mac os

$ rvm osx-ssl-certs update
  • Get the CURL Certificate Authority (CA) bundle. You can do this with:
$ sudo port install curl-ca-bundle [if you are using MacPorts]
  • Execute the ruby code that is trying to verify the SSL certification:
$ SSL_CERT_FILE=/opt/local/etc/certs/cacert.pem
  • gem 安装没有问题，但 bundle 安装报错，可以尝试更新 bundle

gem install bundle

Windows

$ gem install compass
// SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed
  • 下载 http://curl.haxx.se/ca/cacert.pem 文件到本地，路径为 C:\Ruby23-x64\cacert.pem
  • 新建系统环境变量 SSL_CERT_FILE ， 值为 C:\Ruby23-x64\cacert.pem
  • 重新打开命令行工具

参考

作者：bigfact