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-rw-r--r--net/wireless/reg.c480
1 files changed, 446 insertions, 34 deletions
diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 87ea60d84c3..ed89c59bb43 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -43,6 +43,15 @@
#include "regdb.h"
#include "nl80211.h"
+#ifdef CONFIG_CFG80211_REG_DEBUG
+#define REG_DBG_PRINT(format, args...) \
+ do { \
+ printk(KERN_DEBUG format , ## args); \
+ } while (0)
+#else
+#define REG_DBG_PRINT(args...)
+#endif
+
/* Receipt of information from last regulatory request */
static struct regulatory_request *last_request;
@@ -125,6 +134,7 @@ static const struct ieee80211_regdomain *cfg80211_world_regdom =
&world_regdom;
static char *ieee80211_regdom = "00";
+static char user_alpha2[2];
module_param(ieee80211_regdom, charp, 0444);
MODULE_PARM_DESC(ieee80211_regdom, "IEEE 802.11 regulatory domain code");
@@ -243,6 +253,27 @@ static bool regdom_changes(const char *alpha2)
return true;
}
+/*
+ * The NL80211_REGDOM_SET_BY_USER regdom alpha2 is cached, this lets
+ * you know if a valid regulatory hint with NL80211_REGDOM_SET_BY_USER
+ * has ever been issued.
+ */
+static bool is_user_regdom_saved(void)
+{
+ if (user_alpha2[0] == '9' && user_alpha2[1] == '7')
+ return false;
+
+ /* This would indicate a mistake on the design */
+ if (WARN((!is_world_regdom(user_alpha2) &&
+ !is_an_alpha2(user_alpha2)),
+ "Unexpected user alpha2: %c%c\n",
+ user_alpha2[0],
+ user_alpha2[1]))
+ return false;
+
+ return true;
+}
+
/**
* country_ie_integrity_changes - tells us if the country IE has changed
* @checksum: checksum of country IE of fields we are interested in
@@ -476,12 +507,212 @@ static bool freq_in_rule_band(const struct ieee80211_freq_range *freq_range,
}
/*
+ * This is a work around for sanity checking ieee80211_channel_to_frequency()'s
+ * work. ieee80211_channel_to_frequency() can for example currently provide a
+ * 2 GHz channel when in fact a 5 GHz channel was desired. An example would be
+ * an AP providing channel 8 on a country IE triplet when it sent this on the
+ * 5 GHz band, that channel is designed to be channel 8 on 5 GHz, not a 2 GHz
+ * channel.
+ *
+ * This can be removed once ieee80211_channel_to_frequency() takes in a band.
+ */
+static bool chan_in_band(int chan, enum ieee80211_band band)
+{
+ int center_freq = ieee80211_channel_to_frequency(chan);
+
+ switch (band) {
+ case IEEE80211_BAND_2GHZ:
+ if (center_freq <= 2484)
+ return true;
+ return false;
+ case IEEE80211_BAND_5GHZ:
+ if (center_freq >= 5005)
+ return true;
+ return false;
+ default:
+ return false;
+ }
+}
+
+/*
+ * Some APs may send a country IE triplet for each channel they
+ * support and while this is completely overkill and silly we still
+ * need to support it. We avoid making a single rule for each channel
+ * though and to help us with this we use this helper to find the
+ * actual subband end channel. These type of country IE triplet
+ * scenerios are handled then, all yielding two regulaotry rules from
+ * parsing a country IE:
+ *
+ * [1]
+ * [2]
+ * [36]
+ * [40]
+ *
+ * [1]
+ * [2-4]
+ * [5-12]
+ * [36]
+ * [40-44]
+ *
+ * [1-4]
+ * [5-7]
+ * [36-44]
+ * [48-64]
+ *
+ * [36-36]
+ * [40-40]
+ * [44-44]
+ * [48-48]
+ * [52-52]
+ * [56-56]
+ * [60-60]
+ * [64-64]
+ * [100-100]
+ * [104-104]
+ * [108-108]
+ * [112-112]
+ * [116-116]
+ * [120-120]
+ * [124-124]
+ * [128-128]
+ * [132-132]
+ * [136-136]
+ * [140-140]
+ *
+ * Returns 0 if the IE has been found to be invalid in the middle
+ * somewhere.
+ */
+static int max_subband_chan(enum ieee80211_band band,
+ int orig_cur_chan,
+ int orig_end_channel,
+ s8 orig_max_power,
+ u8 **country_ie,
+ u8 *country_ie_len)
+{
+ u8 *triplets_start = *country_ie;
+ u8 len_at_triplet = *country_ie_len;
+ int end_subband_chan = orig_end_channel;
+
+ /*
+ * We'll deal with padding for the caller unless
+ * its not immediate and we don't process any channels
+ */
+ if (*country_ie_len == 1) {
+ *country_ie += 1;
+ *country_ie_len -= 1;
+ return orig_end_channel;
+ }
+
+ /* Move to the next triplet and then start search */
+ *country_ie += 3;
+ *country_ie_len -= 3;
+
+ if (!chan_in_band(orig_cur_chan, band))
+ return 0;
+
+ while (*country_ie_len >= 3) {
+ int end_channel = 0;
+ struct ieee80211_country_ie_triplet *triplet =
+ (struct ieee80211_country_ie_triplet *) *country_ie;
+ int cur_channel = 0, next_expected_chan;
+
+ /* means last triplet is completely unrelated to this one */
+ if (triplet->ext.reg_extension_id >=
+ IEEE80211_COUNTRY_EXTENSION_ID) {
+ *country_ie -= 3;
+ *country_ie_len += 3;
+ break;
+ }
+
+ if (triplet->chans.first_channel == 0) {
+ *country_ie += 1;
+ *country_ie_len -= 1;
+ if (*country_ie_len != 0)
+ return 0;
+ break;
+ }
+
+ if (triplet->chans.num_channels == 0)
+ return 0;
+
+ /* Monitonically increasing channel order */
+ if (triplet->chans.first_channel <= end_subband_chan)
+ return 0;
+
+ if (!chan_in_band(triplet->chans.first_channel, band))
+ return 0;
+
+ /* 2 GHz */
+ if (triplet->chans.first_channel <= 14) {
+ end_channel = triplet->chans.first_channel +
+ triplet->chans.num_channels - 1;
+ }
+ else {
+ end_channel = triplet->chans.first_channel +
+ (4 * (triplet->chans.num_channels - 1));
+ }
+
+ if (!chan_in_band(end_channel, band))
+ return 0;
+
+ if (orig_max_power != triplet->chans.max_power) {
+ *country_ie -= 3;
+ *country_ie_len += 3;
+ break;
+ }
+
+ cur_channel = triplet->chans.first_channel;
+
+ /* The key is finding the right next expected channel */
+ if (band == IEEE80211_BAND_2GHZ)
+ next_expected_chan = end_subband_chan + 1;
+ else
+ next_expected_chan = end_subband_chan + 4;
+
+ if (cur_channel != next_expected_chan) {
+ *country_ie -= 3;
+ *country_ie_len += 3;
+ break;
+ }
+
+ end_subband_chan = end_channel;
+
+ /* Move to the next one */
+ *country_ie += 3;
+ *country_ie_len -= 3;
+
+ /*
+ * Padding needs to be dealt with if we processed
+ * some channels.
+ */
+ if (*country_ie_len == 1) {
+ *country_ie += 1;
+ *country_ie_len -= 1;
+ break;
+ }
+
+ /* If seen, the IE is invalid */
+ if (*country_ie_len == 2)
+ return 0;
+ }
+
+ if (end_subband_chan == orig_end_channel) {
+ *country_ie = triplets_start;
+ *country_ie_len = len_at_triplet;
+ return orig_end_channel;
+ }
+
+ return end_subband_chan;
+}
+
+/*
* Converts a country IE to a regulatory domain. A regulatory domain
* structure has a lot of information which the IE doesn't yet have,
* so for the other values we use upper max values as we will intersect
* with our userspace regulatory agent to get lower bounds.
*/
static struct ieee80211_regdomain *country_ie_2_rd(
+ enum ieee80211_band band,
u8 *country_ie,
u8 country_ie_len,
u32 *checksum)
@@ -543,10 +774,29 @@ static struct ieee80211_regdomain *country_ie_2_rd(
continue;
}
+ /*
+ * APs can add padding to make length divisible
+ * by two, required by the spec.
+ */
+ if (triplet->chans.first_channel == 0) {
+ country_ie++;
+ country_ie_len--;
+ /* This is expected to be at the very end only */
+ if (country_ie_len != 0)
+ return NULL;
+ break;
+ }
+
+ if (triplet->chans.num_channels == 0)
+ return NULL;
+
+ if (!chan_in_band(triplet->chans.first_channel, band))
+ return NULL;
+
/* 2 GHz */
- if (triplet->chans.first_channel <= 14)
+ if (band == IEEE80211_BAND_2GHZ)
end_channel = triplet->chans.first_channel +
- triplet->chans.num_channels;
+ triplet->chans.num_channels - 1;
else
/*
* 5 GHz -- For example in country IEs if the first
@@ -561,6 +811,24 @@ static struct ieee80211_regdomain *country_ie_2_rd(
(4 * (triplet->chans.num_channels - 1));
cur_channel = triplet->chans.first_channel;
+
+ /*
+ * Enhancement for APs that send a triplet for every channel
+ * or for whatever reason sends triplets with multiple channels
+ * separated when in fact they should be together.
+ */
+ end_channel = max_subband_chan(band,
+ cur_channel,
+ end_channel,
+ triplet->chans.max_power,
+ &country_ie,
+ &country_ie_len);
+ if (!end_channel)
+ return NULL;
+
+ if (!chan_in_band(end_channel, band))
+ return NULL;
+
cur_sub_max_channel = end_channel;
/* Basic sanity check */
@@ -591,10 +859,13 @@ static struct ieee80211_regdomain *country_ie_2_rd(
last_sub_max_channel = cur_sub_max_channel;
- country_ie += 3;
- country_ie_len -= 3;
num_rules++;
+ if (country_ie_len >= 3) {
+ country_ie += 3;
+ country_ie_len -= 3;
+ }
+
/*
* Note: this is not a IEEE requirement but
* simply a memory requirement
@@ -637,6 +908,12 @@ static struct ieee80211_regdomain *country_ie_2_rd(
continue;
}
+ if (triplet->chans.first_channel == 0) {
+ country_ie++;
+ country_ie_len--;
+ break;
+ }
+
reg_rule = &rd->reg_rules[i];
freq_range = &reg_rule->freq_range;
power_rule = &reg_rule->power_rule;
@@ -644,13 +921,20 @@ static struct ieee80211_regdomain *country_ie_2_rd(
reg_rule->flags = flags;
/* 2 GHz */
- if (triplet->chans.first_channel <= 14)
+ if (band == IEEE80211_BAND_2GHZ)
end_channel = triplet->chans.first_channel +
- triplet->chans.num_channels;
+ triplet->chans.num_channels -1;
else
end_channel = triplet->chans.first_channel +
(4 * (triplet->chans.num_channels - 1));
+ end_channel = max_subband_chan(band,
+ triplet->chans.first_channel,
+ end_channel,
+ triplet->chans.max_power,
+ &country_ie,
+ &country_ie_len);
+
/*
* The +10 is since the regulatory domain expects
* the actual band edge, not the center of freq for
@@ -671,12 +955,15 @@ static struct ieee80211_regdomain *country_ie_2_rd(
*/
freq_range->max_bandwidth_khz = MHZ_TO_KHZ(40);
power_rule->max_antenna_gain = DBI_TO_MBI(100);
- power_rule->max_eirp = DBM_TO_MBM(100);
+ power_rule->max_eirp = DBM_TO_MBM(triplet->chans.max_power);
- country_ie += 3;
- country_ie_len -= 3;
i++;
+ if (country_ie_len >= 3) {
+ country_ie += 3;
+ country_ie_len -= 3;
+ }
+
BUG_ON(i > NL80211_MAX_SUPP_REG_RULES);
}
@@ -972,25 +1259,21 @@ static void handle_channel(struct wiphy *wiphy, enum ieee80211_band band,
if (r == -ERANGE &&
last_request->initiator ==
NL80211_REGDOM_SET_BY_COUNTRY_IE) {
-#ifdef CONFIG_CFG80211_REG_DEBUG
- printk(KERN_DEBUG "cfg80211: Leaving channel %d MHz "
+ REG_DBG_PRINT("cfg80211: Leaving channel %d MHz "
"intact on %s - no rule found in band on "
"Country IE\n",
- chan->center_freq, wiphy_name(wiphy));
-#endif
+ chan->center_freq, wiphy_name(wiphy));
} else {
/*
* In this case we know the country IE has at least one reg rule
* for the band so we respect its band definitions
*/
-#ifdef CONFIG_CFG80211_REG_DEBUG
if (last_request->initiator ==
NL80211_REGDOM_SET_BY_COUNTRY_IE)
- printk(KERN_DEBUG "cfg80211: Disabling "
+ REG_DBG_PRINT("cfg80211: Disabling "
"channel %d MHz on %s due to "
"Country IE\n",
chan->center_freq, wiphy_name(wiphy));
-#endif
flags |= IEEE80211_CHAN_DISABLED;
chan->flags = flags;
}
@@ -1385,7 +1668,7 @@ static int ignore_request(struct wiphy *wiphy,
switch (pending_request->initiator) {
case NL80211_REGDOM_SET_BY_CORE:
- return -EINVAL;
+ return 0;
case NL80211_REGDOM_SET_BY_COUNTRY_IE:
last_wiphy = wiphy_idx_to_wiphy(last_request->wiphy_idx);
@@ -1524,6 +1807,11 @@ new_request:
pending_request = NULL;
+ if (last_request->initiator == NL80211_REGDOM_SET_BY_USER) {
+ user_alpha2[0] = last_request->alpha2[0];
+ user_alpha2[1] = last_request->alpha2[1];
+ }
+
/* When r == REG_INTERSECT we do need to call CRDA */
if (r < 0) {
/*
@@ -1643,12 +1931,16 @@ static void queue_regulatory_request(struct regulatory_request *request)
schedule_work(&reg_work);
}
-/* Core regulatory hint -- happens once during cfg80211_init() */
+/*
+ * Core regulatory hint -- happens during cfg80211_init()
+ * and when we restore regulatory settings.
+ */
static int regulatory_hint_core(const char *alpha2)
{
struct regulatory_request *request;
- BUG_ON(last_request);
+ kfree(last_request);
+ last_request = NULL;
request = kzalloc(sizeof(struct regulatory_request),
GFP_KERNEL);
@@ -1659,14 +1951,12 @@ static int regulatory_hint_core(const char *alpha2)
request->alpha2[1] = alpha2[1];
request->initiator = NL80211_REGDOM_SET_BY_CORE;
- queue_regulatory_request(request);
-
/*
* This ensures last_request is populated once modules
* come swinging in and calling regulatory hints and
* wiphy_apply_custom_regulatory().
*/
- flush_scheduled_work();
+ reg_process_hint(request);
return 0;
}
@@ -1685,7 +1975,7 @@ int regulatory_hint_user(const char *alpha2)
request->wiphy_idx = WIPHY_IDX_STALE;
request->alpha2[0] = alpha2[0];
request->alpha2[1] = alpha2[1];
- request->initiator = NL80211_REGDOM_SET_BY_USER,
+ request->initiator = NL80211_REGDOM_SET_BY_USER;
queue_regulatory_request(request);
@@ -1753,8 +2043,9 @@ static bool reg_same_country_ie_hint(struct wiphy *wiphy,
* therefore cannot iterate over the rdev list here.
*/
void regulatory_hint_11d(struct wiphy *wiphy,
- u8 *country_ie,
- u8 country_ie_len)
+ enum ieee80211_band band,
+ u8 *country_ie,
+ u8 country_ie_len)
{
struct ieee80211_regdomain *rd = NULL;
char alpha2[2];
@@ -1800,9 +2091,11 @@ void regulatory_hint_11d(struct wiphy *wiphy,
wiphy_idx_valid(last_request->wiphy_idx)))
goto out;
- rd = country_ie_2_rd(country_ie, country_ie_len, &checksum);
- if (!rd)
+ rd = country_ie_2_rd(band, country_ie, country_ie_len, &checksum);
+ if (!rd) {
+ REG_DBG_PRINT("cfg80211: Ignoring bogus country IE\n");
goto out;
+ }
/*
* This will not happen right now but we leave it here for the
@@ -1845,6 +2138,123 @@ out:
mutex_unlock(&reg_mutex);
}
+static void restore_alpha2(char *alpha2, bool reset_user)
+{
+ /* indicates there is no alpha2 to consider for restoration */
+ alpha2[0] = '9';
+ alpha2[1] = '7';
+
+ /* The user setting has precedence over the module parameter */
+ if (is_user_regdom_saved()) {
+ /* Unless we're asked to ignore it and reset it */
+ if (reset_user) {
+ REG_DBG_PRINT("cfg80211: Restoring regulatory settings "
+ "including user preference\n");
+ user_alpha2[0] = '9';
+ user_alpha2[1] = '7';
+
+ /*
+ * If we're ignoring user settings, we still need to
+ * check the module parameter to ensure we put things
+ * back as they were for a full restore.
+ */
+ if (!is_world_regdom(ieee80211_regdom)) {
+ REG_DBG_PRINT("cfg80211: Keeping preference on "
+ "module parameter ieee80211_regdom: %c%c\n",
+ ieee80211_regdom[0],
+ ieee80211_regdom[1]);
+ alpha2[0] = ieee80211_regdom[0];
+ alpha2[1] = ieee80211_regdom[1];
+ }
+ } else {
+ REG_DBG_PRINT("cfg80211: Restoring regulatory settings "
+ "while preserving user preference for: %c%c\n",
+ user_alpha2[0],
+ user_alpha2[1]);
+ alpha2[0] = user_alpha2[0];
+ alpha2[1] = user_alpha2[1];
+ }
+ } else if (!is_world_regdom(ieee80211_regdom)) {
+ REG_DBG_PRINT("cfg80211: Keeping preference on "
+ "module parameter ieee80211_regdom: %c%c\n",
+ ieee80211_regdom[0],
+ ieee80211_regdom[1]);
+ alpha2[0] = ieee80211_regdom[0];
+ alpha2[1] = ieee80211_regdom[1];
+ } else
+ REG_DBG_PRINT("cfg80211: Restoring regulatory settings\n");
+}
+
+/*
+ * Restoring regulatory settings involves ingoring any
+ * possibly stale country IE information and user regulatory
+ * settings if so desired, this includes any beacon hints
+ * learned as we could have traveled outside to another country
+ * after disconnection. To restore regulatory settings we do
+ * exactly what we did at bootup:
+ *
+ * - send a core regulatory hint
+ * - send a user regulatory hint if applicable
+ *
+ * Device drivers that send a regulatory hint for a specific country
+ * keep their own regulatory domain on wiphy->regd so that does does
+ * not need to be remembered.
+ */
+static void restore_regulatory_settings(bool reset_user)
+{
+ char alpha2[2];
+ struct reg_beacon *reg_beacon, *btmp;
+
+ mutex_lock(&cfg80211_mutex);
+ mutex_lock(&reg_mutex);
+
+ reset_regdomains();
+ restore_alpha2(alpha2, reset_user);
+
+ /* Clear beacon hints */
+ spin_lock_bh(&reg_pending_beacons_lock);
+ if (!list_empty(&reg_pending_beacons)) {
+ list_for_each_entry_safe(reg_beacon, btmp,
+ &reg_pending_beacons, list) {
+ list_del(&reg_beacon->list);
+ kfree(reg_beacon);
+ }
+ }
+ spin_unlock_bh(&reg_pending_beacons_lock);
+
+ if (!list_empty(&reg_beacon_list)) {
+ list_for_each_entry_safe(reg_beacon, btmp,
+ &reg_beacon_list, list) {
+ list_del(&reg_beacon->list);
+ kfree(reg_beacon);
+ }
+ }
+
+ /* First restore to the basic regulatory settings */
+ cfg80211_regdomain = cfg80211_world_regdom;
+
+ mutex_unlock(&reg_mutex);
+ mutex_unlock(&cfg80211_mutex);
+
+ regulatory_hint_core(cfg80211_regdomain->alpha2);
+
+ /*
+ * This restores the ieee80211_regdom module parameter
+ * preference or the last user requested regulatory
+ * settings, user regulatory settings takes precedence.
+ */
+ if (is_an_alpha2(alpha2))
+ regulatory_hint_user(user_alpha2);
+}
+
+
+void regulatory_hint_disconnect(void)
+{
+ REG_DBG_PRINT("cfg80211: All devices are disconnected, going to "
+ "restore regulatory settings\n");
+ restore_regulatory_settings(false);
+}
+
static bool freq_is_chan_12_13_14(u16 freq)
{
if (freq == ieee80211_channel_to_frequency(12) ||
@@ -1870,13 +2280,12 @@ int regulatory_hint_found_beacon(struct wiphy *wiphy,
if (!reg_beacon)
return -ENOMEM;
-#ifdef CONFIG_CFG80211_REG_DEBUG
- printk(KERN_DEBUG "cfg80211: Found new beacon on "
- "frequency: %d MHz (Ch %d) on %s\n",
- beacon_chan->center_freq,
- ieee80211_frequency_to_channel(beacon_chan->center_freq),
- wiphy_name(wiphy));
-#endif
+ REG_DBG_PRINT("cfg80211: Found new beacon on "
+ "frequency: %d MHz (Ch %d) on %s\n",
+ beacon_chan->center_freq,
+ ieee80211_frequency_to_channel(beacon_chan->center_freq),
+ wiphy_name(wiphy));
+
memcpy(&reg_beacon->chan, beacon_chan,
sizeof(struct ieee80211_channel));
@@ -2235,6 +2644,9 @@ int regulatory_init(void)
cfg80211_regdomain = cfg80211_world_regdom;
+ user_alpha2[0] = '9';
+ user_alpha2[1] = '7';
+
/* We always try to get an update for the static regdomain */
err = regulatory_hint_core(cfg80211_regdomain->alpha2);
if (err) {
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-31 10:07:25 +0000