Re: [PATCH net-next] macvlan: pass get_ts_info and SIOC[SG]HWTSTAMP ioctl to real device

[Hangbin Liu <liuhangbin@gmail.com>]

On Tue, Apr 23, 2019 at 11:32:13AM +0200, Miroslav Lichvar wrote:
> If those values I described above were in an array called ts_map
> indexed by the RX filter enum, I think the check could just be:
> 
> 	(ts_map[old_filter] & ts_map[new_filter]) == tsmap[old_filter]
> 
> The individual bits would correspond to:
> 
> PTP_V1_L4_SYNC
> PTP_V1_L4_DELAY_REQ
> PTP_V2_L4_SYNC
> PTP_V2_L4_DELAY_REQ
> PTP_V2_L2_SYNC
> PTP_V2_L2_DELAY_REQ
> NTP_ALL
> 
> And the remaining RX filters would be combinations of those.
> 
> -- 
Hi Miroslav, Richard,

Here is a draft patch with your idea. I haven't test it and it may has some
issues. But the logic should looks like what you said. The copy_from/to_user
is a little ugly, but I haven't come up with a more gentle way.

Would you please help have a look at it and see which way we should use?
Drop SIOCSHWTSTAMP in container or add a filter on macvlan(maybe only in
container)?

Thanks
Hangbin

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index 4a6be8fab884..0f87a42fc61c 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -824,18 +824,75 @@ static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
 	return 0;
 }
 
+int check_rx_filter(unsigned int new_filter, unsigned int old_filter)
+{
+	u8 ts_map[HWTSTAMP_FILTER_NTP_ALL];
+
+	memset(ts_map, 0, sizeof(ts_map));
+
+	ts_map[HWTSTAMP_FILTER_PTP_V1_L4_SYNC - 1] = 0x01;
+	ts_map[HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ - 1] = 0x02;
+	ts_map[HWTSTAMP_FILTER_PTP_V1_L4_EVENT - 1] = 0x03;
+
+	ts_map[HWTSTAMP_FILTER_PTP_V2_L4_SYNC - 1] = 0x11;
+	ts_map[HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ - 1] = 0x12;
+	ts_map[HWTSTAMP_FILTER_PTP_V2_L4_EVENT - 1] = 0x13;
+
+	ts_map[HWTSTAMP_FILTER_PTP_V2_SYNC - 1] = 0x31;
+	ts_map[HWTSTAMP_FILTER_PTP_V2_DELAY_REQ - 1] = 0x32;
+	ts_map[HWTSTAMP_FILTER_PTP_V2_EVENT - 1] = 0x33;
+
+	ts_map[HWTSTAMP_FILTER_NTP_ALL - 1] = 0xF0;
+	ts_map[HWTSTAMP_FILTER_ALL - 1] = 0xFF;
+
+	if ((ts_map[new_filter] & ts_map[old_filter]) == ts_map[old_filter])
+		return 0;
+	else
+		return -EACCES;
+}
+
 static int macvlan_do_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 {
 	struct net_device *real_dev = macvlan_dev_real_dev(dev);
 	const struct net_device_ops *ops = real_dev->netdev_ops;
-	struct ifreq ifrr;
+	unsigned int old_filter, new_filter, new_tx_type;
+	struct hwtstamp_config new_stmpconf, old_stmpconf;
 	int err = -EOPNOTSUPP;
+	struct ifreq ifrr;
+
+	/* Get new rx_filter */
+	if (copy_from_user(&new_stmpconf, ifr->ifr_data, sizeof(new_stmpconf))) {
+		return -EFAULT;
+	} else {
+		new_tx_type = new_stmpconf.tx_type;
+		new_filter = new_stmpconf.rx_filter;
+	}
 
+	/* Get old rx_filter */
 	strncpy(ifrr.ifr_name, real_dev->name, IFNAMSIZ);
 	ifrr.ifr_ifru = ifr->ifr_ifru;
 
+	if (netif_device_present(real_dev) && ops->ndo_do_ioctl)
+		err = ops->ndo_do_ioctl(real_dev, &ifrr, SIOCGHWTSTAMP);
+
+	if (!err && copy_from_user(&old_stmpconf, ifrr.ifr_data, sizeof(old_stmpconf)))
+		old_filter = old_stmpconf.rx_filter;
+	else
+		return err;
+
+	/* Copy new data back */
+	if (copy_to_user(ifrr.ifr_data, &new_stmpconf, sizeof(new_stmpconf)))
+		return -EFAULT;
+
 	switch (cmd) {
 	case SIOCSHWTSTAMP:
+		if (new_tx_type != HWTSTAMP_TX_ON ||
+		    new_filter == HWTSTAMP_FILTER_SOME)
+			return err;
+
+		err = check_rx_filter(new_filter, old_filter);
+		if (err)
+			break;
 	case SIOCGHWTSTAMP:
 		if (netif_device_present(real_dev) && ops->ndo_do_ioctl)
 			err = ops->ndo_do_ioctl(real_dev, &ifrr, cmd);
-- 
2.19.2