Vortex Level 5

MD5 Brute Force

A password is required for the next level. vortex5.c and md5.h. a-z,A-Z,0-9 is the search space. The password length is 5 chars long, it was originally 7 chars long.

Collision(s) tested : 489265082 in 217 second(s), 361 millisec, 101 microsec. Average of 2250932.1 hashes/sec.

Source code

/* A tribute to arc :) */
/*
** SQLite uses this code for testing only.  It is not a part of
** the SQLite library.  This file implements two new TCL commands
** "md5" and "md5file" that compute md5 checksums on arbitrary text
** and on complete files.  These commands are used by the "testfixture"
** program to help verify the correct operation of the SQLite library.
**
** The original use of these TCL commands was to test the ROLLBACK
** feature of SQLite.  First compute the MD5-checksum of the database.
** Then make some changes but rollback the changes rather than commit
** them.  Compute a second MD5-checksum of the file and verify that the
** two checksums are the same.  Such is the original use of this code.
** New uses may have been added since this comment was written.
*/
/*
 * This code implements the MD5 message-digest algorithm.
 * The algorithm is due to Ron Rivest.  This code was
 * written by Colin Plumb in 1993, no copyright is claimed.
 * This code is in the public domain; do with it what you wish.
 *
 * Equivalent code is available from RSA Data Security, Inc.
 * This code has been tested against that, and is equivalent,
 * except that you don't need to include two pages of legalese
 * with every copy.
 *
 * To compute the message digest of a chunk of bytes, declare an
 * MD5Context structure, pass it to MD5Init, call MD5Update as
 * needed on buffers full of bytes, and then call MD5Final, which
 * will fill a supplied 16-byte array with the digest.
 */

/*
 * If compiled on a machine that doesn't have a 32-bit integer,
 * you just set "uint32" to the appropriate datatype for an
 * unsigned 32-bit integer.  For example:
 *
 *   cc -Duint32='unsigned long' md5.c
 *
 */
#ifndef uint32
#  define uint32 unsigned int
#endif

struct Context {
  uint32 buf[4];
  uint32 bits[2];
  unsigned char in[64];
};

typedef char MD5Context[88];

/*
 * Note: this code is harmless on little-endian machines.
 */
static void byteReverse (unsigned char *buf, unsigned longs){
  uint32 t;
  do {
    t = (uint32)((unsigned)buf[3]<<8 | buf[2]) << 16 |
        ((unsigned)buf[1]<<8 | buf[0]);
    *(uint32 *)buf = t;
    buf += 4;
  } while (--longs);
}

/* The four core functions - F1 is optimized somewhat */

/* #define F1(x, y, z) (x & y | ~x & z) */
#define F1(x, y, z) (z ^ (x & (y ^ z)))
#define F2(x, y, z) F1(z, x, y)
#define F3(x, y, z) (x ^ y ^ z)
#define F4(x, y, z) (y ^ (x | ~z))

/* This is the central step in the MD5 algorithm. */
#define MD5STEP(f, w, x, y, z, data, s) \
        ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x )

/*
 * The core of the MD5 algorithm, this alters an existing MD5 hash to
 * reflect the addition of 16 longwords of new data.  MD5Update blocks
 * the data and converts bytes into longwords for this routine.
 */
static void MD5Transform(uint32 buf[4], const uint32 in[16]){
  register uint32 a, b, c, d;

  a = buf[0];
  b = buf[1];
  c = buf[2];
  d = buf[3];

  MD5STEP(F1, a, b, c, d, in[ 0]+0xd76aa478, 7);
  MD5STEP(F1, d, a, b, c, in[ 1]+0xe8c7b756, 12);
  MD5STEP(F1, c, d, a, b, in[ 2]+0x242070db, 17);
  MD5STEP(F1, b, c, d, a, in[ 3]+0xc1bdceee, 22);
  MD5STEP(F1, a, b, c, d, in[ 4]+0xf57c0faf, 7);
  MD5STEP(F1, d, a, b, c, in[ 5]+0x4787c62a, 12);
  MD5STEP(F1, c, d, a, b, in[ 6]+0xa8304613, 17);
  MD5STEP(F1, b, c, d, a, in[ 7]+0xfd469501, 22);
  MD5STEP(F1, a, b, c, d, in[ 8]+0x698098d8, 7);
  MD5STEP(F1, d, a, b, c, in[ 9]+0x8b44f7af, 12);
  MD5STEP(F1, c, d, a, b, in[10]+0xffff5bb1, 17);
  MD5STEP(F1, b, c, d, a, in[11]+0x895cd7be, 22);
  MD5STEP(F1, a, b, c, d, in[12]+0x6b901122, 7);
  MD5STEP(F1, d, a, b, c, in[13]+0xfd987193, 12);
  MD5STEP(F1, c, d, a, b, in[14]+0xa679438e, 17);
  MD5STEP(F1, b, c, d, a, in[15]+0x49b40821, 22);

  MD5STEP(F2, a, b, c, d, in[ 1]+0xf61e2562, 5);
  MD5STEP(F2, d, a, b, c, in[ 6]+0xc040b340, 9);
  MD5STEP(F2, c, d, a, b, in[11]+0x265e5a51, 14);
  MD5STEP(F2, b, c, d, a, in[ 0]+0xe9b6c7aa, 20);
  MD5STEP(F2, a, b, c, d, in[ 5]+0xd62f105d, 5);
  MD5STEP(F2, d, a, b, c, in[10]+0x02441453, 9);
  MD5STEP(F2, c, d, a, b, in[15]+0xd8a1e681, 14);
  MD5STEP(F2, b, c, d, a, in[ 4]+0xe7d3fbc8, 20);
  MD5STEP(F2, a, b, c, d, in[ 9]+0x21e1cde6, 5);
  MD5STEP(F2, d, a, b, c, in[14]+0xc33707d6, 9);
  MD5STEP(F2, c, d, a, b, in[ 3]+0xf4d50d87, 14);
  MD5STEP(F2, b, c, d, a, in[ 8]+0x455a14ed, 20);
  MD5STEP(F2, a, b, c, d, in[13]+0xa9e3e905, 5);
  MD5STEP(F2, d, a, b, c, in[ 2]+0xfcefa3f8, 9);
  MD5STEP(F2, c, d, a, b, in[ 7]+0x676f02d9, 14);
  MD5STEP(F2, b, c, d, a, in[12]+0x8d2a4c8a, 20);

  MD5STEP(F3, a, b, c, d, in[ 5]+0xfffa3942, 4);
  MD5STEP(F3, d, a, b, c, in[ 8]+0x8771f681, 11);
  MD5STEP(F3, c, d, a, b, in[11]+0x6d9d6122, 16);
  MD5STEP(F3, b, c, d, a, in[14]+0xfde5380c, 23);
  MD5STEP(F3, a, b, c, d, in[ 1]+0xa4beea44, 4);
  MD5STEP(F3, d, a, b, c, in[ 4]+0x4bdecfa9, 11);
  MD5STEP(F3, c, d, a, b, in[ 7]+0xf6bb4b60, 16);
  MD5STEP(F3, b, c, d, a, in[10]+0xbebfbc70, 23);
  MD5STEP(F3, a, b, c, d, in[13]+0x289b7ec6, 4);
  MD5STEP(F3, d, a, b, c, in[ 0]+0xeaa127fa, 11);
  MD5STEP(F3, c, d, a, b, in[ 3]+0xd4ef3085, 16);
  MD5STEP(F3, b, c, d, a, in[ 6]+0x04881d05, 23);
  MD5STEP(F3, a, b, c, d, in[ 9]+0xd9d4d039, 4);
  MD5STEP(F3, d, a, b, c, in[12]+0xe6db99e5, 11);
  MD5STEP(F3, c, d, a, b, in[15]+0x1fa27cf8, 16);
  MD5STEP(F3, b, c, d, a, in[ 2]+0xc4ac5665, 23);

  MD5STEP(F4, a, b, c, d, in[ 0]+0xf4292244, 6);
  MD5STEP(F4, d, a, b, c, in[ 7]+0x432aff97, 10);
  MD5STEP(F4, c, d, a, b, in[14]+0xab9423a7, 15);
  MD5STEP(F4, b, c, d, a, in[ 5]+0xfc93a039, 21);
  MD5STEP(F4, a, b, c, d, in[12]+0x655b59c3, 6);
  MD5STEP(F4, d, a, b, c, in[ 3]+0x8f0ccc92, 10);
  MD5STEP(F4, c, d, a, b, in[10]+0xffeff47d, 15);
  MD5STEP(F4, b, c, d, a, in[ 1]+0x85845dd1, 21);
  MD5STEP(F4, a, b, c, d, in[ 8]+0x6fa87e4f, 6);
  MD5STEP(F4, d, a, b, c, in[15]+0xfe2ce6e0, 10);
  MD5STEP(F4, c, d, a, b, in[ 6]+0xa3014314, 15);
  MD5STEP(F4, b, c, d, a, in[13]+0x4e0811a1, 21);
  MD5STEP(F4, a, b, c, d, in[ 4]+0xf7537e82, 6);
  MD5STEP(F4, d, a, b, c, in[11]+0xbd3af235, 10);
  MD5STEP(F4, c, d, a, b, in[ 2]+0x2ad7d2bb, 15);
  MD5STEP(F4, b, c, d, a, in[ 9]+0xeb86d391, 21);

  buf[0] += a;
  buf[1] += b;
  buf[2] += c;
  buf[3] += d;
}

/*
 * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
 * initialization constants.
 */
static void MD5Init(MD5Context *pCtx){
  struct Context *ctx = (struct Context *)pCtx;
  ctx->buf[0] = 0x67452301;
  ctx->buf[1] = 0xefcdab89;
  ctx->buf[2] = 0x98badcfe;
  ctx->buf[3] = 0x10325476;
  ctx->bits[0] = 0;
  ctx->bits[1] = 0;
}

/*
 * Update context to reflect the concatenation of another buffer full
 * of bytes.
 */
static void MD5Update(MD5Context *pCtx, const unsigned char *buf, unsigned int len){
  struct Context *ctx = (struct Context *)pCtx;
  uint32 t;

  /* Update bitcount */

  t = ctx->bits[0];
  if ((ctx->bits[0] = t + ((uint32)len << 3)) < t)
    ctx->bits[1]++;         /* Carry from low to high */
  ctx->bits[1] += len >> 29;

  t = (t >> 3) & 0x3f;      /* Bytes already in shsInfo->data */

  /* Handle any leading odd-sized chunks */

  if ( t ) {
    unsigned char *p = (unsigned char *)ctx->in + t;

    t = 64-t;
    if (len < t) {
      memcpy(p, buf, len);
      return;
    }
    memcpy(p, buf, t);
    byteReverse(ctx->in, 16);
    MD5Transform(ctx->buf, (uint32 *)ctx->in);
    buf += t;
    len -= t;
  }

  /* Process data in 64-byte chunks */

  while (len >= 64) {
    memcpy(ctx->in, buf, 64);
    byteReverse(ctx->in, 16);
    MD5Transform(ctx->buf, (uint32 *)ctx->in);
    buf += 64;
    len -= 64;
  }

  /* Handle any remaining bytes of data. */

  memcpy(ctx->in, buf, len);
}

/*
 * Final wrapup - pad to 64-byte boundary with the bit pattern
 * 1 0* (64-bit count of bits processed, MSB-first)
 */
static void MD5Final(unsigned char digest[16], MD5Context *pCtx){
  struct Context *ctx = (struct Context *)pCtx;
  unsigned count;
  unsigned char *p;

  /* Compute number of bytes mod 64 */
  count = (ctx->bits[0] >> 3) & 0x3F;

  /* Set the first char of padding to 0x80.  This is safe since there is
     always at least one byte free */
  p = ctx->in + count;
  *p++ = 0x80;

  /* Bytes of padding needed to make 64 bytes */
  count = 64 - 1 - count;

  /* Pad out to 56 mod 64 */
  if (count < 8) {
    /* Two lots of padding:  Pad the first block to 64 bytes */
    memset(p, 0, count);
    byteReverse(ctx->in, 16);
    MD5Transform(ctx->buf, (uint32 *)ctx->in);

    /* Now fill the next block with 56 bytes */
    memset(ctx->in, 0, 56);
  } else {
    /* Pad block to 56 bytes */
    memset(p, 0, count-8);
  }
  byteReverse(ctx->in, 14);

  /* Append length in bits and transform */
  ((uint32 *)ctx->in)[ 14 ] = ctx->bits[0];
  ((uint32 *)ctx->in)[ 15 ] = ctx->bits[1];

  MD5Transform(ctx->buf, (uint32 *)ctx->in);
  byteReverse((unsigned char *)ctx->buf, 4);
  memcpy(digest, ctx->buf, 16);
  memset(ctx, 0, sizeof(ctx));        /* In case it's sensitive */
}

/*
** Convert a digest into base-16.  digest should be declared as
** "unsigned char digest[16]" in the calling function.  The MD5
** digest is stored in the first 16 bytes.  zBuf should
** be "char zBuf[33]".
*/
static void DigestToBase16(unsigned char *digest, char *zBuf){
  static char const zEncode[] = "0123456789abcdef";
  int i, j;

  for(j=i=0; i<16; i++){
    int a = digest[i];
    zBuf[j++] = zEncode[(a>>4)&0xf];
    zBuf[j++] = zEncode[a & 0xf];
  }
  zBuf[j] = 0;
}

int main(int argc, char **argv) {
        unsigned char buf[16];
        MD5Context a;
        char *x;

        x = getpass("Password: ");
        printf("%c:%02x\n", x[strlen(x)-1], x[strlen(x) -1]);
        MD5Init(&a);
        MD5Update(&a, x, strlen(x));
        MD5Final(buf, &a);

        if(memcmp(buf, "\x15\x5f\xb9\x5d\x04\x28\x7b\x75\x7c\x99\x6d\x77\xb5\xea\x51\xf7", 16) == 0){
                printf("You got the right password, congrats!\n");
                setresgid(getegid(), getegid(), getegid());
                setresuid(geteuid(), geteuid(), geteuid());
                system("/bin/sh");
        } else {
                usleep(500);
                printf("Incorrect password\n");
        }
        exit(0);
}