OSX/libsecurity_cryptkit/lib/NSDESCryptor.m

   1 /* Copyright (c) 1998,2011,2014 Apple Inc.  All Rights Reserved.
   2  *
   3  * NOTICE: USE OF THE MATERIALS ACCOMPANYING THIS NOTICE IS SUBJECT
   4  * TO THE TERMS OF THE SIGNED "FAST ELLIPTIC ENCRYPTION (FEE) REFERENCE
   5  * SOURCE CODE EVALUATION AGREEMENT" BETWEEN APPLE, INC. AND THE
   6  * ORIGINAL LICENSEE THAT OBTAINED THESE MATERIALS FROM APPLE,
   7  * INC.  ANY USE OF THESE MATERIALS NOT PERMITTED BY SUCH AGREEMENT WILL
   8  * EXPOSE YOU TO LIABILITY.
   9  ***************************************************************************
  10  *
  11  * NSDESCryptor.m - DES encrypt/decrypt class
  12  *
  13  * Revision History
  14  * ----------------
  15  * 28 Mar 97 at Apple
  16  *      Rewrote using feeDES module.
  17  * 22 Feb 96 at NeXT
  18  *      Created.
  19  */
  20
  21 #import <Foundation/Foundation.h>
  22 #import "NSDESCryptor.h"
  23 #import "feeDES.h"
  24 #import "falloc.h"
  25 #import "ckutilities.h"
  26 #import "feeFunctions.h"
  27
  28 /*
  29  * Note: Our _priv ivar is actuall a feeDES pointer.
  30  */
  31 @implementation NSDESCryptor
  32
  33 + cryptorWithState:(NSData *)s {
  34     return [[[self alloc] initWithState:s] autorelease];
  35 }
  36
  37 - (void)setCryptorState:(NSData *)state {
  38     if(_priv == NULL) {
  39         return;
  40     }
  41     feeDESSetState(_priv, [state bytes], [state length]);
  42 }
  43
  44 - initWithState:(NSData *)state {
  45     feeReturn   frtn;
  46
  47     if(_priv == NULL) {
  48         _priv = feeDESNewWithState([state bytes], [state length]);
  49     }
  50     else {
  51         frtn = feeDESSetState(_priv, [state bytes], [state length]);
  52         if(frtn) {
  53             NSLog(@"NSDESCryptor: bad initial state\n");
  54             return nil;
  55         }
  56     }
  57     return self;
  58 }
  59
  60 - (void)dealloc
  61 {
  62         if(_priv) {
  63                 feeDESFree(_priv);
  64         }
  65         [super dealloc];
  66 }
  67
  68 - (void)setBlockMode:(BOOL)yorn {
  69     if(_priv == NULL) {
  70         return;
  71     }
  72     if(yorn) {
  73         feeDESSetBlockMode(_priv);
  74     }
  75     else {
  76         feeDESSetChainMode(_priv);
  77     }
  78 }
  79
  80 - (NSData *)encryptData:(NSData *)input {
  81     NSData              *result;
  82     feeReturn           frtn;
  83     unsigned char       *cipherText;
  84     unsigned            cipherTextLen;
  85
  86     if(_priv == NULL) {
  87         return nil;
  88     }
  89     frtn = feeDESEncrypt(_priv,
  90         [input bytes],
  91         [input length],
  92         &cipherText,
  93         &cipherTextLen);
  94     if(frtn) {
  95         NSLog(@"NSDESCryptor encrypt: %s", feeReturnString(frtn));
  96         return nil;
  97     }
  98     result = [NSData dataWithBytes:cipherText length:cipherTextLen];
  99     ffree(cipherText);
 100     return result;
 101 }
 102
 103 - (NSData *)decryptData:(NSData *)input {
 104     NSData              *result;
 105     feeReturn           frtn;
 106     unsigned char       *plainText;
 107     unsigned            plainTextLen;
 108
 109     if(_priv == NULL) {
 110         return nil;
 111     }
 112     frtn = feeDESDecrypt(_priv,
 113         [input bytes],
 114         [input length],
 115         &plainText,
 116         &plainTextLen);
 117     if(frtn) {
 118         NSLog(@"NSDESCryptor decrypt: %s", feeReturnString(frtn));
 119         return nil;
 120     }
 121     result = [NSData dataWithBytes:plainText length:plainTextLen];
 122     ffree(plainText);
 123     return result;
 124 }
 125
 126 - (unsigned)keyBitsize {
 127         return feeDESKeySize(_priv);
 128 }
 129
 130 @end