objective c - Can I use a key with 33-bytes in AES256 -

my friend wrote 2 methods aes256 objective-c. length of key kcckeysizeaes256+1 = 33 bytes

now need port 2 methods language such java, php, go. other languages don't accept 33-byte key

i can not change objective-c code because ios app online users.

please me port these 2 methods languages!!! (i hate friend)

objective-c methods:

nsdata * aes256encryptwith(nsdata *data, nsstring *key){     // 'key' should 32 bytes aes256, null-padded otherwise     char keyptr[kcckeysizeaes256+1]; // room terminator (unused)     bzero(keyptr, sizeof(keyptr)); // fill zeroes (for padding)      // fetch key data     [key getcstring:keyptr maxlength:sizeof(keyptr) encoding:nsutf8stringencoding];      nsuinteger datalength = [data length];      //see doc: block ciphers, output size less or     //equal input size plus size of 1 block.     //that's why need add size of 1 block here     size_t buffersize = datalength + kccblocksizeaes128;     void *buffer = malloc(buffersize);      size_t numbytesencrypted = 0;     cccryptorstatus cryptstatus = cccrypt(kccencrypt, kccalgorithmaes128, kccoptionpkcs7padding,                                           keyptr, kcckeysizeaes256,                                           null /* initialization vector (optional) */,                                           [data bytes], datalength, /* input */                                           buffer, buffersize, /* output */                                           &numbytesencrypted);     if (cryptstatus == kccsuccess) {         //the returned nsdata takes ownership of buffer , free on deallocation         return [nsdata datawithbytesnocopy:buffer length:numbytesencrypted];     }      free(buffer); //free buffer;     return nil; }  nsdata * aes256decryptwith(nsdata *data, nsstring *key){     // 'key' should 32 bytes aes256, null-padded otherwise     char keyptr[kcckeysizeaes256+1]; // room terminator (unused)     bzero(keyptr, sizeof(keyptr)); // fill zeroes (for padding)      // fetch key data     [key getcstring:keyptr maxlength:sizeof(keyptr) encoding:nsutf8stringencoding];      nsuinteger datalength = [data length];      //see doc: block ciphers, output size less or     //equal input size plus size of 1 block.     //that's why need add size of 1 block here     size_t buffersize = datalength + kccblocksizeaes128;     void *buffer = malloc(buffersize);      size_t numbytesdecrypted = 0;     cccryptorstatus cryptstatus = cccrypt(kccdecrypt, kccalgorithmaes128, kccoptionpkcs7padding,                                           keyptr, kcckeysizeaes256,                                           null /* initialization vector (optional) */,                                           [data bytes], datalength, /* input */                                           buffer, buffersize, /* output */                                           &numbytesdecrypted);      if (cryptstatus == kccsuccess) {         //the returned nsdata takes ownership of buffer , free on deallocation         return [nsdata datawithbytesnocopy:buffer length:numbytesdecrypted];     }      free(buffer); //free buffer;     return nil; } 

you should read comments in code... uses 32 bytes key. last byte string terminator... should use first 32 bytes 33byte key.

aes256 works 32bytes (which ist 256 bit)