HTTPS response page

[Jafar_Hussain]

Dears,

I have created one custom response page(including image) that is for application block and URL block.

example:- If someone wants to access a restricted URL or application the page should be displayed on the customer screen.

I can see, once I apply the custom response page in the URL block page and application block page. then access the HTTP traffic the page display was showing properly, however, while accessing the HTTPS site not able to get the response page.

I have applied the SSL forward proxy decryption. and the traffic decrypted correctly.

Can anyone help me to achieve this?

[nikoolayy1]

Have you checked this article  (read it carefully)?

https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA10g000000ClFKCA0

[Jafar_Hussain]

@nikoolayy1 

I believe this article for. to get the response page without SSL decryption. but in my case, the decryption already applied.

[nikoolayy1]

Have you tested with:

set deviceconfig setting ssl-decrypt url-proxy yes

I am wondering if this will work without fully decrypting the traffic. Also you have added the SSL Trust certficate to the client workstation ?

Also did you test with the default page if client sees the page?

[Jafar_Hussain]

@nikoolayy1 

yes, the certificate is installed in client machine.

I  checked the default page for HTTP and https that is working fine.

However, for the custom page, the only HTTP website showing the page. while accessing  HTTPS not able to get the custom response page.

[nikoolayy1]

Use tcpdump or Fiddler or HTTPWatch. Maybe the page is returned to the client but the web blowser does not like it for the ssl traffic as new blowsers have such protections (you may test with curl as it will not have such protection and it will display the response page ).

Can you share the custom page if you see that it is not send at all by the Firewall to workstation and just the workstation is not displaying?

[Jafar_Hussain]

@nikoolayy1 

I took the capture from the fiddler and found the below error:-

I Don't know why i am getting the connection refuse error. because this same is working with HTTP  as well.

[nikoolayy1]

Is it possible if your custom web page uses custom elements like images etc. not hosted on the Palo Alto firewall itself then the source server that actually hosts the content to be listening to only http on port 80 and not on https 443 ? Many new web blowsers will not agree the main web page that is using SSL to have elements that need plain text http as I see that the web blowser tries https to get an element and it fails but maybe the source server for that elements listens only on http and this is why for HTTP the page works.

Also it is possible for the source server url/ip address of that element that breaks the custom page to not be in the decryption rule of the Palo Alto decryption policy ?

Edit :

I also see you have CONNECT header, is there any proxy between the client and the Palo Alto and the source server of the element ? As the proxy will need to be checked as well if it blocks for some reason https elements of the custom page?

https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/CONNECT

[Jafar_Hussain]

@nikoolayy1 

There is no proxy.

[Chacko42]

Hi @Jafar_Hussain,

I would recommend to go back to the default page, to test, if the mechanism is still working.

For integrating images, you can use base64 encoded pictures inside an <img> tag.

With that you can slowly move forward, modify your page and see, when the page isn't shown further.