nl80211/cfg80211/mac80211: add NL80211_CMD_GET_MESH_SETUP

PATCH/RFC Bob Copeland 3 participants 8 messages Dec 14, 2012 – Jan 3, 2013

Subsystems (2)

mac80211 802.11 (including cfg80211/NL80211)

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Bob Copeland

author

2012-12-14 15:15 UTC #0 lore raw

Add a new netlink call to get the parameters used at join time for the mesh. This provides a way for userspace to get some basic mesh properties that are otherwise unavailable, such as the meshid and (eventually) configured dtim and beacon values.

Signed-off-by Bob Copeland <[email protected]>

---
We can currently return the config values in GET_MESH_CONFIG but not the fixed join-time values.

My use case is to have a way to get the locally configured dtim and beacon interval, once Marco's patches are in (obviously not handled yet in this patch). Note the local values might be different from peer mesh STAs' settings.

Thomas suggested a general GET_MESH_SETUP would be good to also allow userspace to get the meshid and to know if mesh is running without doing a bogus SET_MESH_CONFIG.

Presumably, once someone implements beacon collision avoidance, I'd rather have the current dtim/beacon_int values, which isn't really setup anymore, but maybe we don't care so much.

Thoughts?

 include/net/cfg80211.h       |    3 ++
 include/uapi/linux/nl80211.h |    5 +++
 net/mac80211/cfg.c           |   30 ++++++++++++++++
 net/wireless/nl80211.c       |   78 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 116 insertions(+)

include/net/cfg80211.h +3 -0

index 8e6a6b7..51386b8 100644
@@ -1833,6 +1833,9 @@ struct cfg80211_ops {
 	int	(*update_mesh_config)(struct wiphy *wiphy,
 				      struct net_device *dev, u32 mask,
 				      const struct mesh_config *nconf);
+	int	(*get_mesh_setup)(struct wiphy *wiphy,
+				  struct net_device *dev,
+				  struct mesh_setup *setup);
 	int	(*join_mesh)(struct wiphy *wiphy, struct net_device *dev,
 			     const struct mesh_config *conf,
 			     const struct mesh_setup *setup);

include/uapi/linux/nl80211.h +5 -0

index e3e19f8..3974a92 100644
@@ -586,6 +586,9 @@
  * @NL80211_CMD_SET_MCAST_RATE: Change the rate used to send multicast frames
  *	for IBSS or MESH vif.
  *
+ * @NL80211_CMD_GET_MESH_SETUP: Retrieve mesh properties that are set at
+ *      mesh join time, for the interface identified by %NL80211_ATTR_IFINDEX.
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */

@@ -736,6 +739,8 @@ enum nl80211_commands {
 
 	NL80211_CMD_SET_MCAST_RATE,
 
+	NL80211_CMD_GET_MESH_SETUP,
+
 	/* add new commands above here */
 
 	/* used to define NL80211_CMD_MAX below */

net/mac80211/cfg.c +30 -0

index 5c61677..36e9c97 100644
@@ -1616,6 +1616,35 @@ static int copy_mesh_setup(struct ieee80211_if_mesh *ifmsh,
 	return 0;
 }
 
+static int ieee80211_get_mesh_setup(struct wiphy *wiphy,
+				    struct net_device *dev,
+				    struct mesh_setup *setup)
+{
+	struct ieee80211_sub_if_data *sdata;
+	struct ieee80211_if_mesh *ifmsh;
+
+	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	ifmsh = &sdata->u.mesh;
+
+	if (!ifmsh->mesh_id_len)
+		return -ENOLINK;
+
+	setup->mesh_id = ifmsh->mesh_id;
+	setup->mesh_id_len = ifmsh->mesh_id_len;
+	setup->sync_method = ifmsh->mesh_sp_id;
+	setup->path_sel_proto = ifmsh->mesh_pp_id;
+	setup->path_metric = ifmsh->mesh_pm_id;
+	setup->is_authenticated = ifmsh->security & IEEE80211_MESH_SEC_AUTHED;
+	setup->is_secure = ifmsh->security & IEEE80211_MESH_SEC_SECURED;
+	setup->ie = ifmsh->ie;
+	setup->ie_len = ifmsh->ie_len;
+
+	memcpy(setup->mcast_rate, sdata->vif.bss_conf.mcast_rate,
+		sizeof(sdata->vif.bss_conf.mcast_rate));
+	return 0;
+}
+
+
 static int ieee80211_update_mesh_config(struct wiphy *wiphy,
 					struct net_device *dev, u32 mask,
 					const struct mesh_config *nconf)

@@ -3206,6 +3235,7 @@ struct cfg80211_ops mac80211_config_ops = {
 	.dump_mpath = ieee80211_dump_mpath,
 	.update_mesh_config = ieee80211_update_mesh_config,
 	.get_mesh_config = ieee80211_get_mesh_config,
+	.get_mesh_setup = ieee80211_get_mesh_setup,
 	.join_mesh = ieee80211_join_mesh,
 	.leave_mesh = ieee80211_leave_mesh,
 #endif

net/wireless/nl80211.c +78 -0

90 lines not on this page · raw message

Signature · 4 lines

1.7.10.4

-- 
Bob Copeland %% www.bobcopeland.com

Javier Cardona

2012-12-14 18:17 UTC #1 lore raw

Bob,

Quoted 7 lines · Bob Copeland

Add a new netlink call to get the parameters used at join time for the mesh. This provides a way for userspace to get some basic mesh properties that are otherwise unavailable, such as the meshid and (eventually) configured dtim and beacon values.
Signed-off-by Bob Copeland <[email protected]>

This would be very useful, yes. Just one minor suggestion below...

Quoted 79 lines

---
We can currently return the config values in GET_MESH_CONFIG but not the fixed join-time values.

Thomas suggested a general GET_MESH_SETUP would be good to also allow userspace to get the meshid and to know if mesh is running without doing a bogus SET_MESH_CONFIG.

Presumably, once someone implements beacon collision avoidance, I'd rather have the current dtim/beacon_int values, which isn't really setup anymore, but maybe we don't care so much.

Thoughts?

 include/net/cfg80211.h       |    3 ++
 include/uapi/linux/nl80211.h |    5 +++
 net/mac80211/cfg.c           |   30 ++++++++++++++++
 net/wireless/nl80211.c       |   78 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 116 insertions(+)

include/net/cfg80211.h +3 -0

index 8e6a6b7..51386b8 100644
@@ -1833,6 +1833,9 @@ struct cfg80211_ops {
        int     (*update_mesh_config)(struct wiphy *wiphy,
                                      struct net_device *dev, u32 mask,
                                      const struct mesh_config *nconf);
+       int     (*get_mesh_setup)(struct wiphy *wiphy,
+                                 struct net_device *dev,
+                                 struct mesh_setup *setup);
        int     (*join_mesh)(struct wiphy *wiphy, struct net_device *dev,
                             const struct mesh_config *conf,
                             const struct mesh_setup *setup);

include/uapi/linux/nl80211.h +5 -0

index e3e19f8..3974a92 100644
@@ -586,6 +586,9 @@
  * @NL80211_CMD_SET_MCAST_RATE: Change the rate used to send multicast frames
  *     for IBSS or MESH vif.
  *
+ * @NL80211_CMD_GET_MESH_SETUP: Retrieve mesh properties that are set at
+ *      mesh join time, for the interface identified by %NL80211_ATTR_IFINDEX.
+ *
  * @NL80211_CMD_MAX: highest used command number
  * @__NL80211_CMD_AFTER_LAST: internal use
  */

@@ -736,6 +739,8 @@ enum nl80211_commands {
 
        NL80211_CMD_SET_MCAST_RATE,
 
+       NL80211_CMD_GET_MESH_SETUP,
+
        /* add new commands above here */
 
        /* used to define NL80211_CMD_MAX below */

net/mac80211/cfg.c +9 -0

index 5c61677..36e9c97 100644
@@ -1616,6 +1616,35 @@ static int copy_mesh_setup(struct ieee80211_if_mesh *ifmsh,
        return 0;
 }
 
+static int ieee80211_get_mesh_setup(struct wiphy *wiphy,
+                                   struct net_device *dev,
+                                   struct mesh_setup *setup)
+{
+       struct ieee80211_sub_if_data *sdata;
+       struct ieee80211_if_mesh *ifmsh;
+
+       sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+       ifmsh = &sdata->u.mesh;

net/mac80211/cfg.c static int copy_mesh_setup(struct ieee80211_if_mesh *ifmsh, · line 1637

Quoted 10 lines

net/mac80211/cfg.c +10 -0

+
+       if (!ifmsh->mesh_id_len)
+               return -ENOLINK;
+
+       setup->mesh_id = ifmsh->mesh_id;
+       setup->mesh_id_len = ifmsh->mesh_id_len;
+       setup->sync_method = ifmsh->mesh_sp_id;
+       setup->path_sel_proto = ifmsh->mesh_pp_id;
+       setup->path_metric = ifmsh->mesh_pm_id;
+       setup->is_authenticated = ifmsh->security & IEEE80211_MESH_SEC_AUTHED;

+ setup->is_authenticated = !!(ifmsh->security &
IEEE80211_MESH_SEC_AUTHED));

i.e. to force the value to be 0 or 1.

net/mac80211/cfg.c static int copy_mesh_setup(struct ieee80211_if_mesh *ifmsh, · line 1638

Quoted 1 line

net/mac80211/cfg.c +1 -0

+       setup->is_secure = ifmsh->security & IEEE80211_MESH_SEC_SECURED;

+ setup->is_secure = !!(ifmsh->security & IEEE80211_MESH_SEC_SECURED);

same.

Quoted 125 lines

net/mac80211/cfg.c +10 -0

+       setup->ie = ifmsh->ie;
+       setup->ie_len = ifmsh->ie_len;
+
+       memcpy(setup->mcast_rate, sdata->vif.bss_conf.mcast_rate,
+               sizeof(sdata->vif.bss_conf.mcast_rate));
+       return 0;
+}
+
+
 static int ieee80211_update_mesh_config(struct wiphy *wiphy,
                                        struct net_device *dev, u32 mask,
                                        const struct mesh_config *nconf)

@@ -3206,6 +3235,7 @@ struct cfg80211_ops mac80211_config_ops = {
        .dump_mpath = ieee80211_dump_mpath,
        .update_mesh_config = ieee80211_update_mesh_config,
        .get_mesh_config = ieee80211_get_mesh_config,
+       .get_mesh_setup = ieee80211_get_mesh_setup,
        .join_mesh = ieee80211_join_mesh,
        .leave_mesh = ieee80211_leave_mesh,
 #endif

net/wireless/nl80211.c +78 -1

index f45706a..84a6a45 100644
@@ -3921,6 +3921,76 @@ static int nl80211_get_mesh_config(struct sk_buff *skb,
        return -ENOBUFS;
 }
 
+static int nl80211_get_mesh_setup(struct sk_buff *skb,
+                                 struct genl_info *info)
+{
+       struct cfg80211_registered_device *rdev = info->user_ptr[0];
+       struct net_device *dev = info->user_ptr[1];
+       struct wireless_dev *wdev = dev->ieee80211_ptr;
+       struct mesh_setup setup;
+       int err = 0;
+       void *hdr;
+       struct nlattr *pinfoattr;
+       struct sk_buff *msg;
+
+       if (wdev->iftype != NL80211_IFTYPE_MESH_POINT)
+               return -EOPNOTSUPP;
+
+       if (!rdev->ops->get_mesh_setup)
+               return -EOPNOTSUPP;
+
+       wdev_lock(wdev);
+       err = rdev->ops->get_mesh_setup(&rdev->wiphy, dev, &setup);
+       if (err)
+               goto out;
+
+       msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+       if (!msg) {
+               err = -ENOMEM;
+               goto out;
+       }
+
+       hdr = nl80211hdr_put(msg, info->snd_portid, info->snd_seq, 0,
+                            NL80211_CMD_GET_MESH_SETUP);
+       if (!hdr)
+               goto out_err;
+
+       if (nla_put(msg, NL80211_ATTR_MESH_ID, setup.mesh_id_len,
+                   setup.mesh_id))
+               goto nla_put_failure;
+
+       pinfoattr = nla_nest_start(msg, NL80211_ATTR_MESH_SETUP);
+       if (!pinfoattr)
+               goto nla_put_failure;
+
+       if (nla_put_u8(msg, NL80211_MESH_SETUP_ENABLE_VENDOR_SYNC,
+                      setup.sync_method) ||
+           nla_put_u8(msg, NL80211_MESH_SETUP_ENABLE_VENDOR_PATH_SEL,
+                      setup.path_sel_proto) ||
+           nla_put_u8(msg, NL80211_MESH_SETUP_ENABLE_VENDOR_METRIC,
+                      setup.path_metric) ||
+           (setup.is_authenticated &&
+            nla_put_flag(msg, NL80211_MESH_SETUP_USERSPACE_AUTH)) ||
+           (setup.is_secure &&
+            nla_put_flag(msg, NL80211_MESH_SETUP_USERSPACE_AMPE)))
+               goto nla_put_failure;
+
+       nla_nest_end(msg, pinfoattr);
+       genlmsg_end(msg, hdr);
+
+       err = genlmsg_reply(msg, info);
+       goto out;
+
+ nla_put_failure:
+       genlmsg_cancel(msg, hdr);
+ out_err:
+       nlmsg_free(msg);
+       err = -ENOBUFS;
+ out:
+       wdev_unlock(wdev);
+       return err;
+}
+
 static const struct nla_policy nl80211_meshconf_params_policy[NL80211_MESHCONF_ATTR_MAX+1] = {
        [NL80211_MESHCONF_RETRY_TIMEOUT] = { .type = NLA_U16 },
        [NL80211_MESHCONF_CONFIRM_TIMEOUT] = { .type = NLA_U16 },

@@ -7784,6 +7854,14 @@ static struct genl_ops nl80211_ops[] = {
                .internal_flags = NL80211_FLAG_NEED_NETDEV |
                                  NL80211_FLAG_NEED_RTNL,
        },
+       {
+               .cmd = NL80211_CMD_GET_MESH_SETUP,
+               .doit = nl80211_get_mesh_setup,
+               .policy = nl80211_policy,
+               /* can be retrieved by unprivileged users */
+               .internal_flags = NL80211_FLAG_NEED_NETDEV_UP |
+                                 NL80211_FLAG_NEED_RTNL,
+       },
 };
 
 static struct genl_multicast_group nl80211_mlme_mcgrp = {
--

1.7.10.4

--
Bob Copeland %% www.bobcopeland.com
_______________________________________________
Devel mailing list
[email protected]
http://lists.open80211s.org/cgi-bin/mailman/listinfo/devel

Signature · 3 lines

Javier Cardona
cozybit Inc.
http://www.cozybit.com

Johannes Berg

maintainer

2012-12-14 18:59 UTC #2 lore raw

Quoted 5 lines · Javier Cardona

Quoted 1 line
+ setup->is_authenticated = ifmsh->security & IEEE80211_MESH_SEC_AUTHED;
+ setup->is_authenticated = !!(ifmsh->security &
IEEE80211_MESH_SEC_AUTHED));
i.e. to force the value to be 0 or 1.

is_authenticate is a bool, so no need, the compiler has to do it.

johannes

Bob Copeland

author

2012-12-14 19:01 UTC #3 lore raw

In reply to Javier Cardona

On Fri, Dec 14, 2012 at 10:17:24AM -0800, Javier Cardona wrote:

Thanks for the review!

Quoted 5 lines

Quoted 1 line
+ setup->is_authenticated = ifmsh->security & IEEE80211_MESH_SEC_AUTHED;
+ setup->is_authenticated = !!(ifmsh->security &
IEEE80211_MESH_SEC_AUTHED));
i.e. to force the value to be 0 or 1.

Agreed if they were ints, but in this case .is_authenticated and .is_secure are type bool, so it shouldn't make a difference, right?

Signature · 1 line

Bob Copeland %% www.bobcopeland.com

Javier Cardona

2012-12-14 19:08 UTC #4 lore raw

Quoted 4 lines · Bob Copeland

On Fri, Dec 14, 2012 at 10:17:24AM -0800, Javier Cardona wrote:
Thanks for the review!

Quoted 8 lines

Quoted 5 lines
Quoted 1 line
+ setup->is_authenticated = ifmsh->security & IEEE80211_MESH_SEC_AUTHED;
+ setup->is_authenticated = !!(ifmsh->security &
IEEE80211_MESH_SEC_AUTHED));
i.e. to force the value to be 0 or 1.
Agreed if they were ints, but in this case .is_authenticated and .is_secure are type bool, so it shouldn't make a difference, right?

Yes, you are right. Johannes pointed that out as well.

Sorry,

Javier

Quoted 7 lines

--
Bob Copeland %% www.bobcopeland.com
_______________________________________________
Devel mailing list
[email protected]
http://lists.open80211s.org/cgi-bin/mailman/listinfo/devel

Signature · 3 lines

Javier Cardona
cozybit Inc.
http://www.cozybit.com

Bob Copeland

author

2012-12-14 19:12 UTC #5 lore raw

Quoted 3 lines · Javier Cardona

Quoted 1 line
.is_secure are type bool, so it shouldn't make a difference, right?
Yes, you are right. Johannes pointed that out as well.

Dang, and he beat me by a minute according to my timestamps :)

Signature · 1 line

Bob Copeland %% www.bobcopeland.com

Johannes Berg

maintainer

2012-12-28 14:43 UTC #6 lore raw

In reply to Bob Copeland

Quoted 16 lines · Bob Copeland

Add a new netlink call to get the parameters used at join time for the mesh. This provides a way for userspace to get some basic mesh properties that are otherwise unavailable, such as the meshid and (eventually) configured dtim and beacon values.
Signed-off-by Bob Copeland <[email protected]>
---
We can currently return the config values in GET_MESH_CONFIG but not the fixed join-time values.
My use case is to have a way to get the locally configured dtim and beacon interval, once Marco's patches are in (obviously not handled yet in this patch). Note the local values might be different from peer mesh STAs' settings.

Quoted 7 lines

Thomas suggested a general GET_MESH_SETUP would be good to also allow userspace to get the meshid and to know if mesh is running without doing a bogus SET_MESH_CONFIG.
Presumably, once someone implements beacon collision avoidance, I'd rather have the current dtim/beacon_int values, which isn't really setup anymore, but maybe we don't care so much.

Seems fine, but I think you should document the latter. OTOH, maybe it should just be documented that the setup values are hints only when that is implemented ...

I guess the question is: would there be value in knowing what it was set up with vs. what it's currently doing? Maybe because if other peers go away it would fall back to the previous values?

Or maybe that just means that if the values are changed they should be returned differently?

johannes

Bob Copeland

author

2013-01-03 05:18 UTC #7 lore raw

Quoted 8 lines · Johannes Berg

Quoted 3 lines · Bob Copeland
Presumably, once someone implements beacon collision avoidance, I'd rather have the current dtim/beacon_int values, which isn't really setup anymore, but maybe we don't care so much.
Seems fine, but I think you should document the latter. OTOH, maybe it should just be documented that the setup values are hints only when that is implemented ...

I plan to look at MBCA soon, so I'll think on it a bit.

Signature · 1 line

Bob Copeland %% www.bobcopeland.com