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Initial checkin: beta 0.43
[sgt/putty] / sshdes.c
CommitLineData
374330e2 1#include <assert.h>
2#include "ssh.h"
3
4/*
5
6DES implementation; 1995 Tatu Ylonen <ylo@cs.hut.fi>
7
8This implementation is derived from libdes-3.06, which is copyright
9(c) 1993 Eric Young, and distributed under the GNU GPL or the ARTISTIC licence
10(at the user's option). The original distribution can be found e.g. from
11ftp://ftp.dsi.unimi.it/pub/security/crypt/libdes/libdes-3.06.tar.gz.
12
13This implementation is distributed under the same terms. See
14libdes-README, libdes-ARTISTIC, and libdes-COPYING for more
15information.
16
17*/
18
19/*
20 * $Id: sshdes.c,v 1.1 1999/01/08 13:02:12 simon Exp $
21 * $Log: sshdes.c,v $
22 * Revision 1.1 1999/01/08 13:02:12 simon
23 * Initial checkin: beta 0.43
24 *
25 * Revision 1.1.1.1 1996/02/18 21:38:11 ylo
26 * Imported ssh-1.2.13.
27 *
28 * Revision 1.2 1995/07/13 01:22:57 ylo
29 * Added cvs log.
30 *
31 * $Endlog$
32 */
33
34typedef struct
35{
36 word32 key_schedule[32];
37} DESContext;
38
39/* Sets the des key for the context. Initializes the context. The least
40 significant bit of each byte of the key is ignored as parity. */
41static void des_set_key(unsigned char *key, DESContext *ks);
42
43/* Encrypts 32 bits in l,r, and stores the result in output[0] and output[1].
44 Performs encryption if encrypt is non-zero, and decryption if it is zero.
45 The key context must have been initialized previously with des_set_key. */
46static void des_encrypt(word32 l, word32 r, word32 *output, DESContext *ks,
47 int encrypt);
48
49/* Encrypts len bytes from src to dest in CBC modes. Len must be a multiple
50 of 8. iv will be modified at end to a value suitable for continuing
51 encryption. */
52static void des_cbc_encrypt(DESContext *ks, unsigned char *iv, unsigned char *dest,
53 const unsigned char *src, unsigned int len);
54
55/* Decrypts len bytes from src to dest in CBC modes. Len must be a multiple
56 of 8. iv will be modified at end to a value suitable for continuing
57 decryption. */
58static void des_cbc_decrypt(DESContext *ks, unsigned char *iv, unsigned char *dest,
59 const unsigned char *src, unsigned int len);
60
61/* Encrypts in CBC mode using triple-DES. */
62static void des_3cbc_encrypt(DESContext *ks1, unsigned char *iv1,
63 DESContext *ks2, unsigned char *iv2,
64 DESContext *ks3, unsigned char *iv3,
65 unsigned char *dest, const unsigned char *src,
66 unsigned int len);
67
68/* Decrypts in CBC mode using triple-DES. */
69static void des_3cbc_decrypt(DESContext *ks1, unsigned char *iv1,
70 DESContext *ks2, unsigned char *iv2,
71 DESContext *ks3, unsigned char *iv3,
72 unsigned char *dest, const unsigned char *src,
73 unsigned int len);
74
75#define GET_32BIT_LSB_FIRST(cp) \
76 (((unsigned long)(unsigned char)(cp)[0]) | \
77 ((unsigned long)(unsigned char)(cp)[1] << 8) | \
78 ((unsigned long)(unsigned char)(cp)[2] << 16) | \
79 ((unsigned long)(unsigned char)(cp)[3] << 24))
80
81#define PUT_32BIT_LSB_FIRST(cp, value) do { \
82 (cp)[0] = (value); \
83 (cp)[1] = (value) >> 8; \
84 (cp)[2] = (value) >> 16; \
85 (cp)[3] = (value) >> 24; } while (0)
86
87/*
88
89DES implementation; 1995 Tatu Ylonen <ylo@cs.hut.fi>
90
91This implementation is derived from libdes-3.06, which is copyright
92(c) 1993 Eric Young, and distributed under the GNU GPL or the ARTISTIC licence
93(at the user's option). The original distribution can be found e.g. from
94ftp://ftp.dsi.unimi.it/pub/security/crypt/libdes/libdes-3.06.tar.gz.
95
96This implementation is distributed under the same terms. See
97libdes-README, libdes-ARTISTIC, and libdes-COPYING for more
98information.
99
100A description of the DES algorithm can be found in every modern book on
101cryptography and data security, including the following:
102
103 Bruce Schneier: Applied Cryptography. John Wiley & Sons, 1994.
104
105 Jennifer Seberry and Josed Pieprzyk: Cryptography: An Introduction to
106 Computer Security. Prentice-Hall, 1989.
107
108 Man Young Rhee: Cryptography and Secure Data Communications. McGraw-Hill,
109 1994.
110
111*/
112
113/*
114 * $Id: sshdes.c,v 1.1 1999/01/08 13:02:12 simon Exp $
115 * $Log: sshdes.c,v $
116 * Revision 1.1 1999/01/08 13:02:12 simon
117 * Initial checkin: beta 0.43
118 *
119 * Revision 1.1.1.1 1996/02/18 21:38:11 ylo
120 * Imported ssh-1.2.13.
121 *
122 * Revision 1.2 1995/07/13 01:22:25 ylo
123 * Added cvs log.
124 *
125 * $Endlog$
126 */
127
128/* Table for key generation. This used to be in sk.h. */
129/* Copyright (C) 1993 Eric Young - see README for more details */
130static const word32 des_skb[8][64]={
131/* for C bits (numbered as per FIPS 46) 1 2 3 4 5 6 */
132{ 0x00000000,0x00000010,0x20000000,0x20000010,
1330x00010000,0x00010010,0x20010000,0x20010010,
1340x00000800,0x00000810,0x20000800,0x20000810,
1350x00010800,0x00010810,0x20010800,0x20010810,
1360x00000020,0x00000030,0x20000020,0x20000030,
1370x00010020,0x00010030,0x20010020,0x20010030,
1380x00000820,0x00000830,0x20000820,0x20000830,
1390x00010820,0x00010830,0x20010820,0x20010830,
1400x00080000,0x00080010,0x20080000,0x20080010,
1410x00090000,0x00090010,0x20090000,0x20090010,
1420x00080800,0x00080810,0x20080800,0x20080810,
1430x00090800,0x00090810,0x20090800,0x20090810,
1440x00080020,0x00080030,0x20080020,0x20080030,
1450x00090020,0x00090030,0x20090020,0x20090030,
1460x00080820,0x00080830,0x20080820,0x20080830,
1470x00090820,0x00090830,0x20090820,0x20090830 },
148/* for C bits (numbered as per FIPS 46) 7 8 10 11 12 13 */
149{ 0x00000000,0x02000000,0x00002000,0x02002000,
1500x00200000,0x02200000,0x00202000,0x02202000,
1510x00000004,0x02000004,0x00002004,0x02002004,
1520x00200004,0x02200004,0x00202004,0x02202004,
1530x00000400,0x02000400,0x00002400,0x02002400,
1540x00200400,0x02200400,0x00202400,0x02202400,
1550x00000404,0x02000404,0x00002404,0x02002404,
1560x00200404,0x02200404,0x00202404,0x02202404,
1570x10000000,0x12000000,0x10002000,0x12002000,
1580x10200000,0x12200000,0x10202000,0x12202000,
1590x10000004,0x12000004,0x10002004,0x12002004,
1600x10200004,0x12200004,0x10202004,0x12202004,
1610x10000400,0x12000400,0x10002400,0x12002400,
1620x10200400,0x12200400,0x10202400,0x12202400,
1630x10000404,0x12000404,0x10002404,0x12002404,
1640x10200404,0x12200404,0x10202404,0x12202404 },
165/* for C bits (numbered as per FIPS 46) 14 15 16 17 19 20 */
166{ 0x00000000,0x00000001,0x00040000,0x00040001,
1670x01000000,0x01000001,0x01040000,0x01040001,
1680x00000002,0x00000003,0x00040002,0x00040003,
1690x01000002,0x01000003,0x01040002,0x01040003,
1700x00000200,0x00000201,0x00040200,0x00040201,
1710x01000200,0x01000201,0x01040200,0x01040201,
1720x00000202,0x00000203,0x00040202,0x00040203,
1730x01000202,0x01000203,0x01040202,0x01040203,
1740x08000000,0x08000001,0x08040000,0x08040001,
1750x09000000,0x09000001,0x09040000,0x09040001,
1760x08000002,0x08000003,0x08040002,0x08040003,
1770x09000002,0x09000003,0x09040002,0x09040003,
1780x08000200,0x08000201,0x08040200,0x08040201,
1790x09000200,0x09000201,0x09040200,0x09040201,
1800x08000202,0x08000203,0x08040202,0x08040203,
1810x09000202,0x09000203,0x09040202,0x09040203 },
182/* for C bits (numbered as per FIPS 46) 21 23 24 26 27 28 */
183{ 0x00000000,0x00100000,0x00000100,0x00100100,
1840x00000008,0x00100008,0x00000108,0x00100108,
1850x00001000,0x00101000,0x00001100,0x00101100,
1860x00001008,0x00101008,0x00001108,0x00101108,
1870x04000000,0x04100000,0x04000100,0x04100100,
1880x04000008,0x04100008,0x04000108,0x04100108,
1890x04001000,0x04101000,0x04001100,0x04101100,
1900x04001008,0x04101008,0x04001108,0x04101108,
1910x00020000,0x00120000,0x00020100,0x00120100,
1920x00020008,0x00120008,0x00020108,0x00120108,
1930x00021000,0x00121000,0x00021100,0x00121100,
1940x00021008,0x00121008,0x00021108,0x00121108,
1950x04020000,0x04120000,0x04020100,0x04120100,
1960x04020008,0x04120008,0x04020108,0x04120108,
1970x04021000,0x04121000,0x04021100,0x04121100,
1980x04021008,0x04121008,0x04021108,0x04121108 },
199/* for D bits (numbered as per FIPS 46) 1 2 3 4 5 6 */
200{ 0x00000000,0x10000000,0x00010000,0x10010000,
2010x00000004,0x10000004,0x00010004,0x10010004,
2020x20000000,0x30000000,0x20010000,0x30010000,
2030x20000004,0x30000004,0x20010004,0x30010004,
2040x00100000,0x10100000,0x00110000,0x10110000,
2050x00100004,0x10100004,0x00110004,0x10110004,
2060x20100000,0x30100000,0x20110000,0x30110000,
2070x20100004,0x30100004,0x20110004,0x30110004,
2080x00001000,0x10001000,0x00011000,0x10011000,
2090x00001004,0x10001004,0x00011004,0x10011004,
2100x20001000,0x30001000,0x20011000,0x30011000,
2110x20001004,0x30001004,0x20011004,0x30011004,
2120x00101000,0x10101000,0x00111000,0x10111000,
2130x00101004,0x10101004,0x00111004,0x10111004,
2140x20101000,0x30101000,0x20111000,0x30111000,
2150x20101004,0x30101004,0x20111004,0x30111004 },
216/* for D bits (numbered as per FIPS 46) 8 9 11 12 13 14 */
217{ 0x00000000,0x08000000,0x00000008,0x08000008,
2180x00000400,0x08000400,0x00000408,0x08000408,
2190x00020000,0x08020000,0x00020008,0x08020008,
2200x00020400,0x08020400,0x00020408,0x08020408,
2210x00000001,0x08000001,0x00000009,0x08000009,
2220x00000401,0x08000401,0x00000409,0x08000409,
2230x00020001,0x08020001,0x00020009,0x08020009,
2240x00020401,0x08020401,0x00020409,0x08020409,
2250x02000000,0x0A000000,0x02000008,0x0A000008,
2260x02000400,0x0A000400,0x02000408,0x0A000408,
2270x02020000,0x0A020000,0x02020008,0x0A020008,
2280x02020400,0x0A020400,0x02020408,0x0A020408,
2290x02000001,0x0A000001,0x02000009,0x0A000009,
2300x02000401,0x0A000401,0x02000409,0x0A000409,
2310x02020001,0x0A020001,0x02020009,0x0A020009,
2320x02020401,0x0A020401,0x02020409,0x0A020409 },
233/* for D bits (numbered as per FIPS 46) 16 17 18 19 20 21 */
234{ 0x00000000,0x00000100,0x00080000,0x00080100,
2350x01000000,0x01000100,0x01080000,0x01080100,
2360x00000010,0x00000110,0x00080010,0x00080110,
2370x01000010,0x01000110,0x01080010,0x01080110,
2380x00200000,0x00200100,0x00280000,0x00280100,
2390x01200000,0x01200100,0x01280000,0x01280100,
2400x00200010,0x00200110,0x00280010,0x00280110,
2410x01200010,0x01200110,0x01280010,0x01280110,
2420x00000200,0x00000300,0x00080200,0x00080300,
2430x01000200,0x01000300,0x01080200,0x01080300,
2440x00000210,0x00000310,0x00080210,0x00080310,
2450x01000210,0x01000310,0x01080210,0x01080310,
2460x00200200,0x00200300,0x00280200,0x00280300,
2470x01200200,0x01200300,0x01280200,0x01280300,
2480x00200210,0x00200310,0x00280210,0x00280310,
2490x01200210,0x01200310,0x01280210,0x01280310 },
250/* for D bits (numbered as per FIPS 46) 22 23 24 25 27 28 */
251{ 0x00000000,0x04000000,0x00040000,0x04040000,
2520x00000002,0x04000002,0x00040002,0x04040002,
2530x00002000,0x04002000,0x00042000,0x04042000,
2540x00002002,0x04002002,0x00042002,0x04042002,
2550x00000020,0x04000020,0x00040020,0x04040020,
2560x00000022,0x04000022,0x00040022,0x04040022,
2570x00002020,0x04002020,0x00042020,0x04042020,
2580x00002022,0x04002022,0x00042022,0x04042022,
2590x00000800,0x04000800,0x00040800,0x04040800,
2600x00000802,0x04000802,0x00040802,0x04040802,
2610x00002800,0x04002800,0x00042800,0x04042800,
2620x00002802,0x04002802,0x00042802,0x04042802,
2630x00000820,0x04000820,0x00040820,0x04040820,
2640x00000822,0x04000822,0x00040822,0x04040822,
2650x00002820,0x04002820,0x00042820,0x04042820,
2660x00002822,0x04002822,0x00042822,0x04042822 }
267};
268
269/* Tables used for executing des. This used to be in spr.h. */
270/* Copyright (C) 1993 Eric Young - see README for more details */
271static const word32 des_SPtrans[8][64]={
272/* nibble 0 */
273{ 0x00820200, 0x00020000, 0x80800000, 0x80820200,
2740x00800000, 0x80020200, 0x80020000, 0x80800000,
2750x80020200, 0x00820200, 0x00820000, 0x80000200,
2760x80800200, 0x00800000, 0x00000000, 0x80020000,
2770x00020000, 0x80000000, 0x00800200, 0x00020200,
2780x80820200, 0x00820000, 0x80000200, 0x00800200,
2790x80000000, 0x00000200, 0x00020200, 0x80820000,
2800x00000200, 0x80800200, 0x80820000, 0x00000000,
2810x00000000, 0x80820200, 0x00800200, 0x80020000,
2820x00820200, 0x00020000, 0x80000200, 0x00800200,
2830x80820000, 0x00000200, 0x00020200, 0x80800000,
2840x80020200, 0x80000000, 0x80800000, 0x00820000,
2850x80820200, 0x00020200, 0x00820000, 0x80800200,
2860x00800000, 0x80000200, 0x80020000, 0x00000000,
2870x00020000, 0x00800000, 0x80800200, 0x00820200,
2880x80000000, 0x80820000, 0x00000200, 0x80020200 },
289
290/* nibble 1 */
291{ 0x10042004, 0x00000000, 0x00042000, 0x10040000,
2920x10000004, 0x00002004, 0x10002000, 0x00042000,
2930x00002000, 0x10040004, 0x00000004, 0x10002000,
2940x00040004, 0x10042000, 0x10040000, 0x00000004,
2950x00040000, 0x10002004, 0x10040004, 0x00002000,
2960x00042004, 0x10000000, 0x00000000, 0x00040004,
2970x10002004, 0x00042004, 0x10042000, 0x10000004,
2980x10000000, 0x00040000, 0x00002004, 0x10042004,
2990x00040004, 0x10042000, 0x10002000, 0x00042004,
3000x10042004, 0x00040004, 0x10000004, 0x00000000,
3010x10000000, 0x00002004, 0x00040000, 0x10040004,
3020x00002000, 0x10000000, 0x00042004, 0x10002004,
3030x10042000, 0x00002000, 0x00000000, 0x10000004,
3040x00000004, 0x10042004, 0x00042000, 0x10040000,
3050x10040004, 0x00040000, 0x00002004, 0x10002000,
3060x10002004, 0x00000004, 0x10040000, 0x00042000 },
307
308/* nibble 2 */
309{ 0x41000000, 0x01010040, 0x00000040, 0x41000040,
3100x40010000, 0x01000000, 0x41000040, 0x00010040,
3110x01000040, 0x00010000, 0x01010000, 0x40000000,
3120x41010040, 0x40000040, 0x40000000, 0x41010000,
3130x00000000, 0x40010000, 0x01010040, 0x00000040,
3140x40000040, 0x41010040, 0x00010000, 0x41000000,
3150x41010000, 0x01000040, 0x40010040, 0x01010000,
3160x00010040, 0x00000000, 0x01000000, 0x40010040,
3170x01010040, 0x00000040, 0x40000000, 0x00010000,
3180x40000040, 0x40010000, 0x01010000, 0x41000040,
3190x00000000, 0x01010040, 0x00010040, 0x41010000,
3200x40010000, 0x01000000, 0x41010040, 0x40000000,
3210x40010040, 0x41000000, 0x01000000, 0x41010040,
3220x00010000, 0x01000040, 0x41000040, 0x00010040,
3230x01000040, 0x00000000, 0x41010000, 0x40000040,
3240x41000000, 0x40010040, 0x00000040, 0x01010000 },
325
326/* nibble 3 */
327{ 0x00100402, 0x04000400, 0x00000002, 0x04100402,
3280x00000000, 0x04100000, 0x04000402, 0x00100002,
3290x04100400, 0x04000002, 0x04000000, 0x00000402,
3300x04000002, 0x00100402, 0x00100000, 0x04000000,
3310x04100002, 0x00100400, 0x00000400, 0x00000002,
3320x00100400, 0x04000402, 0x04100000, 0x00000400,
3330x00000402, 0x00000000, 0x00100002, 0x04100400,
3340x04000400, 0x04100002, 0x04100402, 0x00100000,
3350x04100002, 0x00000402, 0x00100000, 0x04000002,
3360x00100400, 0x04000400, 0x00000002, 0x04100000,
3370x04000402, 0x00000000, 0x00000400, 0x00100002,
3380x00000000, 0x04100002, 0x04100400, 0x00000400,
3390x04000000, 0x04100402, 0x00100402, 0x00100000,
3400x04100402, 0x00000002, 0x04000400, 0x00100402,
3410x00100002, 0x00100400, 0x04100000, 0x04000402,
3420x00000402, 0x04000000, 0x04000002, 0x04100400 },
343
344/* nibble 4 */
345{ 0x02000000, 0x00004000, 0x00000100, 0x02004108,
3460x02004008, 0x02000100, 0x00004108, 0x02004000,
3470x00004000, 0x00000008, 0x02000008, 0x00004100,
3480x02000108, 0x02004008, 0x02004100, 0x00000000,
3490x00004100, 0x02000000, 0x00004008, 0x00000108,
3500x02000100, 0x00004108, 0x00000000, 0x02000008,
3510x00000008, 0x02000108, 0x02004108, 0x00004008,
3520x02004000, 0x00000100, 0x00000108, 0x02004100,
3530x02004100, 0x02000108, 0x00004008, 0x02004000,
3540x00004000, 0x00000008, 0x02000008, 0x02000100,
3550x02000000, 0x00004100, 0x02004108, 0x00000000,
3560x00004108, 0x02000000, 0x00000100, 0x00004008,
3570x02000108, 0x00000100, 0x00000000, 0x02004108,
3580x02004008, 0x02004100, 0x00000108, 0x00004000,
3590x00004100, 0x02004008, 0x02000100, 0x00000108,
3600x00000008, 0x00004108, 0x02004000, 0x02000008 },
361
362/* nibble 5 */
363{ 0x20000010, 0x00080010, 0x00000000, 0x20080800,
3640x00080010, 0x00000800, 0x20000810, 0x00080000,
3650x00000810, 0x20080810, 0x00080800, 0x20000000,
3660x20000800, 0x20000010, 0x20080000, 0x00080810,
3670x00080000, 0x20000810, 0x20080010, 0x00000000,
3680x00000800, 0x00000010, 0x20080800, 0x20080010,
3690x20080810, 0x20080000, 0x20000000, 0x00000810,
3700x00000010, 0x00080800, 0x00080810, 0x20000800,
3710x00000810, 0x20000000, 0x20000800, 0x00080810,
3720x20080800, 0x00080010, 0x00000000, 0x20000800,
3730x20000000, 0x00000800, 0x20080010, 0x00080000,
3740x00080010, 0x20080810, 0x00080800, 0x00000010,
3750x20080810, 0x00080800, 0x00080000, 0x20000810,
3760x20000010, 0x20080000, 0x00080810, 0x00000000,
3770x00000800, 0x20000010, 0x20000810, 0x20080800,
3780x20080000, 0x00000810, 0x00000010, 0x20080010 },
379
380/* nibble 6 */
381{ 0x00001000, 0x00000080, 0x00400080, 0x00400001,
3820x00401081, 0x00001001, 0x00001080, 0x00000000,
3830x00400000, 0x00400081, 0x00000081, 0x00401000,
3840x00000001, 0x00401080, 0x00401000, 0x00000081,
3850x00400081, 0x00001000, 0x00001001, 0x00401081,
3860x00000000, 0x00400080, 0x00400001, 0x00001080,
3870x00401001, 0x00001081, 0x00401080, 0x00000001,
3880x00001081, 0x00401001, 0x00000080, 0x00400000,
3890x00001081, 0x00401000, 0x00401001, 0x00000081,
3900x00001000, 0x00000080, 0x00400000, 0x00401001,
3910x00400081, 0x00001081, 0x00001080, 0x00000000,
3920x00000080, 0x00400001, 0x00000001, 0x00400080,
3930x00000000, 0x00400081, 0x00400080, 0x00001080,
3940x00000081, 0x00001000, 0x00401081, 0x00400000,
3950x00401080, 0x00000001, 0x00001001, 0x00401081,
3960x00400001, 0x00401080, 0x00401000, 0x00001001 },
397
398/* nibble 7 */
399{ 0x08200020, 0x08208000, 0x00008020, 0x00000000,
4000x08008000, 0x00200020, 0x08200000, 0x08208020,
4010x00000020, 0x08000000, 0x00208000, 0x00008020,
4020x00208020, 0x08008020, 0x08000020, 0x08200000,
4030x00008000, 0x00208020, 0x00200020, 0x08008000,
4040x08208020, 0x08000020, 0x00000000, 0x00208000,
4050x08000000, 0x00200000, 0x08008020, 0x08200020,
4060x00200000, 0x00008000, 0x08208000, 0x00000020,
4070x00200000, 0x00008000, 0x08000020, 0x08208020,
4080x00008020, 0x08000000, 0x00000000, 0x00208000,
4090x08200020, 0x08008020, 0x08008000, 0x00200020,
4100x08208000, 0x00000020, 0x00200020, 0x08008000,
4110x08208020, 0x00200000, 0x08200000, 0x08000020,
4120x00208000, 0x00008020, 0x08008020, 0x08200000,
4130x00000020, 0x08208000, 0x00208020, 0x00000000,
4140x08000000, 0x08200020, 0x00008000, 0x00208020 }};
415
416/* Some stuff that used to be in des_locl.h. Heavily modified. */
417 /* IP and FP
418 * The problem is more of a geometric problem that random bit fiddling.
419 0 1 2 3 4 5 6 7 62 54 46 38 30 22 14 6
420 8 9 10 11 12 13 14 15 60 52 44 36 28 20 12 4
421 16 17 18 19 20 21 22 23 58 50 42 34 26 18 10 2
422 24 25 26 27 28 29 30 31 to 56 48 40 32 24 16 8 0
423
424 32 33 34 35 36 37 38 39 63 55 47 39 31 23 15 7
425 40 41 42 43 44 45 46 47 61 53 45 37 29 21 13 5
426 48 49 50 51 52 53 54 55 59 51 43 35 27 19 11 3
427 56 57 58 59 60 61 62 63 57 49 41 33 25 17 9 1
428
429 The output has been subject to swaps of the form
430 0 1 -> 3 1 but the odd and even bits have been put into
431 2 3 2 0
432 different words. The main trick is to remember that
433 t=((l>>size)^r)&(mask);
434 r^=t;
435 l^=(t<<size);
436 can be used to swap and move bits between words.
437
438 So l = 0 1 2 3 r = 16 17 18 19
439 4 5 6 7 20 21 22 23
440 8 9 10 11 24 25 26 27
441 12 13 14 15 28 29 30 31
442 becomes (for size == 2 and mask == 0x3333)
443 t = 2^16 3^17 -- -- l = 0 1 16 17 r = 2 3 18 19
444 6^20 7^21 -- -- 4 5 20 21 6 7 22 23
445 10^24 11^25 -- -- 8 9 24 25 10 11 24 25
446 14^28 15^29 -- -- 12 13 28 29 14 15 28 29
447
448 Thanks for hints from Richard Outerbridge - he told me IP&FP
449 could be done in 15 xor, 10 shifts and 5 ands.
450 When I finally started to think of the problem in 2D
451 I first got ~42 operations without xors. When I remembered
452 how to use xors :-) I got it to its final state.
453 */
454#define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
455 (b)^=(t),\
456 (a)^=((t)<<(n)))
457
458#define IP(l,r,t) \
459 PERM_OP(r,l,t, 4,0x0f0f0f0f); \
460 PERM_OP(l,r,t,16,0x0000ffff); \
461 PERM_OP(r,l,t, 2,0x33333333); \
462 PERM_OP(l,r,t, 8,0x00ff00ff); \
463 PERM_OP(r,l,t, 1,0x55555555);
464
465#define FP(l,r,t) \
466 PERM_OP(l,r,t, 1,0x55555555); \
467 PERM_OP(r,l,t, 8,0x00ff00ff); \
468 PERM_OP(l,r,t, 2,0x33333333); \
469 PERM_OP(r,l,t,16,0x0000ffff); \
470 PERM_OP(l,r,t, 4,0x0f0f0f0f);
471
472#define D_ENCRYPT(L,R,S) \
473 u=(R^s[S ]); \
474 t=R^s[S+1]; \
475 t=((t>>4)+(t<<28)); \
476 L^= des_SPtrans[1][(t )&0x3f]| \
477 des_SPtrans[3][(t>> 8)&0x3f]| \
478 des_SPtrans[5][(t>>16)&0x3f]| \
479 des_SPtrans[7][(t>>24)&0x3f]| \
480 des_SPtrans[0][(u )&0x3f]| \
481 des_SPtrans[2][(u>> 8)&0x3f]| \
482 des_SPtrans[4][(u>>16)&0x3f]| \
483 des_SPtrans[6][(u>>24)&0x3f];
484
485/* This part is based on code that used to be in ecb_enc.c. */
486/* Copyright (C) 1993 Eric Young - see README for more details */
487
488static void des_encrypt(word32 l, word32 r, word32 *output, DESContext *ks,
489 int encrypt)
490{
491 register word32 t,u;
492 register int i;
493 register word32 *s;
494
495 s = ks->key_schedule;
496
497 IP(l,r,t);
498 /* Things have been modified so that the initial rotate is
499 * done outside the loop. This required the
500 * des_SPtrans values in sp.h to be rotated 1 bit to the right.
501 * One perl script later and things have a 5% speed up on a sparc2.
502 * Thanks to Richard Outerbridge <71755.204@CompuServe.COM>
503 * for pointing this out. */
504 t=(r<<1)|(r>>31);
505 r=(l<<1)|(l>>31);
506 l=t;
507
508 /* I don't know if it is worth the effort of loop unrolling the
509 * inner loop */
510 if (encrypt)
511 {
512 for (i=0; i<32; i+=4)
513 {
514 D_ENCRYPT(l,r,i+0); /* 1 */
515 D_ENCRYPT(r,l,i+2); /* 2 */
516 }
517 }
518 else
519 {
520 for (i=30; i>0; i-=4)
521 {
522 D_ENCRYPT(l,r,i-0); /* 16 */
523 D_ENCRYPT(r,l,i-2); /* 15 */
524 }
525 }
526 l=(l>>1)|(l<<31);
527 r=(r>>1)|(r<<31);
528
529 FP(r,l,t);
530 output[0]=l;
531 output[1]=r;
532}
533
534/* Code based on set_key.c. */
535/* Copyright (C) 1993 Eric Young - see README for more details */
536
537#define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
538 (a)=(a)^(t)^(t>>(16-(n))))
539
540static void des_set_key(unsigned char *key, DESContext *ks)
541{
542 register word32 c, d, t, s, shifts;
543 register int i;
544 register word32 *schedule;
545
546 schedule = ks->key_schedule;
547
548 c = GET_32BIT_LSB_FIRST(key);
549 d = GET_32BIT_LSB_FIRST(key + 4);
550
551 /* I now do it in 47 simple operations :-)
552 * Thanks to John Fletcher (john_fletcher@lccmail.ocf.llnl.gov)
553 * for the inspiration. :-) */
554 PERM_OP(d,c,t,4,0x0f0f0f0f);
555 HPERM_OP(c,t,-2,0xcccc0000);
556 HPERM_OP(d,t,-2,0xcccc0000);
557 PERM_OP(d,c,t,1,0x55555555);
558 PERM_OP(c,d,t,8,0x00ff00ff);
559 PERM_OP(d,c,t,1,0x55555555);
560 d = ((d & 0xff) << 16) | (d & 0xff00) |
561 ((d >> 16) & 0xff) | ((c >> 4) & 0xf000000);
562 c&=0x0fffffff;
563
564 shifts = 0x7efc;
565 for (i=0; i < 16; i++)
566 {
567 if (shifts & 1)
568 { c=((c>>2)|(c<<26)); d=((d>>2)|(d<<26)); }
569 else
570 { c=((c>>1)|(c<<27)); d=((d>>1)|(d<<27)); }
571 shifts >>= 1;
572 c&=0x0fffffff;
573 d&=0x0fffffff;
574
575 /* could be a few less shifts but I am to lazy at this
576 * point in time to investigate */
577
578 s = des_skb[0][ (c )&0x3f ] |
579 des_skb[1][((c>> 6)&0x03)|((c>> 7)&0x3c)] |
580 des_skb[2][((c>>13)&0x0f)|((c>>14)&0x30)] |
581 des_skb[3][((c>>20)&0x01)|((c>>21)&0x06)|((c>>22)&0x38)];
582
583 t = des_skb[4][ (d )&0x3f ] |
584 des_skb[5][((d>> 7)&0x03)|((d>> 8)&0x3c)] |
585 des_skb[6][ (d>>15)&0x3f ] |
586 des_skb[7][((d>>21)&0x0f)|((d>>22)&0x30)];
587
588 /* table contained 0213 4657 */
589 *schedule++ = ((t << 16) | (s & 0xffff));
590 s = ((s >> 16) | (t & 0xffff0000));
591 *schedule++ = (s << 4) | (s >> 28);
592 }
593}
594
595static void des_cbc_encrypt(DESContext *ks, unsigned char *iv,
596 unsigned char *dest, const unsigned char *src,
597 unsigned int len)
598{
599 word32 iv0, iv1, out[2];
600 unsigned int i;
601
602 assert((len & 7) == 0);
603
604 iv0 = GET_32BIT_LSB_FIRST(iv);
605 iv1 = GET_32BIT_LSB_FIRST(iv + 4);
606
607 for (i = 0; i < len; i += 8)
608 {
609 iv0 ^= GET_32BIT_LSB_FIRST(src + i);
610 iv1 ^= GET_32BIT_LSB_FIRST(src + i + 4);
611 des_encrypt(iv0, iv1, out, ks, 1);
612 iv0 = out[0];
613 iv1 = out[1];
614 PUT_32BIT_LSB_FIRST(dest + i, iv0);
615 PUT_32BIT_LSB_FIRST(dest + i + 4, iv1);
616 }
617 PUT_32BIT_LSB_FIRST(iv, iv0);
618 PUT_32BIT_LSB_FIRST(iv + 4, iv1);
619}
620
621static void des_cbc_decrypt(DESContext *ks, unsigned char *iv,
622 unsigned char *dest, const unsigned char *src,
623 unsigned int len)
624{
625 word32 iv0, iv1, d0, d1, out[2];
626 unsigned int i;
627
628 assert((len & 7) == 0);
629
630 iv0 = GET_32BIT_LSB_FIRST(iv);
631 iv1 = GET_32BIT_LSB_FIRST(iv + 4);
632
633 for (i = 0; i < len; i += 8)
634 {
635 d0 = GET_32BIT_LSB_FIRST(src + i);
636 d1 = GET_32BIT_LSB_FIRST(src + i + 4);
637 des_encrypt(d0, d1, out, ks, 0);
638 iv0 ^= out[0];
639 iv1 ^= out[1];
640 PUT_32BIT_LSB_FIRST(dest + i, iv0);
641 PUT_32BIT_LSB_FIRST(dest + i + 4, iv1);
642 iv0 = d0;
643 iv1 = d1;
644 }
645 PUT_32BIT_LSB_FIRST(iv, iv0);
646 PUT_32BIT_LSB_FIRST(iv + 4, iv1);
647}
648
649static void des_3cbc_encrypt(DESContext *ks1, unsigned char *iv1,
650 DESContext *ks2, unsigned char *iv2,
651 DESContext *ks3, unsigned char *iv3,
652 unsigned char *dest, const unsigned char *src,
653 unsigned int len)
654{
655 des_cbc_encrypt(ks1, iv1, dest, src, len);
656 des_cbc_decrypt(ks2, iv2, dest, dest, len);
657 des_cbc_encrypt(ks3, iv3, dest, dest, len);
658}
659
660static void des_3cbc_decrypt(DESContext *ks1, unsigned char *iv1,
661 DESContext *ks2, unsigned char *iv2,
662 DESContext *ks3, unsigned char *iv3,
663 unsigned char *dest, const unsigned char *src,
664 unsigned int len)
665{
666 des_cbc_decrypt(ks3, iv3, dest, src, len);
667 des_cbc_encrypt(ks2, iv2, dest, dest, len);
668 des_cbc_decrypt(ks1, iv1, dest, dest, len);
669}
670
671DESContext ekey1, ekey2, ekey3;
672unsigned char eiv1[8], eiv2[8], eiv3[8];
673
674DESContext dkey1, dkey2, dkey3;
675unsigned char div1[8], div2[8], div3[8];
676
677static void des3_sesskey(unsigned char *key) {
678 des_set_key(key, &ekey1);
679 des_set_key(key+8, &ekey2);
680 des_set_key(key+16, &ekey3);
681 memset(eiv1, 0, sizeof(eiv1));
682 memset(eiv2, 0, sizeof(eiv2));
683 memset(eiv3, 0, sizeof(eiv3));
684 des_set_key(key, &dkey1);
685 des_set_key(key+8, &dkey2);
686 des_set_key(key+16, &dkey3);
687 memset(div1, 0, sizeof(div1));
688 memset(div2, 0, sizeof(div2));
689 memset(div3, 0, sizeof(div3));
690}
691
692static void des3_encrypt_blk(unsigned char *blk, int len) {
693 des_3cbc_encrypt(&ekey1, eiv1, &ekey2, eiv2, &ekey3, eiv3, blk, blk, len);
694}
695
696static void des3_decrypt_blk(unsigned char *blk, int len) {
697 des_3cbc_decrypt(&dkey1, div1, &dkey2, div2, &dkey3, div3, blk, blk, len);
698}
699
700struct ssh_cipher ssh_3des = {
701 des3_sesskey,
702 des3_encrypt_blk,
703 des3_decrypt_blk
704};
705
706#ifdef DES_TEST
707
708void des_encrypt_buf(DESContext *ks, unsigned char *out,
709 const unsigned char *in, int encrypt)
710{
711 word32 in0, in1, output[0];
712
713 in0 = GET_32BIT_LSB_FIRST(in);
714 in1 = GET_32BIT_LSB_FIRST(in + 4);
715 des_encrypt(in0, in1, output, ks, encrypt);
716 PUT_32BIT_LSB_FIRST(out, output[0]);
717 PUT_32BIT_LSB_FIRST(out + 4, output[1]);
718}
719
720int main(int ac, char **av)
721{
722 FILE *f;
723 char line[1024], *cp;
724 int i, value;
725 unsigned char key[8], data[8], result[8], output[8];
726 DESContext ks;
727
728 while (fgets(line, sizeof(line), stdin))
729 {
730 for (i = 0; i < 8; i++)
731 {
732 if (sscanf(line + 2 * i, "%02x", &value) != 1)
733 {
734 fprintf(stderr, "1st col, i = %d, line: %s", i, line);
735 exit(1);
736 }
737 key[i] = value;
738 }
739 for (i = 0; i < 8; i++)
740 {
741 if (sscanf(line + 2 * i + 17, "%02x", &value) != 1)
742 {
743 fprintf(stderr, "2nd col, i = %d, line: %s", i, line);
744 exit(1);
745 }
746 data[i] = value;
747 }
748 for (i = 0; i < 8; i++)
749 {
750 if (sscanf(line + 2 * i + 2*17, "%02x", &value) != 1)
751 {
752 fprintf(stderr, "3rd col, i = %d, line: %s", i, line);
753 exit(1);
754 }
755 result[i] = value;
756 }
757 des_set_key(key, &ks);
758 des_encrypt_buf(&ks, output, data, 1);
759 if (memcmp(output, result, 8) != 0)
760 fprintf(stderr, "Encrypt failed: %s", line);
761 des_encrypt_buf(&ks, output, result, 0);
762 if (memcmp(output, data, 8) != 0)
763 fprintf(stderr, "Decrypt failed: %s", line);
764 }
765 exit(0);
766}
767#endif /* DES_TEST */
768
Simon Tatham's PuTTY GUI SSH client; import of svn://svn.tartarus.org/sgt/putty