[libvirt] [PATCHv5 3/4] net-dhcp-leases: Private implementation inside network
Nehal J Wani
nehaljw.kkd1 at gmail.com
Mon Nov 25 21:06:00 UTC 2013
By querying the driver for the path of the custom leases file for the given
virtual network and parsing it to retrieve info.
src/network/bridge_driver.c:
* Implement networkGetDHCPLeases
* Implement networkGetDHCPLeasesForMAC
* Implement networkGetDHCPLeasesHelper
---
src/network/bridge_driver.c | 248 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 248 insertions(+)
diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
index 83dc931..1aedf86 100644
--- a/src/network/bridge_driver.c
+++ b/src/network/bridge_driver.c
@@ -109,6 +109,20 @@ static int networkPlugBandwidth(virNetworkObjPtr net,
virDomainNetDefPtr iface);
static int networkUnplugBandwidth(virNetworkObjPtr net,
virDomainNetDefPtr iface);
+/**
+ * VIR_NETWORK_DHCP_LEASE_FILE_SIZE_MAX:
+ *
+ * Macro providing the upper limit on the size of leases file
+ */
+#define VIR_NETWORK_DHCP_LEASE_FILE_SIZE_MAX 2097152
+
+/**
+ * VIR_NETWORK_DHCP_LEASE_FIELDS:
+ *
+ * Macro providing the maximum number of fields in an entry in
+ * the leases file
+ */
+#define VIR_NETWORK_DHCP_LEASE_FIELDS 6
static virNetworkDriverStatePtr driverState = NULL;
@@ -147,6 +161,16 @@ networkDnsmasqLeaseFileNameFunc networkDnsmasqLeaseFileName =
networkDnsmasqLeaseFileNameDefault;
static char *
+networkDnsmasqLeaseFileNameCustom(const char *bridge)
+{
+ char *leasefile;
+
+ ignore_value(virAsprintf(&leasefile, "%s/%s.status",
+ driverState->dnsmasqStateDir, bridge));
+ return leasefile;
+}
+
+static char *
networkDnsmasqConfigFileName(const char *netname)
{
char *conffile;
@@ -182,6 +206,7 @@ networkRemoveInactive(virNetworkDriverStatePtr driver,
virNetworkObjPtr net)
{
char *leasefile = NULL;
+ char *customleasefile = NULL;
char *radvdconfigfile = NULL;
char *configfile = NULL;
char *radvdpidbase = NULL;
@@ -200,6 +225,9 @@ networkRemoveInactive(virNetworkDriverStatePtr driver,
if (!(leasefile = networkDnsmasqLeaseFileName(def->name)))
goto cleanup;
+ if (!(customleasefile = networkDnsmasqLeaseFileNameCustom(def->bridge)))
+ goto cleanup;
+
if (!(radvdconfigfile = networkRadvdConfigFileName(def->name)))
goto cleanup;
@@ -216,6 +244,7 @@ networkRemoveInactive(virNetworkDriverStatePtr driver,
/* dnsmasq */
dnsmasqDelete(dctx);
unlink(leasefile);
+ unlink(customleasefile);
unlink(configfile);
/* radvd */
@@ -1058,6 +1087,9 @@ networkBuildDhcpDaemonCommandLine(virNetworkObjPtr network,
cmd = virCommandNew(dnsmasqCapsGetBinaryPath(caps));
virCommandAddArgFormat(cmd, "--conf-file=%s", configfile);
+
+ /* This helper is used to create cutom leases file for libvirt */
+ virCommandAddArgFormat(cmd, "--dhcp-script=%s", LIBEXECDIR "/libvirt_leaseshelper");
*cmdout = cmd;
ret = 0;
cleanup:
@@ -2991,6 +3023,220 @@ cleanup:
return ret;
}
+/* This function parses the leases file of dnsmasq.
+ *
+ * An example of custom leases file content:
+ *
+ * 1385245780 52:54:00:2f:ba:76 * 192.168.150.153 * *
+ * 1385245781 52:54:00:2f:ba:76 3127926 2001:db8:ca2:2:1::6c * 00:04:76:00:cf:ae:b3:0b:fc:cd:0e:22:2e:97:76:65:74:ec
+ * 1385245964 52:54:00:44:7c:d7 * 192.168.150.219 iiit-ad885e4aa1 01:52:54:00:44:7c:d7
+ * 1385245964 52:54:00:44:7c:d7 * 192.168.150.219 * 01:52:54:00:44:7c:d7
+ * 1385246016 52:54:00:5d:99:92 * 192.168.150.212 iiit-ad885e4aa1 01:52:54:00:5d:99:92
+ * 1385246041 52:54:00:3b:16:e0 * 192.168.150.207 * *
+ * 1385246081 52:54:00:db:dd:98 * 192.168.150.234 * *
+ * 1385246088 52:54:00:db:dd:98 14409112 2001:db8:ca2:2:1::6d * 00:04:76:00:cf:ae:b3:0b:fc:cd:0e:22:2e:97:76:65:74:ec
+ *
+ */
+static int
+networkGetDHCPLeasesHelper(virNetworkObjPtr obj,
+ const char *mac,
+ virNetworkDHCPLeasesPtr **leases)
+{
+ int rv = -1;
+ size_t i = 0;
+ size_t nleases = 0;
+ char *lease_file = NULL;
+ char **lease_fields = NULL;
+ char *lease_entries = NULL;
+ char *lease_entry = NULL;
+ virNetworkDHCPLeasesPtr *leases_ret = NULL;
+ virNetworkDHCPLeasesPtr lease = NULL;
+ int lease_file_len = 0;
+ bool ipv6 = false;
+ bool need_results = !!leases;
+
+ /* Retrieve custom leases file location */
+ lease_file = networkDnsmasqLeaseFileNameCustom(obj->def->bridge);
+
+ if ((lease_file_len = virFileReadAll(lease_file,
+ VIR_NETWORK_DHCP_LEASE_FILE_SIZE_MAX,
+ &lease_entries)) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("No leases available for network: %s"), obj->def->name);
+ goto cleanup;
+ }
+
+ lease_entry = lease_entries[0] == '\0' ? NULL : lease_entries;
+
+ while (lease_entry) {
+ int nfields = 0;
+ ipv6 = false;
+
+ char *eol = strchr(lease_entry, '\n');
+ *eol = '\0';
+
+ /* Split the lease line */
+ if (!(lease_fields = virStringSplit(lease_entry, " ",
+ VIR_NETWORK_DHCP_LEASE_FIELDS)))
+ goto error;
+
+ nfields = virStringListLength(lease_fields);
+
+ /* Forward lease_entry to the next lease */
+ lease_entry = strchr(lease_entry, '\0');
+ if (lease_entry - lease_entries + 1 < lease_file_len)
+ lease_entry++;
+ else
+ lease_entry = NULL;
+
+ if (nfields != VIR_NETWORK_DHCP_LEASE_FIELDS) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("Number of lease params aren't equal to: %d"),
+ VIR_NETWORK_DHCP_LEASE_FIELDS);
+ goto error;
+ }
+
+ if (mac && virMacAddrCompare(mac, lease_fields[1])) {
+ virStringFreeList(lease_fields);
+ continue;
+ }
+
+ if (need_results) {
+ if (VIR_ALLOC(lease) < 0)
+ goto error;
+
+ /* Convert expirytime here */
+ if (virStrToLong_ll(lease_fields[0], NULL, 10, &(lease->expirytime)) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("Unable to convert lease expiry time to integer: %s"),
+ lease_fields[0]);
+ goto error;
+ }
+
+ /* Unlike IPv4, IPv6 uses ':' instead of '.' as separator */
+ ipv6 = strchr(lease_fields[3], ':') ? true : false;
+
+ lease->type = ipv6 ? VIR_IP_ADDR_TYPE_IPV6 : VIR_IP_ADDR_TYPE_IPV4;
+ lease->prefix = virSocketAddrGetIpPrefix(&obj->def->ips->address,
+ &obj->def->ips->netmask,
+ obj->def->ips->prefix);
+
+ if ((VIR_STRDUP(lease->mac, lease_fields[1]) < 0) ||
+ (VIR_STRDUP(lease->ipaddr, lease_fields[3]) < 0) ||
+ (VIR_STRDUP(lease->interface, obj->def->bridge) < 0))
+ goto error;
+
+ /* IAID is NULL in case of ipv4 */
+ if (STREQ(lease_fields[2], "*"))
+ lease->iaid = NULL;
+ else if (VIR_STRDUP(lease->iaid, lease_fields[2]) < 0)
+ goto error;
+
+ /* Only two fields, hostname and clientid can be NULL
+ * Refer: http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2013q3/007544.html
+ */
+ if (STREQ(lease_fields[4], "*"))
+ lease->hostname = NULL;
+ else if (VIR_STRDUP(lease->hostname, lease_fields[4]) < 0)
+ goto error;
+
+ if (STREQ(lease_fields[5], "*"))
+ lease->clientid = NULL;
+ else if (VIR_STRDUP(lease->clientid, lease_fields[5]) < 0)
+ goto error;
+
+ if (VIR_INSERT_ELEMENT(leases_ret, nleases, nleases, lease) < 0)
+ goto error;
+ }
+ else
+ nleases++;
+
+ VIR_FREE(lease);
+ virStringFreeList(lease_fields);
+ }
+
+ lease_fields = NULL;
+
+ if (need_results && mac && !leases_ret) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("no lease with matching MAC address: %s"), mac);
+ goto error;
+ }
+
+ if (leases_ret) {
+ /* NULL terminated array */
+ ignore_value(VIR_REALLOC_N(leases_ret, nleases + 1));
+ *leases = leases_ret;
+ leases_ret = NULL;
+ }
+
+ rv = nleases;
+
+cleanup:
+ VIR_FREE(lease);
+ VIR_FREE(lease_file);
+ VIR_FREE(lease_entries);
+ if (lease_fields)
+ virStringFreeList(lease_fields);
+ return rv;
+
+error:
+ if (leases_ret) {
+ for (i = 0; i < nleases; i++)
+ virNetworkDHCPLeaseFree(leases_ret[i]);
+ VIR_FREE(leases_ret);
+ }
+ goto cleanup;
+}
+
+static int
+networkGetDHCPLeases(virNetworkPtr network,
+ virNetworkDHCPLeasesPtr **leases,
+ unsigned int flags)
+{
+ int rv = -1;
+ virNetworkObjPtr obj;
+
+ virCheckFlags(0, -1);
+
+ if (!(obj = networkObjFromNetwork(network)))
+ return rv;
+
+ if (virNetworkGetDHCPLeasesEnsureACL(network->conn, obj->def) < 0)
+ goto cleanup;
+
+ rv = networkGetDHCPLeasesHelper(obj, NULL, leases);
+
+cleanup:
+ if (obj)
+ virNetworkObjUnlock(obj);
+ return rv;
+}
+
+static int
+networkGetDHCPLeasesForMAC(virNetworkPtr network,
+ const char *mac,
+ virNetworkDHCPLeasesPtr **leases,
+ unsigned int flags)
+{
+ int rv = -1;
+ virNetworkObjPtr obj;
+
+ virCheckFlags(0, -1);
+
+ if (!(obj = networkObjFromNetwork(network)))
+ return rv;
+
+ if (virNetworkGetDHCPLeasesForMACEnsureACL(network->conn, obj->def) < 0)
+ goto cleanup;
+
+ rv = networkGetDHCPLeasesHelper(obj, mac, leases);
+
+cleanup:
+ if (obj)
+ virNetworkObjUnlock(obj);
+ return rv;
+}
static virNetworkDriver networkDriver = {
"Network",
@@ -3015,6 +3261,8 @@ static virNetworkDriver networkDriver = {
.networkSetAutostart = networkSetAutostart, /* 0.2.1 */
.networkIsActive = networkIsActive, /* 0.7.3 */
.networkIsPersistent = networkIsPersistent, /* 0.7.3 */
+ .networkGetDHCPLeases = networkGetDHCPLeases, /* 1.1.4 */
+ .networkGetDHCPLeasesForMAC = networkGetDHCPLeasesForMAC, /* 1.1.4 */
};
static virStateDriver networkStateDriver = {
--
1.8.1.4
More information about the libvir-list
mailing list