Reversing challenge 300 from hack.lu 2014.

5 files changed, 1111 insertions, 0 deletions

diff --git a/src/desCalculator/COPYING.LIB b/src/desCalculator/COPYING.LIB
new file mode 100644
index 0000000..cf9b6b9
--- /dev/null
+++ b/src/desCalculator/COPYING.LIB
@@ -0,0 +1,510 @@
+
+                  GNU LESSER GENERAL PUBLIC LICENSE
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diff --git a/src/desCalculator/README b/src/desCalculator/README
new file mode 100644
index 0000000..5280a0d
--- /dev/null
+++ b/src/desCalculator/README
@@ -0,0 +1,28 @@
+Libmcrypt is a thread-safe library providing a uniform interface
+to access several block and stream encryption algorithms.
+Check the manual page for more information on libmcrypt.
+
+Look at COPYING for license information and the individual files for more 
+information. COPYING applies only for the mcrypt program and not the 
+algorithms which most of them are public domain.
+
+A mailing list on mcrypt is mcrypt-dev@lists.hellug.gr
+Subscribe by visiting http://lists.hellug.gr/mailman/listinfo/mcrypt-dev
+
+**
+** Some hints:
+
+Since 2.5.4 libmcrypt does not use dynamic loading for the modules by default.
+All the algorithms and modes, are now included in the library. To enable
+the old dynamic loading behaviour use the --enable-dynamic-loading in the
+configure script.
+
+That way you can statically link the library and be 100% thread safe,
+since dlopen is not always thread safe.
+
+You can also enable dynamic loading and include some algorithms into the
+library. To include algorithms in the library use the
+--with-included-algos parameter in the configure script.
+Eg: ./configure --with-included-algos="rijndael-128 arcfour stream cbc cfb"
+
+
diff --git a/src/desCalculator/des.c b/src/desCalculator/des.c
new file mode 100644
index 0000000..d9de167
--- /dev/null
+++ b/src/desCalculator/des.c
@@ -0,0 +1,494 @@
+
+/* Sofware DES functions
+ * written 12 Dec 1986 by Phil Karn, KA9Q; large sections adapted from
+ * the 1977 public-domain program by Jim Gillogly
+ * Modified for additional speed - 6 December 1988 Phil Karn
+ * Modified for parameterized key schedules - Jan 1991 Phil Karn
+ * Callers now allocate a key schedule as follows:
+ *	kn = (char (*)[8])malloc(sizeof(char) * 8 * 16);
+ *	or
+ *	char kn[16][8];
+ */
+
+/* modified in order to use the libmcrypt API by Nikos Mavroyanopoulos 
+ * All modifications are placed under the license of libmcrypt.
+ */
+
+/* $Id: des.c,v 1.13 2003/01/19 17:48:27 nmav Exp $ */
+
+#include "des.h"
+
+/* #define	NULL	0 */
+
+static void permute_ip(), permute_fp(), perminit_ip(), spinit(),
+perminit_fp();
+static uint32_t f();
+
+
+/* Tables defined in the Data Encryption Standard documents */
+
+/* initial permutation IP */
+static char ip[] = {
+	58, 50, 42, 34, 26, 18, 10, 2,
+	60, 52, 44, 36, 28, 20, 12, 4,
+	62, 54, 46, 38, 30, 22, 14, 6,
+	64, 56, 48, 40, 32, 24, 16, 8,
+	57, 49, 41, 33, 25, 17, 9, 1,
+	59, 51, 43, 35, 27, 19, 11, 3,
+	61, 53, 45, 37, 29, 21, 13, 5,
+	63, 55, 47, 39, 31, 23, 15, 7
+};
+
+/* final permutation IP^-1 */
+static char fp[] = {
+	40, 8, 48, 16, 56, 24, 64, 32,
+	39, 7, 47, 15, 55, 23, 63, 31,
+	38, 6, 46, 14, 54, 22, 62, 30,
+	37, 5, 45, 13, 53, 21, 61, 29,
+	36, 4, 44, 12, 52, 20, 60, 28,
+	35, 3, 43, 11, 51, 19, 59, 27,
+	34, 2, 42, 10, 50, 18, 58, 26,
+	33, 1, 41, 9, 49, 17, 57, 25
+};
+
+/* expansion operation matrix
+ * This is for reference only; it is unused in the code
+ * as the f() function performs it implicitly for speed
+ */
+#ifdef notdef
+static char ei[] = {
+	32, 1, 2, 3, 4, 5,
+	4, 5, 6, 7, 8, 9,
+	8, 9, 10, 11, 12, 13,
+	12, 13, 14, 15, 16, 17,
+	16, 17, 18, 19, 20, 21,
+	20, 21, 22, 23, 24, 25,
+	24, 25, 26, 27, 28, 29,
+	28, 29, 30, 31, 32, 1
+};
+#endif
+
+/* permuted choice table (key) */
+static char pc1[] = {
+	57, 49, 41, 33, 25, 17, 9,
+	1, 58, 50, 42, 34, 26, 18,
+	10, 2, 59, 51, 43, 35, 27,
+	19, 11, 3, 60, 52, 44, 36,
+
+	63, 55, 47, 39, 31, 23, 15,
+	7, 62, 54, 46, 38, 30, 22,
+	14, 6, 61, 53, 45, 37, 29,
+	21, 13, 5, 28, 20, 12, 4
+};
+
+/* number left rotations of pc1 */
+static char totrot[] = {
+	1, 2, 4, 6, 8, 10, 12, 14, 15, 17, 19, 21, 23, 25, 27, 28
+};
+
+/* permuted choice key (table) */
+static char pc2[] = {
+	14, 17, 11, 24, 1, 5,
+	3, 28, 15, 6, 21, 10,
+	23, 19, 12, 4, 26, 8,
+	16, 7, 27, 20, 13, 2,
+	41, 52, 31, 37, 47, 55,
+	30, 40, 51, 45, 33, 48,
+	44, 49, 39, 56, 34, 53,
+	46, 42, 50, 36, 29, 32
+};
+
+/* The (in)famous S-boxes */
+static char si[8][64] = {
+	/* S1 */
+	{14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7,
+	 0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8,
+	 4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0,
+	 15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13},
+
+	/* S2 */
+	{15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10,
+	 3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5,
+	 0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15,
+	 13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9},
+
+	/* S3 */
+	{10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8,
+	 13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1,
+	 13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7,
+	 1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12},
+
+	/* S4 */
+	{7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15,
+	 13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9,
+	 10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4,
+	 3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14},
+
+	/* S5 */
+	{2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9,
+	 14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6,
+	 4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14,
+	 11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3},
+
+	/* S6 */
+	{12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11,
+	 10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8,
+	 9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6,
+	 4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13},
+
+	/* S7 */
+	{4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1,
+	 13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6,
+	 1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2,
+	 6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12},
+
+	/* S8 */
+	{13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7,
+	 1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2,
+	 7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8,
+	 2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11},
+
+};
+
+/* 32-bit permutation function P used on the output of the S-boxes */
+static char p32i[] = {
+	16, 7, 20, 21,
+	29, 12, 28, 17,
+	1, 15, 23, 26,
+	5, 18, 31, 10,
+	2, 8, 24, 14,
+	32, 27, 3, 9,
+	19, 13, 30, 6,
+	22, 11, 4, 25
+};
+
+/* End of DES-defined tables */
+
+/* Lookup tables initialized once only at startup by desinit() */
+
+/* bit 0 is left-most in byte */
+static int bytebit[] = {
+	0200, 0100, 040, 020, 010, 04, 02, 01
+};
+
+static int nibblebit[] = {
+	010, 04, 02, 01
+};
+
+/* Allocate space and initialize DES lookup arrays
+ * mode == 0: standard Data Encryption Algorithm
+ */
+static int _mcrypt_desinit(DES_KEY * key)
+{
+
+	spinit(key);
+	perminit_ip(key);
+	perminit_fp(key);
+
+	return 0;
+}
+
+
+/* Set key (initialize key schedule array) */
+int _mcrypt_set_key(DES_KEY * dkey, char *user_key, int len)
+{
+	char pc1m[56];		/* place to modify pc1 into */
+	char pcr[56];		/* place to rotate pc1 into */
+	register int i, j, l;
+	int m;
+
+	Bzero(dkey, sizeof(DES_KEY));
+	_mcrypt_desinit(dkey);
+
+	/* Clear key schedule */
+
+
+	for (j = 0; j < 56; j++) {	/* convert pc1 to bits of key */
+		l = pc1[j] - 1;	/* integer bit location  */
+		m = l & 07;	/* find bit              */
+		pc1m[j] = (user_key[l >> 3] &	/* find which key byte l is in */
+			   bytebit[m])	/* and which bit of that byte */
+		    ? 1 : 0;	/* and store 1-bit result */
+
+	}
+	for (i = 0; i < 16; i++) {	/* key chunk for each iteration */
+		for (j = 0; j < 56; j++)	/* rotate pc1 the right amount */
+			pcr[j] =
+			    pc1m[(l = j + totrot[i]) <
+				 (j < 28 ? 28 : 56) ? l : l - 28];
+		/* rotate left and right halves independently */
+		for (j = 0; j < 48; j++) {	/* select bits individually */
+			/* check bit that goes to kn[j] */
+			if (pcr[pc2[j] - 1]) {
+				/* mask it in if it's there */
+				l = j % 6;
+				dkey->kn[i][j / 6] |= bytebit[l] >> 2;
+			}
+		}
+	}
+	return 0;
+}
+
+/* In-place encryption of 64-bit block */
+void _mcrypt_encrypt(DES_KEY * key, char *block)
+{
+	uint32_t strings[20];
+
+	register uint32_t left, right;
+	register char *knp;
+	uint32_t work[2];		/* Working data storage */
+
+	strings[0] = 0x8080CAA3;
+	permute_ip(block, key, (char *) work);	/* Initial Permutation */
+#ifndef	WORDS_BIGENDIAN
+	left = byteswap32(work[0]);
+	right = byteswap32(work[1]);
+#else
+	left = work[0];
+	right = work[1];
+#endif
+
+	strings[1] = 0x83F5EF93;
+	/* Do the 16 rounds.
+	 * The rounds are numbered from 0 to 15. On even rounds
+	 * the right half is fed to f() and the result exclusive-ORs
+	 * the left half; on odd rounds the reverse is done.
+	 */
+	knp = &key->kn[0][0];
+	strings[3] = 0xF5C58BFF;
+	left ^= f(key, right, knp);
+	knp += 8;
+	strings[2] = 0xE5EF9A9C;
+	right ^= f(key, left, knp);
+	printf("des_intermediate_value = [0x%X, 0x%X]\n", left, right);
+	knp += 8;
+	left ^= f(key, right, knp);
+	knp += 8;
+	right ^= f(key, left, knp);
+	knp += 8;
+	left ^= f(key, right, knp);
+	knp += 8;
+	right ^= f(key, left, knp);
+	knp += 8;
+	left ^= f(key, right, knp);
+	knp += 8;
+	right ^= f(key, left, knp);
+	knp += 8;
+	left ^= f(key, right, knp);
+	knp += 8;
+	right ^= f(key, left, knp);
+	knp += 8;
+	left ^= f(key, right, knp);
+	knp += 8;
+	right ^= f(key, left, knp);
+	knp += 8;
+	left ^= f(key, right, knp);
+	knp += 8;
+	right ^= f(key, left, knp);
+	knp += 8;
+	left ^= f(key, right, knp);
+	knp += 8;
+	right ^= f(key, left, knp);
+
+	/* Left/right half swap, plus byte swap if little-endian */
+#ifndef	WORDS_BIGENDIAN
+	work[1] = byteswap32(left);
+	work[0] = byteswap32(right);
+#else
+	work[0] = right;
+	work[1] = left;
+#endif
+	permute_fp((char *) work, key, block);	/* Inverse initial permutation */
+}
+
+/* Permute inblock with perm */
+static void permute_ip(char *inblock, DES_KEY * key, char *outblock)
+{
+	register char *ib, *ob;	/* ptr to input or output block */
+	register char *p, *q;
+	register int j;
+
+	/* Clear output block */
+	Bzero(outblock, 8);
+
+	ib = inblock;
+	for (j = 0; j < 16; j += 2, ib++) {	/* for each input nibble */
+		ob = outblock;
+		p = key->iperm[j][(*ib >> 4) & 0xf];
+		q = key->iperm[j + 1][*ib & 0xf];
+		/* and each output byte, OR the masks together */
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+	}
+}
+
+/* Permute inblock with perm */
+static void permute_fp(char *inblock, DES_KEY * key, char *outblock)
+{
+	register char *ib, *ob;	/* ptr to input or output block */
+	register char *p, *q;
+	register int j;
+
+	/* Clear output block */
+	Bzero(outblock, 8);
+
+	ib = inblock;
+	for (j = 0; j < 16; j += 2, ib++) {	/* for each input nibble */
+		ob = outblock;
+		p = key->fperm[j][(*ib >> 4) & 0xf];
+		q = key->fperm[j + 1][*ib & 0xf];
+		/* and each output byte, OR the masks together */
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+		*ob++ |= *p++ | *q++;
+	}
+}
+
+/* The nonlinear function f(r,k), the heart of DES */
+static uint32_t f(DES_KEY * key, register uint32_t r, register char *subkey)
+{
+	register uint32_t *spp;
+	register uint32_t rval, rt;
+	register int er;
+
+#ifdef	TRACE
+	printf("f(%08lx, %02x %02x %02x %02x %02x %02x %02x %02x) = ",
+	       r,
+	       subkey[0], subkey[1], subkey[2],
+	       subkey[3], subkey[4], subkey[5], subkey[6], subkey[7]);
+#endif
+	/* Run E(R) ^ K through the combined S & P boxes.
+	 * This code takes advantage of a convenient regularity in
+	 * E, namely that each group of 6 bits in E(R) feeding
+	 * a single S-box is a contiguous segment of R.
+	 */
+	subkey += 7;
+
+	/* Compute E(R) for each block of 6 bits, and run thru boxes */
+	er = ((int) r << 1) | ((r & 0x80000000) ? 1 : 0);
+	spp = &key->sp[7][0];
+	rval = spp[(er ^ *subkey--) & 0x3f];
+	spp -= 64;
+	rt = (uint32_t) r >> 3;
+	rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+	spp -= 64;
+	rt >>= 4;
+	rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+	spp -= 64;
+	rt >>= 4;
+	rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+	spp -= 64;
+	rt >>= 4;
+	rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+	spp -= 64;
+	rt >>= 4;
+	rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+	spp -= 64;
+	rt >>= 4;
+	rval |= spp[((int) rt ^ *subkey--) & 0x3f];
+	spp -= 64;
+	rt >>= 4;
+	rt |= (r & 1) << 5;
+	rval |= spp[((int) rt ^ *subkey) & 0x3f];
+#ifdef	TRACE
+	printf(" %08lx\n", rval);
+#endif
+	return rval;
+}
+
+/* initialize a perm array */
+static void perminit_ip(DES_KEY * key)
+{
+	register int l, j, k;
+	int i, m;
+
+	/* Clear the permutation array */
+	Bzero(key->iperm, 16 * 16 * 8);
+
+	for (i = 0; i < 16; i++)	/* each input nibble position */
+		for (j = 0; j < 16; j++)	/* each possible input nibble */
+			for (k = 0; k < 64; k++) {	/* each output bit position */
+				l = ip[k] - 1;	/* where does this bit come from */
+				if ((l >> 2) != i)	/* does it come from input posn? */
+					continue;	/* if not, bit k is 0    */
+				if (!(j & nibblebit[l & 3]))
+					continue;	/* any such bit in input? */
+				m = k & 07;	/* which bit is this in the byte */
+				key->iperm[i][j][k >> 3] |= bytebit[m];
+			}
+}
+
+static void perminit_fp(DES_KEY * key)
+{
+	register int l, j, k;
+	int i, m;
+
+	/* Clear the permutation array */
+	Bzero(key->fperm, 16 * 16 * 8);
+
+	for (i = 0; i < 16; i++)	/* each input nibble position */
+		for (j = 0; j < 16; j++)	/* each possible input nibble */
+			for (k = 0; k < 64; k++) {	/* each output bit position */
+				l = fp[k] - 1;	/* where does this bit come from */
+				if ((l >> 2) != i)	/* does it come from input posn? */
+					continue;	/* if not, bit k is 0    */
+				if (!(j & nibblebit[l & 3]))
+					continue;	/* any such bit in input? */
+				m = k & 07;	/* which bit is this in the byte */
+				key->fperm[i][j][k >> 3] |= bytebit[m];
+			}
+}
+
+/* Initialize the lookup table for the combined S and P boxes */
+static void spinit(DES_KEY * key)
+{
+	char pbox[32];
+	int p, i, s, j, rowcol;
+	uint32_t val;
+
+	/* Compute pbox, the inverse of p32i.
+	 * This is easier to work with
+	 */
+	for (p = 0; p < 32; p++) {
+		for (i = 0; i < 32; i++) {
+			if (p32i[i] - 1 == p) {
+				pbox[p] = i;
+				break;
+			}
+		}
+	}
+	for (s = 0; s < 8; s++) {	/* For each S-box */
+		for (i = 0; i < 64; i++) {	/* For each possible input */
+			val = 0;
+			/* The row number is formed from the first and last
+			 * bits; the column number is from the middle 4
+			 */
+			rowcol =
+			    (i & 32) | ((i & 1) ? 16 : 0) | ((i >> 1) &
+							     0xf);
+			for (j = 0; j < 4; j++) {	/* For each output bit */
+				if (si[s][rowcol] & (8 >> j)) {
+					val |=
+					    1L << (31 - pbox[4 * s + j]);
+				}
+			}
+			key->sp[s][i] = val;
+
+#ifdef DEBUG
+			printf("sp[%d][%2d] = %08lx\n", s, i,
+			       key->sp[s][i]);
+#endif
+		}
+	}
+}
diff --git a/src/desCalculator/des.h b/src/desCalculator/des.h
new file mode 100644
index 0000000..a861f2a
--- /dev/null
+++ b/src/desCalculator/des.h
@@ -0,0 +1,25 @@
+#include <stdint.h>
+#include <string.h>
+#include <stdio.h>
+
+#ifndef DES_H
+#define DES_H
+
+#define rotl32(x,n)   (((x) << ((uint32_t)(n))) | ((x) >> (32 - (uint32_t)(n))))
+#define rotr32(x,n)   (((x) >> ((uint32_t)(n))) | ((x) << (32 - (uint32_t)(n))))
+
+#define byteswap32(x)	((rotl32(x, 8) & 0x00ff00ff) | (rotr32(x, 8) & 0xff00ff00))
+
+#define Bzero(x, y) memset(x, 0, y)
+
+typedef struct des_key {
+	char kn[16][8];
+	uint32_t sp[8][64];
+	char iperm[16][16][8];
+	char fperm[16][16][8];
+} DES_KEY;
+
+int _mcrypt_set_key(DES_KEY * dkey, char *user_key, int len);
+void _mcrypt_encrypt(DES_KEY * key, char *block);
+
+#endif
\ No newline at end of file
diff --git a/src/desCalculator/desCalculator.c b/src/desCalculator/desCalculator.c
new file mode 100644
index 0000000..a6f1dba
--- /dev/null
+++ b/src/desCalculator/desCalculator.c
@@ -0,0 +1,54 @@
+#include <stdio.h>

+#include <stdint.h>

+#include "des.h"

+

+int main()

+{

+	char *keyword;

+	unsigned char plaintext[16];

+	unsigned char ciphertext[16];

+	int j;

+	DES_KEY key;

+	uint32_t AddressOfEntryPoint = 0x00002140;

+

+	keyword = (char *)calloc(8, 1);

+	if (keyword == NULL)

+		return -1;

+

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

+		// The key goes here

+		keyword[j] = '\x7f';

+	}

+

+	*(uint32_t *)keyword ^= 0x41424344;

+	*((uint32_t *)keyword + 1) ^= AddressOfEntryPoint;

+

+	/* Authentication: DEAD696E18791211 => 0xDEAD in 0x1879 0x1 ! 0x1 */

+	plaintext[0] = '\xDE';

+	plaintext[1] = '\xAD';

+	plaintext[2] = '\x69';

+	plaintext[3] = '\x6E';

+	plaintext[4] = '\x18';

+	plaintext[5] = '\x79';

+	plaintext[6] = '\x12';

+	plaintext[7] = '\x11';

+

+	memcpy(ciphertext, plaintext, 8);

+

+	_mcrypt_set_key(&key, (void *) keyword, 8);

+	free(keyword);

+

+	_mcrypt_encrypt(&key, (void *) ciphertext);

+

+

+	printf("des_output_value = [0x%02X",ciphertext[3]);

+	printf("%02X",ciphertext[2]);

+	printf("%02X",ciphertext[1]);

+	printf("%02X, ",ciphertext[0]);

+	printf("0x%02X",ciphertext[7]);

+	printf("%02X",ciphertext[6]);

+	printf("%02X",ciphertext[5]);

+	printf("%02X]",ciphertext[4]);

+

+	return 0;

+}
\ No newline at end of file