How can I encrypt with AES in C# so I can decrypt it in PHP? -

i've found few answers encrypt in php, , decrypt in c#, yet have been unable reverse process...

the background want to:

in c#: aes encrypt file's contents. upload data (likely via http via post) server.

in php: receive , save file.

and in php (at later date): decrypt file.

i want encrypt outside of using ssl/tls (though might have well), need know file remains encrypted (and decryptable!) when stored on server.

to encrypt in c# i'm using:

rijndael rijndaelalg = rijndael.create(); rijndaelalg.keysize = 128; rijndaelalg.mode = ciphermode.cbc; cryptostream cstream = new cryptostream(fstream, rijndaelalg.createencryptor(key, iv),                                         cryptostreammode.read); 

and decrypt in php:

 mcrypt_cbc(mcrypt_rijndael_128, $key, $buffer, mcrypt_decrypt, $iv); 

generally depends on selecting right options on both sides:

• plaintext character format

  how plaintext characters encoded in bit string

• padding

  how pad plaintext exact multiple of block size

• key length

  must agreed if there choice

• key derivation

  how create bit string used key

• mode

  which mode of encryption use

• storage format

  how store ciphertext

please see here lot of information these things. padding seems root of interoperability problems php's mcrypt uses null-padding default , has no built-in support other padding mode, while e.g. .net doesn't provide option use null-padding (as may cause issues when encrypting binary data).