PHP Encrypting File

Make a PHP file that can be included with our existing project. The PHP file will encrypt 720 files, usually begin with for($i=1;$i<721:$i++){ $file[$i] = .......; $handle[$i]=fopen($file[$i],'r+'); .... } You should have some knowledge on hexadecimal. Here are the information that will help you through making this project: -Each file that is to be encrypted are 136 bytes. -The last 128 bytes are to be encrypted and the first 8 bytes will remain the same -Each block is exactly 32 byte, Block A: 0x08-0x27, Block B: 0x28-0x47, Block C: 0x48-0x67, Block D: 0x68-0x87 Here is how block shuffling work: $pid = hexdec(bin2hex(strrev(file_get_contents($file,NULL,NULL,0x0,4)))); $pv = (($pid & 0x3E000) >> 0xD) % 24; If PV Block Order 00 ABCD 01 ABDC 02 ACBD 03 ACDB 04 ADBC 05 ADCB 06 BACD 07 BADC 08 BCAD 09 BCDA 10 BDAC 11 BDCA 12 CABD 13 CADB 14 CBAD 15 CBDA 16 CDAB 17 CDBA 18 DABC 19 DACB 20 DBAC 21 DBCA 22 DCAB 23 DCBA *** To encrypt the data: -Shuffle the blocks using the block shuffling algorithm above. -Seed the PRNG with the checksum (let X[n] be the checksum), (Note: checksum is located at 0x06-0x07 -Sequentially, for each 2-byte word Y from 0x08 to 0x87, apply the transformation: unencryptedByte = Y xor rand() This project should take approximately 30 min to be done, however we allow one week or more time as you request.