[libvirt] [PATCH 2/3] Set broadcast address for IPv4 addresses on virtual network bridges

[Stefan Berger]

On 12/31/2010 06:33 AM, Laine Stump wrote:
> Previously we used ioctl() to set the IP address and netmask of the
> bridges used for virtual networks, and apparently the SIOCSIFNETMASK
> ioctl implicitly set the broadcast address for the interface. The new
> method of using the "ip" command requires broadcast address to be
> explicitly specified though.
> ---
>   src/util/bridge.c |   12 +++++++++++-
>   1 files changed, 11 insertions(+), 1 deletions(-)
>
> diff --git a/src/util/bridge.c b/src/util/bridge.c
> index 81a043c..e53fce5 100644
> --- a/src/util/bridge.c
> +++ b/src/util/bridge.c
> @@ -677,14 +677,23 @@ brAddInetAddress(brControl *ctl ATTRIBUTE_UNUSED,
>                    unsigned int prefix)
>   {
>       virCommandPtr cmd = NULL;
> -    char *addrstr;
> +    char *addrstr = NULL, *bcaststr = NULL;
> +    virSocketAddr broadcast;
>       int ret = -1;
>
>       if (!(addrstr = virSocketFormatAddr(addr)))
>           goto cleanup;
> +    /* format up a broadcast address if this is IPv4 */
> +    if ((VIR_SOCKET_IS_FAMILY(addr, AF_INET))&&
> +        ((virSocketAddrBroadcastByPrefix(addr, prefix,&broadcast)<  0) ||
> +         !(bcaststr = virSocketFormatAddr(&broadcast)))) {
> +        goto cleanup;
> +    }
>       cmd = virCommandNew(IP_PATH);
>       virCommandAddArgList(cmd, "addr", "add", NULL);
>       virCommandAddArgFormat(cmd, "%s/%u", addrstr, prefix);
> +    if (bcaststr)
> +        virCommandAddArgList(cmd, "broadcast", bcaststr, NULL);
>       virCommandAddArgList(cmd, "dev", ifname, NULL);
>
>       if (virCommandRun(cmd, NULL)<  0)
> @@ -693,6 +702,7 @@ brAddInetAddress(brControl *ctl ATTRIBUTE_UNUSED,
>       ret = 0;
>   cleanup:
>       VIR_FREE(addrstr);
> +    VIR_FREE(bcaststr);
>       virCommandFree(cmd);
>       return ret;
>   }

ACK.
     Stefan