使用自签名证书在iOS 9中进行HTTPS请求

Question

我想用自签名证书向自定义服务器发出HTTPS请求.我使用NSURLConnection类和处理身份验证挑战，但总是在控制台中接收错误消息：

NSURLSession/NSURLConnection HTTP load failed (kCFStreamErrorDomainSSL, -9802)

然后，使用以下错误调用"connection:didFailWithError:“方法：

Error Domain=NSURLErrorDomain Code=-1200 "An SSL error has occurred and a secure connection to the server cannot be made." UserInfo={NSURLErrorFailingURLPeerTrustErrorKey=<SecTrustRef: 0x150094100>, NSLocalizedRecoverySuggestion=Would you like to connect to the server anyway?, _kCFStreamErrorDomainKey=3, _kCFStreamErrorCodeKey=-9802, NSErrorPeerCertificateChainKey=<CFArray 0x1500ddd90 [0x19f6dab68]>{type = immutable, count = 1, values = (
    0 : <cert(0x14e6fb370) s: (server certificate name) i: (custom CA name)>
)}, NSUnderlyingError=0x1504ae170 {Error Domain=kCFErrorDomainCFNetwork Code=-1200 "An SSL error has occurred and a secure connection to the server cannot be made." UserInfo={NSErrorFailingURLStringKey=https://217.92.80.156:9090/(method name and parameters), NSLocalizedRecoverySuggestion=Would you like to connect to the server anyway?, _kCFNetworkCFStreamSSLErrorOriginalValue=-9802, kCFStreamPropertySSLPeerCertificates=<CFArray 0x1500ddd90 [0x19f6dab68]>{type = immutable, count = 1, values = (
    0 : <cert(0x14e6fb370) s: (server certificate name) i: (custom CA name)>
)}, _kCFStreamPropertySSLClientCertificateState=2, kCFStreamPropertySSLPeerTrust=<SecTrustRef: 0x150094100>, NSLocalizedDescription=An SSL error has occurred and a secure connection to the server cannot be made., _kCFStreamPropertySSLClientCertificates=<CFArray 0x14e5ee8e0 [0x19f6dab68]>{type = mutable-small, count = 2, values = (
    0 : <SecIdentityRef: 0x15012cd40>
    1 : <cert(0x15014aa70) s: (client certificate name) i: (custom CA name)>
)}, _kCFStreamErrorDomainKey=3, NSErrorFailingURLKey=https://217.92.80.156:9090/(method name and parameters), _kCFStreamErrorCodeKey=-9802}}, NSErrorClientCertificateChainKey=<CFArray 0x14e5ee8e0 [0x19f6dab68]>{type = mutable-small, count = 2, values = (
    0 : <SecIdentityRef: 0x15012cd40>
    1 : <cert(0x15014aa70) s: (client certificate name) i: (custom CA name)>
)}, NSLocalizedDescription=An SSL error has occurred and a secure connection to the server cannot be made., NSErrorFailingURLKey=https://217.92.80.156:9090/(method name and parameters), NSErrorFailingURLStringKey=https://217.92.80.156:9090/(method name and parameters), NSErrorClientCertificateStateKey=2}

App接收两个身份验证挑战(NSURLAuthenticationMethodClientCertificate和NSURLAuthenticationMethodServerTrust)，并以下列方式处理它们：

- (void) connection:(NSURLConnection *)connection willSendRequestForAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge
{
    if(challenge.proposedCredential && !challenge.error)
    {
        [challenge.sender useCredential:challenge.proposedCredential forAuthenticationChallenge:challenge];

        return;
    }

    NSString *strAuthenticationMethod = challenge.protectionSpace.authenticationMethod;
    NSLog(@"authentication method: %@", strAuthenticationMethod);

    NSURLCredential *credential = nil;
    if([strAuthenticationMethod isEqualToString:NSURLAuthenticationMethodClientCertificate])
    {
        // get identity and certificate from p.12
        NSData *PKCS12Data = [NSData dataWithContentsOfFile:[[NSBundle mainBundle] pathForResource:@"client" ofType:@"p12"]];

        NSDictionary *optionsDictionary = [NSDictionary dictionaryWithObject:@"password" forKey:(__bridge id)kSecImportExportPassphrase];
        CFArrayRef items = CFArrayCreate(NULL, 0, 0, NULL);
        OSStatus securityError = SecPKCS12Import((__bridge CFDataRef)PKCS12Data,(__bridge CFDictionaryRef)optionsDictionary, &items);

        SecIdentityRef identity = NULL;
        SecCertificateRef certificate = NULL;
        if(securityError == errSecSuccess)
        { 
            CFDictionaryRef myIdentityAndTrust = CFArrayGetValueAtIndex(items, 0);
            identity = (SecIdentityRef)CFDictionaryGetValue (myIdentityAndTrust, kSecImportItemIdentity);

            CFArrayRef array = (CFArrayRef)CFDictionaryGetValue(myIdentityAndTrust, kSecImportItemCertChain);
            certificate = (SecCertificateRef)CFArrayGetValueAtIndex(array, 0);
        }

        credential = [NSURLCredential credentialWithIdentity:identity certificates:[NSArray arrayWithObject:(__bridge id)(certificate)] persistence:NSURLCredentialPersistenceNone];

        CFRelease(items);
    }
    else if([strAuthenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])
    {       
        int trustCertificateCount = (int)SecTrustGetCertificateCount(challenge.protectionSpace.serverTrust);
        NSMutableArray *trustCertificates = [[NSMutableArray alloc] initWithCapacity:trustCertificateCount];
        for(int i = 0; i < trustCertificateCount; i ++)
        {
            SecCertificateRef trustCertificate =  SecTrustGetCertificateAtIndex(challenge.protectionSpace.serverTrust, i);
            [trustCertificates addObject:(__bridge id) trustCertificate];
        }            

        SecPolicyRef policyRef = NULL;
        policyRef = SecPolicyCreateSSL(YES, (__bridge CFStringRef) challenge.protectionSpace.host);

        SecTrustRef trustRef = NULL;
        if(policyRef)
        {
            SecTrustCreateWithCertificates((__bridge CFArrayRef) trustCertificates, policyRef, &trustRef);
            CFRelease(policyRef);
        }

        if(trustRef)
        {
//          SecTrustSetAnchorCertificates(trustRef, (__bridge CFArrayRef) [NSArray array]);
//          SecTrustSetAnchorCertificatesOnly(trustRef, NO);

            SecTrustResultType result;
            OSStatus trustEvalStatus = SecTrustEvaluate(trustRef, &result);
            if(trustEvalStatus == errSecSuccess)
            {
                // just temporary attempt to make it working.
                // i hope, there is no such problem, when we have final working version of certificates.
                if(result == kSecTrustResultRecoverableTrustFailure)
                {
                    CFDataRef errDataRef = SecTrustCopyExceptions(trustRef);
                    SecTrustSetExceptions(trustRef, errDataRef);

                    SecTrustEvaluate(trustRef, &result);
                }

                if(result == kSecTrustResultProceed || result == kSecTrustResultUnspecified)
                    credential = [NSURLCredential credentialForTrust:trustRef];
            }

            CFRelease(trustRef);
        }
    }
    else
    {
        DDLogWarn(@"Unexpected authentication method. Cancelling authentication ...");
        [challenge.sender cancelAuthenticationChallenge:challenge];
    }

    if(credential)
        [challenge.sender useCredential:credential forAuthenticationChallenge:challenge];
    else
        [challenge.sender cancelAuthenticationChallenge:challenge];
}

在CFNetwork诊断日志中，我可以看到握手过程即将启动。至少，应用程序发送"ClientHello“消息，然后服务器发送其"ServerHello”消息，并要求进行身份验证。在这里，应用程序试图发送身份验证响应，但立即收到错误。(同时，在服务器日志中，我根本没有看到任何关于握手的消息)。以下是诊断日志的一部分：

Sep 15 10:51:49  AppName[331] <Notice>: CFNetwork Diagnostics [3:49] 10:51:49.185 {
    Authentication Challenge
       Loader: <CFURLRequest 0x1501931c0 [0x19f6dab68]> {url = https://217.92.80.156:9090/(method name and parameters), cs = 0x0}
    Challenge: challenge space https://217.92.80.156:9090/, ServerTrustEvaluationRequested (Hash f9810ad8165b3620)
    } [3:49]
Sep 15 10:51:49  AppName[331] <Notice>: CFNetwork Diagnostics [3:50] 10:51:49.189 {
    Use Credential
        Loader: <CFURLRequest 0x1501931c0 [0x19f6dab68]> {url = https://217.92.80.156:9090/(method name and parameters), cs = 0x0}
    Credential: Name: server, Persistence: session
    } [3:50]
Sep 15 10:51:49  AppName[331] <Notice>: CFNetwork Diagnostics [3:51] 10:51:49.190 {
     touchConnection
              Loader: <CFURLRequest 0x1501931c0 [0x19f6dab68]> {url = https://217.92.80.156:9090/(method name and parameters), cs = 0x0}
    Timeout Interval: 60.000 seconds
    } [3:51]
Sep 15 10:51:49  AppName[331] <Notice>: CFNetwork Diagnostics [3:52] 10:51:49.192 {
    Response Error
    Request: <CFURLRequest 0x14e5d02a0 [0x19f6dab68]> {url = https://217.92.80.156:9090/(method name and parameters), cs = 0x0}
      Error: Error Domain=kCFErrorDomainCFNetwork Code=-1200 "(null)" UserInfo={_kCFNetworkCFStreamSSLErrorOriginalValue=-9802, kCFStreamPropertySSLPeerCertificates=<CFArray 0x1500ddd90 [0x19f6dab68]>{type = immutable, count = 1, values = (
                0 : <cert(0x14e6fb370) s: (server certificate name) i: (custom CA name)>
             )}, _kCFStreamPropertySSLClientCertificateState=2, kCFStreamPropertySSLPeerTrust=<SecTrustRef: 0x150094100>, _kCFStreamPropertySSLClientCertificates=<CFArray 0x14e5ee8e0 [0x19f6dab68]>{type = mutable-small, count = 2, values = (
                0 : <SecIdentityRef: 0x15012cd40>
                1 : <cert(0x15014aa70) s: (client certificate name) i: (custom CA name)>
             )}, _kCFStreamErrorDomainKey=3, _kCFStreamErrorCodeKey=-9802}
    } [3:52]

我们的后端实例可以安装在客户端，所以我不能在Info.plist文件中设置任何域异常。另外，app可以以IPv4形式通过IP地址请求服务器，但不能通过域名(如我的示例中所示)请求服务器。

我试过什么：

• 用NSURLSession代替NSURLConnection，但没有成功；
• 检查了苹果对服务器实现这里的ATS要求(后端开发人员确信他的实现满足了所有这些要求)；
• 根据堆栈溢出和苹果开发者论坛中解决的各种问题，使用锚证书进行信任验证；
• 在开发者论坛上特别关注相似帖子及其相关的解决方案；

我正在iPad Air 2上测试iOS 9 GM种子(Build 13A340)和xCode 7 GM Seed (Build 7A218)上的https请求。重要注意:这个功能在iOS 8中运行良好。考虑到这一点，我可以假设，这个问题在我们的服务器上，但是我们的后端开发人员向我保证，所有事情都很好。

现在我没有主意了。如果有人能给我一个提示，或者至少提出一些其他的诊断建议，这比“致命警报”更具体，我将不胜感激。

谢谢。

编辑1: SecTrustEvaluate总是返回kSecTrustResultRecoverableTrustFailure，这就是我必须找到某种解决办法的原因。

Answer 1

这个问题一段时间前就解决了。结果证明是无效的自签名证书。它并不能满足苹果公司的所有要求。不幸的是我不知道到底是什么。

Answer 2

根据这一点：https://forums.developer.apple.com/message/36842#36842

修复HTTP失败(kCFStreamErrorDomainSSL，-9802)的最佳方法是在info.plist文件中设置一个异常，如下所示：

<key>NSAppTransportSecurity</key>
<dict>
  <key>NSExceptionDomains</key>
  <dict>
    <key>test.testdomain.com</key>
    <dict>
      <key>NSIncludesSubdomains</key>
      <true/>
      <key>NSExceptionAllowsInsecureHTTPLoads</key>
      <true/>
    </dict>
  </dict>
</dict>

重要的一点是，这并不比iOS8安全，只是不像iOS9支持的完整ATS那样安全。

Answer 3

您是否使用nscurl来诊断连接问题？如果您的Mac操作系统运行OSXv10.11，您可以运行如下所示：

/usr/bin/nscurl --ats-diagnostics https://www.yourdomain.com

或者，如果您没有10.11，您可以在这里下载示例代码：https://developer.apple.com/library/mac/samplecode/SC1236/并使用XCode构建它，并按如下方式运行它(根据您的计算机需要更改路径)：

/Users/somebody/Library/Developer/Xcode/DerivedData/TLSTool-hjuytnjaqebcfradighsrffxxyzq/Build/Products/Debug/TLSTool s_client -connect www.yourdomain.com:443

(要找到上述内容的完整路径，在构建完之后，打开中的Products组，右键单击TLSTool和"Show“。)

你已经在这个话题上链接到苹果的technote，https://developer.apple.com/library/prerelease/ios/technotes/App-Transport-Security-Technote/，但是你没有说你是否运行nscurl。