u9fs/des.c

356 lines
16 KiB
C

#include <plan9.h>
/*
* Data Encryption Standard
* D.P.Mitchell 83/06/08.
*
* block_cipher(key, block, decrypting)
*/
static long ip_low(char [8]);
static long ip_high(char [8]);
static void fp(long, long, char[8]);
extern int chatty9p;
/*
* Tables for Combined S and P Boxes
*/
static long s0p[] = {
0x00410100,0x00010000,0x40400000,0x40410100,0x00400000,0x40010100,0x40010000,0x40400000,
0x40010100,0x00410100,0x00410000,0x40000100,0x40400100,0x00400000,0x00000000,0x40010000,
0x00010000,0x40000000,0x00400100,0x00010100,0x40410100,0x00410000,0x40000100,0x00400100,
0x40000000,0x00000100,0x00010100,0x40410000,0x00000100,0x40400100,0x40410000,0x00000000,
0x00000000,0x40410100,0x00400100,0x40010000,0x00410100,0x00010000,0x40000100,0x00400100,
0x40410000,0x00000100,0x00010100,0x40400000,0x40010100,0x40000000,0x40400000,0x00410000,
0x40410100,0x00010100,0x00410000,0x40400100,0x00400000,0x40000100,0x40010000,0x00000000,
0x00010000,0x00400000,0x40400100,0x00410100,0x40000000,0x40410000,0x00000100,0x40010100,
};
static long s1p[] = {
0x08021002,0x00000000,0x00021000,0x08020000,0x08000002,0x00001002,0x08001000,0x00021000,
0x00001000,0x08020002,0x00000002,0x08001000,0x00020002,0x08021000,0x08020000,0x00000002,
0x00020000,0x08001002,0x08020002,0x00001000,0x00021002,0x08000000,0x00000000,0x00020002,
0x08001002,0x00021002,0x08021000,0x08000002,0x08000000,0x00020000,0x00001002,0x08021002,
0x00020002,0x08021000,0x08001000,0x00021002,0x08021002,0x00020002,0x08000002,0x00000000,
0x08000000,0x00001002,0x00020000,0x08020002,0x00001000,0x08000000,0x00021002,0x08001002,
0x08021000,0x00001000,0x00000000,0x08000002,0x00000002,0x08021002,0x00021000,0x08020000,
0x08020002,0x00020000,0x00001002,0x08001000,0x08001002,0x00000002,0x08020000,0x00021000,
};
static long s2p[] = {
0x20800000,0x00808020,0x00000020,0x20800020,0x20008000,0x00800000,0x20800020,0x00008020,
0x00800020,0x00008000,0x00808000,0x20000000,0x20808020,0x20000020,0x20000000,0x20808000,
0x00000000,0x20008000,0x00808020,0x00000020,0x20000020,0x20808020,0x00008000,0x20800000,
0x20808000,0x00800020,0x20008020,0x00808000,0x00008020,0x00000000,0x00800000,0x20008020,
0x00808020,0x00000020,0x20000000,0x00008000,0x20000020,0x20008000,0x00808000,0x20800020,
0x00000000,0x00808020,0x00008020,0x20808000,0x20008000,0x00800000,0x20808020,0x20000000,
0x20008020,0x20800000,0x00800000,0x20808020,0x00008000,0x00800020,0x20800020,0x00008020,
0x00800020,0x00000000,0x20808000,0x20000020,0x20800000,0x20008020,0x00000020,0x00808000,
};
static long s3p[] = {
0x00080201,0x02000200,0x00000001,0x02080201,0x00000000,0x02080000,0x02000201,0x00080001,
0x02080200,0x02000001,0x02000000,0x00000201,0x02000001,0x00080201,0x00080000,0x02000000,
0x02080001,0x00080200,0x00000200,0x00000001,0x00080200,0x02000201,0x02080000,0x00000200,
0x00000201,0x00000000,0x00080001,0x02080200,0x02000200,0x02080001,0x02080201,0x00080000,
0x02080001,0x00000201,0x00080000,0x02000001,0x00080200,0x02000200,0x00000001,0x02080000,
0x02000201,0x00000000,0x00000200,0x00080001,0x00000000,0x02080001,0x02080200,0x00000200,
0x02000000,0x02080201,0x00080201,0x00080000,0x02080201,0x00000001,0x02000200,0x00080201,
0x00080001,0x00080200,0x02080000,0x02000201,0x00000201,0x02000000,0x02000001,0x02080200,
};
static long s4p[] = {
0x01000000,0x00002000,0x00000080,0x01002084,0x01002004,0x01000080,0x00002084,0x01002000,
0x00002000,0x00000004,0x01000004,0x00002080,0x01000084,0x01002004,0x01002080,0x00000000,
0x00002080,0x01000000,0x00002004,0x00000084,0x01000080,0x00002084,0x00000000,0x01000004,
0x00000004,0x01000084,0x01002084,0x00002004,0x01002000,0x00000080,0x00000084,0x01002080,
0x01002080,0x01000084,0x00002004,0x01002000,0x00002000,0x00000004,0x01000004,0x01000080,
0x01000000,0x00002080,0x01002084,0x00000000,0x00002084,0x01000000,0x00000080,0x00002004,
0x01000084,0x00000080,0x00000000,0x01002084,0x01002004,0x01002080,0x00000084,0x00002000,
0x00002080,0x01002004,0x01000080,0x00000084,0x00000004,0x00002084,0x01002000,0x01000004,
};
static long s5p[] = {
0x10000008,0x00040008,0x00000000,0x10040400,0x00040008,0x00000400,0x10000408,0x00040000,
0x00000408,0x10040408,0x00040400,0x10000000,0x10000400,0x10000008,0x10040000,0x00040408,
0x00040000,0x10000408,0x10040008,0x00000000,0x00000400,0x00000008,0x10040400,0x10040008,
0x10040408,0x10040000,0x10000000,0x00000408,0x00000008,0x00040400,0x00040408,0x10000400,
0x00000408,0x10000000,0x10000400,0x00040408,0x10040400,0x00040008,0x00000000,0x10000400,
0x10000000,0x00000400,0x10040008,0x00040000,0x00040008,0x10040408,0x00040400,0x00000008,
0x10040408,0x00040400,0x00040000,0x10000408,0x10000008,0x10040000,0x00040408,0x00000000,
0x00000400,0x10000008,0x10000408,0x10040400,0x10040000,0x00000408,0x00000008,0x10040008,
};
static long s6p[] = {
0x00000800,0x00000040,0x00200040,0x80200000,0x80200840,0x80000800,0x00000840,0x00000000,
0x00200000,0x80200040,0x80000040,0x00200800,0x80000000,0x00200840,0x00200800,0x80000040,
0x80200040,0x00000800,0x80000800,0x80200840,0x00000000,0x00200040,0x80200000,0x00000840,
0x80200800,0x80000840,0x00200840,0x80000000,0x80000840,0x80200800,0x00000040,0x00200000,
0x80000840,0x00200800,0x80200800,0x80000040,0x00000800,0x00000040,0x00200000,0x80200800,
0x80200040,0x80000840,0x00000840,0x00000000,0x00000040,0x80200000,0x80000000,0x00200040,
0x00000000,0x80200040,0x00200040,0x00000840,0x80000040,0x00000800,0x80200840,0x00200000,
0x00200840,0x80000000,0x80000800,0x80200840,0x80200000,0x00200840,0x00200800,0x80000800,
};
static long s7p[] = {
0x04100010,0x04104000,0x00004010,0x00000000,0x04004000,0x00100010,0x04100000,0x04104010,
0x00000010,0x04000000,0x00104000,0x00004010,0x00104010,0x04004010,0x04000010,0x04100000,
0x00004000,0x00104010,0x00100010,0x04004000,0x04104010,0x04000010,0x00000000,0x00104000,
0x04000000,0x00100000,0x04004010,0x04100010,0x00100000,0x00004000,0x04104000,0x00000010,
0x00100000,0x00004000,0x04000010,0x04104010,0x00004010,0x04000000,0x00000000,0x00104000,
0x04100010,0x04004010,0x04004000,0x00100010,0x04104000,0x00000010,0x00100010,0x04004000,
0x04104010,0x00100000,0x04100000,0x04000010,0x00104000,0x00004010,0x04004010,0x04100000,
0x00000010,0x04104000,0x00104010,0x00000000,0x04000000,0x04100010,0x00004000,0x00104010,
};
/*
* DES electronic codebook encryption of one block
*/
void
block_cipher(char expanded_key[128], char text[8], int decrypting)
{
char *key;
long crypto, temp, right, left;
int i, key_offset;
key = expanded_key;
left = ip_low(text);
right = ip_high(text);
if (decrypting) {
key_offset = 16;
key = key + 128 - 8;
} else
key_offset = 0;
for (i = 0; i < 16; i++) {
temp = (right << 1) | ((right >> 31) & 1);
crypto = s0p[(temp & 0x3f) ^ *key++];
crypto |= s1p[((temp >> 4) & 0x3f) ^ *key++];
crypto |= s2p[((temp >> 8) & 0x3f) ^ *key++];
crypto |= s3p[((temp >> 12) & 0x3f) ^ *key++];
crypto |= s4p[((temp >> 16) & 0x3f) ^ *key++];
crypto |= s5p[((temp >> 20) & 0x3f) ^ *key++];
crypto |= s6p[((temp >> 24) & 0x3f) ^ *key++];
temp = ((right & 1) << 5) | ((right >> 27) & 0x1f);
crypto |= s7p[temp ^ *key++];
temp = left;
left = right;
right = temp ^ crypto;
key -= key_offset;
}
/*
* standard final permutation (IPI)
* left and right are reversed here
*/
fp(right, left, text);
}
/*
* Initial Permutation
*/
static long iptab[] = {
0x00000000, 0x00008000, 0x00000000, 0x00008000,
0x00000080, 0x00008080, 0x00000080, 0x00008080
};
static long
ip_low(char block[8])
{
int i;
long l;
l = 0;
for(i = 0; i < 8; i++){
l |= iptab[(block[i] >> 4) & 7] >> i;
l |= iptab[block[i] & 7] << (16 - i);
}
return l;
}
static long
ip_high(char block[8])
{
int i;
long l;
l = 0;
for(i = 0; i < 8; i++){
l |= iptab[(block[i] >> 5) & 7] >> i;
l |= iptab[(block[i] >> 1) & 7] << (16 - i);
}
return l;
}
/*
* Final Permutation
*/
static unsigned long fptab[] = {
0x00000000,0x80000000,0x00800000,0x80800000,0x00008000,0x80008000,0x00808000,0x80808000,
0x00000080,0x80000080,0x00800080,0x80800080,0x00008080,0x80008080,0x00808080,0x80808080,
};
static void
fp(long left, long right, char text[8])
{
unsigned long ta[2], t, v[2];
int i, j, sh;
ta[0] = right;
ta[1] = left;
v[0] = v[1] = 0;
for(i = 0; i < 2; i++){
t = ta[i];
sh = i;
for(j = 0; j < 4; j++){
v[1] |= fptab[t & 0xf] >> sh;
t >>= 4;
v[0] |= fptab[t & 0xf] >> sh;
t >>= 4;
sh += 2;
}
}
for(i = 0; i < 2; i++)
for(j = 0; j < 4; j++){
*text++ = v[i];
v[i] >>= 8;
}
}
/*
* Key set-up
*/
static uchar keyexpand[][15][2] = {
{ 3, 2, 9, 8, 18, 8, 27, 32, 33, 2, 42, 16, 48, 8, 65, 16,
74, 2, 80, 2, 89, 4, 99, 16, 104, 4, 122, 32, 0, 0, },
{ 1, 4, 8, 1, 18, 4, 25, 32, 34, 32, 41, 8, 50, 8, 59, 32,
64, 16, 75, 4, 90, 1, 97, 16, 106, 2, 112, 2, 123, 1, },
{ 2, 1, 19, 8, 35, 1, 40, 1, 50, 4, 57, 32, 75, 2, 80, 32,
89, 1, 96, 16, 107, 4, 120, 8, 0, 0, 0, 0, 0, 0, },
{ 4, 32, 20, 2, 31, 4, 37, 32, 47, 1, 54, 1, 63, 2, 68, 1,
78, 4, 84, 8, 101, 16, 108, 4, 119, 16, 126, 8, 0, 0, },
{ 5, 4, 15, 4, 21, 32, 31, 1, 38, 1, 47, 2, 53, 2, 68, 8,
85, 16, 92, 4, 103, 16, 108, 32, 118, 32, 124, 2, 0, 0, },
{ 15, 2, 21, 2, 39, 8, 46, 16, 55, 32, 61, 1, 71, 16, 76, 32,
86, 32, 93, 4, 102, 2, 108, 16, 117, 8, 126, 1, 0, 0, },
{ 14, 16, 23, 32, 29, 1, 38, 8, 52, 2, 63, 4, 70, 2, 76, 16,
85, 8, 100, 1, 110, 4, 116, 8, 127, 8, 0, 0, 0, 0, },
{ 1, 8, 8, 32, 17, 1, 24, 16, 35, 4, 50, 1, 57, 16, 67, 8,
83, 1, 88, 1, 98, 4, 105, 32, 114, 32, 123, 2, 0, 0, },
{ 0, 1, 11, 16, 16, 4, 35, 2, 40, 32, 49, 1, 56, 16, 65, 2,
74, 16, 80, 8, 99, 8, 115, 1, 121, 4, 0, 0, 0, 0, },
{ 9, 16, 18, 2, 24, 2, 33, 4, 43, 16, 48, 4, 66, 32, 73, 8,
82, 8, 91, 32, 97, 2, 106, 16, 112, 8, 122, 1, 0, 0, },
{ 14, 32, 21, 4, 30, 2, 36, 16, 45, 8, 60, 1, 69, 2, 87, 8,
94, 16, 103, 32, 109, 1, 118, 8, 124, 32, 0, 0, 0, 0, },
{ 7, 4, 14, 2, 20, 16, 29, 8, 44, 1, 54, 4, 60, 8, 71, 8,
78, 16, 87, 32, 93, 1, 102, 8, 116, 2, 125, 4, 0, 0, },
{ 7, 2, 12, 1, 22, 4, 28, 8, 45, 16, 52, 4, 63, 16, 70, 8,
84, 2, 95, 4, 101, 32, 111, 1, 118, 1, 0, 0, 0, 0, },
{ 6, 16, 13, 16, 20, 4, 31, 16, 36, 32, 46, 32, 53, 4, 62, 2,
69, 32, 79, 1, 86, 1, 95, 2, 101, 2, 119, 8, 0, 0, },
{ 0, 32, 10, 8, 19, 32, 25, 2, 34, 16, 40, 8, 59, 8, 66, 2,
72, 2, 81, 4, 91, 16, 96, 4, 115, 2, 121, 8, 0, 0, },
{ 3, 16, 10, 4, 17, 32, 26, 32, 33, 8, 42, 8, 51, 32, 57, 2,
67, 4, 82, 1, 89, 16, 98, 2, 104, 2, 113, 4, 120, 1, },
{ 1, 16, 11, 8, 27, 1, 32, 1, 42, 4, 49, 32, 58, 32, 67, 2,
72, 32, 81, 1, 88, 16, 99, 4, 114, 1, 0, 0, 0, 0, },
{ 6, 32, 12, 2, 23, 4, 29, 32, 39, 1, 46, 1, 55, 2, 61, 2,
70, 4, 76, 8, 93, 16, 100, 4, 111, 16, 116, 32, 0, 0, },
{ 6, 2, 13, 32, 23, 1, 30, 1, 39, 2, 45, 2, 63, 8, 77, 16,
84, 4, 95, 16, 100, 32, 110, 32, 117, 4, 127, 4, 0, 0, },
{ 4, 1, 13, 2, 31, 8, 38, 16, 47, 32, 53, 1, 62, 8, 68, 32,
78, 32, 85, 4, 94, 2, 100, 16, 109, 8, 127, 2, 0, 0, },
{ 5, 16, 15, 32, 21, 1, 30, 8, 44, 2, 55, 4, 61, 32, 68, 16,
77, 8, 92, 1, 102, 4, 108, 8, 126, 16, 0, 0, 0, 0, },
{ 2, 8, 9, 1, 16, 16, 27, 4, 42, 1, 49, 16, 58, 2, 75, 1,
80, 1, 90, 4, 97, 32, 106, 32, 113, 8, 120, 32, 0, 0, },
{ 2, 4, 8, 4, 27, 2, 32, 32, 41, 1, 48, 16, 59, 4, 66, 16,
72, 8, 91, 8, 107, 1, 112, 1, 123, 16, 0, 0, 0, 0, },
{ 3, 8, 10, 2, 16, 2, 25, 4, 35, 16, 40, 4, 59, 2, 65, 8,
74, 8, 83, 32, 89, 2, 98, 16, 104, 8, 121, 16, 0, 0, },
{ 4, 2, 13, 4, 22, 2, 28, 16, 37, 8, 52, 1, 62, 4, 79, 8,
86, 16, 95, 32, 101, 1, 110, 8, 126, 32, 0, 0, 0, 0, },
{ 5, 32, 12, 16, 21, 8, 36, 1, 46, 4, 52, 8, 70, 16, 79, 32,
85, 1, 94, 8, 108, 2, 119, 4, 126, 2, 0, 0, 0, 0, },
{ 5, 2, 14, 4, 20, 8, 37, 16, 44, 4, 55, 16, 60, 32, 76, 2,
87, 4, 93, 32, 103, 1, 110, 1, 119, 2, 124, 1, 0, 0, },
{ 7, 32, 12, 4, 23, 16, 28, 32, 38, 32, 45, 4, 54, 2, 60, 16,
71, 1, 78, 1, 87, 2, 93, 2, 111, 8, 118, 16, 125, 16, },
{ 1, 1, 11, 32, 17, 2, 26, 16, 32, 8, 51, 8, 64, 2, 73, 4,
83, 16, 88, 4, 107, 2, 112, 32, 122, 8, 0, 0, 0, 0, },
{ 0, 4, 9, 32, 18, 32, 25, 8, 34, 8, 43, 32, 49, 2, 58, 16,
74, 1, 81, 16, 90, 2, 96, 2, 105, 4, 115, 16, 122, 4, },
{ 2, 2, 19, 1, 24, 1, 34, 4, 41, 32, 50, 32, 57, 8, 64, 32,
73, 1, 80, 16, 91, 4, 106, 1, 113, 16, 123, 8, 0, 0, },
{ 3, 4, 10, 16, 16, 8, 35, 8, 51, 1, 56, 1, 67, 16, 72, 4,
91, 2, 96, 32, 105, 1, 112, 16, 121, 2, 0, 0, 0, 0, },
{ 4, 16, 15, 1, 22, 1, 31, 2, 37, 2, 55, 8, 62, 16, 69, 16,
76, 4, 87, 16, 92, 32, 102, 32, 109, 4, 118, 2, 125, 32, },
{ 6, 4, 23, 8, 30, 16, 39, 32, 45, 1, 54, 8, 70, 32, 77, 4,
86, 2, 92, 16, 101, 8, 116, 1, 125, 2, 0, 0, 0, 0, },
{ 4, 4, 13, 1, 22, 8, 36, 2, 47, 4, 53, 32, 63, 1, 69, 8,
84, 1, 94, 4, 100, 8, 117, 16, 127, 32, 0, 0, 0, 0, },
{ 3, 32, 8, 16, 19, 4, 34, 1, 41, 16, 50, 2, 56, 2, 67, 1,
72, 1, 82, 4, 89, 32, 98, 32, 105, 8, 114, 8, 121, 1, },
{ 1, 32, 19, 2, 24, 32, 33, 1, 40, 16, 51, 4, 64, 8, 83, 8,
99, 1, 104, 1, 114, 4, 120, 4, 0, 0, 0, 0, 0, 0, },
{ 8, 2, 17, 4, 27, 16, 32, 4, 51, 2, 56, 32, 66, 8, 75, 32,
81, 2, 90, 16, 96, 8, 115, 8, 122, 2, 0, 0, 0, 0, },
{ 2, 16, 18, 1, 25, 16, 34, 2, 40, 2, 49, 4, 59, 16, 66, 4,
73, 32, 82, 32, 89, 8, 98, 8, 107, 32, 113, 2, 123, 4, },
{ 7, 1, 13, 8, 28, 1, 38, 4, 44, 8, 61, 16, 71, 32, 77, 1,
86, 8, 100, 2, 111, 4, 117, 32, 124, 16, 0, 0, 0, 0, },
{ 12, 8, 29, 16, 36, 4, 47, 16, 52, 32, 62, 32, 68, 2, 79, 4,
85, 32, 95, 1, 102, 1, 111, 2, 117, 2, 126, 4, 0, 0, },
{ 5, 1, 15, 16, 20, 32, 30, 32, 37, 4, 46, 2, 52, 16, 61, 8,
70, 1, 79, 2, 85, 2, 103, 8, 110, 16, 119, 32, 124, 4, },
{ 0, 16, 9, 2, 18, 16, 24, 8, 43, 8, 59, 1, 65, 4, 75, 16,
80, 4, 99, 2, 104, 32, 113, 1, 123, 32, 0, 0, 0, 0, },
{ 10, 32, 17, 8, 26, 8, 35, 32, 41, 2, 50, 16, 56, 8, 66, 1,
73, 16, 82, 2, 88, 2, 97, 4, 107, 16, 112, 4, 121, 32, },
{ 0, 2, 11, 1, 16, 1, 26, 4, 33, 32, 42, 32, 49, 8, 58, 8,
65, 1, 72, 16, 83, 4, 98, 1, 105, 16, 114, 2, 0, 0, },
{ 8, 8, 27, 8, 43, 1, 48, 1, 58, 4, 64, 4, 83, 2, 88, 32,
97, 1, 104, 16, 115, 4, 122, 16, 0, 0, 0, 0, 0, 0, },
{ 5, 8, 14, 1, 23, 2, 29, 2, 47, 8, 54, 16, 63, 32, 68, 4,
79, 16, 84, 32, 94, 32, 101, 4, 110, 2, 116, 16, 127, 1, },
{ 4, 8, 15, 8, 22, 16, 31, 32, 37, 1, 46, 8, 60, 2, 69, 4,
78, 2, 84, 16, 93, 8, 108, 1, 118, 4, 0, 0, 0, 0, },
{ 7, 16, 14, 8, 28, 2, 39, 4, 45, 32, 55, 1, 62, 1, 76, 1,
86, 4, 92, 8, 109, 16, 116, 4, 125, 1, 0, 0, 0, 0, },
{ 1, 2, 11, 4, 26, 1, 33, 16, 42, 2, 48, 2, 57, 4, 64, 1,
74, 4, 81, 32, 90, 32, 97, 8, 106, 8, 115, 32, 120, 16, },
{ 2, 32, 11, 2, 16, 32, 25, 1, 32, 16, 43, 4, 58, 1, 75, 8,
91, 1, 96, 1, 106, 4, 113, 32, 0, 0, 0, 0, 0, 0, },
{ 3, 1, 9, 4, 19, 16, 24, 4, 43, 2, 48, 32, 57, 1, 67, 32,
73, 2, 82, 16, 88, 8, 107, 8, 120, 2, 0, 0, 0, 0, },
{ 0, 8, 10, 1, 17, 16, 26, 2, 32, 2, 41, 4, 51, 16, 56, 4,
65, 32, 74, 32, 81, 8, 90, 8, 99, 32, 105, 2, 114, 16, },
{ 6, 1, 20, 1, 30, 4, 36, 8, 53, 16, 60, 4, 69, 1, 78, 8,
92, 2, 103, 4, 109, 32, 119, 1, 125, 8, 0, 0, 0, 0, },
{ 7, 8, 21, 16, 28, 4, 39, 16, 44, 32, 54, 32, 61, 4, 71, 4,
77, 32, 87, 1, 94, 1, 103, 2, 109, 2, 124, 8, 0, 0, },
{ 6, 8, 12, 32, 22, 32, 29, 4, 38, 2, 44, 16, 53, 8, 71, 2,
77, 2, 95, 8, 102, 16, 111, 32, 117, 1, 127, 16, 0, 0, }
};
void
key_setup(char key[DESKEYLEN], char *ek)
{
int i, j, k, mask;
uchar (*x)[2];
memset(ek, 0, 128);
x = keyexpand[0];
for(i = 0; i < 7; i++){
k = key[i];
for(mask = 0x80; mask; mask >>= 1){
if(k & mask)
for(j = 0; j < 15; j++)
ek[x[j][0]] |= x[j][1];
x += 15;
}
}
}