/*++ Copyright (c) 1987-1994 Microsoft Corporation Module Name: arapdes.c Abstract: This module implements the ARAP-specific authentication that is called in by the subauthentication package if the protocol type is ARAP. This code is adapted from fcr's des code Author: Shirish Koti 28-Feb-97 Revisions: --*/ /* * Sofware DES functions * written 12 Dec 1986 by Phil Karn, KA9Q; large sections adapted from * the 1977 public-domain program by Jim Gillogly */ // #include "compiler.h" #include //#include //#include //#define NULL 0 unsigned long byteswap(); CRITICAL_SECTION ArapDesLock; VOID des_done( IN VOID ); VOID des_setkey( IN PCHAR key // 64 bits (will use only 56) ); VOID des_endes( IN PCHAR block ); VOID des_dedes( IN PCHAR block ); static VOID permute( IN PCHAR inblock, // result into outblock,64 bits IN CHAR perm[16][16][8], // 2K bytes defining perm. IN PCHAR outblock // result into outblock,64 bits ); static VOID round( IN int num, IN unsigned long *block ); static long f (unsigned long r, unsigned char subkey[8]); static VOID perminit( IN CHAR perm[16][16][8], IN CHAR p[64] ); static int spinit(); PCHAR des_pw_bitshift( IN PCHAR pw ); PCHAR des_pw_bitshift_lowbit( IN PCHAR pw ); // // Tables defined in the Data Encryption Standard documents */ // // // initial permutation IP // static 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 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 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 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 char totrot[] = { 1,2,4,6,8,10,12,14,15,17,19,21,23,25,27,28 }; // // permuted choice key (table) // static 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 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 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() // static long (*sp)[64]; // Combined S and P boxes static char (*iperm)[16][8]; // Initial and final permutations static char (*fperm)[16][8]; // // 8 6-bit subkeys for each of 16 rounds, initialized by setkey() // static unsigned char (*kn)[8]; // // bit 0 is left-most in byte // static int bytebit[] = { 0200,0100,040,020,010,04,02,01 }; static int nibblebit[] = { 010,04,02,01 }; static int desmode; /* Allocate space and initialize DES lookup arrays * mode == 0: standard Data Encryption Algorithm * mode == 1: DEA without initial and final permutations for speed * mode == 2: DEA without permutations and with 128-byte key (completely * independent subkeys for each round) */ des_init(mode) int mode; { if(sp != NULL) { // Already initialized return 0; } desmode = mode; sp = (long (*)[64])LocalAlloc(LMEM_FIXED, (sizeof(long) * 8 * 64)); if(sp == NULL) { return -1; } spinit(); kn = (unsigned char (*)[8])LocalAlloc(LMEM_FIXED, (sizeof(char) * 8 * 16)); if(kn == NULL) { LocalFree((char *)sp); return -1; } if(mode == 1 || mode == 2) // No permutations return 0; iperm = (char (*)[16][8]) LocalAlloc(LMEM_FIXED, (sizeof(char) * 16 * 16 * 8)); if(iperm == NULL) { LocalFree((char *)sp); LocalFree((char *)kn); return -1; } perminit(iperm,ip); fperm = (char (*)[16][8]) LocalAlloc(LMEM_FIXED, (sizeof(char) * 16 * 16 * 8)); if(fperm == NULL) { LocalFree((char *)sp); LocalFree((char *)kn); LocalFree((char *)iperm); return -1; } perminit(fperm,fp); return 0; } // // Free up storage used by DES // VOID des_done( IN VOID ) { if(sp == NULL) return; // Already done LocalFree((char *)sp); LocalFree((char *)kn); if(iperm != NULL) LocalFree((char *)iperm); if(fperm != NULL) LocalFree((char *)fperm); sp = NULL; iperm = NULL; fperm = NULL; kn = NULL; } // // Set key (initialize key schedule array) // VOID des_setkey( IN PCHAR key // 64 bits (will use only 56) ) { char pc1m[56]; /* place to modify pc1 into */ char pcr[56]; /* place to rotate pc1 into */ register int i,j,l; int m; /* In mode 2, the 128 bytes of subkey are set directly from the * user's key, allowing him to use completely independent * subkeys for each round. Note that the user MUST specify a * full 128 bytes. * * I would like to think that this technique gives the NSA a real * headache, but I'm not THAT naive. */ if(desmode == 2) { for(i=0;i<16;i++) for(j=0;j<8;j++) kn[i][j] = *key++; return; } // // Clear key schedule // for (i=0; i<16; i++) for (j=0; j<8; j++) kn[i][j]=0; 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]=(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; kn[i][j/6] |= bytebit[l] >> 2; } } } } // // In-place encryption of 64-bit block // VOID des_endes( IN PCHAR block ) { register int i; unsigned long work[2]; /* Working data storage */ long tmp; permute(block,iperm,(char *)work); /* Initial Permutation */ work[0] = byteswap(work[0]); work[1] = byteswap(work[1]); /* Do the 16 rounds */ for (i=0; i<16; i++) round(i,work); /* Left/right half swap */ tmp = work[0]; work[0] = work[1]; work[1] = tmp; work[0] = byteswap(work[0]); work[1] = byteswap(work[1]); permute((char *)work,fperm,block); /* Inverse initial permutation */ } // // In-place decryption of 64-bit block // VOID des_dedes( IN PCHAR block ) { register int i; unsigned long work[2]; /* Working data storage */ long tmp; permute(block,iperm,(char *)work); /* Initial permutation */ work[0] = byteswap(work[0]); work[1] = byteswap(work[1]); /* Left/right half swap */ tmp = work[0]; work[0] = work[1]; work[1] = tmp; /* Do the 16 rounds in reverse order */ for (i=15; i >= 0; i--) round(i,work); work[0] = byteswap(work[0]); work[1] = byteswap(work[1]); permute((char *)work,fperm,block); /* Inverse initial permutation */ } PCHAR des_pw_bitshift( IN PCHAR pw ) { static char pws[8]; int i; /* key is null padded */ for (i = 0; i < 8; i++) pws[i] = 0; /* parity bit is always zero (this seem bogus) */ for (i = 0; i < 8 && pw[i]; i++) pws[i] = pw[i] << 1; return pws; } PCHAR des_pw_bitshift_lowbit( IN PCHAR pw ) { static char pws[8]; int i; /* key is null padded */ for (i = 0; i < 8; i++) pws[i] = 0; // In case of RandNum authentication, we need to drop the low bit! for (i = 0; i < 8 && pw[i]; i++) { pws[i] = (pw[i] & 0x7F); } return pws; } // // Permute inblock with perm // static VOID permute( IN PCHAR inblock, // result into outblock,64 bits IN CHAR perm[16][16][8], // 2K bytes defining perm. IN PCHAR outblock // result into outblock,64 bits ) { register int i,j; register char *ib, *ob; /* ptr to input or output block */ register char *p, *q; if(perm == NULL) { /* No permutation, just copy */ for(i=8; i!=0; i--) *outblock++ = *inblock++; return; } /* Clear output block */ for (i=8, ob = outblock; i != 0; i--) *ob++ = 0; ib = inblock; for (j = 0; j < 16; j += 2, ib++) /* for each input nibble */ { ob = outblock; p = perm[j][(*ib >> 4) & 017]; q = perm[j + 1][*ib & 017]; for (i = 8; i != 0; i--) /* and each output byte */ { *ob++ |= *p++ | *q++; /* OR the masks together*/ } } } // // Do one DES cipher round // static VOID round( IN int num, // i.e. the num-th one IN unsigned long *block ) { long f(); /* 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. */ if(num & 1) { block[1] ^= f(block[0],kn[num]); } else { block[0] ^= f(block[1],kn[num]); } } // // The nonlinear function f(r,k), the heart of DES // static long f(r,subkey) unsigned long r; /* 32 bits */ unsigned char subkey[8]; /* 48-bit key for this round */ { register unsigned long rval,rt; #ifdef TRACE unsigned char *cp; int i; 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. */ rt = (r >> 1) | ((r & 1) ? 0x80000000 : 0); rval = 0; rval |= sp[0][((rt >> 26) ^ *subkey++) & 0x3f]; rval |= sp[1][((rt >> 22) ^ *subkey++) & 0x3f]; rval |= sp[2][((rt >> 18) ^ *subkey++) & 0x3f]; rval |= sp[3][((rt >> 14) ^ *subkey++) & 0x3f]; rval |= sp[4][((rt >> 10) ^ *subkey++) & 0x3f]; rval |= sp[5][((rt >> 6) ^ *subkey++) & 0x3f]; rval |= sp[6][((rt >> 2) ^ *subkey++) & 0x3f]; rt = (r << 1) | ((r & 0x80000000) ? 1 : 0); rval |= sp[7][(rt ^ *subkey) & 0x3f]; #ifdef TRACE printf(" %08lx\n",rval); #endif return rval; } // // initialize a perm array // static VOID perminit( IN CHAR perm[16][16][8], // 64-bit, either init or final IN CHAR p[64] ) { register int l, j, k; int i,m; /* Clear the permutation array */ for (i=0; i<16; i++) for (j=0; j<16; j++) for (k=0; k<8; k++) perm[i][j][k]=0; 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 = p[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*/ perm[i][j][k>>3] |= bytebit[m]; } } // // Initialize the lookup table for the combined S and P boxes // static int spinit() { char pbox[32]; int p,i,s,j,rowcol; long 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] = (char)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]); } } sp[s][i] = val; #ifdef DEBUG printf("sp[%d][%2d] = %08lx\n",s,i,sp[s][i]); #endif } } return(0); } /* Byte swap a long */ static unsigned long byteswap(x) unsigned long x; { register char *cp,tmp; cp = (char *)&x; tmp = cp[3]; cp[3] = cp[0]; cp[0] = tmp; tmp = cp[2]; cp[2] = cp[1]; cp[1] = tmp; return x; } VOID DoTheDESEncrypt( IN OUT PCHAR ChallengeBuf ) { des_endes(ChallengeBuf); } VOID DoTheDESDecrypt( IN OUT PCHAR ChallengeBuf ) { des_dedes(ChallengeBuf); } VOID DoDesInit( IN PCHAR pClrTxtPwd, IN BOOLEAN DropHighBit // do we need to drop high bit in key-generation? ) { des_init(0); if (DropHighBit) { des_setkey(des_pw_bitshift(pClrTxtPwd)); } else { des_setkey(des_pw_bitshift_lowbit(pClrTxtPwd)); } } VOID DoDesEnd( IN VOID ) { des_done(); }