File indexing completed on 2024-05-12 05:46:50

 /*
  * Software DES functions
  *
  * Copyright 1988-1991 Phil Karn <karn@ka9q.net>
  * Copyright 2003      Nikos Mavroyanopoulos <nmav@hellug.gr>
  *
  * Taken from libmcrypt (http://mcrypt.hellug.gr/lib/index.html).
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  * MA  02110-1301  USA
  */
 
 /* Software DES functions
  * written 12 Dec 1986 by Phil Karn, KA9Q; large sections adapted from
  * the 1977 public-domain program by Jim Gillogly
  * Modified for additional speed - 6 December 1988 Phil Karn
  * Modified for parameterized key schedules - Jan 1991 Phil Karn
  * Callers now allocate a key schedule as follows:
  *  kn = (char (*)[8])malloc(sizeof(char) * 8 * 16);
  *  or
  *  char kn[16][8];
  */
 
 /* modified in order to use the libmcrypt API by Nikos Mavroyanopoulos
  * All modifications are placed under the license of libmcrypt.
  */
 
 #include "des.h"
 
 #include <string.h>
 #include <qendian.h>
 
 static void permute_ip(unsigned char *inblock, DES_KEY *key, unsigned char *outblock);
 static void permute_fp(unsigned char *inblock, DES_KEY *key, unsigned char *outblock);
 static void perminit_ip(DES_KEY *key);
 static void spinit(DES_KEY *key);
 static void perminit_fp(DES_KEY *key);
 static quint32 f(DES_KEY *key,  quint32 r,  char *subkey);
 
 /* Tables defined in the Data Encryption Standard documents */
 
 /* initial permutation IP */
 static const char ip[] = {
     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
 };
 
 /* final permutation IP^-1 */
 static const char fp[] = {
     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
 };
 
 /* expansion operation matrix
  * This is for reference only; it is unused in the code
  * as the f() function performs it implicitly for speed
  */
 #ifdef notdef
 static const char ei[] = {
     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
 };
 #endif
 
 /* permuted choice table (key) */
 static const char pc1[] = {
     57, 49, 41, 33, 25, 17, 9,
     1, 58, 50, 42, 34, 26, 18,
     10, 2, 59, 51, 43, 35, 27,
     19, 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
 };
 
 /* number left rotations of pc1 */
 static const char totrot[] = {
     1, 2, 4, 6, 8, 10, 12, 14, 15, 17, 19, 21, 23, 25, 27, 28
 };
 
 /* permuted choice key (table) */
 static const char pc2[] = {
     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
 };
 
 /* The (in)famous S-boxes */
 static const char si[8][64] = {
     /* S1 */
     {
         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
     },
 
     /* S2 */
     {
         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
     },
 
     /* S3 */
     {
         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
     },
 
     /* S4 */
     {
         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
     },
 
     /* S5 */
     {
         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
     },
 
     /* S6 */
     {
         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
     },
 
     /* S7 */
     {
         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
     },
 
     /* S8 */
     {
         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
     },
 
 };
 
 /* 32-bit permutation function P used on the output of the S-boxes */
 static const char p32i[] = {
     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
 };
 
 /* End of DES-defined tables */
 
 /* Lookup tables initialized once only at startup by desinit() */
 
 /* bit 0 is left-most in byte */
 static const int bytebit[] = {
     0200, 0100, 040, 020, 010, 04, 02, 01
 };
 
 static const int nibblebit[] = {
     010, 04, 02, 01
 };
 
 /* Allocate space and initialize DES lookup arrays
  * mode == 0: standard Data Encryption Algorithm
  */
 static int
 desinit(DES_KEY *key)
 {
 
     spinit(key);
     perminit_ip(key);
     perminit_fp(key);
 
     return 0;
 }
 
 /* Set key (initialize key schedule array) */
 int
 ntlm_des_set_key(DES_KEY *dkey, char *user_key, int /*len*/)
 {
     char pc1m[56];        /* place to modify pc1 into */
     char pcr[56];         /* place to rotate pc1 into */
     int i, j, l;
     int m;
 
     memset(dkey, 0, sizeof(DES_KEY));
     desinit(dkey);
 
     /* Clear key schedule */
 
     for (j = 0; j < 56; ++j) {
         /* convert pc1 to bits of key */
         l = pc1[j] - 1;       /* integer bit location  */
         m = l & 07;       /* find bit              */
         pc1m[j] = (user_key[l >> 3] & /* find which key byte l is in */
                    bytebit[m])    /* and which bit of that byte */
                   ? 1 : 0;        /* and store 1-bit result */
 
     }
     for (i = 0; i < 16; ++i) {
         /* key chunk for each iteration */
         for (j = 0; j < 56; ++j) { /* rotate pc1 the right amount */
             pcr[j] = pc1m[(l = j + totrot[i]) < (j < 28 ? 28 : 56) ? l : l - 28];
         }
         /* rotate left and right halves independently */
         for (j = 0; j < 48; ++j) {
             /* select bits individually */
             /* check bit that goes to kn[j] */
             if (pcr[pc2[j] - 1]) {
                 /* mask it in if it's there */
                 l = j % 6;
                 dkey->kn[i][j / 6] |= bytebit[l] >> 2;
             }
         }
     }
     return 0;
 }
 
 /* In-place encryption of 64-bit block */
 static void
 ntlm_des_encrypt(DES_KEY *key, unsigned char *block)
 {
     quint32 left, right;
     char *knp;
     quint32 work[2];      /* Working data storage */
 
     permute_ip(block, key, (unsigned char *) work);   /* Initial Permutation */
     left = qFromBigEndian(work[0]);
     right = qFromBigEndian(work[1]);
 
     /* Do the 16 rounds.
      * The rounds are numbered from 0 to 15. On even rounds
      * the right half is fed to f() and the result exclusive-ORs
      * the left half; on odd rounds the reverse is done.
      */
     knp = &key->kn[0][0];
     left ^= f(key, right, knp);
     knp += 8;
     right ^= f(key, left, knp);
     knp += 8;
     left ^= f(key, right, knp);
     knp += 8;
     right ^= f(key, left, knp);
     knp += 8;
     left ^= f(key, right, knp);
     knp += 8;
     right ^= f(key, left, knp);
     knp += 8;
     left ^= f(key, right, knp);
     knp += 8;
     right ^= f(key, left, knp);
     knp += 8;
     left ^= f(key, right, knp);
     knp += 8;
     right ^= f(key, left, knp);
     knp += 8;
     left ^= f(key, right, knp);
     knp += 8;
     right ^= f(key, left, knp);
     knp += 8;
     left ^= f(key, right, knp);
     knp += 8;
     right ^= f(key, left, knp);
     knp += 8;
     left ^= f(key, right, knp);
     knp += 8;
     right ^= f(key, left, knp);
 
     /* Left/right half swap, plus byte swap if little-endian */
     work[1] = qToBigEndian(left);
     work[0] = qToBigEndian(right);
 
     permute_fp((unsigned char *) work, key, block);   /* Inverse initial permutation */
 }
 
 /* Permute inblock with perm */
 static void
 permute_ip(unsigned char *inblock, DES_KEY *key, unsigned char *outblock)
 {
     unsigned char *ib, *ob;  /* ptr to input or output block */
     char *p, *q;
     int j;
 
     /* Clear output block */
     memset(outblock, 0, 8);
 
     ib = inblock;
     for (j = 0; j < 16; j += 2, ++ib) {
         /* for each input nibble */
         ob = outblock;
         p = key->iperm[j][(*ib >> 4) & 0xf];
         q = key->iperm[j + 1][*ib & 0xf];
         /* and each output byte, OR the masks together */
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
     }
 }
 
 /* Permute inblock with perm */
 static void
 permute_fp(unsigned char *inblock, DES_KEY *key, unsigned char *outblock)
 {
     unsigned char *ib, *ob;  /* ptr to input or output block */
     char *p, *q;
     int j;
 
     /* Clear output block */
     memset(outblock, 0, 8);
 
     ib = inblock;
     for (j = 0; j < 16; j += 2, ++ib) {
         /* for each input nibble */
         ob = outblock;
         p = key->fperm[j][(*ib >> 4) & 0xf];
         q = key->fperm[j + 1][*ib & 0xf];
         /* and each output byte, OR the masks together */
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
         *ob++ |= *p++ | *q++;
     }
 }
 
 /* The nonlinear function f(r,k), the heart of DES */
 static quint32
 f(DES_KEY *key,  quint32 r,  char *subkey)
 {
     quint32 *spp;
     quint32 rval, rt;
     int er;
 
 #ifdef  TRACE
     printf("f(%08lx, %02x %02x %02x %02x %02x %02x %02x %02x) = ",
            r,
            subkey[0], subkey[1], subkey[2],
            subkey[3], subkey[4], subkey[5], subkey[6], subkey[7]);
 #endif
     /* Run E(R) ^ K through the combined S & P boxes.
      * This code takes advantage of a convenient regularity in
      * E, namely that each group of 6 bits in E(R) feeding
      * a single S-box is a contiguous segment of R.
      */
     subkey += 7;
 
     /* Compute E(R) for each block of 6 bits, and run thru boxes */
     er = ((int) r << 1) | ((r & 0x80000000) ? 1 : 0);
     spp = &key->sp[7][0];
     rval = spp[(er ^ *subkey--) & 0x3f];
     spp -= 64;
     rt = (quint32) r >> 3;
     rval |= spp[((int) rt ^ *subkey--) & 0x3f];
     spp -= 64;
     rt >>= 4;
     rval |= spp[((int) rt ^ *subkey--) & 0x3f];
     spp -= 64;
     rt >>= 4;
     rval |= spp[((int) rt ^ *subkey--) & 0x3f];
     spp -= 64;
     rt >>= 4;
     rval |= spp[((int) rt ^ *subkey--) & 0x3f];
     spp -= 64;
     rt >>= 4;
     rval |= spp[((int) rt ^ *subkey--) & 0x3f];
     spp -= 64;
     rt >>= 4;
     rval |= spp[((int) rt ^ *subkey--) & 0x3f];
     spp -= 64;
     rt >>= 4;
     rt |= (r & 1) << 5;
     rval |= spp[((int) rt ^ *subkey) & 0x3f];
 #ifdef  TRACE
     printf(" %08lx\n", rval);
 #endif
     return rval;
 }
 
 /* initialize a perm array */
 static void
 perminit_ip(DES_KEY *key)
 {
     int l, j, k;
     int i, m;
 
     /* Clear the permutation array */
     memset(key->iperm, 0, 16 * 16 * 8);
 
     for (i = 0; i < 16; ++i)  /* each input nibble position */
         for (j = 0; j < 16; ++j)    /* each possible input nibble */
             for (k = 0; k < 64; ++k) {
                 /* each output bit position */
                 l = ip[k] - 1;    /* where does this bit come from */
                 if ((l >> 2) != i) {  /* does it come from input posn? */
                     continue;    /* if not, bit k is 0    */
                 }
                 if (!(j & nibblebit[l & 3])) {
                     continue;    /* any such bit in input? */
                 }
                 m = k & 07;       /* which bit is this in the byte */
                 key->iperm[i][j][k >> 3] |= bytebit[m];
             }
 }
 
 static void
 perminit_fp(DES_KEY *key)
 {
     int l, j, k;
     int i, m;
 
     /* Clear the permutation array */
     memset(key->fperm, 0, 16 * 16 * 8);
 
     for (i = 0; i < 16; ++i)  /* each input nibble position */
         for (j = 0; j < 16; ++j)    /* each possible input nibble */
             for (k = 0; k < 64; ++k) {
                 /* each output bit position */
                 l = fp[k] - 1;    /* where does this bit come from */
                 if ((l >> 2) != i) {  /* does it come from input posn? */
                     continue;    /* if not, bit k is 0    */
                 }
                 if (!(j & nibblebit[l & 3])) {
                     continue;    /* any such bit in input? */
                 }
                 m = k & 07;       /* which bit is this in the byte */
                 key->fperm[i][j][k >> 3] |= bytebit[m];
             }
 }
 
 /* Initialize the lookup table for the combined S and P boxes */
 static void
 spinit(DES_KEY *key)
 {
     char pbox[32];
     int p, i, s, j, rowcol;
     quint32 val;
 
     /* Compute pbox, the inverse of p32i.
      * This is easier to work with
      */
     for (p = 0; p < 32; ++p) {
         for (i = 0; i < 32; ++i) {
             if (p32i[i] - 1 == p) {
                 pbox[p] = i;
                 break;
             }
         }
     }
     for (s = 0; s < 8; ++s) {
         /* For each S-box */
         for (i = 0; i < 64; ++i) {
             /* For each possible input */
             val = 0;
             /* The row number is formed from the first and last
              * bits; the column number is from the middle 4
              */
             rowcol = (i & 32) | ((i & 1) ? 16 : 0) | ((i >> 1) & 0xf);
             for (j = 0; j < 4; j++) {
                 /* For each output bit */
                 if (si[s][rowcol] & (8 >> j)) {
                     val |= 1L << (31 - pbox[4 * s + j]);
                 }
             }
             key->sp[s][i] = val;
         }
     }
 }
 
 int
 ntlm_des_ecb_encrypt(const void *plaintext, int len, DES_KEY *akey,
                      unsigned char output[8])
 {
     int j;
     const unsigned char *plain = (const unsigned char *) plaintext;
 
     for (j = 0; j < len / 8; ++j) {
         memcpy(&output[j * 8], &plain[j * 8], 8);
         ntlm_des_encrypt(akey, &output[j * 8]);
     }
 
     if (j == 0 && len != 0) {
         return -1;    /* no blocks were encrypted */
     }
     return 0;
 }