[RFC PATCH net-next v3 16/21] ethtool: provide WoL information in GET_SETTINGS request

From: Michal Kubecek
Date: Mon Feb 18 2019 - 13:22:53 EST

Add information about supported and enabled wake on LAN modes into the
GET_SETTINGS reply when ETH_SETTINGS_IM_WOLINFO flag is set in the request.

The GET_SETTINGS request can be still sent by unprivileged users but in
such case the SecureOn password (if any) is not included in the reply.

Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>
---
Documentation/networking/ethtool-netlink.txt | 13 ++++-
include/uapi/linux/ethtool_netlink.h | 13 ++++-
net/ethtool/common.c | 10 ++++
net/ethtool/common.h | 1 +
net/ethtool/ioctl.c | 8 +--
net/ethtool/settings.c | 61 ++++++++++++++++++++
6 files changed, 100 insertions(+), 6 deletions(-)

diff --git a/Documentation/networking/ethtool-netlink.txt b/Documentation/networking/ethtool-netlink.txt
index 0ea7d89c6052..913df35cb762 100644
--- a/Documentation/networking/ethtool-netlink.txt
+++ b/Documentation/networking/ethtool-netlink.txt
@@ -283,6 +283,7 @@ Info mask bits meaning:

ETH_SETTINGS_IM_LINKINFO link_ksettings except link modes
ETH_SETTINGS_IM_LINKMODES link modes from link_ksettings
+ ETH_SETTINGS_IM_WOLINFO struct ethtool_wolinfo

Response contents:

@@ -298,12 +299,22 @@ Response contents:
ETHA_LINKINFO_TRANSCEIVER (u8) transceiver
ETHA_SETTINGS_LINK_MODES (bitset) device link modes
ETHA_SETTINGS_PEER_MODES (bitset) link partner link modes
+ ETHA_SETTINGS_WOL (nested) wake on LAN settings
+ ETHA_WOL_MODES (bitfield32) wake on LAN modes
+ ETHA_WOL_SOPASS (binary) SecureOn(tm) password

Most of the attributes and their values have the same meaning as matching
members of the corresponding ioctl structures. For ETHA_SETTINGS_LINK_MODES,
value represents advertised modes and mask represents supported modes.
ETHA_SETTINGS_PEER_MODES in the reply is a bit list.

+For ETHA_WOL_MODES, selector reports wake on LAN modes supported by the
+device and value enabled modes.
+
+GET_SETTINGS request is allowed for unprivileged user but ETHA_SETTINGS_SOPASS
+is only provided by kernel in response to privileged (netns CAP_NET_ADMIN)
+requests.
+
GET_SETTINGS requests allow dumps and messages in the same format as response
to them are broadcasted as notifications on change of these settings using
netlink or ioctl ethtool interface.
@@ -322,7 +333,7 @@ ETHTOOL_GSET ETHNL_CMD_GET_SETTINGS
ETHTOOL_SSET n/a
ETHTOOL_GDRVINFO ETHNL_CMD_GET_INFO
ETHTOOL_GREGS n/a
-ETHTOOL_GWOL n/a
+ETHTOOL_GWOL ETHNL_CMD_GET_SETTINGS
ETHTOOL_SWOL n/a
ETHTOOL_GMSGLVL n/a
ETHTOOL_SMSGLVL n/a
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 4e1fa4a06aac..ce9d6b48f814 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -201,6 +201,7 @@ enum {
ETHA_SETTINGS_LINK_INFO, /* nested */
ETHA_SETTINGS_LINK_MODES, /* bitset */
ETHA_SETTINGS_PEER_MODES, /* bitset */
+ ETHA_SETTINGS_WOL, /* nested */

__ETHA_SETTINGS_CNT,
ETHA_SETTINGS_MAX = (__ETHA_SETTINGS_CNT - 1)
@@ -208,8 +209,9 @@ enum {

#define ETH_SETTINGS_IM_LINKINFO 0x01
#define ETH_SETTINGS_IM_LINKMODES 0x02
+#define ETH_SETTINGS_IM_WOLINFO 0x04

-#define ETH_SETTINGS_IM_ALL 0x03
+#define ETH_SETTINGS_IM_ALL 0x07

enum {
ETHA_LINKINFO_UNSPEC,
@@ -226,6 +228,15 @@ enum {
ETHA_LINKINFO_MAX = (__ETHA_LINKINFO_CNT - 1)
};

+enum {
+ ETHA_WOL_UNSPEC,
+ ETHA_WOL_MODES, /* bitfield32 */
+ ETHA_WOL_SOPASS, /* binary */
+
+ __ETHA_WOL_CNT,
+ ETHA_WOL_MAX = (__ETHA_WOL_CNT - 1)
+};
+
/* generic netlink info */
#define ETHTOOL_GENL_NAME "ethtool"
#define ETHTOOL_GENL_VERSION 1
diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index 3316e9e403c9..9fba57f554dd 100644
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -207,3 +207,13 @@ convert_legacy_settings_to_link_ksettings(
= legacy_settings->eth_tp_mdix_ctrl;
return retval;
}
+
+int __ethtool_get_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
+{
+ if (!dev->ethtool_ops->get_wol)
+ return -EOPNOTSUPP;
+
+ dev->ethtool_ops->get_wol(dev, wol);
+
+ return 0;
+}
diff --git a/net/ethtool/common.h b/net/ethtool/common.h
index 7a3e0b10e69a..ed3f1ca54660 100644
--- a/net/ethtool/common.h
+++ b/net/ethtool/common.h
@@ -17,6 +17,7 @@ phy_tunable_strings[__ETHTOOL_PHY_TUNABLE_COUNT][ETH_GSTRING_LEN];

int __ethtool_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info);
int __ethtool_get_ts_info(struct net_device *dev, struct ethtool_ts_info *info);
+int __ethtool_get_wol(struct net_device *dev, struct ethtool_wolinfo *wol);

bool convert_legacy_settings_to_link_ksettings(
struct ethtool_link_ksettings *link_ksettings,
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 5e878cf6f418..945eaf551a4c 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -1230,11 +1230,11 @@ static int ethtool_reset(struct net_device *dev, char __user *useraddr)
static int ethtool_get_wol(struct net_device *dev, char __user *useraddr)
{
struct ethtool_wolinfo wol = { .cmd = ETHTOOL_GWOL };
+ int rc;

- if (!dev->ethtool_ops->get_wol)
- return -EOPNOTSUPP;
-
- dev->ethtool_ops->get_wol(dev, &wol);
+ rc = __ethtool_get_wol(dev, &wol);
+ if (rc < 0)
+ return rc;

if (copy_to_user(useraddr, &wol, sizeof(wol)))
return -EFAULT;
diff --git a/net/ethtool/settings.c b/net/ethtool/settings.c
index 4f2858fe1a7d..d296625edb2b 100644
--- a/net/ethtool/settings.c
+++ b/net/ethtool/settings.c
@@ -6,11 +6,13 @@

struct settings_data {
struct common_req_info reqinfo_base;
+ bool privileged;

/* everything below here will be reset for each device in dumps */
struct common_reply_data repdata_base;
struct ethtool_link_ksettings ksettings;
struct ethtool_link_settings *lsettings;
+ struct ethtool_wolinfo wolinfo;
bool lpm_empty;
};

@@ -22,15 +24,20 @@ static const struct nla_policy get_settings_policy[ETHA_SETTINGS_MAX + 1] = {
[ETHA_SETTINGS_LINK_INFO] = { .type = NLA_REJECT },
[ETHA_SETTINGS_LINK_MODES] = { .type = NLA_REJECT },
[ETHA_SETTINGS_PEER_MODES] = { .type = NLA_REJECT },
+ [ETHA_SETTINGS_WOL] = { .type = NLA_REJECT },
};

static int parse_settings(struct common_req_info *req_info,
struct sk_buff *skb, struct genl_info *info,
const struct nlmsghdr *nlhdr)
{
+ struct settings_data *data =
+ container_of(req_info, struct settings_data, reqinfo_base);
struct nlattr *tb[ETHA_SETTINGS_MAX + 1];
int ret;

+ data->privileged = ethnl_is_privileged(skb);
+
ret = genlmsg_parse(nlhdr, &ethtool_genl_family, tb,
ETHA_SETTINGS_MAX, get_settings_policy,
info ? info->extack : NULL);
@@ -68,6 +75,16 @@ static int ethnl_get_link_ksettings(struct genl_info *info,
return ret;
}

+static int ethnl_get_wol(struct genl_info *info, struct net_device *dev,
+ struct ethtool_wolinfo *wolinfo)
+{
+ int ret = __ethtool_get_wol(dev, wolinfo);
+
+ if (ret < 0)
+ ETHNL_SET_ERRMSG(info, "failed to retrieve wol info");
+ return ret;
+}
+
static int prepare_settings(struct common_req_info *req_info,
struct genl_info *info)
{
@@ -100,6 +117,11 @@ static int prepare_settings(struct common_req_info *req_info,
ethnl_bitmap_to_u32(data->ksettings.link_modes.lp_advertising,
__ETHTOOL_LINK_MODE_MASK_NWORDS);
}
+ if (req_mask & ETH_SETTINGS_IM_WOLINFO) {
+ ret = ethnl_get_wol(info, dev, &data->wolinfo);
+ if (ret < 0)
+ req_mask &= ~ETH_SETTINGS_IM_WOLINFO;
+ }
ethnl_after_ops(dev);

data->repdata_base.info_mask = req_mask;
@@ -147,6 +169,12 @@ static int link_modes_size(const struct ethtool_link_ksettings *ksettings,
return len;
}

+static int wol_size(void)
+{
+ return nla_total_size(nla_total_size(sizeof(struct nla_bitfield32)) +
+ nla_total_size(SOPASS_MAX));
+}
+
/* To keep things simple, reserve space for some attributes which may not
* be added to the message (e.g. ETHA_SETTINGS_SOPASS); therefore the length
* returned may be bigger than the actual length of the message sent
@@ -168,6 +196,8 @@ static int settings_size(const struct common_req_info *req_info)
return ret;
len += ret;
}
+ if (info_mask & ETH_SETTINGS_IM_WOLINFO)
+ len += wol_size();

return len;
}
@@ -227,6 +257,32 @@ static int fill_link_modes(struct sk_buff *skb,
return 0;
}

+static int fill_wolinfo(struct sk_buff *skb,
+ const struct ethtool_wolinfo *wolinfo, bool privileged)
+{
+ struct nlattr *nest = ethnl_nest_start(skb, ETHA_SETTINGS_WOL);
+
+ if (!nest)
+ return -EMSGSIZE;
+ if (nla_put_bitfield32(skb, ETHA_WOL_MODES, wolinfo->wolopts,
+ wolinfo->supported))
+ goto err;
+ /* ioctl() restricts read access to wolinfo but the actual
+ * reason is to hide sopass from unprivileged users; netlink
+ * can show wol modes without sopass
+ */
+ if (privileged &&
+ nla_put(skb, ETHA_WOL_SOPASS, sizeof(wolinfo->sopass),
+ wolinfo->sopass))
+ goto err;
+ nla_nest_end(skb, nest);
+ return 0;
+
+err:
+ nla_nest_cancel(skb, nest);
+ return -EMSGSIZE;
+}
+
static int fill_settings(struct sk_buff *skb,
const struct common_req_info *req_info)
{
@@ -247,6 +303,11 @@ static int fill_settings(struct sk_buff *skb,
if (ret < 0)
return ret;
}
+ if (info_mask & ETH_SETTINGS_IM_WOLINFO) {
+ ret = fill_wolinfo(skb, &data->wolinfo, data->privileged);
+ if (ret < 0)
+ return ret;
+ }

return 0;
}
--
2.20.1