key_id
The 'key' directive specifies the cryptographic key used to sign the secure tokens generated by the NGINX Secure Token Module for CDN integrations.
Description
The 'key' directive in the NGINX Secure Token Module is crucial for generating secure tokens used for content delivery in CDN environments such as Akamai and Amazon CloudFront. This directive accepts a single argument, which should be a hexadecimal string representing the cryptographic key. The security and validity of the tokens that are created depend significantly on this key, as it is combined with the token parameters to produce a hashed HMAC signature using the SHA-256 hashing algorithm. The inclusion of this key in the configuration enables NGINX to create unique tokens that encrypt the URL or data bound for delivery, thereby restricting unauthorized access to the content defined by the generated tokens.
In operation, this directive is often used in conjunction with other related directives such as 'acl', which specifies access control lists for token validation, and 'param_name', which dictates the name of the query string parameter that will contain the generated token. When configured appropriately, NGINX will manage token generation dynamically, ensuring that the commercial content delivered through the CDN remains protected and meets the access policies set by the configurations. This ensures not only access management but also enhances the security posture against token tampering or unauthorized usage of content.
Config Example
secure_token_akamai {
key 1234567890abcdef1234567890abcdef; // Example key as a hex string
acl "allow all";
param_name "token";
start 0;
end 3600;
}Ensure the key is a valid hexadecimal string; otherwise, token generation will fail.
Be cautious with key exposure; treat the key like a password and avoid logging it.
Regenerate and manage keys periodically to enhance security practices.