keyanalyze/pgpring/sha1.c

   1 /*
   2  SHA-1 in C
   3
   4  By Steve Reid <steve@edmweb.com>, with small changes to make it
   5  fit into mutt by Thomas Roessler <roessler@does-not-exist.org>.
   6
   7  100% Public Domain.
   8
   9  Test Vectors (from FIPS PUB 180-1)
  10  "abc"
  11  A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
  12  "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
  13  84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
  14  A million repetitions of "a"
  15  34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
  16 */
  17
  18 #define SHA1HANDSOFF
  19
  20 #include <string.h>
  21
  22 #include "sha1.h"
  23
  24 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
  25
  26 /* blk0() and blk() perform the initial expand. */
  27 /* I got the idea of expanding during the round function from SSLeay */
  28 #ifdef WORDS_BIGENDIAN
  29 #  define blk0(i) block->l[i]
  30 #else
  31 #  define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
  32                     |(rol(block->l[i],8)&0x00FF00FF))
  33 #endif
  34
  35 #define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
  36     ^block->l[(i+2)&15]^block->l[i&15],1))
  37
  38 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
  39 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
  40 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
  41 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
  42 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
  43 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
  44
  45
  46 /* Hash a single 512-bit block. This is the core of the algorithm. */
  47
  48 void SHA1Transform(uint32_t state[5], const unsigned char buffer[64])
  49 {
  50 uint32_t a, b, c, d, e;
  51 typedef union {
  52     unsigned char c[64];
  53     uint32_t l[16];
  54 } CHAR64LONG16;
  55 #ifdef SHA1HANDSOFF
  56 CHAR64LONG16 block[1];  /* use array to appear as a pointer */
  57     memcpy(block, buffer, 64);
  58 #else
  59     /* The following had better never be used because it causes the
  60      * pointer-to-const buffer to be cast into a pointer to non-const.
  61      * And the result is written through.  I threw a "const" in, hoping
  62      * this will cause a diagnostic.
  63      */
  64 CHAR64LONG16* block = (const CHAR64LONG16*)buffer;
  65 #endif
  66     /* Copy context->state[] to working vars */
  67     a = state[0];
  68     b = state[1];
  69     c = state[2];
  70     d = state[3];
  71     e = state[4];
  72     /* 4 rounds of 20 operations each. Loop unrolled. */
  73     R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);
  74     R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);
  75     R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);
  76     R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);
  77     R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
  78     R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
  79     R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
  80     R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
  81     R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
  82     R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
  83     R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);
  84     R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
  85     R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
  86     R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
  87     R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
  88     R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
  89     R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
  90     R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
  91     R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
  92     R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);
  93     /* Add the working vars back into context.state[] */
  94     state[0] += a;
  95     state[1] += b;
  96     state[2] += c;
  97     state[3] += d;
  98     state[4] += e;
  99     /* Wipe variables */
 100     a = b = c = d = e = 0;
 101 #ifdef SHA1HANDSOFF
 102     memset(block, '\0', sizeof(block));
 103 #endif
 104 }
 105
 106
 107 /* SHA1Init - Initialize new context */
 108
 109 void SHA1Init(SHA1_CTX* context)
 110 {
 111     /* SHA1 initialization constants */
 112     context->state[0] = 0x67452301;
 113     context->state[1] = 0xEFCDAB89;
 114     context->state[2] = 0x98BADCFE;
 115     context->state[3] = 0x10325476;
 116     context->state[4] = 0xC3D2E1F0;
 117     context->count[0] = context->count[1] = 0;
 118 }
 119
 120
 121 /* Run your data through this. */
 122
 123 void SHA1Update(SHA1_CTX* context, const unsigned char* data, uint32_t len)
 124 {
 125 uint32_t i;
 126 uint32_t j;
 127
 128     j = context->count[0];
 129     if ((context->count[0] += len << 3) < j)
 130         context->count[1]++;
 131     context->count[1] += (len>>29);
 132     j = (j >> 3) & 63;
 133     if ((j + len) > 63) {
 134         memcpy(&context->buffer[j], data, (i = 64-j));
 135         SHA1Transform(context->state, context->buffer);
 136         for ( ; i + 63 < len; i += 64) {
 137             SHA1Transform(context->state, &data[i]);
 138         }
 139         j = 0;
 140     }
 141     else i = 0;
 142     memcpy(&context->buffer[j], &data[i], len - i);
 143 }
 144
 145
 146 /* Add padding and return the message digest. */
 147
 148 void SHA1Final(unsigned char digest[20], SHA1_CTX* context)
 149 {
 150 unsigned i;
 151 unsigned char finalcount[8];
 152 unsigned char c;
 153
 154 #if 0   /* untested "improvement" by DHR */
 155     /* Convert context->count to a sequence of bytes
 156      * in finalcount.  Second element first, but
 157      * big-endian order within element.
 158      * But we do it all backwards.
 159      */
 160     unsigned char *fcp = &finalcount[8];
 161
 162     for (i = 0; i < 2; i++)
 163     {
 164         uint32_t t = context->count[i];
 165         int j;
 166
 167         for (j = 0; j < 4; t >>= 8, j++)
 168             *--fcp = (unsigned char) t
 169     }
 170 #else
 171     for (i = 0; i < 8; i++) {
 172         finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)]
 173          >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
 174     }
 175 #endif
 176     c = 0200;
 177     SHA1Update(context, &c, 1);
 178     while ((context->count[0] & 504) != 448) {
 179         c = 0000;
 180         SHA1Update(context, &c, 1);
 181     }
 182     SHA1Update(context, finalcount, 8);  /* Should cause a SHA1Transform() */
 183     for (i = 0; i < 20; i++) {
 184         digest[i] = (unsigned char)
 185          ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
 186     }
 187     /* Wipe variables */
 188     memset(context, '\0', sizeof(*context));
 189     memset(&finalcount, '\0', sizeof(finalcount));
 190 }