To start with, let us see a simple example with detailed steps.
Now we will see how to generate hash using SHA-2 hash code (SHA224, SHA256, SHA384, SHA512) algorithms in Python.
You can also modify the generated MAC addresses by removing bytes. Earlier we have seen a briefing about hash codes in Python and about hash codes using SHA1 algorithm. bytes b'\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f' > # make a UUID from a 16-byte string > uuid. You can use this program to generate multiple MAC addresses and then use them in the tests. I find it strange to treat it as a conglomerate of 5 8 bit and one 6 bit number.UUID ( '' ) > # convert a UUID to a string of hex digits in standard form > str ( x ) '00010203-0405-0607-0809-0a0b0c0d0e0f' > # get the raw 16 bytes of the UUID > x. Make sure you take care of both the MAC-S and MAC-L registries! ImplementationĪn EUI-48 is a 48 bit number. Therefore, your API should provide for passing in a OUI to generate an addresses for. It really only makes sense to generate a UAA within an OUI you own. I would choose the parameters such that they are "off-by-default" ( False) and ca be "turned on" by the caller: def random_eui48(*, multicast: bool = False, universal: bool = False) -> str: So, I would very much prefer to make LAAs the default. At most, you should randomly generate addresses within an OUI you own. In fact, I find it highly dubious to randomly generate UAAs at all. However, I disagree with making universally administered addresses the default. It is probably what users will usually need more often. I agree with the choice of making Unicast the default.
I would make them keyword-only arguments so that the caller is always forced to name them: def random_eui48(*, unicast: bool = True, universal: bool = True) -> str: Having two boolean parameters can lead to confusion.
So, your function should probably be named random_eui48 instead. For example, FireWire MAC addresses are EUI-64. It is also imprecise, since not all MAC addresses are EUI-48 addresses. These names should only be used as an obsolete label for EUI-48. The IEEE strongly discourages use of the name MAC or MAC-48. Speed isn't a huge concern, but I'm curious if there's a cleaner way that I'm missing.ĭef random_mac(unicast: bool = True, universal: bool = True) -> str: Attaching the first octet to the rest is suboptimal as well. macgen.py 00:16:3e:20:b0:11 /usr/bin/python macgen.py script to generate a MAC address for guests on Xen import random def randomMAC(): mac 0x00.Is treating a boolean value as a number during bitwise operation idiomatic? Is it clear as I have it now?.The numbers kind of sit on a border of self-explanatory and magic, so I decided to name them to be safe. The number constants are bugging me too.I tried explicitly setting the bits, but the code to decide between |, and & and ~ got messier than what I have now, so I went with this way.
Is there a better approach? It feels hacky generating it as two pieces then adding them together.It's not a lot of code, but I'd like a few things reviewed: These examples are extracted from open source projects. It works, but it's ugly and looks suboptimal. 36 Python code examples are found related to get mac address. The LSB of the first octet indicates uni/multicast, and the second LSB of the octet indicates universal/local, so these bits can't be random.Īfter playing around with a few failed ideas (generating all random bits, then "fixing" the two bits later), I finally decided to generate a random number between 0 and 63 inclusive, left shift it twice, than add the two bits on after. This caused me headaches though because I'm still not great at dealing with bits. I decided to allow the user to pick if it's unicast/multicast and universally/locally administered even though I'll only need unicast/universal. > random_mac(unicast=True, universal=False) > random_mac(unicast=False, universal=True) I need the ability to generate random MAC addresses, so I wrote up a little function that does that: > random_mac()