[libvirt] [PATCHv5 1/4] net-dhcp-leases: Implement the public APIs
Nehal J Wani
nehaljw.kkd1 at gmail.com
Mon Nov 25 21:05:58 UTC 2013
Introduce 3 new APIs, virNetworkGetDHCPLeases, virNetworkGetDHCPLeasesForMAC
and virNetworkDHCPLeaseFree.
* virNetworkGetDHCPLeases: returns the dhcp leases information for a given
virtual network.
For DHCPv4, the information returned:
- Network Interface Name
- Expiry Time
- MAC address (can be NULL, only in rare cases)
- IAID (NULL)
- IPv4 address (with type and prefix)
- Hostname (can be NULL)
- Client ID (can be NULL)
For DHCPv6, the information returned:
- Network Interface Name
- Expiry Time
- MAC address (can be NULL, only in rare cases)
- IAID (can be NULL, only in rare cases)
- IPv6 address (with type and prefix)
- Hostname (can be NULL)
- Client DUID
Note: @mac, @iaid, @ipaddr, @clientid are in ASCII form, not raw bytes.
Note: @expirytime can 0, in case the lease is for infinite time.
* virNetworkGetDHCPLeasesForMAC: returns the dhcp leases information for a
given virtual network and specified MAC Address.
* virNetworkDHCPLeaseFree: allows the upper layer application to free the
network interface object conveniently.
There is no support for flags, so user is expected to pass 0 for
both the APIs.
include/libvirt/libvirt.h.in:
* Define virNetworkGetDHCPLeases
* Define virNetworkGetDHCPLeasesForMAC
* Define virNetworkDHCPLeaseFree
src/driver.h:
* Define networkGetDHCPLeases
* Define networkGetDHCPLeasesForMAC
src/libvirt.c:
* Implement virNetworkGetDHCPLeases
* Implement virNetworkGetDHCPLeasesForMAC
* Implement virNetworkDHCPLeaseFree
src/libvirt_public.syms:
* Export the new symbols
src/util/leaseshelper.c:
* Helper program to create custom leases file
src/Makefile.am:
* Add compiler flags for the helper file leaseshelper.c
* Add virmacaddr.c to libvirt_setuid_rpc_client_la_SOURCES
---
include/libvirt/libvirt.h.in | 35 ++++++++
src/Makefile.am | 21 +++++
src/driver.h | 13 +++
src/libvirt.c | 197 +++++++++++++++++++++++++++++++++++++++++++
src/libvirt_public.syms | 7 ++
src/util/leaseshelper.c | 185 ++++++++++++++++++++++++++++++++++++++++
6 files changed, 458 insertions(+)
create mode 100644 src/util/leaseshelper.c
diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in
index 5aad75c..20ea40a 100644
--- a/include/libvirt/libvirt.h.in
+++ b/include/libvirt/libvirt.h.in
@@ -2826,6 +2826,41 @@ int virConnectNumOfDefinedInterfaces (virConnectPtr conn);
int virConnectListDefinedInterfaces (virConnectPtr conn,
char **const names,
int maxnames);
+
+typedef enum {
+ VIR_IP_ADDR_TYPE_IPV4,
+ VIR_IP_ADDR_TYPE_IPV6,
+
+#ifdef VIR_ENUM_SENTINELS
+ VIR_IP_ADDR_TYPE_LAST
+#endif
+} virIPAddrType;
+
+typedef struct _virNetworkDHCPLeases virNetworkDHCPLeases;
+typedef virNetworkDHCPLeases *virNetworkDHCPLeasesPtr;
+struct _virNetworkDHCPLeases {
+ char *interface; /* Network interface name */
+ long long expirytime; /* Seconds since epoch */
+ int type; /* virIPAddrType */
+ char *mac; /* MAC address */
+ char *iaid; /* IAID */
+ char *ipaddr; /* IP address */
+ unsigned int prefix; /* IP address prefix */
+ char *hostname; /* Hostname */
+ char *clientid; /* Client ID or DUID */
+};
+
+void virNetworkDHCPLeaseFree(virNetworkDHCPLeasesPtr lease);
+
+int virNetworkGetDHCPLeases(virNetworkPtr network,
+ virNetworkDHCPLeasesPtr **leases,
+ unsigned int flags);
+
+int virNetworkGetDHCPLeasesForMAC(virNetworkPtr network,
+ const char *mac,
+ virNetworkDHCPLeasesPtr **leases,
+ unsigned int flags);
+
/*
* virConnectListAllInterfaces:
*
diff --git a/src/Makefile.am b/src/Makefile.am
index 87f5101..772171c 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -829,6 +829,9 @@ STORAGE_HELPER_DISK_SOURCES = \
UTIL_IO_HELPER_SOURCES = \
util/iohelper.c
+UTIL_IO_LEASES_SOURCES = \
+ util/leaseshelper.c
+
# Network filters
NWFILTER_DRIVER_SOURCES = \
nwfilter/nwfilter_driver.h nwfilter/nwfilter_driver.c \
@@ -2019,6 +2022,7 @@ libvirt_setuid_rpc_client_la_SOURCES = \
util/virtypedparam.c \
util/viruri.c \
util/virutil.c \
+ util/virmacaddr.c \
util/viruuid.c \
conf/domain_event.c \
rpc/virnetsocket.c \
@@ -2397,6 +2401,23 @@ libvirt_iohelper_CFLAGS = \
$(NULL)
endif WITH_LIBVIRTD
+if WITH_LIBVIRTD
+libexec_PROGRAMS += libvirt_leaseshelper
+libvirt_leaseshelper_SOURCES = $(UTIL_IO_LEASES_SOURCES)
+libvirt_leaseshelper_LDFLAGS = \
+ $(NULL)
+libvirt_leaseshelper_LDADD = \
+ libvirt_util.la \
+ ../gnulib/lib/libgnu.la
+if WITH_DTRACE_PROBES
+libvirt_leaseshelper_LDADD += libvirt_probes.lo
+endif WITH_DTRACE_PROBES
+
+libvirt_leaseshelper_CFLAGS = \
+ $(PIE_CFLAGS) \
+ $(NULL)
+endif WITH_LIBVIRTD
+
if WITH_STORAGE_DISK
if WITH_LIBVIRTD
libexec_PROGRAMS += libvirt_parthelper
diff --git a/src/driver.h b/src/driver.h
index 8cd164a..e000b17 100644
--- a/src/driver.h
+++ b/src/driver.h
@@ -1127,6 +1127,17 @@ typedef int
int cookieinlen,
unsigned int flags,
int cancelled);
+typedef int
+(*virDrvNetworkGetDHCPLeases)(virNetworkPtr network,
+ virNetworkDHCPLeasesPtr **leases,
+ unsigned int flags);
+
+typedef int
+(*virDrvNetworkGetDHCPLeasesForMAC)(virNetworkPtr network,
+ const char *mac,
+ virNetworkDHCPLeasesPtr **leases,
+ unsigned int flags);
+
typedef struct _virDriver virDriver;
typedef virDriver *virDriverPtr;
@@ -1458,6 +1469,8 @@ struct _virNetworkDriver {
virDrvNetworkSetAutostart networkSetAutostart;
virDrvNetworkIsActive networkIsActive;
virDrvNetworkIsPersistent networkIsPersistent;
+ virDrvNetworkGetDHCPLeases networkGetDHCPLeases;
+ virDrvNetworkGetDHCPLeasesForMAC networkGetDHCPLeasesForMAC;
};
diff --git a/src/libvirt.c b/src/libvirt.c
index eff44eb..9a0b872 100644
--- a/src/libvirt.c
+++ b/src/libvirt.c
@@ -68,6 +68,7 @@
#include "virstring.h"
#include "virutil.h"
#include "virtypedparam.h"
+#include "virmacaddr.h"
#ifdef WITH_TEST
# include "test/test_driver.h"
@@ -22051,3 +22052,199 @@ error:
virDispatchError(dom->conn);
return -1;
}
+
+/**
+ * virNetworkGetDHCPLeases:
+ * @network: Pointer to network object
+ * @leases: Pointer to a variable to store the array containing details on
+ * obtained leases, or NULL if the list is not required (just returns
+ * number of leases).
+ * @flags: Extra flags, not used yet, so callers should always pass 0
+ *
+ * For DHCPv4, the information returned:
+ * - Network Interface Name
+ * - Expiry Time
+ * - MAC address (can be NULL, only in rare cases)
+ * - IAID (NULL)
+ * - IPv4 address (with type and prefix)
+ * - Hostname (can be NULL)
+ * - Client ID (can be NULL)
+ *
+ * For DHCPv6, the information returned:
+ * - Network Interface Name
+ * - Expiry Time
+ * - MAC address (can be NULL, only in rare cases)
+ * - IAID (can be NULL, only in rare cases)
+ * - IPv6 address (with type and prefix)
+ * - Hostname (can be NULL)
+ * - Client DUID
+ *
+ * Note: @mac, @iaid, @ipaddr, @clientid are in ASCII form, not raw bytes.
+ * Note: @expirytime can 0, in case the lease is for infinite time.
+ *
+ * Returns the number of leases found or -1 and sets @leases to NULL in
+ * case of error. On success, the array stored into @leases is guaranteed to
+ * have an extra allocated element set to NULL but not included in the return
+ * count, to make iteration easier. The caller is responsible for calling
+ * virNetworkDHCPLeaseFree() on each array element, then calling free() on @leases.
+ *
+ * See also virNetworkGetDHCPLeasesForMAC() as a convenience for filtering
+ * the list to a single MAC address.
+ *
+ * Example of usage:
+ *
+ * virNetworkDHCPLeasesPtr *leases = NULL;
+ * virNetworkPtr network = ... obtain a network pointer here ...;
+ * size_t i;
+ * int nleases;
+ * unsigned int flags = 0;
+ *
+ * nleases = virNetworkGetDHCPLeases(network, &leases, flags);
+ * if (nleases < 0)
+ * error();
+ *
+ * ... do something with returned values, for example:
+ *
+ * for (i = 0; i < nleases; i++) {
+ * virNetworkDHCPLeasesPtr lease = leases[i];
+ *
+ * printf("Time(epoch): %lu, MAC address: %s, "
+ * "IP address: %s, Hostname: %s, ClientID: %s\n",
+ * leas->expirytime, lease->mac, lease->ipaddr,
+ * lease->hostname, lease->clientid);
+ *
+ * virNetworkDHCPLeaseFree(leases[i]);
+ * }
+ *
+ * free(leases);
+ *
+ */
+int
+virNetworkGetDHCPLeases(virNetworkPtr network,
+ virNetworkDHCPLeasesPtr **leases,
+ unsigned int flags)
+{
+ virConnectPtr conn;
+ VIR_DEBUG("network=%p, leases=%p, flags=%x",
+ network, leases, flags);
+
+ virResetLastError();
+
+ if (leases)
+ *leases = NULL;
+
+ if (!VIR_IS_CONNECTED_NETWORK(network)) {
+ virLibNetworkError(VIR_ERR_INVALID_NETWORK, __FUNCTION__);
+ virDispatchError(NULL);
+ return -1;
+ }
+
+ conn = network->conn;
+
+ if (conn->networkDriver && conn->networkDriver->networkGetDHCPLeases) {
+ int ret;
+ ret = conn->networkDriver->networkGetDHCPLeases(network, leases, flags);
+ if (ret < 0)
+ goto error;
+ return ret;
+ }
+
+ virLibConnError(VIR_ERR_NO_SUPPORT, __FUNCTION__);
+
+error:
+ virDispatchError(network->conn);
+ return -1;
+}
+
+/**
+ * virNetworkGetDHCPLeasesForMAC:
+ * @network: Pointer to network object
+ * @mac: ASCII formatted MAC address of an interface
+ * @leases: Pointer to a variable to store the array containing details on
+ * obtained leases, or NULL if the list is not required (just returns
+ * number of leases).
+ * @flags: extra flags, not used yet, so callers should always pass 0
+ *
+ * The API fetches leases info of the interface which matches with the
+ * given @mac. There can be multiple leases for a single @mac because this
+ * API supports DHCPv6 too.
+ *
+ * Returns the number of leases found or -1 and sets @leases to NULL in case of
+ * error. On success, the array stored into @leases is guaranteed to have an
+ * extra allocated element set to NULL but not included in the return count,
+ * to make iteration easier. The caller is responsible for calling
+ * virNetworkDHCPLeaseFree() on each array element, then calling free() on @leases.
+ *
+ * See virNetworkGetDHCPLeases() for more details on list contents.
+ */
+int
+virNetworkGetDHCPLeasesForMAC(virNetworkPtr network,
+ const char *mac,
+ virNetworkDHCPLeasesPtr **leases,
+ unsigned int flags)
+{
+ virConnectPtr conn;
+ virMacAddr addr;
+
+ VIR_DEBUG("network=%p, mac=%s, leases=%p, flags=%x",
+ network, mac, leases, flags);
+
+ virResetLastError();
+
+ if (leases)
+ *leases = NULL;
+
+ virCheckNonNullArgGoto(mac, error);
+
+ if (!VIR_IS_CONNECTED_NETWORK(network)) {
+ virLibNetworkError(VIR_ERR_INVALID_NETWORK, __FUNCTION__);
+ virDispatchError(NULL);
+ return -1;
+ }
+
+ /* Validate the MAC address */
+ if (virMacAddrParse(mac, &addr) < 0) {
+ virReportInvalidArg(mac, "%s",
+ _("Given MAC Address doesn't comply "
+ "with the standard (IEEE 802) format"));
+ goto error;
+ }
+
+ conn = network->conn;
+
+ if (conn->networkDriver &&
+ conn->networkDriver->networkGetDHCPLeasesForMAC) {
+ int ret;
+ ret = conn->networkDriver->networkGetDHCPLeasesForMAC(network, mac,
+ leases, flags);
+ if (ret < 0)
+ goto error;
+ return ret;
+ }
+
+ virLibConnError(VIR_ERR_NO_SUPPORT, __FUNCTION__);
+
+error:
+ virDispatchError(network->conn);
+ return -1;
+}
+
+/**
+ * virNetworkDHCPLeaseFree:
+ * @lease: pointer to a leases object
+ *
+ * Frees all the memory occupied by @lease.
+ */
+void
+virNetworkDHCPLeaseFree(virNetworkDHCPLeasesPtr lease)
+{
+ if (!lease)
+ return;
+ VIR_FREE(lease->interface);
+ VIR_FREE(lease->mac);
+ VIR_FREE(lease->iaid);
+ VIR_FREE(lease->ipaddr);
+ VIR_FREE(lease->hostname);
+ VIR_FREE(lease->clientid);
+ VIR_FREE(lease);
+}
diff --git a/src/libvirt_public.syms b/src/libvirt_public.syms
index fe9b497..f1a9707 100644
--- a/src/libvirt_public.syms
+++ b/src/libvirt_public.syms
@@ -639,4 +639,11 @@ LIBVIRT_1.1.3 {
virConnectGetCPUModelNames;
} LIBVIRT_1.1.1;
+LIBVIRT_1.1.4 {
+ global:
+ virNetworkDHCPLeaseFree;
+ virNetworkGetDHCPLeases;
+ virNetworkGetDHCPLeasesForMAC;
+} LIBVIRT_1.1.3;
+
# .... define new API here using predicted next version number ....
diff --git a/src/util/leaseshelper.c b/src/util/leaseshelper.c
new file mode 100644
index 0000000..53d7d22
--- /dev/null
+++ b/src/util/leaseshelper.c
@@ -0,0 +1,185 @@
+/*
+ * leasehelper.c: Helper program to create custom leases file
+ *
+ * Copyright (C) 2013 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Author: Nehal J Wani <nehaljw.kkd1 at gmail.com>
+ *
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "virutil.h"
+#include "virfile.h"
+#include "virbuffer.h"
+#include "virstring.h"
+#include "virerror.h"
+#include "viralloc.h"
+#include "configmake.h"
+
+#define VIR_FROM_THIS VIR_FROM_NETWORK
+
+/**
+ * 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
+/**
+ * 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
+
+/*
+ * Use this when passing possibly-NULL strings to printf-a-likes.
+ */
+# define NULL_STR(s) ((s) ? (s) : "*")
+
+int
+main(int argc, char **argv) {
+
+ /* Doesn't hurt to check */
+ if (argc < 4)
+ return -1;
+
+ const char *action = argv[1];
+ const char *interface = NULL_STR(getenv("DNSMASQ_INTERFACE"));
+ const char *expirytime = NULL_STR(getenv("DNSMASQ_LEASE_EXPIRES"));
+ const char *mac = argv[2];
+ const char *ip = argv[3];
+ const char *iaid = NULL_STR(getenv("DNSMASQ_IAID"));
+ const char *hostname = NULL_STR(getenv("DNSMASQ_SUPPLIED_HOSTNAME"));
+ const char *clientid = NULL_STR(getenv("DNSMASQ_CLIENT_ID"));
+ const char *leases_str = NULL;
+ char *lease_file = NULL;
+ char *lease_entries = NULL;
+ char *lease_entry = NULL;
+ char **lease_fields = NULL;
+ bool delete = false;
+ bool add = false;
+ int rv = -1;
+ int lease_file_len = 0;
+ FILE *fp = NULL;
+ virBuffer buf_new_lease = VIR_BUFFER_INITIALIZER;
+ virBuffer buf_all_leases = VIR_BUFFER_INITIALIZER;
+
+ if (virAsprintf(&lease_file, "%s/%s.status", LOCALSTATEDIR
+ "/lib/libvirt/dnsmasq/", interface) < 0)
+ goto cleanup;
+
+ if (getenv("DNSMASQ_IAID")) {
+ mac = NULL_STR(getenv("DNSMASQ_MAC"));
+ clientid = argv[2];
+ }
+
+ /* Make sure the file exists. If not, 'touch' it */
+ fp = fopen(lease_file, "a+");
+ fclose(fp);
+
+ /* Read entire contents */
+ if ((lease_file_len = virFileReadAll(lease_file,
+ VIR_NETWORK_DHCP_LEASE_FILE_SIZE_MAX,
+ &lease_entries)) < 0) {
+ goto cleanup;
+ }
+
+
+ if (STREQ(action, "add") || STREQ(action, "old") || STREQ(action, "del")) {
+ if (mac || STREQ(action, "del")) {
+ /* Delete the corresponding lease */
+ delete = true;
+ if (STREQ(action, "add") || STREQ(action, "old")) {
+ add = true;
+ /* Enter new lease */
+ virBufferAsprintf(&buf_new_lease, "%s %s %s %s %s %s\n",
+ expirytime, mac, iaid, ip, hostname, clientid);
+
+ if (virBufferError(&buf_new_lease)) {
+ virBufferFreeAndReset(&buf_new_lease);
+ virReportOOMError();
+ goto cleanup;
+ }
+ }
+ }
+ }
+
+ lease_entry = lease_entries[0] == '\0' ? NULL : lease_entries;
+
+ while (lease_entry) {
+ int nfields = 0;
+
+ char *eol = strchr(lease_entry, '\n');
+ *eol = '\0';
+
+ /* Split the lease line */
+ if (!(lease_fields = virStringSplit(lease_entry, " ",
+ VIR_NETWORK_DHCP_LEASE_FIELDS)))
+ goto cleanup;
+
+ 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)
+ goto cleanup;
+
+ if (delete && STREQ(lease_fields[3], ip))
+ continue;
+ else {
+ virBufferAsprintf(&buf_all_leases, "%s %s %s %s %s %s\n",
+ lease_fields[0], lease_fields[1], lease_fields[2],
+ lease_fields[3], lease_fields[4], lease_fields[5]);
+
+ if (virBufferError(&buf_all_leases)) {
+ virBufferFreeAndReset(&buf_all_leases);
+ virReportOOMError();
+ goto cleanup;
+ }
+ }
+ }
+
+ if (add)
+ virBufferAsprintf(&buf_all_leases, "%s", virBufferContentAndReset(&buf_new_lease));
+
+ rv = 0;
+
+ /* Write to file */
+ leases_str = virBufferContentAndReset(&buf_all_leases);
+ if (!leases_str)
+ leases_str = "";
+
+ if (virFileWriteStr(lease_file, leases_str, 0) < 0)
+ rv = -1;
+
+cleanup:
+ VIR_FREE(lease_file);
+ VIR_FREE(lease_entries);
+ if (lease_fields)
+ virStringFreeList(lease_fields);
+ return rv;
+}
--
1.8.1.4
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