既然说到加密,必然和隐私相关,那么就从网络开发两大原则说起:
1-网络上不允许传输用户的明文隐私数据。
2-本地不允许保存用户的额明文隐私数据。
那么既然不能使用明文进行传输和保存,我们同时又需要进行相关操作的话,就必须要使用下面说到的各种加密了。
首先,市面上常用的加密方式分为对称加密
,非对称加密
和哈希加密
。
1.对称加密:
文件加密和解密使用相同的密钥,即加密密钥也可以用作解密密钥。
常用加密算法有DES
,3DES
,AES
等.
DES 数据加密标准(用的比较少,因为强度不够).
3DES 使用3个密钥,对相同的数据执行三次加密,强度增强.
AES 高级加密标准,目前美国国家安全局使用AES加密,苹果的钥匙串访问就是使用AES加密。
而对称加密一般分为四种模式:ECB
,CBC
,CFB
和OFB
,最为常见的是前两种。
ECB的特点:
加密文件会被分为若干个加密块,
每个块都是独立进行加密,互不影响。
所以,如果变动数据中的某一个地方,
加密之后其对应得块也会发生变化,
缺点是一旦被破解某个模块,就可以进行推理,
进而有机会获取到重要数据。
关于ECB的终端操作代码:
加密: $ openssl enc -des-ecb -K 616263 -nosalt -in
msg.txt -out msgLock.bin
解密:$ openssl enc -des-ecb -K 616263 -nosalt -in
msgLock.bin -out msg.txt -d
查看加密之后的二进制文件:$ xxd msgLock.bin
CBC的特点:
使用一个密钥和一个初始化向量 (IV)对数据执
行加密转换。
加密文件同样会被分为若干个加密块,
每个块都依赖于上一个加密块进行加密,互相牵制。
所以,如果变动数据中的某一个地方,
加密之后整体数据都会发生变化。
可以有效地保证密文的完整性
关于CBC的终端操作代码:
加密: $ openssl enc -des-cbc -K 616263 -iv
0000000000000000 -nosalt -in a.txt -out
msg1.bin
解密:$ openssl enc -des-cbc -K 616263 -iv
0000000000000000 -nosalt -in msg1.bin -out
msg4.txt -d
查看加密之后的二进制文件:$ xxd msg1.bin
2.非对称加密
与对称加密算法不同,非对称加密算法需要两个密钥:公开密钥(publickey)和私有密钥(privatekey)。也就是公钥加密,私钥解密或者私钥加密,公钥解密。常见的非对称加密算法有RSA
(加密,证书生成),DSA
(数字签名)等,非对称加密算法的保密性比较好,但加密和解密花费时间长、速度慢,它不适合于对文件加密而只适用于对少量数据进行加密。
使用openssl生成密钥加密的步骤:
生成强度是 512 的 RSA 私钥:$ openssl genrsa -out private.pem 512
以明文输出私钥内容:$ openssl rsa -in private.pem -text -out
private.txt
校验私钥文件:$ openssl rsa -in private.pem -check
从私钥中提取公钥:$ openssl rsa -in private.pem -out public.pem
-outform PEM -pubout
以明文输出公钥内容:$ openssl rsa -in public.pem -out public.txt
-pubin -pubout -text
使用公钥加密小文件:$ openssl rsautl -encrypt -pubin -inkey
public.pem -in msg.txt -out msg.bin
使用私钥解密小文件:$ openssl rsautl -decrypt -inkey private.pem
-in msg.bin -out a.txt
将私钥转换成 DER 格式:$ openssl rsa -in private.pem -out private.der
-outform der
将公钥转换成 DER 格式:$ openssl rsa -in public.pem -out public.der
-pubin -outform der
程序开发数字证书的生成:
生成私钥:openssl genrsa -out ca.key 1024
创建证书请求:openssl req -new -key ca.key -out rsacert.csr
生成证书并签名,有效期10年:openssl x509 -req -days 3650 -in rsacert.csr
-signkey ca.key -out rsacert.crt
转换格式(将 openssl默认生成的PEM 格式文件转换成iOS支持的DER 格式):openssl x509 -outform der -in rsacert.crt -out
rsacert.der
导入P12文件:openssl pkcs12 -export -out p.p12 -inkey
ca.key -in rsacert.crt
iOS开发中相关的函数:
使用公钥对数据加密:SecKeyEncrypt
使用私钥对数据解密:SecKeyDecrypt
使用公钥对数字签名进行验证:SecKeyRawVerify
使用私钥生成数字签名:SecKeyRawSign
3.HASH加密
Hash算法特别的地方在于它是一种单向算法,用户可以通过Hash算法对目标信息生成一段特定长度(32个字符)的唯一的Hash值,却不能通过这个Hash值重新获得目标信息。对用相同数据,加密之后的密文相同。
常见的Hash算法有MD5
和SHA
。
由于加密结果固定,所以基本上原始的哈希加密已经不再安全,于是衍生出了加盐的方式。
加盐:先对原始数据拼接固定的字符串再进行加密。
HMAC:也叫随机盐,给定一个密钥,对明文进行拼接,
并且做两次散列。其中密钥由服务器在用户注册时候返回给客户端。
iOS对称加密代码:
//AES - ECB 加密
NSString * key = @"hk";
//加密
NSLog(@"加密: %@",[[EncryptionTools sharedEncryptionTools] encryptString:@"hello" keyString:key iv:nil]);
//解密
NSLog(@"解密: %@",[[EncryptionTools sharedEncryptionTools] decryptString:@"cKRPM1ALLG+0q5qCjADoaQ==" keyString:key iv:nil]);
//AES - CBC 加密
uint8_t iv[8] = {2,3,4,5,6,7,0,0}; //直接影响加密结果!
NSData * ivData = [NSData dataWithBytes:iv length:sizeof(iv)];
NSLog(@"CBC加密: %@",[[EncryptionTools sharedEncryptionTools] encryptString:@"hello" keyString:key iv:ivData]);
NSLog(@"CBC解密: %@", [[EncryptionTools sharedEncryptionTools] decryptString:@"+dv/u4juE0WE3S9XSFyibA==" keyString:key iv:ivData]);
//DES - ECB 加密
[EncryptionTools sharedEncryptionTools].algorithm = kCCAlgorithmDES;
NSLog(@"DES 加密%@",[[EncryptionTools sharedEncryptionTools] encryptString:@"hello" keyString:key iv:nil]);
NSLog(@"DES 解密: %@", [[EncryptionTools sharedEncryptionTools] decryptString:@"vTuv8E5AlWQ=" keyString:key iv:nil]);
其中EncryptionTools
文件如下:
#import
#import
/**
* 终端测试指令
*
* DES(ECB)加密
* $ echo -n hello | openssl enc -des-ecb -K 616263 -nosalt | base64
*
* DES(CBC)加密
* $ echo -n hello | openssl enc -des-cbc -iv 0102030405060708 -K 616263 -nosalt | base64
*
* AES(ECB)加密
* $ echo -n hello | openssl enc -aes-128-ecb -K 616263 -nosalt | base64
*
* AES(CBC)加密
* $ echo -n hello | openssl enc -aes-128-cbc -iv 0102030405060708 -K 616263 -nosalt | base64
*
* DES(ECB)解密
* $ echo -n HQr0Oij2kbo= | base64 -D | openssl enc -des-ecb -K 616263 -nosalt -d
*
* DES(CBC)解密
* $ echo -n alvrvb3Gz88= | base64 -D | openssl enc -des-cbc -iv 0102030405060708 -K 616263 -nosalt -d
*
* AES(ECB)解密
* $ echo -n d1QG4T2tivoi0Kiu3NEmZQ== | base64 -D | openssl enc -aes-128-ecb -K 616263 -nosalt -d
*
* AES(CBC)解密
* $ echo -n u3W/N816uzFpcg6pZ+kbdg== | base64 -D | openssl enc -aes-128-cbc -iv 0102030405060708 -K 616263 -nosalt -d
*
* 提示:
* 1> 加密过程是先加密,再base64编码
* 2> 解密过程是先base64解码,再解密
*/
@interface EncryptionTools : NSObject
+ (instancetype)sharedEncryptionTools;
/**
@constant kCCAlgorithmAES 高级加密标准,128位(默认)
@constant kCCAlgorithmDES 数据加密标准
*/
@property (nonatomic, assign) uint32_t algorithm;
/**
* 加密字符串并返回base64编码字符串
*
* @param string 要加密的字符串
* @param keyString 加密密钥
* @param iv 初始化向量(8个字节)
*
* @return 返回加密后的base64编码字符串
*/
- (NSString *)encryptString:(NSString *)string keyString:(NSString *)keyString iv:(NSData *)iv;
/**
* 解密字符串
*
* @param string 加密并base64编码后的字符串
* @param keyString 解密密钥
* @param iv 初始化向量(8个字节)
*
* @return 返回解密后的字符串
*/
- (NSString *)decryptString:(NSString *)string keyString:(NSString *)keyString iv:(NSData *)iv;
@end
#import "EncryptionTools.h"
@interface EncryptionTools()
@property (nonatomic, assign) int keySize;
@property (nonatomic, assign) int blockSize;
@end
@implementation EncryptionTools
+ (instancetype)sharedEncryptionTools {
static EncryptionTools *instance;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
instance = [[self alloc] init];
instance.algorithm = kCCAlgorithmAES;
});
return instance;
}
- (void)setAlgorithm:(uint32_t)algorithm {
_algorithm = algorithm;
switch (algorithm) {
case kCCAlgorithmAES:
self.keySize = kCCKeySizeAES128;
self.blockSize = kCCBlockSizeAES128;
break;
case kCCAlgorithmDES:
self.keySize = kCCKeySizeDES;
self.blockSize = kCCBlockSizeDES;
break;
default:
break;
}
}
- (NSString *)encryptString:(NSString *)string keyString:(NSString *)keyString iv:(NSData *)iv {
// 设置秘钥
NSData *keyData = [keyString dataUsingEncoding:NSUTF8StringEncoding];
uint8_t cKey[self.keySize];
bzero(cKey, sizeof(cKey));
[keyData getBytes:cKey length:self.keySize];
// 设置iv
/*
kCCOptionPKCS7Padding CBC 的加密方式
kCCOptionPKCS7Padding | kCCOptionECBMode ECB 的加密方式
*/
uint8_t cIv[self.blockSize];
bzero(cIv, self.blockSize);
int option = 0;
if (iv) {
[iv getBytes:cIv length:self.blockSize];
option = kCCOptionPKCS7Padding;
} else {
option = kCCOptionPKCS7Padding | kCCOptionECBMode;
}
// 设置输出缓冲区
NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];
size_t bufferSize = [data length] + self.blockSize;
void *buffer = malloc(bufferSize);
// 开始加密
size_t encryptedSize = 0;
/***
CCCrypt 对称加密算法的核心函数(加密/解密)
参数:
1.kCCEncrypt 加密/kCCDecrypt 解密
2.加密算法,默认使用的是 AES/DES
3.加密选项 ECB/CBC
kCCOptionPKCS7Padding CBC 的加密方式
kCCOptionPKCS7Padding | kCCOptionECBMode ECB 的加密方式
4.加密密钥
5.密钥长度
6.iv 初始化向量,ECB 不需要指定
7.加密的数据
8.加密的数据的长度
9.密文的内存地址
10.密文缓冲区的大小
11.加密结果大小
*/
CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt,
self.algorithm,
option,
cKey,
self.keySize,
cIv,
[data bytes],
[data length],
buffer,
bufferSize,
&encryptedSize);
NSData *result = nil;
if (cryptStatus == kCCSuccess) {
result = [NSData dataWithBytesNoCopy:buffer length:encryptedSize];
} else {
free(buffer);
NSLog(@"[错误] 加密失败|状态编码: %d", cryptStatus);
}
return [result base64EncodedStringWithOptions:0];
}
- (NSString *)decryptString:(NSString *)string keyString:(NSString *)keyString iv:(NSData *)iv {
// 设置秘钥
NSData *keyData = [keyString dataUsingEncoding:NSUTF8StringEncoding];
uint8_t cKey[self.keySize];
bzero(cKey, sizeof(cKey));
[keyData getBytes:cKey length:self.keySize];
// 设置iv
uint8_t cIv[self.blockSize];
bzero(cIv, self.blockSize);
int option = 0;
if (iv) {
[iv getBytes:cIv length:self.blockSize];
option = kCCOptionPKCS7Padding;
} else {
option = kCCOptionPKCS7Padding | kCCOptionECBMode;
}
// 设置输出缓冲区
NSData *data = [[NSData alloc] initWithBase64EncodedString:string options:0];
size_t bufferSize = [data length] + self.blockSize;
void *buffer = malloc(bufferSize);
// 开始解密
size_t decryptedSize = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt,
self.algorithm,
option,
cKey,
self.keySize,
cIv,
[data bytes],
[data length],
buffer,
bufferSize,
&decryptedSize);
NSData *result = nil;
if (cryptStatus == kCCSuccess) {
result = [NSData dataWithBytesNoCopy:buffer length:decryptedSize];
} else {
free(buffer);
NSLog(@"[错误] 解密失败|状态编码: %d", cryptStatus);
}
return [[NSString alloc] initWithData:result encoding:NSUTF8StringEncoding];
}
@end
iOS RSA加密代码:
- (void)viewDidLoad {
[super viewDidLoad];
//1.加载公钥
[[RSACryptor sharedRSACryptor] loadPublicKey:[[NSBundle mainBundle] pathForResource:@"rsacert.der" ofType:nil]];
//2. 加载私钥 - P12的文件 password : 生成P12 的时候设置的密码
[[RSACryptor sharedRSACryptor] loadPrivateKey:[[NSBundle mainBundle] pathForResource:@"p.p12" ofType:nil] password:@"123456"];
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
NSData * reault = [[RSACryptor sharedRSACryptor] encryptData:[@"hello" dataUsingEncoding:NSUTF8StringEncoding]];
//base64 编码
NSString * base64 = [reault base64EncodedStringWithOptions:0];
NSLog(@"加密的信息: %@",base64);
//解密
NSData * jiemi = [[RSACryptor sharedRSACryptor] decryptData:reault];
NSLog(@"%@",[[NSString alloc]initWithData:jiemi encoding:NSUTF8StringEncoding]);
}
RSACryptor
文件如下:
#import
@interface RSACryptor : NSObject
+ (instancetype)sharedRSACryptor;
/**
* 生成密钥对
*
* @param keySize 密钥尺寸,可选数值(512/1024/2048)
*/
- (void)generateKeyPair:(NSUInteger)keySize;
/**
* 加载公钥
*
* @param publicKeyPath 公钥路径
*
@code
# 生成证书
$ openssl genrsa -out ca.key 1024
# 创建证书请求
$ openssl req -new -key ca.key -out rsacert.csr
# 生成证书并签名
$ openssl x509 -req -days 3650 -in rsacert.csr -signkey ca.key -out rsacert.crt
# 转换格式
$ openssl x509 -outform der -in rsacert.crt -out rsacert.der
@endcode
*/
- (void)loadPublicKey:(NSString *)publicKeyPath;
/**
* 加载私钥
*
* @param privateKeyPath p12文件路径
* @param password p12文件密码
*
@code
openssl pkcs12 -export -out p.p12 -inkey ca.key -in rsacert.crt
@endcode
*/
- (void)loadPrivateKey:(NSString *)privateKeyPath password:(NSString *)password;
/**
* 加密数据
*
* @param plainData 明文数据
*
* @return 密文数据
*/
- (NSData *)encryptData:(NSData *)plainData;
/**
* 解密数据
*
* @param cipherData 密文数据
*
* @return 明文数据
*/
- (NSData *)decryptData:(NSData *)cipherData;
@end
#import "RSACryptor.h"
// 填充模式
// kSecPaddingNone 每次加密结果是固定的 kSecPaddingPKCS1 是随机的
#define kTypeOfWrapPadding kSecPaddingPKCS1
// 公钥/私钥标签
#define kPublicKeyTag "com.itheima.sample.publickey"
#define kPrivateKeyTag "com.itheima.sample.privatekey"
static const uint8_t publicKeyIdentifier[] = kPublicKeyTag;
static const uint8_t privateKeyIdentifier[] = kPrivateKeyTag;
@interface RSACryptor() {
SecKeyRef publicKeyRef; // 公钥引用
SecKeyRef privateKeyRef; // 私钥引用
}
@property (nonatomic, retain) NSData *publicTag; // 公钥标签
@property (nonatomic, retain) NSData *privateTag; // 私钥标签
@end
@implementation RSACryptor
+ (instancetype)sharedRSACryptor {
static id instance;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
instance = [[self alloc] init];
});
return instance;
}
- (instancetype)init {
self = [super init];
if (self) {
// 查询密钥的标签
_privateTag = [[NSData alloc] initWithBytes:privateKeyIdentifier length:sizeof(privateKeyIdentifier)];
_publicTag = [[NSData alloc] initWithBytes:publicKeyIdentifier length:sizeof(publicKeyIdentifier)];
}
return self;
}
#pragma mark - 加密 & 解密数据
- (NSData *)encryptData:(NSData *)plainData {
OSStatus sanityCheck = noErr;
size_t cipherBufferSize = 0;
size_t keyBufferSize = 0;
NSAssert(plainData != nil, @"明文数据为空");
NSAssert(publicKeyRef != nil, @"公钥为空");
NSData *cipher = nil;
uint8_t *cipherBuffer = NULL;
// 计算缓冲区大小
cipherBufferSize = SecKeyGetBlockSize(publicKeyRef);
keyBufferSize = [plainData length];
if (kTypeOfWrapPadding == kSecPaddingNone) {
NSAssert(keyBufferSize <= cipherBufferSize, @"加密内容太大");
} else {
NSAssert(keyBufferSize <= (cipherBufferSize - 11), @"加密内容太大");
}
// 分配缓冲区
cipherBuffer = malloc(cipherBufferSize * sizeof(uint8_t));
memset((void *)cipherBuffer, 0x0, cipherBufferSize);
// 使用公钥加密
sanityCheck = SecKeyEncrypt(publicKeyRef,
kTypeOfWrapPadding,
(const uint8_t *)[plainData bytes],
keyBufferSize,
cipherBuffer,
&cipherBufferSize
);
NSAssert(sanityCheck == noErr, @"加密错误,OSStatus == %d", sanityCheck);
// 生成密文数据
cipher = [NSData dataWithBytes:(const void *)cipherBuffer length:(NSUInteger)cipherBufferSize];
if (cipherBuffer) free(cipherBuffer);
return cipher;
}
- (NSData *)decryptData:(NSData *)cipherData {
OSStatus sanityCheck = noErr;
size_t cipherBufferSize = 0;
size_t keyBufferSize = 0;
NSData *key = nil;
uint8_t *keyBuffer = NULL;
SecKeyRef privateKey = NULL;
privateKey = [self getPrivateKeyRef];
NSAssert(privateKey != NULL, @"私钥不存在");
// 计算缓冲区大小
cipherBufferSize = SecKeyGetBlockSize(privateKey);
keyBufferSize = [cipherData length];
NSAssert(keyBufferSize <= cipherBufferSize, @"解密内容太大");
// 分配缓冲区
keyBuffer = malloc(keyBufferSize * sizeof(uint8_t));
memset((void *)keyBuffer, 0x0, keyBufferSize);
// 使用私钥解密
sanityCheck = SecKeyDecrypt(privateKey,
kTypeOfWrapPadding,
(const uint8_t *)[cipherData bytes],
cipherBufferSize,
keyBuffer,
&keyBufferSize
);
NSAssert1(sanityCheck == noErr, @"解密错误,OSStatus == %d", sanityCheck);
// 生成明文数据
key = [NSData dataWithBytes:(const void *)keyBuffer length:(NSUInteger)keyBufferSize];
if (keyBuffer) free(keyBuffer);
return key;
}
#pragma mark - 密钥处理
/**
* 生成密钥对
*/
- (void)generateKeyPair:(NSUInteger)keySize {
OSStatus sanityCheck = noErr;
publicKeyRef = NULL;
privateKeyRef = NULL;
NSAssert1((keySize == 512 || keySize == 1024 || keySize == 2048), @"密钥尺寸无效 %tu", keySize);
// 删除当前密钥对
[self deleteAsymmetricKeys];
// 容器字典
NSMutableDictionary *privateKeyAttr = [[NSMutableDictionary alloc] init];
NSMutableDictionary *publicKeyAttr = [[NSMutableDictionary alloc] init];
NSMutableDictionary *keyPairAttr = [[NSMutableDictionary alloc] init];
// 设置密钥对的顶级字典
[keyPairAttr setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];
[keyPairAttr setObject:[NSNumber numberWithUnsignedInteger:keySize] forKey:(__bridge id)kSecAttrKeySizeInBits];
// 设置私钥字典
[privateKeyAttr setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecAttrIsPermanent];
[privateKeyAttr setObject:_privateTag forKey:(__bridge id)kSecAttrApplicationTag];
// 设置公钥字典
[publicKeyAttr setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecAttrIsPermanent];
[publicKeyAttr setObject:_publicTag forKey:(__bridge id)kSecAttrApplicationTag];
// 设置顶级字典属性
[keyPairAttr setObject:privateKeyAttr forKey:(__bridge id)kSecPrivateKeyAttrs];
[keyPairAttr setObject:publicKeyAttr forKey:(__bridge id)kSecPublicKeyAttrs];
// SecKeyGeneratePair 返回密钥对引用
sanityCheck = SecKeyGeneratePair((__bridge CFDictionaryRef)keyPairAttr, &publicKeyRef, &privateKeyRef);
NSAssert((sanityCheck == noErr && publicKeyRef != NULL && privateKeyRef != NULL), @"生成密钥对失败");
}
/**
* 加载公钥
*/
- (void)loadPublicKey:(NSString *)publicKeyPath {
NSAssert(publicKeyPath.length != 0, @"公钥路径为空");
// 删除当前公钥
if (publicKeyRef) CFRelease(publicKeyRef);
// 从一个 DER 表示的证书创建一个证书对象
NSData *certificateData = [NSData dataWithContentsOfFile:publicKeyPath];
SecCertificateRef certificateRef = SecCertificateCreateWithData(kCFAllocatorDefault, (__bridge CFDataRef)certificateData);
NSAssert(certificateRef != NULL, @"公钥文件错误");
// 返回一个默认 X509 策略的公钥对象,使用之后需要调用 CFRelease 释放
SecPolicyRef policyRef = SecPolicyCreateBasicX509();
// 包含信任管理信息的结构体
SecTrustRef trustRef;
// 基于证书和策略创建一个信任管理对象
OSStatus status = SecTrustCreateWithCertificates(certificateRef, policyRef, &trustRef);
NSAssert(status == errSecSuccess, @"创建信任管理对象失败");
// 信任结果
SecTrustResultType trustResult;
// 评估指定证书和策略的信任管理是否有效
status = SecTrustEvaluate(trustRef, &trustResult);
NSAssert(status == errSecSuccess, @"信任评估失败");
// 评估之后返回公钥子证书
publicKeyRef = SecTrustCopyPublicKey(trustRef);
NSAssert(publicKeyRef != NULL, @"公钥创建失败");
if (certificateRef) CFRelease(certificateRef);
if (policyRef) CFRelease(policyRef);
if (trustRef) CFRelease(trustRef);
}
/**
* 加载私钥
*/
- (void)loadPrivateKey:(NSString *)privateKeyPath password:(NSString *)password {
NSAssert(privateKeyPath.length != 0, @"私钥路径为空");
// 删除当前私钥
if (privateKeyRef) CFRelease(privateKeyRef);
NSData *PKCS12Data = [NSData dataWithContentsOfFile:privateKeyPath];
CFDataRef inPKCS12Data = (__bridge CFDataRef)PKCS12Data;
CFStringRef passwordRef = (__bridge CFStringRef)password;
// 从 PKCS #12 证书中提取标示和证书
SecIdentityRef myIdentity;
SecTrustRef myTrust;
const void *keys[] = {kSecImportExportPassphrase};
const void *values[] = {passwordRef};
CFDictionaryRef optionsDictionary = CFDictionaryCreate(NULL, keys, values, 1, NULL, NULL);
CFArrayRef items = CFArrayCreate(NULL, 0, 0, NULL);
// 返回 PKCS #12 格式数据中的标示和证书
OSStatus status = SecPKCS12Import(inPKCS12Data, optionsDictionary, &items);
if (status == noErr) {
CFDictionaryRef myIdentityAndTrust = CFArrayGetValueAtIndex(items, 0);
myIdentity = (SecIdentityRef)CFDictionaryGetValue(myIdentityAndTrust, kSecImportItemIdentity);
myTrust = (SecTrustRef)CFDictionaryGetValue(myIdentityAndTrust, kSecImportItemTrust);
}
if (optionsDictionary) CFRelease(optionsDictionary);
NSAssert(status == noErr, @"提取身份和信任失败");
SecTrustResultType trustResult;
// 评估指定证书和策略的信任管理是否有效
status = SecTrustEvaluate(myTrust, &trustResult);
NSAssert(status == errSecSuccess, @"信任评估失败");
// 提取私钥
status = SecIdentityCopyPrivateKey(myIdentity, &privateKeyRef);
NSAssert(status == errSecSuccess, @"私钥创建失败");
}
/**
* 删除非对称密钥
*/
- (void)deleteAsymmetricKeys {
OSStatus sanityCheck = noErr;
NSMutableDictionary *queryPublicKey = [[NSMutableDictionary alloc] init];
NSMutableDictionary *queryPrivateKey = [[NSMutableDictionary alloc] init];
// 设置公钥查询字典
[queryPublicKey setObject:(__bridge id)kSecClassKey forKey:(__bridge id)kSecClass];
[queryPublicKey setObject:_publicTag forKey:(__bridge id)kSecAttrApplicationTag];
[queryPublicKey setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];
// 设置私钥查询字典
[queryPrivateKey setObject:(__bridge id)kSecClassKey forKey:(__bridge id)kSecClass];
[queryPrivateKey setObject:_privateTag forKey:(__bridge id)kSecAttrApplicationTag];
[queryPrivateKey setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];
// 删除私钥
sanityCheck = SecItemDelete((__bridge CFDictionaryRef)queryPrivateKey);
NSAssert1((sanityCheck == noErr || sanityCheck == errSecItemNotFound), @"删除私钥错误,OSStatus == %d", sanityCheck);
// 删除公钥
sanityCheck = SecItemDelete((__bridge CFDictionaryRef)queryPublicKey);
NSAssert1((sanityCheck == noErr || sanityCheck == errSecItemNotFound), @"删除公钥错误,OSStatus == %d", sanityCheck);
if (publicKeyRef) CFRelease(publicKeyRef);
if (privateKeyRef) CFRelease(privateKeyRef);
}
/**
* 获得私钥引用
*/
- (SecKeyRef)getPrivateKeyRef {
OSStatus sanityCheck = noErr;
SecKeyRef privateKeyReference = NULL;
if (privateKeyRef == NULL) {
NSMutableDictionary * queryPrivateKey = [[NSMutableDictionary alloc] init];
// 设置私钥查询字典
[queryPrivateKey setObject:(__bridge id)kSecClassKey forKey:(__bridge id)kSecClass];
[queryPrivateKey setObject:_privateTag forKey:(__bridge id)kSecAttrApplicationTag];
[queryPrivateKey setObject:(__bridge id)kSecAttrKeyTypeRSA forKey:(__bridge id)kSecAttrKeyType];
[queryPrivateKey setObject:[NSNumber numberWithBool:YES] forKey:(__bridge id)kSecReturnRef];
// 获得密钥
sanityCheck = SecItemCopyMatching((__bridge CFDictionaryRef)queryPrivateKey, (CFTypeRef *)&privateKeyReference);
if (sanityCheck != noErr) {
privateKeyReference = NULL;
}
} else {
privateKeyReference = privateKeyRef;
}
return privateKeyReference;
}
@end