[libvirt] [PATCH 06/33] Add an API for retrieving the MAC address of an interface

From: "Daniel P. Berrange" <berrange(a)redhat.com&gt; * src/util/bridge.c, src/util/bridge.h: Add virNetDevGetMAC --- src/util/bridge.c | 35 +++++++++++++++++++++++++++++++++++ src/util/bridge.h | 3 +++ 2 files changed, 38 insertions(+), 0 deletions(-) diff --git a/src/util/bridge.c b/src/util/bridge.c index 247ce93..3a7012c 100644 --- a/src/util/bridge.c +++ b/src/util/bridge.c @@ -358,6 +358,41 @@ cleanup: } /** + * virNetDevGetMAC: + * @ifname: interface name to set MTU for + * @macaddr: MAC address (VIR_MAC_BUFLEN in size) + * + * This function gets the @macaddr for a given interface @ifname. + * + * Returns 0 in case of success or -1 on failure + */ +int virNetDevGetMAC(const char *ifname, + unsigned char *macaddr) +{ + int fd = -1; + int ret = -1; + struct ifreq ifr; + + if ((fd = virNetDevSetupControl(ifname, &ifr)) < 0) + return -1; + + if (ioctl(fd, SIOCGIFHWADDR, &ifr) < 0) { + virReportSystemError(errno, + _("Cannot get interface MAC on '%s'"), + ifname); + goto cleanup; + } + + memcpy(macaddr, ifr.ifr_hwaddr.sa_data, VIR_MAC_BUFLEN); + + ret = 0; + +cleanup: + VIR_FORCE_CLOSE(fd); + return ret; +} + +/** * virNetDevGetMTU: * @ifname: interface name get MTU for * diff --git a/src/util/bridge.h b/src/util/bridge.h index 0cc89c0..7504925 100644 --- a/src/util/bridge.h +++ b/src/util/bridge.h @@ -112,6 +112,9 @@ int virNetDevTapCreate(char **ifname, int virNetDevSetMAC(const char *ifname, const unsigned char *macaddr) ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK; +int virNetDevGetMAC(const char *ifname, + unsigned char *macaddr) + ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK; int virNetDevSetMTU(const char *ifname, int mtu) ATTRIBUTE_NONNULL(1) ATTRIBUTE_RETURN_CHECK; -- 1.7.6.4