The Tor Browser: netwerk/srtp/src/crypto/hash/sha1.c@6474c204b198 (annotated)

netwerk/srtp/src/crypto/hash/sha1.c@6474c204b198 (annotated)

netwerk/srtp/src/crypto/hash/sha1.c

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /*
  * sha1.c
  *
  * an implementation of the Secure Hash Algorithm v.1 (SHA-1),
  * specified in FIPS 180-1
  *
  * David A. McGrew
  * Cisco Systems, Inc.
  */
 /*
  *
  * Copyright (c) 2001-2006, Cisco Systems, Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  *   Redistributions of source code must retain the above copyright
  *   notice, this list of conditions and the following disclaimer.
  *
  *   Redistributions in binary form must reproduce the above
  *   copyright notice, this list of conditions and the following
  *   disclaimer in the documentation and/or other materials provided
  *   with the distribution.
  *
  *   Neither the name of the Cisco Systems, Inc. nor the names of its
  *   contributors may be used to endorse or promote products derived
  *   from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  */
 #include "sha1.h"
 debug_module_t mod_sha1 = {
 ,                 /* debugging is off by default */
   "sha-1"            /* printable module name       */
 };
 /* SN == Rotate left N bits */
 #define S1(X)  ((X << 1)  | (X >> 31))
 #define S5(X)  ((X << 5)  | (X >> 27))
 #define S30(X) ((X << 30) | (X >> 2))
 #define f0(B,C,D) ((B & C) | (~B & D))
 #define f1(B,C,D) (B ^ C ^ D)
 #define f2(B,C,D) ((B & C) | (B & D) | (C & D))
 #define f3(B,C,D) (B ^ C ^ D)
 /*
  * nota bene: the variable K0 appears in the curses library, so we
  * give longer names to these variables to avoid spurious warnings
  * on systems that uses curses
  */
 uint32_t SHA_K0 = 0x5A827999;   /* Kt for 0  <= t <= 19 */
 uint32_t SHA_K1 = 0x6ED9EBA1;   /* Kt for 20 <= t <= 39 */
 uint32_t SHA_K2 = 0x8F1BBCDC;   /* Kt for 40 <= t <= 59 */
 uint32_t SHA_K3 = 0xCA62C1D6;   /* Kt for 60 <= t <= 79 */
 void
 sha1(const uint8_t *msg,  int octets_in_msg, uint32_t hash_value[5]) {
   sha1_ctx_t ctx;
   sha1_init(&ctx);
   sha1_update(&ctx, msg, octets_in_msg);
   sha1_final(&ctx, hash_value);
 }
 /*
  *  sha1_core(M, H) computes the core compression function, where M is
  *  the next part of the message (in network byte order) and H is the
  *  intermediate state { H0, H1, ...} (in host byte order)
  *
  *  this function does not do any of the padding required in the
  *  complete SHA1 function
  *
  *  this function is used in the SEAL 3.0 key setup routines
  *  (crypto/cipher/seal.c)
  */
 void
 sha1_core(const uint32_t M[16], uint32_t hash_value[5]) {
   uint32_t H0;
   uint32_t H1;
   uint32_t H2;
   uint32_t H3;
   uint32_t H4;
   uint32_t W[80];
   uint32_t A, B, C, D, E, TEMP;
   int t;
   /* copy hash_value into H0, H1, H2, H3, H4 */
   H0 = hash_value[0];
   H1 = hash_value[1];
   H2 = hash_value[2];
   H3 = hash_value[3];
   H4 = hash_value[4];
   /* copy/xor message into array */
   W[0]  = be32_to_cpu(M[0]);
   W[1]  = be32_to_cpu(M[1]);
   W[2]  = be32_to_cpu(M[2]);
   W[3]  = be32_to_cpu(M[3]);
   W[4]  = be32_to_cpu(M[4]);
   W[5]  = be32_to_cpu(M[5]);
   W[6]  = be32_to_cpu(M[6]);
   W[7]  = be32_to_cpu(M[7]);
   W[8]  = be32_to_cpu(M[8]);
   W[9]  = be32_to_cpu(M[9]);
   W[10] = be32_to_cpu(M[10]);
   W[11] = be32_to_cpu(M[11]);
   W[12] = be32_to_cpu(M[12]);
   W[13] = be32_to_cpu(M[13]);
   W[14] = be32_to_cpu(M[14]);
   W[15] = be32_to_cpu(M[15]);
   TEMP = W[13] ^ W[8]  ^ W[2]  ^ W[0];  W[16] = S1(TEMP);
   TEMP = W[14] ^ W[9]  ^ W[3]  ^ W[1];  W[17] = S1(TEMP);
   TEMP = W[15] ^ W[10] ^ W[4]  ^ W[2];  W[18] = S1(TEMP);
   TEMP = W[16] ^ W[11] ^ W[5]  ^ W[3];  W[19] = S1(TEMP);
   TEMP = W[17] ^ W[12] ^ W[6]  ^ W[4];  W[20] = S1(TEMP);
   TEMP = W[18] ^ W[13] ^ W[7]  ^ W[5];  W[21] = S1(TEMP);
   TEMP = W[19] ^ W[14] ^ W[8]  ^ W[6];  W[22] = S1(TEMP);
   TEMP = W[20] ^ W[15] ^ W[9]  ^ W[7];  W[23] = S1(TEMP);
   TEMP = W[21] ^ W[16] ^ W[10] ^ W[8];  W[24] = S1(TEMP);
   TEMP = W[22] ^ W[17] ^ W[11] ^ W[9];  W[25] = S1(TEMP);
   TEMP = W[23] ^ W[18] ^ W[12] ^ W[10]; W[26] = S1(TEMP);
   TEMP = W[24] ^ W[19] ^ W[13] ^ W[11]; W[27] = S1(TEMP);
   TEMP = W[25] ^ W[20] ^ W[14] ^ W[12]; W[28] = S1(TEMP);
   TEMP = W[26] ^ W[21] ^ W[15] ^ W[13]; W[29] = S1(TEMP);
   TEMP = W[27] ^ W[22] ^ W[16] ^ W[14]; W[30] = S1(TEMP);
   TEMP = W[28] ^ W[23] ^ W[17] ^ W[15]; W[31] = S1(TEMP);
   /* process the remainder of the array */
   for (t=32; t < 80; t++) {
     TEMP = W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16];
     W[t] = S1(TEMP);
   }
   A = H0; B = H1; C = H2; D = H3; E = H4;
   for (t=0; t < 20; t++) {
     TEMP = S5(A) + f0(B,C,D) + E + W[t] + SHA_K0;
     E = D; D = C; C = S30(B); B = A; A = TEMP;
   }
   for (   ; t < 40; t++) {
     TEMP = S5(A) + f1(B,C,D) + E + W[t] + SHA_K1;
     E = D; D = C; C = S30(B); B = A; A = TEMP;
   }
   for (   ; t < 60; t++) {
     TEMP = S5(A) + f2(B,C,D) + E + W[t] + SHA_K2;
     E = D; D = C; C = S30(B); B = A; A = TEMP;
   }
   for (   ; t < 80; t++) {
     TEMP = S5(A) + f3(B,C,D) + E + W[t] + SHA_K3;
     E = D; D = C; C = S30(B); B = A; A = TEMP;
   }
   hash_value[0] = H0 + A;
   hash_value[1] = H1 + B;
   hash_value[2] = H2 + C;
   hash_value[3] = H3 + D;
   hash_value[4] = H4 + E;
   return;
 }
 void
 sha1_init(sha1_ctx_t *ctx) {
   /* initialize state vector */
   ctx->H[0] = 0x67452301;
   ctx->H[1] = 0xefcdab89;
   ctx->H[2] = 0x98badcfe;
   ctx->H[3] = 0x10325476;
   ctx->H[4] = 0xc3d2e1f0;
   /* indicate that message buffer is empty */
   ctx->octets_in_buffer = 0;
   /* reset message bit-count to zero */
   ctx->num_bits_in_msg = 0;
 }
 void
 sha1_update(sha1_ctx_t *ctx, const uint8_t *msg, int octets_in_msg) {
   int i;
   uint8_t *buf = (uint8_t *)ctx->M;
   /* update message bit-count */
   ctx->num_bits_in_msg += octets_in_msg * 8;
   /* loop over 16-word blocks of M */
   while (octets_in_msg > 0) {
     if (octets_in_msg + ctx->octets_in_buffer >= 64) {
       /*
        * copy words of M into msg buffer until that buffer is full,
        * converting them into host byte order as needed
        */
       octets_in_msg -= (64 - ctx->octets_in_buffer);
       for (i=ctx->octets_in_buffer; i < 64; i++)
 	buf[i] = *msg++;
       ctx->octets_in_buffer = 0;
       /* process a whole block */
       debug_print(mod_sha1, "(update) running sha1_core()", NULL);
       sha1_core(ctx->M, ctx->H);
     } else {
       debug_print(mod_sha1, "(update) not running sha1_core()", NULL);
       for (i=ctx->octets_in_buffer;
 	   i < (ctx->octets_in_buffer + octets_in_msg); i++)
 	buf[i] = *msg++;
       ctx->octets_in_buffer += octets_in_msg;
       octets_in_msg = 0;
     }
   }
 }
 /*
  * sha1_final(ctx, output) computes the result for ctx and copies it
  * into the twenty octets located at *output
  */
 void
 sha1_final(sha1_ctx_t *ctx, uint32_t *output) {
   uint32_t A, B, C, D, E, TEMP;
   uint32_t W[80];
   int i, t;
   /*
    * process the remaining octets_in_buffer, padding and terminating as
    * necessary
    */
   {
     int tail = ctx->octets_in_buffer % 4;
     /* copy/xor message into array */
     for (i=0; i < (ctx->octets_in_buffer+3)/4; i++)
       W[i]  = be32_to_cpu(ctx->M[i]);
     /* set the high bit of the octet immediately following the message */
     switch (tail) {
     case (3):
       W[i-1] = (be32_to_cpu(ctx->M[i-1]) & 0xffffff00) | 0x80;
       W[i] = 0x0;
       break;
     case (2):
       W[i-1] = (be32_to_cpu(ctx->M[i-1]) & 0xffff0000) | 0x8000;
       W[i] = 0x0;
       break;
     case (1):
       W[i-1] = (be32_to_cpu(ctx->M[i-1]) & 0xff000000) | 0x800000;
       W[i] = 0x0;
       break;
     case (0):
       W[i] = 0x80000000;
       break;
     }
     /* zeroize remaining words */
     for (i++   ; i < 15; i++)
       W[i] = 0x0;
     /*
      * if there is room at the end of the word array, then set the
      * last word to the bit-length of the message; otherwise, set that
      * word to zero and then we need to do one more run of the
      * compression algo.
      */
     if (ctx->octets_in_buffer < 56)
       W[15] = ctx->num_bits_in_msg;
     else if (ctx->octets_in_buffer < 60)
       W[15] = 0x0;
     /* process the word array */
     for (t=16; t < 80; t++) {
       TEMP = W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16];
       W[t] = S1(TEMP);
     }
     A = ctx->H[0];
     B = ctx->H[1];
     C = ctx->H[2];
     D = ctx->H[3];
     E = ctx->H[4];
     for (t=0; t < 20; t++) {
       TEMP = S5(A) + f0(B,C,D) + E + W[t] + SHA_K0;
       E = D; D = C; C = S30(B); B = A; A = TEMP;
     }
     for (   ; t < 40; t++) {
       TEMP = S5(A) + f1(B,C,D) + E + W[t] + SHA_K1;
       E = D; D = C; C = S30(B); B = A; A = TEMP;
     }
     for (   ; t < 60; t++) {
       TEMP = S5(A) + f2(B,C,D) + E + W[t] + SHA_K2;
       E = D; D = C; C = S30(B); B = A; A = TEMP;
     }
     for (   ; t < 80; t++) {
       TEMP = S5(A) + f3(B,C,D) + E + W[t] + SHA_K3;
       E = D; D = C; C = S30(B); B = A; A = TEMP;
     }
     ctx->H[0] += A;
     ctx->H[1] += B;
     ctx->H[2] += C;
     ctx->H[3] += D;
     ctx->H[4] += E;
   }
   debug_print(mod_sha1, "(final) running sha1_core()", NULL);
   if (ctx->octets_in_buffer >= 56) {
     debug_print(mod_sha1, "(final) running sha1_core() again", NULL);
     /* we need to do one final run of the compression algo */
     /*
      * set initial part of word array to zeros, and set the
      * final part to the number of bits in the message
      */
     for (i=0; i < 15; i++)
       W[i] = 0x0;
     W[15] = ctx->num_bits_in_msg;
     /* process the word array */
     for (t=16; t < 80; t++) {
       TEMP = W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16];
       W[t] = S1(TEMP);
     }
     A = ctx->H[0];
     B = ctx->H[1];
     C = ctx->H[2];
     D = ctx->H[3];
     E = ctx->H[4];
     for (t=0; t < 20; t++) {
       TEMP = S5(A) + f0(B,C,D) + E + W[t] + SHA_K0;
       E = D; D = C; C = S30(B); B = A; A = TEMP;
     }
     for (   ; t < 40; t++) {
       TEMP = S5(A) + f1(B,C,D) + E + W[t] + SHA_K1;
       E = D; D = C; C = S30(B); B = A; A = TEMP;
     }
     for (   ; t < 60; t++) {
       TEMP = S5(A) + f2(B,C,D) + E + W[t] + SHA_K2;
       E = D; D = C; C = S30(B); B = A; A = TEMP;
     }
     for (   ; t < 80; t++) {
       TEMP = S5(A) + f3(B,C,D) + E + W[t] + SHA_K3;
       E = D; D = C; C = S30(B); B = A; A = TEMP;
     }
     ctx->H[0] += A;
     ctx->H[1] += B;
     ctx->H[2] += C;
     ctx->H[3] += D;
     ctx->H[4] += E;
   }
   /* copy result into output buffer */
   output[0] = be32_to_cpu(ctx->H[0]);
   output[1] = be32_to_cpu(ctx->H[1]);
   output[2] = be32_to_cpu(ctx->H[2]);
   output[3] = be32_to_cpu(ctx->H[3]);
   output[4] = be32_to_cpu(ctx->H[4]);
   /* indicate that message buffer in context is empty */
   ctx->octets_in_buffer = 0;
   return;
 }

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netwerk/srtp/src/crypto/hash/sha1.c@6474c204b198 (annotated)

netwerk/srtp/src/crypto/hash/sha1.c