iOS开发 - 用AFNetworking实现https单向验证，双向验证

https相关

自苹果宣布2017年1月1日开始强制使用https以来，htpps慢慢成为大家讨论的对象之一，不是说此前https没有出现，只是这一决策让得开发者始料未及，博主在15年的时候就做过https的接口，深知此坑之深，原因就是自身对这方面知识不了解加上网上的资料少，除此外还有博客不知对错就互相转载，导致当时网上几乎找不到能用的代码，这一点，博主说的毫不夸张。

鉴于此，博主一直想填一下这个坑，多增加一些正确的代码，来供广大开发者使用，后来一直被搁置，经过尝试后，博主现将整理好的代码发布在这里，希望能帮到焦急寻找的开发者。

1.先来说说老的AFNetworking2.x怎么来实现的 
博主在网上看过几篇帖子，其中说的一些方法是正确的，但是却并不全对，由于那几篇博客几乎一样，博主不能确定最早的那篇是谁写的，所以就重新在下面说明下方法：

1）倒入client.p12证书；

2）在plist文件做如图配置： 

各个项代表的含义请看这篇博客，博主写的很详细：http://blog.csdn.net/zhouzhoujianquan/article/details/53401506 除了一些说明，对方也提供了一些代码，大家可以拿来相互印证；

3）在AFNetworking中修改一个类： 
 
找到这个文件，在里面增加一个方法：

- (OSStatus)extractIdentity:(CFDataRef)inP12Data toIdentity:(SecIdentityRef*)identity {
    OSStatus securityError = errSecSuccess;
    CFStringRef password = CFSTR("证书密码");
    const void *keys[] = { kSecImportExportPassphrase };
    const void *values[] = { password };
    CFDictionaryRef options = CFDictionaryCreate(NULL, keys, values, 1, NULL, NULL);
    CFArrayRef items = CFArrayCreate(NULL, 0, 0, NULL);
    securityError = SecPKCS12Import(inP12Data, options, &items);
    if (securityError == 0)
    {
        CFDictionaryRef ident = CFArrayGetValueAtIndex(items,0);
        const void *tempIdentity = NULL;
        tempIdentity = CFDictionaryGetValue(ident, kSecImportItemIdentity);
        *identity = (SecIdentityRef)tempIdentity;
    }
    if (options) {
        CFRelease(options);
    }
    return securityError;
}

再修改一个方法：

用下面的这段代码替换NSURLConnectionDelegate中的同名代码，
- (void)connection:(NSURLConnection *)connection
willSendRequestForAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge
{
    NSString *thePath = [[NSBundle mainBundle] pathForResource:@"client" ofType:@"p12"];
    //倒入证书       NSLog(@"thePath===========%@",thePath);
    NSData *PKCS12Data = [[NSData alloc] initWithContentsOfFile:thePath];
    CFDataRef inPKCS12Data = (__bridge CFDataRef)PKCS12Data;

    SecIdentityRef identity = NULL;
    // extract the ideneity from the certificate
    [self extractIdentity :inPKCS12Data toIdentity:&identity];

    SecCertificateRef certificate = NULL;
    SecIdentityCopyCertificate (identity, &certificate);

    const void *certs[] = {certificate};
    //                        CFArrayRef certArray = CFArrayCreate(kCFAllocatorDefault, certs, 1, NULL);
    // create a credential from the certificate and ideneity, then reply to the challenge with the credential
    //NSLog(@"identity=========%@",identity);
    NSURLCredential *credential = [NSURLCredential credentialWithIdentity:identity certificates:nil persistence:NSURLCredentialPersistencePermanent];

    //           credential = [NSURLCredential credentialWithIdentity:identity certificates:(__bridge NSArray*)certArray persistence:NSURLCredentialPersistencePermanent];

    [challenge.sender useCredential:credential forAuthenticationChallenge:challenge];

}

4）发起请求

  NSString *url = @"xxxxxxxxxx";
    // 1.获得请求管理者
    AFHTTPRequestOperationManager *mgr = [AFHTTPRequestOperationManager manager];
    //2设置https 请求
    AFSecurityPolicy *securityPolicy = [AFSecurityPolicy policyWithPinningMode:AFSSLPinningModeCertificate];
    securityPolicy.allowInvalidCertificates = YES;
    mgr.securityPolicy = securityPolicy;
    // 3.发送POST请求

    [mgr POST:url parameters:nil success:^(AFHTTPRequestOperation * _Nonnull operation, id  _Nonnull responseObject) {
        NSLog(@"responseObject: %@", responseObject);

    } failure:^(AFHTTPRequestOperation * _Nonnull operation, NSError * _Nonnull error) {
        NSLog(@"Error: %@", error);

    }];

---

到此，老版的AFNetworking请求https接口的双向验证就做完了，但是有一个问题，这里需要改动AFNetworking的代码，何况新的AFNetworking已经有了，为了保持代码的活力，老的应该摒弃的，而且更新pods后肯定替换的代码就没了，也是一个问题，不要急，下面来说说怎么用新的AFNetworking，并解决被pods更新替换代码的问题。

最后再说一点，使用老的AF来请求，只用到了client.p12文件，并没有用到server.cer，在新的里面是有用到的，猜测可能是客户端选择信任任何证书导致的，就变成了单向的验证。

Demo放在最后

2.来说说新的AFNetworking3.x怎么来实现的

1）倒入client.p12和server.cer文件 
2）plist内的设置，这是和上面一样的： 

各个项代表的含义请看这篇博客，博主写的很详细：http://blog.csdn.net/zhouzhoujianquan/article/details/53401506 除了一些说明，对方也提供了一些代码，大家可以拿来相互印证；

3）这里可不需要修改类里面的代码，但是这里需要重写一个方法：

  NSString *url = @"https://test.niuniuhaoguanjia.com/3.0.0/?service=City.GetCityList";

    NSString *certFilePath = [[NSBundle mainBundle] pathForResource:@"server" ofType:@"cer"];
    NSData *certData = [NSData dataWithContentsOfFile:certFilePath];
    NSSet *certSet = [NSSet setWithObject:certData];
    AFSecurityPolicy *policy = [AFSecurityPolicy policyWithPinningMode:AFSSLPinningModeCertificate withPinnedCertificates:certSet];
    policy.allowInvalidCertificates = YES;
    policy.validatesDomainName = NO;

    _manager = [AFHTTPSessionManager manager];
    _manager.securityPolicy = policy;
    _manager.requestSerializer = [AFHTTPRequestSerializer serializer];
    _manager.responseSerializer = [AFHTTPResponseSerializer serializer];
    _manager.responseSerializer.acceptableContentTypes =  [NSSet setWithObjects:@"application/json", @"text/json", @"text/javascript",@"text/plain", nil];
    //关闭缓存避免干扰测试r
    _manager.requestSerializer.cachePolicy = NSURLRequestReloadIgnoringLocalCacheData;
    [_manager setSessionDidBecomeInvalidBlock:^(NSURLSession * _Nonnull session, NSError * _Nonnull error) {
        NSLog(@"setSessionDidBecomeInvalidBlock");
    }];
    //客户端请求验证 重写 setSessionDidReceiveAuthenticationChallengeBlock 方法
    __weak typeof(self)weakSelf = self;
    [_manager setSessionDidReceiveAuthenticationChallengeBlock:^NSURLSessionAuthChallengeDisposition(NSURLSession*session, NSURLAuthenticationChallenge *challenge, NSURLCredential *__autoreleasing*_credential) {
        NSURLSessionAuthChallengeDisposition disposition = NSURLSessionAuthChallengePerformDefaultHandling;
        __autoreleasing NSURLCredential *credential =nil;
        if([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust]) {
            if([weakSelf.manager.securityPolicy evaluateServerTrust:challenge.protectionSpace.serverTrust forDomain:challenge.protectionSpace.host]) {
                credential = [NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust];
                if(credential) {
                    disposition =NSURLSessionAuthChallengeUseCredential;
                } else {
                    disposition =NSURLSessionAuthChallengePerformDefaultHandling;
                }
            } else {
                disposition = NSURLSessionAuthChallengeCancelAuthenticationChallenge;
            }
        } else {
            // client authentication
            SecIdentityRef identity = NULL;
            SecTrustRef trust = NULL;
            NSString *p12 = [[NSBundle mainBundle] pathForResource:@"client"ofType:@"p12"];
            NSFileManager *fileManager =[NSFileManager defaultManager];

            if(![fileManager fileExistsAtPath:p12])
            {
                NSLog(@"client.p12:not exist");
            }
            else
            {
                NSData *PKCS12Data = [NSData dataWithContentsOfFile:p12];

                if ([[weakSelf class]extractIdentity:&identity andTrust:&trust fromPKCS12Data:PKCS12Data])
                {
                    SecCertificateRef certificate = NULL;
                    SecIdentityCopyCertificate(identity, &certificate);
                    const void*certs[] = {certificate};
                    CFArrayRef certArray =CFArrayCreate(kCFAllocatorDefault, certs,1,NULL);
                    credential =[NSURLCredential credentialWithIdentity:identity certificates:(__bridge  NSArray*)certArray persistence:NSURLCredentialPersistencePermanent];
                    disposition =NSURLSessionAuthChallengeUseCredential;
                }
            }
        }
        *_credential = credential;
        return disposition;
    }];

关于这段代码，其实和老的AF里面修改的道理是一样的，可以看下这篇文章：http://www.jianshu.com/p/9e573607be13

4）发起请求

//第三步和这一步代码是放在一起的，请注意哦
   [_manager GET:url parameters:nil progress:^(NSProgress * _Nonnull downloadProgress) {

    } success:^(NSURLSessionDataTask * _Nonnull task, id  _Nullable responseObject) {
        NSDictionary *dic = [NSJSONSerialization JSONObjectWithData:responseObject options:NSJSONReadingMutableContainers error:nil];
        NSLog(@"JSON: %@", dic);
    } failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
        NSLog(@"Error: %@", error);

        NSData *data = [error.userInfo objectForKey:@"com.alamofire.serialization.response.error.data"];
        NSString *str = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding];
        NSLog(@"%@",str);
    }];

另外还要加上一个方法：

+(BOOL)extractIdentity:(SecIdentityRef*)outIdentity andTrust:(SecTrustRef *)outTrust fromPKCS12Data:(NSData *)inPKCS12Data {
    OSStatus securityError = errSecSuccess;
    //client certificate password
    NSDictionary*optionsDictionary = [NSDictionary dictionaryWithObject:@"证书密码"
                                                                 forKey:(__bridge id)kSecImportExportPassphrase];

    CFArrayRef items = CFArrayCreate(NULL, 0, 0, NULL);
    securityError = SecPKCS12Import((__bridge CFDataRef)inPKCS12Data,(__bridge CFDictionaryRef)optionsDictionary,&items);

    if(securityError == 0) {
        CFDictionaryRef myIdentityAndTrust =CFArrayGetValueAtIndex(items,0);
        const void*tempIdentity =NULL;
        tempIdentity= CFDictionaryGetValue (myIdentityAndTrust,kSecImportItemIdentity);
        *outIdentity = (SecIdentityRef)tempIdentity;
        const void*tempTrust =NULL;
        tempTrust = CFDictionaryGetValue(myIdentityAndTrust,kSecImportItemTrust);
        *outTrust = (SecTrustRef)tempTrust;
    } else {
        NSLog(@"Failedwith error code %d",(int)securityError);
        return NO;
    }
    return YES;
}

你会发现http://www.jianshu.com/p/9e573607be13 这里的代码有冗余，没错，我们是要封装一下，可是要怎么封装呢？博主尝试了集中都失败了，真是百思不得解，相信主动去封装的开发者也会碰到封装后请求失败的问题，也许你成功了，但是这里需要注意一个在block内使用变量的问题，具体的可以去看博主怎么封装的。

---

到这里，新的AF请求https就已经结束了，想看封装的，Demo放在最后。

3.单向验证 
说到这个，不得不说一下网上的很多方法，都把单向验证当作双向的，其实也是并不理解其原理，关于原理，请看这里 
代码实现AF都是一样的：

//AF加上这句和下面的方法
    _manager.securityPolicy = [self customSecurityPolicy];

/**** SSL Pinning ****/
- (AFSecurityPolicy*)customSecurityPolicy {
    NSString *cerPath = [[NSBundle mainBundle] pathForResource:@"server" ofType:@"cer"];
    NSData *certData = [NSData dataWithContentsOfFile:cerPath];
    AFSecurityPolicy *securityPolicy = [AFSecurityPolicy policyWithPinningMode:AFSSLPinningModeCertificate];
    [securityPolicy setAllowInvalidCertificates:YES];
    NSSet *set = [NSSet setWithObjects:certData, nil];
    [securityPolicy setPinnedCertificates:@[certData]];
    /**** SSL Pinning ****/
    return securityPolicy;
}

4.Demo下载福利

因为证书安全问题，Demo 里的证书博主删除了，请见谅，请大家放入自己的证书。 
老的AF访问httpsDemo

新的AF访问httpsDemo