Source/lib/crypto/hashers/sha1_hasher.c

   1 /**
   2  * @file sha1_hasher.c
   3  *
   4  * @brief Implementation of hasher_sha_t.
   5  *
   6  */
   7
   8 /*
   9  * Copyright (C) 2005 Jan Hutter, Martin Willi
  10  * Hochschule fuer Technik Rapperswil
  11  *
  12  * Ported from Steve Reid's <steve@edmweb.com> implementation
  13  * "SHA1 in C" found in strongSwan.
  14  *
  15  * This program is free software; you can redistribute it and/or modify it
  16  * under the terms of the GNU General Public License as published by the
  17  * Free Software Foundation; either version 2 of the License, or (at your
  18  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  19  *
  20  * This program is distributed in the hope that it will be useful, but
  21  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  22  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  23  * for more details.
  24  */
  25
  26 #include <string.h>
  27
  28 #include "sha1_hasher.h"
  29
  30 #include <definitions.h>
  31
  32 #define BLOCK_SIZE_SHA1 20
  33
  34 /*
  35  * ugly macro stuff
  36  */
  37 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
  38
  39 #if BYTE_ORDER == LITTLE_ENDIAN
  40  #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) |(rol(block->l[i],8)&0x00FF00FF))
  41 #elif BYTE_ORDER == BIG_ENDIAN
  42  #define blk0(i) block->l[i]
  43 #else
  44  #error "Endianness not defined!"
  45 #endif
  46 #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))
  47
  48 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
  49 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
  50 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
  51 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
  52 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
  53 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
  54
  55
  56 typedef struct private_sha1_hasher_t private_sha1_hasher_t;
  57
  58 /**
  59  * Private data structure with hasing context.
  60  */
  61 struct private_sha1_hasher_t {
  62         /**
  63          * Public interface for this hasher.
  64          */
  65         sha1_hasher_t public;
  66
  67         /*
  68          * State of the hasher.
  69          */
  70         u_int32_t state[5];
  71     u_int32_t count[2];
  72     u_int8_t buffer[64];
  73 };
  74
  75 /*
  76  * Hash a single 512-bit block. This is the core of the algorithm. *
  77  */
  78 static void SHA1Transform(u_int32_t state[5], const unsigned char buffer[64])
  79 {
  80         u_int32_t a, b, c, d, e;
  81         typedef union {
  82         u_int8_t c[64];
  83         u_int32_t l[16];
  84         } CHAR64LONG16;
  85         CHAR64LONG16 block[1];  /* use array to appear as a pointer */
  86     memcpy(block, buffer, 64);
  87
  88     /* Copy context->state[] to working vars */
  89     a = state[0];
  90     b = state[1];
  91     c = state[2];
  92     d = state[3];
  93     e = state[4];
  94     /* 4 rounds of 20 operations each. Loop unrolled. */
  95     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);
  96     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);
  97     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);
  98     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);
  99     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);
 100     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);
 101     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);
 102     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);
 103     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);
 104     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);
 105     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);
 106     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);
 107     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);
 108     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);
 109     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);
 110     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);
 111     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);
 112     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);
 113     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);
 114     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);
 115     /* Add the working vars back into context.state[] */
 116     state[0] += a;
 117     state[1] += b;
 118     state[2] += c;
 119     state[3] += d;
 120     state[4] += e;
 121     /* Wipe variables */
 122     a = b = c = d = e = 0;
 123     memset(block, '\0', sizeof(block));
 124 }
 125
 126 /*
 127  * Run your data through this.
 128  */
 129 static void SHA1Update(private_sha1_hasher_t* this, u_int8_t *data, u_int32_t len)
 130 {
 131         u_int32_t i;
 132         u_int32_t j;
 133
 134     j = this->count[0];
 135     if ((this->count[0] += len << 3) < j)
 136     {
 137                 this->count[1]++;
 138     }
 139     this->count[1] += (len>>29);
 140     j = (j >> 3) & 63;
 141     if ((j + len) > 63)
 142     {
 143         memcpy(&this->buffer[j], data, (i = 64-j));
 144         SHA1Transform(this->state, this->buffer);
 145         for ( ; i + 63 < len; i += 64)
 146         {
 147             SHA1Transform(this->state, &data[i]);
 148         }
 149         j = 0;
 150     }
 151     else
 152     {
 153         i = 0;
 154     }
 155     memcpy(&this->buffer[j], &data[i], len - i);
 156 }
 157
 158
 159 /*
 160  * Add padding and return the message digest.
 161  */
 162 static void SHA1Final(private_sha1_hasher_t *this, u_int8_t *digest)
 163 {
 164         u_int32_t i;
 165         u_int8_t finalcount[8];
 166         u_int8_t c;
 167
 168     for (i = 0; i < 8; i++)
 169     {
 170         finalcount[i] = (u_int8_t)((this->count[(i >= 4 ? 0 : 1)]
 171          >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
 172     }
 173     c = 0200;
 174     SHA1Update(this, &c, 1);
 175     while ((this->count[0] & 504) != 448)
 176     {
 177                 c = 0000;
 178         SHA1Update(this, &c, 1);
 179     }
 180     SHA1Update(this, finalcount, 8);  /* Should cause a SHA1Transform() */
 181     for (i = 0; i < 20; i++)
 182     {
 183         digest[i] = (u_int8_t)((this->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
 184     }
 185 }
 186
 187
 188 /**
 189  * Implementation of hasher_t.get_hash.
 190  */
 191 static void get_hash(private_sha1_hasher_t *this, chunk_t chunk, u_int8_t *buffer)
 192 {
 193         SHA1Update(this, chunk.ptr, chunk.len);
 194         if (buffer != NULL)
 195         {
 196                 SHA1Final(this, buffer);
 197                 this->public.hasher_interface.reset(&(this->public.hasher_interface));
 198         }
 199 }
 200
 201
 202 /**
 203  * Implementation of hasher_t.allocate_hash.
 204  */
 205 static void allocate_hash(private_sha1_hasher_t *this, chunk_t chunk, chunk_t *hash)
 206 {
 207         chunk_t allocated_hash;
 208
 209         SHA1Update(this, chunk.ptr, chunk.len);
 210         if (hash != NULL)
 211         {
 212                 allocated_hash.ptr = malloc(BLOCK_SIZE_SHA1);
 213                 allocated_hash.len = BLOCK_SIZE_SHA1;
 214
 215                 SHA1Final(this, allocated_hash.ptr);
 216                 this->public.hasher_interface.reset(&(this->public.hasher_interface));
 217
 218                 *hash = allocated_hash;
 219         }
 220 }
 221
 222 /**
 223  * Implementation of hasher_t.get_hash_size.
 224  */
 225 static size_t get_hash_size(private_sha1_hasher_t *this)
 226 {
 227         return BLOCK_SIZE_SHA1;
 228 }
 229
 230 /**
 231  * Implementation of hasher_t.reset.
 232  */
 233 static void reset(private_sha1_hasher_t *this)
 234 {
 235         this->state[0] = 0x67452301;
 236     this->state[1] = 0xEFCDAB89;
 237     this->state[2] = 0x98BADCFE;
 238     this->state[3] = 0x10325476;
 239     this->state[4] = 0xC3D2E1F0;
 240     this->count[0] = 0;
 241     this->count[1] = 0;
 242 }
 243 /**
 244  * Implementation of hasher_t.destroy.
 245  */
 246 static void destroy(private_sha1_hasher_t *this)
 247 {
 248         free(this);
 249 }
 250
 251
 252 /*
 253  * Described in header.
 254  */
 255 sha1_hasher_t *sha1_hasher_create()
 256 {
 257         private_sha1_hasher_t *this = malloc_thing(private_sha1_hasher_t);
 258
 259         this->public.hasher_interface.get_hash = (void (*) (hasher_t*, chunk_t, u_int8_t*))get_hash;
 260         this->public.hasher_interface.allocate_hash = (void (*) (hasher_t*, chunk_t, chunk_t*))allocate_hash;
 261         this->public.hasher_interface.get_hash_size = (size_t (*) (hasher_t*))get_hash_size;
 262         this->public.hasher_interface.reset = (void (*) (hasher_t*))reset;
 263         this->public.hasher_interface.destroy = (void (*) (hasher_t*))destroy;
 264
 265         /* initialize */
 266         this->public.hasher_interface.reset(&(this->public.hasher_interface));
 267
 268         return &(this->public);
 269 }