├── RSAEncryptor.h
└── RSAEncryptor.m


/RSAEncryptor.h:
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 1 | 
 2 | 
 3 | // http://www.cnblogs.com/makemelike/articles/3802518.html
 4 | 
 5 | 
 6 | 
 7 | #import <Foundation/Foundation.h>
 8 | 
 9 | @interface RSAEncryptor : NSObject
10 | 
11 | #pragma mark - Instance Methods
12 | - (void) loadPublicKeyFromFile: (NSString*) derFilePath;
13 | - (void) loadPublicKeyFromData: (NSData*) derData;
14 | 
15 | - (void) loadPrivateKeyFromFile: (NSString*) p12FilePath password:(NSString*)p12Password;
16 | - (void) loadPrivateKeyFromData: (NSData*) p12Data password:(NSString*)p12Password;
17 | 
18 | - (NSString*) rsaEncryptString:(NSString*)string;
19 | - (NSData*) rsaEncryptData:(NSData*)data ;
20 | 
21 | - (NSString*) rsaDecryptString:(NSString*)string;
22 | - (NSData*) rsaDecryptData:(NSData*)data;
23 | 
24 | #pragma mark - Class Methods
25 | + (void) setSharedInstance: (RSAEncryptor*)instance;
26 | + (RSAEncryptor*) sharedInstance;
27 | 
28 | @end


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/RSAEncryptor.m:
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  1 | 
  2 | // http://www.cnblogs.com/makemelike/articles/3802518.html
  3 | 
  4 | #import "RSAEncryptor.h"
  5 | #import <Security/Security.h>
  6 | 
  7 | 
  8 | @implementation RSAEncryptor{
  9 |     SecKeyRef publicKey;
 10 |     SecKeyRef privateKey;
 11 | }
 12 | - (void)dealloc{
 13 |     CFRelease(publicKey);
 14 |     CFRelease(privateKey);
 15 | }
 16 | - (SecKeyRef)getPublicKey {
 17 |     return publicKey;
 18 | }
 19 | - (SecKeyRef)getPrivateKey {
 20 |     return privateKey;
 21 | }
 22 | - (void)loadPublicKeyFromFile: (NSString*) derFilePath{
 23 |     NSData *derData = [[NSData alloc] initWithContentsOfFile:derFilePath];
 24 |     [self loadPublicKeyFromData: derData];
 25 | }
 26 | - (void)loadPublicKeyFromData: (NSData*) derData{
 27 |     publicKey = [self getPublicKeyRefrenceFromeData: derData];
 28 | }
 29 | - (void)loadPrivateKeyFromFile: (NSString*) p12FilePath password:(NSString*)p12Password{
 30 |     NSData *p12Data = [NSData dataWithContentsOfFile:p12FilePath];
 31 |     [self loadPrivateKeyFromData: p12Data password:p12Password];
 32 | }
 33 | - (void)loadPrivateKeyFromData: (NSData*) p12Data password:(NSString*)p12Password{
 34 |     privateKey = [self getPrivateKeyRefrenceFromData: p12Data password: p12Password];
 35 | }
 36 | 
 37 | #pragma mark - Private Methods
 38 | - (SecKeyRef) getPublicKeyRefrenceFromeData: (NSData*)derData{
 39 |     SecCertificateRef myCertificate = SecCertificateCreateWithData(kCFAllocatorDefault, (__bridge CFDataRef)derData);
 40 |     SecPolicyRef myPolicy = SecPolicyCreateBasicX509();
 41 |     SecTrustRef myTrust;
 42 |     OSStatus status = SecTrustCreateWithCertificates(myCertificate,myPolicy,&myTrust);
 43 |     SecTrustResultType trustResult;
 44 |     if (status == noErr) {
 45 |         status = SecTrustEvaluate(myTrust, &trustResult);
 46 |     }
 47 |     SecKeyRef securityKey = SecTrustCopyPublicKey(myTrust);
 48 |     CFRelease(myCertificate);
 49 |     CFRelease(myPolicy);
 50 |     CFRelease(myTrust);
 51 |     
 52 |     return securityKey;
 53 | }
 54 | - (SecKeyRef) getPrivateKeyRefrenceFromData: (NSData*)p12Data password:(NSString*)password{
 55 |     SecKeyRef privateKeyRef = NULL;
 56 |     NSMutableDictionary * options = [[NSMutableDictionary alloc] init];
 57 |     [options setObject: password forKey:(__bridge id)kSecImportExportPassphrase];
 58 |     CFArrayRef items = CFArrayCreate(NULL, 0, 0, NULL);
 59 |     OSStatus securityError = SecPKCS12Import((__bridge CFDataRef) p12Data, (__bridge CFDictionaryRef)options, &items);
 60 |     if (securityError == noErr && CFArrayGetCount(items) > 0) {
 61 |         CFDictionaryRef identityDict = CFArrayGetValueAtIndex(items, 0);
 62 |         SecIdentityRef identityApp = (SecIdentityRef)CFDictionaryGetValue(identityDict, kSecImportItemIdentity);
 63 |         securityError = SecIdentityCopyPrivateKey(identityApp, &privateKeyRef);
 64 |         if (securityError != noErr) {
 65 |             privateKeyRef = NULL;
 66 |         }
 67 |     }
 68 |     CFRelease(items);
 69 |     
 70 |     return privateKeyRef;
 71 | }
 72 | #pragma mark - Encrypt
 73 | - (NSString*) rsaEncryptString:(NSString*)string {
 74 |     NSData* data = [string dataUsingEncoding:NSUTF8StringEncoding];
 75 |     NSData* encryptedData = [self rsaEncryptData: data];
 76 |     NSString* base64EncryptedString = [encryptedData base64EncodedStringWithOptions:NSDataBase64EncodingEndLineWithLineFeed];
 77 |     return base64EncryptedString;
 78 | }
 79 | 
 80 | // 加密的大小受限于SecKeyEncrypt函数，SecKeyEncrypt要求明文和密钥的长度一致，如果要加密更长的内容，需要把内容按密钥长度分成多份，然后多次调用SecKeyEncrypt来实现
 81 | - (NSData*) rsaEncryptData:(NSData*)data {
 82 |     SecKeyRef key = [self getPublicKey];
 83 |     size_t cipherBufferSize = SecKeyGetBlockSize(key);
 84 |     uint8_t *cipherBuffer = malloc(cipherBufferSize * sizeof(uint8_t));
 85 |     size_t blockSize = cipherBufferSize - 11;       // 分段加密
 86 |     size_t blockCount = (size_t)ceil([data length] / (double)blockSize);
 87 |     NSMutableData *encryptedData = [[NSMutableData alloc] init] ;
 88 |     for (int i=0; i<blockCount; i++) {
 89 |         NSInteger bufferSize = MIN(blockSize,[data length] - i * blockSize);
 90 |         NSData *buffer = [data subdataWithRange:NSMakeRange(i * blockSize, bufferSize)];
 91 |         OSStatus status = SecKeyEncrypt(key, kSecPaddingPKCS1, (const uint8_t *)[buffer bytes], [buffer length], cipherBuffer, &cipherBufferSize);
 92 |         if (status == noErr){
 93 |             NSData *encryptedBytes = [[NSData alloc] initWithBytes:(const void *)cipherBuffer length:cipherBufferSize];
 94 |             [encryptedData appendData:encryptedBytes];
 95 |         }else{
 96 |             if (cipherBuffer) {
 97 |                 free(cipherBuffer);
 98 |             }
 99 |             return nil;
100 |         }
101 |     }
102 |     if (cipherBuffer){
103 |         free(cipherBuffer);
104 |     }
105 |     return encryptedData;
106 | }
107 | 
108 | #pragma mark - Decrypt
109 | - (NSString*) rsaDecryptString:(NSString*)string {
110 |     NSData* data = [[NSData alloc] initWithBase64EncodedString:string options:0];
111 |     NSData* decryptData = [self rsaDecryptData: data];
112 |     NSString* result = [[NSString alloc] initWithData: decryptData encoding:NSUTF8StringEncoding];
113 |     return result;
114 | }
115 | - (NSData*) rsaDecryptData:(NSData*)data {
116 |     SecKeyRef key = [self getPrivateKey];
117 |     size_t cipherLen = [data length];
118 |     void *cipher = malloc(cipherLen);
119 |     [data getBytes:cipher length:cipherLen];
120 |     size_t plainLen = SecKeyGetBlockSize(key) - 12;
121 |     void *plain = malloc(plainLen);
122 |     OSStatus status = SecKeyDecrypt(key, kSecPaddingPKCS1, cipher, cipherLen, plain, &plainLen);
123 |     
124 |     if (status != noErr) {
125 |         return nil;
126 |     }
127 |     
128 |     NSData *decryptedData = [[NSData alloc] initWithBytes:(const void *)plain length:plainLen];
129 |     
130 |     return decryptedData;
131 | }
132 | 
133 | #pragma mark - Class Methods
134 | static RSAEncryptor* sharedInstance = nil;
135 | + (void) setSharedInstance: (RSAEncryptor*)instance{
136 |     sharedInstance = instance;
137 | }
138 | + (RSAEncryptor*) sharedInstance{
139 |     return sharedInstance;
140 | }
141 | 
142 | 
143 | @end
144 | 
145 | 


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