From 8a337b676f90040f96ef195a70262c26aec36019 Mon Sep 17 00:00:00 2001

Message-Id: <8a337b676f90040f96ef195a70262c26aec36019@dist-git>

From: Tony Krowiak <akrowiak@linux.vnet.ibm.com>

Date: Mon, 3 Nov 2014 10:00:22 -0500

Subject: [PATCH] util: Functions to update host network device's multicast

 filter

https://bugzilla.redhat.com/show_bug.cgi?id=848199

This patch provides the utility functions to needed to synchronize the

changes made to a guest domain network device's multicast filter

with the corresponding macvtap device's filter on the host:

* Get/add/remove multicast MAC addresses

* Get the macvtap device's RX filter list

Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com>

Signed-off-by: Laine Stump <laine@laine.org>

(cherry picked from commit cc0e8c244d080f56392278e836cc378ba848e7aa)

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

---

 src/libvirt_private.syms |   4 +

 src/util/virmacaddr.c    |  25 ++++

 src/util/virmacaddr.h    |   4 +

 src/util/virnetdev.c     | 329 +++++++++++++++++++++++++++++++++++++++++++++++

 src/util/virnetdev.h     |  10 ++

 5 files changed, 372 insertions(+)

diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms

index e2aae21..e7eba7e 100644

--- a/src/libvirt_private.syms

+++ b/src/libvirt_private.syms

@@ -1568,13 +1568,16 @@ virMacAddrIsBroadcastRaw;

 virMacAddrIsMulticast;

 virMacAddrIsUnicast;

 virMacAddrParse;

+virMacAddrParseHex;

 virMacAddrSet;

 virMacAddrSetRaw;

 # util/virnetdev.h

+virNetDevAddMulti;

 virNetDevAddRoute;

 virNetDevClearIPv4Address;

+virNetDevDelMulti;

 virNetDevExists;

 virNetDevGetIndex;

 virNetDevGetIPv4Address;

@@ -1582,6 +1585,7 @@ virNetDevGetLinkInfo;

 virNetDevGetMAC;

 virNetDevGetMTU;

 virNetDevGetPhysicalFunction;

+virNetDevGetRxFilter;

 virNetDevGetVirtualFunctionIndex;

 virNetDevGetVirtualFunctionInfo;

 virNetDevGetVirtualFunctions;

diff --git a/src/util/virmacaddr.c b/src/util/virmacaddr.c

index ebd1182..612a409 100644

--- a/src/util/virmacaddr.c

+++ b/src/util/virmacaddr.c

@@ -29,6 +29,7 @@

 #include "c-ctype.h"

 #include "virmacaddr.h"

 #include "virrandom.h"

+#include "virutil.h"

 static const unsigned char virMacAddrBroadcastAddrRaw[VIR_MAC_BUFLEN] =

     { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };

@@ -198,6 +199,30 @@ virMacAddrFormat(const virMacAddr *addr,

     return str;

 }

+/**

+ * virMacAddrParseHex:

+ * @str: string hexadecimal representation of MAC address, e.g., "F801EFCE3aCB"

+ * @addr: 6-byte MAC address

+ *

+ * Parse the hexadecimal representation of a MAC address

+ *

+ * Return 0 upon success, or -1 in case of error.

+ */

+int

+virMacAddrParseHex(const char *str, virMacAddrPtr addr)

+{

+    size_t i;

+

+    if (strspn(str, "0123456789abcdefABCDEF") != VIR_MAC_HEXLEN ||

+        str[VIR_MAC_HEXLEN])

+        return -1;

+

+    for (i = 0; i < VIR_MAC_BUFLEN; i++)

+        addr->addr[i] = (virHexToBin(str[2 * i]) << 4 |

+                         virHexToBin(str[2 * i + 1]));

+    return 0;

+}

+

 void virMacAddrGenerate(const unsigned char prefix[VIR_MAC_PREFIX_BUFLEN],

                         virMacAddrPtr addr)

 {

diff --git a/src/util/virmacaddr.h b/src/util/virmacaddr.h

index 49efc36..ae26867 100644

--- a/src/util/virmacaddr.h

+++ b/src/util/virmacaddr.h

@@ -27,6 +27,7 @@

 # include "internal.h"

 # define VIR_MAC_BUFLEN 6

+# define VIR_MAC_HEXLEN (VIR_MAC_BUFLEN * 2)

 # define VIR_MAC_PREFIX_BUFLEN 3

 # define VIR_MAC_STRING_BUFLEN (VIR_MAC_BUFLEN * 3)

@@ -50,6 +51,9 @@ void virMacAddrGenerate(const unsigned char prefix[VIR_MAC_PREFIX_BUFLEN],

                         virMacAddrPtr addr);

 int virMacAddrParse(const char* str,

                     virMacAddrPtr addr) ATTRIBUTE_RETURN_CHECK;

+int virMacAddrParseHex(const char* str,

+                       virMacAddrPtr addr)

+    ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK;

 bool virMacAddrIsUnicast(const virMacAddr *addr);

 bool virMacAddrIsMulticast(const virMacAddr *addr);

 bool virMacAddrIsBroadcastRaw(const unsigned char s[VIR_MAC_BUFLEN]);

diff --git a/src/util/virnetdev.c b/src/util/virnetdev.c

index 36b5a49..381031a 100644

--- a/src/util/virnetdev.c

+++ b/src/util/virnetdev.c

@@ -56,6 +56,35 @@

 VIR_LOG_INIT("util.netdev");

+#define PROC_NET_DEV_MCAST "/proc/net/dev_mcast"

+#define MAX_MCAST_SIZE 50*14336

+#define VIR_MCAST_NAME_LEN (IFNAMSIZ + 1)

+#define VIR_MCAST_INDEX_TOKEN_IDX 0

+#define VIR_MCAST_NAME_TOKEN_IDX 1

+#define VIR_MCAST_USERS_TOKEN_IDX 2

+#define VIR_MCAST_GLOBAL_TOKEN_IDX 3

+#define VIR_MCAST_ADDR_TOKEN_IDX 4

+#define VIR_MCAST_NUM_TOKENS 5

+#define VIR_MCAST_TOKEN_DELIMS " \n"

+#define VIR_MCAST_ADDR_LEN (VIR_MAC_HEXLEN + 1)

+

+typedef struct _virNetDevMcastEntry virNetDevMcastEntry;

+typedef virNetDevMcastEntry *virNetDevMcastEntryPtr;

+struct _virNetDevMcastEntry  {

+        int index;

+        char name[VIR_MCAST_NAME_LEN];

+        int users;

+        bool global;

+        virMacAddr macaddr;

+};

+

+typedef struct _virNetDevMcastList virNetDevMcastList;

+typedef virNetDevMcastList *virNetDevMcastListPtr;

+struct _virNetDevMcastList {

+    size_t nentries;

+    virNetDevMcastEntryPtr *entries;

+};

+

 #if defined(HAVE_STRUCT_IFREQ)

 static int virNetDevSetupControlFull(const char *ifname,

                                      struct ifreq *ifr,

@@ -1935,6 +1964,238 @@ virNetDevGetLinkInfo(const char *ifname,

 #endif /* defined(__linux__) */

+#if defined(SIOCADDMULTI) && defined(HAVE_STRUCT_IFREQ)

+/**

+ * virNetDevAddMulti:

+ * @ifname: interface name to which to add multicast MAC address

+ * @macaddr: MAC address

+ *

+ * This function adds the @macaddr to the multicast list for a given interface

+ * @ifname.

+ *

+ * Returns 0 in case of success or -1 on failure

+ */

+int virNetDevAddMulti(const char *ifname,

+                      virMacAddrPtr macaddr)

+{

+    int fd = -1;

+    int ret = -1;

+    struct ifreq ifr;

+

+    if ((fd = virNetDevSetupControl(ifname, &ifr)) < 0)

+        return -1;

+

+    ifr.ifr_hwaddr.sa_family = AF_UNSPEC;

+    virMacAddrGetRaw(macaddr, (unsigned char *)ifr.ifr_hwaddr.sa_data);

+

+    if (ioctl(fd, SIOCADDMULTI, &ifr) < 0) {

+        char macstr[VIR_MAC_STRING_BUFLEN];

+        virReportSystemError(errno,

+                             _("Cannot add multicast MAC %s on '%s' interface"),

+                             virMacAddrFormat(macaddr, macstr), ifname);

+        goto cleanup;

+    }

+

+    ret = 0;

+ cleanup:

+    VIR_FORCE_CLOSE(fd);

+    return ret;

+}

+#else

+int virNetDevAddMulti(const char *ifname ATTRIBUTE_UNUSED,

+                      virMacAddrPtr macaddr ATTRIBUTE_UNUSED)

+{

+    virReportSystemError(ENOSYS, "%s",

+                         _("Unable to add address to interface "

+                           "multicast list on this platform"));

+    return -1;

+}

+#endif

+

+#if defined(SIOCDELMULTI) && defined(HAVE_STRUCT_IFREQ)

+/**

+ * virNetDevDelMulti:

+ * @ifname: interface name from which to delete the multicast MAC address

+ * @macaddr: MAC address

+ *

+ * This function deletes the @macaddr from the multicast list for a given

+ * interface @ifname.

+ *

+ * Returns 0 in case of success or -1 on failure

+ */

+int virNetDevDelMulti(const char *ifname,

+                      virMacAddrPtr macaddr)

+{

+    int fd = -1;

+    int ret = -1;

+    struct ifreq ifr;

+

+    if ((fd = virNetDevSetupControl(ifname, &ifr)) < 0)

+        return -1;

+

+    ifr.ifr_hwaddr.sa_family = AF_UNSPEC;

+    virMacAddrGetRaw(macaddr, (unsigned char *)ifr.ifr_hwaddr.sa_data);

+

+    if (ioctl(fd, SIOCDELMULTI, &ifr) < 0) {

+        char macstr[VIR_MAC_STRING_BUFLEN];

+        virReportSystemError(errno,

+                             _("Cannot add multicast MAC %s on '%s' interface"),

+                             virMacAddrFormat(macaddr, macstr), ifname);

+        goto cleanup;

+    }

+

+    ret = 0;

+ cleanup:

+    VIR_FORCE_CLOSE(fd);

+    return ret;

+}

+#else

+int virNetDevDelMulti(const char *ifname ATTRIBUTE_UNUSED,

+                      virMacAddrPtr macaddr ATTRIBUTE_UNUSED)

+{

+    virReportSystemError(ENOSYS, "%s",

+                         _("Unable to delete address from interface "

+                           "multicast list on this platform"));

+    return -1;

+}

+#endif

+

+static int virNetDevParseMcast(char *buf, virNetDevMcastEntryPtr mcast)

+{

+    int ifindex;

+    int num;

+    char *next;

+    char *token;

+    char *saveptr;

+    char *endptr;

+

+    for (ifindex = 0, next = buf; ifindex < VIR_MCAST_NUM_TOKENS; ifindex++,

+         next = NULL) {

+        token = strtok_r(next, VIR_MCAST_TOKEN_DELIMS, &saveptr);

+

+        if (token == NULL) {

+            virReportSystemError(EINVAL,

+                                 _("failed to parse multicast address from '%s'"),

+                                 buf);

+            return -1;

+        }

+

+        switch (ifindex) {

+            case VIR_MCAST_INDEX_TOKEN_IDX:

+                if (virStrToLong_i(token, &endptr, 10, &num) < 0) {

+                    virReportSystemError(EINVAL,

+                                         _("Failed to parse interface index from '%s'"),

+                                         buf);

+                    return -1;

+

+                }

+                mcast->index = num;

+                break;

+            case VIR_MCAST_NAME_TOKEN_IDX:

+                if (virStrncpy(mcast->name, token, strlen(token),

+                    VIR_MCAST_NAME_LEN) == NULL) {

+                    virReportSystemError(EINVAL,

+                                         _("Failed to parse network device name from '%s'"),

+                                         buf);

+                    return -1;

+                }

+                break;

+            case VIR_MCAST_USERS_TOKEN_IDX:

+                if (virStrToLong_i(token, &endptr, 10, &num) < 0) {

+                    virReportSystemError(EINVAL,

+                                         _("Failed to parse users from '%s'"),

+                                         buf);

+                    return -1;

+

+                }

+                mcast->users = num;

+                break;

+            case VIR_MCAST_GLOBAL_TOKEN_IDX:

+                if (virStrToLong_i(token, &endptr, 10, &num) < 0) {

+                    virReportSystemError(EINVAL,

+                                         _("Failed to parse users from '%s'"),

+                                         buf);

+                    return -1;

+

+                }

+                mcast->global = num;

+                break;

+            case VIR_MCAST_ADDR_TOKEN_IDX:

+                if (virMacAddrParseHex((const char*)token,

+                    &mcast->macaddr) < 0) {

+                    virReportSystemError(EINVAL,

+                                         _("Failed to parse MAC address from '%s'"),

+                                         buf);

+                }

+                break;

+            default:

+                break;

+        }

+    }

+    return 0;

+}

+

+

+static void virNetDevMcastListClear(virNetDevMcastListPtr mcast)

+{

+    size_t i;

+

+    for (i = 0; i < mcast->nentries; i++)

+       VIR_FREE(mcast->entries[i]);

+    VIR_FREE(mcast->entries);

+    mcast->nentries = 0;

+}

+

+

+static int virNetDevGetMcastList(const char *ifname,

+                                 virNetDevMcastListPtr mcast)

+{

+    char *cur = NULL;

+    char *buf = NULL;

+    char *next = NULL;

+    int ret = -1, len;

+    virNetDevMcastEntryPtr entry = NULL;

+

+    mcast->entries = NULL;

+    mcast->nentries = 0;

+

+    /* Read entire multicast table into memory */

+    if ((len = virFileReadAll(PROC_NET_DEV_MCAST, MAX_MCAST_SIZE, &buf)) <= 0)

+        goto cleanup;

+

+    cur = buf;

+    while (cur) {

+        if (!entry && VIR_ALLOC(entry) < 0)

+                goto cleanup;

+

+        next = strchr(cur, '\n');

+        if (next)

+            next++;

+        if (virNetDevParseMcast(cur, entry))

+            goto cleanup;

+

+        /* Only return global multicast MAC addresses for

+         * specified interface */

+        if (entry->global && STREQ(ifname, entry->name)) {

+            if (VIR_APPEND_ELEMENT(mcast->entries, mcast->nentries, entry))

+                 goto cleanup;

+        } else {

+            memset(entry, 0, sizeof(virNetDevMcastEntry));

+        }

+        cur = next && ((next - buf) < len) ? next : NULL;

+    }

+

+    ret = 0;

+ cleanup:

+    if (ret < 0)

+        virNetDevMcastListClear(mcast);

+

+    VIR_FREE(entry);

+

+    return ret;

+}

+

+

 VIR_ENUM_IMPL(virNetDevRxFilterMode,

               VIR_NETDEV_RX_FILTER_MODE_LAST,

               "none",

@@ -1942,6 +2203,38 @@ VIR_ENUM_IMPL(virNetDevRxFilterMode,

               "all");

+static int virNetDevGetMulticastTable(const char *ifname,

+                                      virNetDevRxFilterPtr filter)

+{

+    size_t i;

+    int ret = -1;

+    virNetDevMcastList mcast;

+    filter->multicast.nTable = 0;

+    filter->multicast.table = NULL;

+

+    if (virNetDevGetMcastList(ifname, &mcast) < 0)

+        goto cleanup;

+

+    if (mcast.nentries > 0) {

+        if (VIR_ALLOC_N(filter->multicast.table, mcast.nentries) < 0)

+            goto cleanup;

+

+        for (i = 0; i < mcast.nentries; i++) {

+            virMacAddrSet(&filter->multicast.table[i],

+                          &mcast.entries[i]->macaddr);

+        }

+

+        filter->multicast.nTable = mcast.nentries;

+    }

+

+    ret = 0;

+ cleanup:

+    virNetDevMcastListClear(&mcast);

+

+    return ret;

+}

+

+

 virNetDevRxFilterPtr

 virNetDevRxFilterNew(void)

 {

@@ -1964,3 +2257,39 @@ virNetDevRxFilterFree(virNetDevRxFilterPtr filter)

         VIR_FREE(filter);

     }

 }

+

+

+/**

+ * virNetDevGetRxFilter:

+ * This function supplies the RX filter list for a given device interface

+ *

+ * @ifname: Name of the interface

+ * @filter: The RX filter list

+ *

+ * Returns 0 or -1 on failure.

+ */

+int virNetDevGetRxFilter(const char *ifname,

+                         virNetDevRxFilterPtr *filter)

+{

+    int ret = -1;

+    virNetDevRxFilterPtr fil = virNetDevRxFilterNew();

+

+    if (!fil)

+        goto cleanup;

+

+    if (virNetDevGetMAC(ifname, &fil->mac))

+        goto cleanup;

+

+    if (virNetDevGetMulticastTable(ifname, fil))

+        goto cleanup;

+

+    ret = 0;

+ cleanup:

+    if (ret < 0) {

+        virNetDevRxFilterFree(fil);

+        fil = NULL;

+    }

+

+    *filter = fil;

+    return ret;

+}

diff --git a/src/util/virnetdev.h b/src/util/virnetdev.h

index 2a6e67d..ac4beff 100644

--- a/src/util/virnetdev.h

+++ b/src/util/virnetdev.h

@@ -189,5 +189,15 @@ int virNetDevGetLinkInfo(const char *ifname,

 virNetDevRxFilterPtr virNetDevRxFilterNew(void)

    ATTRIBUTE_RETURN_CHECK;

 void virNetDevRxFilterFree(virNetDevRxFilterPtr filter);

+int virNetDevGetRxFilter(const char *ifname,

+                         virNetDevRxFilterPtr *filter)

+    ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK;

+

+int virNetDevAddMulti(const char *ifname,

+                      virMacAddrPtr macaddr)

+    ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK;

+int virNetDevDelMulti(const char *ifname,

+                      virMacAddrPtr macaddr)

+    ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK;

 #endif /* __VIR_NETDEV_H__ */

-- 

2.1.3