2:35 a.m.
From: Chen Hanxiao <chenhanxiao(a)gmail.com>
introduce VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_ARP to get ip address
of VM from the output of /proc/net/arp
Signed-off-by: Chen Hanxiao <chenhanxiao(a)gmail.com>
---
v3:
add docs in virDomainInterfaceAddresses
remove error label
show network interface which did not match the arp table
include/libvirt/libvirt-domain.h | 1 +
src/libvirt-domain.c | 7 +++
src/qemu/qemu_driver.c | 96 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 104 insertions(+)
diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index 4048acf38..38e2d9a3e 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -4665,6 +4665,7 @@ typedef virMemoryParameter *virMemoryParameterPtr;
typedef enum {
VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_LEASE = 0, /* Parse DHCP lease file */
VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_AGENT = 1, /* Query qemu guest agent */
+ VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_ARP = 2, /* Query ARP tables */
# ifdef VIR_ENUM_SENTINELS
VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_LAST
diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c
index eaec0979a..1ae83610d 100644
--- a/src/libvirt-domain.c
+++ b/src/libvirt-domain.c
@@ -11721,6 +11721,13 @@ virDomainFSInfoFree(virDomainFSInfoPtr info)
* To match such interface with the one from @dom XML use MAC address or IP
* range.
*
+ * If @source is VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_ARP, the /proc/net/arp
+ * will be check to obtain the interface addresses.
+ * As the arp cache did not refresh in time, the returned ip address
+ * may be unreachable.
+ * As the route config of the guest, the returned mac address
+ * may be duplicated.
+ *
* @ifaces->name and @ifaces->hwaddr are never NULL.
*
* The caller *must* free @ifaces when no longer needed. Usual use case
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index a203c9297..d0cb88053 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -70,6 +70,7 @@
#include "virnetdevopenvswitch.h"
#include "capabilities.h"
#include "viralloc.h"
+#include "virarptable.h"
#include "viruuid.h"
#include "domain_conf.h"
#include "domain_audit.h"
@@ -160,6 +161,9 @@ static int qemuGetDHCPInterfaces(virDomainPtr dom,
virDomainObjPtr vm,
virDomainInterfacePtr **ifaces);
+static int qemuARPGetInterfaces(virDomainObjPtr vm,
+ virDomainInterfacePtr **ifaces);
+
static virQEMUDriverPtr qemu_driver;
@@ -20384,6 +20388,10 @@ qemuDomainInterfaceAddresses(virDomainPtr dom,
break;
+ case VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_ARP:
+ ret = qemuARPGetInterfaces(vm, ifaces);
+ break;
+
default:
virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED,
_("Unknown IP address data source %d"),
@@ -20494,6 +20502,94 @@ qemuGetDHCPInterfaces(virDomainPtr dom,
}
+static int
+qemuARPGetInterfaces(virDomainObjPtr vm,
+ virDomainInterfacePtr **ifaces)
+{
+ size_t i, j;
+ size_t ifaces_count = 0;
+ int ret = -1;
+ char macaddr[VIR_MAC_STRING_BUFLEN];
+ virDomainInterfacePtr *ifaces_ret = NULL;
+ virDomainInterfacePtr iface = NULL;
+ virArpTablePtr table;
+ int got_one = 0;
+
+ table = virArpTableGet();
+ if (!table)
+ goto cleanup;
+
+ for (i = 0; i < vm->def->nnets; i++) {
+ got_one = 0;
+ if (vm->def->nets[i]->type != VIR_DOMAIN_NET_TYPE_NETWORK)
+ continue;
+
+ virMacAddrFormat(&(vm->def->nets[i]->mac), macaddr);
+ virArpTableEntry entry;
+ for (j = 0; j < table->n; j++) {
+ entry = table->t[j];
+ if (STREQ(entry.mac, macaddr)) {
+ got_one = 1;
+ if (VIR_EXPAND_N(ifaces_ret, ifaces_count, 1) < 0)
+ goto cleanup;
+ if (VIR_ALLOC(ifaces_ret[ifaces_count - 1]) < 0)
+ goto cleanup;
+
+ iface = ifaces_ret[ifaces_count - 1];
+ iface->naddrs = 1;
+ if (VIR_ALLOC_N(iface->addrs, iface->naddrs) < 0)
+ goto cleanup;
+
+ if (VIR_STRDUP(iface->name, vm->def->nets[i]->ifname) <
0)
+ goto cleanup;
+
+ if (VIR_STRDUP(iface->hwaddr, macaddr) < 0)
+ goto cleanup;
+
+ if (VIR_STRDUP(iface->addrs->addr, entry.ipaddr) < 0)
+ goto cleanup;
+ }
+ }
+
+ if (got_one == 0) {
+ if (VIR_EXPAND_N(ifaces_ret, ifaces_count, 1) < 0)
+ goto cleanup;
+ if (VIR_ALLOC(ifaces_ret[ifaces_count - 1]) < 0)
+ goto cleanup;
+
+ iface = ifaces_ret[ifaces_count - 1];
+ iface->naddrs = 1;
+ if (VIR_ALLOC_N(iface->addrs, iface->naddrs) < 0)
+ goto cleanup;
+
+ if (VIR_STRDUP(iface->name, "") < 0)
+ goto cleanup;
+
+ if (VIR_STRDUP(iface->hwaddr, macaddr) < 0)
+ goto cleanup;
+
+ if (VIR_STRDUP(iface->addrs->addr, "") < 0)
+ goto cleanup;
+ }
+ }
+
+ *ifaces = ifaces_ret;
+ ifaces_ret = NULL;
+ ret = ifaces_count;
+
+ cleanup:
+ virArpTableFree(table);
+
+ if (ifaces_ret) {
+ for (i = 0; i < ifaces_count; i++)
+ virDomainInterfaceFree(ifaces_ret[i]);
+ }
+ VIR_FREE(ifaces_ret);
+
+ return ret;
+}
+
+
static int
qemuDomainSetUserPassword(virDomainPtr dom,
const char *user,
--
2.14.3