Question

我看到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，但它会破坏构建并每天影响用户体验。服务器配置为建立安全连接，但不需要来自客户端的证书。

我在Java测试客户端和服务器上都打开了SSL调试输出（见下文）。我观察到的是，每当发生握手异常时，服务器似乎已经发送了客户端证书请求。我不明白为什么会这样做，为什么这只会偶尔发生。当它确实发送证书请求时，错误几乎总是发生，但是我也捕获了成功的请求（可能是1％的时间，99％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。

以下是日志中的片段：

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文件具有世界可读性。

2）客户登录（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（缩写）

[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)

在好的情况下，我们始终在客户端看不到“*** CertificateRequest”，并在服务器上输出如此

[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();

使用

运行

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

问题：

是什么让服务器发送证书请求，导致在客户端输出“*** CertificateRequest”？
设置“SSLVerifyClient none”是否阻止了证书请求？
关于下一步该看什么的任何建议？

更新：我注意到Java客户端在使用Java 6时从不显示错误。 Java 7和8以及Chrome，Internet Explorer和Firefox都会出现此问题。这似乎指向TLSv1.1或TLSv1.2的问题（另请参阅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

是什么让服务器发送证书请求，导致客户端上的输出“*** CertificateRequest”？

在服务器上调用SSL_CTX_set_client_CA_list。它是一系列杰出的名字。另请参阅SSL_CTX_set_client_CA_list man page。

服务器还需要调用SSL_CTX_load_verify_locations以建立对CA的信任。另请参阅SSL_CTX_load_verify_locations man page。

“SSLVerifyClient none”设置是否阻止了证书请求？

可能。从SSL_CTX_set_verify man page开始，您需要SSL_VERIFY_PEER，可能需要SSL_VERIFY_FAIL_IF_NO_PEER_CERT。

关于下一步要看什么的任何建议？

您应该显示相关的Java代码。

您应该说明服务器和客户端使用的OpenSSL版本。

Answer 2

是什么让服务器发送证书请求，导致客户端上的输出“*** CertificateRequest”？

某处您将SSLVerifyClient设置为'可选'或更高，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。这将覆盖全局设置的“SSLVerifyClient none”。

Answer 3

经过漫长而乏味的调试和分析后，我想报告调查结果。该问题与客户端发送的TLS握手的第一条Y消息有关。

Java 7和Java 8客户端（可能还有所有现代浏览器）都使用“服务器名称指示”（SNI）扩展。只有在使用此扩展时才会出现此问题。 Java 6客户端不发送它，并且问题从未发生过。 TLSv1和TLSv1.2出现问题 - 我们从未观察过TLSv1.1请求，因此无法发表评论。

对于Java 7和8客户端来防止此问题，我们可以设置background-image来阻止客户端发送SNI扩展。

我们将尝试更改.svg-icon.googleplus配置（和包含的文件）以查看我们是否可以让服务器运行良好。如果我们成功，我可以发布信息，即如果有服务器端解决方法。上面提到的Java交换机是一个客户端解决方案，至少对我们的夜间构建来说已经足够了。

Apache HTTP Server的间歇性SSL握手错误

3 个答案: