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About LinkBacks
Request For Comments - Simple Encryption.
I've been working on an Stream Cipher for about 2 weeks and I've gotten along way
I'm going to use this to protect files with my Check Book Program. At the request of a few friends.
Good, Bad, Ugly. What Do you Think?
I like ALL feedback.
Full Source zip is available with VS2003 Solution and project files.
Sorry but I don't have my 'make' file handy I'll load it onto my web server as soon as I get a chance.
Full Source
SimpleCipher_v0.1.zip
For the Winzip Impaired I've setup a Folder Containing all the files
SimpleCipher_v0.1/
If the links stop working then check it out here.
http://thedivinedude.home.comcast.net
This code works great on my
Mandrake Linux 32bit,
Slackware 12 Linux 32bit,
Windows Vista 64bit,
Windows Vista 32,
Windows XP,
Windows 98
I can encode a message on any machine and it be read without problems on the others.
I've been developing with Visual Studio 2003.net
And I've had no problems building under GCC g++ version 4.3.3
Red shows where i've made changes 2-16-09
SimpleCypher.h
SimpleCipher.cppCode:#pragma once #define CIPHER_ROUNDS 16 #include <iostream> //#include "MyFileBuffer.h" class SimpleCipher { public: SimpleCipher(void); ~SimpleCipher(void); void makeKey(unsigned char* key, size_t length); unsigned char* makeKeyFile(unsigned char* key, size_t keylength, size_t count); void cipher(void* data, size_t length); void encrypt(void* data, size_t length); void decrypt(void* data, size_t length); private: unsigned char ring_a[8]; unsigned char ring_b[8]; unsigned char ring_c[8]; unsigned char s_box[256]; size_t counter_a, counter_b, counter_c; size_t a,b,c; unsigned char* _key; size_t _length; bool _lock; unsigned char rand(); void shiftbit(unsigned char* ring); void MakeCheckSum(unsigned char* checksum, const void* data, unsigned int size); };
Code:#include ".\simplecipher.h" void SimpleCipher::shiftbit(unsigned char* ring){ unsigned __int32 temp[2]; unsigned __int32* p = (unsigned __int32*) ring; temp[0] = (*p) >> 1; p++; temp[1] = (*p) >> 1; p--; temp[1] |= (*p) << 31; p++; temp[0] |= (*p) << 31; *p = temp[1]; p--; *p = temp[0]; } void SimpleCipher::MakeCheckSum(unsigned char* checksum, const void* data, unsigned int size) { //error check if(checksum == NULL) return; if(data == NULL) return; if(size == 0 ) return; unsigned char temp, carry; unsigned char* d = (unsigned char*)data; unsigned char* p; carry = 0; do{ temp = *d; temp ^= carry; p = checksum; p += 7; *p += (temp & 0x01); p--; temp >>= 1; *p += (temp & 0x01); p--; temp >>= 1; *p += (temp & 0x01); p--; temp >>= 1; *p += (temp & 0x01); p--; temp >>= 1; *p += (temp & 0x01); p--; temp >>= 1; *p += (temp & 0x01); p--; temp >>= 1; *p += (temp & 0x01); p--; temp >>= 1; *p += (temp & 0x01); d++; size--; carry ^= ( checksum[0] ^ checksum[1] ^ checksum[2] ^ checksum[3] ^ checksum[4] ^ checksum[5] ^ checksum[6] ^ checksum[7]); shiftbit(checksum); }while(size); } SimpleCipher::SimpleCipher(void) { _lock = false; _key = 0; _length = 0; } SimpleCipher::~SimpleCipher(void) { if(_key) delete _key; } void SimpleCipher::makeKey(unsigned char* key, size_t length){ unsigned char temp; if(_key) delete _key; _key = new unsigned char[length]; if(!_key) return; _length = length; this->counter_a = 64; this->counter_b = 64; this->counter_c = 64; this->a = 0; this->b = 0; this->c = 0; memset(&ring_a[0], 0, 8); memset(&ring_b[0], 0, 8); memset(&ring_c[0], 0, 8); //Make key from user input. for(int x = 0; x != 255; x++){ MakeCheckSum(&ring_a[0], key, length); MakeCheckSum(&ring_b[0], &ring_a[0], 8); MakeCheckSum(&ring_c[0], &ring_b[0], 8); MakeCheckSum(&ring_a[0], &ring_c[0], 8); } //Prep s_boxes for(int x = 0; x != 256; x++) s_box[x] = x; _lock = true; for(int x = 0; x != 256; x++){ temp = this->rand(); for(int y = 0; y != 256; y++){ s_box[y] ^= temp; rand(); } } this->encrypt(_key, _length); _lock = false; } unsigned char* SimpleCipher::makeKeyFile(unsigned char* key, size_t keylength, size_t count){ return 0; } void SimpleCipher::cipher(void* data, size_t length){ unsigned char* p = (unsigned char*)data; for(;length != 0;length--,p++) *p ^= this->rand(); } void SimpleCipher::encrypt(void* data, size_t length){ unsigned char* p = (unsigned char*)data; for( ;length;length--){ for(int x=0; x != CIPHER_ROUNDS; x++){ *p += this->rand(); *p = s_box[(*p)]; *p -= s_box[this->rand()]; *p ^= this->rand(); } p++; } } void SimpleCipher::decrypt(void* data, size_t length){ unsigned char temp[CIPHER_ROUNDS*3], *p; unsigned char s[256]; p = (unsigned char*)data; for(int x = 0; x != 256; x++) s[s_box[x]] = x; for(;length;length--){ for(int x = 0; x != CIPHER_ROUNDS*3; x++) temp[x] = this->rand(); for(int x = CIPHER_ROUNDS*3-1; x >= 0; x-=3){ *p ^= temp[x]; *p += s_box[temp[x-1]]; *p = s[(*p)]; *p -= temp[x-2]; } p++; } } unsigned char SimpleCipher::rand(){ unsigned char result; a = (ring_a[c] & 0x07); b = (ring_b[a] & 0x07); c = (ring_c[b] & 0x07); result = ring_a[a] ^ ring_b[b] ^ ring_c[c]; shiftbit(&ring_c[0]); counter_c--; if(counter_c == 0){ counter_c = 64; shiftbit(&ring_b[0]); counter_b--; if(counter_b == 0){ counter_b = 64; shiftbit(&ring_a[0]); counter_a++; if(counter_a == 0){ counter_a = 64; if(!_lock){ _lock = true; for(int x = CIPHER_ROUNDS; x; x--){ this->encrypt(_key, _length); MakeCheckSum(&ring_a[0], _key, _length); MakeCheckSum(&ring_b[0], &ring_a[0], 8); MakeCheckSum(&ring_c[0], &ring_b[0], 8); MakeCheckSum(&ring_a[0], &ring_c[0], 8); } _lock = false; } } } } return result; }
Originally Posted by laserlight 
