From 0698ff4184c3652d97c04e15ffac90d0b3aa3529 Mon Sep 17 00:00:00 2001 From: Jason Reeder Date: Fri, 31 Mar 2017 15:40:18 -0500 Subject: [PATCH] libsystemd-network: sd-ipv4ll: acquire new address after claimed address conflict If a conflict occurs on a claimed ipv4ll address, the device releases the address and then does not attempt to acquire a new ipv4ll address. According to RFC3927, releasing the address in this situation is correct. However, this should be followed by an attempt to configure a new ipv4ll address. This commit restarts the ipv4ll address acquisition state machine after releasing the conflicting address. From RFC3927 Section 2.5 conflict defense method (b): ... However, if this is not the first conflicting ARP packet the host has seen, and the time recorded for the previous conflicting ARP packet is recent, within DEFEND_INTERVAL seconds, then the host MUST immediately cease using this address and configure a new IPv4 Link-Local address as described above. ... Signed-off-by: Jason Reeder --- src/network/networkd-ipv4ll.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/src/network/networkd-ipv4ll.c b/src/network/networkd-ipv4ll.c index 7ba05dbec30..e2578a298b9 100644 --- a/src/network/networkd-ipv4ll.c +++ b/src/network/networkd-ipv4ll.c @@ -179,12 +179,22 @@ static void ipv4ll_handler(sd_ipv4ll *ll, int event, void *userdata) { switch(event) { case SD_IPV4LL_EVENT_STOP: + r = ipv4ll_address_lost(link); + if (r < 0) { + link_enter_failed(link); + return; + } + break; case SD_IPV4LL_EVENT_CONFLICT: r = ipv4ll_address_lost(link); if (r < 0) { link_enter_failed(link); return; } + + r = sd_ipv4ll_restart(ll); + if (r < 0) + log_link_warning(link, "Could not acquire IPv4 link-local address"); break; case SD_IPV4LL_EVENT_BIND: r = ipv4ll_address_claimed(ll, link); -- 2.47.3