Ejemplo de HTTP CSP: script-src-elem

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El HTTP Content-Security-Policy (CSP) script-src-elem directiva especifica fuentes válidas para JavaScript



Content-Security-Policy: script-src-elem ;
Content-Security-Policy: script-src-elem  ;

script-src-elem can be used in conjunction with script-src:
Content-Security-Policy: script-src ;
Content-Security-Policy: script-src-elem ;

Sources
can be one of the following:



Internet hosts by name or IP address, as well as an optional URL scheme and/or port number. The site's address may include an optional leading wildcard (the asterisk character, '*'), and you may use a wildcard (again, '*') as the port number, indicating that all legal ports are valid for the source.
 Examples: 

http://*.example.com: Matches all attempts to load from any subdomain of example.com using the http: URL scheme.
mail.example.com:443: Matches all attempts to access port 443 on mail.example.com.
https://store.example.com: Matches all attempts to access store.example.com using https:.
*.example.com: Matches all attempts to load from any subdomain of example.com using the current protocol.



A scheme such as http: or https:. The colon is required. Unlike other values below, single quotes shouldn't be used. You can also specify data schemes (not recommended). 

data: Allows data: URIs to be used as a content source. This is insecure; an attacker can also inject arbitrary data: URIs. Use this sparingly and definitely not for scripts.
mediastream: Allows mediastream: URIs to be used as a content source.
blob: Allows blob: URIs to be used as a content source.
filesystem: Allows filesystem: URIs to be used as a content source.


'self'
Refers to the origin from which the protected document is being served, including the same URL scheme and port number. You must include the single quotes. Some browsers specifically exclude blob and filesystem from source directives. Sites needing to allow these content types can specify them using the Data attribute.
'unsafe-eval'
Allows the use of eval() and similar methods for creating code from strings. You must include the single quotes.
'unsafe-hashes'
Allows enabling specific inline event handlers. If you only need to allow inline event handlers and not inline