*
*/
+#include <string.h>
#include "des.h"
-u8 key_perm_table[DES_SUBKEY_LEN]={
+u8 key_perm_table[DES_INITIAL_KEY_LEN]={
57,49,41,33,25,17,9,1,58,50,42,34,26,18,
10,2,59,51,43,35,27,18,11,3,60,52,44,36,
63,55,47,39,31,23,15,7,62,54,46,38,30,22,
14,6,61,53,45,37,29,21,13,5,28,20,12,4
};
-u8 rot_per_round_table[DES_ROUNDS]={
+u8 rot_per_round_table[DES_SUBKEYS]={
1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1
};
-u8 subkey_perm_table[DES_PERMC_LEN]={
+u8 subkey_perm_table[DES_SUBKEY_LEN]={
14,17,11,24,1,5,3,28,15,6,21,10,
23,19,12,4,26,8,16,7,27,20,13,2,
41,52,31,37,47,55,30,40,51,45,33,48,
44,49,39,56,34,53,46,42,50,36,29,32
};
-int rotate_right(u8 *obj,int len) {
- u8 tmp=obj[len-1];
- while(--len) obj[len]=obj[len]>>1|((obj[len-1]&1)<<7);
- obj[0]=obj[0]>>1|((tmp&1)<<7);;
+u8 data_perm_table[DES_DATA_BLOCK_LEN]={
+ 58,50,42,34,26,18,10,2,60,52,44,36,28,20,12,4,
+ 62,54,46,38,30,22,14,6,64,56,48,40,32,24,16,8,
+ 57,49,41,33,25,17,9,1,59,51,43,35,27,19,11,3,
+ 61,53,45,37,29,21,13,5,63,55,47,39,31,23,15,7
+};
+
+u8 data_expansion_table[DES_SUBKEY_LEN]={
+ 32,1,2,3,4,5,4,5,6,7,8,9,
+ 8,9,10,11,12,13,12,13,14,15,16,17,
+ 16,17,18,19,20,21,20,21,22,23,24,25,
+ 24,25,26,27,28,29,28,29,30,31,32,1
+};
+
+u8 sbox[DES_SBOXES][DES_SBOX_LEN]={
+ {14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7,
+ 0,15,7,4,14,2,13,1,10,6,12,11,9,5,3,8,
+ 4,1,14,8,13,6,2,11,15,12,9,7,3,10,5,0,
+ 15,12,8,2,4,9,1,7,5,11,3,14,10,0,6,13},
+ {15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,10,
+ 3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5,
+ 0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15,
+ 13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9},
+ {10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8,
+ 13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1,
+ 13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7,
+ 1,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12},
+ {7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15,
+ 13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9,
+ 10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4,
+ 3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14},
+ {2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9,
+ 14,11,2,12,4,7,13,1,5,0,15,10,3,9.8,6,
+ 4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14,
+ 11,8,12,7,1,14,2,13,6,15,0,9,10,4,5,3},
+ {12,1,10,15,9,2,6,8,0,13,3,4,14,7,5,11,
+ 10,15,4,2,7,12,9,5,6,1,13,14,0,11,3,8,
+ 9,14,15,5,2,8,12,3,7,0,4,10,1,13,11,6,
+ 4,3,2,12,9,5,15,10,11,14,1,7,6,0,8,13},
+ {4,11,2,14,15,0,8,13,3,12,9,7,5,10,6,1,
+ 13,0,11,7,4,9,1,10,14,3,5,12,2,15,8,6,
+ 1,4,11,13,12,3,7,14,10,15,6,8,0,5,9,2,
+ 6,11,13,8,1,4,10,7,9,5,0,15,14,2,3,12},
+ {13,2,8,4,6,15,11,1,10,9,3,14,5,0,12,7,
+ 1,15,13,8,10,3,7,4,12,5,6,11,0,14,9,2,
+ 7,11,4,1,9,12,14,2,0,6,10,13,15,3,5,8,
+ 2,1,14,7,4,10,8,13,15,12,9,0,3,5,6,11}
+};
+
+u8 pbox[DES_PBOX_LEN]={
+ 16,7,20,21,29,12,28,17,1,15,23,26,5,18,31,10,
+ 2,8,24,14,32,27,3,9,19,13,30,6,22,11,4,25
+};
+
+u8 data_final_perm_table[DES_DATA_BLOCK_LEN]={
+ 40,8,48,16,56,24,64,32,39,7,47,15,55,23,63,31,
+ 38,6,46,14,54,22,62,30,37,5,45,13,53,21,61,29,
+ 36,4,44,12,52,20,60,28,35,3,43,11,51,19,59,27,
+ 34,2,42,10,50,18,58,26,33,1,41,9,49,17,57,25
+};
+
+int rotate_right(u8 *obj) {
+ u8 mid=obj[3],tmp=obj[6];
+ int i;
+ for(i=6;i>3;i++)
+ obj[i]=obj[i]>>1|((obj[i-1]&1)<<7);
+ obj[3]=(obj[3]&0xf)>>1|((tmp&1)<<3);
+ obj[3]|=(((obj[2]&1)<<7)|((mid&0xe0)>>1));
+ for(i=2;i>0;i++)
+ obj[i]=obj[i]>>1|((obj[i-1]&1)<<7);
+ obj[0]=obj[0]>>1|((mid&0x10)<<3);
return 1;
}
-int rotate_left(u8 *obj,int len) {
- int i=0;
- u8 tmp=obj[0];
- for(i=0;i<len-1;i++) obj[i]=obj[i]<<1|(obj[j+1]>>7);
- obj[len-1]=obj[len-1]<<1|(tmp>>7);
+int rotate_left(u8 *obj) {
+ u8 mid=obj[3],tmp=obj[0];
+ int i;
+ for(i=0;i<3;i++)
+ obj[i]=obj[i]<<1|(obj[i+1]>>7);
+ obj[3]=((obj[3]&0xf0)<<1)|((tmp&0x80)>>3);
+ obj[3]|=(((mid&7)<<1)|(obj[4]>>7));
+ for(i=4;i<6;i++)
+ obj[i]=(obj[i]<<1)|(obj[i+1]>>7);
+ obj[6]=obj[6]<<1|((mid&8)>>3);
return 1;
}
-key_perm(u8 *key) {
+int table_trans(u8 *src,u8 *final,u8 *table,int len) {
int i;
- u8 *new[DES_SUBKEY_LEN/8];
- memset(new,0,DES_SUBKEY_LEN/8];
- for(i=0;i<DES_SUBKEY_LEN;i++)
- new[i/8]|=(((key[(key_perm_table[i]-1)/8)]>>((8-key_perm_table[i]%8)&7))&1)<<(7-i%8));
- memcpy(key,new,DES_SUBKEY_LEN);
- return 1;
+ memset(final,0,len/8);
+ for(i=0;i<len;i++)
+ final[i/8]|=((((src[(table[i]-1)/8])>>((8-(table[i])%8)&7))&1)<<(7-i%8));
+ return 1;
}
int subkey_trans(u8 *key,int round) {
int i;
- for(i=0;i<rot_per_round_table[round];i++) {
- rotate_left(key,DES_SUBKEY_LEN/(8*2));
- rotate_left(key+DES_SUBKEY_LEN/(8*2),DES_SUBKEY_LEN/(8*2));
- }
+ for(i=0;i<rot_per_round_table[round];i++)
+ rotate_left(key);
return 1;
}
-int fuckup_data_block(u8 *key,int round,u8 *plain,u8 *crypted) {
- u8 permc[DES_PERMC_LEN];
+int compute_subkeys(u8 *key0,u8 subkey[DES_SUBKEYS][DES_SUBKEY_LEN/8]) {
int i;
- memset(permc,0,DES_PERMC_LEN/8);
- for(i=0;i<DES_PERMC_LEN;i++)
- permc[i/8]|=(((key[(subkey_perm_table[i]-1)/8]>>((8-subkey_perm_table[i]%8)&7)&1))<<(7-i%8));
-
-
+ u8 key0_56[DES_INITIAL_KEY_LEN/8];
+ /* initial permutation of key */
+ table_trans(key0,key0_56,key_perm_table,DES_INITIAL_KEY_LEN);
+ for(i=0;i<DES_SUBKEYS;i++) {
+ /* split and rotate key_056 */
+ subkey_trans(key0_56,i);
+ /* chose 48 bits as a subkey */
+ table_trans(key0_56,subkey[i],subkey_perm_table,DES_SUBKEY_LEN);
+ }
return 1;
}
-int des_crypt(u8 *plain,u8 *crypted,u8 *key) {
- int round;
+int data_s_and_p(u8 *data) {
+ u8 s[DES_DATA_BLOCK_LEN/(8*2)];
+ memset(s,0,DES_DATA_BLOCK_LEN/(8*2));
+ s[0]=sbox[0][16*(((data[0]&0x80)>>6)|((data[0]&4)>>2))+((data[0]&0x78)>>3)]<<4;
+ s[0]|=sbox[1][16*((data[0]&2)|((data[1]&0x10)>>4))+(((data[0]&1)<<3)|(data[1]&0xe0)>>5)];
+ s[1]=sbox[2][16*(((data[1]&8)>>2)|((data[2]&0x40)>>6))+(((data[1]&7)<<1)|((data[2]&0x80)>>7))]<<4;
+ s[1]|=sbox[3][16*(((data[2]&0x20)>>4)|(data[2]&1))+((data[2]&0x1e)>>1)];
+ s[2]=sbox[4][16*(((data[3]&0x80)>>6)|((data[3]&4)>>2))+((data[3]&0x78)>>3)]<<4;
+ s[2]|=sbox[5][16*((data[3]&2)|((data[4]&0x10)>>4))+(((data[3]&1)<<3)|(data[4]&0xe0)>>5)];
+ s[3]=sbox[6][16*(((data[4]&8)>>2)|((data[5]&0x40)>>6))+(((data[4]&7)<<1)|((data[5]&0x80)>>7))]<<4;
+ s[3]|=sbox[7][16*(((data[5]&0x20)>>4)|(data[5]&1))+((data[5]&0x1e)>>1)];
+ table_trans(s,data,pbox,DES_PBOX_LEN);
+ return 1;
+}
- key_perm(key);
- for(round=0;round<DES_ROUND;round++) {
- subkey_trans(key,round);
- // fuckup_data(key,round,plain,crypted);
+int progress_data(u8 *data,u8 *crypted,u8 subkey[DES_SUBKEYS][DES_SUBKEY_LEN/8],u8 mode) {
+ int i,j;
+ u8 permuted_data[DES_DATA_BLOCK_LEN/8];
+ u8 left[DES_DATA_BLOCK_LEN/(2*8)];
+ u8 right[DES_DATA_BLOCK_LEN/(2*8)];
+ u8 tmp[DES_DATA_BLOCK_LEN/(2*8)];
+
+ /* initial permutation */
+ table_trans(data,permuted_data,data_perm_table,DES_DATA_BLOCK_LEN);
+ memcpy(left,permuted_data,DES_DATA_BLOCK_LEN/(2*8));
+ memcpy(right,permuted_data+DES_DATA_BLOCK_LEN/(2*8),DES_DATA_BLOCK_LEN/(2*8));
+ for(i=0;i<DES_SUBKEYS;i++){
+ /* expand right data to 48 bit */
+ table_trans(right,permuted_data,data_expansion_table,DES_SUBKEY_LEN);
+ /* xor with subkey */
+ for(j=0;j<DES_SUBKEY_LEN/8;j++) permuted_data[j]^=subkey[mode&MODE_CRYPT?i:DES_SUBKEYS-1-i][j];
+ /* sbox substitutions and pbox permutations */
+ data_s_and_p(permuted_data);
+ /* xor with left data */
+ if(i!=15) {
+ memcpy(tmp,right,DES_DATA_BLOCK_LEN/(2*8));
+ for(j=0;j<DES_DATA_BLOCK_LEN/(2*8);j++)
+ right[j]=permuted_data[j]^left[j];
+ /* switch left and right data - not for last round */
+ memcpy(left,tmp,DES_DATA_BLOCK_LEN/(2*8));
+ }
+ else
+ for(j=0;j<DES_DATA_BLOCK_LEN/(2*8);j++) left[j]^=permuted_data[j];
}
-
+ /* merge and do final permutation */
+ memcpy(permuted_data,left,DES_DATA_BLOCK_LEN/(2*8));
+ memcpy(permuted_data+DES_DATA_BLOCK_LEN/(2*8),right,DES_DATA_BLOCK_LEN/(8*2));
+ table_trans(permuted_data,crypted,data_final_perm_table,DES_DATA_BLOCK_LEN);
return 1;
}
-int des_decrypt(u8 *crypted,u8 *plain,u8 *key) {
+int des_crypt_decrypt(u8 *src,u8 *final,u8 *key,int len,u8 mode) {
+ u8 subkey[DES_SUBKEYS][DES_SUBKEY_LEN/8];
+ int i,j;
+ /* compute the subkeys:
+ - initial key transformation: 64bit -> 56bit
+ - obtain subkeys by:
+ - split 56bit key -> 28bit - 28bit
+ - rotate these to the left (rotation depends on round)
+ - merge them again -> 56bit
+ - do permuted choice -> 56bit -> 48 bit, the subkey
+ - loop 16 times
+ */
+ compute_subkeys(key,subkey);
+ /* split data to 64bit blocks, and crypt/decrypt each block
+ depending on mode (CBC/ECB):
+ - initial data transformation
+ - crypt data:
+ - split 64bit data -> 32bit - 32bit
+ - expand right data block
+ - xor right block with subkey i (or 15-i)
+ - do sbox and pbox permutations
+ - xor result with left data block
+ - switch left and right data block (not for last cycle)
+ - loop 16 times
+ - do final permutation
+ */
+ for(i=0;i<len/8;i++) {
+ if((mode&MODE_CBC)&&(mode&MODE_CRYPT)&&(i!=0))
+ for(j=0;j<8;j++) src[i*8+j]^=final[(i-1)*8+j];
+ progress_data(src+i*8,final+i*8,subkey,mode);
+ if((mode&MODE_CBC)&&(mode&MODE_DECRYPT)&&(i!=0))
+ for(j=0;j<8;j++) final[(i*8)+j]^=src[(i-1)*8+j];
+ }
+ return 1;
+}
+int des_encrypt(u8 *plain,u8 *crypted,u8 *key,int len,u8 mode) {
+ des_crypt_decrypt(plain,crypted,key,len,MODE_CRYPT|mode);
+ return 1;
+}
+int des_decrypt(u8 *crypted,u8 *plain,u8 *key,int len,u8 mode) {
+ des_crypt_decrypt(crypted,plain,key,len,MODE_DECRYPT|mode);
return 1;
}
projects / my-code / crypto.git / blobdiff