Yes, you can definitely use Curl to make requests to a website with SSL. The SSL (Secure Sockets Layer) and its successor, TLS (Transport Layer Security), are protocols for establishing authenticated and encrypted links between networked computers. It's widely used to secure web browsing, email, and other communications.
Curl, a command-line tool for getting or sending data using URL syntax, natively supports SSL certificates and HTTPS protocol. However, this can be problematic if the SSL certificate of the site you're trying to access is self-signed or not trusted. By default, Curl will refuse to connect to an HTTPS site that uses an untrusted or self-signed certificate.
To make Curl ignore certificate errors, you can use the -k or --insecure option:
curl -k https://example.com
This tells Curl to proceed with the operation even for server connections otherwise considered insecure. The server connection is verified by making sure the server's certificate contains the right name and verifies successfully using the cert store.
However, using -k or --insecure is generally not recommended as it makes the connection vulnerable to man-in-the-middle attacks. A better approach is to add the certificate to the system's list of trusted certificates. For this, you might need to download the certificate and add it to your system's certificate store.
Here's an example of how to do this:
- Get the certificate:
echo -n | openssl s_client -connect HOST:PORTNUMBER \
| sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' > /tmp/example.cert
- Once you have the certificate, you can use it with Curl:
curl --cacert /tmp/example.cert https://example.com
Remember to replace HOST:PORTNUMBER with your actual host and port number, and example.com with your actual URL.
