cfg80211: add add_nan_func / del_nan_func

A NAN function can be either publish, subscribe or follow
up. Make all the necessary verifications and just pass the
request to the driver.
Allow the user space application that starts NAN to
forbid any other socket to add or remove functions.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Ayala Beker <ayala.beker@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 369 insertions, 0 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 9e9fb37087fc..0eca59ccd685 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -411,6 +411,7 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
 	[NL80211_ATTR_MU_MIMO_FOLLOW_MAC_ADDR] = { .len = ETH_ALEN },
 	[NL80211_ATTR_NAN_MASTER_PREF] = { .type = NLA_U8 },
 	[NL80211_ATTR_NAN_DUAL] = { .type = NLA_U8 },
+	[NL80211_ATTR_NAN_FUNC] = { .type = NLA_NESTED },
 };
 
 /* policy for the key attributes */
@@ -504,6 +505,39 @@ nl80211_bss_select_policy[NL80211_BSS_SELECT_ATTR_MAX + 1] = {
 	},
 };
 
+/* policy for NAN function attributes */
+static const struct nla_policy
+nl80211_nan_func_policy[NL80211_NAN_FUNC_ATTR_MAX + 1] = {
+	[NL80211_NAN_FUNC_TYPE] = { .type = NLA_U8 },
+	[NL80211_NAN_FUNC_SERVICE_ID] = { .type = NLA_BINARY,
+				    .len = NL80211_NAN_FUNC_SERVICE_ID_LEN },
+	[NL80211_NAN_FUNC_PUBLISH_TYPE] = { .type = NLA_U8 },
+	[NL80211_NAN_FUNC_PUBLISH_BCAST] = { .type = NLA_FLAG },
+	[NL80211_NAN_FUNC_SUBSCRIBE_ACTIVE] = { .type = NLA_FLAG },
+	[NL80211_NAN_FUNC_FOLLOW_UP_ID] = { .type = NLA_U8 },
+	[NL80211_NAN_FUNC_FOLLOW_UP_REQ_ID] = { .type = NLA_U8 },
+	[NL80211_NAN_FUNC_FOLLOW_UP_DEST] = { .len = ETH_ALEN },
+	[NL80211_NAN_FUNC_CLOSE_RANGE] = { .type = NLA_FLAG },
+	[NL80211_NAN_FUNC_TTL] = { .type = NLA_U32 },
+	[NL80211_NAN_FUNC_SERVICE_INFO] = { .type = NLA_BINARY,
+			.len = NL80211_NAN_FUNC_SERVICE_SPEC_INFO_MAX_LEN },
+	[NL80211_NAN_FUNC_SRF] = { .type = NLA_NESTED },
+	[NL80211_NAN_FUNC_RX_MATCH_FILTER] = { .type = NLA_NESTED },
+	[NL80211_NAN_FUNC_TX_MATCH_FILTER] = { .type = NLA_NESTED },
+	[NL80211_NAN_FUNC_INSTANCE_ID] = { .type = NLA_U8 },
+	[NL80211_NAN_FUNC_TERM_REASON] = { .type = NLA_U8 },
+};
+
+/* policy for Service Response Filter attributes */
+static const struct nla_policy
+nl80211_nan_srf_policy[NL80211_NAN_SRF_ATTR_MAX + 1] = {
+	[NL80211_NAN_SRF_INCLUDE] = { .type = NLA_FLAG },
+	[NL80211_NAN_SRF_BF] = { .type = NLA_BINARY,
+				 .len =  NL80211_NAN_FUNC_SRF_MAX_LEN },
+	[NL80211_NAN_SRF_BF_IDX] = { .type = NLA_U8 },
+	[NL80211_NAN_SRF_MAC_ADDRS] = { .type = NLA_NESTED },
+};
+
 static int nl80211_prepare_wdev_dump(struct sk_buff *skb,
 				     struct netlink_callback *cb,
 				     struct cfg80211_registered_device **rdev,
@@ -10566,6 +10600,325 @@ static int nl80211_stop_nan(struct sk_buff *skb, struct genl_info *info)
 	return 0;
 }
 
+static int validate_nan_filter(struct nlattr *filter_attr)
+{
+	struct nlattr *attr;
+	int len = 0, n_entries = 0, rem;
+
+	nla_for_each_nested(attr, filter_attr, rem) {
+		len += nla_len(attr);
+		n_entries++;
+	}
+
+	if (len >= U8_MAX)
+		return -EINVAL;
+
+	return n_entries;
+}
+
+static int handle_nan_filter(struct nlattr *attr_filter,
+			     struct cfg80211_nan_func *func,
+			     bool tx)
+{
+	struct nlattr *attr;
+	int n_entries, rem, i;
+	struct cfg80211_nan_func_filter *filter;
+
+	n_entries = validate_nan_filter(attr_filter);
+	if (n_entries < 0)
+		return n_entries;
+
+	BUILD_BUG_ON(sizeof(*func->rx_filters) != sizeof(*func->tx_filters));
+
+	filter = kcalloc(n_entries, sizeof(*func->rx_filters), GFP_KERNEL);
+	if (!filter)
+		return -ENOMEM;
+
+	i = 0;
+	nla_for_each_nested(attr, attr_filter, rem) {
+		filter[i].filter = kmemdup(nla_data(attr), nla_len(attr),
+					   GFP_KERNEL);
+		filter[i].len = nla_len(attr);
+		i++;
+	}
+	if (tx) {
+		func->num_tx_filters = n_entries;
+		func->tx_filters = filter;
+	} else {
+		func->num_rx_filters = n_entries;
+		func->rx_filters = filter;
+	}
+
+	return 0;
+}
+
+static int nl80211_nan_add_func(struct sk_buff *skb,
+				struct genl_info *info)
+{
+	struct cfg80211_registered_device *rdev = info->user_ptr[0];
+	struct wireless_dev *wdev = info->user_ptr[1];
+	struct nlattr *tb[NUM_NL80211_NAN_FUNC_ATTR], *func_attr;
+	struct cfg80211_nan_func *func;
+	struct sk_buff *msg = NULL;
+	void *hdr = NULL;
+	int err = 0;
+
+	if (wdev->iftype != NL80211_IFTYPE_NAN)
+		return -EOPNOTSUPP;
+
+	if (!wdev->nan_started)
+		return -ENOTCONN;
+
+	if (!info->attrs[NL80211_ATTR_NAN_FUNC])
+		return -EINVAL;
+
+	if (wdev->owner_nlportid &&
+	    wdev->owner_nlportid != info->snd_portid)
+		return -ENOTCONN;
+
+	err = nla_parse(tb, NL80211_NAN_FUNC_ATTR_MAX,
+			nla_data(info->attrs[NL80211_ATTR_NAN_FUNC]),
+			nla_len(info->attrs[NL80211_ATTR_NAN_FUNC]),
+			nl80211_nan_func_policy);
+	if (err)
+		return err;
+
+	func = kzalloc(sizeof(*func), GFP_KERNEL);
+	if (!func)
+		return -ENOMEM;
+
+	func->cookie = wdev->wiphy->cookie_counter++;
+
+	if (!tb[NL80211_NAN_FUNC_TYPE] ||
+	    nla_get_u8(tb[NL80211_NAN_FUNC_TYPE]) > NL80211_NAN_FUNC_MAX_TYPE) {
+		err = -EINVAL;
+		goto out;
+	}
+
+
+	func->type = nla_get_u8(tb[NL80211_NAN_FUNC_TYPE]);
+
+	if (!tb[NL80211_NAN_FUNC_SERVICE_ID]) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	memcpy(func->service_id, nla_data(tb[NL80211_NAN_FUNC_SERVICE_ID]),
+	       sizeof(func->service_id));
+
+	func->close_range =
+		nla_get_flag(tb[NL80211_NAN_FUNC_CLOSE_RANGE]);
+
+	if (tb[NL80211_NAN_FUNC_SERVICE_INFO]) {
+		func->serv_spec_info_len =
+			nla_len(tb[NL80211_NAN_FUNC_SERVICE_INFO]);
+		func->serv_spec_info =
+			kmemdup(nla_data(tb[NL80211_NAN_FUNC_SERVICE_INFO]),
+				func->serv_spec_info_len,
+				GFP_KERNEL);
+		if (!func->serv_spec_info) {
+			err = -ENOMEM;
+			goto out;
+		}
+	}
+
+	if (tb[NL80211_NAN_FUNC_TTL])
+		func->ttl = nla_get_u32(tb[NL80211_NAN_FUNC_TTL]);
+
+	switch (func->type) {
+	case NL80211_NAN_FUNC_PUBLISH:
+		if (!tb[NL80211_NAN_FUNC_PUBLISH_TYPE]) {
+			err = -EINVAL;
+			goto out;
+		}
+
+		func->publish_type =
+			nla_get_u8(tb[NL80211_NAN_FUNC_PUBLISH_TYPE]);
+		func->publish_bcast =
+			nla_get_flag(tb[NL80211_NAN_FUNC_PUBLISH_BCAST]);
+
+		if ((!(func->publish_type & NL80211_NAN_SOLICITED_PUBLISH)) &&
+			func->publish_bcast) {
+			err = -EINVAL;
+			goto out;
+		}
+		break;
+	case NL80211_NAN_FUNC_SUBSCRIBE:
+		func->subscribe_active =
+			nla_get_flag(tb[NL80211_NAN_FUNC_SUBSCRIBE_ACTIVE]);
+		break;
+	case NL80211_NAN_FUNC_FOLLOW_UP:
+		if (!tb[NL80211_NAN_FUNC_FOLLOW_UP_ID] ||
+		    !tb[NL80211_NAN_FUNC_FOLLOW_UP_REQ_ID]) {
+			err = -EINVAL;
+			goto out;
+		}
+
+		func->followup_id =
+			nla_get_u8(tb[NL80211_NAN_FUNC_FOLLOW_UP_ID]);
+		func->followup_reqid =
+			nla_get_u8(tb[NL80211_NAN_FUNC_FOLLOW_UP_REQ_ID]);
+		memcpy(func->followup_dest.addr,
+		       nla_data(tb[NL80211_NAN_FUNC_FOLLOW_UP_DEST]),
+		       sizeof(func->followup_dest.addr));
+		if (func->ttl) {
+			err = -EINVAL;
+			goto out;
+		}
+		break;
+	default:
+		err = -EINVAL;
+		goto out;
+	}
+
+	if (tb[NL80211_NAN_FUNC_SRF]) {
+		struct nlattr *srf_tb[NUM_NL80211_NAN_SRF_ATTR];
+
+		err = nla_parse(srf_tb, NL80211_NAN_SRF_ATTR_MAX,
+				nla_data(tb[NL80211_NAN_FUNC_SRF]),
+				nla_len(tb[NL80211_NAN_FUNC_SRF]), NULL);
+		if (err)
+			goto out;
+
+		func->srf_include =
+			nla_get_flag(srf_tb[NL80211_NAN_SRF_INCLUDE]);
+
+		if (srf_tb[NL80211_NAN_SRF_BF]) {
+			if (srf_tb[NL80211_NAN_SRF_MAC_ADDRS] ||
+			    !srf_tb[NL80211_NAN_SRF_BF_IDX]) {
+				err = -EINVAL;
+				goto out;
+			}
+
+			func->srf_bf_len =
+				nla_len(srf_tb[NL80211_NAN_SRF_BF]);
+			func->srf_bf =
+				kmemdup(nla_data(srf_tb[NL80211_NAN_SRF_BF]),
+					func->srf_bf_len, GFP_KERNEL);
+			if (!func->srf_bf) {
+				err = -ENOMEM;
+				goto out;
+			}
+
+			func->srf_bf_idx =
+				nla_get_u8(srf_tb[NL80211_NAN_SRF_BF_IDX]);
+		} else {
+			struct nlattr *attr, *mac_attr =
+				srf_tb[NL80211_NAN_SRF_MAC_ADDRS];
+			int n_entries, rem, i = 0;
+
+			if (!mac_attr) {
+				err = -EINVAL;
+				goto out;
+			}
+
+			n_entries = validate_acl_mac_addrs(mac_attr);
+			if (n_entries <= 0) {
+				err = -EINVAL;
+				goto out;
+			}
+
+			func->srf_num_macs = n_entries;
+			func->srf_macs =
+				kzalloc(sizeof(*func->srf_macs) * n_entries,
+					GFP_KERNEL);
+			if (!func->srf_macs) {
+				err = -ENOMEM;
+				goto out;
+			}
+
+			nla_for_each_nested(attr, mac_attr, rem)
+				memcpy(func->srf_macs[i++].addr, nla_data(attr),
+				       sizeof(*func->srf_macs));
+		}
+	}
+
+	if (tb[NL80211_NAN_FUNC_TX_MATCH_FILTER]) {
+		err = handle_nan_filter(tb[NL80211_NAN_FUNC_TX_MATCH_FILTER],
+					func, true);
+		if (err)
+			goto out;
+	}
+
+	if (tb[NL80211_NAN_FUNC_RX_MATCH_FILTER]) {
+		err = handle_nan_filter(tb[NL80211_NAN_FUNC_RX_MATCH_FILTER],
+					func, false);
+		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_ADD_NAN_FUNCTION);
+	/* This can't really happen - we just allocated 4KB */
+	if (WARN_ON(!hdr)) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = rdev_add_nan_func(rdev, wdev, func);
+out:
+	if (err < 0) {
+		cfg80211_free_nan_func(func);
+		nlmsg_free(msg);
+		return err;
+	}
+
+	/* propagate the instance id and cookie to userspace  */
+	if (nla_put_u64_64bit(msg, NL80211_ATTR_COOKIE, func->cookie,
+			      NL80211_ATTR_PAD))
+		goto nla_put_failure;
+
+	func_attr = nla_nest_start(msg, NL80211_ATTR_NAN_FUNC);
+	if (!func_attr)
+		goto nla_put_failure;
+
+	if (nla_put_u8(msg, NL80211_NAN_FUNC_INSTANCE_ID,
+		       func->instance_id))
+		goto nla_put_failure;
+
+	nla_nest_end(msg, func_attr);
+
+	genlmsg_end(msg, hdr);
+	return genlmsg_reply(msg, info);
+
+nla_put_failure:
+	nlmsg_free(msg);
+	return -ENOBUFS;
+}
+
+static int nl80211_nan_del_func(struct sk_buff *skb,
+			       struct genl_info *info)
+{
+	struct cfg80211_registered_device *rdev = info->user_ptr[0];
+	struct wireless_dev *wdev = info->user_ptr[1];
+	u64 cookie;
+
+	if (wdev->iftype != NL80211_IFTYPE_NAN)
+		return -EOPNOTSUPP;
+
+	if (!wdev->nan_started)
+		return -ENOTCONN;
+
+	if (!info->attrs[NL80211_ATTR_COOKIE])
+		return -EINVAL;
+
+	if (wdev->owner_nlportid &&
+	    wdev->owner_nlportid != info->snd_portid)
+		return -ENOTCONN;
+
+	cookie = nla_get_u64(info->attrs[NL80211_ATTR_COOKIE]);
+
+	rdev_del_nan_func(rdev, wdev, cookie);
+
+	return 0;
+}
+
 static int nl80211_get_protocol_features(struct sk_buff *skb,
 					 struct genl_info *info)
 {
@@ -11924,6 +12277,22 @@ static const struct genl_ops nl80211_ops[] = {
 				  NL80211_FLAG_NEED_RTNL,
 	},
 	{
+		.cmd = NL80211_CMD_ADD_NAN_FUNCTION,
+		.doit = nl80211_nan_add_func,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = NL80211_FLAG_NEED_WDEV_UP |
+				  NL80211_FLAG_NEED_RTNL,
+	},
+	{
+		.cmd = NL80211_CMD_DEL_NAN_FUNCTION,
+		.doit = nl80211_nan_del_func,
+		.policy = nl80211_policy,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = NL80211_FLAG_NEED_WDEV_UP |
+				  NL80211_FLAG_NEED_RTNL,
+	},
+	{
 		.cmd = NL80211_CMD_SET_MCAST_RATE,
 		.doit = nl80211_set_mcast_rate,
 		.policy = nl80211_policy,