can not proxy https request

[simonisacoder]

proxy http request, normal

but proxy https request ,eg
curl --insecure -v -x 'https://100.95.7.219:10115' https://www.google.com

• About to connect() to proxy 100.95.7.219 port 10115 (#0)
• Trying 100.95.7.219... connected
• Connected to 100.95.7.219 (100.95.7.219) port 10115 (#0)
• Establish HTTP proxy tunnel to www.baidu.com:443

CONNECT www.baidu.com:443 HTTP/1.1
Host: www.baidu.com:443
User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.13.1.0 zlib/1.2.3 libidn/1.18 libssh2/1.2.2
Proxy-Connection: Keep-Alive

• Proxy CONNECT aborted
• Closing connection #0
  curl: (56) Proxy CONNECT aborted

it seems that the proxy server can not establish connect with the target server
i don't know wherther it is caused by ssl certificate
but i can curl https://google.com in the proxy server ,
so i don't know what's the problem