c# - Secure XOR encryption attempt -

this first post , sorry if made errors format.

i trying write program encrypt kinds of file via xor in secure way. know xor isn't secure encryption method wanted give try. please have on methode , tell me if complete bullshit or not :) password string, chosen user. in beginning xored file password, leading easy decryption if parts of password guessed correctly.

here procedure:

1. tmpfile = file xor (hash of password combined pw.length.tostring) //to make sure password elements in right order
2. tmpfile = tmpfile xor (xor byte composed each byte of password)//ensure password decode has right chars.
3. tmpfile= tmpfile xor initial_password

could encrypted text decrypted self-xor-shifting technique?

thanks advice! :)

edit: here code:

using system; using system.collections.generic; using system.linq; using system.text; using system.threading.tasks; using system.security; using system.io; using system.windows;  namespace encodeeverything {     class program     {          static void main(string[] args)         {             console.writeline("fileencrypter v01 \n \n");                   //get password                 console.writeline("enter password (encryption key)");                 string password = getpassword();                 console.writeline("");              while (true)             {                  console.writeline("");                 console.writeline("-----------------------");                 console.writeline("");                  //get file encrypt                 console.writeline("file encrypt/decrypt:");                  console.write("  ");                 string path = console.readline();                  //-------------------------------                 //load, encrypt & save file                 //-------------------------------                 try {                     byte[] tmpbarr = encrypt(file.readallbytes(path), getcustomhash(password));                     file.writeallbytes(path, encrypt(tmpbarr, password));                     console.writeline("    done.");                 }                 catch(system.exception e)                 {                     console.writeline("!! error while processing. path correct? !!");                 }              }         }         private static string getcustomhash(string word)         {             string output = "";              output += word.length.tostring();             output += word.gethashcode();              return output;         }          //encrypt bzw decrypt byte[]         public static byte[] encrypt(byte[] s, string key)         {             list<byte> output = new list<byte>();             byte[] codeword = encoding.utf8.getbytes(key);              byte keybyte =(byte)( codeword[0]^ codeword[0]);             foreach(byte b in codeword)             {                 keybyte = (byte)(b ^ keybyte);             }              (int = 0; < s.length; i++)             {                 output.add((byte)(s[i] ^ codeword[i % codeword.length] ^ keybyte));             }              return output.toarray();         }            public static string getpassword()         {             console.write("  ");              string pwd = "";             while (true)             {                 consolekeyinfo = console.readkey(true);                 if (i.key == consolekey.enter)                 {                     break;                 }                 else if (i.key == consolekey.backspace)                 {                     if (pwd.length > 0)                     {                         pwd= pwd.remove(pwd.length - 1);                         console.write("\b \b");                     }                 }                 else                 {                     pwd+=(i.keychar);                     console.write("*");                 }             }             return pwd;         }      } } 

you can ignore answer if you're trying encrypt files learning exercise in cryptography, if you're looking real-world solution securing file data, read on.

i'd recommend use file encryption built .net framework sort of thing if you're looking real-world solution keeping file data secure.

from microsoft @ https://msdn.microsoft.com/en-us/library/system.io.file.encrypt(v=vs.110).aspx

using system; using system.io; using system.security.accesscontrol;  namespace filesystemexample {     class fileexample     {         public static void main()         {             try             {                 string filename = "test.xml";                  console.writeline("encrypt " + filename);                  // encrypt file.                 addencryption(filename);                  console.writeline("decrypt " + filename);                  // decrypt file.                 removeencryption(filename);                  console.writeline("done");             }             catch (exception e)             {                 console.writeline(e);             }              console.readline();         }           // encrypt file.         public static void addencryption(string filename)         {              file.encrypt(filename);          }          // decrypt file.         public static void removeencryption(string filename)         {             file.decrypt(filename);         }     } } 

it hard sure need, because other things may need taken consideration such whether need pass file between different clients/servers etc, how data you're encrypting in each file.

again, if you're looking real-world cryptography using c#, can't stress enough should looking built-in .net encryption rather trying roll own- if don't have formal training in subject matter. recommend pore through microsoft documentation on .net framework encryption if you're interested in securing data in production:

https://msdn.microsoft.com/en-us/library/0ss79b2x(v=vs.110).aspx

here nice walkthrough creating example file encrypting windows form application:

https://msdn.microsoft.com/en-us/library/bb397867(v=vs.110).aspx