[libvirt] nwfilter: Also pick IP address from a DHCP ACK message

Stefan Berger stefanb at us.ibm.com
Thu Apr 29 13:22:04 UTC 2010

The local DHCP server on virtbr0 sends DHCP ACK messages when a VM is
started and requests an IP address while the initial DHCP lease on the
VM's MAC address hasn't expired. So, also pick the IP address of the VM
if that type of message is seen.
Thanks to Gerhard Stenzel for providing a test case for this.

Signed-off-by: Stefan Berger <stefanb at us.ibm.com>

Index: libvirt-acl/src/nwfilter/nwfilter_learnipaddr.c
--- libvirt-acl.orig/src/nwfilter/nwfilter_learnipaddr.c
+++ libvirt-acl/src/nwfilter/nwfilter_learnipaddr.c
@@ -98,6 +98,7 @@ struct dhcp {
+#define DHCP_MSGT_DHCPACK   5
 struct ether_vlan_header
@@ -347,6 +348,7 @@ procDHCPOpts(struct dhcp *dhcp, int dhcp
             if (dhcp_opts_len >= 3) {
                 uint8_t *val = (uint8_t *)&dhcpopt->value;
                 switch (*val) {
+                case DHCP_MSGT_DHCPACK:
                 case DHCP_MSGT_DHCPOFFER:
                     *vmaddr = dhcp->yiaddr;
                     *howDetected = DETECT_DHCP;

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