From: Sara Sharon <sara.sharon@xxxxxxxxx>
Since an element is limited to 255 octets, a profile may be split
split to several elements. Support the split as defined in the 11ax
draft 3. Detect legacy split and print a net-rate limited warning,
since there is no ROI in supporting this probably non-existent
split.
Signed-off-by: Sara Sharon <sara.sharon@xxxxxxxxx>
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
---
include/net/cfg80211.h | 14 ++++++
net/wireless/scan.c | 109 ++++++++++++++++++++++++++++++++++++++---
2 files changed, 117 insertions(+), 6 deletions(-)
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index cd47b7085f59..f192c65fe9b4 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5499,6 +5499,20 @@ static inline void cfg80211_gen_new_bssid(const u8 *bssid, u8 max_bssid,
bool cfg80211_is_element_inherited(const struct element *element,
const struct element *non_inherit_element);
+/**
+ * cfg80211_merge_profile - merges a MBSSID profile if it is split between IEs
+ * @ie: ies
+ * @ielen: length of IEs
+ * @mbssid_elem: current MBSSID element
+ * @sub_elem: current MBSSID subelement (profile)
+ * @merged_ie: location of the merged profile
+ * @max_copy_len: max merged profile length
+ */
+size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
+ const struct element *mbssid_elem,
+ const struct element *sub_elem,
+ u8 **merged_ie, size_t max_copy_len);
+
/**
* enum cfg80211_bss_frame_type - frame type that the BSS data came from
* @CFG80211_BSS_FTYPE_UNKNOWN: driver doesn't know whether the data is
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index bda9114ded77..878c867f3f7d 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -1456,6 +1456,78 @@ cfg80211_inform_single_bss_data(struct wiphy *wiphy,
return &res->pub;
}
+static const struct element
+*cfg80211_get_profile_continuation(const u8 *ie, size_t ielen,
+ const struct element *mbssid_elem,
+ const struct element *sub_elem)
+{
+ const u8 *mbssid_end = mbssid_elem->data + mbssid_elem->datalen;
+ const struct element *next_mbssid;
+ const struct element *next_sub;
+
+ next_mbssid = cfg80211_find_elem(WLAN_EID_MULTIPLE_BSSID,
+ mbssid_end,
+ ielen - (mbssid_end - ie));
+
+ /*
+ * If is is not the last subelement in current MBSSID IE or there isn't
+ * a next MBSSID IE - profile is complete.
+ */
+ if ((sub_elem->data + sub_elem->datalen < mbssid_end - 1) ||
+ !next_mbssid)
+ return NULL;
+
+ /* For any length error, just return NULL */
+
+ if (next_mbssid->datalen < 4)
+ return NULL;
+
+ next_sub = (void *)&next_mbssid->data[1];
+
+ if (next_mbssid->data + next_mbssid->datalen <
+ next_sub->data + next_sub->datalen)
+ return NULL;
+
+ if (next_sub->id != 0 || next_sub->datalen < 2)
+ return NULL;
+
+ /*
+ * Check if the first element in the next sub element is a start
+ * of a new profile
+ */
+ return next_sub->data[0] == WLAN_EID_NON_TX_BSSID_CAP ?
+ NULL : next_mbssid;
+}
+
+size_t cfg80211_merge_profile(const u8 *ie, size_t ielen,
+ const struct element *mbssid_elem,
+ const struct element *sub_elem,
+ u8 **merged_ie, size_t max_copy_len)
+{
+ size_t copied_len = sub_elem->datalen;
+ const struct element *next_mbssid;
+
+ if (sub_elem->datalen > max_copy_len)
+ return 0;
+
+ memcpy(*merged_ie, sub_elem->data, sub_elem->datalen);
+
+ while ((next_mbssid = cfg80211_get_profile_continuation(ie, ielen,
+ mbssid_elem,
+ sub_elem))) {
+ const struct element *next_sub = (void *)&next_mbssid->data[1];
+
+ if (copied_len + next_sub->datalen > max_copy_len)
+ break;
+ memcpy(*merged_ie + copied_len, next_sub->data,
+ next_sub->datalen);
+ copied_len += next_sub->datalen;
+ }
+
+ return copied_len;
+}
+EXPORT_SYMBOL(cfg80211_merge_profile);
+
static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
struct cfg80211_inform_bss *data,
enum cfg80211_bss_frame_type ftype,
@@ -1469,7 +1541,8 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
const struct element *elem, *sub;
size_t new_ie_len;
u8 new_bssid[ETH_ALEN];
- u8 *new_ie;
+ u8 *new_ie, *profile;
+ u64 seen_indices = 0;
u16 capability;
struct cfg80211_bss *bss;
@@ -1487,10 +1560,16 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
if (!new_ie)
return;
+ profile = kmalloc(ielen, gfp);
+ if (!profile)
+ goto out;
+
for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) {
if (elem->datalen < 4)
continue;
for_each_element(sub, elem->data + 1, elem->datalen - 1) {
+ u8 profile_len;
+
if (sub->id != 0 || sub->datalen < 4) {
/* not a valid BSS profile */
continue;
@@ -1505,16 +1584,31 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
continue;
}
+ memset(profile, 0, ielen);
+ profile_len = cfg80211_merge_profile(ie, ielen,
+ elem,
+ sub,
+ &profile,
+ ielen);
+
/* found a Nontransmitted BSSID Profile */
mbssid_index_ie = cfg80211_find_ie
(WLAN_EID_MULTI_BSSID_IDX,
- sub->data, sub->datalen);
+ profile, profile_len);
if (!mbssid_index_ie || mbssid_index_ie[1] < 1 ||
- mbssid_index_ie[2] == 0) {
+ mbssid_index_ie[2] == 0 ||
+ mbssid_index_ie[2] > 46) {
/* No valid Multiple BSSID-Index element */
continue;
}
+ if (seen_indices & BIT(mbssid_index_ie[2]))
+ /* We don't support legacy split of a profile */
+ net_dbg_ratelimited("Partial info for BSSID index %d\n",
+ mbssid_index_ie[2]);
+
+ seen_indices |= BIT(mbssid_index_ie[2]);
+
non_tx_data->bssid_index = mbssid_index_ie[2];
non_tx_data->max_bssid_indicator = elem->data[0];
@@ -1523,13 +1617,14 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
non_tx_data->bssid_index,
new_bssid);
memset(new_ie, 0, IEEE80211_MAX_DATA_LEN);
- new_ie_len = cfg80211_gen_new_ie(ie, ielen, sub->data,
- sub->datalen, new_ie,
+ new_ie_len = cfg80211_gen_new_ie(ie, ielen,
+ profile,
+ profile_len, new_ie,
gfp);
if (!new_ie_len)
continue;
- capability = get_unaligned_le16(sub->data + 2);
+ capability = get_unaligned_le16(profile + 2);
bss = cfg80211_inform_single_bss_data(wiphy, data,
ftype,
new_bssid, tsf,
@@ -1545,7 +1640,9 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy,
}
}
+out:
kfree(new_ie);
+ kfree(profile);
}
struct cfg80211_bss *
--
2.20.1
