Intelligently parse IPv4/IPv6 addresses, CIDRs, ranges, and wildcard matches to attempt return a valid list of IP addresses.
The cidrize() function does all the work trying to parse IP addresses correctly.
Supported input formats¶
Input is very flexible and can be of any of the following formats:
192.0.2.18 18.104.22.168/26 192.0.2.80-192.0.2.85 192.0.2.170-175 192.0.2.8[0-5] 192.0.2.
Hyphenated ranges do not need to form a CIDR block but the starting number must be of lower value than the end. The netaddr module does most of the heavy lifting for us here.
Network mask (e.g. 192.0.2.0 255.255.255.0) and host mask (aka reverse mask, 192.0.2.0 0.0.0.255) notation are not accepted at this time.
The cidrize function returns a list of consolidated netaddr.IPNetwork objects. By default parsing exceptions will raise a CidrizeError (with default argument of modular=True). You may pass modular=False to cause exceptions to be stripped and the error text will be returned as a list. This is intended for use with scripts or APIs where receiving exceptions would not be preferred.
The module may also be run as a script for debugging purposes.
Fire up your trusty old Python interpreter and follow along!
>>> from cidrize import cidrize
>>> cidrize("22.214.171.124") [IPNetwork('126.96.36.199/32')]
Hyphenated range (default, strict=False)¶
>>> cidrize("188.8.131.52-184.108.40.206") [IPNetwork('220.127.116.11/25')]
Hyphenated range strict (strict=True)¶
>>> cidrize("18.104.22.168-22.214.171.124", strict=True) [IPNetwork('126.96.36.199/29'), IPNetwork('188.8.131.52/28'), IPNetwork('184.108.40.206/27'), IPNetwork('220.127.116.11/28'), IPNetwork('18.104.22.168/32')]
You may provide wildcards using asterisks. This is limited to the 4th and final octet only:
>>> cidrize("15.63.148.*") [IPNetwork('22.214.171.124/24')]
>>> cidrize("126.96.36.199[40-99]") [IPNetwork('188.8.131.52/30'), IPNetwork('184.108.40.206/28'), IPNetwork('220.127.116.11/27'), IPNetwork('18.104.22.168/29')]
Bad CIDR prefixes are rejected outright:
>>> cidrize("22.214.171.124/40") Traceback (most recent call last): File "<stdin>", line 1, in <module> File "cidrize.py", line 145, in cidrize raise CidrizeError(err) cidrize.CidrizeError: CIDR prefix /40 out of range for IPv4!
Ranges must always start from lower to upper bound, or this happens:
>>> cidrize("126.96.36.199-0") Traceback (most recent call last): File "<stdin>", line 1, in <module> File "cidrize.py", line 145, in cidrize raise CidrizeError(err) cidrize.CidrizeError: lower bound IP greater than upper bound!
The cidrize package also comes with the cidr command, which has two basic operations.
% cidr 188.8.131.52/30 184.108.40.206/30
% cidr -v 220.127.116.11/30 Spanning CIDR: 18.104.22.168/30 Block Start/Network: 22.214.171.124 1st host: 126.96.36.199 Gateway: 188.8.131.52 Block End/Broadcast: 184.108.40.206 DQ Mask: 255.255.255.252 Cisco ACL Mask: 0.0.0.3 # of hosts: 2 Explicit CIDR blocks: 220.127.116.11/30
And that’s that!