src/libstrongswan/plugins/sha1/sha1_hasher.c

   1 /*
   2  * Copyright (C) 2005-2006 Martin Willi
   3  * Copyright (C) 2005 Jan Hutter
   4  * 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 #include <arpa/inet.h>
  22
  23 #include "sha1_hasher.h"
  24
  25 /*
  26  * ugly macro stuff
  27  */
  28 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
  29
  30 #if BYTE_ORDER == LITTLE_ENDIAN
  31  #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) |(rol(block->l[i],8)&0x00FF00FF))
  32 #elif BYTE_ORDER == BIG_ENDIAN
  33  #define blk0(i) block->l[i]
  34 #else
  35  #error "Endianness not defined!"
  36 #endif
  37 #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))
  38
  39 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
  40 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
  41 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
  42 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
  43 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
  44 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
  45
  46
  47 typedef struct private_sha1_hasher_t private_sha1_hasher_t;
  48
  49 /**
  50  * Private data structure with hasing context.
  51  */
  52 struct private_sha1_hasher_t {
  53         /**
  54          * Public interface for this hasher.
  55          */
  56         sha1_hasher_t public;
  57
  58         /*
  59          * State of the hasher. Shared with sha1_prf.c, do not change it!!!
  60          */
  61         u_int32_t state[5];
  62         u_int32_t count[2];
  63         u_int8_t buffer[64];
  64 };
  65
  66 /*
  67  * Hash a single 512-bit block. This is the core of the algorithm. *
  68  */
  69 static void SHA1Transform(u_int32_t state[5], const unsigned char buffer[64])
  70 {
  71         u_int32_t a, b, c, d, e;
  72         typedef union {
  73                 u_int8_t c[64];
  74                 u_int32_t l[16];
  75         } CHAR64LONG16;
  76         CHAR64LONG16 block[1];  /* use array to appear as a pointer */
  77         memcpy(block, buffer, 64);
  78
  79         /* Copy context->state[] to working vars */
  80         a = state[0];
  81         b = state[1];
  82         c = state[2];
  83         d = state[3];
  84         e = state[4];
  85         /* 4 rounds of 20 operations each. Loop unrolled. */
  86         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);
  87         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);
  88         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);
  89         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);
  90         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);
  91         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);
  92         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);
  93         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);
  94         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);
  95         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);
  96         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);
  97         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);
  98         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);
  99         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);
 100         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);
 101         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);
 102         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);
 103         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);
 104         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);
 105         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);
 106         /* Add the working vars back into context.state[] */
 107         state[0] += a;
 108         state[1] += b;
 109         state[2] += c;
 110         state[3] += d;
 111         state[4] += e;
 112         /* Wipe variables */
 113         a = b = c = d = e = 0;
 114         memset(block, '\0', sizeof(block));
 115 }
 116
 117 /**
 118  * Run your data through this. Also used in sha1_prf.
 119  */
 120 void SHA1Update(private_sha1_hasher_t* this, u_int8_t *data, u_int32_t len)
 121 {
 122         u_int32_t i;
 123         u_int32_t j;
 124
 125         j = this->count[0];
 126         if ((this->count[0] += len << 3) < j)
 127         {
 128                 this->count[1]++;
 129         }
 130         this->count[1] += (len>>29);
 131         j = (j >> 3) & 63;
 132         if ((j + len) > 63)
 133         {
 134                 memcpy(&this->buffer[j], data, (i = 64-j));
 135                 SHA1Transform(this->state, this->buffer);
 136                 for ( ; i + 63 < len; i += 64)
 137                 {
 138                     SHA1Transform(this->state, &data[i]);
 139                 }
 140                 j = 0;
 141         }
 142         else
 143         {
 144                 i = 0;
 145         }
 146         memcpy(&this->buffer[j], &data[i], len - i);
 147 }
 148
 149
 150 /*
 151  * Add padding and return the message digest.
 152  */
 153 static void SHA1Final(private_sha1_hasher_t *this, u_int8_t *digest)
 154 {
 155         u_int32_t i;
 156         u_int8_t finalcount[8];
 157         u_int8_t c;
 158
 159         for (i = 0; i < 8; i++)
 160         {
 161                 finalcount[i] = (u_int8_t)((this->count[(i >= 4 ? 0 : 1)]
 162                  >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
 163         }
 164         c = 0200;
 165         SHA1Update(this, &c, 1);
 166         while ((this->count[0] & 504) != 448)
 167         {
 168                 c = 0000;
 169                 SHA1Update(this, &c, 1);
 170         }
 171         SHA1Update(this, finalcount, 8);  /* Should cause a SHA1Transform() */
 172         for (i = 0; i < 20; i++)
 173         {
 174                 digest[i] = (u_int8_t)((this->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
 175         }
 176 }
 177
 178 /**
 179  * Implementation of hasher_t.reset.
 180  */
 181 static void reset(private_sha1_hasher_t *this)
 182 {
 183         this->state[0] = 0x67452301;
 184         this->state[1] = 0xEFCDAB89;
 185         this->state[2] = 0x98BADCFE;
 186         this->state[3] = 0x10325476;
 187         this->state[4] = 0xC3D2E1F0;
 188         this->count[0] = 0;
 189         this->count[1] = 0;
 190 }
 191
 192 /**
 193  * Implementation of hasher_t.get_hash.
 194  */
 195 static void get_hash(private_sha1_hasher_t *this, chunk_t chunk, u_int8_t *buffer)
 196 {
 197         SHA1Update(this, chunk.ptr, chunk.len);
 198         if (buffer != NULL)
 199         {
 200                 SHA1Final(this, buffer);
 201                 reset(this);
 202         }
 203 }
 204
 205 /**
 206  * Implementation of hasher_t.allocate_hash.
 207  */
 208 static void allocate_hash(private_sha1_hasher_t *this, chunk_t chunk, chunk_t *hash)
 209 {
 210         SHA1Update(this, chunk.ptr, chunk.len);
 211         if (hash != NULL)
 212         {
 213                 hash->ptr = malloc(HASH_SIZE_SHA1);
 214                 hash->len = HASH_SIZE_SHA1;
 215
 216                 SHA1Final(this, hash->ptr);
 217                 reset(this);
 218         }
 219 }
 220
 221 /**
 222  * Implementation of hasher_t.get_hash_size.
 223  */
 224 static size_t get_hash_size(private_sha1_hasher_t *this)
 225 {
 226         return HASH_SIZE_SHA1;
 227 }
 228
 229 /**
 230  * Implementation of hasher_t.destroy.
 231  */
 232 static void destroy(private_sha1_hasher_t *this)
 233 {
 234         free(this);
 235 }
 236
 237 /*
 238  * Described in header.
 239  */
 240 sha1_hasher_t *sha1_hasher_create(hash_algorithm_t algo)
 241 {
 242         private_sha1_hasher_t *this;
 243         if (algo != HASH_SHA1)
 244         {
 245                 return NULL;
 246         }
 247         this = malloc_thing(private_sha1_hasher_t);
 248         this->public.hasher_interface.get_hash = (void (*) (hasher_t*, chunk_t, u_int8_t*))get_hash;
 249         this->public.hasher_interface.allocate_hash = (void (*) (hasher_t*, chunk_t, chunk_t*))allocate_hash;
 250         this->public.hasher_interface.get_hash_size = (size_t (*) (hasher_t*))get_hash_size;
 251         this->public.hasher_interface.reset = (void (*) (hasher_t*))reset;
 252         this->public.hasher_interface.destroy = (void (*) (hasher_t*))destroy;
 253
 254         /* initialize */
 255         reset(this);
 256
 257         return &(this->public);
 258 }
 259