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Diffstat (limited to 'oslo_utils/netutils.py')
| -rw-r--r-- | oslo_utils/netutils.py | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/oslo_utils/netutils.py b/oslo_utils/netutils.py index 26e16dc..af06a43 100644 --- a/oslo_utils/netutils.py +++ b/oslo_utils/netutils.py @@ -193,6 +193,35 @@ def get_ipv6_addr_by_EUI64(prefix, mac): 'EUI-64: %s') % prefix) +def get_mac_addr_by_ipv6(ipv6, dialect=netaddr.mac_unix_expanded): + """Extract MAC address from interface identifier based IPv6 address. + + For example from link-local addresses (fe80::/10) generated from MAC. + + :param ipv6: An interface identifier (i.e. mostly MAC) based IPv6 + address as a netaddr.IPAddress() object. + :param dialect: The netaddr dialect of the the object returned. + Defaults to netaddr.mac_unix_expanded. + :returns: A MAC address as a netaddr.EUI() object. + + See also: + * https://tools.ietf.org/html/rfc4291#appendix-A + * https://tools.ietf.org/html/rfc4291#section-2.5.6 + + .. versionadded:: 4.3.0 + """ + return netaddr.EUI(int( + # out of the lowest 8 bytes (byte positions 8-1) + # delete the middle 2 bytes (5-4, 0xff_fe) + # by shifting the highest 3 bytes to the right by 2 bytes (8-6 -> 6-4) + (((ipv6 & 0xff_ff_ff_00_00_00_00_00) >> 16) + + # adding the lowest 3 bytes as they are (3-1) + (ipv6 & 0xff_ff_ff)) ^ + # then invert the universal/local bit + 0x02_00_00_00_00_00), + dialect=dialect) + + def is_ipv6_enabled(): """Check if IPv6 support is enabled on the platform. |