From ac304c536726578d9276356343594dc015c34415 Mon Sep 17 00:00:00 2001 From: hackbard Date: Wed, 1 Oct 2003 09:20:13 +0000 Subject: [PATCH] - --- des.c | 183 +++++++++++++++++++++++++++++++++++++++++++++++++++------- des.h | 19 ++++-- 2 files changed, 175 insertions(+), 27 deletions(-) diff --git a/des.c b/des.c index db0aba8..4c0a358 100644 --- a/des.c +++ b/des.c @@ -14,17 +14,71 @@ u8 key_perm_table[DES_SUBKEY_LEN]={ 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 }; +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 +}; + int rotate_right(u8 *obj,int len) { u8 tmp=obj[len-1]; while(--len) obj[len]=obj[len]>>1|((obj[len-1]&1)<<7); @@ -42,48 +96,133 @@ int rotate_left(u8 *obj,int len) { key_perm(u8 *key) { int i; - u8 *new[DES_SUBKEY_LEN/8]; - memset(new,0,DES_SUBKEY_LEN/8]; - for(i=0;i>((8-key_perm_table[i]%8)&7))&1)<<(7-i%8)); - memcpy(key,new,DES_SUBKEY_LEN); + u8 new[DES_INITIAL_KEY_LEN/8]; + memset(new,0,DES_INITIAL_KEY_LEN/8]; + for(i=0;i>((8-key_perm_table[i]%8)&7))&1)<<(7-i%8)); + memcpy(key,new,DES_INITIAL_KEY_LEN); return 1; } int subkey_trans(u8 *key,int round) { int i; for(i=0;i>((8-subkey_perm_table[i]%8)&7)&1))<<(7-i%8)); + memset(pc,0,DES_SUBKEY_LEN/8); + for(i=0;i>((8-subkey_perm_table[i]%8)&7))&1)<<(7-i%8)); + return 1; +} - +int compute_subkeys(u8 *key0,u8 **subkey) { + int i; + key_perm(key0); + for(i=0;i>((8-data_perm_table[i]%8)&7))&1)<<(7-i%8)); + return 1; +} + +int data_expansion_perm(u8 *right,u8 expanded) { + int i; + memset(expanded,0,DES_SUBKEY_LEN); + for(i=0;i>((8-data_expansion_table[i]%8)&7))&1)<<(7-i%8)); + return 1; +} + +int get_sbox_value(u8 *data,int offset,int len,int box) { + int tmp; + tmp=((offset%8)==0)?data[offset/8]>>(8-len):((data[offset/8]&((1<<(offset%8))-1))<<(offset%8))|(data[(offset/8)+1]>>(len-(8-(offset%8)))); + return(sbox[box][(tmp&1|(tmp&(1<<(len-1))<<1))*16+(tmp&((1<<(len-1))-1)>>1)]); +} + +int data_s_and_p(u8 *data) { + u8 s[DES_DATA_BLOCK_LEN/2]; + u8 p[DES_DATA_BLOCK_LEN/2]; + int i,j; + for(i=0;i 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 all data do: (not yet ready) */ + progress_data(plain,subkey,mode); return 1; } -int des_decrypt(u8 *crypted,u8 *plain,u8 *key) { +int des_crypt(u8 *plain,u8 *crypted,u8 *key,int len,MODE_CRYPT) { + + return 1; +} +int des_decrypt(u8 *crypted,u8 *plain,u8 *key,int len,MODE_DECRYPT) { return 1; } diff --git a/des.h b/des.h index ed1750c..12da455 100644 --- a/des.h +++ b/des.h @@ -8,13 +8,22 @@ #ifndef DES_H #define DES_H -#define DES_ROUNDS 16 -#define DES_SUBKEY_LEN 56 -#define DES_PERMC_LEN 48 +#define DES_SUBKEYS 16 +#define DES_INITIAL_KEY_LEN 56 +#define DES_SUBKEY_LEN 48 +#define DES_DATA_BLOCK_LEN 64 +#define DES_SBOXES 8 +#define DES_SBOX_LEN 64 +#define DES_PBOX_LEN 32 + +#define MODE_CRYPT 1 +#define MODE_DECRYPT 2 +#define MODE_ECB 4 +#define MODE_CBC 8 typedef unsigned char u8; -int des_encrypt(u8 *plain,u8 *crypted,u8 *key); -int des_decrypt(u8 *crypted,u8 *plain,u8 *key); +int des_encrypt(u8 *plain,u8 *crypted,u8 *key,int len,u8 mode); +int des_decrypt(u8 *crypted,u8 *plain,u8 *key,int len,u8 mode); #endif /* DES_H */ -- 2.39.2