Hacker's Arsenal - The Cutting Edge of Hacking

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/***************************************************** Disclaimer: I take no responsibility for any damages the code in this tutorial May cause. This code has been run on my machine and others, and Should not contain errors. For your own personal safety, virus scan It first, as you should all files on the net *****************************************************/ 111111111111111111111111111111111111111111111111111111111 100000000000000000000000000000000000000000000000000000001 100000000000000000000000000000000000000000000000000000001 10000 00000000000000 00000000000000000000000000000001 100 00 0 00000000000000 0000000000 00000 0 0000001 100 00 000 0000000 0000 00000000 00000 0000 0 000 0000001 100 0000 00000 00000 0000000 0000000 000 0 000 0000001 100 00 000000 00 000000 0000000 0000000 000 0 000 0000001 100 00 0000000 0000000 0000000 0000000 000 0000 0000001 100 00 0000000 00 00000 00000000 00000 0000 00000 0000001 1000000000000 00000 000 000000000 000 00000 00000 0000001 100000000000 000000000 00000000 000000 00000 0000001 10000000000 000000000000000000000000000000000000000000001 100000000000000000000000000000000000000000000000000000001 111111111111111111111111111111111111111111111111111111111 Computer Encryption, an overview and programming. TOPICS: -255 1.0 - Encryption what is it? 1.1 - Is encryption even worthy? 1.2 - Yeah yeah, how do I encrypt stuff? 1.3 - Programming - Fundamentals 1.3.1 - Binary 1.3.2 - XOR, AND, ONES COMPLIMENTRY -Logical operators 1.3.3 - Structured C Programming. 9.9.9 - Encryption Example -255 Why are you reading this? Learn howto write efficient,structured encryption programs. Some programming knowledge is required, languages C/C++ will be fine. My homepage is: http://www.angelfire.com/sd/kias or visit my small asm tutorial http://www.angelfire.com/sd/kias/smart/ 1.0 Encryption, What is it? Encryption, what the hell? Yeah that's right, encryption. A Great Way to secure your privacy. Especially for all you l33t crack3rs out there. I know you want to jump to the programming so I'll just give you the Dictionary idea on what encryption is: 'Encrypt: 1. To put a message into code; 2. To put computer data into an encoded form 3. To get killed by a herd of killer monkeys. 4. yadadada ' Ok obviously it's not 1 or 2, so lets look at some reasons why 3 and 4 are Accurate! Ok, you just got a new computer and your now a leet user right? You download all the tools but theres one that catches your eye.. It asks you to enter the Filename of the file you want to encrypt so you do as it says, and pick your mums business file, work.dat it loads for a while and then says, encryption complete, you feel as though you could take on an army you feel leet. Two days later, your mum is unable to complete her job for work and loses her job, you innocently deny the events that fucked up her datafile. But deep down you feel guilty, you hate encryption and never want to see it again. Wrong! 'MOST' encryption programs are released with a 'de'Cryptor. !! You ARE able to turn mums work back into readable format! Unfortunately for this guy, he has no decryption and is banned from his computer for the rest of his teenage hood. Im not quite sure, but I think he got trampled by a herd of killer monkeys? Anyway, sorry for my insolent humor. I figured no one would read this part so if you are, I'm sorry =( Ok, encryption turns your mums great work files into useless code that's Unreadable, ready to continue on? 1.1 Is encryption even worthy? Answer: No Wrong Answer: It may come in handy if your cracking passwords etc or to protect email and stuff, but hey lets get with the times emails outdated. #35614954 for all you icq fans out there! 1.2 Yeah yeah how do I encrypt stuff? Its easy, download and run an encryption program. Parse all the correct parameters to the encryptor and WALA! If your using a good encryptor is should be able to DE-ENCRYPT in one! If you would like a FULLY WORKING ENCRYPTION PROGRAM refer to the example program at the bottom of this page! 1.3 Programming Fundamentals! Lets Pretend were writing an encryption program in 'English' it would look like this: ask for file1 to encrypt ask for file2 to output encrypted data too encrypt file1 and save as file2 leave file1 untouched Although this tutorial is C based, I will now show you a visual basic example followed by a C example for all of you without C experience. Ohh and for all of you with no experience, bye. Nah you can stay, maybe you'll learn something :) Visual Basic: private sub commandbutton1_click() dim file1,file2 as integer; ` I know this is wrong, but file1 = inputbox("File to Encrypt"); `were pretending... file2 = inputbox("File to output to"); `remember???? encrypt end sub END VISUAL Basic C: FILE *stream1,stream2; if((stream1 = fopen(argv[1], "rb")) == NULL) { /*ERROR*/ } if((stream2 = fopen(argv[2], "wb")) == NULL) { /* ERROR*/} encrypt(file1,file2); END C! Ok, if I have lost you. Read the next section otherwise skip it -=) NExt Section: stream1 and 2 are simply pointers to of type FILE argv[1] is the commandline parameter passed to programs in dos. example: program file1 file2 key file1 is argv[1] program is argv[0] file2 is argv[2] and key is argv[3] Ok so we know how to accept parameters! or do we? Here's an example help you understand: #include <stdio.h> int main(int argc, char *argv[]) { printf("Parameter 1 is %s, 2 is %s.\n", argv[1], argv[2]); printf("Program name is %s.\n", argv[0]; printf("Number of parameters: %d\n", argc); return 0; } Ok if it doesn't make sense, compile it with you favorite C compiler. Note: If you don't have a compiler, you obviously don't know how to program ? And this file may be a little extensive, programming wise for your liking. If you want keep reading feel free =) Note: The best way to learn is to teach people, so go and teach all your friends how to use argv and argc you'll be the coolest kid in school! I promise. 1.3.1 Binary Binary, hmmm and it would be? Answer: The only language the computer really understands. Although you may type some programs up and compile them, wether it be pascal,C,asm,delphi,vb,fortran or your dads billygoat your computer does not read what you tell it to, I know it sux, but its the truth. All your pretty little code is converted into a jumple of 1's and 0's. But you may protest, pfft what a load of shit, my programs contain advanced algorithms that couldnt possibly be defined with 1's and zero's. Wrong, every event which takes place on your computer is just a sequence of commands Heres an example that will enlighten you a little, the typical hello world program: int main() { while(1) printf("Hello, World!\n"); return 0; } This program is my enhancement to the original, this baby can produce 10000 Instances of hello world in under 1 minute! Actually, it simply loops for ever displaying the inevitable. Lets look at what really happens. Warning, ASM to follow: .data msg db "Hello, World!$",13,10 ; 13,10 is equivalent to \n .code START: mov ax, seg msg mov ds, ax mov dx, offset msg mov ah, 09 int 21h jmp START END START This program does exactly as the C program does, but you are able to see how it does what it does. Take attention to the jmp START instruction! Remember how a while loop loops until a condition is false? What you don't? Maybe that's because I haven't taught you yet. Here's the Catch. All it does is jmp to the start again, and executes all the instructions again! All this time you thought it involved magic etc. Pfft But you start to speak, "This 'aint' binary dude", yes indeed its not. But as you are about to find out, Your cute little C hello world program is converted to ASM so windows can run it! Computers are seriously stupid and only do what they are told. Ok, your asm code is then converted to 1's and 0's so the processor can read it. Do I see a pattern? Notepad.exe hello.c //code compiler asm operating system processor Ok, so now you see my point. Sorry i had to explain it for so long.. Some people just don't understand. If you still don't believe me, please do a suicide mission. j/k : "I am hereby responsible for no suicides that take place directly after the reading of this text" Now that we have that settled, lets learn some Binary! BINARY NUMBER SYSTEM: Decimal - Binary 1 0001 2 0010 3 0011 4 0100 5 0101 6 0110 7 0111 8 1000 16 10000 32 100000 64 1000000 128 10000000 256 100000000 Character - Decimal - Binary a 97 01100001 z 123 01111011 I'm sure you can figure the rest out.. :) Repeat to yourself, I now know binary! 1.3.2 Logical operator, AND, XOR, ONES COMPLIMENTARY Ok, in this section you need to know binary, so please read the above section LOGICAL 'AND' 1 0 1 1 0 0 0 0 LOGICAL 'XOR' 1 0 1 0 1 0 1 0 ONES COMPLIMENT '~' Example- Decimal: 21845 Binary: 01010101 01010101 ~Decimal: 42945450 Binary: 10101010 10101010 As above, we apply ~ to decimal 21845. It simply turns 1's to 0's and 0's to ones. TIP: Xor is good for encryption because applying it with the old value it was XORED with turns the bits back into their previous value: Example- We have two characters: 'a' and 'b' We want to encrypt 'a' by XORING the bits of 'b' into it. Do this: int encrypted; char a,b; a = 'a'; b = 'b'; encrypted = a ^ b; Which will yield this result: 'a' = 97 which is 01100001 in binary 'b' = 98 which is 01100010 encrypted now equals: 00000011 But were learning how to decrypt as well right? Sure are, to restore the value 'a' to its original unencrypted state we simple xor the encrypted value with 'b' again: int new; new = encrypted ^ b; which gives us this binary number: 01100001 which is, you guesses it, 'a'! So now we know the basic component behind the encryption of characters. Continue on to learn how to encrypt a whole file of strings, numbers etc. 1.3.3 Structured C Programming When writing code in any language it is important to write clear, efficient code that is well documented and easy to read, here are some tips: 1: To make readability of code easier, #define values at the start of the file that can be reused throughout the code, here's an example: #define SIZE 5 int array[SIZE] = {3,4,5,6,7}; 2: Try to use pointers wherever possible, observe: /* Pathetic version, recopies itself, inefficient */ --------------------------------------------- main() { int z; z = 10; func(z); // create copy of z two times. } int func(int value) { return = value * value; // return the square of a number } ---------------------------------------------- /* Good version, simply refers to memory locations, and does not copy variables, this is named, call by reference whereas the first version was call by value */ ---------------------------------------------- main() { int z = 10; func(&10); // reference z twice, efficient. } void func(unsigned *value) { *value *= *value; } ---------------------------------------------- 3: Allocate Memory Correctly: You could allocate 1000 of bytes like this, but you cannot free the used memory. int array[1000]; Try doing this, it really works! int *value; value = (int *) malloc(sizeof(int) * 4); free(value); Wow, efficient code, finally! 4: Indent your god damn programs!, please! Instead of this: int array[] = {3434,4545,34534,656, 23434,3454,45345,34535, 234,345345,345345,345,2435,3434, 34,345,566,5}; for(i = 0; i <= SIZE -1; i++ ) { sum += array[i] ; // add some more unreadable stuff... well this aint that good of example but its badly structured, observ the same code in structured format: int array[] = { 3434,4545,34534,656, 23434,3454,45345, 34535,234,345345, 345345,345,2435, 3434,34,345,566,5}; for (i = 0; i <= SIZE -1; i++) { sum += array[i]; //indent // some more // // // // // // // // // keep it up your going good! You can clearly see what I am on about, and be sure to fix small things like this, instead of while(!a=EOF)func1(val,val2,val3){i++;j++;g--;} do this: while (!a = EOF) func1(val, val2, val3) { i++; // increment i; j++; // dont add unnecessary comments g--; } 4: Ok nearly there, one last thing, add a signature, date etc. There's nothing better then seeing a great program, and seeing the authors name and contact so you can email them on there great efforts, BE MODEST! ACCEPT ALL RECOGNITION FOR YOUR masterpiece. A good signature is as follows: /****************************************** NAME: John Johnson EMAIL: john@cybernet.com ICQ: 35614954 DATE: 10/9/2000 *******************************************/ Wooooo I know its a big chunk to absorb, but absorb it damnit! Continue onto the next section, now that your efficient... :) 9.9.9 Encryption Example As I promised here's a budget example :) Remember the XOR operator ^ ? Xor operator == ^ in C :) Were going to write a small documented, structured program that will encrypt a file with the users key, the file can then be decrypted with the key. Otherwise the resulting file is encrypted again. The Encryption in this program is very weak, but to explain more complex algorithmic is too hard for now, maybe in my next article :) First, I will go over some features of this program that need be understood for all you wanna be crypotologists out there! Heres the code that loops through a file: while (c = getc(*file) != EOF) { encrypt() putc(*file,c) } // loop through *file until End of File is reached, each time // encrypting each character and incrementing it to the next character in // the file stream. Here's the algorithm Im using: c = c ^ *file2; counter++; That's it? Indeed it is, very small, very powerful.. Without further do, I represent a simple encryption program: ------------------------------------------- /****************************************************** Standard XOR Encryption By Axion UIN : 35614954 EMAIL: axionis@hotmail.com DATE : MAY 21st 2000 USAGE: xe filein fileout key *******************************************************/ #include <stdio.h> #define PROG_NAME "xe" void usage() { printf("-------------------------------\n"); printf("Invalid command line.\n"); printf("Usage:\n\t%s infile outfile key\n", PROG_NAME); printf("-------------------------------\n"); } int main(int argc, char *argv[]) { int count,bytes; /* counter when looping through file, and bytes to count filesize */ FILE *in,*out; /* In and out FILE Streams to read/write data */ if(argc < 4) { /* Error check the command line */ usage(); /* Display Usage Information on error */ return 0; /* Exit Program returning 0 - no error */ } if (( in = fopen(argv[1], "rb")) == NULL) /* Error Check File Streams */ { printf("Error opening %s.\n", argv[1]); } if (( out = fopen(argv[2], "wb")) == NULL) { printf("Error opening %s.\n", argv[2]); } while(( count = getc(in)) != EOF) { count = count ^ *argv[3]; /* Apply XOR ( KEY ) */ bytes++; /* Increment counter of filesize */ putc(count, out); /* Write new file */ } fclose(in); fclose(out); printf("Encryption Success:\n"); printf("\tEncrypted %s and stored data in %s.\n", argv[1],argv[2]); printf("\tWrote %d bytes to %s.\n", bytes,argv[2]); return 0; } /* To compile under djgpp */ /* dgjpp xe.c -o xe */ ------------------------------------------- Well that's it, my tutorial is almost complete..! But not without a few more challenges, exercises for the smart people: 1. Write an encryptor that uses one complimentary instead of Xor. 2. Write a program that uses two keys on a file. 3. Write a program that uses no logical operators ? HINT, refer to an ASCII character set. Lets assume, *s points to ASCII value 'a'. *s -= 31; turns it from 'a' to 'A' This should be enough to start you off on your quest. If anyone has any comments or would like to report any bugs write to axionis@hotmail.com or ICQ me on #35614954! Bye from me, hope to see you at the top.