lib/sha1.nit

   1 # This file is part of NIT (http://www.nitlanguage.org).
   2 #
   3 # Copyright 2014 Lucas Bajolet <r4pass@hotmail.com>
   4 #
   5 # Licensed under the Apache License, Version 2.0 (the "License");
   6 # you may not use this file except in compliance with the License.
   7 # You may obtain a copy of the License at
   8 #
   9 #                http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16
  17 # Provides methods to compute the SHA1 hash of a String
  18 module sha1
  19
  20 in "C Header" `{
  21
  22         /* This code is public-domain - it is based on libcrypt
  23          * placed in the public domain by Wei Dai and other contributors.
  24          */
  25
  26         #include <stdint.h>
  27         #include <string.h>
  28
  29         #define HASH_LENGTH 20
  30         #define BLOCK_LENGTH 64
  31
  32         union _buffer {
  33                 uint8_t b[BLOCK_LENGTH];
  34                 uint32_t w[BLOCK_LENGTH/4];
  35         };
  36
  37         union _state {
  38                 uint8_t b[HASH_LENGTH];
  39                 uint32_t w[HASH_LENGTH/4];
  40         };
  41
  42         typedef struct sha1nfo {
  43                 union _buffer buffer;
  44                 uint8_t bufferOffset;
  45                 union _state state;
  46                 uint32_t byteCount;
  47                 uint8_t keyBuffer[BLOCK_LENGTH];
  48                 uint8_t innerHash[HASH_LENGTH];
  49         } sha1nfo;
  50
  51         /**
  52          */
  53         void sha1_init(sha1nfo *s);
  54         /**
  55          */
  56         void sha1_writebyte(sha1nfo *s, uint8_t data);
  57         /**
  58          */
  59         void sha1_write(sha1nfo *s, const char *data, size_t len);
  60         /**
  61          */
  62         uint8_t* sha1_result(sha1nfo *s);
  63         /**
  64          */
  65         void sha1_initHmac(sha1nfo *s, const uint8_t* key, int keyLength);
  66         /**
  67          */
  68         uint8_t* sha1_resultHmac(sha1nfo *s);
  69 `}
  70
  71 `{
  72         #define SHA1_K0 0x5a827999
  73         #define SHA1_K20 0x6ed9eba1
  74         #define SHA1_K40 0x8f1bbcdc
  75         #define SHA1_K60 0xca62c1d6
  76
  77         const uint8_t sha1InitState[] = {
  78                 0x01,0x23,0x45,0x67, // H0
  79                 0x89,0xab,0xcd,0xef, // H1
  80                 0xfe,0xdc,0xba,0x98, // H2
  81                 0x76,0x54,0x32,0x10, // H3
  82                 0xf0,0xe1,0xd2,0xc3     // H4
  83         };
  84
  85         void sha1_init(sha1nfo *s) {
  86                 memcpy(s->state.b,sha1InitState,HASH_LENGTH);
  87                 s->byteCount = 0;
  88                 s->bufferOffset = 0;
  89         }
  90
  91         uint32_t sha1_rol32(uint32_t number, uint8_t bits) {
  92                 return ((number << bits) | (number >> (32-bits)));
  93         }
  94
  95         void sha1_hashBlock(sha1nfo *s) {
  96                 uint8_t i;
  97                 uint32_t a,b,c,d,e,t;
  98
  99                 a=s->state.w[0];
 100                 b=s->state.w[1];
 101                 c=s->state.w[2];
 102                 d=s->state.w[3];
 103                 e=s->state.w[4];
 104                 for (i=0; i<80; i++) {
 105                         if (i>=16) {
 106                                 t = s->buffer.w[(i+13)&15] ^ s->buffer.w[(i+8)&15] ^ s->buffer.w[(i+2)&15] ^ s->buffer.w[i&15];
 107                                 s->buffer.w[i&15] = sha1_rol32(t,1);
 108                         }
 109                         if (i<20) {
 110                                 t = (d ^ (b & (c ^ d))) + SHA1_K0;
 111                         } else if (i<40) {
 112                                 t = (b ^ c ^ d) + SHA1_K20;
 113                         } else if (i<60) {
 114                                 t = ((b & c) | (d & (b | c))) + SHA1_K40;
 115                         } else {
 116                                 t = (b ^ c ^ d) + SHA1_K60;
 117                         }
 118                         t+=sha1_rol32(a,5) + e + s->buffer.w[i&15];
 119                         e=d;
 120                         d=c;
 121                         c=sha1_rol32(b,30);
 122                         b=a;
 123                         a=t;
 124                 }
 125                 s->state.w[0] += a;
 126                 s->state.w[1] += b;
 127                 s->state.w[2] += c;
 128                 s->state.w[3] += d;
 129                 s->state.w[4] += e;
 130         }
 131
 132         void sha1_addUncounted(sha1nfo *s, uint8_t data) {
 133                 s->buffer.b[s->bufferOffset ^ 3] = data;
 134                 s->bufferOffset++;
 135                 if (s->bufferOffset == BLOCK_LENGTH) {
 136                         sha1_hashBlock(s);
 137                         s->bufferOffset = 0;
 138                 }
 139         }
 140
 141         void sha1_writebyte(sha1nfo *s, uint8_t data) {
 142                 ++s->byteCount;
 143                 sha1_addUncounted(s, data);
 144         }
 145
 146         void sha1_write(sha1nfo *s, const char *data, size_t len) {
 147                 for (;len--;) sha1_writebyte(s, (uint8_t) *data++);
 148         }
 149
 150         void sha1_pad(sha1nfo *s) {
 151                 // Implement SHA-1 padding (fips180-2 §5.1.1)
 152
 153                 // Pad with 0x80 followed by 0x00 until the end of the block
 154                 sha1_addUncounted(s, 0x80);
 155                 while (s->bufferOffset != 56) sha1_addUncounted(s, 0x00);
 156
 157                 // Append length in the last 8 bytes
 158                 sha1_addUncounted(s, 0); // We're only using 32 bit lengths
 159                 sha1_addUncounted(s, 0); // But SHA-1 supports 64 bit lengths
 160                 sha1_addUncounted(s, 0); // So zero pad the top bits
 161                 sha1_addUncounted(s, s->byteCount >> 29); // Shifting to multiply by 8
 162                 sha1_addUncounted(s, s->byteCount >> 21); // as SHA-1 supports bitstreams as well as
 163                 sha1_addUncounted(s, s->byteCount >> 13); // byte.
 164                 sha1_addUncounted(s, s->byteCount >> 5);
 165                 sha1_addUncounted(s, s->byteCount << 3);
 166         }
 167
 168         uint8_t* sha1_result(sha1nfo *s) {
 169                 int i;
 170                 // Pad to complete the last block
 171                 sha1_pad(s);
 172
 173                 // Swap byte order back
 174                 for (i=0; i<5; i++) {
 175                         uint32_t a,b;
 176                         a=s->state.w[i];
 177                         b=a<<24;
 178                         b|=(a<<8) & 0x00ff0000;
 179                         b|=(a>>8) & 0x0000ff00;
 180                         b|=a>>24;
 181                         s->state.w[i]=b;
 182                 }
 183
 184                 // Return pointer to hash (20 characters)
 185                 return s->state.b;
 186         }
 187
 188         #define HMAC_IPAD 0x36
 189         #define HMAC_OPAD 0x5c
 190
 191         void sha1_initHmac(sha1nfo *s, const uint8_t* key, int keyLength) {
 192                 uint8_t i;
 193                 memset(s->keyBuffer, 0, BLOCK_LENGTH);
 194                 if (keyLength > BLOCK_LENGTH) {
 195                         // Hash long keys
 196                         sha1_init(s);
 197                         for (;keyLength--;) sha1_writebyte(s, *key++);
 198                         memcpy(s->keyBuffer, sha1_result(s), HASH_LENGTH);
 199                 } else {
 200                         // Block length keys are used as is
 201                         memcpy(s->keyBuffer, key, keyLength);
 202                 }
 203                 // Start inner hash
 204                 sha1_init(s);
 205                 for (i=0; i<BLOCK_LENGTH; i++) {
 206                         sha1_writebyte(s, s->keyBuffer[i] ^ HMAC_IPAD);
 207                 }
 208         }
 209
 210         uint8_t* sha1_resultHmac(sha1nfo *s) {
 211                 uint8_t i;
 212                 // Complete inner hash
 213                 memcpy(s->innerHash,sha1_result(s),HASH_LENGTH);
 214                 // Calculate outer hash
 215                 sha1_init(s);
 216                 for (i=0; i<BLOCK_LENGTH; i++) sha1_writebyte(s, s->keyBuffer[i] ^ HMAC_OPAD);
 217                 for (i=0; i<HASH_LENGTH; i++) sha1_writebyte(s, s->innerHash[i]);
 218                 return sha1_result(s);
 219         }
 220 `}
 221
 222 redef class String
 223
 224         # Computes the SHA1 of the receiver
 225         #
 226         # Returns a digest of 20 bytes as a String,
 227         # note that all the characters are not necessarily ASCII.
 228         # If you want the hex string version of the digest, use
 229         # sha1_to_s.
 230         #
 231         #     import base64
 232         #     assert "The quick brown fox jumps over the lazy dog".sha1.encode_base64 == "L9ThxnotKPzthJ7hu3bnORuT6xI="
 233         fun sha1: String import String.to_cstring, String.length, NativeString.to_s_with_length `{
 234                 uint32_t a;
 235                 sha1nfo s;
 236
 237                 sha1_init(&s);
 238                 sha1_write(&s, String_to_cstring(recv), String_length(recv));
 239                 uint8_t* digest = sha1_result(&s);
 240
 241                 char* digested = malloc(21);
 242
 243                 memcpy(digested, digest, 20);
 244
 245                 digested[20] = '\0';
 246
 247                 return NativeString_to_s_with_length(digested, 20);
 248         `}
 249
 250         # Computes the SHA1 of the receiver.
 251         #
 252         # Returns a 40 char String containing the Hexadecimal
 253         # Digest in its Char form.
 254         #
 255         #     assert "The quick brown fox jumps over the lazy dog".sha1_to_s == "2FD4E1C67A2D28FCED849EE1BB76E7391B93EB12"
 256         fun sha1_to_s: String import String.to_cstring, String.length, NativeString.to_s_with_length `{
 257                 uint32_t a;
 258                 sha1nfo s;
 259
 260                 sha1_init(&s);
 261                 sha1_write(&s, String_to_cstring(recv), String_length(recv));
 262                 uint8_t* digest = sha1_result(&s);
 263
 264                 char* ret_str = malloc(41);
 265                 char* hexmap = "0123456789ABCDEF";
 266
 267                 int i;
 268                 for(i=0;i<20;i++){
 269                         uint8_t q = digest[i];
 270                         ret_str[i*2] = hexmap[q >> 4];
 271                         ret_str[(i*2)+1] = hexmap[q & 0x0F];
 272                 }
 273                 ret_str[40] = '\0';
 274
 275                 return NativeString_to_s_with_length(ret_str, 40);
 276         `}
 277
 278 end
 279