ncpl_crypt.c revision 52153 
1/*
2 *  Routines in this file based on the work of Volker Lendecke,
3 *  Adapted for ncplib by Boris Popov
4 *  Please note that ncpl_crypt.c file should be indentical to this one
5 *
6 * $FreeBSD: head/lib/libncp/ncpl_crypt.c 52153 1999-10-12 11:56:41Z bp $
7 */
8#include <sys/param.h>
9#include <sys/errno.h>
10#include <sys/malloc.h>
11#include <string.h>
12
13/*$*********************************************************
14   $*
15   $* This code has been taken from DDJ 11/93, from an
16   $* article by Pawel Szczerbina.
17   $*
18   $* Password encryption routines follow.
19   $* Converted to C from Barry Nance's Pascal
20   $* prog published in the March -93 issue of Byte.
21   $*
22   $* Adapted to be useable for ncpfs by
23   $* Volker Lendecke <lendecke@namu01.gwdg.de> in
24   $* October 1995.
25   $*
26   $********************************************************* */
27
28
29
30typedef unsigned char buf32[32];
31
32static unsigned char encrypttable[256] = {
330x7, 0x8, 0x0, 0x8, 0x6, 0x4, 0xE, 0x4, 0x5, 0xC, 0x1, 0x7, 0xB, 0xF, 0xA, 0x8,
340xF, 0x8, 0xC, 0xC, 0x9, 0x4, 0x1, 0xE, 0x4, 0x6, 0x2, 0x4, 0x0, 0xA, 0xB, 0x9,
350x2, 0xF, 0xB, 0x1, 0xD, 0x2, 0x1, 0x9, 0x5, 0xE, 0x7, 0x0, 0x0, 0x2, 0x6, 0x6,
360x0, 0x7, 0x3, 0x8, 0x2, 0x9, 0x3, 0xF, 0x7, 0xF, 0xC, 0xF, 0x6, 0x4, 0xA, 0x0,
370x2, 0x3, 0xA, 0xB, 0xD, 0x8, 0x3, 0xA, 0x1, 0x7, 0xC, 0xF, 0x1, 0x8, 0x9, 0xD,
380x9, 0x1, 0x9, 0x4, 0xE, 0x4, 0xC, 0x5, 0x5, 0xC, 0x8, 0xB, 0x2, 0x3, 0x9, 0xE,
390x7, 0x7, 0x6, 0x9, 0xE, 0xF, 0xC, 0x8, 0xD, 0x1, 0xA, 0x6, 0xE, 0xD, 0x0, 0x7,
400x7, 0xA, 0x0, 0x1, 0xF, 0x5, 0x4, 0xB, 0x7, 0xB, 0xE, 0xC, 0x9, 0x5, 0xD, 0x1,
410xB, 0xD, 0x1, 0x3, 0x5, 0xD, 0xE, 0x6, 0x3, 0x0, 0xB, 0xB, 0xF, 0x3, 0x6, 0x4,
420x9, 0xD, 0xA, 0x3, 0x1, 0x4, 0x9, 0x4, 0x8, 0x3, 0xB, 0xE, 0x5, 0x0, 0x5, 0x2,
430xC, 0xB, 0xD, 0x5, 0xD, 0x5, 0xD, 0x2, 0xD, 0x9, 0xA, 0xC, 0xA, 0x0, 0xB, 0x3,
440x5, 0x3, 0x6, 0x9, 0x5, 0x1, 0xE, 0xE, 0x0, 0xE, 0x8, 0x2, 0xD, 0x2, 0x2, 0x0,
450x4, 0xF, 0x8, 0x5, 0x9, 0x6, 0x8, 0x6, 0xB, 0xA, 0xB, 0xF, 0x0, 0x7, 0x2, 0x8,
460xC, 0x7, 0x3, 0xA, 0x1, 0x4, 0x2, 0x5, 0xF, 0x7, 0xA, 0xC, 0xE, 0x5, 0x9, 0x3,
470xE, 0x7, 0x1, 0x2, 0xE, 0x1, 0xF, 0x4, 0xA, 0x6, 0xC, 0x6, 0xF, 0x4, 0x3, 0x0,
480xC, 0x0, 0x3, 0x6, 0xF, 0x8, 0x7, 0xB, 0x2, 0xD, 0xC, 0x6, 0xA, 0xA, 0x8, 0xD
49};
50
51static buf32 encryptkeys = {
52    0x48, 0x93, 0x46, 0x67, 0x98, 0x3D, 0xE6, 0x8D,
53    0xB7, 0x10, 0x7A, 0x26, 0x5A, 0xB9, 0xB1, 0x35,
54    0x6B, 0x0F, 0xD5, 0x70, 0xAE, 0xFB, 0xAD, 0x11,
55    0xF4, 0x47, 0xDC, 0xA7, 0xEC, 0xCF, 0x50, 0xC0
56};
57
58/*
59 * Create table-based 16-bytes hash from a 32-bytes array
60 */
61static void
62nw_hash(buf32 temp, unsigned char *target) {
63	short sum;
64	unsigned char b3;
65	int s, b2, i;
66
67	sum = 0;
68
69	for (b2 = 0; b2 <= 1; ++b2) {
70		for (s = 0; s <= 31; ++s) {
71			b3 = (temp[s] + sum) ^ (temp[(s + sum) & 31] - encryptkeys[s]);
72			sum += b3;
73			temp[s] = b3;
74		}
75	}
76
77	for (i = 0; i <= 15; ++i) {
78		target[i] = encrypttable[temp[2 * i]]
79		    | (encrypttable[temp[2 * i + 1]] << 4);
80	}
81}
82
83
84/*
85 * Create a 16-bytes pattern from given buffer based on a four bytes key
86 */
87void
88nw_keyhash(const u_char *key, const u_char *buf, int buflen, u_char *target) {
89	int b2, d, s;
90	buf32 temp;
91
92	while (buflen > 0 && buf[buflen - 1] == 0)
93		buflen--;
94
95	bzero(temp, sizeof(temp));
96
97	d = 0;
98	while (buflen >= 32) {
99		for (s = 0; s <= 31; ++s)
100			temp[s] ^= buf[d++];
101		buflen -= 32;
102	}
103	b2 = d;
104	if (buflen > 0)	{
105		for (s = 0; s <= 31; ++s) {
106			if (d + buflen == b2) {
107				temp[s] ^= encryptkeys[s];
108				b2 = d;
109			} else
110				temp[s] ^= buf[b2++];
111		}
112	}
113	for (s = 0; s <= 31; ++s)
114		temp[s] ^= key[s & 3];
115
116	nw_hash(temp, target);
117}
118
119/*
120 * Create an 8-bytes pattern from an 8-bytes key and 16-bytes of data
121 */
122void
123nw_encrypt(const u_char *fra, const u_char *buf, u_char *target) {
124	buf32 k;
125	int s;
126
127	nw_keyhash(fra, buf, 16, k);
128	nw_keyhash(fra + 4, buf, 16, k + 16);
129
130	for (s = 0; s < 16; s++)
131		k[s] ^= k[31 - s];
132
133	for (s = 0; s < 8; s++)
134		*target++ = k[s] ^ k[15 - s];
135}
136
137
138