apt-pkg/contrib/sha1.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: sha1.cc,v 1.3 2001/05/13 05:15:03 jgg Exp $
   4 /* ######################################################################
   5
   6    SHA1 - SHA-1 Secure Hash Algorithm.
   7
   8    This file is a Public Domain wrapper for the Public Domain SHA1
   9    calculation code that is at it's end.
  10
  11    The algorithm was originally implemented by
  12    Steve Reid <sreid@sea-to-sky.net> and later modified by
  13    James H. Brown <jbrown@burgoyne.com>.
  14
  15    Modifications for APT were done by Alfredo K. Kojima and Jason
  16    Gunthorpe.
  17
  18    Still in the public domain.
  19
  20    Test Vectors (from FIPS PUB 180-1)
  21    "abc"
  22    A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
  23    "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
  24    84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
  25    A million repetitions of "a"
  26    34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
  27
  28    #####################################################################
  29  */
  30                                                                         /*}}} */
  31 // Include Files                                                        /*{{{*/
  32 #include <config.h>
  33
  34 #include <apt-pkg/sha1.h>
  35
  36 #include <stdint.h>
  37 #include <string.h>
  38                                                                         /*}}}*/
  39
  40 // SHA1Transform - Alters an existing SHA-1 hash                        /*{{{*/
  41 // ---------------------------------------------------------------------
  42 /* The core of the SHA-1 algorithm. This alters an existing SHA-1 hash to
  43    reflect the addition of 16 longwords of new data. Other routines convert
  44    incoming stream data into 16 long word chunks for this routine */
  45
  46 #define rol(value,bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
  47
  48 /* blk0() and blk() perform the initial expand. */
  49 /* I got the idea of expanding during the round function from SSLeay */
  50 #ifndef WORDS_BIGENDIAN
  51 #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
  52     |(rol(block->l[i],8)&0x00FF00FF))
  53 #else
  54 #define blk0(i) block->l[i]
  55 #endif
  56 #define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
  57     ^block->l[(i+2)&15]^block->l[i&15],1))
  58
  59 /* (R0+R1),R2,R3,R4 are the different operations used in SHA1 */
  60 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
  61 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
  62 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
  63 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
  64 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
  65
  66 static void SHA1Transform(uint32_t state[5],uint8_t const buffer[64])
  67 {
  68    uint32_t a,b,c,d,e;
  69    typedef union
  70    {
  71       uint8_t c[64];
  72       uint32_t l[16];
  73    }
  74    CHAR64LONG16;
  75    CHAR64LONG16 workspace, *block;
  76
  77    block = &workspace;
  78    memcpy(block,buffer,sizeof(workspace));
  79
  80    /* Copy context->state[] to working vars */
  81    a = state[0];
  82    b = state[1];
  83    c = state[2];
  84    d = state[3];
  85    e = state[4];
  86
  87    /* 4 rounds of 20 operations each. Loop unrolled. */
  88    R0(a,b,c,d,e,0);
  89    R0(e,a,b,c,d,1);
  90    R0(d,e,a,b,c,2);
  91    R0(c,d,e,a,b,3);
  92    R0(b,c,d,e,a,4);
  93    R0(a,b,c,d,e,5);
  94    R0(e,a,b,c,d,6);
  95    R0(d,e,a,b,c,7);
  96    R0(c,d,e,a,b,8);
  97    R0(b,c,d,e,a,9);
  98    R0(a,b,c,d,e,10);
  99    R0(e,a,b,c,d,11);
 100    R0(d,e,a,b,c,12);
 101    R0(c,d,e,a,b,13);
 102    R0(b,c,d,e,a,14);
 103    R0(a,b,c,d,e,15);
 104    R1(e,a,b,c,d,16);
 105    R1(d,e,a,b,c,17);
 106    R1(c,d,e,a,b,18);
 107    R1(b,c,d,e,a,19);
 108    R2(a,b,c,d,e,20);
 109    R2(e,a,b,c,d,21);
 110    R2(d,e,a,b,c,22);
 111    R2(c,d,e,a,b,23);
 112    R2(b,c,d,e,a,24);
 113    R2(a,b,c,d,e,25);
 114    R2(e,a,b,c,d,26);
 115    R2(d,e,a,b,c,27);
 116    R2(c,d,e,a,b,28);
 117    R2(b,c,d,e,a,29);
 118    R2(a,b,c,d,e,30);
 119    R2(e,a,b,c,d,31);
 120    R2(d,e,a,b,c,32);
 121    R2(c,d,e,a,b,33);
 122    R2(b,c,d,e,a,34);
 123    R2(a,b,c,d,e,35);
 124    R2(e,a,b,c,d,36);
 125    R2(d,e,a,b,c,37);
 126    R2(c,d,e,a,b,38);
 127    R2(b,c,d,e,a,39);
 128    R3(a,b,c,d,e,40);
 129    R3(e,a,b,c,d,41);
 130    R3(d,e,a,b,c,42);
 131    R3(c,d,e,a,b,43);
 132    R3(b,c,d,e,a,44);
 133    R3(a,b,c,d,e,45);
 134    R3(e,a,b,c,d,46);
 135    R3(d,e,a,b,c,47);
 136    R3(c,d,e,a,b,48);
 137    R3(b,c,d,e,a,49);
 138    R3(a,b,c,d,e,50);
 139    R3(e,a,b,c,d,51);
 140    R3(d,e,a,b,c,52);
 141    R3(c,d,e,a,b,53);
 142    R3(b,c,d,e,a,54);
 143    R3(a,b,c,d,e,55);
 144    R3(e,a,b,c,d,56);
 145    R3(d,e,a,b,c,57);
 146    R3(c,d,e,a,b,58);
 147    R3(b,c,d,e,a,59);
 148    R4(a,b,c,d,e,60);
 149    R4(e,a,b,c,d,61);
 150    R4(d,e,a,b,c,62);
 151    R4(c,d,e,a,b,63);
 152    R4(b,c,d,e,a,64);
 153    R4(a,b,c,d,e,65);
 154    R4(e,a,b,c,d,66);
 155    R4(d,e,a,b,c,67);
 156    R4(c,d,e,a,b,68);
 157    R4(b,c,d,e,a,69);
 158    R4(a,b,c,d,e,70);
 159    R4(e,a,b,c,d,71);
 160    R4(d,e,a,b,c,72);
 161    R4(c,d,e,a,b,73);
 162    R4(b,c,d,e,a,74);
 163    R4(a,b,c,d,e,75);
 164    R4(e,a,b,c,d,76);
 165    R4(d,e,a,b,c,77);
 166    R4(c,d,e,a,b,78);
 167    R4(b,c,d,e,a,79);
 168
 169    /* Add the working vars back into context.state[] */
 170    state[0] += a;
 171    state[1] += b;
 172    state[2] += c;
 173    state[3] += d;
 174    state[4] += e;
 175 }
 176                                                                         /*}}}*/
 177
 178 // SHA1Summation::SHA1Summation - Constructor                           /*{{{*/
 179 // ---------------------------------------------------------------------
 180 /* */
 181 SHA1Summation::SHA1Summation()
 182 {
 183    uint32_t *state = (uint32_t *)State;
 184    uint32_t *count = (uint32_t *)Count;
 185
 186    /* SHA1 initialization constants */
 187    state[0] = 0x67452301;
 188    state[1] = 0xEFCDAB89;
 189    state[2] = 0x98BADCFE;
 190    state[3] = 0x10325476;
 191    state[4] = 0xC3D2E1F0;
 192    count[0] = 0;
 193    count[1] = 0;
 194    Done = false;
 195 }
 196                                                                         /*}}}*/
 197 // SHA1Summation::Result - Return checksum value                        /*{{{*/
 198 // ---------------------------------------------------------------------
 199 /* Add() may not be called after this */
 200 SHA1SumValue SHA1Summation::Result()
 201 {
 202    uint32_t *state = (uint32_t *)State;
 203    uint32_t *count = (uint32_t *)Count;
 204
 205    // Apply the padding
 206    if (Done == false)
 207    {
 208       unsigned char finalcount[8];
 209
 210       for (unsigned i = 0; i < 8; i++)
 211       {
 212          // Endian independent
 213          finalcount[i] = (unsigned char) ((count[(i >= 4 ? 0 : 1)]
 214                                            >> ((3 - (i & 3)) * 8)) & 255);
 215       }
 216
 217       Add((unsigned char *) "\200",1);
 218       while ((count[0] & 504) != 448)
 219          Add((unsigned char *) "\0",1);
 220
 221       Add(finalcount,8);        /* Should cause a SHA1Transform() */
 222
 223    }
 224
 225    Done = true;
 226
 227    // Transfer over the result
 228    SHA1SumValue Value;
 229    unsigned char res[20];
 230    for (unsigned i = 0; i < 20; i++)
 231    {
 232       res[i] = (unsigned char)
 233          ((state[i >> 2] >> ((3 - (i & 3)) * 8)) & 255);
 234    }
 235    Value.Set(res);
 236    return Value;
 237 }
 238                                                                         /*}}}*/
 239 // SHA1Summation::Add - Adds content of buffer into the checksum        /*{{{*/
 240 // ---------------------------------------------------------------------
 241 /* May not be called after Result() is called */
 242 bool SHA1Summation::Add(const unsigned char *data,unsigned long long len)
 243 {
 244    if (Done)
 245       return false;
 246    if (len == 0)
 247       return true;
 248
 249    uint32_t *state = (uint32_t *)State;
 250    uint32_t *count = (uint32_t *)Count;
 251    uint8_t *buffer = (uint8_t *)Buffer;
 252    uint32_t i,j;
 253
 254    j = (count[0] >> 3) & 63;
 255    if ((count[0] += len << 3) < (len << 3))
 256       count[1]++;
 257    count[1] += (len >> 29);
 258    if ((j + len) > 63)
 259    {
 260       memcpy(&buffer[j],data,(i = 64 - j));
 261       SHA1Transform(state,buffer);
 262       for (; i + 63 < len; i += 64)
 263       {
 264          SHA1Transform(state,&data[i]);
 265       }
 266       j = 0;
 267    }
 268    else
 269       i = 0;
 270    memcpy(&buffer[j],&data[i],len - i);
 271
 272    return true;
 273 }
 274                                                                         /*}}}*/