sha1.c

   1 /*
   2  * The contents of this file are subject to the Mozilla Public
   3  * License Version 1.1 (the "License"); you may not use this file
   4  * except in compliance with the License. You may obtain a copy of
   5  * the License at http://www.mozilla.org/MPL/
   6  *
   7  * Software distributed under the License is distributed on an "AS
   8  * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
   9  * implied. See the License for the specific language governing
  10  * rights and limitations under the License.
  11  *
  12  * The Original Code is SHA 180-1 Reference Implementation (Compact version)
  13  *
  14  * The Initial Developer of the Original Code is Paul Kocher of
  15  * Cryptography Research.  Portions created by Paul Kocher are
  16  * Copyright (C) 1995-9 by Cryptography Research, Inc.  All
  17  * Rights Reserved.
  18  *
  19  * Contributor(s):
  20  *
  21  *     Paul Kocher
  22  *
  23  * Alternatively, the contents of this file may be used under the
  24  * terms of the GNU General Public License Version 2 or later (the
  25  * "GPL"), in which case the provisions of the GPL are applicable
  26  * instead of those above.  If you wish to allow use of your
  27  * version of this file only under the terms of the GPL and not to
  28  * allow others to use your version of this file under the MPL,
  29  * indicate your decision by deleting the provisions above and
  30  * replace them with the notice and other provisions required by
  31  * the GPL.  If you do not delete the provisions above, a recipient
  32  * may use your version of this file under either the MPL or the
  33  * GPL.
  34  */
  35
  36 #include "sha1.h"
  37
  38 static void shaHashBlock(SHA_CTX * ctx);
  39
  40 void SHA1_Init(SHA_CTX * ctx)
  41 {
  42     int i;
  43
  44     ctx->lenW = 0;
  45     ctx->sizeHi = ctx->sizeLo = 0;
  46
  47     /* Initialize H with the magic constants (see FIPS180 for constants)
  48      */
  49     ctx->H[0] = 0x67452301;
  50     ctx->H[1] = 0xefcdab89;
  51     ctx->H[2] = 0x98badcfe;
  52     ctx->H[3] = 0x10325476;
  53     ctx->H[4] = 0xc3d2e1f0;
  54
  55     for (i = 0; i < 80; i++)
  56         ctx->W[i] = 0;
  57 }
  58
  59
  60 void SHA1_Update(SHA_CTX * ctx, void *_dataIn, int len)
  61 {
  62     unsigned char *dataIn = _dataIn;
  63     int i;
  64
  65     /* Read the data into W and process blocks as they get full
  66      */
  67     for (i = 0; i < len; i++) {
  68         ctx->W[ctx->lenW / 4] <<= 8;
  69         ctx->W[ctx->lenW / 4] |= (unsigned int) dataIn[i];
  70         if ((++ctx->lenW) % 64 == 0) {
  71             shaHashBlock(ctx);
  72             ctx->lenW = 0;
  73         }
  74         ctx->sizeLo += 8;
  75         ctx->sizeHi += (ctx->sizeLo < 8);
  76     }
  77 }
  78
  79
  80 void SHA1_Final(unsigned char hashout[20], SHA_CTX * ctx)
  81 {
  82     unsigned char pad0x80 = 0x80;
  83     unsigned char pad0x00 = 0x00;
  84     unsigned char padlen[8];
  85     int i;
  86
  87     /* Pad with a binary 1 (e.g. 0x80), then zeroes, then length
  88      */
  89     padlen[0] = (unsigned char) ((ctx->sizeHi >> 24) & 255);
  90     padlen[1] = (unsigned char) ((ctx->sizeHi >> 16) & 255);
  91     padlen[2] = (unsigned char) ((ctx->sizeHi >> 8) & 255);
  92     padlen[3] = (unsigned char) ((ctx->sizeHi >> 0) & 255);
  93     padlen[4] = (unsigned char) ((ctx->sizeLo >> 24) & 255);
  94     padlen[5] = (unsigned char) ((ctx->sizeLo >> 16) & 255);
  95     padlen[6] = (unsigned char) ((ctx->sizeLo >> 8) & 255);
  96     padlen[7] = (unsigned char) ((ctx->sizeLo >> 0) & 255);
  97     SHA1_Update(ctx, &pad0x80, 1);
  98     while (ctx->lenW != 56)
  99         SHA1_Update(ctx, &pad0x00, 1);
 100     SHA1_Update(ctx, padlen, 8);
 101
 102     /* Output hash
 103      */
 104     for (i = 0; i < 20; i++) {
 105         hashout[i] = (unsigned char) (ctx->H[i / 4] >> 24);
 106         ctx->H[i / 4] <<= 8;
 107     }
 108
 109     /*
 110      *  Re-initialize the context (also zeroizes contents)
 111      */
 112     SHA1_Init(ctx);
 113 }
 114
 115
 116 #define SHA_ROT(X,n) (((X) << (n)) | ((X) >> (32-(n))))
 117
 118 static void shaHashBlock(SHA_CTX * ctx)
 119 {
 120     int t;
 121     unsigned int A, B, C, D, E, TEMP;
 122
 123     for (t = 16; t <= 79; t++)
 124         ctx->W[t] =
 125             SHA_ROT(ctx->W[t - 3] ^ ctx->W[t - 8] ^ ctx->
 126                     W[t - 14] ^ ctx->W[t - 16], 1);
 127
 128     A = ctx->H[0];
 129     B = ctx->H[1];
 130     C = ctx->H[2];
 131     D = ctx->H[3];
 132     E = ctx->H[4];
 133
 134     for (t = 0; t <= 19; t++) {
 135         TEMP =
 136             SHA_ROT(A,
 137                     5) + (((C ^ D) & B) ^ D) + E + ctx->W[t] + 0x5a827999;
 138         E = D;
 139         D = C;
 140         C = SHA_ROT(B, 30);
 141         B = A;
 142         A = TEMP;
 143     }
 144     for (t = 20; t <= 39; t++) {
 145         TEMP = SHA_ROT(A, 5) + (B ^ C ^ D) + E + ctx->W[t] + 0x6ed9eba1;
 146         E = D;
 147         D = C;
 148         C = SHA_ROT(B, 30);
 149         B = A;
 150         A = TEMP;
 151     }
 152     for (t = 40; t <= 59; t++) {
 153         TEMP =
 154             SHA_ROT(A,
 155                     5) + ((B & C) | (D & (B | C))) + E + ctx->W[t] +
 156             0x8f1bbcdc;
 157         E = D;
 158         D = C;
 159         C = SHA_ROT(B, 30);
 160         B = A;
 161         A = TEMP;
 162     }
 163     for (t = 60; t <= 79; t++) {
 164         TEMP = SHA_ROT(A, 5) + (B ^ C ^ D) + E + ctx->W[t] + 0xca62c1d6;
 165         E = D;
 166         D = C;
 167         C = SHA_ROT(B, 30);
 168         B = A;
 169         A = TEMP;
 170     }
 171
 172     ctx->H[0] += A;
 173     ctx->H[1] += B;
 174     ctx->H[2] += C;
 175     ctx->H[3] += D;
 176     ctx->H[4] += E;
 177 }