错误：“raw.githubusercontent.com”的证书不受信任

Question

我正在尝试使用 wget 通过远程服务器 (ssh) 从 github 检索一些文件，这是我得到的：

$ wget  https://raw.githubusercontent.com/aseemk/seadragon-ajax/master/seadragon-min.js
--2014-11-26 09:30:14--  https://raw.githubusercontent.com/aseemk/seadragon-ajax/master/seadragon-min.js
Resolving raw.githubusercontent.com (raw.githubusercontent.com)... 185.31.19.133
Connecting to raw.githubusercontent.com (raw.githubusercontent.com)|185.31.19.133|:443... connected.
ERROR: The certificate of `raw.githubusercontent.com' is not trusted.
ERROR: The certificate of `raw.githubusercontent.com' hasn't got a known issuer.

卷曲也是如此：

$ curl -o bla  https://raw.githubusercontent.com/aseemk/seadragon-ajax/master/seadragon-min.js
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0curl: (60) SSL certificate problem: unable to get local issuer certificate
More details here: http://curl.haxx.se/docs/sslcerts.html

curl performs SSL certificate verification by default, using a "bundle"
 of Certificate Authority (CA) public keys (CA certs). If the default
 bundle file isn't adequate, you can specify an alternate file
 using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
 the bundle, the certificate verification probably failed due to a
 problem with the certificate (it might be expired, or the name might
 not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
 the -k (or --insecure) option.

使用 wget 选项：--no-check-certificate 似乎是一个 hack，我会遗漏什么？

Answer 1

解决方法很简单，从我的 debian 系统简单安装：

$ sudo apt-get install ca-certificates

Answer 2

我在 raspbian 上遇到了这个问题，修复了它：

sudo apt-get install ssl-cert