Custom cPanel Module Errors Out in Latest cPanel

November 17, 2023 15:25

Which version is this? v116? If this is a bug it would be helpful to know when precisely this started, as I can look up the version's tag in git to try to see what code might have been responsible for this kind of change. Regardless, I can at least give you some context about where this is failing. Like 367 starts a perl eval
block which attempts to execute your module's custom function. The function itself is found and executed like so:


365     if ( my $function_cr = $function_cache{"Cpanel::API::${module}::$function"} ||= "Cpanel::API::${module}"->can($function) ) {
366         local $@;                                                              
367         eval {                                                                 
368             local $SIG{'__DIE__'};                                             
369             $result->status( scalar $function_cr->( $args, $result ) );        
370             1;                                                                 
371         } or do {                                                              
372             _handle_eval_fail( $result, $@ );                                  
373         };                                                                     
374     }

Since this code is inside an eval, It's hard to say without looking at your code what exactly is going wrong, but certainly if I had to guess, the subroutine you've defined which matches what we get with Cpanel::API::ExampleDevModule->can('test_function');
is perhaps returning something unexpected. Given you executed ExampleDevModule
yet your stacktrace shows StarshipDev
, I'd say that there's likely some shenanigans going on here with what this module is returning via UNIVERSAL::can
, which might explain why typeglobs are involved in this error. If you want your module to return a subroutine reference from another module, It's probably better to use the have Cpanel::API::ExampleDevModule::test_function
require that other module then return Cpanel::API::StarshipDev::test_function($args,$result);
instead of fiddling with the symbol table across namespaces in perl. Apologies in advance if I misunderstand what's happening here. Errors within an eval block are already frustrating enough to have to deal with at times. The "canonical" example for custom UAPI modules currently lives here:

0

Mind on the Net

November 17, 2023 18:26

Which version is this? v116? If this is a bug it would be helpful to know when precisely this started, as I can look up the version's tag in git to try to see what code might have been responsible for this kind of change.

This is moving from a 110.0.15 server to 114.0.12 server. The earlier one may have been broken recently with an upgrade too, not certain. I just know that it was working some months ago. [quote]Since this code is inside an eval, It's hard to say without looking at your code what exactly is going wrong, but certainly if I had to guess, the subroutine you've defined which matches what we get with Cpanel::API::ExampleDevModule->can('test_function');
is perhaps returning something unexpected.
Basically this:



package Cpanel::API::ExampleDevModule;

use strict;
use JSON::XS qw( decode_json );
use Data::Dumper qw(Dumper);

our $VERSION = '1.0';

# Cpanel Dependencies
use Cpanel                   ();
use Cpanel::API              ();
use Cpanel::Locale           ();
use Cpanel::Logger           ();
use Cpanel::LiveAPI          ();

# Globals
my $logger;
my $locale;

...........

sub test_function{
    # $Cpanel::CPDATA pulls data from /var/cpanel/users/user file
    my $user = $Cpanel::CPDATA{'USER'};

    my ( $args, $result ) = @_;

    # Build the results.
    my $success = "true";

    if ($success) {
        return 1;
    }
    else {
        return 0;
    }
}

[quote]Given you executed ExampleDevModule
yet your stacktrace shows StarshipDev
, I'd say that there's likely some shenanigans going on here.
That's because I edited the code to post it here, must have missed that edit. There is no mismatch in between module and function names in the code. [quote]The "canonical" example for custom UAPI modules currently lives here:

0

Mind on the Net

November 18, 2023 02:49

I started from scratch and I was able to call a new cpanel UAPI module, then do privilege escalation to a custom admin module and run a root owned php script with the executable bit on that was sitting in /root by using the admin module method below:

0

Custom cPanel Module Errors Out in Latest cPanel

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