/** Local implementation of the SHA1 hashing scheme

 *

 * SHA-1 in C 100% Public Domain

 *

 * @file src/lib/util/sha1.c

 *

 * @author Steve Reid (steve@edmweb.com)

 */

RCSID("$Id: b5f509fb5eb8394674245c81ba412ce93bcbca91 $")

#include <freeradius-devel/util/sha1.h>

#ifndef WITH_OPENSSL_SHA1

#  define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))

/* blk0() and blk() perform the initial expand. */

/* I got the idea of expanding during the round function from SSLeay */

#  define blk0(i) (block->l[i] = htonl(block->l[i]))

#  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))

/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */

#  define R0(v,w,x,y,z,i) do { z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30); } while (0)

#  define R1(v,w,x,y,z,i) do { z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30); } while (0)

#  define R2(v,w,x,y,z,i) do { z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30); } while (0)

#  define R3(v,w,x,y,z,i) do { z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30); } while (0)

#  define R4(v,w,x,y,z,i) do { z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30); } while (0)

/* Hash a single 512-bit block. This is the core of the algorithm. */

void fr_sha1_transform(uint32_t state[static 5], uint8_t const buffer[static 64])

{

  uint32_t a, b, c, d, e;

  typedef union {

    uint8_t c[64];

    uint32_t l[16];

  } CHAR64LONG16;

  CHAR64LONG16 *block;

  uint64_t workspace[8];

  block = (CHAR64LONG16*)workspace;

  memcpy(block, buffer, 64);

  /* Copy context->state[] to working vars */

  a = state[0];

  b = state[1];

  c = state[2];

  d = state[3];

  e = state[4];

  /* 4 rounds of 20 operations each. Loop unrolled. */

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  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);

  /* Add the working vars back into context.state[] */

  state[0] += a;

  state[1] += b;

  state[2] += c;

  state[3] += d;

  state[4] += e;

#  ifndef STATIC_ANALYZER

  /* Wipe variables */

  a = b = c = d = e = 0;

#  endif

}

/* fr_sha1_init - Initialize new context */

void fr_sha1_init(fr_sha1_ctx* context)

{

  /* SHA1 initialization constants */

  context->state[0] = 0x67452301;

  context->state[1] = 0xEFCDAB89;

  context->state[2] = 0x98BADCFE;

  context->state[3] = 0x10325476;

  context->state[4] = 0xC3D2E1F0;

  context->count[0] = context->count[1] = 0;

}

/* Run your data through this. */

void fr_sha1_update(fr_sha1_ctx *context, uint8_t const *in, size_t len)

{

  unsigned int i, j;

  /*

   *  If len == 0, there's nothing to do:

   *  First, len == 0 impolies len * 8 == 0, so the contents of

   *  context->count wouldn't change.

   *  j by construction is <= 63, so if len == 0, j + len == j <= 63, and

   *  i would be set to 0 and the final memcpy() would "copy" 0

   *  bytes, so the contents of context->buffer wouldn't change either.

   */

  if (len == 0) return;

  j = (context->count[0] >> 3) & 63;

  if ((context->count[0] += len << 3) < (len << 3)) {

    context->count[1]++;

  }

  context->count[1] += (len >> 29);

  if ((j + len) > 63) {

    memcpy(&context->buffer[j], in, (i = 64-j));

    fr_sha1_transform(context->state, context->buffer);

    for ( ; i + 63 < len; i += 64) {

      fr_sha1_transform(context->state, &in[i]);

    }

    j = 0;

  } else {

    i = 0;

  }

  memcpy(&context->buffer[j], &in[i], len - i);

}

/* Add padding and return the message digest. */

void fr_sha1_final(uint8_t digest[static SHA1_DIGEST_LENGTH], fr_sha1_ctx *context)

{

  uint32_t i, j;

  uint8_t finalcount[8];

  for (i = 0; i < 8; i++) {

    finalcount[i] = (uint8_t)((context->count[(i >= 4 ? 0 : 1)] >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */

  }

  fr_sha1_update(context, (unsigned char const *) "\200", 1);

  while ((context->count[0] & 504) != 448) {

    fr_sha1_update(context, (unsigned char const *) "\0", 1);

  }

  fr_sha1_update(context, finalcount, 8);  /* Should cause a fr_sha1_transform() */

  for (i = 0; i < 20; i++) {

    digest[i] = (uint8_t)((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);

  }

#  ifndef STATIC_ANALYZER

  /* Wipe variables */

  i = j = 0;

  memset(context->buffer, 0, 64);

  memset(context->state, 0, 20);

  memset(context->count, 0, 8);

  memset(&finalcount, 0, 8);

#  endif

#  ifdef SHA1HANDSOFF  /* make fr_sha1_transform overwrite it's own static vars */

  fr_sha1_transform(context->state, context->buffer);

#  endif

}

void fr_sha1_final_no_len(uint8_t digest[static SHA1_DIGEST_LENGTH], fr_sha1_ctx *context)

{

  uint32_t i, j;

  for (i = 0; i < 20; i++) {

    digest[i] = (uint8_t)((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);

  }

#  ifndef STATIC_ANALYZER

  /* Wipe variables */

  i = j = 0;

  memset(context->buffer, 0, 64);

  memset(context->state, 0, 20);

  memset(context->count, 0, 8);

#  endif

#  ifdef SHA1HANDSOFF  /* make fr_sha1_transform overwrite it's own static vars */

  fr_sha1_transform(context->state, context->buffer);

#  endif

}

#endif