Add python script for GeoIP2 database lookup.

geoip-lookup.py

@@ -0,0 +1,96 @@
+#!/usr/bin/python3.8
+
+import getopt
+import sys
+
+try:
+    import geoip2.database
+except ImportError:
+    print(
+        "Required module geoip2.database not found. On Gentoo Linux, please install dev-python/geoip2 from the 'fritteli' overlay.",
+        file=sys.stderr)
+    exit(1)
+
+
+class LookupException(Exception):
+    """
+    General Exception class that is raised if anything goes wrong.
+    """
+    pass
+
+
+def get_county_code(ipaddress, dbfile):
+    """
+    Determine the country code that the given ipaddress comes from.
+    :param ipaddress: The IP address to look up
+    :param dbfile: The path to the GeoIP2/GeoLite2 database file (Country or City database)
+    :return: The ISO country code (2 letters)
+    """
+    if not ipaddress:
+        raise LookupException("No address given")
+    if not dbfile:
+        raise LookupException("No db file given")
+
+    reader = None
+    try:
+        reader = geoip2.database.Reader(dbfile)
+        dbtype = reader.metadata().database_type
+        country = None
+        if dbtype == 'GeoLite2-City' or dbtype == 'GeoIP2-City':
+            country = reader.city(ipaddress).country
+        elif dbfile == 'GeoLite2-Country' or dbtype == 'GeoIP2-Country':
+            country = reader.country(ipaddress).country
+        # ASN is not supported
+        # elif dbfile == 'GeoLite2-ASN' or dbtype == 'GeoIP2-ASN':
+
+        if not country:
+            raise LookupException("Unsupported DB type: " + dbtype)
+
+        return country.iso_code
+    finally:
+        if reader:
+            reader.close()
+
+
+def parse_command_line(argv):
+    """
+    Parse the command line. First, the database file must be specified ("-f /path/to/db/file.mmdb"), then the IP address
+    to look up
+    :param argv:
+    :return:
+    """
+    dbfile = None
+    try:
+        opts, args = getopt.getopt(argv, "f:")
+    except getopt.GetoptError as e:
+        raise LookupException("Error parsing command line") from e
+
+    for opt, arg in opts:
+        if opt == "-f":
+            dbfile = arg
+        else:
+            raise LookupException("Unknown command line argument")
+
+    if len(args) == 0:
+        raise LookupException("No address given on command line")
+    return dbfile, args[0]
+
+
+def main(argv):
+    """
+    Read the database file and the IP address from the command line and print the corresponding ISO country code on
+    stdout.
+    :param argv: Format: "-f /path/to/database.mmdb ip.v4.add.ress"
+    :return:
+    """
+    (dbfile, ipaddress) = parse_command_line(argv)
+    code = get_county_code(ipaddress, dbfile)
+    print(code)
+
+
+if __name__ == '__main__':
+    try:
+        main(sys.argv[1:])
+    except BaseException as e:
+        print("Usage: geoip-lookup.py -f /path/to/geoip2-database.mmdb 192.168.1.1", file=sys.stderr)
+        raise e