Question

从安全墙后面的安全网址下载图片。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。

问题是导致服务器中安装的Trend SSL监控软件。一旦软件被禁用，错误就会立即消失。

这不是一个好的答案，但希望它会帮助别人。

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

1 个答案: