Swoole 在 v4.6.0 版本中对 SNI 进行了反对,这篇文章就对这个新个性进行一些演示和阐明。
先来理解一下什么是 SNI 协定?
Server Name Identification 简称 SNI,是一个扩大的 TLS 计算机联网协定,用来解决一个服务器领有多个域名的状况。
在该协定下,在握手过程开始时通过客户端通知它正在连接的服务器的主机名称。这容许服务器在雷同的 IP 地址和 TCP 端口号上出现多个证书,并且因而容许在雷同的 IP 地址上提供多个平安 HTTPS 网站(或其余任何基于 TLS 的服务),而不须要所有这些站点应用雷同的证书。
那么如果一台服务器有多个虚拟主机,而且每个主机的域名不一样,应用了不一样的证书,该和哪个主机进行通信?
和 HTTP 协定用来解决服务器多域名的计划相似,HTTP 在申请头中应用 Host 字段来指定要拜访的域名。
而 TLS 的做法也是增加 Host,在客户端收回 SSL 申请中的 Client Hello 阶段进行增加,这样就能够让服务器可能切换到正确的域并返回相应的证书。
在 Swoole 的 GitHub 中也有一个 Issue (#4031),想让 Swoole 的 HTTP Server 反对通过 Hostname 来配置 SSL 信息。
实际上是 Swoole 在 #3908 中曾经进行了反对,不过英文网站的文档还没来及更新,所以没有找到相干阐明。
上面就来演示 Swoole 如何设置 SNI:
首先先下载证书,这里间接应用 Swoole 测试的证书
<code class="bash">wget -r -np -nd -P ./ssl_certs https://cdn.jsdelivr.net/gh/swoole/[email protected]/tests/include/ssl_certs/
下载实现后会寄存在当前目录下的ssl_certs
目录中
再来创立一个 HTTP Server
<code class="php">use Swoole\Http\Request; use Swoole\Http\Response; use Swoole\Http\Server; $http = new Server('0.0.0.0', 9501); $http->on('request', function (Request $request, Response $response) { $response->end('Hello Swoole'); }); $http->start();
这里就须要用到一个新增的 ssl_sni_certs 选项
ssl_sni_certs
的参数是一个二维数组,key 为 Hostname,value 是对应的证书配置
<code class="php">$http->set([ 'ssl_sni_certs' => [ 'cs.php.net' => [ 'ssl_cert_file' => SSL_FILE_DIR . '/sni_server_cs_cert.pem', 'ssl_key_file' => SSL_FILE_DIR . '/sni_server_cs_key.pem' ], 'uk.php.net' => [ 'ssl_cert_file' => SSL_FILE_DIR . '/sni_server_uk_cert.pem', 'ssl_key_file' => SSL_FILE_DIR . '/sni_server_uk_key.pem' ], 'us.php.net' => [ 'ssl_cert_file' => SSL_FILE_DIR . '/sni_server_us_cert.pem', 'ssl_key_file' => SSL_FILE_DIR . '/sni_server_us_key.pem', ], ] ]);
配置一下 Server 的 sock_type 来反对 SSL,以及对应的证书配置,就有了如下代码
<code class="php">use Swoole\Http\Request; use Swoole\Http\Response; use Swoole\Http\Server; define('SSL_FILE_DIR', __DIR__ . '/ssl_certs'); $http = new Server('127.0.0.1', 9501, SWOOLE_BASE, SWOOLE_SOCK_TCP | SWOOLE_SSL); $http->set([ 'log_file' => '/dev/null', 'ssl_cert_file' => SSL_FILE_DIR . '/server.crt', 'ssl_key_file' => SSL_FILE_DIR . '/server.key', 'ssl_protocols' => SWOOLE_SSL_TLSv1_2 | SWOOLE_SSL_TLSv1_3 | SWOOLE_SSL_TLSv1_1 | SWOOLE_SSL_SSLv2, 'ssl_sni_certs' => [ 'cs.php.net' => [ 'ssl_cert_file' => SSL_FILE_DIR . '/sni_server_cs_cert.pem', 'ssl_key_file' => SSL_FILE_DIR . '/sni_server_cs_key.pem' ], 'uk.php.net' => [ 'ssl_cert_file' => SSL_FILE_DIR . '/sni_server_uk_cert.pem', 'ssl_key_file' => SSL_FILE_DIR . '/sni_server_uk_key.pem' ], 'us.php.net' => [ 'ssl_cert_file' => SSL_FILE_DIR . '/sni_server_us_cert.pem', 'ssl_key_file' => SSL_FILE_DIR . '/sni_server_us_key.pem', ], ] ]); $http->on('request', function (Request $request, Response $response) { $response->end('Hello Swoole'); }); $http->start();
搞个客户端来测试一下
<code class="php">$flags = STREAM_CLIENT_CONNECT; $port = 9501; $ctxArr = [ 'cafile' => SSL_FILE_DIR . '/sni_server_ca.pem', 'capture_peer_cert' => true, 'verify_peer' => false, ]; $ctxArr['peer_name'] = 'cs.php.net'; $ctx = stream_context_create(['ssl' => $ctxArr]); $client = stream_socket_client("tls://127.0.0.1:$port", $errno, $errstr, 1, $flags, $ctx); $cert = stream_context_get_options($ctx)['ssl']['peer_certificate']; var_dump(openssl_x509_parse($cert)['subject']['CN']); $ctxArr['peer_name'] = 'uk.php.net'; $ctx = stream_context_create(['ssl' => $ctxArr]); $client = stream_socket_client("tls://127.0.0.1:$port", $errno, $errstr, 1, $flags, $ctx); $cert = stream_context_get_options($ctx)['ssl']['peer_certificate']; var_dump(openssl_x509_parse($cert)['subject']['CN']); $ctxArr['peer_name'] = 'us.php.net'; $ctx = stream_context_create(['ssl' => $ctxArr]); $client = stream_socket_client("tls://127.0.0.1:$port", $errno, $errstr, 1, $flags, $ctx); $cert = stream_context_get_options($ctx)['ssl']['peer_certificate']; var_dump(openssl_x509_parse($cert)['subject']['CN']);
在测试的同时,应用 tcpdump 进行抓包
<code class="bash">tcpdump -i lo0 port 9501 -w sni.pcap
申请胜利后,客户端会输入对应的三个 Hostname
<code class="bash">$ php swoole.php string(10) "cs.php.net" string(10) "uk.php.net" string(10) "us.php.net"
而后应用 Wireshark 来剖析一下抓到的包,通过ssl.handshake
来过滤出想要的报文
剖析报文发现 server_name 的扩大字段只存在于 Client Hello 这个过程中
接着应用ssl.handshake.extensions_server_name
进行过滤,提取出蕴含 SNI 协定的 Client Hello 报文
就能够看到 SNI 扩大字段:
<code class="txt">Extension: server_name (len=15) Type: server_name (0) Length: 15 Server Name Indication extension Server Name list length: 13 Server Name Type: host_name (0) Server Name length: 10 Server Name: cs.php.net
这里指定了该 TLS 握手的指标域名为 cs.php.net
。
通过 SNI,领有多域名的服务器就能够失常建设 TLS 连贯了。
上面是残缺的测试代码:
<code class="php"><?php use Swoole\Http\Request; use Swoole\Http\Response; use Swoole\Http\Server; use Swoole\Process\Manager; use Swoole\Process\Pool; define('SSL_FILE_DIR', __DIR__ . '/ssl_certs'); $pm = new Manager(); $pm->add(function (Pool $pool, int $workerId) { $http = new Server('127.0.0.1', 9501, SWOOLE_BASE, SWOOLE_SOCK_TCP | SWOOLE_SSL); $http->set([ 'log_file' => '/dev/null', 'ssl_cert_file' => SSL_FILE_DIR . '/server.crt', 'ssl_key_file' => SSL_FILE_DIR . '/server.key', 'ssl_protocols' => SWOOLE_SSL_TLSv1_2 | SWOOLE_SSL_TLSv1_3 | SWOOLE_SSL_TLSv1_1 | SWOOLE_SSL_SSLv2, 'ssl_sni_certs' => [ 'cs.php.net' => [ 'ssl_cert_file' => SSL_FILE_DIR . '/sni_server_cs_cert.pem', 'ssl_key_file' => SSL_FILE_DIR . '/sni_server_cs_key.pem' ], 'uk.php.net' => [ 'ssl_cert_file' => SSL_FILE_DIR . '/sni_server_uk_cert.pem', 'ssl_key_file' => SSL_FILE_DIR . '/sni_server_uk_key.pem' ], 'us.php.net' => [ 'ssl_cert_file' => SSL_FILE_DIR . '/sni_server_us_cert.pem', 'ssl_key_file' => SSL_FILE_DIR . '/sni_server_us_key.pem', ], ] ]); $http->on('request', function (Request $request, Response $response) { $response->end('Hello Swoole'); }); $http->start(); }); $pm->add(function (Pool $pool, int $workerId) { $flags = STREAM_CLIENT_CONNECT; $port = 9501; $ctxArr = [ 'cafile' => SSL_FILE_DIR . '/sni_server_ca.pem', 'capture_peer_cert' => true, 'verify_peer' => false, ]; $ctxArr['peer_name'] = 'cs.php.net'; $ctx = stream_context_create(['ssl' => $ctxArr]); $client = stream_socket_client("tls://127.0.0.1:$port", $errno, $errstr, 1, $flags, $ctx); $cert = stream_context_get_options($ctx)['ssl']['peer_certificate']; var_dump(openssl_x509_parse($cert)['subject']['CN']); $ctxArr['peer_name'] = 'uk.php.net'; $ctx = stream_context_create(['ssl' => $ctxArr]); $client = stream_socket_client("tls://127.0.0.1:$port", $errno, $errstr, 1, $flags, $ctx); $cert = stream_context_get_options($ctx)['ssl']['peer_certificate']; var_dump(openssl_x509_parse($cert)['subject']['CN']); $ctxArr['peer_name'] = 'us.php.net'; $ctx = stream_context_create(['ssl' => $ctxArr]); $client = stream_socket_client("tls://127.0.0.1:$port", $errno, $errstr, 1, $flags, $ctx); $cert = stream_context_get_options($ctx)['ssl']['peer_certificate']; var_dump(openssl_x509_parse($cert)['subject']['CN']); $pool->shutdown(); }); $pm->start();