iOS常用的加密模式
来源:互联网 发布:数据库置疑修复 编辑:程序博客网 时间:2024/04/30 02:24
之前的项目中接触过一些加密的方法,也没有太仔细的进行记录和研究。最近在写SDK
时,加密模块的占比相当之大;借此时机,对我们常用的加密方式做一个笔记。
为什么要做加密操作?
加密就是为了保证我们的数据安全,即不被他人篡改或截取到有用的信息的操作。iOS
一直以安全著称,但是从Xcode
的Ghost
事件之后,iOS
安全不可摧的神话似乎已经被打破。事实证明,无论是Android
还是iOS
,该加密处理的还是需要加密处理,谁也不能保证自己一定是安全的。下面我们来介绍iOS
常用到的加密方式。
iOS常用加密方式
常见的iOS代码加密常用加密方式包括Base64加密
、MD5加密
、AES加密
、RSA加密
等。无论选择哪种加密算法,最终都是为了保证代码安全,捍卫自己的产品原创性。
Base64加密
Base64
编码的思想是:采用64
个基本的ASCII码
字符对数据进行重新编码。它将需要编码的数据拆分成字节数组,以3
个字节为一组,按顺序排列24
位数据,再把这24
位数据分成4
组,即每组6
位;再在每组的的最高位前补两个0
凑足一个字节,这样就把一个3
字节为一组的数据重新编码成了4
个字节;当所要编码的数据的字节数不是3
的整倍数,也就是说在分组时最后一组不够3
个字节,这时在最后一组填充1
到2
个0
字节,并在最后编码完成后在结尾添加1
到2
个=
号。例如:将对ABC
进行Base64
编码首先取ABC
对应的ASCII码
值,A : 65
、B : 66
、C : 67
,再取二进制值A : 01000001
、B : 01000010
、C : 01000011
,然后把这三个字节的二进制码接起来010000010100001001000011
,再以6
位为单位分成4
个数据块并在最高位填充两个0
后形成4
个字节的编码后的值00010000
、00010100
、00001001
、00000011
;再把这4
个字节数据转化成10进制数
得16
、20
、19
、3
;最后根据Base64
给出的64
个基本字符表,查出对应的ASCII码
字符Q
、U
、J
、D
,这里的值实际就是数据在字符表中的索引。解码过程就是把4
个字节再还原成3
个字节再根据不同的数据形式把字节数组重新整理成数据。注:Base64字符表,包括大写A-Z
小写a-z
数字0-9
和+
以及/
。
Base64加密原则:6bit(原8bit)一个字节,不足的位数用0补齐,两个0用一个=表示。
Base64加密特点:
- 数据加密之后,数据量会变大,变大1/3左右。- 可进行反向解密。- 编码后有个非常显著的特点,末尾有个=号。
在iOS中Base64加解密使用方法介绍(本例使用系统API,仅支持iOS7及以后的系统版本)
/****************************Base64.m类实现文件内容****************************/+ (NSString *)base64EncodedStringWithData:(NSData *)data{ //判断是否传入需要加密数据参数 if ((data == nil) || (data == NULL)) { return nil; } else if (![data isKindOfClass:[NSData class]]) { return nil; } //判断设备系统是否满足条件 if ([[[UIDevice currentDevice] systemVersion] doubleValue] <= 6.9) { return nil; } //使用系统的API进行Base64加密操作 NSDataBase64EncodingOptions options; options = NSDataBase64EncodingEndLineWithLineFeed; return [data base64EncodedStringWithOptions:options];}+ (NSData *)base64DecodeDataWithString:(NSString *)string{ //判断是否传入需要加密数据参数 if ((string == nil) || (string == NULL)) { return nil; } else if (![string isKindOfClass:[NSString class]]) { return nil; } //判断设备系统是否满足条件 if ([[[UIDevice currentDevice] systemVersion] doubleValue] <= 6.9) { return nil; } //使用系统的API进行Base64解密操作 NSDataBase64DecodingOptions options; options = NSDataBase64DecodingIgnoreUnknownCharacters; return [[NSData alloc] initWithBase64EncodedString:string options:options];}/*****************************************************************************///使用Base64文件进行Base64加密和解密/*********************************使用Base64类*********************************///使用Base64执行加密操作NSString *string = @"abcdefghijklmnopqrstuvwxyz";NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];NSString *encodeString = [Base64 base64EncodedStringWithData:data];NSLog(@"encodeString : %@", encodeString);//使用Base64执行解密操作NSString *decodeString = nil;NSData *decodeData = [Base64 base64DecodeDataWithString:encodeString];decodeString = [[NSString alloc] initWithData:decodeData encoding:NSUTF8StringEncoding];NSLog(@"decodeString : %@", decodeString);/******************************************************************************/
MD5加密(MD5是一种摘要,而非加密,只是经常与加密配合使用)
MD5
的全称是Message-DigestAlgorithm 5
,Message-Digest
泛指字节串(Message
)的Hash
变换,就是把一个任意长度的字节串
变换成一定长的大整数。请注意我使用了字节串
而不是字符串
这个词,是因为这种变换只与字节的值有关,与字符集或编码方式无关。MD5
将任意长度的字节串
变换成一个128bit
的大整数,并且它是一个不可逆的字符串变换算法,换句话说就是,即使你看到源程序和算法描述,也无法将一个MD5
的值变换回原始的字符串,从数学原理上说,是因为原始的字符串有无穷多个,这有点象不存在反函数的数学函数。MD5
的典型应用是对一段Message
(字节串)产生fingerprint
(指纹),以防止被”篡改”。举个例子,你将一段话写在一个叫readme.txt
文件中,并对这个readme.txt
产生一个MD5
的值并记录在案,然后你可以传播这个文件给别人,别人如果修改了文件中的任何内容,你对这个文件重新计算MD5
时就会发现。如果再有一个第三方的认证机构,用MD5
还可以防止文件作者的”抵赖”,这就是所谓的数字签名应用。MD5
还广泛用于加密和解密技术上,在很多操作系统中,用户的密码是以MD5
值(或类似的其它算法)的方式保存的,用户Login
的时候,系统是把用户输入的密码计算成MD5
值,然后再去和系统中保存的MD5
值进行比较,而系统并”不知道”用户的密码是什么。MD5加密大体都应用在:验证数据或文件一致性、数字签名、安全访问认证等等。大概可比喻为:人的指纹来理解。
注:MD5
加密是不可逆的,也就是说,MD5
加密后是不能解密的,所谓的解密只是用大数据的”试用”,来测出结果的。
MD5特点:
- 压缩性 : 任意长度的数据,算出的MD5值长度都是固定的。- 容易计算 : 从原数据计算出MD5值很容易。- 抗修改性 : 对原数据进行任何改动,哪怕只修改一个字节,所得到的MD5值都有很大区别。- 弱抗碰撞 : 已知原数据和其MD5值,想找到一个具有相同MD5值的数据(即伪造数据)是非常困难的。- 强抗碰撞 : 想找到两个不同数据,使他们具有相同的MD5值,是非常困难的。
在iOS中MD5加密和验签使用方法介绍
/****************************MD5.m类实现文件内容****************************///对字符串数据进行MD5的签名+ (NSString *)md5SignWithString:(NSString *)string{ const char *object = [string UTF8String]; unsigned char result[CC_MD5_DIGEST_LENGTH]; CC_MD5(object,(CC_LONG)strlen(object),result); NSMutableString *hash = [NSMutableString string]; for (int i = 0; i < 16; i ++) { [hash appendFormat:@"%02X", result[i]]; } return [hash lowercaseString];}//对二进制数据进行MD5的签名+ (NSData *)md5SignWithData:(NSData *)data{ Byte byte[CC_MD5_DIGEST_LENGTH]; //定义一个字节数组来接收结果 CC_MD5((const void*)([data bytes]), (CC_LONG)[data length], byte); return [NSData dataWithBytes:byte length:CC_MD5_DIGEST_LENGTH];}/******************************************************************************///使用MD5文件进行MD5加密和验签/*********************************使用MD5类*********************************///使用MD5执行加密操作NSString *string2 = @"abcdefghijklmnopqrstuvwxyz";NSString *encodeString2 = [MD5 md5SignWithString:string2];NSLog(@"encodeString2 : %@", encodeString2);//MD5为不可逆的操作,使用MD5执行验签操作NSString *verifyString2 = [MD5 md5SignWithString:string2];NSLog(@"verifyString2 : %@", verifyString2);if ([verifyString2 isEqualToString:encodeString2]) { NSLog(@"md5 verify sign success");} else { NSLog(@"md5 verify sign failed");}/******************************************************************************/
AES加密
高级加密标准Advanced Encryption Standard
简称:AES
,在密码学中又称Rijndael加密法
,是美国联邦政府采用的一种区块加密标准。它是一种对称加密算法,这个标准也替代原先的DES标准,已经被多方分析且广为全世界所使用。AES设计有三个密钥长度:128、192、256位,相对而言,AES的128密钥比DES的56密钥强1021倍。AES算法主要包括三个方面:轮变化、圈数和密钥扩展。总体来说,AES作为新一代的数据加密标准汇聚了强安全性、高性能、高效率、易用和灵活,在软件及硬件上都能快速地加解密且只需要很少的存储资源等优点。
AES加密流程介绍无从下笔,直接上图了。
AES加解密特点:
- AES强安全性、高性能、高效率、易用和灵活。- 在软件及硬件上都能快速地加解密且只需要很少的存储资源。
在iOS中AES加解密的实现介绍
//需要导入:#import <CommonCrypto/CommonCrypto.h>库才能使用/** * AES128 + ECB + PKCS7 * @param data 要加密的原始数据 * @param key 加密 key * @return 加密后数据 */+ (NSData *)encryptData:(NSData *)data key:(NSData *)key{ //判断解密的流数据是否存在 if ((data == nil) || (data == NULL)) { return nil; } else if (![data isKindOfClass:[NSData class]]) { return nil; } else if ([data length] <= 0) { return nil; } //判断解密的Key是否存在 if ((key == nil) || (key == NULL)) { return nil; } else if (![key isKindOfClass:[NSData class]]) { return nil; } else if ([key length] <= 0) { return nil; } //setup key NSData *result = nil; unsigned char cKey[kCCKeySizeAES128]; bzero(cKey, sizeof(cKey)); [key getBytes:cKey length:kCCKeySizeAES128]; //setup output buffer size_t bufferSize = [data length] + kCCBlockSizeAES128; void *buffer = malloc(bufferSize); //do encrypt size_t encryptedSize = 0; CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128, kCCOptionECBMode|kCCOptionPKCS7Padding, cKey, kCCKeySizeAES128, nil, [data bytes], [data length], buffer, bufferSize, &encryptedSize); if (cryptStatus == kCCSuccess) { result = [NSData dataWithBytesNoCopy:buffer length:encryptedSize]; } else { free(buffer); } return result;}/** * AES128 + ECB + PKCS7 * @param data 要解密的原始数据 * @param key 解密 key * @return 解密后数据 */+ (NSData *)decryptData:(NSData *)data key:(NSData *)key{ //判断解密的流数据是否存在 if ((data == nil) || (data == NULL)) { return nil; } else if (![data isKindOfClass:[NSData class]]) { return nil; } else if ([data length] <= 0) { return nil; } //判断解密的Key是否存在 if ((key == nil) || (key == NULL)) { return nil; } else if (![key isKindOfClass:[NSData class]]) { return nil; } else if ([key length] <= 0) { return nil; } //setup key NSData *result = nil; unsigned char cKey[kCCKeySizeAES128]; bzero(cKey, sizeof(cKey)); [key getBytes:cKey length:kCCKeySizeAES128]; //setup output buffer size_t bufferSize = [data length] + kCCBlockSizeAES128; void *buffer = malloc(bufferSize); //do decrypt size_t decryptedSize = 0; CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmAES128, kCCOptionECBMode|kCCOptionPKCS7Padding, cKey, kCCKeySizeAES128, nil, [data bytes], [data length], buffer, bufferSize, &decryptedSize); if (cryptStatus == kCCSuccess) { result = [NSData dataWithBytesNoCopy:buffer length:decryptedSize]; } else { free(buffer); } return result;}
在iOS中AES加解密使用方法介绍
//使用AES执行加密操作NSString *aesKey = @"a1b2c3d4e5f6g7h8";NSString *string3 = @"abcdefghijklmnopqrstuvwxyz";NSData *keyData3 = [aesKey dataUsingEncoding:NSUTF8StringEncoding];NSData *sourceData3 = [string3 dataUsingEncoding:NSUTF8StringEncoding];NSData *encodeData3 = [AESEncrypt encryptData:sourceData3 key:keyData3];NSLog(@"encodeData3 : %@", encodeData3);//使用AES执行解密操作NSString *decodeString3 = nil;NSData *decodeData3 = [AESEncrypt decryptData:encodeData3 key:keyData3];decodeString3 = [[NSString alloc] initWithData:decodeData3 encoding:NSUTF8StringEncoding];NSLog(@"decodeString3 : %@", decodeString3);
RSA加密
RSA是目前最有影响力的公钥加密算法,它能够抵抗到目前为止已知的绝大多数密码攻击,已被ISO推荐为公钥数据加密标准。RSA的公开密钥密码体制就是使用不同的加密密钥与解密密钥,是一种“由已知加密密钥推导出解密密钥在计算上是不可行的”密码体制。通常是先生成一对RSA密钥,其中之一是保密密钥,由用户保存;另一个为公开密钥,可对外公开,甚至可在网络服务器中注册。为提高保密强度,RSA密钥至少为500位长,一般推荐使用1024位,这就使加密的计算量很大。为减少计算量,在传送信息时,常采用传统加密方法与公开密钥加密方法相结合的方式,即信息采用改进的DES或IDEA对话密钥加密,然后使用RSA密钥加密对话密钥和信息摘要,对方收到信息后,用不同的密钥解密并可核对信息摘要。RSA算法是第一个能同时用于加密和数字签名的算法,也易于理解和操作,RSA是被研究得最广泛的公钥算法。RSA算法是一种非对称密码算法,所谓非对称,就是指该算法需要一对密钥,使用其中一个加密,则需要用另一个才能解密。RSA加密大体都应用在:本地数据加密、网络传输数据加密、方法体和方法名高级混淆以及程序结构混排加密。例如:对客户端传输数据提供加密方案,有效防止通过网络接口的拦截获取。
RSA的算法涉及三个参数,n、e1、e2。其中,n是两个大质数p、q的积,n的二进制表示时所占用的位数,就是所谓的密钥长度。e1和e2是一对相关的值,e1可以任意取,但要求e1与(p-1)(q-1)互质;再选择e2,要求(e2e1)mod((p-1)*(q-1))=1。(n,e1),(n,e2)就是密钥对。其中(n,e1)为公钥,(n,e2)为私钥;RSA加解密的算法完全相同,公钥加密体制中,一般用公钥加密,私钥解密。假设A为明文,B为密文,则:A=B^e2 mod n;B=A^e1 mod n;e1和e2可以互换使用,即私钥加密,公钥解密,公式:A=B^e1 mod n;B=A^e2 mod n;
RSA加解密特点:
- RSA密钥管理的方便,计算量很大速度相对比较慢。- RSA安全性很高,能够抵抗到目前为止已知的绝大多数密码攻击。
在线生成RSA密钥对的网址:在线生成非对称加密公钥私钥对等,RSA密钥格式请使用PKCS#8格式。PKCS#1与PKCS#8的区别还待后续查阅资料,再进行补充记录。
在iOS中RSA加解密的实现介绍(支持密钥文件<.pem>和字符串密钥)
/****************************RSAEncrypt.m类实现文件内容****************************/pragma mark - Class Utils Method+ (BOOL)isEmptyKeyRef:(id)object{ if (object == nil) { return YES; } else if (object == NULL) { return YES; } else if (object == [NSNull null]) { return YES; } return NO;}pragma mark - Private Method+ (SecKeyRef)getPrivateKeyRefWithFilePath:(NSString *)filePath keyPassword:(NSString *)keyPassword{ //读取私钥证书文件的内容 NSData *certificateData = [NSData dataWithContentsOfFile:filePath]; if ((certificateData == nil) || (certificateData == NULL)) { return nil; } else if (![certificateData isKindOfClass:[NSData class]]) { return nil; } else if ([certificateData length] <= 0) { return nil; } //拼接密码参数到字典中 NSString *passwordKey = (__bridge id)kSecImportExportPassphrase; NSString *passwordValue = [NSString stringWithFormat:@"%@",keyPassword]; if ((keyPassword == nil) || (keyPassword == NULL)) { passwordValue = @""; } else if (![keyPassword isKindOfClass:[NSString class]]) { passwordValue = @""; } else if ([keyPassword length] <= 0) { passwordValue = @""; } NSMutableDictionary *optionInfo = [[NSMutableDictionary alloc] init]; [optionInfo setObject:passwordValue forKey:passwordKey]; //获取私钥对象 SecKeyRef privateKeyRef = NULL; CFArrayRef items = CFArrayCreate(NULL, 0, 0, NULL); CFDataRef pkcs12Data = (__bridge CFDataRef)certificateData; CFDictionaryRef options = (__bridge CFDictionaryRef)optionInfo; OSStatus securityStatus = SecPKCS12Import(pkcs12Data, options, &items); if (securityStatus == noErr && CFArrayGetCount(items) > 0) { SecIdentityRef identity; const void *secpkey = kSecImportItemIdentity; CFDictionaryRef identityDict = CFArrayGetValueAtIndex(items, 0); identity = (SecIdentityRef)CFDictionaryGetValue(identityDict,secpkey); securityStatus = SecIdentityCopyPrivateKey(identity, &privateKeyRef); if (securityStatus != noErr) { privateKeyRef = NULL; } } CFRelease(items); return privateKeyRef;}+ (SecKeyRef)privateKeyRefWithPrivateKey:(NSString *)privateKey{ //判断参数是否正确 if ((privateKey == nil) || (privateKey == NULL)) { return nil; } else if (![privateKey isKindOfClass:[NSString class]]) { return nil; } else if ([privateKey length] <= 0) { return nil; } //解析私钥对象内容 NSString *pKey = [NSString stringWithFormat:@"%@",privateKey]; NSRange sposition = [pKey rangeOfString:@"-----BEGIN RSA PRIVATE KEY-----"]; NSRange eposition = [pKey rangeOfString:@"-----END RSA PRIVATE KEY-----"]; if (sposition.location != NSNotFound && eposition.location != NSNotFound) { NSUInteger endposition = eposition.location; NSUInteger startposition = sposition.location + sposition.length; NSRange range = NSMakeRange(startposition, endposition-startposition); pKey = [pKey substringWithRange:range]; } pKey = [pKey stringByReplacingOccurrencesOfString:@"\r" withString:@""]; pKey = [pKey stringByReplacingOccurrencesOfString:@"\n" withString:@""]; pKey = [pKey stringByReplacingOccurrencesOfString:@"\t" withString:@""]; pKey = [pKey stringByReplacingOccurrencesOfString:@" " withString:@""]; //This will be base64 encoded, decode it. NSData *keyData = [Base64 base64DecodeDataWithString:pKey]; keyData = [self stripPrivateKeyHeader:keyData]; if ((keyData == nil) || (keyData == NULL)) { return nil; } else if (![keyData isKindOfClass:[NSData class]]) { return nil; } else if ([keyData length] <= 0) { return nil; } //a tag to read/write keychain storage NSString *tag = @"RSAUtil_PrivKey"; const void *bytes = [tag UTF8String]; NSData *tagData = [NSData dataWithBytes:bytes length:[tag length]]; //Delete any old lingering key with the same tag NSMutableDictionary *attributes = [[NSMutableDictionary alloc] init]; [attributes setObject:(__bridge id)kSecClassKey forKey:(__bridge id)kSecClass]; [attributes setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType]; [attributes setObject:tagData forKey:(__bridge id)kSecAttrApplicationTag]; SecItemDelete((__bridge CFDictionaryRef)attributes); //Add persistent version of the key to system keychain [attributes setObject:keyData forKey:(__bridge id)kSecValueData]; [attributes setObject:(__bridge id)kSecAttrKeyClassPrivate forKey:(__bridge id)kSecAttrKeyClass]; [attributes setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecReturnPersistentRef]; OSStatus status = noErr; CFTypeRef persistKey = nil; status = SecItemAdd((__bridge CFDictionaryRef)attributes, &persistKey); if (persistKey != nil) {CFRelease(persistKey);} if ((status != noErr) && (status != errSecDuplicateItem)) { return nil; } [attributes removeObjectForKey:(__bridge id)kSecValueData]; [attributes removeObjectForKey:(__bridge id)kSecReturnPersistentRef]; [attributes setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecReturnRef]; [attributes setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType]; //Now fetch the SecKeyRef version of the key SecKeyRef keyRef = nil; CFDictionaryRef query = (__bridge CFDictionaryRef)attributes; status = SecItemCopyMatching(query, (CFTypeRef *)&keyRef); if (status != noErr) { return nil; } return keyRef;}+ (NSData *)stripPrivateKeyHeader:(NSData *)d_key{ //Skip ASN.1 private key header if (d_key == nil) return nil; unsigned long len = [d_key length]; if (!len) return nil; unsigned char *c_key = (unsigned char *)[d_key bytes]; unsigned int idx = 22; //magic byte at offset 22 if (0x04 != c_key[idx++]) return nil; //calculate length of the key unsigned int c_len = c_key[idx++]; if (!(c_len & 0x80)) { c_len = c_len & 0x7f; } else { int byteCount = c_len & 0x7f; if (byteCount + idx > len) { //rsa length field longer than buffer return nil; } unsigned int accum = 0; unsigned char *ptr = &c_key[idx]; idx += byteCount; while (byteCount) { accum = (accum << 8) + *ptr; ptr++; byteCount--; } c_len = accum; } //Now make a new NSData from this buffer return [d_key subdataWithRange:NSMakeRange(idx, c_len)];}+ (SecKeyRef)getPublicKeyRefWithFilePath:(NSString *)filePath{ //读取公钥证书文件的内容 NSData *certificateData = [NSData dataWithContentsOfFile:filePath]; if ((certificateData == nil) || (certificateData == NULL)) { return nil; } else if (![certificateData isKindOfClass:[NSData class]]) { return nil; } else if ([certificateData length] <= 0) { return nil; } //将公钥证书制作成证书对象 CFDataRef data = (__bridge CFDataRef)certificateData; SecCertificateRef certificateRef = SecCertificateCreateWithData(NULL, data); //获取公钥对象 SecTrustRef trust = NULL; SecKeyRef publicKey = NULL; SecPolicyRef policies = SecPolicyCreateBasicX509(); if (![[self class] isEmptyKeyRef:(__bridge id)(certificateRef)] && ![[self class] isEmptyKeyRef:(__bridge id)(policies)]) { OSStatus status; status = SecTrustCreateWithCertificates((CFTypeRef)certificateRef, policies, &trust); if (status == noErr) { SecTrustResultType result; if (SecTrustEvaluate(trust, &result) == noErr) { publicKey = SecTrustCopyPublicKey(trust); } } } if (certificateRef != NULL) CFRelease(certificateRef); if (policies != NULL) CFRelease(policies); if (trust != NULL) CFRelease(trust); return publicKey;}+ (SecKeyRef)publicKeyRefWithPublicKey:(NSString *)publicKey{ //判断参数是否正确 if ((publicKey == nil) || (publicKey == NULL)) { return nil; } else if (![publicKey isKindOfClass:[NSString class]]) { return nil; } else if ([publicKey length] <= 0) { return nil; } //解析公钥对象内容 NSString *pKey = [NSString stringWithFormat:@"%@",publicKey]; NSRange sposition = [pKey rangeOfString:@"-----BEGIN PUBLIC KEY-----"]; NSRange eposition = [pKey rangeOfString:@"-----END PUBLIC KEY-----"]; if (sposition.location != NSNotFound && eposition.location != NSNotFound) { NSUInteger startposition = eposition.location; NSUInteger endposition = sposition.location + sposition.length; NSRange range = NSMakeRange(endposition, startposition-endposition); pKey = [pKey substringWithRange:range]; } pKey = [pKey stringByReplacingOccurrencesOfString:@"\r" withString:@""]; pKey = [pKey stringByReplacingOccurrencesOfString:@"\n" withString:@""]; pKey = [pKey stringByReplacingOccurrencesOfString:@"\t" withString:@""]; pKey = [pKey stringByReplacingOccurrencesOfString:@" " withString:@""]; //This will be base64 encoded, decode it. NSData *keyData = [[self class] base64DecodeDataWithString:pKey]; keyData = [self stripPublicKeyHeader:keyData]; if ((keyData == nil) || (keyData == NULL)) { return nil; } else if (![keyData isKindOfClass:[NSData class]]) { return nil; } else if ([keyData length] <= 0) { return nil; } //a tag to read/write keychain storage NSString *tag = @"RSAUtil_PubKey"; const void *bytes = [tag UTF8String]; NSData *tagData = [NSData dataWithBytes:bytes length:[tag length]]; //Delete any old lingering key with the same tag NSMutableDictionary *attributes = [[NSMutableDictionary alloc] init]; [attributes setObject:(__bridge id)kSecClassKey forKey:(__bridge id)kSecClass]; [attributes setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType]; [attributes setObject:tagData forKey:(__bridge id)kSecAttrApplicationTag]; SecItemDelete((__bridge CFDictionaryRef)attributes); //Add persistent version of the key to system keychain [attributes setObject:keyData forKey:(__bridge id)kSecValueData]; [attributes setObject:(__bridge id)kSecAttrKeyClassPublic forKey:(__bridge id)kSecAttrKeyClass]; [attributes setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecReturnPersistentRef]; OSStatus status = noErr; CFTypeRef persistKey = nil; status = SecItemAdd((__bridge CFDictionaryRef)attributes, &persistKey); if (persistKey != nil) CFRelease(persistKey); if ((status != noErr) && (status != errSecDuplicateItem)) { return nil; } [attributes removeObjectForKey:(__bridge id)kSecValueData]; [attributes removeObjectForKey:(__bridge id)kSecReturnPersistentRef]; [attributes setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecReturnRef]; [attributes setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType]; //Now fetch the SecKeyRef version of the key SecKeyRef publicKeyRef = nil; CFDictionaryRef query = (__bridge CFDictionaryRef)attributes; status = SecItemCopyMatching(query, (CFTypeRef *)&publicKeyRef); if (status != noErr) { return nil; } return publicKeyRef;}+ (NSData *)stripPublicKeyHeader:(NSData *)d_key{ //Skip ASN.1 public key header if (d_key == nil) {return nil;} unsigned long len = [d_key length]; if (!len) return(nil); unsigned char *c_key = (unsigned char *)[d_key bytes]; unsigned int idx = 0; if (c_key[idx++] != 0x30) {return nil;} if (c_key[idx] > 0x80) { idx += c_key[idx] - 0x80 + 1; } else { idx++; } //PKCS #1 rsaEncryption szOID_RSA_RSA static unsigned char seqiod[] = {0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00}; if (memcmp(&c_key[idx], seqiod, 15)) {return nil;} idx += 15; if (c_key[idx++] != 0x03) {return nil;} if (c_key[idx] > 0x80) { idx += c_key[idx] - 0x80 + 1; } else { idx ++; } if (c_key[idx++] != '\0') {return nil;} //Now make a new NSData from this buffer return ([NSData dataWithBytes:&c_key[idx] length:len - idx]);}+ (NSData *)encryptData:(NSData *)data withKeyRef:(SecKeyRef)keyRef{ const uint8_t *srcbuf = (const uint8_t *)[data bytes]; size_t srclen = (size_t)data.length; size_t block_size = SecKeyGetBlockSize(keyRef) * sizeof(uint8_t); void *outbuf = malloc(block_size); size_t src_block_size = block_size - 11; NSMutableData *ret = [[NSMutableData alloc] init]; for (int idx = 0; idx < srclen; idx += src_block_size) { size_t data_len = srclen - idx; if(data_len > src_block_size){ data_len = src_block_size; } size_t outlen = block_size; OSStatus status = noErr; status = SecKeyEncrypt(keyRef, kSecPaddingPKCS1, srcbuf + idx, data_len, outbuf, &outlen); if (status != 0) { NSLog(@"SecKeyEncrypt fail. Error Code: %d", (int)status); ret = nil; break; } else { [ret appendBytes:outbuf length:outlen]; } } free(outbuf); CFRelease(keyRef); return ret;}+ (NSData *)decryptData:(NSData *)data withKeyRef:(SecKeyRef)keyRef{ const uint8_t *srcbuf = (const uint8_t *)[data bytes]; size_t srclen = (size_t)data.length; size_t block_size = SecKeyGetBlockSize(keyRef) * sizeof(uint8_t); UInt8 *outbuf = malloc(block_size); size_t src_block_size = block_size; NSMutableData *ret = [[NSMutableData alloc] init]; for (int idx = 0; idx < srclen; idx += src_block_size) { size_t data_len = srclen - idx; if(data_len > src_block_size) { data_len = src_block_size; } size_t outlen = block_size; OSStatus status = noErr; status = SecKeyDecrypt(keyRef, kSecPaddingNone, srcbuf + idx, data_len, outbuf, &outlen); if (status != 0) { NSLog(@"SecKeyEncrypt fail. Error Code: %d", (int)status); ret = nil; break; } else { int idxFirstZero = -1; int idxNextZero = (int)outlen; for (int i = 0; i < outlen; i ++) { if (outbuf[i] == 0) { if (idxFirstZero < 0) { idxFirstZero = i; } else { idxNextZero = i; break; } } } NSUInteger length = idxNextZero-idxFirstZero-1; [ret appendBytes:&outbuf[idxFirstZero+1] length:length]; } } free(outbuf); CFRelease(keyRef); return ret;}pragma mark - RSA Key File Encrypt/Decrypt Public Method+ (NSString *)encryptString:(NSString *)originString publicKeyPath:(NSString *)publicKeyPath{ //判断originString参数是否正确 if ((originString == nil) || (originString == NULL)) { return nil; } else if (![originString isKindOfClass:[NSString class]]) { return nil; } else if ([originString length] <= 0) { return nil; } //判断publicKeyPath参数是否正确 if ((publicKeyPath == nil) || (publicKeyPath == NULL)) { return nil; } else if (![publicKeyPath isKindOfClass:[NSString class]]) { return nil; } else if ([publicKeyPath length] <= 0) { return nil; } //获取公钥对象和需要加密的字符串内容编码数据流 SecKeyRef publicKeyRef = [self getPublicKeyRefWithFilePath:publicKeyPath]; NSData *originData = [originString dataUsingEncoding:NSUTF8StringEncoding]; if ([[self class] isEmptyKeyRef:(__bridge id)(publicKeyRef)]) { return nil; } if ((originData == nil) || (originData == NULL)) { return nil; } else if (![originData isKindOfClass:[NSData class]]) { return nil; } else if ([originData length] <= 0) { return nil; } //加密源字符串内容编码数据流的数据 NSData *resultData = nil; resultData = [self encryptData:originData withKeyRef:publicKeyRef]; return [[self class] base64EncodedStringWithData:resultData];}+ (NSString *)decryptString:(NSString *)encryptString privateKeyPath:(NSString *)privateKeyPath privateKeyPwd:(NSString *)privateKeyPwd{ //判断encryptString参数是否正确 if ((encryptString == nil) || (encryptString == NULL)) { return nil; } else if (![encryptString isKindOfClass:[NSString class]]) { return nil; } else if ([encryptString length] <= 0) { return nil; } //判断publicKeyPath参数是否正确 if ((privateKeyPath == nil) || (privateKeyPath == NULL)) { return nil; } else if (![privateKeyPath isKindOfClass:[NSString class]]) { return nil; } else if ([privateKeyPath length] <= 0) { return nil; } //判断密码是否存在 NSString *keyPassword = [NSString stringWithFormat:@"%@",privateKeyPwd]; if ((privateKeyPwd == nil) || (privateKeyPwd == NULL)) { keyPassword = @""; } else if (![privateKeyPwd isKindOfClass:[NSString class]]) { keyPassword = @""; } else if ([privateKeyPwd length] <= 0) { keyPassword = @""; } //获取私钥对象和需要加密的字符串内容编码数据流 NSData *encryptData = nil, *decryptData = nil; SecKeyRef privateKeyRef = [self getPrivateKeyRefWithFilePath:privateKeyPath keyPassword:privateKeyPwd]; encryptData = [[self class] base64DecodeDataWithString:encryptString]; if ([[self class] isEmptyKeyRef:(__bridge id)(privateKeyRef)]) { return nil; } if ((encryptData == nil) || (encryptData == NULL)) { return nil; } else if (![encryptData isKindOfClass:[NSData class]]) { return nil; } else if ([encryptData length] <= 0) { return nil; } NSStringEncoding encoding = NSUTF8StringEncoding; decryptData = [self decryptData:encryptData withKeyRef:privateKeyRef]; return [[NSString alloc] initWithData:decryptData encoding:encoding];}pragma mark - RSA Key String Encrypt/Decrypt Public Method+ (NSData *)encryptData:(NSData *)originData publicKey:(NSString *)publicKey{ //判断originData参数是否正确 if ((originData == nil) || (originData == NULL)) { return nil; } else if (![originData isKindOfClass:[NSData class]]) { return nil; } else if ([originData length] <= 0) { return nil; } //判断publicKeyPath参数是否正确 if ((publicKey == nil) || (publicKey == NULL)) { return nil; } else if (![publicKey isKindOfClass:[NSString class]]) { return nil; } else if ([publicKey length] <= 0) { return nil; } //获取需要加密的字符串内容编码数据流 SecKeyRef publicKeyRef = [self publicKeyRefWithPublicKey:publicKey]; if([[self class] isEmptyKeyRef:(__bridge id)(publicKeyRef)]){ return nil; } return [self encryptData:originData withKeyRef:publicKeyRef];}+ (NSString *)encryptString:(NSString *)originString publicKey:(NSString *)publicKey{ //判断publicKey参数是否正确 if ((publicKey == nil) || (publicKey == NULL)) { return nil; } else if (![publicKey isKindOfClass:[NSString class]]) { return nil; } else if ([publicKey length] <= 0) { return nil; } //判断originString参数是否正确 if ((originString == nil) || (originString == NULL)) { return nil; } else if (![originString isKindOfClass:[NSString class]]) { return nil; } else if ([originString length] <= 0) { return nil; } //获取需要加密的字符串内容编码数据流 NSData *originData = nil, *encryptData = nil; SecKeyRef publicKeyRef = [self publicKeyRefWithPublicKey:publicKey]; originData = [originString dataUsingEncoding:NSUTF8StringEncoding]; if([[self class] isEmptyKeyRef:(__bridge id)(publicKeyRef)]){ return nil; } if ((originData == nil) || (originData == NULL)) { return nil; } else if (![originData isKindOfClass:[NSData class]]) { return nil; } else if ([originData length] <= 0) { return nil; } encryptData = [self encryptData:originData withKeyRef:publicKeyRef]; return [[self class] base64EncodedStringWithData:encryptData];}+ (NSString *)decryptString:(NSString *)encryptString privateKey:(NSString *)privateKey{ //判断publicKey参数是否正确 if ((privateKey == nil) || (privateKey == NULL)) { return nil; } else if (![privateKey isKindOfClass:[NSString class]]) { return nil; } else if ([privateKey length] <= 0) { return nil; } //判断originString参数是否正确 if ((encryptString == nil) || (encryptString == NULL)) { return nil; } else if (![encryptString isKindOfClass:[NSString class]]) { return nil; } else if ([encryptString length] <= 0) { return nil; } //获取私钥对象和需要加密的字符串内容编码数据流 SecKeyRef privateKeyRef; NSData *encryptData = nil, *decryptData = nil; privateKeyRef = [[self class] privateKeyRefWithPrivateKey:privateKey]; encryptData = [[self class] base64DecodeDataWithString:encryptString]; if ([[self class] isEmptyKeyRef:(__bridge id)(privateKeyRef)]) { return nil; } if ((encryptData == nil) || (encryptData == NULL)) { return nil; } else if (![encryptData isKindOfClass:[NSData class]]) { return nil; } else if ([encryptData length] <= 0) { return nil; } NSStringEncoding encoding = NSUTF8StringEncoding; decryptData = [self decryptData:encryptData withKeyRef:privateKeyRef]; return [[NSString alloc] initWithData:decryptData encoding:encoding];}/******************************************************************************/
在iOS中RSA加解密使用方法介绍(RSA密钥格式请使用PKCS#8格式)
//使用RSA执行加密操作NSString *string4 = @"abcdefghijklmnopqrstuvwxyz";NSString *encodeString4 = [RSAEncrypt encryptString:string4 publicKey:mPublicKey];NSLog(@"encodeString4 : %@", encodeString4);//使用RSA执行解密操作NSString *decodeString4 = [RSAEncrypt decryptString:encodeString4 privateKey:mPrivateKey];NSLog(@"decodeString4 : %@", decodeString4);
github 地址:https://github.com/wenjing0628/encryptDemo
- iOS 常用的加密模式
- iOS常用的加密模式
- iOS 常用的加密方法
- iOS常用的加密方式
- iOS 中常用的几种加密
- iOS开发之常用的加密方法
- iOS开发常用的加密技术
- ios常用加密方法
- ios 常用加密
- iOS 常用加密
- iOS常用加密方法
- iOS常用加密
- iOS常用的设计模式
- iOS&Java常用加密(二)单向加密
- ios&java 常用加密(二)单向加密
- iOS&Java常用加密(二)单向加密
- iOS代码加密常用加密方式
- iOS代码加密常用加密方式
- Unity -- DoTween插件简介
- leetcode 刷题总结
- 客厅百寸私人影院 坚果S1激光电视6月上市
- 如何构建O2O场景,打造便捷高效的用户服务
- 小米无人机发布会汇总:对标大疆精灵,售价2499元起
- iOS常用的加密模式
- Java 字符串或字符串数组转为 List
- ubuntu无法链接wifi问题
- [python3.6]爬虫实战之爬取淘女郎图片
- 7. Reverse Integer
- SQL Sever 触发器
- 递归之全排列
- 程序员揭秘:左右脑年龄测试刷屏票圈的真实内幕
- 分形神经网络