wargame/vortex
vortex5
Sanguine
2014. 6. 8. 22:44
Vortex Level 5 → Level 6
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.
Included file: vortex5.c
/* 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);
}코드가 길다.
그냥 메인보면, MD5 값을 찾아야 하는거다.
머 요즘은 인터넷에 MD5 bruteforce해주는곳이 많아서 해보면 쉽게 비번을 찾을수 있지만, 워게임이니 코딩해서 해결하기로 했다.
비밀번호 조건은 A-Z,a-z,0-9만 썻다고 한다. 그리고 5글자에서 7글자라고 한다.
다음은 내가 코딩한 소스이다.
위에 소스에서 MD5해주는 부분을 그대로 가져다 써서, 고친 메인함수만 올리겠다.
int main(int argc, char **argv)
{unsigned char buf[16];
MD5Context a;char cmp_str[6];
char search_code[100]="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
int i,j,k,l,m;
clock_t start_time, end_time; // clock_t
start_time = clock(); // Start_Time
cmp_str[5]=NULL;
for(i=0;i<strlen(search_code);i++){
for(j=0;j<strlen(search_code);j++){
for(k=0;k<strlen(search_code);k++){
for(l=0;l<strlen(search_code);l++){
for(m=0;m<strlen(search_code);m++){
cmp_str[0]=search_code[i];
cmp_str[1]=search_code[j];
cmp_str[2]=search_code[k];
cmp_str[3]=search_code[l];
cmp_str[4]=search_code[m];
MD5Init(&a);
MD5Update(&a, cmp_str, strlen(cmp_str));
MD5Final(buf, &a);
if(memcmp(buf, "\x15\x5f\xb9\x5d\x04\x28\x7b\x75\x7c\x99\x6d\x77\xb5\xea\x51\xf7", 16) == 0){
end_time=clock();
printf("code:%s\n",cmp_str);
printf("Time : %f\n", ((double)(end_time-start_time)) / CLOCKS_PER_SEC);
exit(0);
} } } } } }}
vortex5@melinda:/tmp/Sanguine3$ ./vortex5
code:rlTf6
Time : 389.960000
vortex5@melinda:/tmp/Sanguine3$ cd /games/vortex
vortex5@melinda:/games/vortex$ ./vortex5
Password:
6:36
You got the right password, congrats!
$ cat /etc/vortex_pass/vortex6
*uy5qDRb2