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  * $Id$
  20  */
  21
  22 #include <string.h>
  23 #include <arpa/inet.h>
  24
  25 #include "sha1_hasher.h"
  26
  27 /*
  28  * ugly macro stuff
  29  */
  30 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
  31
  32 #if BYTE_ORDER == LITTLE_ENDIAN
  33  #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) |(rol(block->l[i],8)&0x00FF00FF))
  34 #elif BYTE_ORDER == BIG_ENDIAN
  35  #define blk0(i) block->l[i]
  36 #else
  37  #error "Endianness not defined!"
  38 #endif
  39 #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))
  40
  41 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
  42 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
  43 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
  44 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
  45 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
  46 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
  47
  48
  49 typedef struct private_sha1_hasher_t private_sha1_hasher_t;
  50
  51 /**
  52  * Private data structure with hasing context.
  53  */
  54 struct private_sha1_hasher_t {
  55         /**
  56          * Public interface for this hasher.
  57          */
  58         sha1_hasher_t public;
  59
  60         /*
  61          * State of the hasher. Shared with sha1_prf.c, do not change it!!!
  62          */
  63         u_int32_t state[5];
  64     u_int32_t count[2];
  65     u_int8_t buffer[64];
  66 };
  67
  68 /*
  69  * Hash a single 512-bit block. This is the core of the algorithm. *
  70  */
  71 static void SHA1Transform(u_int32_t state[5], const unsigned char buffer[64])
  72 {
  73         u_int32_t a, b, c, d, e;
  74         typedef union {
  75         u_int8_t c[64];
  76         u_int32_t l[16];
  77         } CHAR64LONG16;
  78         CHAR64LONG16 block[1];  /* use array to appear as a pointer */
  79     memcpy(block, buffer, 64);
  80
  81     /* Copy context->state[] to working vars */
  82     a = state[0];
  83     b = state[1];
  84     c = state[2];
  85     d = state[3];
  86     e = state[4];
  87     /* 4 rounds of 20 operations each. Loop unrolled. */
  88     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);
  89     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);
  90     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);
  91     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);
  92     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);
  93     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);
  94     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);
  95     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);
  96     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);
  97     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);
  98     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);
  99     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);
 100     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);
 101     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);
 102     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);
 103     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);
 104     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);
 105     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);
 106     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);
 107     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);
 108     /* Add the working vars back into context.state[] */
 109     state[0] += a;
 110     state[1] += b;
 111     state[2] += c;
 112     state[3] += d;
 113     state[4] += e;
 114     /* Wipe variables */
 115     a = b = c = d = e = 0;
 116     memset(block, '\0', sizeof(block));
 117 }
 118
 119 /**
 120  * Run your data through this. Also used in sha1_prf.
 121  */
 122 void SHA1Update(private_sha1_hasher_t* this, u_int8_t *data, u_int32_t len)
 123 {
 124         u_int32_t i;
 125         u_int32_t j;
 126
 127     j = this->count[0];
 128     if ((this->count[0] += len << 3) < j)
 129     {
 130                 this->count[1]++;
 131     }
 132     this->count[1] += (len>>29);
 133     j = (j >> 3) & 63;
 134     if ((j + len) > 63)
 135     {
 136         memcpy(&this->buffer[j], data, (i = 64-j));
 137         SHA1Transform(this->state, this->buffer);
 138         for ( ; i + 63 < len; i += 64)
 139         {
 140             SHA1Transform(this->state, &data[i]);
 141         }
 142         j = 0;
 143     }
 144     else
 145     {
 146         i = 0;
 147     }
 148     memcpy(&this->buffer[j], &data[i], len - i);
 149 }
 150
 151
 152 /*
 153  * Add padding and return the message digest.
 154  */
 155 static void SHA1Final(private_sha1_hasher_t *this, u_int8_t *digest)
 156 {
 157         u_int32_t i;
 158         u_int8_t finalcount[8];
 159         u_int8_t c;
 160
 161     for (i = 0; i < 8; i++)
 162     {
 163         finalcount[i] = (u_int8_t)((this->count[(i >= 4 ? 0 : 1)]
 164          >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
 165     }
 166     c = 0200;
 167     SHA1Update(this, &c, 1);
 168     while ((this->count[0] & 504) != 448)
 169     {
 170                 c = 0000;
 171         SHA1Update(this, &c, 1);
 172     }
 173     SHA1Update(this, finalcount, 8);  /* Should cause a SHA1Transform() */
 174     for (i = 0; i < 20; i++)
 175     {
 176         digest[i] = (u_int8_t)((this->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
 177     }
 178 }
 179
 180 /**
 181  * Implementation of hasher_t.reset.
 182  */
 183 static void reset(private_sha1_hasher_t *this)
 184 {
 185         this->state[0] = 0x67452301;
 186     this->state[1] = 0xEFCDAB89;
 187     this->state[2] = 0x98BADCFE;
 188     this->state[3] = 0x10325476;
 189     this->state[4] = 0xC3D2E1F0;
 190     this->count[0] = 0;
 191     this->count[1] = 0;
 192 }
 193
 194 /**
 195  * Implementation of hasher_t.get_hash.
 196  */
 197 static void get_hash(private_sha1_hasher_t *this, chunk_t chunk, u_int8_t *buffer)
 198 {
 199         SHA1Update(this, chunk.ptr, chunk.len);
 200         if (buffer != NULL)
 201         {
 202                 SHA1Final(this, buffer);
 203                 reset(this);
 204         }
 205 }
 206
 207 /**
 208  * Implementation of hasher_t.allocate_hash.
 209  */
 210 static void allocate_hash(private_sha1_hasher_t *this, chunk_t chunk, chunk_t *hash)
 211 {
 212         SHA1Update(this, chunk.ptr, chunk.len);
 213         if (hash != NULL)
 214         {
 215                 hash->ptr = malloc(HASH_SIZE_SHA1);
 216                 hash->len = HASH_SIZE_SHA1;
 217
 218                 SHA1Final(this, hash->ptr);
 219                 reset(this);
 220         }
 221 }
 222
 223 /**
 224  * Implementation of hasher_t.get_hash_size.
 225  */
 226 static size_t get_hash_size(private_sha1_hasher_t *this)
 227 {
 228         return HASH_SIZE_SHA1;
 229 }
 230
 231 /**
 232  * Implementation of hasher_t.destroy.
 233  */
 234 static void destroy(private_sha1_hasher_t *this)
 235 {
 236         free(this);
 237 }
 238
 239 /*
 240  * Described in header.
 241  */
 242 sha1_hasher_t *sha1_hasher_create(hash_algorithm_t algo)
 243 {
 244         private_sha1_hasher_t *this;
 245         if (algo != HASH_SHA1)
 246         {
 247                 return NULL;
 248         }
 249         this = malloc_thing(private_sha1_hasher_t);
 250         this->public.hasher_interface.get_hash = (void (*) (hasher_t*, chunk_t, u_int8_t*))get_hash;
 251         this->public.hasher_interface.allocate_hash = (void (*) (hasher_t*, chunk_t, chunk_t*))allocate_hash;
 252         this->public.hasher_interface.get_hash_size = (size_t (*) (hasher_t*))get_hash_size;
 253         this->public.hasher_interface.reset = (void (*) (hasher_t*))reset;
 254         this->public.hasher_interface.destroy = (void (*) (hasher_t*))destroy;
 255
 256         /* initialize */
 257         reset(this);
 258
 259         return &(this->public);
 260 }
 261