X-Git-Url: https://hackdaworld.org/gitweb/?p=my-code%2Fcrypto.git;a=blobdiff_plain;f=des.c;h=a001060759c6023d40c734fe23cc92fa95d5b7b1;hp=722e1cc790443797137eab823fd245fd3519cb90;hb=HEAD;hpb=813819fc21f3a9ebada1f6b4caef59be10ea07dc

diff --git a/des.c b/des.c
index 722e1cc..a001060 100644
--- a/des.c
+++ b/des.c
@@ -87,18 +87,29 @@ u8 data_final_perm_table[DES_DATA_BLOCK_LEN]={
  34,2,42,10,50,18,58,26,33,1,41,9,49,17,57,25
 };
 
-int rotate_right(u8 *obj,int len) {
- u8 tmp=obj[len-1];
- while(--len) obj[len]=obj[len]>>1|((obj[len-1]&1)<<7);
- obj[0]=obj[0]>>1|((tmp&1)<<7);;
+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[i+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;
 }
 
@@ -106,16 +117,14 @@ int table_trans(u8 *src,u8 *final,u8 *table,int len) {
  int i;
  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;
+  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_INITIAL_KEY_LEN/(8*2));
-  rotate_left(key+DES_INITIAL_KEY_LEN/(8*2),DES_INITIAL_KEY_LEN/(8*2));
- }
+ for(i=0;i<rot_per_round_table[round];i++)
+  rotate_left(key);
  return 1;
 }
 
@@ -133,17 +142,17 @@ int compute_subkeys(u8 *key0,u8 subkey[DES_SUBKEYS][DES_SUBKEY_LEN/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/(8*2)];
- int i;
- for(i=0;i<DES_SBOXES;i++)
-  s[i]=get_sbox_value(data,i*(DES_SUBKEY_LEN/DES_SBOXES),(DES_SUBKEY_LEN/DES_SBOXES),i);
+ 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;
 }
@@ -167,11 +176,15 @@ int progress_data(u8 *data,u8 *crypted,u8 subkey[DES_SUBKEYS][DES_SUBKEY_LEN/8],
   /* sbox substitutions and pbox permutations */
   data_s_and_p(permuted_data);
   /* xor with left data */
-  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 */
-  if(i!=15) memcpy(left,tmp,DES_DATA_BLOCK_LEN/(2*8)); 
+  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));