xref: /freebsd/crypto/openssl/crypto/des/cfb64ede.c (revision 7bd6fde3)
1 /* crypto/des/cfb64ede.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
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 (tjh@cryptsoft.com).
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 (eay@cryptsoft.com)"
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 (tjh@cryptsoft.com)"
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 #include "des_locl.h"
60 #include "e_os.h"
61 
62 /* The input and output encrypted as though 64bit cfb mode is being
63  * used.  The extra state information to record how much of the
64  * 64bit block we have used is contained in *num;
65  */
66 
67 void DES_ede3_cfb64_encrypt(const unsigned char *in, unsigned char *out,
68 			    long length, DES_key_schedule *ks1,
69 			    DES_key_schedule *ks2, DES_key_schedule *ks3,
70 			    DES_cblock *ivec, int *num, int enc)
71 	{
72 	register DES_LONG v0,v1;
73 	register long l=length;
74 	register int n= *num;
75 	DES_LONG ti[2];
76 	unsigned char *iv,c,cc;
77 
78 	iv=&(*ivec)[0];
79 	if (enc)
80 		{
81 		while (l--)
82 			{
83 			if (n == 0)
84 				{
85 				c2l(iv,v0);
86 				c2l(iv,v1);
87 
88 				ti[0]=v0;
89 				ti[1]=v1;
90 				DES_encrypt3(ti,ks1,ks2,ks3);
91 				v0=ti[0];
92 				v1=ti[1];
93 
94 				iv = &(*ivec)[0];
95 				l2c(v0,iv);
96 				l2c(v1,iv);
97 				iv = &(*ivec)[0];
98 				}
99 			c= *(in++)^iv[n];
100 			*(out++)=c;
101 			iv[n]=c;
102 			n=(n+1)&0x07;
103 			}
104 		}
105 	else
106 		{
107 		while (l--)
108 			{
109 			if (n == 0)
110 				{
111 				c2l(iv,v0);
112 				c2l(iv,v1);
113 
114 				ti[0]=v0;
115 				ti[1]=v1;
116 				DES_encrypt3(ti,ks1,ks2,ks3);
117 				v0=ti[0];
118 				v1=ti[1];
119 
120 				iv = &(*ivec)[0];
121 				l2c(v0,iv);
122 				l2c(v1,iv);
123 				iv = &(*ivec)[0];
124 				}
125 			cc= *(in++);
126 			c=iv[n];
127 			iv[n]=cc;
128 			*(out++)=c^cc;
129 			n=(n+1)&0x07;
130 			}
131 		}
132 	v0=v1=ti[0]=ti[1]=c=cc=0;
133 	*num=n;
134 	}
135 
136 #ifdef undef /* MACRO */
137 void DES_ede2_cfb64_encrypt(unsigned char *in, unsigned char *out, long length,
138 	     DES_key_schedule ks1, DES_key_schedule ks2, DES_cblock (*ivec),
139 	     int *num, int enc)
140 	{
141 	DES_ede3_cfb64_encrypt(in,out,length,ks1,ks2,ks1,ivec,num,enc);
142 	}
143 #endif
144 
145 /* This is compatible with the single key CFB-r for DES, even thought that's
146  * not what EVP needs.
147  */
148 
149 void DES_ede3_cfb_encrypt(const unsigned char *in,unsigned char *out,
150 			  int numbits,long length,DES_key_schedule *ks1,
151 			  DES_key_schedule *ks2,DES_key_schedule *ks3,
152 			  DES_cblock *ivec,int enc)
153 	{
154 	register DES_LONG d0,d1,v0,v1;
155 	register unsigned long l=length,n=((unsigned int)numbits+7)/8;
156 	register int num=numbits,i;
157 	DES_LONG ti[2];
158 	unsigned char *iv;
159 	unsigned char ovec[16];
160 
161 	if (num > 64) return;
162 	iv = &(*ivec)[0];
163 	c2l(iv,v0);
164 	c2l(iv,v1);
165 	if (enc)
166 		{
167 		while (l >= n)
168 			{
169 			l-=n;
170 			ti[0]=v0;
171 			ti[1]=v1;
172 			DES_encrypt3(ti,ks1,ks2,ks3);
173 			c2ln(in,d0,d1,n);
174 			in+=n;
175 			d0^=ti[0];
176 			d1^=ti[1];
177 			l2cn(d0,d1,out,n);
178 			out+=n;
179 			/* 30-08-94 - eay - changed because l>>32 and
180 			 * l<<32 are bad under gcc :-( */
181 			if (num == 32)
182 				{ v0=v1; v1=d0; }
183 			else if (num == 64)
184 				{ v0=d0; v1=d1; }
185 			else
186 				{
187 				iv=&ovec[0];
188 				l2c(v0,iv);
189 				l2c(v1,iv);
190 				l2c(d0,iv);
191 				l2c(d1,iv);
192 				/* shift ovec left most of the bits... */
193 				memmove(ovec,ovec+num/8,8+(num%8 ? 1 : 0));
194 				/* now the remaining bits */
195 				if(num%8 != 0)
196 					for(i=0 ; i < 8 ; ++i)
197 						{
198 						ovec[i]<<=num%8;
199 						ovec[i]|=ovec[i+1]>>(8-num%8);
200 						}
201 				iv=&ovec[0];
202 				c2l(iv,v0);
203 				c2l(iv,v1);
204 				}
205 			}
206 		}
207 	else
208 		{
209 		while (l >= n)
210 			{
211 			l-=n;
212 			ti[0]=v0;
213 			ti[1]=v1;
214 			DES_encrypt3(ti,ks1,ks2,ks3);
215 			c2ln(in,d0,d1,n);
216 			in+=n;
217 			/* 30-08-94 - eay - changed because l>>32 and
218 			 * l<<32 are bad under gcc :-( */
219 			if (num == 32)
220 				{ v0=v1; v1=d0; }
221 			else if (num == 64)
222 				{ v0=d0; v1=d1; }
223 			else
224 				{
225 				iv=&ovec[0];
226 				l2c(v0,iv);
227 				l2c(v1,iv);
228 				l2c(d0,iv);
229 				l2c(d1,iv);
230 				/* shift ovec left most of the bits... */
231 				memmove(ovec,ovec+num/8,8+(num%8 ? 1 : 0));
232 				/* now the remaining bits */
233 				if(num%8 != 0)
234 					for(i=0 ; i < 8 ; ++i)
235 						{
236 						ovec[i]<<=num%8;
237 						ovec[i]|=ovec[i+1]>>(8-num%8);
238 						}
239 				iv=&ovec[0];
240 				c2l(iv,v0);
241 				c2l(iv,v1);
242 				}
243 			d0^=ti[0];
244 			d1^=ti[1];
245 			l2cn(d0,d1,out,n);
246 			out+=n;
247 			}
248 		}
249 	iv = &(*ivec)[0];
250 	l2c(v0,iv);
251 	l2c(v1,iv);
252 	v0=v1=d0=d1=ti[0]=ti[1]=0;
253 	}
254 
255