Network Security Tools

Nikto’s Program Flow

At 200 lines of code the Nikto.pl file is relatively small. The following paragraphs briefly discuss what the program does on a macro level.

At the start of the program, you’ll notice a series of global variables. To avoid namespace collisions, plug-in developers shouldn’t use these variable names. Next, load_configs( ) parses the configuration file config.txt and initializes %CONFIG. Then the find_plugins( ) routine searches expected directories for the plug-in file, and sets appropriate values in %FILES. The nikto_core plug-in and LibWhisker are included with the require keyword, which makes all routines from LW.pm and nikto_core.plugin available to the rest of nikto.pl as well as to its plug-ins. The general_config() routine parses the command-line options and sets %CLI appropriately. Next, LibWhisker’s http_init_request( ) initializes LibWhisker’s %request with default values.

The proxy_setup( ) function sets the appropriate values in %request, depending upon the proxy settings in the configuration file. The open_output() function opens a file handle for writing program output, only if an output file was specified on the command line. Next, set_targets( ) populates %TARGETS with the hostname or IP address of the target, along with specified ports. The load_scan_items( ) function loads the vulnerability checks found from servers.db, scan_database.db, and user_scan_database.db (if the file exists) into global arrays.

Finally, the main loop for the vulnerability ...