ncpl_crypt.c revision 84213 
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
7#include <sys/cdefs.h>
8__FBSDID("$FreeBSD: head/lib/libncp/ncpl_crypt.c 84213 2001-09-30 22:01:19Z dillon $");
9
10#include <sys/param.h>
11#include <sys/errno.h>
12#include <sys/malloc.h>
13#include <string.h>
14
15/*$*********************************************************
16   $*
17   $* This code has been taken from DDJ 11/93, from an
18   $* article by Pawel Szczerbina.
19   $*
20   $* Password encryption routines follow.
21   $* Converted to C from Barry Nance's Pascal
22   $* prog published in the March -93 issue of Byte.
23   $*
24   $* Adapted to be useable for ncpfs by
25   $* Volker Lendecke <lendecke@namu01.gwdg.de> in
26   $* October 1995.
27   $*
28   $********************************************************* */
29
30
31
32typedef unsigned char buf32[32];
33
34static unsigned char encrypttable[256] = {
350x7, 0x8, 0x0, 0x8, 0x6, 0x4, 0xE, 0x4, 0x5, 0xC, 0x1, 0x7, 0xB, 0xF, 0xA, 0x8,
360xF, 0x8, 0xC, 0xC, 0x9, 0x4, 0x1, 0xE, 0x4, 0x6, 0x2, 0x4, 0x0, 0xA, 0xB, 0x9,
370x2, 0xF, 0xB, 0x1, 0xD, 0x2, 0x1, 0x9, 0x5, 0xE, 0x7, 0x0, 0x0, 0x2, 0x6, 0x6,
380x0, 0x7, 0x3, 0x8, 0x2, 0x9, 0x3, 0xF, 0x7, 0xF, 0xC, 0xF, 0x6, 0x4, 0xA, 0x0,
390x2, 0x3, 0xA, 0xB, 0xD, 0x8, 0x3, 0xA, 0x1, 0x7, 0xC, 0xF, 0x1, 0x8, 0x9, 0xD,
400x9, 0x1, 0x9, 0x4, 0xE, 0x4, 0xC, 0x5, 0x5, 0xC, 0x8, 0xB, 0x2, 0x3, 0x9, 0xE,
410x7, 0x7, 0x6, 0x9, 0xE, 0xF, 0xC, 0x8, 0xD, 0x1, 0xA, 0x6, 0xE, 0xD, 0x0, 0x7,
420x7, 0xA, 0x0, 0x1, 0xF, 0x5, 0x4, 0xB, 0x7, 0xB, 0xE, 0xC, 0x9, 0x5, 0xD, 0x1,
430xB, 0xD, 0x1, 0x3, 0x5, 0xD, 0xE, 0x6, 0x3, 0x0, 0xB, 0xB, 0xF, 0x3, 0x6, 0x4,
440x9, 0xD, 0xA, 0x3, 0x1, 0x4, 0x9, 0x4, 0x8, 0x3, 0xB, 0xE, 0x5, 0x0, 0x5, 0x2,
450xC, 0xB, 0xD, 0x5, 0xD, 0x5, 0xD, 0x2, 0xD, 0x9, 0xA, 0xC, 0xA, 0x0, 0xB, 0x3,
460x5, 0x3, 0x6, 0x9, 0x5, 0x1, 0xE, 0xE, 0x0, 0xE, 0x8, 0x2, 0xD, 0x2, 0x2, 0x0,
470x4, 0xF, 0x8, 0x5, 0x9, 0x6, 0x8, 0x6, 0xB, 0xA, 0xB, 0xF, 0x0, 0x7, 0x2, 0x8,
480xC, 0x7, 0x3, 0xA, 0x1, 0x4, 0x2, 0x5, 0xF, 0x7, 0xA, 0xC, 0xE, 0x5, 0x9, 0x3,
490xE, 0x7, 0x1, 0x2, 0xE, 0x1, 0xF, 0x4, 0xA, 0x6, 0xC, 0x6, 0xF, 0x4, 0x3, 0x0,
500xC, 0x0, 0x3, 0x6, 0xF, 0x8, 0x7, 0xB, 0x2, 0xD, 0xC, 0x6, 0xA, 0xA, 0x8, 0xD
51};
52
53static buf32 encryptkeys = {
54    0x48, 0x93, 0x46, 0x67, 0x98, 0x3D, 0xE6, 0x8D,
55    0xB7, 0x10, 0x7A, 0x26, 0x5A, 0xB9, 0xB1, 0x35,
56    0x6B, 0x0F, 0xD5, 0x70, 0xAE, 0xFB, 0xAD, 0x11,
57    0xF4, 0x47, 0xDC, 0xA7, 0xEC, 0xCF, 0x50, 0xC0
58};
59
60/*
61 * Create table-based 16-bytes hash from a 32-bytes array
62 */
63static void
64nw_hash(buf32 temp, unsigned char *target) {
65	short sum;
66	unsigned char b3;
67	int s, b2, i;
68
69	sum = 0;
70
71	for (b2 = 0; b2 <= 1; ++b2) {
72		for (s = 0; s <= 31; ++s) {
73			b3 = (temp[s] + sum) ^ (temp[(s + sum) & 31] - encryptkeys[s]);
74			sum += b3;
75			temp[s] = b3;
76		}
77	}
78
79	for (i = 0; i <= 15; ++i) {
80		target[i] = encrypttable[temp[2 * i]]
81		    | (encrypttable[temp[2 * i + 1]] << 4);
82	}
83}
84
85
86/*
87 * Create a 16-bytes pattern from given buffer based on a four bytes key
88 */
89void
90nw_keyhash(const u_char *key, const u_char *buf, int buflen, u_char *target) {
91	int b2, d, s;
92	buf32 temp;
93
94	while (buflen > 0 && buf[buflen - 1] == 0)
95		buflen--;
96
97	bzero(temp, sizeof(temp));
98
99	d = 0;
100	while (buflen >= 32) {
101		for (s = 0; s <= 31; ++s)
102			temp[s] ^= buf[d++];
103		buflen -= 32;
104	}
105	b2 = d;
106	if (buflen > 0)	{
107		for (s = 0; s <= 31; ++s) {
108			if (d + buflen == b2) {
109				temp[s] ^= encryptkeys[s];
110				b2 = d;
111			} else
112				temp[s] ^= buf[b2++];
113		}
114	}
115	for (s = 0; s <= 31; ++s)
116		temp[s] ^= key[s & 3];
117
118	nw_hash(temp, target);
119}
120
121/*
122 * Create an 8-bytes pattern from an 8-bytes key and 16-bytes of data
123 */
124void
125nw_encrypt(const u_char *fra, const u_char *buf, u_char *target) {
126	buf32 k;
127	int s;
128
129	nw_keyhash(fra, buf, 16, k);
130	nw_keyhash(fra + 4, buf, 16, k + 16);
131
132	for (s = 0; s < 16; s++)
133		k[s] ^= k[31 - s];
134
135	for (s = 0; s < 8; s++)
136		*target++ = k[s] ^ k[15 - s];
137}
138
139
140