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      1 /* crypto/rc2/rc2_cbc.c */
      2 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com)
      3  * All rights reserved.
      4  *
      5  * This package is an SSL implementation written
      6  * by Eric Young (eay (at) 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 (at) 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 (at) 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 (at) 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 <openssl/rc2.h>
     60 #include "rc2_locl.h"
     61 
     62 void RC2_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
     63 	     RC2_KEY *ks, unsigned char *iv, int encrypt)
     64 	{
     65 	register unsigned long tin0,tin1;
     66 	register unsigned long tout0,tout1,xor0,xor1;
     67 	register long l=length;
     68 	unsigned long tin[2];
     69 
     70 	if (encrypt)
     71 		{
     72 		c2l(iv,tout0);
     73 		c2l(iv,tout1);
     74 		iv-=8;
     75 		for (l-=8; l>=0; l-=8)
     76 			{
     77 			c2l(in,tin0);
     78 			c2l(in,tin1);
     79 			tin0^=tout0;
     80 			tin1^=tout1;
     81 			tin[0]=tin0;
     82 			tin[1]=tin1;
     83 			RC2_encrypt(tin,ks);
     84 			tout0=tin[0]; l2c(tout0,out);
     85 			tout1=tin[1]; l2c(tout1,out);
     86 			}
     87 		if (l != -8)
     88 			{
     89 			c2ln(in,tin0,tin1,l+8);
     90 			tin0^=tout0;
     91 			tin1^=tout1;
     92 			tin[0]=tin0;
     93 			tin[1]=tin1;
     94 			RC2_encrypt(tin,ks);
     95 			tout0=tin[0]; l2c(tout0,out);
     96 			tout1=tin[1]; l2c(tout1,out);
     97 			}
     98 		l2c(tout0,iv);
     99 		l2c(tout1,iv);
    100 		}
    101 	else
    102 		{
    103 		c2l(iv,xor0);
    104 		c2l(iv,xor1);
    105 		iv-=8;
    106 		for (l-=8; l>=0; l-=8)
    107 			{
    108 			c2l(in,tin0); tin[0]=tin0;
    109 			c2l(in,tin1); tin[1]=tin1;
    110 			RC2_decrypt(tin,ks);
    111 			tout0=tin[0]^xor0;
    112 			tout1=tin[1]^xor1;
    113 			l2c(tout0,out);
    114 			l2c(tout1,out);
    115 			xor0=tin0;
    116 			xor1=tin1;
    117 			}
    118 		if (l != -8)
    119 			{
    120 			c2l(in,tin0); tin[0]=tin0;
    121 			c2l(in,tin1); tin[1]=tin1;
    122 			RC2_decrypt(tin,ks);
    123 			tout0=tin[0]^xor0;
    124 			tout1=tin[1]^xor1;
    125 			l2cn(tout0,tout1,out,l+8);
    126 			xor0=tin0;
    127 			xor1=tin1;
    128 			}
    129 		l2c(xor0,iv);
    130 		l2c(xor1,iv);
    131 		}
    132 	tin0=tin1=tout0=tout1=xor0=xor1=0;
    133 	tin[0]=tin[1]=0;
    134 	}
    135 
    136 void RC2_encrypt(unsigned long *d, RC2_KEY *key)
    137 	{
    138 	int i,n;
    139 	register RC2_INT *p0,*p1;
    140 	register RC2_INT x0,x1,x2,x3,t;
    141 	unsigned long l;
    142 
    143 	l=d[0];
    144 	x0=(RC2_INT)l&0xffff;
    145 	x1=(RC2_INT)(l>>16L);
    146 	l=d[1];
    147 	x2=(RC2_INT)l&0xffff;
    148 	x3=(RC2_INT)(l>>16L);
    149 
    150 	n=3;
    151 	i=5;
    152 
    153 	p0=p1= &(key->data[0]);
    154 	for (;;)
    155 		{
    156 		t=(x0+(x1& ~x3)+(x2&x3)+ *(p0++))&0xffff;
    157 		x0=(t<<1)|(t>>15);
    158 		t=(x1+(x2& ~x0)+(x3&x0)+ *(p0++))&0xffff;
    159 		x1=(t<<2)|(t>>14);
    160 		t=(x2+(x3& ~x1)+(x0&x1)+ *(p0++))&0xffff;
    161 		x2=(t<<3)|(t>>13);
    162 		t=(x3+(x0& ~x2)+(x1&x2)+ *(p0++))&0xffff;
    163 		x3=(t<<5)|(t>>11);
    164 
    165 		if (--i == 0)
    166 			{
    167 			if (--n == 0) break;
    168 			i=(n == 2)?6:5;
    169 
    170 			x0+=p1[x3&0x3f];
    171 			x1+=p1[x0&0x3f];
    172 			x2+=p1[x1&0x3f];
    173 			x3+=p1[x2&0x3f];
    174 			}
    175 		}
    176 
    177 	d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L);
    178 	d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L);
    179 	}
    180 
    181 void RC2_decrypt(unsigned long *d, RC2_KEY *key)
    182 	{
    183 	int i,n;
    184 	register RC2_INT *p0,*p1;
    185 	register RC2_INT x0,x1,x2,x3,t;
    186 	unsigned long l;
    187 
    188 	l=d[0];
    189 	x0=(RC2_INT)l&0xffff;
    190 	x1=(RC2_INT)(l>>16L);
    191 	l=d[1];
    192 	x2=(RC2_INT)l&0xffff;
    193 	x3=(RC2_INT)(l>>16L);
    194 
    195 	n=3;
    196 	i=5;
    197 
    198 	p0= &(key->data[63]);
    199 	p1= &(key->data[0]);
    200 	for (;;)
    201 		{
    202 		t=((x3<<11)|(x3>>5))&0xffff;
    203 		x3=(t-(x0& ~x2)-(x1&x2)- *(p0--))&0xffff;
    204 		t=((x2<<13)|(x2>>3))&0xffff;
    205 		x2=(t-(x3& ~x1)-(x0&x1)- *(p0--))&0xffff;
    206 		t=((x1<<14)|(x1>>2))&0xffff;
    207 		x1=(t-(x2& ~x0)-(x3&x0)- *(p0--))&0xffff;
    208 		t=((x0<<15)|(x0>>1))&0xffff;
    209 		x0=(t-(x1& ~x3)-(x2&x3)- *(p0--))&0xffff;
    210 
    211 		if (--i == 0)
    212 			{
    213 			if (--n == 0) break;
    214 			i=(n == 2)?6:5;
    215 
    216 			x3=(x3-p1[x2&0x3f])&0xffff;
    217 			x2=(x2-p1[x1&0x3f])&0xffff;
    218 			x1=(x1-p1[x0&0x3f])&0xffff;
    219 			x0=(x0-p1[x3&0x3f])&0xffff;
    220 			}
    221 		}
    222 
    223 	d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L);
    224 	d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L);
    225 	}
    226 
    227