1 files changed, 335 insertions, 0 deletions
diff --git a/src/skey/md4.c b/src/skey/md4.c
new file mode 100644
index 0000000..914f101
--- /dev/null
+++ b/src/skey/md4.c
@@ -0,0 +1,335 @@
+/*
+ *    Copyright (C) 2001 Nikos Mavroyanopoulos
+ *
+ *    This library is free software; you can redistribute it and/or modify it 
+ *    under the terms of the GNU Library General Public License as published 
+ *    by the Free Software Foundation; either version 3 of the License, or 
+ *    (at your option) any later version.
+ *
+ *    This library is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *    Library General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Library General Public
+ *    License along with this library; if not, write to the
+ *    Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ *    Boston, MA 02111-1307, USA.
+ */
+
+/* 
+ * The algorithm is due to Ron Rivest.  This code is based on code
+ * written by Colin Plumb in 1993.
+ */
+
+
+#include <string.h>
+#include <stdlib.h>
+#include "config.h"
+#include "skey.h"
+#include "skeyutil.h"
+#include "md4.h"
+
+#ifndef WORDS_BIGENDIAN
+#define byteReverse(buf, len)	/* Nothing */
+#else
+static void byteReverse(unsigned char *buf, unsigned longs);
+
+
+/*
+ * Note: this code is harmless on little-endian machines.
+ */
+static void byteReverse(unsigned char *buf, unsigned longs)
+{
+	guint32 t;
+	do {
+		t = (guint32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
+		    ((unsigned) buf[1] << 8 | buf[0]);
+		*(guint32 *) buf = t;
+		buf += 4;
+	} while (--longs);
+}
+#endif
+
+#define rotl32(x,n)   (((x) << ((guint32)(n))) | ((x) >> (32 - (guint32)(n))))
+
+/*
+ * Start MD4 accumulation.  Set bit count to 0 and buffer to mysterious
+ * initialization constants.
+ */
+void MD4Init(MD4_CTX *ctx)
+{
+	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.
+ */
+void MD4Update(MD4_CTX *ctx, unsigned char const *buf,
+	       unsigned len)
+{
+	register guint32 t;
+
+	/* Update bitcount */
+
+	t = ctx->bits[0];
+	if ((ctx->bits[0] = t + ((guint32) 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);
+		MD4Transform(ctx->buf, (guint32 *) ctx->in);
+		buf += t;
+		len -= t;
+	}
+	/* Process data in 64-byte chunks */
+
+	while (len >= 64) {
+		memcpy(ctx->in, buf, 64);
+		byteReverse(ctx->in, 16);
+		MD4Transform(ctx->buf, (guint32 *) 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)
+ */
+void MD4Final(unsigned char* digest, MD4_CTX *ctx)
+{
+	unsigned int 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);
+		MD4Transform(ctx->buf, (guint32 *) 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 */
+	((guint32 *) ctx->in)[14] = ctx->bits[0];
+	((guint32 *) ctx->in)[15] = ctx->bits[1];
+
+	MD4Transform(ctx->buf, (guint32 *) ctx->in);
+	byteReverse((unsigned char *) ctx->buf, 4);
+	
+	if (digest!=NULL)
+		memcpy(digest, ctx->buf, 16);
+	memset(ctx, 0, sizeof(ctx));	/* In case it's sensitive */
+}
+
+/* The three core functions */
+
+#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
+#define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
+#define H(x, y, z) ((x) ^ (y) ^ (z))
+
+#define FF(a, b, c, d, x, s) { \
+    (a) += F ((b), (c), (d)) + (x); \
+    (a) = rotl32 ((a), (s)); \
+  }
+#define GG(a, b, c, d, x, s) { \
+    (a) += G ((b), (c), (d)) + (x) + (guint32)0x5a827999; \
+    (a) = rotl32 ((a), (s)); \
+  }
+#define HH(a, b, c, d, x, s) { \
+    (a) += H ((b), (c), (d)) + (x) + (guint32)0x6ed9eba1; \
+    (a) = rotl32 ((a), (s)); \
+  }
+
+
+/*
+ * The core of the MD4 algorithm
+ */
+void MD4Transform(guint32 buf[4], guint32 const in[16])
+{
+	register guint32 a, b, c, d;
+
+	a = buf[0];
+	b = buf[1];
+	c = buf[2];
+	d = buf[3];
+
+	FF(a, b, c, d, in[0], 3);	/* 1 */
+	FF(d, a, b, c, in[1], 7);	/* 2 */
+	FF(c, d, a, b, in[2], 11);	/* 3 */
+	FF(b, c, d, a, in[3], 19);	/* 4 */
+	FF(a, b, c, d, in[4], 3);	/* 5 */
+	FF(d, a, b, c, in[5], 7);	/* 6 */
+	FF(c, d, a, b, in[6], 11);	/* 7 */
+	FF(b, c, d, a, in[7], 19);	/* 8 */
+	FF(a, b, c, d, in[8], 3);	/* 9 */
+	FF(d, a, b, c, in[9], 7);	/* 10 */
+	FF(c, d, a, b, in[10], 11);	/* 11 */
+	FF(b, c, d, a, in[11], 19);	/* 12 */
+	FF(a, b, c, d, in[12], 3);	/* 13 */
+	FF(d, a, b, c, in[13], 7);	/* 14 */
+	FF(c, d, a, b, in[14], 11);	/* 15 */
+	FF(b, c, d, a, in[15], 19);	/* 16 */
+
+	GG(a, b, c, d, in[0], 3);	/* 17 */
+	GG(d, a, b, c, in[4], 5);	/* 18 */
+	GG(c, d, a, b, in[8], 9);	/* 19 */
+	GG(b, c, d, a, in[12], 13);	/* 20 */
+	GG(a, b, c, d, in[1], 3);	/* 21 */
+	GG(d, a, b, c, in[5], 5);	/* 22 */
+	GG(c, d, a, b, in[9], 9);	/* 23 */
+	GG(b, c, d, a, in[13], 13);	/* 24 */
+	GG(a, b, c, d, in[2], 3);	/* 25 */
+	GG(d, a, b, c, in[6], 5);	/* 26 */
+	GG(c, d, a, b, in[10], 9);	/* 27 */
+	GG(b, c, d, a, in[14], 13);	/* 28 */
+	GG(a, b, c, d, in[3], 3);	/* 29 */
+	GG(d, a, b, c, in[7], 5);	/* 30 */
+	GG(c, d, a, b, in[11], 9);	/* 31 */
+	GG(b, c, d, a, in[15], 13);	/* 32 */
+
+	HH(a, b, c, d, in[0], 3);	/* 33 */
+	HH(d, a, b, c, in[8], 9);	/* 34 */
+	HH(c, d, a, b, in[4], 11);	/* 35 */
+	HH(b, c, d, a, in[12], 15);	/* 36 */
+	HH(a, b, c, d, in[2], 3);	/* 37 */
+	HH(d, a, b, c, in[10], 9);	/* 38 */
+	HH(c, d, a, b, in[6], 11);	/* 39 */
+	HH(b, c, d, a, in[14], 15);	/* 40 */
+	HH(a, b, c, d, in[1], 3);	/* 41 */
+	HH(d, a, b, c, in[9], 9);	/* 42 */
+	HH(c, d, a, b, in[5], 11);	/* 43 */
+	HH(b, c, d, a, in[13], 15);	/* 44 */
+	HH(a, b, c, d, in[3], 3);	/* 45 */
+	HH(d, a, b, c, in[11], 9);	/* 46 */
+	HH(c, d, a, b, in[7], 11);	/* 47 */
+	HH(b, c, d, a, in[15], 15);	/* 48 */
+
+
+	buf[0] += a;
+	buf[1] += b;
+	buf[2] += c;
+	buf[3] += d;
+}
+
+int MD4Keycrunch( char *result, const char *seed, const char *passphrase)
+{
+	int len;
+	char *buf;
+	MD4_CTX md;
+	guint32 results[4];
+
+	len = strlen(seed) + strlen(passphrase);
+	buf = (char *)malloc(len+1);
+	if (buf == NULL)
+		return -1;
+
+	strcpy(buf, seed);
+	skey_lowcase(buf);
+	strcat(buf, passphrase);
+	skey_sevenbit(buf);
+
+	MD4Init(&md);
+	MD4Update(&md, (unsigned char *)buf, len);
+	MD4Final((unsigned char *)results, &md);
+	free(buf);
+
+	results[0] ^= results[2];
+	results[1] ^= results[3];
+	memcpy((void *)result, (void *)results, SKEY_SIZE);
+
+	return 0;
+}
+
+
+void MD4SKey(char *x)
+{
+	MD4_CTX md;
+	guint32 results[4];
+
+	MD4Init(&md);
+	MD4Update(&md, (unsigned char *)x, SKEY_SIZE);
+	MD4Final((unsigned char *)results, &md);
+
+	results[0] ^= results[2];
+	results[1] ^= results[3];
+
+	memcpy((void *)x, (void *)results, SKEY_SIZE);
+}
+
+#ifdef MD4_MAIN
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+int main(int argc, char *argv[])
+{
+	MD4_CTX *md4;
+	unsigned char digest[16];
+	unsigned char data[1024];
+	int i, r;
+
+	memset(digest, 0, 16);
+	printf("MD4 digest algorithm. End with Ctrl-D:\n");
+
+	md4 = (MD4_CTX *)malloc(sizeof(MD4_CTX));
+	MD4Init(md4);
+	do {
+		r = read(0, data, sizeof data);
+		MD4Update(md4, data, r);
+	} while (r);
+
+	MD4Final(digest, md4);
+	printf("MD4 Digest is: ");
+	for (i = 0; i < 16; i++)
+		printf("%02X", digest[i]);
+
+	printf("\n");
+	free(md4);
+	return 0;
+}
+
+#endif