pm_Checker:: ip_address_and_mask Method

Checks whether the specified IP address presents the expected type of IP address (non-masked IP address, masked IP address, masked IP range, etc.).

Syntax

public static function ip_address_and_mask ($ip_address, $ip_mask, $valid)

Parameters

ip_address

      A string value that specifies the IP address used to specify a valid subnet.

ip_mask

      A string value that specifies the IP mask used to specify a valid subnet.

valid

      A string value that specifies the validation rule to apply. Is set to IP_ADDRESS_ANY by default. The following validation rules are available:

• IP_ADDRESS_ANY allows the use of all rules available.
• IP_ADDRESS_BLOCK checks whether the IP address presents an address block (a group of network addresses) rather than a certain address.
• IP_ADDRESS_NETMASK checks whether the given IP address is an individual IP address with a mask.
• IP_ADDRESS selects the rule that checks whether the given IP mask specifies an individual IP address.

Returns

A boolean which is true if the specified IP address and IP mask are not 0.0.0.0 and the rule applied to them succeeds. Otherwise returns false.

Remarks

This function applies the selected validation rule(s) to the combination of the IP address and IP mask to check whether the IP address really belongs to the expected type (a non-masked IP address, a masked IP address, an IP range, etc.).

• The validation rules work as follows:
• IP_ADDRESS_BLOCK checks whether the IP address specifies a group of IP addresses (i.e. whether the IP address presents an address block). This rule requires the use of a masked IP address format, and the requirement is that the host bits are set to '0'. E.g. 123.123.0.0/16 is a range of addresses, but 123.123.0.1/16 is a particular IP address in a class B network.
• IP_ADDRESS_NETMASK checks whether the IP address is an individual masked IP address. The rule succeeds if the IP mask specifies the entire IP address, e.g. 123.123.123.1/32 or 123.123.123.1/255.255.255.255. The rule fails if the IP address has '0' bits in its host part, e.g. 123.123.0.0/16, or if it has all '1' bits in the host part (a broadcast address), e.g. 123.123.123.255/255.255.255.0.
• IP_ADDRESS checks whether the IP address in focus is a non-masked individual IP address. E.g. 123.123.123.123.
• IP_ADDRESS_ANY indicates to the function that all the rules should be applied to the IP address one after another until any of them succeeds. If none of the above rules succeeds, this rule also fails.