Name

loc_network_get_asn, loc_network_set_asn, loc_network_get_country_code, loc_network_set_country_code, loc_network_matches_country_code, loc_network_has_flag, loc_network_set_flag - What is known about a network

Synopsis

#include <libloc/network.h>

enum loc_network_flags {
        LOC_NETWORK_FLAG_ANONYMOUS_PROXY    = (1 << 0), // A1
        LOC_NETWORK_FLAG_SATELLITE_PROVIDER = (1 << 1), // A2
        LOC_NETWORK_FLAG_ANYCAST            = (1 << 2), // A3
        LOC_NETWORK_FLAG_DROP               = (1 << 3), // XD
};

uint32_t loc_network_get_asn(struct loc_network* network);

int loc_network_set_asn(struct loc_network* network, uint32_t asn);

const char* loc_network_get_country_code(struct loc_network* network);

int loc_network_set_country_code(struct loc_network* network,
        const char* country_code);

int loc_network_matches_country_code(struct loc_network* network,
        const char* country_code);

int loc_network_has_flag(struct loc_network* network, uint32_t flag);

int loc_network_set_flag(struct loc_network* network, uint32_t flag);

Description

The database knows for each network which country it is in, which Autonomous System announces it, and whether it is special in any way.

loc_network_get_asn() returns the number of the Autonomous System, or zero if there is none. More about the Autonomous System can be found with loc_database_get_as(3). loc_network_set_asn() sets it, and zero removes it.

loc_network_get_country_code() returns the code of the country (ISO 3166-1 alpha-2), for example DE, or an empty string if the country is not known. More about the country can be found with loc_database_get_country(3). loc_network_set_country_code() sets it, and NULL or an empty string remove it.

loc_network_has_flag() checks whether the network has any of the flags in flag. loc_network_set_flag() adds them. The flags are:

LOC_NETWORK_FLAG_ANONYMOUS_PROXY

The network hides where its users are, like a VPN or an open proxy.

LOC_NETWORK_FLAG_SATELLITE_PROVIDER

The network is used by a satellite provider, whose users can be anywhere.

LOC_NETWORK_FLAG_ANYCAST

The same network is being announced in many places, so that it cannot be said where an address is.

LOC_NETWORK_FLAG_DROP

The network has been hijacked, or it is being used by spammers or other criminals, for example because it is on the DROP lists of Spamhaus. It is a good idea to drop anything coming from it.

These have been given the codes A1, A2, A3 and XD, which are being used like country codes, for example by the location(1) command.

loc_network_matches_country_code() checks whether the network is in the country with the code country_code. If country_code is one of the codes above, it checks whether the network has that flag instead.

Return Value

loc_network_set_country_code() returns zero on success, and -EINVAL if country_code is not a valid country code (see loc_country_new(3)). loc_network_set_asn() and loc_network_set_flag() always return zero.

loc_network_has_flag() returns a value that is not zero if the network has any of the flags.

loc_network_matches_country_code() returns 1 if the network matches, zero if it does not, and -EINVAL if country_code is not a country code at all.

Example

const char* country_code = loc_network_get_country_code(network);

if (loc_network_has_flag(network, LOC_NETWORK_FLAG_DROP))
        printf("%s should be dropped\n", loc_network_str(network));

else if (*country_code)
        printf("%s is in %s\n", loc_network_str(network), country_code);

See Also

libloc(3), loc_network_new(3), loc_database_lookup(3)

Authors

Michael Tremer