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1.1 root 1: /* crypto/des/set_key.c */
2: /* Copyright (C) 1995-1997 Eric Young ([email protected])
3: * All rights reserved.
4: *
5: * This package is an SSL implementation written
6: * by Eric Young ([email protected]).
7: * The implementation was written so as to conform with Netscapes SSL.
8: *
9: * This library is free for commercial and non-commercial use as long as
10: * the following conditions are aheared to. The following conditions
11: * apply to all code found in this distribution, be it the RC4, RSA,
12: * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13: * included with this distribution is covered by the same copyright terms
14: * except that the holder is Tim Hudson ([email protected]).
15: *
16: * Copyright remains Eric Young's, and as such any Copyright notices in
17: * the code are not to be removed.
18: * If this package is used in a product, Eric Young should be given attribution
19: * as the author of the parts of the library used.
20: * This can be in the form of a textual message at program startup or
21: * in documentation (online or textual) provided with the package.
22: *
23: * Redistribution and use in source and binary forms, with or without
24: * modification, are permitted provided that the following conditions
25: * are met:
26: * 1. Redistributions of source code must retain the copyright
27: * notice, this list of conditions and the following disclaimer.
28: * 2. Redistributions in binary form must reproduce the above copyright
29: * notice, this list of conditions and the following disclaimer in the
30: * documentation and/or other materials provided with the distribution.
31: * 3. All advertising materials mentioning features or use of this software
32: * must display the following acknowledgement:
33: * "This product includes cryptographic software written by
34: * Eric Young ([email protected])"
35: * The word 'cryptographic' can be left out if the rouines from the library
36: * being used are not cryptographic related :-).
37: * 4. If you include any Windows specific code (or a derivative thereof) from
38: * the apps directory (application code) you must include an acknowledgement:
39: * "This product includes software written by Tim Hudson ([email protected])"
40: *
41: * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44: * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51: * SUCH DAMAGE.
52: *
53: * The licence and distribution terms for any publically available version or
54: * derivative of this code cannot be changed. i.e. this code cannot simply be
55: * copied and put under another distribution licence
56: * [including the GNU Public Licence.]
57: */
58:
59: /* set_key.c v 1.4 eay 24/9/91
60: * 1.4 Speed up by 400% :-)
61: * 1.3 added register declarations.
62: * 1.2 unrolled make_key_sched a bit more
63: * 1.1 added norm_expand_bits
64: * 1.0 First working version
65: */
66:
67: #include "des_locl.h"
68: #include "podd.h"
69: #include "sk.h"
70:
71: #pragma intrinsic(memcmp,_lrotr)
72:
73:
74: #ifndef NOPROTO
75: static int check_parity(des_cblock (*key));
76: #else
77: static int check_parity();
78: #endif
79:
80: #pragma warning( disable : 4131 )
81:
82: int des_check_key=0;
83:
84: void des_set_odd_parity(key)
85: des_cblock (*key);
86: {
87: int i;
88:
89: for (i=0; i<DES_KEY_SZ; i++)
90: (*key)[i]=odd_parity[(*key)[i]];
91: }
92:
93: static int check_parity(key)
94: des_cblock (*key);
95: {
96: int i;
97:
98: for (i=0; i<DES_KEY_SZ; i++)
99: {
100: if ((*key)[i] != odd_parity[(*key)[i]])
101: return(0);
102: }
103: return(1);
104: }
105:
106: /* Weak and semi week keys as take from
107: * %A D.W. Davies
108: * %A W.L. Price
109: * %T Security for Computer Networks
110: * %I John Wiley & Sons
111: * %D 1984
112: * Many thanks to [email protected] (Steven Bellovin) for the reference
113: * (and actual cblock values).
114: */
115: #define NUM_WEAK_KEY 16
116: static des_cblock weak_keys[NUM_WEAK_KEY]={
117: /* weak keys */
118: {0x01,0x01,0x01,0x01,0x01,0x01,0x01,0x01},
119: {0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE},
120: {0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F,0x1F},
121: {0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0,0xE0},
122: /* semi-weak keys */
123: {0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE},
124: {0xFE,0x01,0xFE,0x01,0xFE,0x01,0xFE,0x01},
125: {0x1F,0xE0,0x1F,0xE0,0x0E,0xF1,0x0E,0xF1},
126: {0xE0,0x1F,0xE0,0x1F,0xF1,0x0E,0xF1,0x0E},
127: {0x01,0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1},
128: {0xE0,0x01,0xE0,0x01,0xF1,0x01,0xF1,0x01},
129: {0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E,0xFE},
130: {0xFE,0x1F,0xFE,0x1F,0xFE,0x0E,0xFE,0x0E},
131: {0x01,0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E},
132: {0x1F,0x01,0x1F,0x01,0x0E,0x01,0x0E,0x01},
133: {0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1,0xFE},
134: {0xFE,0xE0,0xFE,0xE0,0xFE,0xF1,0xFE,0xF1}};
135:
136: int des_is_weak_key(key)
137: des_cblock (*key);
138: {
139: int i;
140:
141: for (i=0; i<NUM_WEAK_KEY; i++)
142: /* Added == 0 to comparision, I obviously don't run
143: * this section very often :-(, thanks to
144: * [email protected] for the fix
145: * eay 93/06/29
146: * Another problem, I was comparing only the first 4
147: * bytes, 97/03/18 */
148: if (memcmp(weak_keys[i],key,sizeof(des_cblock)) == 0) return(1);
149: return(0);
150: }
151:
152: /* NOW DEFINED IN des_local.h
153: * See ecb_encrypt.c for a pseudo description of these macros.
154: * #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
155: * (b)^=(t),\
156: * (a)=((a)^((t)<<(n))))
157: */
158:
159: #define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
160: (a)=(a)^(t)^(t>>(16-(n))))
161:
162: /* return 0 if key parity is odd (correct),
163: * return -1 if key parity error,
164: * return -2 if illegal weak key.
165: */
166: int des_set_key(key, schedule)
167: des_cblock (*key);
168: des_key_schedule schedule;
169: {
170: static int shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0};
171: register DES_LONG c,d,t,s,t2;
172: register unsigned char *in;
173: register DES_LONG *k;
174: register int i;
175:
176: if (des_check_key)
177: {
178: if (!check_parity(key))
179: return(-1);
180:
181: if (des_is_weak_key(key))
182: return(-2);
183: }
184:
185: k=(DES_LONG *)schedule;
186: in=(unsigned char *)key;
187:
188: c2l(in,c);
189: c2l(in,d);
190:
191: /* do PC1 in 60 simple operations */
192: /* PERM_OP(d,c,t,4,0x0f0f0f0fL);
193: HPERM_OP(c,t,-2, 0xcccc0000L);
194: HPERM_OP(c,t,-1, 0xaaaa0000L);
195: HPERM_OP(c,t, 8, 0x00ff0000L);
196: HPERM_OP(c,t,-1, 0xaaaa0000L);
197: HPERM_OP(d,t,-8, 0xff000000L);
198: HPERM_OP(d,t, 8, 0x00ff0000L);
199: HPERM_OP(d,t, 2, 0x33330000L);
200: d=((d&0x00aa00aaL)<<7L)|((d&0x55005500L)>>7L)|(d&0xaa55aa55L);
201: d=(d>>8)|((c&0xf0000000L)>>4);
202: c&=0x0fffffffL; */
203:
204: /* I now do it in 47 simple operations :-)
205: * Thanks to John Fletcher ([email protected])
206: * for the inspiration. :-) */
207: PERM_OP (d,c,t,4,0x0f0f0f0fL);
208: HPERM_OP(c,t,-2,0xcccc0000L);
209: HPERM_OP(d,t,-2,0xcccc0000L);
210: PERM_OP (d,c,t,1,0x55555555L);
211: PERM_OP (c,d,t,8,0x00ff00ffL);
212: PERM_OP (d,c,t,1,0x55555555L);
213: d= (((d&0x000000ffL)<<16L)| (d&0x0000ff00L) |
214: ((d&0x00ff0000L)>>16L)|((c&0xf0000000L)>>4L));
215: c&=0x0fffffffL;
216:
217: for (i=0; i<ITERATIONS; i++)
218: {
219: if (shifts2[i])
220: { c=((c>>2L)|(c<<26L)); d=((d>>2L)|(d<<26L)); }
221: else
222: { c=((c>>1L)|(c<<27L)); d=((d>>1L)|(d<<27L)); }
223: c&=0x0fffffffL;
224: d&=0x0fffffffL;
225: /* could be a few less shifts but I am to lazy at this
226: * point in time to investigate */
227: s= des_skb[0][ (c )&0x3f ]|
228: des_skb[1][((c>> 6)&0x03)|((c>> 7L)&0x3c)]|
229: des_skb[2][((c>>13)&0x0f)|((c>>14L)&0x30)]|
230: des_skb[3][((c>>20)&0x01)|((c>>21L)&0x06) |
231: ((c>>22L)&0x38)];
232: t= des_skb[4][ (d )&0x3f ]|
233: des_skb[5][((d>> 7L)&0x03)|((d>> 8L)&0x3c)]|
234: des_skb[6][ (d>>15L)&0x3f ]|
235: des_skb[7][((d>>21L)&0x0f)|((d>>22L)&0x30)];
236:
237: /* table contained 0213 4657 */
238: t2=((t<<16L)|(s&0x0000ffffL))&0xffffffffL;
239: *(k++)=ROTATE(t2,30)&0xffffffffL;
240:
241: t2=((s>>16L)|(t&0xffff0000L));
242: *(k++)=ROTATE(t2,26)&0xffffffffL;
243: }
244: return(0);
245: }
246:
247: int _cdecl des_key_sched(key, schedule)
248: des_cblock (*key);
249: des_key_schedule schedule;
250: {
251: return(des_set_key(key,schedule));
252: }
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