The Tor Browser: security/nss/lib/freebl/mknewpc2.c@b8a032363ba2 (annotated)

security/nss/lib/freebl/mknewpc2.c@b8a032363ba2 (annotated)

security/nss/lib/freebl/mknewpc2.c

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /*
  *  mknewpc2.c
  *
  *  Generate PC-2 tables for DES-150 library
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 typedef unsigned char BYTE;
 typedef unsigned int  HALF;
 #define DES_ENCRYPT 0
 #define DES_DECRYPT 1
 /* two 28-bit registers defined in key schedule production process */
 static HALF C0, D0;
 static HALF L0, R0;
 /* key schedule, 16 internal keys, each with 8 6-bit parts */
 static BYTE KS [8] [16];
 /*
  * This table takes the 56 bits in C0 and D0 and shows show they are
  * permuted into the 8 6-bit parts of the key in the key schedule.
  * The bits of C0 are numbered left to right, 1-28.
  * The bits of D0 are numbered left to right, 29-56.
  * Zeros in this table represent bits that are always zero.
  * Note that all the bits in the first  4 rows come from C0,
  *       and all the bits in the second 4 rows come from D0.
  */
 static const BYTE PC2[64] = {
 , 17, 11, 24,  1,  5,  0,  0,	/* S1 */
 , 28, 15,  6, 21, 10,  0,  0,	/* S2 */
 , 19, 12,  4, 26,  8,  0,  0,	/* S3 */
 ,  7, 27, 20, 13,  2,  0,  0,	/* S4 */
 , 52, 31, 37, 47, 55,  0,  0,	/* S5 */
 , 40, 51, 45, 33, 48,  0,  0,	/* S6 */
 , 49, 39, 56, 34, 53,  0,  0,	/* S7 */
 , 42, 50, 36, 29, 32,  0,  0	/* S8 */
 };
 /* This table represents the same info as PC2, except that
  * The bits of C0 and D0 are each numbered right to left, 0-27.
  * -1 values indicate bits that are always zero.
  * As before all the bits in the first  4 rows come from C0,
  *       and all the bits in the second 4 rows come from D0.
  */
 static       signed char PC2a[64] = {
 /* bits of C0 */
 , 11, 17,  4, 27, 23, -1, -1,	/* S1 */
 ,  0, 13, 22,  7, 18, -1, -1,	/* S2 */
 ,  9, 16, 24,  2, 20, -1, -1,	/* S3 */
 , 21,  1,  8, 15, 26, -1, -1,	/* S4 */
 /* bits of D0 */
 ,  4, 25, 19,  9,  1, -1, -1,	/* S5 */
 , 16,  5, 11, 23,  8, -1, -1,	/* S6 */
 ,  7, 17,  0, 22,  3, -1, -1,	/* S7 */
 , 14,  6, 20, 27, 24, -1, -1 	/* S8 */
 };
 /* This table represents the same info as PC2a, except that
  * The order of of the rows has been changed to increase the efficiency
  * with which the key sechedule is created.
  * Fewer shifts and ANDs are required to make the KS from these.
  */
 static const signed char PC2b[64] = {
 /* bits of C0 */
 , 11, 17,  4, 27, 23, -1, -1,	/* S1 */
 ,  9, 16, 24,  2, 20, -1, -1,	/* S3 */
 ,  0, 13, 22,  7, 18, -1, -1,	/* S2 */
 , 21,  1,  8, 15, 26, -1, -1,	/* S4 */
 /* bits of D0 */
 , 16,  5, 11, 23,  8, -1, -1,	/* S6 */
 , 14,  6, 20, 27, 24, -1, -1,	/* S8 */
 ,  4, 25, 19,  9,  1, -1, -1,	/* S5 */
 ,  7, 17,  0, 22,  3, -1, -1 	/* S7 */
 };
 /* Only 24 of the 28 bits in C0 and D0 are used in PC2.
  * The used bits of C0 and D0 are grouped into 4 groups of 6,
  * so that the PC2 permutation can be accomplished with 4 lookups
  * in tables of 64 entries.
  * The following table shows how the bits of C0 and D0 are grouped
  * into indexes for the respective table lookups.
  * Bits are numbered right-to-left, 0-27, as in PC2b.
  */
 static BYTE NDX[48] = {
 /* Bits of C0 */
 , 26, 25, 24, 23, 22,	/* C0 table 0 */
 , 17, 16, 15, 14, 13,	/* C0 table 1 */
 ,  8,  7,  2,  1,  0,	/* C0 table 2 */
 ,  4, 21, 20, 12, 11,	/* C0 table 3 */
 /* bits of D0 */
 , 26, 25, 24, 23, 22,	/* D0 table 0 */
 , 19, 17, 16, 15, 14,	/* D0 table 1 */
 , 11, 10,  9,  8,  7,	/* D0 table 2 */
 ,  5,  4,  3,  1,  0	/* D0 table 3 */
 };
 /* Here's the code that does that grouping.
 	left   = PC2LOOKUP(0, 0, ((c0 >> 22) & 0x3F) );
 	left  |= PC2LOOKUP(0, 1, ((c0 >> 13) & 0x3F) );
 	left  |= PC2LOOKUP(0, 2, ((c0 >>  4) & 0x38) | (c0 & 0x7) );
 	left  |= PC2LOOKUP(0, 3, ((c0>>18)&0xC) | ((c0>>11)&0x3) | (c0&0x30));
 	right  = PC2LOOKUP(1, 0, ((d0 >> 22) & 0x3F) );
 	right |= PC2LOOKUP(1, 1, ((d0 >> 15) & 0x30) | ((d0 >> 14) & 0xf) );
 	right |= PC2LOOKUP(1, 2, ((d0 >>  7) & 0x3F) );
 	right |= PC2LOOKUP(1, 3, ((d0 >>  1) & 0x3C) | (d0 & 0x3));
 */
 void
 make_pc2a( void )
 {
     int i, j;
     for ( i = 0; i < 64; ++i ) {
 	j = PC2[i];
 	if (j == 0)
 	    j = -1;
 	else if ( j < 29 )
 	    j = 28 - j ;
 	else
 	    j = 56 - j;
 	PC2a[i] = j;
     }
     for ( i = 0; i < 64; i += 8 ) {
 	printf("%3d,%3d,%3d,%3d,%3d,%3d,%3d,%3d,\n",
 		PC2a[i+0],PC2a[i+1],PC2a[i+2],PC2a[i+3],
 		PC2a[i+4],PC2a[i+5],PC2a[i+6],PC2a[i+7] );
     }
 }
 HALF PC2cd0[64];
 HALF PC_2H[8][64];
 void
 mktable( )
 {
     int i;
     int table;
     const BYTE * ndx   = NDX;
     HALF         mask;
     mask  = 0x80000000;
     for (i = 0; i < 32; ++i, mask >>= 1) {
 	int bit = PC2b[i];
 	if (bit < 0)
 	    continue;
 	PC2cd0[bit + 32] = mask;
     }
     mask  = 0x80000000;
     for (i = 32; i < 64; ++i, mask >>= 1) {
 	int bit = PC2b[i];
 	if (bit < 0)
 	    continue;
 	PC2cd0[bit] = mask;
     }
 #if DEBUG
     for (i = 0; i < 64; ++i) {
     	printf("0x%08x,\n", PC2cd0[i]);
     }
 #endif
     for (i = 0; i < 24; ++i) {
     	NDX[i] += 32;	/* because c0 is the upper half */
     }
     for (table = 0; table < 8; ++table) {
 	HALF bitvals[6];
     	for (i = 0; i < 6; ++i) {
 	    bitvals[5-i] = PC2cd0[*ndx++];
 	}
 	for (i = 0; i < 64; ++i) {
 	    int  j;
 	    int  k     = 0;
 	    HALF value = 0;
 	    for (j = i; j; j >>= 1, ++k) {
 	    	if (j & 1) {
 		    value |= bitvals[k];
 		}
 	    }
 	    PC_2H[table][i] = value;
 	}
 	printf("/* table %d */ {\n", table );
 	for (i = 0; i < 64; i += 4) {
 	    printf("    0x%08x, 0x%08x, 0x%08x, 0x%08x, \n",
 		    PC_2H[table][i],   PC_2H[table][i+1],
 		    PC_2H[table][i+2], PC_2H[table][i+3]);
 	}
 	printf("  },\n");
     }
 }
 int
 main(void)
 {
 /*   make_pc2a(); */
    mktable();
    return 0;
 }

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security/nss/lib/freebl/mknewpc2.c@b8a032363ba2 (annotated)

security/nss/lib/freebl/mknewpc2.c