| 183 | j=a->top-nw; | ||
| 184 | r->top=j; | ||
| 185 | |||
| 186 | if (rb == 0) | ||
| 187 | { | ||
| 188 | for (i=j+1; i > 0; i--) | ||
| 189 | *(t++)= *(f++); | ||
| 190 | } | ||
| 191 | else | ||
| 192 | { | ||
| 193 | l= *(f++); | ||
| 194 | for (i=1; i<j; i++) | ||
| 195 | { | ||
| 196 | tmp =(l>>rb)&BN_MASK2; | ||
| 197 | l= *(f++); | ||
| 198 | *(t++) =(tmp|(l<<lb))&BN_MASK2; | ||
| 199 | } | ||
| 200 | *(t++) =(l>>rb)&BN_MASK2; | ||
| 201 | } | ||
| 202 | *t=0; | ||
| 203 | bn_fix_top(r); | ||
| 204 | return(1); | ||
| 205 | } | ||
