/*--- newdes2.c -- Program to implement the NEWDES algorithm. * * See Robert Scott's article "Wide-open Encryption Design Offers * Flexible Implementations" in Volume 9, Number 1 (January 1985) * of Cryptologia. * This algorithm resembles the Data Encryption Standard, but is easier * to implement in software and is supposed to be more secure. * * Based on my March 1988 8086 assembly language version. * * Mark Riordan 12 August 1990. */ #include "newdes2p.h" #define SIZE_ROTOR 256 #define SIZE_KEY_UNRAV 60 #define SIZE_USER_KEY 15 #define BLOCK_BYTES 8 #if 0 unsigned int newdes_buf(unsigned char *buf,unsigned int block_length); void newdes_block(unsigned char *block); void newdes_set_key_encipher(unsigned char *key); void newdes_set_key_decipher(unsigned char *key); #endif unsigned char newdes_rotor[SIZE_ROTOR] = { 32,137,239,188,102,125,221, 72,212, 68, 81, 37, 86,237,147,149, 70,229, 17,124,115,207, 33, 20,122,143, 25,215, 51,183,138,142, 146,211,110,173, 1,228,189, 14,103, 78,162, 36,253,167,116,255, 158, 45,185, 50, 98,168,250,235, 54,141,195,247,240, 63,148, 2, 224,169,214,180, 62, 22,117,108, 19,172,161,159,160, 47, 43,171, 194,175,178, 56,196,112, 23,220, 89, 21,164,130,157, 8, 85,251, 216, 44, 94,179,226, 38, 90,119, 40,202, 34,206, 35, 69,231,246, 29,109, 74, 71,176, 6, 60,145, 65, 13, 77,151, 12,127, 95,199, 57,101, 5,232,150,210,129, 24,181, 10,121,187, 48,193,139,252, 219, 64, 88,233, 96,128, 80, 53,191,144,218, 11,106,132,155,104, 91,136, 31, 42,243, 66,126,135, 30, 26, 87,186,182,154,242,123, 82,166,208, 39,152,190,113,205,114,105,225, 84, 73,163, 99,111, 204, 61,200,217,170, 15,198, 28,192,254,134,234,222, 7,236,248, 201, 41,177,156, 92,131, 67,249,245,184,203, 9,241, 0, 27, 46, 133,174, 75, 18, 93,209,100,120, 76,213, 16, 83, 4,107,140, 52, 58, 55, 3,244, 97,197,238,227,118, 49, 79,230,223,165,153, 59 }; unsigned char newdes_key_unravelled[SIZE_KEY_UNRAV]; /*--- function newdes_buf ------------------------------------------- * * Encipher or decipher a buffer of data. * * Entry buf points to the buffer. * block_length is the number of bytes in the buffer. * If it is not a multiple of 8, it will be * rounded up to the next multiple of 8-- * so make sure that the buffer is long enough. * newdes_key_unravelled points to the key. It has * been "unravelled" as necessary for either * enciphering or deciphering. * newdes_rotor is the fundamental mapping function * (array) for NEWDES. * * Exit Returns the number of bytes now in the buffer * (rounded up as described above). */ unsigned int newdes_buf(buf,block_length) unsigned char *buf; unsigned int block_length; { unsigned int mylen, mylen2; if(block_length > 0) { mylen2 = mylen = (((block_length - 1) / BLOCK_BYTES) + 1) * BLOCK_BYTES; } for(;mylen; mylen -= BLOCK_BYTES){ newdes_block(buf); buf += BLOCK_BYTES; } return(mylen2); } /*--- function newdes_block ----------------------------------------- * * Encipher or decipher an 8-byte block. * * Entry block points to the block. * newdes_key_unravelled points to the key. It has * been "unravelled" as necessary for either * enciphering or deciphering. * newdes_rotor is the fundamental mapping function * (array) for NEWDES. */ void newdes_block(block) unsigned char *block; { unsigned char *keyptr = newdes_key_unravelled; register unsigned char *byteptr = block; int count; #define B0 (*byteptr) #define B1 (*(byteptr+1)) #define B2 (*(byteptr+2)) #define B3 (*(byteptr+3)) #define B4 (*(byteptr+4)) #define B5 (*(byteptr+5)) #define B6 (*(byteptr+6)) #define B7 (*(byteptr+7)) for(count=8; count--;) { B4 = B4 ^ newdes_rotor[B0 ^ *(keyptr++)]; B5 = B5 ^ newdes_rotor[B1 ^ *(keyptr++)]; B6 = B6 ^ newdes_rotor[B2 ^ *(keyptr++)]; B7 = B7 ^ newdes_rotor[B3 ^ *(keyptr++)]; B1 = B1 ^ newdes_rotor[B4 ^ *(keyptr++)]; B2 = B2 ^ newdes_rotor[B4 ^ B5]; B3 = B3 ^ newdes_rotor[B6 ^ *(keyptr++)]; B0 = B0 ^ newdes_rotor[B7 ^ *(keyptr++)]; } B4 = B4 ^ newdes_rotor[B0 ^ *(keyptr++)]; B5 = B5 ^ newdes_rotor[B1 ^ *(keyptr++)]; B6 = B6 ^ newdes_rotor[B2 ^ *(keyptr++)]; B7 = B7 ^ newdes_rotor[B3 ^ *(keyptr++)]; } /*--- function newdes_set_key_encipher --------------------------------- * * Set newdes to encipher using a given key. * * Entry key points to a 15-byte key. * * Exit newdes_key_unravelled contains the key set up properly * for use in newdes_block, for enciphering. */ void newdes_set_key_encipher(key) unsigned char *key; { unsigned char *kuserptr, *kunravptr; int outloopct = SIZE_KEY_UNRAV / SIZE_USER_KEY; int inloopct; kunravptr = newdes_key_unravelled; for(;outloopct--;) { kuserptr = key; for(inloopct=SIZE_USER_KEY; inloopct--;) { *(kunravptr++) = *(kuserptr++); } } } /*--- function newdes_set_key_decipher --------------------------------- * * Set newdes to decipher using a given key. * * Entry key points to a 15-byte key. * * Exit newdes_key_unravelled contains the key set up properly * for use in newdes_block, for deciphering. */ void newdes_set_key_decipher(key) unsigned char *key; { unsigned char *kunravptr; int outloopct = SIZE_KEY_UNRAV / SIZE_USER_KEY; int userkeyidx; kunravptr = newdes_key_unravelled; userkeyidx = 11; while (1) { *(kunravptr++) = key[userkeyidx]; userkeyidx++; if(userkeyidx == SIZE_USER_KEY) userkeyidx = 0; *(kunravptr++) = key[userkeyidx]; userkeyidx++; if(userkeyidx == SIZE_USER_KEY) userkeyidx = 0; *(kunravptr++) = key[userkeyidx]; userkeyidx++; if(userkeyidx == SIZE_USER_KEY) userkeyidx = 0; *(kunravptr++) = key[userkeyidx]; userkeyidx = (userkeyidx+9) % 15; if(userkeyidx == 12) break; *(kunravptr++) = key[userkeyidx++]; *(kunravptr++) = key[userkeyidx++]; *(kunravptr++) = key[userkeyidx]; userkeyidx = (userkeyidx+9) % 15; } }