NSURLSession http转Https

1.设置代理

NSURLSession *sesson = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration] delegate:self delegateQueue:[[NSOperationQueue alloc]init]];

2.在代理方法中实现对证书的操作 

方法一：这是在开发者足够信任后端的安全的情况下做的，比如调个接口，这样做的结果就是忽略证书的验证，直接信任。

- (void)URLSession:(NSURLSession *)session didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition, NSURLCredential * _Nullable))completionHandler{

    if([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust]){//服务器信任证书

        NSURLCredential *credential = [NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust];//服务器信任证书

        if(completionHandler)

        completionHandler(NSURLSessionAuthChallengeUseCredential,credential);

    }

}

方法二：可以把证书加到工程中，然后https访问时在代理方法中进行证书的验证

- (void)URLSession:(NSURLSession *)session didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition, NSURLCredential * _Nullable))completionHandler{

    SecTrustRef servertrust = challenge.protectionSpace.serverTrust;

    SecCertificateRef certi= SecTrustGetCertificateAtIndex(servertrust, 0);

    NSData *certidata = CFBridgingRelease(CFBridgingRetain(CFBridgingRelease(SecCertificateCopyData(certi))));

    NSString *path = [[NSBundle mainBundle] pathForResource:@"https" ofType:@"cer"];

    NSData *localCertiData = [NSData dataWithContentsOfFile:path];

    if ([certidata isEqualToData:localCertiData]) {

        NSURLCredential *credential = [[NSURLCredential alloc] initWithTrust:servertrust];

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

        completionHandler(NSURLSessionAuthChallengeUseCredential, credential);

        NSLog(@"服务端证书认证通过");

    }else {

        completionHandler(NSURLSessionAuthChallengeCancelAuthenticationChallenge, nil);

        NSLog(@"服务端认证失败");

    }

}