lib/sha1.c

   1 /*
   2  * This file is from the Apache Portable Runtime Library.
   3  * The full upstream copyright and license statement is included below.
   4  * Modifications copyright (c) 2009 Nicira Networks.
   5  */
   6
   7 /* Licensed to the Apache Software Foundation (ASF) under one or more
   8  * contributor license agreements.  See the NOTICE file distributed with
   9  * this work for additional information regarding copyright ownership.
  10  * The ASF licenses this file to You under the Apache License, Version 2.0
  11  * (the "License"); you may not use this file except in compliance with
  12  * the License.  You may obtain a copy of the License at
  13  *
  14  *     http://www.apache.org/licenses/LICENSE-2.0
  15  *
  16  * Unless required by applicable law or agreed to in writing, software
  17  * distributed under the License is distributed on an "AS IS" BASIS,
  18  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  19  * See the License for the specific language governing permissions and
  20  * limitations under the License.
  21  */
  22
  23 /* This software also makes use of the following component:
  24  *
  25  * NIST Secure Hash Algorithm
  26  *      heavily modified by Uwe Hollerbach uh@alumni.caltech edu
  27  *      from Peter C. Gutmann's implementation as found in
  28  *      Applied Cryptography by Bruce Schneier
  29  *      This code is hereby placed in the public domain
  30  */
  31
  32 #include <config.h>
  33 #include "sha1.h"
  34 #include <ctype.h>
  35 #include <string.h>
  36 #include "util.h"
  37
  38 /* a bit faster & bigger, if defined */
  39 #define UNROLL_LOOPS
  40
  41 /* SHA f()-functions */
  42 static inline uint32_t
  43 f1(uint32_t x, uint32_t y, uint32_t z)
  44 {
  45     return (x & y) | (~x & z);
  46 }
  47
  48 static inline uint32_t
  49 f2(uint32_t x, uint32_t y, uint32_t z)
  50 {
  51     return x ^ y ^ z;
  52 }
  53
  54 static inline uint32_t
  55 f3(uint32_t x, uint32_t y, uint32_t z)
  56 {
  57     return (x & y) | (x & z) | (y & z);
  58 }
  59
  60 static inline uint32_t
  61 f4(uint32_t x, uint32_t y, uint32_t z)
  62 {
  63     return x ^ y ^ z;
  64 }
  65
  66 /* SHA constants */
  67 #define CONST1          0x5a827999L
  68 #define CONST2          0x6ed9eba1L
  69 #define CONST3          0x8f1bbcdcL
  70 #define CONST4          0xca62c1d6L
  71
  72 /* 32-bit rotate */
  73 static inline uint32_t
  74 rotate32(uint32_t x, int n)
  75 {
  76     return ((x << n) | (x >> (32 - n)));
  77 }
  78
  79 #define FUNC(n, i)                                                      \
  80     do {                                                                \
  81         temp = rotate32(A, 5) + f##n(B, C, D) + E + W[i] + CONST##n;    \
  82         E = D;                                                          \
  83         D = C;                                                          \
  84         C = rotate32(B, 30);                                            \
  85         B = A;                                                          \
  86         A = temp;                                                       \
  87     } while (0)
  88
  89 #define SHA_BLOCK_SIZE           64
  90
  91 /* Do SHA transformation. */
  92 static void
  93 sha_transform(struct sha1_ctx *sha_info)
  94 {
  95     int i;
  96     uint32_t temp, A, B, C, D, E, W[80];
  97
  98     for (i = 0; i < 16; ++i) {
  99         W[i] = sha_info->data[i];
 100     }
 101     for (i = 16; i < 80; ++i) {
 102         W[i] = W[i-3] ^ W[i-8] ^ W[i-14] ^ W[i-16];
 103         W[i] = rotate32(W[i], 1);
 104     }
 105     A = sha_info->digest[0];
 106     B = sha_info->digest[1];
 107     C = sha_info->digest[2];
 108     D = sha_info->digest[3];
 109     E = sha_info->digest[4];
 110 #ifdef UNROLL_LOOPS
 111     FUNC(1, 0);  FUNC(1, 1);  FUNC(1, 2);  FUNC(1, 3);  FUNC(1, 4);
 112     FUNC(1, 5);  FUNC(1, 6);  FUNC(1, 7);  FUNC(1, 8);  FUNC(1, 9);
 113     FUNC(1,10);  FUNC(1,11);  FUNC(1,12);  FUNC(1,13);  FUNC(1,14);
 114     FUNC(1,15);  FUNC(1,16);  FUNC(1,17);  FUNC(1,18);  FUNC(1,19);
 115
 116     FUNC(2,20);  FUNC(2,21);  FUNC(2,22);  FUNC(2,23);  FUNC(2,24);
 117     FUNC(2,25);  FUNC(2,26);  FUNC(2,27);  FUNC(2,28);  FUNC(2,29);
 118     FUNC(2,30);  FUNC(2,31);  FUNC(2,32);  FUNC(2,33);  FUNC(2,34);
 119     FUNC(2,35);  FUNC(2,36);  FUNC(2,37);  FUNC(2,38);  FUNC(2,39);
 120
 121     FUNC(3,40);  FUNC(3,41);  FUNC(3,42);  FUNC(3,43);  FUNC(3,44);
 122     FUNC(3,45);  FUNC(3,46);  FUNC(3,47);  FUNC(3,48);  FUNC(3,49);
 123     FUNC(3,50);  FUNC(3,51);  FUNC(3,52);  FUNC(3,53);  FUNC(3,54);
 124     FUNC(3,55);  FUNC(3,56);  FUNC(3,57);  FUNC(3,58);  FUNC(3,59);
 125
 126     FUNC(4,60);  FUNC(4,61);  FUNC(4,62);  FUNC(4,63);  FUNC(4,64);
 127     FUNC(4,65);  FUNC(4,66);  FUNC(4,67);  FUNC(4,68);  FUNC(4,69);
 128     FUNC(4,70);  FUNC(4,71);  FUNC(4,72);  FUNC(4,73);  FUNC(4,74);
 129     FUNC(4,75);  FUNC(4,76);  FUNC(4,77);  FUNC(4,78);  FUNC(4,79);
 130 #else /* !UNROLL_LOOPS */
 131     for (i = 0; i < 20; ++i) {
 132         FUNC(1,i);
 133     }
 134     for (i = 20; i < 40; ++i) {
 135         FUNC(2,i);
 136     }
 137     for (i = 40; i < 60; ++i) {
 138         FUNC(3,i);
 139     }
 140     for (i = 60; i < 80; ++i) {
 141         FUNC(4,i);
 142     }
 143 #endif /* !UNROLL_LOOPS */
 144     sha_info->digest[0] += A;
 145     sha_info->digest[1] += B;
 146     sha_info->digest[2] += C;
 147     sha_info->digest[3] += D;
 148     sha_info->digest[4] += E;
 149 }
 150
 151 /* 'count' is the number of bytes to do an endian flip. */
 152 static void
 153 maybe_byte_reverse(uint32_t *buffer, int count)
 154 {
 155     int i;
 156     uint8_t ct[4], *cp;
 157
 158 #if !WORDS_BIGENDIAN
 159         count /= sizeof(uint32_t);
 160         cp = (uint8_t *) buffer;
 161         for (i = 0; i < count; i++) {
 162             ct[0] = cp[0];
 163             ct[1] = cp[1];
 164             ct[2] = cp[2];
 165             ct[3] = cp[3];
 166             cp[0] = ct[3];
 167             cp[1] = ct[2];
 168             cp[2] = ct[1];
 169             cp[3] = ct[0];
 170             cp += sizeof(uint32_t);
 171         }
 172 #endif
 173 }
 174
 175 /*
 176  * Initialize the SHA digest.
 177  * context: The SHA context to initialize
 178  */
 179 void
 180 sha1_init(struct sha1_ctx *sha_info)
 181 {
 182     sha_info->digest[0] = 0x67452301L;
 183     sha_info->digest[1] = 0xefcdab89L;
 184     sha_info->digest[2] = 0x98badcfeL;
 185     sha_info->digest[3] = 0x10325476L;
 186     sha_info->digest[4] = 0xc3d2e1f0L;
 187     sha_info->count_lo = 0L;
 188     sha_info->count_hi = 0L;
 189     sha_info->local = 0;
 190 }
 191
 192 /*
 193  * Update the SHA digest.
 194  * context: The SHA1 context to update.
 195  * input: The buffer to add to the SHA digest.
 196  * inputLen: The length of the input buffer.
 197  */
 198 void
 199 sha1_update(struct sha1_ctx *ctx, const void *buffer_, size_t count)
 200 {
 201     const uint8_t *buffer = buffer_;
 202     unsigned int i;
 203
 204     if ((ctx->count_lo + (count << 3)) < ctx->count_lo) {
 205         ctx->count_hi++;
 206     }
 207     ctx->count_lo += count << 3;
 208     ctx->count_hi += count >> 29;
 209     if (ctx->local) {
 210         i = SHA_BLOCK_SIZE - ctx->local;
 211         if (i > count) {
 212             i = count;
 213         }
 214         memcpy(((uint8_t *) ctx->data) + ctx->local, buffer, i);
 215         count -= i;
 216         buffer += i;
 217         ctx->local += i;
 218         if (ctx->local == SHA_BLOCK_SIZE) {
 219             maybe_byte_reverse(ctx->data, SHA_BLOCK_SIZE);
 220             sha_transform(ctx);
 221         } else {
 222             return;
 223         }
 224     }
 225     while (count >= SHA_BLOCK_SIZE) {
 226         memcpy(ctx->data, buffer, SHA_BLOCK_SIZE);
 227         buffer += SHA_BLOCK_SIZE;
 228         count -= SHA_BLOCK_SIZE;
 229         maybe_byte_reverse(ctx->data, SHA_BLOCK_SIZE);
 230         sha_transform(ctx);
 231     }
 232     memcpy(ctx->data, buffer, count);
 233     ctx->local = count;
 234 }
 235
 236 /*
 237  * Finish computing the SHA digest.
 238  * digest: the output buffer in which to store the digest.
 239  * context: The context to finalize.
 240  */
 241 void
 242 sha1_final(struct sha1_ctx *ctx, uint8_t digest[SHA1_DIGEST_SIZE])
 243 {
 244     int count, i, j;
 245     uint32_t lo_bit_count, hi_bit_count, k;
 246
 247     lo_bit_count = ctx->count_lo;
 248     hi_bit_count = ctx->count_hi;
 249     count = (int) ((lo_bit_count >> 3) & 0x3f);
 250     ((uint8_t *) ctx->data)[count++] = 0x80;
 251     if (count > SHA_BLOCK_SIZE - 8) {
 252         memset(((uint8_t *) ctx->data) + count, 0, SHA_BLOCK_SIZE - count);
 253         maybe_byte_reverse(ctx->data, SHA_BLOCK_SIZE);
 254         sha_transform(ctx);
 255         memset((uint8_t *) ctx->data, 0, SHA_BLOCK_SIZE - 8);
 256     } else {
 257         memset(((uint8_t *) ctx->data) + count, 0,
 258                SHA_BLOCK_SIZE - 8 - count);
 259     }
 260     maybe_byte_reverse(ctx->data, SHA_BLOCK_SIZE);
 261     ctx->data[14] = hi_bit_count;
 262     ctx->data[15] = lo_bit_count;
 263     sha_transform(ctx);
 264
 265     for (i = j = 0; j < SHA1_DIGEST_SIZE; i++) {
 266         k = ctx->digest[i];
 267         digest[j++] = k >> 24;
 268         digest[j++] = k >> 16;
 269         digest[j++] = k >> 8;
 270         digest[j++] = k;
 271     }
 272 }
 273
 274 /* Computes the hash of 'n' bytes in 'data' into 'digest'. */
 275 void
 276 sha1_bytes(const void *data, size_t n, uint8_t digest[SHA1_DIGEST_SIZE])
 277 {
 278     struct sha1_ctx ctx;
 279
 280     sha1_init(&ctx);
 281     sha1_update(&ctx, data, n);
 282     sha1_final(&ctx, digest);
 283 }
 284
 285 void
 286 sha1_to_hex(const uint8_t digest[SHA1_DIGEST_SIZE],
 287             char hex[SHA1_HEX_DIGEST_LEN + 1])
 288 {
 289     int i;
 290
 291     for (i = 0; i < SHA1_DIGEST_SIZE; i++) {
 292         *hex++ = "0123456789abcdef"[digest[i] >> 4];
 293         *hex++ = "0123456789abcdef"[digest[i] & 15];
 294     }
 295     *hex = '\0';
 296 }
 297
 298 bool
 299 sha1_from_hex(uint8_t digest[SHA1_DIGEST_SIZE], const char *hex)
 300 {
 301     int i;
 302
 303     for (i = 0; i < SHA1_DIGEST_SIZE; i++) {
 304         if (!isxdigit(hex[0]) || !isxdigit(hex[1])) {
 305             return false;
 306         }
 307         digest[i] = (hexit_value(hex[0]) << 4) | hexit_value(hex[1]);
 308         hex += 2;
 309     }
 310     return true;
 311 }
 312