Return-path: Received: from mail-bn3nam01on0041.outbound.protection.outlook.com ([104.47.33.41]:53568 "EHLO NAM01-BN3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753292AbdKIJkl (ORCPT ); Thu, 9 Nov 2017 04:40:41 -0500 From: Sergey Matyukevich To: linux-wireless@vger.kernel.org, Johannes Berg Cc: Igor Mitsyanko , Avinash Patil , Vasily Ulyanov , Sergey Matyukevich Subject: [RFC PATCH 1/2] nl80211: implement NL80211_CMD_GET_BEACON command Date: Thu, 9 Nov 2017 12:40:23 +0300 Message-Id: <20171109094024.9085-1-sergey.matyukevich.os@quantenna.com> (sfid-20171109_104132_462807_D8EFBF25) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Vasily Ulyanov Implement nl80211_get_beacon callback which returns current beacon configuration. The actual data is saved on .start_ap and .set_beacon calls. Signed-off-by: Vasily Ulyanov --- include/net/cfg80211.h | 3 + include/uapi/linux/nl80211.h | 5 +- net/wireless/nl80211.c | 220 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 227 insertions(+), 1 deletion(-) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 8b8118a7fadb..31d39e066274 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -4002,6 +4002,8 @@ struct cfg80211_cqm_config; * the user-set channel definition. * @preset_chandef: (private) Used by the internal configuration code to * track the channel to be used for AP later + * @beacon: (private) Used by the internal configuration code to track + * the user-set effective beacon data. * @bssid: (private) Used by the internal configuration code * @ssid: (private) Used by the internal configuration code * @ssid_len: (private) Used by the internal configuration code @@ -4078,6 +4080,7 @@ struct wireless_dev { struct cfg80211_internal_bss *current_bss; /* associated / joined */ struct cfg80211_chan_def preset_chandef; struct cfg80211_chan_def chandef; + struct cfg80211_beacon_data beacon; bool ibss_fixed; bool ibss_dfs_possible; diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index f882fe1f9709..e9e163bbe11a 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -279,7 +279,10 @@ * @NL80211_CMD_DEL_KEY: delete a key identified by %NL80211_ATTR_KEY_IDX * or %NL80211_ATTR_MAC. * - * @NL80211_CMD_GET_BEACON: (not used) + * @NL80211_CMD_GET_BEACON: Get beacon attributes on an access point interface. + * %NL80211_ATTR_BEACON_HEAD, %NL80211_ATTR_BEACON_TAIL, %NL80211_ATTR_IE, + * %NL80211_ATTR_IE_PROBE_RESP, NL80211_ATTR_IE_ASSOC_RESP, + * %NL80211_ATTR_PROBE_RESP will be returned if present. * @NL80211_CMD_SET_BEACON: change the beacon on an access point interface * using the %NL80211_ATTR_BEACON_HEAD and %NL80211_ATTR_BEACON_TAIL * attributes. For drivers that generate the beacon and probe responses diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index fce2cbe6a193..f03f9989efbc 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -3784,6 +3784,172 @@ static int nl80211_parse_beacon(struct nlattr *attrs[], return 0; } +static size_t nl80211_beacon_size(struct cfg80211_beacon_data *bcn) +{ + size_t size = bcn->head_len + bcn->tail_len + + bcn->beacon_ies_len + + bcn->proberesp_ies_len + + bcn->assocresp_ies_len + + bcn->probe_resp_len; + + return size; +} + +static void nl80211_free_beacon(struct cfg80211_beacon_data *bcn) +{ +#define free_and_null(member) \ + do { \ + kfree(bcn->member); \ + bcn->member = NULL; \ + bcn->member ## _len = 0; \ + } while (0) + + free_and_null(head); + free_and_null(tail); + free_and_null(beacon_ies); + free_and_null(proberesp_ies); + free_and_null(assocresp_ies); + free_and_null(probe_resp); + +#undef free_and_null +} + +static int nl80211_dup_beacon(struct cfg80211_beacon_data *dst, + struct cfg80211_beacon_data *src) +{ + memset(dst, 0, sizeof(*dst)); + +#define check_and_dup(member) \ + do { \ + if (src->member && (src->member ## _len > 0)) { \ + dst->member = kmemdup(src->member, \ + src->member ## _len, \ + GFP_KERNEL); \ + if (!dst->member) \ + goto dup_failure; \ + dst->member ## _len = src->member ## _len; \ + } \ + } while (0) + + check_and_dup(head); + check_and_dup(tail); + check_and_dup(beacon_ies); + check_and_dup(proberesp_ies); + check_and_dup(assocresp_ies); + check_and_dup(probe_resp); + +#undef dup_and_check + + return 0; + +dup_failure: + nl80211_free_beacon(dst); + return -ENOMEM; +} + +static int nl80211_merge_beacons(struct cfg80211_beacon_data *dst, + struct cfg80211_beacon_data *old, + struct cfg80211_beacon_data *new) +{ + memset(dst, 0, sizeof(*dst)); + +#define check_and_merge(member) \ + do { \ + if (new->member && (new->member ## _len > 0)) { \ + dst->member = kmemdup(new->member, \ + new->member ## _len, \ + GFP_KERNEL); \ + if (!dst->member) \ + goto dup_failure; \ + dst->member ## _len = new->member ## _len; \ + } else if (old->member && (old->member ## _len > 0)) { \ + dst->member = kmemdup(old->member, \ + old->member ## _len, \ + GFP_KERNEL); \ + if (!dst->member) \ + goto dup_failure; \ + dst->member ## _len = old->member ## _len; \ + } \ + } while (0) + + check_and_merge(head); + check_and_merge(tail); + check_and_merge(beacon_ies); + check_and_merge(proberesp_ies); + check_and_merge(assocresp_ies); + check_and_merge(probe_resp); + +#undef check_and_merge + + return 0; + +dup_failure: + nl80211_free_beacon(dst); + return -ENOMEM; +} + +static void nl80211_assign_beacon(struct cfg80211_beacon_data *dst, + struct cfg80211_beacon_data *src) +{ + nl80211_free_beacon(dst); + *dst = *src; +} + +static int nl80211_send_beacon(struct sk_buff *msg, u32 portid, + enum nl80211_commands cmd, + u32 seq, int flags, + struct cfg80211_beacon_data *bcn) +{ + void *hdr; + + hdr = nl80211hdr_put(msg, portid, seq, flags, cmd); + if (!hdr) + return -EMSGSIZE; + + if (bcn->head && (bcn->head_len > 0)) { + if (nla_put(msg, NL80211_ATTR_BEACON_HEAD, + bcn->head_len, bcn->head)) + goto nla_put_failure; + } + + if (bcn->tail && (bcn->tail_len > 0)) { + if (nla_put(msg, NL80211_ATTR_BEACON_TAIL, + bcn->tail_len, bcn->tail)) + goto nla_put_failure; + } + + if (bcn->beacon_ies && (bcn->beacon_ies_len > 0)) { + if (nla_put(msg, NL80211_ATTR_IE, + bcn->beacon_ies_len, bcn->beacon_ies)) + goto nla_put_failure; + } + + if (bcn->proberesp_ies && (bcn->proberesp_ies_len > 0)) { + if (nla_put(msg, NL80211_ATTR_IE_PROBE_RESP, + bcn->proberesp_ies_len, bcn->proberesp_ies)) + goto nla_put_failure; + } + + if (bcn->assocresp_ies && (bcn->assocresp_ies_len > 0)) { + if (nla_put(msg, NL80211_ATTR_IE_ASSOC_RESP, + bcn->assocresp_ies_len, bcn->assocresp_ies)) + goto nla_put_failure; + } + + if (bcn->probe_resp && (bcn->probe_resp_len > 0)) { + if (nla_put(msg, NL80211_ATTR_PROBE_RESP, + bcn->probe_resp_len, bcn->probe_resp)) + goto nla_put_failure; + } + + genlmsg_end(msg, hdr); + return 0; + +nla_put_failure: + genlmsg_cancel(msg, hdr); + return -EMSGSIZE; +} + static void nl80211_check_ap_rate_selectors(struct cfg80211_ap_settings *params, const u8 *rates) { @@ -3903,6 +4069,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info) struct net_device *dev = info->user_ptr[1]; struct wireless_dev *wdev = dev->ieee80211_ptr; struct cfg80211_ap_settings params; + struct cfg80211_beacon_data new_bcn; int err; if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP && @@ -4070,6 +4237,10 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info) nl80211_calculate_ap_params(¶ms); + err = nl80211_dup_beacon(&new_bcn, ¶ms.beacon); + if (err) + goto dup_failure; + wdev_lock(wdev); err = rdev_start_ap(rdev, dev, ¶ms); if (!err) { @@ -4078,20 +4249,52 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info) wdev->chandef = params.chandef; wdev->ssid_len = params.ssid_len; memcpy(wdev->ssid, params.ssid, wdev->ssid_len); + nl80211_assign_beacon(&wdev->beacon, &new_bcn); } wdev_unlock(wdev); + if (err) + nl80211_free_beacon(&new_bcn); + +dup_failure: kfree(params.acl); return err; } +static int nl80211_get_beacon(struct sk_buff *skb, struct genl_info *info) +{ + struct net_device *dev = info->user_ptr[1]; + struct wireless_dev *wdev = dev->ieee80211_ptr; + struct sk_buff *msg; + + if (wdev->iftype != NL80211_IFTYPE_AP && + wdev->iftype != NL80211_IFTYPE_P2P_GO) + return -EOPNOTSUPP; + + if (!wdev->beacon_interval) + return -EINVAL; + + msg = nlmsg_new(nl80211_beacon_size(&wdev->beacon), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + if (nl80211_send_beacon(msg, NL80211_CMD_GET_BEACON, info->snd_portid, + info->snd_seq, 0, &wdev->beacon) < 0) { + nlmsg_free(msg); + return -ENOBUFS; + } + + return genlmsg_reply(msg, info); +} + static int nl80211_set_beacon(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 cfg80211_beacon_data params; + struct cfg80211_beacon_data merged_bcn; int err; if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP && @@ -4108,10 +4311,19 @@ static int nl80211_set_beacon(struct sk_buff *skb, struct genl_info *info) if (err) return err; + err = nl80211_merge_beacons(&merged_bcn, &wdev->beacon, ¶ms); + if (err) + return err; + wdev_lock(wdev); err = rdev_change_beacon(rdev, dev, ¶ms); + if (!err) + nl80211_assign_beacon(&wdev->beacon, &merged_bcn); wdev_unlock(wdev); + if (err) + nl80211_free_beacon(&merged_bcn); + return err; } @@ -12595,6 +12807,14 @@ static const struct genl_ops nl80211_ops[] = { NL80211_FLAG_NEED_RTNL, }, { + .cmd = NL80211_CMD_GET_BEACON, + .policy = nl80211_policy, + .flags = GENL_UNS_ADMIN_PERM, + .doit = nl80211_get_beacon, + .internal_flags = NL80211_FLAG_NEED_NETDEV_UP | + NL80211_FLAG_NEED_RTNL, + }, + { .cmd = NL80211_CMD_SET_BEACON, .policy = nl80211_policy, .flags = GENL_UNS_ADMIN_PERM, -- 2.11.0