From d4e50c5917e110451ced8f8de594cea858791f37 Mon Sep 17 00:00:00 2001 From: Michal Kazior Date: Fri, 29 Jun 2012 12:47:07 +0200 Subject: [PATCH] cfg80211: add channel checking for iface combinations .connect cannot be handled since the driver scans and connects on its own. It is up to the driver then to refuse a connection (with -EBUSY for example). Non-fixed channel IBSSes always take a single channel resource. For example two non-fixed channel IBSSes always take up 2 num_different_channels, even if they operate on the same channel at a given point of time. Signed-off-by: Michal Kazior Signed-off-by: Johannes Berg --- net/wireless/core.c | 8 ++++++ net/wireless/core.h | 29 +++++++++++++++++++--- net/wireless/util.c | 59 +++++++++++++++++++++++++++++++++++++++++---- 3 files changed, 88 insertions(+), 8 deletions(-) diff --git a/net/wireless/core.c b/net/wireless/core.c index 580551e9caba..b26695ad3e97 100644 --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -373,6 +373,14 @@ static int wiphy_verify_combinations(struct wiphy *wiphy) if (WARN_ON(!c->num_different_channels)) return -EINVAL; + /* + * Put a sane limit on maximum number of different + * channels to simplify channel accounting code. + */ + if (WARN_ON(c->num_different_channels > + CFG80211_MAX_NUM_DIFFERENT_CHANNELS)) + return -EINVAL; + if (WARN_ON(!c->n_limits)) return -EINVAL; diff --git a/net/wireless/core.h b/net/wireless/core.h index d5efe1b0a8f7..81fef3ddb5a8 100644 --- a/net/wireless/core.h +++ b/net/wireless/core.h @@ -428,9 +428,20 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev, u32 *flags, struct vif_params *params); void cfg80211_process_rdev_events(struct cfg80211_registered_device *rdev); -int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, - struct wireless_dev *wdev, - enum nl80211_iftype iftype); +int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev, + struct wireless_dev *wdev, + enum nl80211_iftype iftype, + struct ieee80211_channel *chan, + enum cfg80211_chan_mode chanmode); + +static inline int +cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, + struct wireless_dev *wdev, + enum nl80211_iftype iftype) +{ + return cfg80211_can_use_iftype_chan(rdev, wdev, iftype, NULL, + CHAN_MODE_UNDEFINED); +} static inline int cfg80211_can_add_interface(struct cfg80211_registered_device *rdev, @@ -439,6 +450,16 @@ cfg80211_can_add_interface(struct cfg80211_registered_device *rdev, return cfg80211_can_change_interface(rdev, NULL, iftype); } +static inline int +cfg80211_can_use_chan(struct cfg80211_registered_device *rdev, + struct wireless_dev *wdev, + struct ieee80211_channel *chan, + enum cfg80211_chan_mode chanmode) +{ + return cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype, + chan, chanmode); +} + void cfg80211_get_chan_state(struct cfg80211_registered_device *rdev, struct wireless_dev *wdev, @@ -461,6 +482,8 @@ int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev, void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev, enum nl80211_iftype iftype, int num); +#define CFG80211_MAX_NUM_DIFFERENT_CHANNELS 10 + #ifdef CONFIG_CFG80211_DEVELOPER_WARNINGS #define CFG80211_DEV_WARN_ON(cond) WARN_ON(cond) #else diff --git a/net/wireless/util.c b/net/wireless/util.c index 9b92ec57d07b..4713cea9a2fa 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -938,13 +938,20 @@ int cfg80211_validate_beacon_int(struct cfg80211_registered_device *rdev, return res; } -int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, - struct wireless_dev *wdev, - enum nl80211_iftype iftype) +int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev, + struct wireless_dev *wdev, + enum nl80211_iftype iftype, + struct ieee80211_channel *chan, + enum cfg80211_chan_mode chanmode) { struct wireless_dev *wdev_iter; u32 used_iftypes = BIT(iftype); int num[NUM_NL80211_IFTYPES]; + struct ieee80211_channel + *used_channels[CFG80211_MAX_NUM_DIFFERENT_CHANNELS]; + struct ieee80211_channel *ch; + enum cfg80211_chan_mode chmode; + int num_different_channels = 0; int total = 1; int i, j; @@ -955,9 +962,23 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, return 0; memset(num, 0, sizeof(num)); + memset(used_channels, 0, sizeof(used_channels)); num[iftype] = 1; + switch (chanmode) { + case CHAN_MODE_UNDEFINED: + break; + case CHAN_MODE_SHARED: + WARN_ON(!chan); + used_channels[0] = chan; + num_different_channels++; + break; + case CHAN_MODE_EXCLUSIVE: + num_different_channels++; + break; + } + mutex_lock(&rdev->devlist_mtx); list_for_each_entry(wdev_iter, &rdev->netdev_list, list) { if (wdev_iter == wdev) @@ -968,6 +989,31 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, if (rdev->wiphy.software_iftypes & BIT(wdev_iter->iftype)) continue; + cfg80211_get_chan_state(rdev, wdev_iter, &ch, &chmode); + + switch (chmode) { + case CHAN_MODE_UNDEFINED: + break; + case CHAN_MODE_SHARED: + for (i = 0; i < CFG80211_MAX_NUM_DIFFERENT_CHANNELS; i++) + if (!used_channels[i] || used_channels[i] == ch) + break; + + if (i == CFG80211_MAX_NUM_DIFFERENT_CHANNELS) { + mutex_unlock(&rdev->devlist_mtx); + return -EBUSY; + } + + if (used_channels[i] == NULL) { + used_channels[i] = ch; + num_different_channels++; + } + break; + case CHAN_MODE_EXCLUSIVE: + num_different_channels++; + break; + } + num[wdev_iter->iftype]++; total++; used_iftypes |= BIT(wdev_iter->iftype); @@ -984,12 +1030,15 @@ int cfg80211_can_change_interface(struct cfg80211_registered_device *rdev, c = &rdev->wiphy.iface_combinations[i]; + if (total > c->max_interfaces) + continue; + if (num_different_channels > c->num_different_channels) + continue; + limits = kmemdup(c->limits, sizeof(limits[0]) * c->n_limits, GFP_KERNEL); if (!limits) return -ENOMEM; - if (total > c->max_interfaces) - goto cont; for (iftype = 0; iftype < NUM_NL80211_IFTYPES; iftype++) { if (rdev->wiphy.software_iftypes & BIT(iftype)) -- GitLab