From a5fcea2d2f790aa90b6e996d411ae2cf8db55186 Mon Sep 17 00:00:00 2001 From: Alex Henrie Date: Tue, 13 Feb 2024 23:26:31 -0700 Subject: net: ipv6/addrconf: introduce a regen_min_advance sysctl In RFC 8981, REGEN_ADVANCE cannot be less than 2 seconds, and the RFC does not permit the creation of temporary addresses with lifetimes shorter than that: > When processing a Router Advertisement with a > Prefix Information option carrying a prefix for the purposes of > address autoconfiguration (i.e., the A bit is set), the host MUST > perform the following steps: > 5. A temporary address is created only if this calculated preferred > lifetime is greater than REGEN_ADVANCE time units. However, some users want to change their IPv6 address as frequently as possible regardless of the RFC's arbitrary minimum lifetime. For the benefit of those users, add a regen_min_advance sysctl parameter that can be set to below or above 2 seconds. Link: https://datatracker.ietf.org/doc/html/rfc8981 Signed-off-by: Alex Henrie Reviewed-by: David Ahern Signed-off-by: Paolo Abeni --- Documentation/networking/ip-sysctl.rst | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'Documentation/networking') diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index 458305931345..407d917d1a36 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -2535,6 +2535,16 @@ max_desync_factor - INTEGER Default: 600 +regen_min_advance - INTEGER + How far in advance (in seconds), at minimum, to create a new temporary + address before the current one is deprecated. This value is added to + the amount of time that may be required for duplicate address detection + to determine when to create a new address. Linux permits setting this + value to less than the default of 2 seconds, but a value less than 2 + does not conform to RFC 8981. + + Default: 2 + regen_max_retry - INTEGER Number of attempts before give up attempting to generate valid temporary addresses. -- cgit v1.2.3