/**@CFILE rc4.c Arcfour pseudorandom generator.
 *
 * @author Pekka Pessi <ppessi@hut.fi>
 *
 * Copyright (c) 1996 Pekka Pessi. All rights reserved.
 *
 * This source code is provided for unrestricted use. Users may copy or
 * modify this source code without charge.
 *
 * THIS SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND
 * INCLUDING THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE
 * PRACTICE.
 *
 * This source code is provided with no support and without any obligation
 * on the part of author to assist in its use, correction, modification or
 * enhancement.
 *
 * AUTHOR SHALL HAVE NO LIABILITY WITH RESPECT TO THE INFRINGEMENT OF
 * COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE OR ANY PART
 * THEREOF.
 *
 * In no event will author be liable for any lost revenue or profits or
 * other special, indirect and consequential damages, even if author has
 * been advised of the possibility of such damages.
 *
 * @date Created: Sun Jun  9 12:43:17 1996 ppessi
 */

#include "config.h"

#include "sofia-sip/rc4.h"

void rc4_init(const void *vseed, isize_t seed_len, rc4_t *state) {
  short i; rc4_u8 j; rc4_u8 k;

  const rc4_u8 *seed = (const rc4_u8 *)vseed;
  rc4_u8 *array = state->rc4_array;

  state->rc4_i = 0;
  state->rc4_j = 0;

  for (i = 0; i < 256; i++)
    array[i] = (rc4_u8) i;

  for (i = 0, j = 0, k = 0;
       i < 256;
       i++, k++, k >= seed_len ? k = 0 : 0) {
    rc4_u8 a = array[i];
    rc4_u8 b = array[j += a + seed[k]];

    array[i] = b;
    array[j] = a;
  }
}

void rc4(void *buffer, isize_t len, rc4_t *state) {
  rc4_u8 *buf = (rc4_u8 *)buffer;
  rc4_u8 *array = state->rc4_array;
  rc4_u8 i = state->rc4_i;
  rc4_u8 j = state->rc4_j;

  while (len-- > 0) {
    rc4_u8 a = array[++i];
    rc4_u8 b = array[j += a];

    array[i] = b;
    array[j] = a;

    *buf++ ^= array[(a + b) & 255];
  }

  state->rc4_i = i;
  state->rc4_j = j;
}

#ifdef RC4_TESTING

rc4_u8 key_0[] = { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef};
rc4_u8 input_0[] = { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef };
rc4_u8 output_0[] = { 0x75, 0xb7, 0x87, 0x80, 0x99, 0xe0, 0xc5, 0x96 };

rc4_u8 key_1[] = { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, };
rc4_u8 input_1[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, };
rc4_u8 output_1[] = { 0x74, 0x94, 0xc2, 0xe7, 0x10, 0x4b, 0x08, 0x79, };

rc4_u8 key_2[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, };
rc4_u8 input_2[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, };
rc4_u8 output_2[] = { 0xde, 0x18, 0x89, 0x41, 0xa3, 0x37, 0x5d, 0x3a, };

rc4_u8 key_3[] = { 0xef, 0x01, 0x23, 0x45, };
rc4_u8 input_3[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, };
rc4_u8 output_3[] = { 0xd6, 0xa1, 0x41, 0xa7, 0xec, 0x3c, 0x38, 0xdf, 0xbd, 0x61, };
rc4_u8 key_4[] = { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, };
rc4_u8 input_4[] = {
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
  0x01, };

rc4_u8 output_4[] = {
  0x75, 0x95, 0xc3, 0xe6, 0x11, 0x4a, 0x09, 0x78, 0x0c, 0x4a, 0xd4,
  0x52, 0x33, 0x8e, 0x1f, 0xfd, 0x9a, 0x1b, 0xe9, 0x49, 0x8f,
  0x81, 0x3d, 0x76, 0x53, 0x34, 0x49, 0xb6, 0x77, 0x8d, 0xca,
  0xd8, 0xc7, 0x8a, 0x8d, 0x2b, 0xa9, 0xac, 0x66, 0x08, 0x5d,
  0x0e, 0x53, 0xd5, 0x9c, 0x26, 0xc2, 0xd1, 0xc4, 0x90, 0xc1,
  0xeb, 0xbe, 0x0c, 0xe6, 0x6d, 0x1b, 0x6b, 0x1b, 0x13, 0xb6,
  0xb9, 0x19, 0xb8, 0x47, 0xc2, 0x5a, 0x91, 0x44, 0x7a, 0x95,
  0xe7, 0x5e, 0x4e, 0xf1, 0x67, 0x79, 0xcd, 0xe8, 0xbf, 0x0a,
  0x95, 0x85, 0x0e, 0x32, 0xaf, 0x96, 0x89, 0x44, 0x4f, 0xd3,
  0x77, 0x10, 0x8f, 0x98, 0xfd, 0xcb, 0xd4, 0xe7, 0x26, 0x56,
  0x75, 0x00, 0x99, 0x0b, 0xcc, 0x7e, 0x0c, 0xa3, 0xc4, 0xaa,
  0xa3, 0x04, 0xa3, 0x87, 0xd2, 0x0f, 0x3b, 0x8f, 0xbb, 0xcd,
  0x42, 0xa1, 0xbd, 0x31, 0x1d, 0x7a, 0x43, 0x03, 0xdd, 0xa5,
  0xab, 0x07, 0x88, 0x96, 0xae, 0x80, 0xc1, 0x8b, 0x0a, 0xf6,
  0x6d, 0xff, 0x31, 0x96, 0x16, 0xeb, 0x78, 0x4e, 0x49, 0x5a,
  0xd2, 0xce, 0x90, 0xd7, 0xf7, 0x72, 0xa8, 0x17, 0x47, 0xb6,
  0x5f, 0x62, 0x09, 0x3b, 0x1e, 0x0d, 0xb9, 0xe5, 0xba, 0x53,
  0x2f, 0xaf, 0xec, 0x47, 0x50, 0x83, 0x23, 0xe6, 0x71, 0x32,
  0x7d, 0xf9, 0x44, 0x44, 0x32, 0xcb, 0x73, 0x67, 0xce, 0xc8,
  0x2f, 0x5d, 0x44, 0xc0, 0xd0, 0x0b, 0x67, 0xd6, 0x50, 0xa0,
  0x75, 0xcd, 0x4b, 0x70, 0xde, 0xdd, 0x77, 0xeb, 0x9b, 0x10,
  0x23, 0x1b, 0x6b, 0x5b, 0x74, 0x13, 0x47, 0x39, 0x6d, 0x62,
  0x89, 0x74, 0x21, 0xd4, 0x3d, 0xf9, 0xb4, 0x2e, 0x44, 0x6e,
  0x35, 0x8e, 0x9c, 0x11, 0xa9, 0xb2, 0x18, 0x4e, 0xcb, 0xef,
  0x0c, 0xd8, 0xe7, 0xa8, 0x77, 0xef, 0x96, 0x8f, 0x13, 0x90,
  0xec, 0x9b, 0x3d, 0x35, 0xa5, 0x58, 0x5c, 0xb0, 0x09, 0x29,
  0x0e, 0x2f, 0xcd, 0xe7, 0xb5, 0xec, 0x66, 0xd9, 0x08, 0x4b,
  0xe4, 0x40, 0x55, 0xa6, 0x19, 0xd9, 0xdd, 0x7f, 0xc3, 0x16,
  0x6f, 0x94, 0x87, 0xf7, 0xcb, 0x27, 0x29, 0x12, 0x42, 0x64,
  0x45, 0x99, 0x85, 0x14, 0xc1, 0x5d, 0x53, 0xa1, 0x8c, 0x86,
  0x4c, 0xe3, 0xa2, 0xb7, 0x55, 0x57, 0x93, 0x98, 0x81, 0x26,
  0x52, 0x0e, 0xac, 0xf2, 0xe3, 0x06, 0x6e, 0x23, 0x0c, 0x91,
  0xbe, 0xe4, 0xdd, 0x53, 0x04, 0xf5, 0xfd, 0x04, 0x05, 0xb3,
  0x5b, 0xd9, 0x9c, 0x73, 0x13, 0x5d, 0x3d, 0x9b, 0xc3, 0x35,
  0xee, 0x04, 0x9e, 0xf6, 0x9b, 0x38, 0x67, 0xbf, 0x2d, 0x7b,
  0xd1, 0xea, 0xa5, 0x95, 0xd8, 0xbf, 0xc0, 0x06, 0x6f, 0xf8,
  0xd3, 0x15, 0x09, 0xeb, 0x0c, 0x6c, 0xaa, 0x00, 0x6c, 0x80,
  0x7a, 0x62, 0x3e, 0xf8, 0x4c, 0x3d, 0x33, 0xc1, 0x95, 0xd2,
  0x3e, 0xe3, 0x20, 0xc4, 0x0d, 0xe0, 0x55, 0x81, 0x57, 0xc8,
  0x22, 0xd4, 0xb8, 0xc5, 0x69, 0xd8, 0x49, 0xae, 0xd5, 0x9d,
  0x4e, 0x0f, 0xd7, 0xf3, 0x79, 0x58, 0x6b, 0x4b, 0x7f, 0xf6,
  0x84, 0xed, 0x6a, 0x18, 0x9f, 0x74, 0x86, 0xd4, 0x9b, 0x9c,
  0x4b, 0xad, 0x9b, 0xa2, 0x4b, 0x96, 0xab, 0xf9, 0x24, 0x37,
  0x2c, 0x8a, 0x8f, 0xff, 0xb1, 0x0d, 0x55, 0x35, 0x49, 0x00,
  0xa7, 0x7a, 0x3d, 0xb5, 0xf2, 0x05, 0xe1, 0xb9, 0x9f, 0xcd,
  0x86, 0x60, 0x86, 0x3a, 0x15, 0x9a, 0xd4, 0xab, 0xe4, 0x0f,
  0xa4, 0x89, 0x34, 0x16, 0x3d, 0xdd, 0xe5, 0x42, 0xa6, 0x58,
  0x55, 0x40, 0xfd, 0x68, 0x3c, 0xbf, 0xd8, 0xc0, 0x0f, 0x12,
  0x12, 0x9a, 0x28, 0x4d, 0xea, 0xcc, 0x4c, 0xde, 0xfe, 0x58,
  0xbe, 0x71, 0x37, 0x54, 0x1c, 0x04, 0x71, 0x26, 0xc8, 0xd4,
  0x9e, 0x27, 0x55, 0xab, 0x18, 0x1a, 0xb7, 0xe9, 0x40, 0xb0,
  0xc0, };

#include <stdio.h>

void printout(const char *title, rc4_u8 *data, int len) {
  int i;

  puts(title);

  for (i = 0; i < len; i++) {
    printf("0x%02x ", data[i]);
  }

  putchar('\n');
}

int main() {
  int failed = 0;

  rc4_t state[1];

  rc4_init(key_0, sizeof key_0, state);
  rc4(input_0, sizeof input_0, state);
  if (memcmp(input_0, output_0, sizeof input_0)) {
    printout("Test 0 output", input_0, sizeof input_0);
    failed = 1;
  }

  if (!failed) {
    puts("RC4 seems to work\n");
  }

  rc4_prepare_key(key_1, sizeof key_1, state);
  rc4(input_1, sizeof input_1, state);
  if (memcmp(input_1, output_1, sizeof input_1)) {
    printout("Test 1 output", input_1, sizeof input_1);
    failed = 1;
  }

  rc4_prepare_key(key_2, sizeof key_2, state);
  rc4(input_2, sizeof input_2, state);
  if (memcmp(input_2, output_2, sizeof input_2)) {
    printout("Test 2 output", input_2, sizeof input_2);
    failed = 1;
  }

  rc4_prepare_key(key_3, sizeof key_3, state);
  rc4(input_3, sizeof input_3, state);
  if (memcmp(input_3, output_3, sizeof input_3)) {
    printout("Test 3 output", input_3, sizeof input_3);
    failed = 1;
  }

  rc4_prepare_key(key_4, sizeof key_4, state);
  rc4(input_4, sizeof input_4, state);
  if (memcmp(input_4, output_4, sizeof input_4)) {
    printout("Test 4 output", input_4, sizeof input_4);
    failed = 1;
  }

  exit(failed);
}

#endif