java - Apache HTTP Server 的间歇性 SSL 握手错误

Question

我发现 Java 客户端和浏览器通过 Apache HTTP 服务器访问站点时出现间歇性 SSL 握手错误。这种情况很少发生，但它每天都会破坏构建并影响用户体验。服务器配置为建立安全连接，但不需要来自客户端的证书。

我已经在 J​​ava 测试客户端和服务器上打开了 SSL 调试输出(见下文)。我观察到的是，每当发生握手异常时，服务器似乎已发送了对客户端证书的请求。我不明白为什么它会这样做，为什么这只是偶尔发生。当它确实发送证书请求时，几乎总是会发生错误，但是我也捕获了成功的请求(可能有 1% 的时间，99% 的失败)。

客户端使用Java 8 (1.8.0_31-b13)，Apache HTTP服务器版本为2.2.19。

以下是日志的片段:

1) Apache 配置摘录

SSLProtocol ALL -SSLv2 -SSLv3
SSLCertificateFile <path-to-pem1>
SSLCertificateChainFile <path-to-pem2>
SSLCACertificateFile <path-to-pem3>
SSLVerifyDepth 10
SSLVerifyClient none

.pem 文件是全局可读的。

2) 客户端日志(严重缩写)

*** ClientHello, TLSv1.2
***
*** ServerHello, TLSv1
***
*** Certificate chain
***
*** Diffie-Hellman ServerKeyExchange
*** CertificateRequest
*** ServerHelloDone
*** Certificate chain
***
*** ClientKeyExchange, DH
*** Finished
***
...
main, WRITE: TLSv1 Handshake, length = 48
main, waiting for close_notify or alert: state 1
main, Exception while waiting for close java.net.SocketException: Software caused connection abort: recv failed
main, handling exception: java.net.SocketException: Software caused connection abort: recv failed
%% Invalidated:  [Session-1, TLS_DHE_RSA_WITH_AES_128_CBC_SHA]
main, SEND TLSv1 ALERT:  fatal, description = unexpected_message
...
main, WRITE: TLSv1 Alert, length = 32
main, Exception sending alert: java.net.SocketException: Software caused connection abort: socket write error
main, called closeSocket()

3)服务器日志(略)

[info] [client x.x.x.x] Connection to child 1 established (server XXX:443)
[info] Seeding PRNG with 0 bytes of entropy
[debug] ssl_engine_kernel.c(1866): OpenSSL: Handshake: start
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: before/accept initialization
[debug] ssl_engine_io.c(1897): OpenSSL: read 11/11 bytes from BIO#82f6820 [mem: 82c5290] (BIO dump follows)
[debug] ssl_engine_io.c(1830): +-------------------------------------------------------------------------+
[debug] ssl_engine_io.c(1869): | 0000: XX XX XX XX XX XX XX XX-XX XX XX                 ...........      |
[debug] ssl_engine_io.c(1875): +-------------------------------------------------------------------------+
[debug] ssl_engine_io.c(1897): OpenSSL: read 245/245 bytes from BIO#82f6820 [mem: 82c529b] (BIO dump follows)
[debug] ssl_engine_io.c(1830): +-------------------------------------------------------------------------+
[debug] ssl_engine_io.c(1869): | 0000: XX XX XX XX XX XX XX XX-XX XX XX XX XX XX XX XX  ................ |
...
[debug] ssl_engine_io.c(1869): | 00f0: XX XX XX XX XX                                   .....            |
[debug] ssl_engine_io.c(1875): +-------------------------------------------------------------------------+
[debug] ssl_engine_kernel.c(1987): [client x.x.x.x] SSL virtual host for servername XXX found
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 read client hello A
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 write server hello A
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 write certificate A
[debug] ssl_engine_kernel.c(1274): [client x.x.x.x] handing out temporary 1024 bit DH key
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 write key exchange A
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 write certificate request A
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 flush data
[debug] ssl_engine_io.c(1897): OpenSSL: read 5/5 bytes from BIO#82f6820 [mem: 82c5290] (BIO dump follows)
[debug] ssl_engine_io.c(1830): +-------------------------------------------------------------------------+
[debug] ssl_engine_io.c(1869): | 0000: 16 03 01 00 8d                                   .....            |
[debug] ssl_engine_io.c(1875): +-------------------------------------------------------------------------+
[debug] ssl_engine_io.c(1897): OpenSSL: read 141/141 bytes from BIO#82f6820 [mem: 82c5295] (BIO dump follows)
[debug] ssl_engine_io.c(1830): +-------------------------------------------------------------------------+
[debug] ssl_engine_io.c(1869): | 0000: XX XX XX XX XX XX XX XX-XX XX XX XX XX XX XX XX  ................ |
...
[debug] ssl_engine_io.c(1869): | 0080: XX XX XX XX XX XX XX XX-XX XX XX XX XX           .............    |
[debug] ssl_engine_io.c(1875): +-------------------------------------------------------------------------+
[debug] ssl_engine_kernel.c(1884): OpenSSL: Write: SSLv3 read client certificate B
[debug] ssl_engine_kernel.c(1903): OpenSSL: Exit: error in SSLv3 read client certificate B
[debug] ssl_engine_kernel.c(1903): OpenSSL: Exit: error in SSLv3 read client certificate B
[info] [client x.x.x.x] SSL library error 1 in handshake (server XXX:443)
[info] SSL Library Error: 336105671 error:140890C7:SSL routines:SSL3_GET_CLIENT_CERTIFICATE:peer did not return a certificate No CAs known to server for verification?
[info] [client x.x.x.x] Connection closed to child 1 with abortive shutdown (server XXX:443)

在良好的情况下，我们始终在客户端上看不到“*** CertificateRequest”并在服务器上输出这样的内容

[debug] ssl_engine_kernel.c(1987): [client x.x.x.x] SSL virtual host for servername XXX found
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 read client hello A
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 write server hello A
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 write certificate A
[debug] ssl_engine_kernel.c(1274): [client x.x.x.x] handing out temporary 1024 bit DH key
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 write key exchange A
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 write server done A
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 flush data
[debug] ssl_engine_io.c(1897): OpenSSL: read 5/5 bytes from BIO#82d82d8 [mem: 82c8790] (BIO dump follows)
[debug] ssl_engine_io.c(1830): +-------------------------------------------------------------------------+
[debug] ssl_engine_io.c(1869): | 0000: 16 03 01 00 86                                   .....            |
[debug] ssl_engine_io.c(1875): +-------------------------------------------------------------------------+
[debug] ssl_engine_io.c(1897): OpenSSL: read 134/134 bytes from BIO#82d82d8 [mem: 82c8795] (BIO dump follows)
[debug] ssl_engine_io.c(1830): +-------------------------------------------------------------------------+
[debug] ssl_engine_io.c(1869): | 0000: XX XX XX XX XX XX XX XX-XX XX XX XX XX XX XX XX  ................ |
...
[debug] ssl_engine_io.c(1869): | 0080: XX XX XX XX XX XX                                ......           |
[debug] ssl_engine_io.c(1875): +-------------------------------------------------------------------------+
[debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: SSLv3 read client key exchange A

Java 客户端代码大纲:

URL url = new URL("https://...");
HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
connection.setRequestProperty("Authorization", "Basic " + DatatypeConverter.printBase64Binary((user + ":" + pass).getBytes(Charset.forName("UTF-8"))));
connection.setReadTimeout(60*1000);
connection.setUseCaches(false);
connection.connect();

运行

java -Djavax.net.ssl.trustStore=... -Djavax.net.ssl.trustStoreType=jks -Djavax.net.ssl.trustStorePassword=... -Djavax.net.debug=all ...

问题:

1. 是什么让服务器发送证书请求，导致在客户端输出“*** CertificateRequest”？
2. 设置“SSLVerifyClient none”是否不会阻止证书请求？
3. 对下一步要看什么有什么建议吗？

更新:我注意到在使用 Java 6 时，Java 客户端从不显示错误。该问题出现在 Java 7 和 8，以及 Chrome、Internet Explorer 和 Firefox 中。这似乎指向 TLSv1.1 或 TLSv1.2 的问题(另请参见 https://serverfault.com/questions/513961/how-to-disable-tls-1-1-1-2-in-apache“OpenSSL v1.0.1 与 TLSv1.2 存在一些已知问题”)。我将尝试至少检查在 Java 客户端中禁用 TLSv1.1/2 是否会使问题消失。

Answer 1

What makes the server send the certificate request, causing the ouput "*** CertificateRequest" on the client?

您在某处将 SSLVerifyClient 设置为“可选”或更高级别，可能在 .htaccess 文件中，这就是您无法在配置文件中找到它的原因。这会覆盖全局设置的“SSLVerifyClient none”。