view libtomcrypt/notes/etc/saferp_optimizer.c @ 1902:4a6725ac957c

Revert "Don't include sk keys at all in KEX list" This reverts git commit f972813ecdc7bb981d25b5a63638bd158f1c8e72. The sk algorithms need to remain in the sigalgs list so that they are included in the server-sig-algs ext-info message sent by the server. RFC8308 for server-sig-algs requires that all algorithms are listed (though OpenSSH client 8.4p1 tested doesn't require that)
author Matt Johnston <matt@ucc.asn.au>
date Thu, 24 Mar 2022 13:42:08 +0800
parents 6dba84798cd5
children
line wrap: on
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/* emits an optimized version of LTC_SAFER+ ... only does encrypt so far... */

#include <stdio.h>
#include <string.h>

/* This is the "Armenian" Shuffle.  It takes the input from b and stores it in b2 */
#define SHUF\
    b2[0] = b[8]; b2[1] = b[11]; b2[2] = b[12]; b2[3] = b[15];   \
    b2[4] = b[2]; b2[5] = b[1]; b2[6] = b[6]; b2[7] = b[5];      \
    b2[8] = b[10]; b2[9] = b[9]; b2[10] = b[14]; b2[11] = b[13]; \
    b2[12] = b[0]; b2[13] = b[7]; b2[14] = b[4]; b2[15] = b[3]; memcpy(b, b2, sizeof(b));

/* This is the inverse shuffle.  It takes from b and gives to b2 */
#define iSHUF(b, b2)                                               \
    b2[0] = b[12]; b2[1] = b[5]; b2[2] = b[4]; b2[3] = b[15];      \
    b2[4] = b[14]; b2[5] = b[7]; b2[6] = b[6]; b2[7] = b[13];      \
    b2[8] = b[0]; b2[9] = b[9]; b2[10] = b[8]; b2[11] = b[1];      \
    b2[12] = b[2]; b2[13] = b[11]; b2[14] = b[10]; b2[15] = b[3]; memcpy(b, b2, sizeof(b));
    
#define ROUND(b, i)                                                                        \
    b[0]  = (safer_ebox[(b[0] ^ skey->saferp.K[i][0]) & 255] + skey->saferp.K[i+1][0]) & 255;    \
    b[1]  = safer_lbox[(b[1] + skey->saferp.K[i][1]) & 255] ^ skey->saferp.K[i+1][1];            \
    b[2]  = safer_lbox[(b[2] + skey->saferp.K[i][2]) & 255] ^ skey->saferp.K[i+1][2];            \
    b[3]  = (safer_ebox[(b[3] ^ skey->saferp.K[i][3]) & 255] + skey->saferp.K[i+1][3]) & 255;    \
    b[4]  = (safer_ebox[(b[4] ^ skey->saferp.K[i][4]) & 255] + skey->saferp.K[i+1][4]) & 255;    \
    b[5]  = safer_lbox[(b[5] + skey->saferp.K[i][5]) & 255] ^ skey->saferp.K[i+1][5];            \
    b[6]  = safer_lbox[(b[6] + skey->saferp.K[i][6]) & 255] ^ skey->saferp.K[i+1][6];            \
    b[7]  = (safer_ebox[(b[7] ^ skey->saferp.K[i][7]) & 255] + skey->saferp.K[i+1][7]) & 255;    \
    b[8]  = (safer_ebox[(b[8] ^ skey->saferp.K[i][8]) & 255] + skey->saferp.K[i+1][8]) & 255;    \
    b[9]  = safer_lbox[(b[9] + skey->saferp.K[i][9]) & 255] ^ skey->saferp.K[i+1][9];            \
    b[10] = safer_lbox[(b[10] + skey->saferp.K[i][10]) & 255] ^ skey->saferp.K[i+1][10];         \
    b[11] = (safer_ebox[(b[11] ^ skey->saferp.K[i][11]) & 255] + skey->saferp.K[i+1][11]) & 255; \
    b[12] = (safer_ebox[(b[12] ^ skey->saferp.K[i][12]) & 255] + skey->saferp.K[i+1][12]) & 255; \
    b[13] = safer_lbox[(b[13] + skey->saferp.K[i][13]) & 255] ^ skey->saferp.K[i+1][13];         \
    b[14] = safer_lbox[(b[14] + skey->saferp.K[i][14]) & 255] ^ skey->saferp.K[i+1][14];         \
    b[15] = (safer_ebox[(b[15] ^ skey->saferp.K[i][15]) & 255] + skey->saferp.K[i+1][15]) & 255;        

int main(void)
{
   int b[16], b2[16], x, y, z;
   
/* -- ENCRYPT ---  */
   for (x = 0; x < 16; x++) b[x] = x;
   /* emit encrypt preabmle  */
printf(
"void saferp_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey)\n"
"{\n"
"   int x;\n"
"   unsigned char b[16];\n"
"\n"
"   LTC_ARGCHK(pt   != NULL);\n"
"   LTC_ARGCHK(ct   != NULL);\n"
"   LTC_ARGCHK(skey != NULL);\n"
"\n"
"   /* do eight rounds */\n"
"   for (x = 0; x < 16; x++) {\n"
"       b[x] = pt[x];\n"
"   }\n");   

   /* do 8 rounds of ROUND; LT; */
   for (x = 0; x < 8; x++) {
       /* ROUND(..., x*2) */
       for (y = 0; y < 16; y++) {
printf("b[%d] = (safer_%cbox[(b[%d] %c skey->saferp.K[%d][%d]) & 255] %c skey->saferp.K[%d][%d]) & 255;\n",
          b[y], "elle"[y&3], b[y], "^++^"[y&3],      x*2, y, "+^^+"[y&3], x*2+1, y);
       }
       
       /* LT */
       for (y = 0; y < 4; y++) {
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[0], b[0], b[1], b[0], b[1]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[2], b[2], b[3], b[3], b[2]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[4], b[4], b[5], b[5], b[4]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[6], b[6], b[7], b[7], b[6]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[8], b[8], b[9], b[9], b[8]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[10], b[10], b[11], b[11], b[10]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[12], b[12], b[13], b[13], b[12]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[14], b[14], b[15], b[15], b[14]);
      if (y < 3) {
         SHUF;
      }         
      }   
  }
  
printf(
"   if (skey->saferp.rounds <= 8) {\n");
/* finish */
   for (x = 0; x < 16; x++) {
   printf(
"      ct[%d] = (b[%d] %c skey->saferp.K[skey->saferp.rounds*2][%d]) & 255;\n",
       x, b[x], "^++^"[x&3], x);
   }   
   printf("      return;\n   }\n");
  
  /* 192-bit keys */
printf(  
"   /* 192-bit key? */\n"
"   if (skey->saferp.rounds > 8) {\n");
  
   /* do 4 rounds of ROUND; LT; */
   for (x = 8; x < 12; x++) {
       /* ROUND(..., x*2) */
       for (y = 0; y < 16; y++) {
printf("b[%d] = (safer_%cbox[(b[%d] %c skey->saferp.K[%d][%d]) & 255] %c skey->saferp.K[%d][%d]) & 255;\n",
          b[y], "elle"[y&3], b[y], "^++^"[y&3],      x*2, y, "+^^+"[y&3], x*2+1, y);
       }
       
       /* LT */
       for (y = 0; y < 4; y++) {
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[0], b[0], b[1], b[0], b[1]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[2], b[2], b[3], b[3], b[2]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[4], b[4], b[5], b[5], b[4]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[6], b[6], b[7], b[7], b[6]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[8], b[8], b[9], b[9], b[8]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[10], b[10], b[11], b[11], b[10]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[12], b[12], b[13], b[13], b[12]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[14], b[14], b[15], b[15], b[14]);
      if (y < 3) {
         SHUF;
      }         
      }   
  }
printf("}\n");
  
printf(
"   if (skey->saferp.rounds <= 12) {\n");
/* finish */
   for (x = 0; x < 16; x++) {
   printf(
"      ct[%d] = (b[%d] %c skey->saferp.K[skey->saferp.rounds*2][%d]) & 255;\n",
       x, b[x], "^++^"[x&3], x);
   }   
   printf("      return;\n   }\n");

  /* 256-bit keys */
printf(  
"   /* 256-bit key? */\n"
"   if (skey->saferp.rounds > 12) {\n");
  
   /* do 4 rounds of ROUND; LT; */
   for (x = 12; x < 16; x++) {
       /* ROUND(..., x*2) */
       for (y = 0; y < 16; y++) {
printf("b[%d] = (safer_%cbox[(b[%d] %c skey->saferp.K[%d][%d]) & 255] %c skey->saferp.K[%d][%d]) & 255;\n",
          b[y], "elle"[y&3], b[y], "^++^"[y&3],      x*2, y, "+^^+"[y&3], x*2+1, y);
       }
       
       /* LT */
       for (y = 0; y < 4; y++) {
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[0], b[0], b[1], b[0], b[1]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[2], b[2], b[3], b[3], b[2]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[4], b[4], b[5], b[5], b[4]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[6], b[6], b[7], b[7], b[6]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[8], b[8], b[9], b[9], b[8]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[10], b[10], b[11], b[11], b[10]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[12], b[12], b[13], b[13], b[12]);
printf("   b[%d]  = (b[%d] + (b[%d] = (b[%d] + b[%d]) & 255)) & 255;\n", b[14], b[14], b[15], b[15], b[14]);
      if (y < 3) {
         SHUF;
      }         
      }   
  }
/* finish */
   for (x = 0; x < 16; x++) {
   printf(
"      ct[%d] = (b[%d] %c skey->saferp.K[skey->saferp.rounds*2][%d]) & 255;\n",
       x, b[x], "^++^"[x&3], x);
   }   
   printf("   return;\n");
printf("   }\n}\n\n");

   return 0;
}


/* ref:         $Format:%D$ */
/* git commit:  $Format:%H$ */
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