NSURLSession获得间歇性SSLHandshake失败(-9810)错误

Question

从安全墙后面的安全URL下载图像.像https://foo.com/bar.png这样的网址

有时我收到SSLHandshake错误.有时错误发生一次,但有时错误是不变的,我无法下载文件.

DownloadImageApp[2914] <Warning>: CHALLENGE!!! (NSURLAuthenticationMethodServerTrust)
DownloadImageApp[2914] <Warning>:    server = foo.com
DownloadImageApp[2914] <Warning>: CFNetwork SSLHandshake failed (-9810)
DownloadImageApp[2914] <Warning>: CHALLENGE!!! (NSURLAuthenticationMethodServerTrust)
DownloadImageApp[2914] <Warning>:    server = foo.com
DownloadImageApp[2914] <Warning>: CHALLENGE!!! (NSURLAuthenticationMethodNTLM)
DownloadImageApp[2914] <Warning>:    NSURLAuthenticationMethodNTLM

我使用以下代码来处理挑战

- (void)URLSession:(NSURLSession *)session didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition, NSURLCredential *))completionHandler {
    NSLog(@"CHALLENGE!!! (%@)", challenge.protectionSpace.authenticationMethod);

    if (challenge.error)
        NSLog(@"  -- error: %@", challenge.error.description);
    if (challenge.previousFailureCount > 0)
        NSLog(@"  -- previous failure count = %d", challenge.previousFailureCount);
    if (challenge.proposedCredential)
        NSLog(@"  -- proposed credential user: %@", challenge.proposedCredential.user);

    if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust]) {
        NSLog(@"   server = %@", challenge.protectionSpace.host);
        completionHandler(NSURLSessionAuthChallengeUseCredential, [NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust]);
    } else if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodNTLM]) {
        NSLog(@"   NSURLAuthenticationMethodNTLM");
        NSURLCredential *credential = [NSURLCredential credentialWithUser:@"username" password:@"passwordIsSecretShhh" persistence:NSURLCredentialPersistenceForSession];
        completionHandler(NSURLSessionAuthChallengeUseCredential, credential);
    } else {
        NSLog(@"   ????");
    }
}

即使它完全失败并且无法加载我仍然可以弹出到Safari,输入URL并加载它.所以我正在寻找可能导致此问题的想法,除了网络问题或托管网络服务器的不稳定问题.

Answer 1

我终于解决了这个问题。它与我的代码无关。

该问题是由服务器中安装的 Trend SSL 监控软件引起的。一旦软件被禁用，错误立即消失。

这不是一个很好的答案，但希望对其他人有帮助。