src/libstrongswan/plugins/sha1/sha1_hasher.c

   1 /*
   2  * Copyright (C) 2005-2006 Martin Willi
   3  * Copyright (C) 2005 Jan Hutter
   4  * HSR Hochschule fuer Technik Rapperswil
   5  *
   6  * Ported from Steve Reid's <steve@edmweb.com> implementation
   7  * "SHA1 in C" found in strongSwan.
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License as published by the
  11  * Free Software Foundation; either version 2 of the License, or (at your
  12  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  16  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17  * for more details.
  18  */
  19
  20 #include <string.h>
  21
  22 #include <library.h>
  23
  24 #include "sha1_hasher.h"
  25
  26 /*
  27  * ugly macro stuff
  28  */
  29 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
  30
  31 #if BYTE_ORDER == LITTLE_ENDIAN
  32  #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) |(rol(block->l[i],8)&0x00FF00FF))
  33 #elif BYTE_ORDER == BIG_ENDIAN
  34  #define blk0(i) block->l[i]
  35 #else
  36  #error "Endianness not defined!"
  37 #endif
  38 #define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] ^block->l[(i+2)&15]^block->l[i&15],1))
  39
  40 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
  41 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
  42 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
  43 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
  44 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
  45 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
  46
  47
  48 typedef struct private_sha1_hasher_t private_sha1_hasher_t;
  49
  50 /**
  51  * Private data structure with hashing context.
  52  */
  53 struct private_sha1_hasher_t {
  54         /**
  55          * Public interface for this hasher.
  56          */
  57         sha1_hasher_t public;
  58
  59         /*
  60          * State of the hasher. Shared with sha1_prf.c, do not change it!!!
  61          */
  62         uint32_t state[5];
  63         uint32_t count[2];
  64         uint8_t buffer[64];
  65 };
  66
  67 /*
  68  * Hash a single 512-bit block. This is the core of the algorithm. *
  69  */
  70 static void SHA1Transform(uint32_t state[5], const unsigned char buffer[64])
  71 {
  72         uint32_t a, b, c, d, e;
  73         typedef union {
  74                 uint8_t c[64];
  75                 uint32_t l[16];
  76         } CHAR64LONG16;
  77         CHAR64LONG16 block[1];  /* use array to appear as a pointer */
  78         memcpy(block, buffer, 64);
  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         /* 4 rounds of 20 operations each. Loop unrolled. */
  87         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);
  88         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);
  89         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);
  90         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);
  91         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);
  92         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);
  93         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);
  94         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);
  95         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);
  96         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);
  97         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);
  98         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);
  99         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);
 100         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);
 101         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);
 102         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);
 103         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);
 104         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);
 105         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);
 106         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);
 107         /* Add the working vars back into context.state[] */
 108         state[0] += a;
 109         state[1] += b;
 110         state[2] += c;
 111         state[3] += d;
 112         state[4] += e;
 113         /* Wipe variables */
 114         a = b = c = d = e = 0;
 115         memset(block, '\0', sizeof(block));
 116 }
 117
 118 /**
 119  * Run your data through this. Also used in sha1_prf.
 120  */
 121 void SHA1Update(private_sha1_hasher_t* this, uint8_t *data, uint32_t len)
 122 {
 123         uint32_t i;
 124         uint32_t j;
 125
 126         j = this->count[0];
 127         if ((this->count[0] += len << 3) < j)
 128         {
 129                 this->count[1]++;
 130         }
 131         this->count[1] += (len>>29);
 132         j = (j >> 3) & 63;
 133         if ((j + len) > 63)
 134         {
 135                 memcpy(&this->buffer[j], data, (i = 64-j));
 136                 SHA1Transform(this->state, this->buffer);
 137                 for ( ; i + 63 < len; i += 64)
 138                 {
 139                     SHA1Transform(this->state, &data[i]);
 140                 }
 141                 j = 0;
 142         }
 143         else
 144         {
 145                 i = 0;
 146         }
 147         memcpy(&this->buffer[j], &data[i], len - i);
 148 }
 149
 150
 151 /*
 152  * Add padding and return the message digest.
 153  */
 154 static void SHA1Final(private_sha1_hasher_t *this, uint8_t *digest)
 155 {
 156         uint32_t i;
 157         uint8_t finalcount[8];
 158         uint8_t c;
 159
 160         for (i = 0; i < 8; i++)
 161         {
 162                 finalcount[i] = (uint8_t)((this->count[(i >= 4 ? 0 : 1)]
 163                  >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
 164         }
 165         c = 0200;
 166         SHA1Update(this, &c, 1);
 167         while ((this->count[0] & 504) != 448)
 168         {
 169                 c = 0000;
 170                 SHA1Update(this, &c, 1);
 171         }
 172         SHA1Update(this, finalcount, 8);  /* Should cause a SHA1Transform() */
 173         for (i = 0; i < 20; i++)
 174         {
 175                 digest[i] = (uint8_t)((this->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
 176         }
 177 }
 178
 179 METHOD(hasher_t, reset, bool,
 180         private_sha1_hasher_t *this)
 181 {
 182         this->state[0] = 0x67452301;
 183         this->state[1] = 0xEFCDAB89;
 184         this->state[2] = 0x98BADCFE;
 185         this->state[3] = 0x10325476;
 186         this->state[4] = 0xC3D2E1F0;
 187         this->count[0] = 0;
 188         this->count[1] = 0;
 189
 190         return TRUE;
 191 }
 192
 193 METHOD(hasher_t, get_hash, bool,
 194         private_sha1_hasher_t *this, chunk_t chunk, uint8_t *buffer)
 195 {
 196         SHA1Update(this, chunk.ptr, chunk.len);
 197         if (buffer != NULL)
 198         {
 199                 SHA1Final(this, buffer);
 200                 reset(this);
 201         }
 202         return TRUE;
 203 }
 204
 205 METHOD(hasher_t, allocate_hash, bool,
 206         private_sha1_hasher_t *this, chunk_t chunk, chunk_t *hash)
 207 {
 208         SHA1Update(this, chunk.ptr, chunk.len);
 209         if (hash != NULL)
 210         {
 211                 hash->ptr = malloc(HASH_SIZE_SHA1);
 212                 hash->len = HASH_SIZE_SHA1;
 213
 214                 SHA1Final(this, hash->ptr);
 215                 reset(this);
 216         }
 217         return TRUE;
 218 }
 219
 220 METHOD(hasher_t, get_hash_size, size_t,
 221         private_sha1_hasher_t *this)
 222 {
 223         return HASH_SIZE_SHA1;
 224 }
 225
 226 METHOD(hasher_t, destroy, void,
 227         private_sha1_hasher_t *this)
 228 {
 229         free(this);
 230 }
 231
 232 /*
 233  * Described in header.
 234  */
 235 sha1_hasher_t *sha1_hasher_create(hash_algorithm_t algo)
 236 {
 237         private_sha1_hasher_t *this;
 238
 239         if (algo != HASH_SHA1)
 240         {
 241                 return NULL;
 242         }
 243
 244         INIT(this,
 245                 .public = {
 246                         .hasher_interface = {
 247                                 .get_hash = _get_hash,
 248                                 .allocate_hash = _allocate_hash,
 249                                 .get_hash_size = _get_hash_size,
 250                                 .reset = _reset,
 251                                 .destroy = _destroy,
 252                         },
 253                 },
 254         );
 255
 256         /* initialize */
 257         reset(this);
 258
 259         return &(this->public);
 260 }