Encryption result is different on Android and IOS

[CDNRahulSonpaliya]

Hello,

I am using this library in my android project and its counter part https://github.com/Gurpartap/aescrypt in ios project. I am encrypting same text with same encryption key, but it is giving me different results on ios and android.

I am using this key : 25c35734b1ef623ca2a7f730cf2fea8b790739ba

String to encrypt is : Password

Encrypted String IOS : W3LyAxKq2+QdDBfKUGVgTg== Encrypted String Android : zdgSimKva1jblici7F8DGw==

[Rahulgupta-cdnsol]

Hi,

I am getting same issue with library as it is not generating same result as iOS.What needs to do to get similar result as iOS.

[ninjatrench]

Hi, I can look into it. Can you post the IV used by you in Android as well as iOS as iOS directly doesn't take blank IV

[Rahulgupta-cdnsol]

in IOS I am using below function :

• (NSData )doCipher:(NSData )plainText key:(NSData )aSymmetricKey context:(CCOperation)encryptOrDecrypt padding:(CCOptions )pkcs7{ CCCryptorStatus ccStatus = kCCSuccess; // Symmetric crypto reference. CCCryptorRef thisEncipher = NULL; // Cipher Text container. NSData * cipherOrPlainText = nil; // Pointer to output buffer. uint8_t * bufferPtr = NULL; // Total size of the buffer. size_t bufferPtrSize = 0;
  // Remaining bytes to be performed on. size_t remainingBytes = 0; // Number of bytes moved to buffer. size_t movedBytes = 0; // Length of plainText buffer. size_t plainTextBufferSize = 0; // Placeholder for total written. size_t totalBytesWritten = 0; // A friendly helper pointer. uint8_t * ptr;

  // Initialization vector; dummy in this case 0's. uint8_t iv[kChosenCipherBlockSize]; memset((void *) iv, 0x0, (size_t) sizeof(iv));

  // //NSLog(@"doCipher: plaintext: %@", plainText); // //NSLog(@"doCipher: key length: %d", [aSymmetricKey length]);

  plainTextBufferSize = [plainText length];

  if(encryptOrDecrypt == kCCEncrypt) { if(pkcs7 != kCCOptionECBMode) { if((plainTextBufferSize % kChosenCipherBlockSize) == 0) { pkcs7 = 0x0000; } else { pkcs7 = kCCOptionPKCS7Padding; } } } else if(encryptOrDecrypt != kCCDecrypt) { //NSLog(@"Invalid CCOperation parameter [%d] for cipher context.", pkcs7 ); }

  // Create and Initialize the crypto reference. ccStatus = CCCryptorCreate(encryptOrDecrypt, kCCAlgorithmAES128, pkcs7, (const void )[aSymmetricKey bytes], kChosenCipherKeySize, (const void *)iv, &thisEncipher );

  //LOGGING_FACILITY1( ccStatus == kCCSuccess, @"Problem creating the context, ccStatus == %d.", ccStatus );

  // Calculate byte block alignment for all calls through to and including final. bufferPtrSize = CCCryptorGetOutputLength(thisEncipher, plainTextBufferSize, true);

  // Allocate buffer. bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t) );

  // Zero out buffer. memset((void *)bufferPtr, 0x0, bufferPtrSize);

  // Initialize some necessary book keeping.

  ptr = bufferPtr;

  // Set up initial size. remainingBytes = bufferPtrSize;

  // Actually perform the encryption or decryption. ccStatus = CCCryptorUpdate(thisEncipher, (const void *) [plainText bytes], plainTextBufferSize, ptr, remainingBytes, &movedBytes );

  //LOGGING_FACILITY1( ccStatus == kCCSuccess, @"Problem with CCCryptorUpdate, ccStatus == %d.", ccStatus );

  // Handle book keeping. ptr += movedBytes; remainingBytes -= movedBytes; totalBytesWritten += movedBytes;

  /* From CommonCryptor.h:

  @enum CCCryptorStatus @abstract Return values from CommonCryptor operations.

  @constant kCCSuccess Operation completed normally. @constant kCCParamError Illegal parameter value. @constant kCCBufferTooSmall Insufficent buffer provided for specified operation. @constant kCCMemoryFailure Memory allocation failure. @constant kCCAlignmentError Input size was not aligned properly. @constant kCCDecodeError Input data did not decode or decrypt properly. @constant kCCUnimplemented Function not implemented for the current algorithm.

  enum { kCCSuccess = 0, kCCParamError = -4300, kCCBufferTooSmall = -4301, kCCMemoryFailure = -4302, kCCAlignmentError = -4303, kCCDecodeError = -4304, kCCUnimplemented = -4305 }; typedef int32_t CCCryptorStatus; */

  // Finalize everything to the output buffer. ccStatus = CCCryptorFinal(thisEncipher, ptr, remainingBytes, &movedBytes );

  totalBytesWritten += movedBytes;

  if(thisEncipher) { (void) CCCryptorRelease(thisEncipher); thisEncipher = NULL; }

  //LOGGING_FACILITY1( ccStatus == kCCSuccess, @"Problem with encipherment ccStatus == %d", ccStatus );

  if (ccStatus == kCCSuccess) cipherOrPlainText = [NSData dataWithBytes:(const void *)bufferPtr length:(NSUInteger)totalBytesWritten]; else cipherOrPlainText = nil;

  if(bufferPtr) free(bufferPtr);

  return cipherOrPlainText;

} Android :- byte[] ivBytes = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};