ios aes加密（转）

最新推荐文章于 2022-01-18 13:24:01 发布

转载最新推荐文章于 2022-01-18 13:24:01 发布 · 98 阅读

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CC 4.0 BY-SA版权

原文链接：http://www.cnblogs.com/pengyingh/articles/4788851.html

参看：https://github.com/Gurpartap/AESCrypt-ObjC

AESCrypt.h

//
//  AESCrypt.h
//  Gurpartap Singh
//
//  Created by Gurpartap Singh on 06/05/12.
//  Copyright (c) 2012 Gurpartap Singh
// 
//     MIT License
// 
//     Permission is hereby granted, free of charge, to any person obtaining
//     a copy of this software and associated documentation files (the
//     "Software"), to deal in the Software without restriction, including
//     without limitation the rights to use, copy, modify, merge, publish,
//     distribute, sublicense, and/or sell copies of the Software, and to
//     permit persons to whom the Software is furnished to do so, subject to
//     the following conditions:
// 
//     The above copyright notice and this permission notice shall be
//     included in all copies or substantial portions of the Software.
// 
//     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
//     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
//     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
//     LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
//     OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
//     WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

#import <Foundation/Foundation.h>

@interface AESCrypt : NSObject

+ (NSString *)encrypt:(NSString *)message password:(NSString *)password;
+ (NSString *)decrypt:(NSString *)base64EncodedString password:(NSString *)password;

@end

AESCrypt.m

//
//  AESCrypt.m
//  Gurpartap Singh
//
//  Created by Gurpartap Singh on 06/05/12.
//  Copyright (c) 2012 Gurpartap Singh
// 
//     MIT License
// 
//     Permission is hereby granted, free of charge, to any person obtaining
//     a copy of this software and associated documentation files (the
//     "Software"), to deal in the Software without restriction, including
//     without limitation the rights to use, copy, modify, merge, publish,
//     distribute, sublicense, and/or sell copies of the Software, and to
//     permit persons to whom the Software is furnished to do so, subject to
//     the following conditions:
// 
//     The above copyright notice and this permission notice shall be
//     included in all copies or substantial portions of the Software.
// 
//     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
//     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
//     MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
//     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
//     LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
//     OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
//     WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

#import "AESCrypt.h"

#import "NSData+Base64.h"
#import "NSString+Base64.h"
#import "NSData+CommonCrypto.h"

@implementation AESCrypt

+ (NSString *)encrypt:(NSString *)message password:(NSString *)password {
  NSData *encryptedData = [[message dataUsingEncoding:NSUTF8StringEncoding] AES256EncryptedDataUsingKey:[[password dataUsingEncoding:NSUTF8StringEncoding] SHA256Hash] error:nil];
  NSString *base64EncodedString = [NSString base64StringFromData:encryptedData length:[encryptedData length]];
  return base64EncodedString;
}

+ (NSString *)decrypt:(NSString *)base64EncodedString password:(NSString *)password {
  NSData *encryptedData = [NSData base64DataFromString:base64EncodedString];
  NSData *decryptedData = [encryptedData decryptedAES256DataUsingKey:[[password dataUsingEncoding:NSUTF8StringEncoding] SHA256Hash] error:nil];
  return [[NSString alloc] initWithData:decryptedData encoding:NSUTF8StringEncoding];
}

@end

NSData+Base64.h

//
//  NSData+Base64.m
//  Gurpartap Singh
//
//  Created by Gurpartap Singh on 06/05/12.
//  Copyright (c) 2012 Gurpartap Singh. All rights reserved.
//

#import <Foundation/Foundation.h>

@class NSString;

@interface NSData (Base64Additions)

+ (NSData *)base64DataFromString:(NSString *)string;

@end

NSData+Base64.m

//
//  NSData+Base64.h
//  Gurpartap Singh
//
//  Created by Gurpartap Singh on 06/05/12.
//  Copyright (c) 2012 Gurpartap Singh. All rights reserved.
//

#import "NSData+Base64.h"

@implementation NSData (Base64Additions)

+ (NSData *)base64DataFromString:(NSString *)string {
  unsigned long ixtext, lentext;
  unsigned char ch, inbuf[4], outbuf[3];
  short i, ixinbuf;
  Boolean flignore, flendtext = false;
  const unsigned char *tempcstring;
  NSMutableData *theData;
  
  if (string == nil) {
    return [NSData data];
  }
  
  ixtext = 0;
  
  tempcstring = (const unsigned char *)[string UTF8String];
  
  lentext = [string length];
  
  theData = [NSMutableData dataWithCapacity: lentext];
  
  ixinbuf = 0;
  
  while (true) {
    if (ixtext >= lentext) {
      break;
    }
    
    ch = tempcstring [ixtext++];
    
    flignore = false;
    
    if ((ch >= 'A') && (ch <= 'Z')) {
      ch = ch - 'A';
    }
    else if ((ch >= 'a') && (ch <= 'z')) {
      ch = ch - 'a' + 26;
    }
    else if ((ch >= '0') && (ch <= '9')) {
      ch = ch - '0' + 52;
    }
    else if (ch == '+') {
      ch = 62;
    }
    else if (ch == '=') {
      flendtext = true;
    }
    else if (ch == '/') {
      ch = 63;
    }
    else {
      flignore = true; 
    }
    
    if (!flignore) {
      short ctcharsinbuf = 3;
      Boolean flbreak = false;
      
      if (flendtext) {
        if (ixinbuf == 0) {
          break;
        }
        
        if ((ixinbuf == 1) || (ixinbuf == 2)) {
          ctcharsinbuf = 1;
        }
        else {
          ctcharsinbuf = 2;
        }
        
        ixinbuf = 3;
        
        flbreak = true;
      }
      
      inbuf [ixinbuf++] = ch;
      
      if (ixinbuf == 4) {
        ixinbuf = 0;
        
        outbuf[0] = (inbuf[0] << 2) | ((inbuf[1] & 0x30) >> 4);
        outbuf[1] = ((inbuf[1] & 0x0F) << 4) | ((inbuf[2] & 0x3C) >> 2);
        outbuf[2] = ((inbuf[2] & 0x03) << 6) | (inbuf[3] & 0x3F);
        
        for (i = 0; i < ctcharsinbuf; i++) {
          [theData appendBytes: &outbuf[i] length: 1];
        }
      }
      
      if (flbreak) {
        break;
      }
    }
  }
  
  return theData;
}

@end

NSData+CommonCrypto.h

/*
 *  NSData+CommonCrypto.h
 *  AQToolkit
 *
 *  Created by Jim Dovey on 31/8/2008.
 *
 *  Copyright (c) 2008-2009, Jim Dovey
 *  All rights reserved.
 *  
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  Redistributions of source code must retain the above copyright notice,
 *  this list of conditions and the following disclaimer.
 *  
 *  Redistributions in binary form must reproduce the above copyright
 *  notice, this list of conditions and the following disclaimer in the
 *  documentation and/or other materials provided with the distribution.
 *  
 *  Neither the name of this project's author nor the names of its
 *  contributors may be used to endorse or promote products derived from
 *  this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *  HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 *  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#import <Foundation/NSData.h>
#import <Foundation/NSError.h>
#import <CommonCrypto/CommonCryptor.h>
#import <CommonCrypto/CommonHMAC.h>

extern NSString * const kCommonCryptoErrorDomain;

@interface NSError (CommonCryptoErrorDomain)
+ (NSError *) errorWithCCCryptorStatus: (CCCryptorStatus) status;
@end

@interface NSData (CommonDigest)

- (NSData *) MD2Sum;
- (NSData *) MD4Sum;
- (NSData *) MD5Sum;

- (NSData *) SHA1Hash;
- (NSData *) SHA224Hash;
- (NSData *) SHA256Hash;
- (NSData *) SHA384Hash;
- (NSData *) SHA512Hash;

@end

@interface NSData (CommonCryptor)

- (NSData *) AES256EncryptedDataUsingKey: (id) key error: (NSError **) error;
- (NSData *) decryptedAES256DataUsingKey: (id) key error: (NSError **) error;

- (NSData *) DESEncryptedDataUsingKey: (id) key error: (NSError **) error;
- (NSData *) decryptedDESDataUsingKey: (id) key error: (NSError **) error;

- (NSData *) CASTEncryptedDataUsingKey: (id) key error: (NSError **) error;
- (NSData *) decryptedCASTDataUsingKey: (id) key error: (NSError **) error;

@end

@interface NSData (LowLevelCommonCryptor)

- (NSData *) dataEncryptedUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key        // data or string
                                   error: (CCCryptorStatus *) error;
- (NSData *) dataEncryptedUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key        // data or string
                                 options: (CCOptions) options
                                   error: (CCCryptorStatus *) error;
- (NSData *) dataEncryptedUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key        // data or string
                    initializationVector: (id) iv        // data or string
                                 options: (CCOptions) options
                                   error: (CCCryptorStatus *) error;

- (NSData *) decryptedDataUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key        // data or string
                                   error: (CCCryptorStatus *) error;
- (NSData *) decryptedDataUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key        // data or string
                                 options: (CCOptions) options
                                   error: (CCCryptorStatus *) error;
- (NSData *) decryptedDataUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key        // data or string
                    initializationVector: (id) iv        // data or string
                                 options: (CCOptions) options
                                   error: (CCCryptorStatus *) error;

@end

@interface NSData (CommonHMAC)

- (NSData *) HMACWithAlgorithm: (CCHmacAlgorithm) algorithm;
- (NSData *) HMACWithAlgorithm: (CCHmacAlgorithm) algorithm key: (id) key;

@end

NSData+CommonCrypto.m

/*
 *  NSData+CommonCrypto.m
 *  AQToolkit
 *
 *  Created by Jim Dovey on 31/8/2008.
 *
 *  Copyright (c) 2008-2009, Jim Dovey
 *  All rights reserved.
 *  
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  Redistributions of source code must retain the above copyright notice,
 *  this list of conditions and the following disclaimer.
 *  
 *  Redistributions in binary form must reproduce the above copyright
 *  notice, this list of conditions and the following disclaimer in the
 *  documentation and/or other materials provided with the distribution.
 *  
 *  Neither the name of this project's author nor the names of its
 *  contributors may be used to endorse or promote products derived from
 *  this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *  HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 *  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#import <Foundation/Foundation.h>
#import "NSData+CommonCrypto.h"
#import <CommonCrypto/CommonDigest.h>
#import <CommonCrypto/CommonCryptor.h>
#import <CommonCrypto/CommonHMAC.h>

NSString * const kCommonCryptoErrorDomain = @"CommonCryptoErrorDomain";

@implementation NSError (CommonCryptoErrorDomain)

+ (NSError *) errorWithCCCryptorStatus: (CCCryptorStatus) status
{
    NSString * description = nil, * reason = nil;
    
    switch ( status )
    {
        case kCCSuccess:
            description = NSLocalizedString(@"Success", @"Error description");
            break;
            
        case kCCParamError:
            description = NSLocalizedString(@"Parameter Error", @"Error description");
            reason = NSLocalizedString(@"Illegal parameter supplied to encryption/decryption algorithm", @"Error reason");
            break;
            
        case kCCBufferTooSmall:
            description = NSLocalizedString(@"Buffer Too Small", @"Error description");
            reason = NSLocalizedString(@"Insufficient buffer provided for specified operation", @"Error reason");
            break;
            
        case kCCMemoryFailure:
            description = NSLocalizedString(@"Memory Failure", @"Error description");
            reason = NSLocalizedString(@"Failed to allocate memory", @"Error reason");
            break;
            
        case kCCAlignmentError:
            description = NSLocalizedString(@"Alignment Error", @"Error description");
            reason = NSLocalizedString(@"Input size to encryption algorithm was not aligned correctly", @"Error reason");
            break;
            
        case kCCDecodeError:
            description = NSLocalizedString(@"Decode Error", @"Error description");
            reason = NSLocalizedString(@"Input data did not decode or decrypt correctly", @"Error reason");
            break;
            
        case kCCUnimplemented:
            description = NSLocalizedString(@"Unimplemented Function", @"Error description");
            reason = NSLocalizedString(@"Function not implemented for the current algorithm", @"Error reason");
            break;
            
        default:
            description = NSLocalizedString(@"Unknown Error", @"Error description");
            break;
    }
    
    NSMutableDictionary * userInfo = [[NSMutableDictionary alloc] init];
    [userInfo setObject: description forKey: NSLocalizedDescriptionKey];
    
    if ( reason != nil )
        [userInfo setObject: reason forKey: NSLocalizedFailureReasonErrorKey];
    
    NSError * result = [NSError errorWithDomain: kCommonCryptoErrorDomain code: status userInfo: userInfo];
    #if !__has_feature(objc_arc)
        [userInfo release];
    #endif
    
    return ( result );
}

@end

#pragma mark -

@implementation NSData (CommonDigest)

- (NSData *) MD2Sum
{
    unsigned char hash[CC_MD2_DIGEST_LENGTH];
    (void) CC_MD2( [self bytes], (CC_LONG)[self length], hash );
    return ( [NSData dataWithBytes: hash length: CC_MD2_DIGEST_LENGTH] );
}

- (NSData *) MD4Sum
{
    unsigned char hash[CC_MD4_DIGEST_LENGTH];
    (void) CC_MD4( [self bytes], (CC_LONG)[self length], hash );
    return ( [NSData dataWithBytes: hash length: CC_MD4_DIGEST_LENGTH] );
}

- (NSData *) MD5Sum
{
    unsigned char hash[CC_MD5_DIGEST_LENGTH];
    (void) CC_MD5( [self bytes], (CC_LONG)[self length], hash );
    return ( [NSData dataWithBytes: hash length: CC_MD5_DIGEST_LENGTH] );
}

- (NSData *) SHA1Hash
{
    unsigned char hash[CC_SHA1_DIGEST_LENGTH];
    (void) CC_SHA1( [self bytes], (CC_LONG)[self length], hash );
    return ( [NSData dataWithBytes: hash length: CC_SHA1_DIGEST_LENGTH] );
}

- (NSData *) SHA224Hash
{
    unsigned char hash[CC_SHA224_DIGEST_LENGTH];
    (void) CC_SHA224( [self bytes], (CC_LONG)[self length], hash );
    return ( [NSData dataWithBytes: hash length: CC_SHA224_DIGEST_LENGTH] );
}

- (NSData *) SHA256Hash
{
    unsigned char hash[CC_SHA256_DIGEST_LENGTH];
    (void) CC_SHA256( [self bytes], (CC_LONG)[self length], hash );
    return ( [NSData dataWithBytes: hash length: CC_SHA256_DIGEST_LENGTH] );
}

- (NSData *) SHA384Hash
{
    unsigned char hash[CC_SHA384_DIGEST_LENGTH];
    (void) CC_SHA384( [self bytes], (CC_LONG)[self length], hash );
    return ( [NSData dataWithBytes: hash length: CC_SHA384_DIGEST_LENGTH] );
}

- (NSData *) SHA512Hash
{
    unsigned char hash[CC_SHA512_DIGEST_LENGTH];
    (void) CC_SHA512( [self bytes], (CC_LONG)[self length], hash );
    return ( [NSData dataWithBytes: hash length: CC_SHA512_DIGEST_LENGTH] );
}

@end

@implementation NSData (CommonCryptor)

- (NSData *) AES256EncryptedDataUsingKey: (id) key error: (NSError **) error
{
    CCCryptorStatus status = kCCSuccess;
    NSData * result = [self dataEncryptedUsingAlgorithm: kCCAlgorithmAES128
                                                  key: key
                                              options: kCCOptionPKCS7Padding
                                                error: &status];
    
    if ( result != nil )
        return ( result );
    
    if ( error != NULL )
        *error = [NSError errorWithCCCryptorStatus: status];
    
    return ( nil );
}

- (NSData *) decryptedAES256DataUsingKey: (id) key error: (NSError **) error
{
    CCCryptorStatus status = kCCSuccess;
    NSData * result = [self decryptedDataUsingAlgorithm: kCCAlgorithmAES128
                                                  key: key
                                              options: kCCOptionPKCS7Padding
                                                error: &status];
    
    if ( result != nil )
        return ( result );
    
    if ( error != NULL )
        *error = [NSError errorWithCCCryptorStatus: status];
    
    return ( nil );
}

- (NSData *) DESEncryptedDataUsingKey: (id) key error: (NSError **) error
{
    CCCryptorStatus status = kCCSuccess;
    NSData * result = [self dataEncryptedUsingAlgorithm: kCCAlgorithmDES
                                                  key: key
                                              options: kCCOptionPKCS7Padding
                                                error: &status];
    
    if ( result != nil )
        return ( result );
    
    if ( error != NULL )
        *error = [NSError errorWithCCCryptorStatus: status];
    
    return ( nil );
}

- (NSData *) decryptedDESDataUsingKey: (id) key error: (NSError **) error
{
    CCCryptorStatus status = kCCSuccess;
    NSData * result = [self decryptedDataUsingAlgorithm: kCCAlgorithmDES
                                                  key: key
                                              options: kCCOptionPKCS7Padding
                                                error: &status];
    
    if ( result != nil )
        return ( result );
    
    if ( error != NULL )
        *error = [NSError errorWithCCCryptorStatus: status];
    
    return ( nil );
}

- (NSData *) CASTEncryptedDataUsingKey: (id) key error: (NSError **) error
{
    CCCryptorStatus status = kCCSuccess;
    NSData * result = [self dataEncryptedUsingAlgorithm: kCCAlgorithmCAST
                                                  key: key
                                              options: kCCOptionPKCS7Padding
                                                error: &status];
    
    if ( result != nil )
        return ( result );
    
    if ( error != NULL )
        *error = [NSError errorWithCCCryptorStatus: status];
    
    return ( nil );
}

- (NSData *) decryptedCASTDataUsingKey: (id) key error: (NSError **) error
{
    CCCryptorStatus status = kCCSuccess;
    NSData * result = [self decryptedDataUsingAlgorithm: kCCAlgorithmCAST
                                                  key: key
                                              options: kCCOptionPKCS7Padding
                                                error: &status];
    
    if ( result != nil )
        return ( result );
    
    if ( error != NULL )
        *error = [NSError errorWithCCCryptorStatus: status];
    
    return ( nil );
}

@end

static void FixKeyLengths( CCAlgorithm algorithm, NSMutableData * keyData, NSMutableData * ivData )
{
    NSUInteger keyLength = [keyData length];
    switch ( algorithm )
    {
        case kCCAlgorithmAES128:
        {
            if ( keyLength < 16 )
            {
                [keyData setLength: 16];
            }
            else if ( keyLength < 24 )
            {
                [keyData setLength: 24];
            }
            else
            {
                [keyData setLength: 32];
            }
            
            break;
        }
            
        case kCCAlgorithmDES:
        {
            [keyData setLength: 8];
            break;
        }
            
        case kCCAlgorithm3DES:
        {
            [keyData setLength: 24];
            break;
        }
            
        case kCCAlgorithmCAST:
        {
            if ( keyLength < 5 )
            {
                [keyData setLength: 5];
            }
            else if ( keyLength > 16 )
            {
                [keyData setLength: 16];
            }
            
            break;
        }
            
        case kCCAlgorithmRC4:
        {
            if ( keyLength > 512 )
                [keyData setLength: 512];
            break;
        }
            
        default:
            break;
    }
    
    [ivData setLength: [keyData length]];
}

@implementation NSData (LowLevelCommonCryptor)

- (NSData *) _runCryptor: (CCCryptorRef) cryptor result: (CCCryptorStatus *) status
{
    size_t bufsize = CCCryptorGetOutputLength( cryptor, (size_t)[self length], true );
    void * buf = malloc( bufsize );
    size_t bufused = 0;
  size_t bytesTotal = 0;
    *status = CCCryptorUpdate( cryptor, [self bytes], (size_t)[self length], 
                            buf, bufsize, &bufused );
    if ( *status != kCCSuccess )
    {
        free( buf );
        return ( nil );
    }
  
  bytesTotal += bufused;
    
    // From Brent Royal-Gordon (Twitter: architechies):
    //  Need to update buf ptr past used bytes when calling CCCryptorFinal()
    *status = CCCryptorFinal( cryptor, buf + bufused, bufsize - bufused, &bufused );
    if ( *status != kCCSuccess )
    {
        free( buf );
        return ( nil );
    }
  
  bytesTotal += bufused;
    
    return ( [NSData dataWithBytesNoCopy: buf length: bytesTotal] );
}

- (NSData *) dataEncryptedUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key
                                   error: (CCCryptorStatus *) error
{
    return ( [self dataEncryptedUsingAlgorithm: algorithm
                                         key: key
                        initializationVector: nil
                                     options: 0
                                       error: error] );
}

- (NSData *) dataEncryptedUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key
                                 options: (CCOptions) options
                                   error: (CCCryptorStatus *) error
{
  return ( [self dataEncryptedUsingAlgorithm: algorithm
                                         key: key
                        initializationVector: nil
                                     options: options
                                       error: error] );
}

- (NSData *) dataEncryptedUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key
                    initializationVector: (id) iv
                                 options: (CCOptions) options
                                   error: (CCCryptorStatus *) error
{
    CCCryptorRef cryptor = NULL;
    CCCryptorStatus status = kCCSuccess;
    
    NSParameterAssert([key isKindOfClass: [NSData class]] || [key isKindOfClass: [NSString class]]);
    NSParameterAssert(iv == nil || [iv isKindOfClass: [NSData class]] || [iv isKindOfClass: [NSString class]]);
    
    NSMutableData * keyData, * ivData;
    if ( [key isKindOfClass: [NSData class]] )
        keyData = (NSMutableData *) [key mutableCopy];
    else
        keyData = [[key dataUsingEncoding: NSUTF8StringEncoding] mutableCopy];
    
    if ( [iv isKindOfClass: [NSString class]] )
        ivData = [[iv dataUsingEncoding: NSUTF8StringEncoding] mutableCopy];
    else
        ivData = (NSMutableData *) [iv mutableCopy];    // data or nil
    
    #if !__has_feature(objc_arc)
        [keyData autorelease];
        [ivData autorelease];
    #endif
    // ensure correct lengths for key and iv data, based on algorithms
    FixKeyLengths( algorithm, keyData, ivData );
    
    status = CCCryptorCreate( kCCEncrypt, algorithm, options,
                           [keyData bytes], [keyData length], [ivData bytes],
                           &cryptor );
    
    if ( status != kCCSuccess )
    {
        if ( error != NULL )
            *error = status;
        return ( nil );
    }
    
    NSData * result = [self _runCryptor: cryptor result: &status];
    if ( (result == nil) && (error != NULL) )
        *error = status;
    
    CCCryptorRelease( cryptor );
    
    return ( result );
}

- (NSData *) decryptedDataUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key        // data or string
                                   error: (CCCryptorStatus *) error
{
    return ( [self decryptedDataUsingAlgorithm: algorithm
                                         key: key
                        initializationVector: nil
                                     options: 0
                                       error: error] );
}

- (NSData *) decryptedDataUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key        // data or string
                                 options: (CCOptions) options
                                   error: (CCCryptorStatus *) error
{
  return ( [self decryptedDataUsingAlgorithm: algorithm
                                         key: key
                        initializationVector: nil
                                     options: options
                                       error: error] );
}

- (NSData *) decryptedDataUsingAlgorithm: (CCAlgorithm) algorithm
                                     key: (id) key        // data or string
                    initializationVector: (id) iv        // data or string
                                 options: (CCOptions) options
                                   error: (CCCryptorStatus *) error
{
    CCCryptorRef cryptor = NULL;
    CCCryptorStatus status = kCCSuccess;
    
    NSParameterAssert([key isKindOfClass: [NSData class]] || [key isKindOfClass: [NSString class]]);
    NSParameterAssert(iv == nil || [iv isKindOfClass: [NSData class]] || [iv isKindOfClass: [NSString class]]);
    
    NSMutableData * keyData, * ivData;
    if ( [key isKindOfClass: [NSData class]] )
        keyData = (NSMutableData *) [key mutableCopy];
    else
        keyData = [[key dataUsingEncoding: NSUTF8StringEncoding] mutableCopy];
    
    if ( [iv isKindOfClass: [NSString class]] )
        ivData = [[iv dataUsingEncoding: NSUTF8StringEncoding] mutableCopy];
    else
        ivData = (NSMutableData *) [iv mutableCopy];    // data or nil
    
    #if !__has_feature(objc_arc)
        [keyData autorelease];
        [ivData autorelease];
    #endif
    
    // ensure correct lengths for key and iv data, based on algorithms
    FixKeyLengths( algorithm, keyData, ivData );
    
    status = CCCryptorCreate( kCCDecrypt, algorithm, options,
                           [keyData bytes], [keyData length], [ivData bytes],
                           &cryptor );
    
    if ( status != kCCSuccess )
    {
        if ( error != NULL )
            *error = status;
        return ( nil );
    }
    
    NSData * result = [self _runCryptor: cryptor result: &status];
    if ( (result == nil) && (error != NULL) )
        *error = status;
    
    CCCryptorRelease( cryptor );
    
    return ( result );
}

@end

@implementation NSData (CommonHMAC)

- (NSData *) HMACWithAlgorithm: (CCHmacAlgorithm) algorithm
{
    return ( [self HMACWithAlgorithm: algorithm key: nil] );
}

- (NSData *) HMACWithAlgorithm: (CCHmacAlgorithm) algorithm key: (id) key
{
    NSParameterAssert(key == nil || [key isKindOfClass: [NSData class]] || [key isKindOfClass: [NSString class]]);
    
    NSData * keyData = nil;
    if ( [key isKindOfClass: [NSString class]] )
        keyData = [key dataUsingEncoding: NSUTF8StringEncoding];
    else
        keyData = (NSData *) key;
    
    // this could be either CC_SHA1_DIGEST_LENGTH or CC_MD5_DIGEST_LENGTH. SHA1 is larger.
    unsigned char buf[CC_SHA1_DIGEST_LENGTH];
    CCHmac( algorithm, [keyData bytes], [keyData length], [self bytes], [self length], buf );
    
    return ( [NSData dataWithBytes: buf length: (algorithm == kCCHmacAlgMD5 ? CC_MD5_DIGEST_LENGTH : CC_SHA1_DIGEST_LENGTH)] );
}

@end

NSString+Base64.h

//
//  NSString+Base64.h
//  Gurpartap Singh
//
//  Created by Gurpartap Singh on 06/05/12.
//  Copyright (c) 2012 Gurpartap Singh. All rights reserved.
//

#import <Foundation/NSString.h>

@interface NSString (Base64Additions)

+ (NSString *)base64StringFromData:(NSData *)data length:(NSUInteger)length;

@end

NSString+Base64.m

//
//  NSStringAdditions.m
//  Gurpartap Singh
//
//  Created by Gurpartap Singh on 06/05/12.
//  Copyright (c) 2012 Gurpartap Singh. All rights reserved.
//

#import "NSString+Base64.h"

static char base64EncodingTable[64] = {
  'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
  'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
  'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
  'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
};

@implementation NSString (Base64Additions)

+ (NSString *)base64StringFromData: (NSData *)data length: (NSUInteger)length {
  unsigned long ixtext, lentext;
  long ctremaining;
  unsigned char input[3], output[4];
  short i, charsonline = 0, ctcopy;
  const unsigned char *raw;
  NSMutableString *result;
  
  lentext = [data length]; 
  if (lentext < 1) {
    return @"";
  }
  result = [NSMutableString stringWithCapacity: lentext];
  raw = [data bytes];
  ixtext = 0; 
  
  while (true) {
    ctremaining = lentext - ixtext;
    if (ctremaining <= 0) {
      break;
    }
    for (i = 0; i < 3; i++) { 
      unsigned long ix = ixtext + i;
      if (ix < lentext) {
        input[i] = raw[ix];
      }
      else {
        input[i] = 0;
      }
    }
    output[0] = (input[0] & 0xFC) >> 2;
    output[1] = ((input[0] & 0x03) << 4) | ((input[1] & 0xF0) >> 4);
    output[2] = ((input[1] & 0x0F) << 2) | ((input[2] & 0xC0) >> 6);
    output[3] = input[2] & 0x3F;
    ctcopy = 4;
    switch (ctremaining) {
      case 1: 
        ctcopy = 2; 
        break;
      case 2: 
        ctcopy = 3; 
        break;
    }
    
    for (i = 0; i < ctcopy; i++) {
      [result appendString: [NSString stringWithFormat: @"%c", base64EncodingTable[output[i]]]];
    }
    
    for (i = ctcopy; i < 4; i++) {
      [result appendString: @"="];
    }
    
    ixtext += 3;
    charsonline += 4;
    
    if ((length > 0) && (charsonline >= length)) {
      charsonline = 0;
    }
  }     
  return result;
}

@end

转载于:https://www.cnblogs.com/pengyingh/articles/4788851.html