wifi: ieee80211: add helper to validate ML element type and size

[carl9170fw.git] / include / linux / ieee80211.h

diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index 01f42291a7ab65587bb53e135c4a2a8623d1e0e3..f6c9e2b46b11e896b3d0a5859edefa50f555f490 100644 (file)
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h
@@ -4567,10 +4567,10 @@ static inline u8 ieee80211_mle_common_size(const u8 *data)
  * ieee80211_mle_get_eml_sync_delay - returns the medium sync delay
  * @data: pointer to the multi link EHT IE
  *
- * The element is assumed to be big enough. This must be checked by
- * ieee80211_mle_size_ok().
- * If the medium synchronization can't be found (the type is not basic, or
- * the medium sync presence bit is clear), 0 will be returned.
+ * The element is assumed to be of the correct type (BASIC) and big enough,
+ * this must be checked using ieee80211_mle_type_ok().
+ *
+ * If the medium synchronization is not present, then 0 is returned.
  */
 static inline u16 ieee80211_mle_get_eml_med_sync_delay(const u8 *data)
 {
@@ -4578,13 +4578,7 @@ static inline u16 ieee80211_mle_get_eml_med_sync_delay(const u8 *data)
        u16 control = le16_to_cpu(mle->control);
        const u8 *common = mle->variable;
 
-       if (u16_get_bits(control, IEEE80211_ML_CONTROL_TYPE) !=
-           IEEE80211_ML_CONTROL_TYPE_BASIC)
-               return 0;
-
-       /* common points now at the beginning of
-        * ieee80211_mle_basic_common_info
-        */
+       /* common points now at the beginning of ieee80211_mle_basic_common_info */
        common += sizeof(struct ieee80211_mle_basic_common_info);
 
        if (!(control & IEEE80211_MLC_BASIC_PRES_MED_SYNC_DELAY))
@@ -4602,10 +4596,10 @@ static inline u16 ieee80211_mle_get_eml_med_sync_delay(const u8 *data)
  * ieee80211_mle_get_eml_cap - returns the EML capability
  * @data: pointer to the multi link EHT IE
  *
- * The element is assumed to be big enough. This must be checked by
- * ieee80211_mle_size_ok().
- * If the EML capability can't be found (the type is not basic, or
- * the EML capability presence bit is clear), 0 will be returned.
+ * The element is assumed to be of the correct type (BASIC) and big enough,
+ * this must be checked using ieee80211_mle_type_ok().
+ *
+ * If the EML capability is not present, 0 will be returned.
  */
 static inline u16 ieee80211_mle_get_eml_cap(const u8 *data)
 {
@@ -4613,10 +4607,6 @@ static inline u16 ieee80211_mle_get_eml_cap(const u8 *data)
        u16 control = le16_to_cpu(mle->control);
        const u8 *common = mle->variable;
 
-       if (u16_get_bits(control, IEEE80211_ML_CONTROL_TYPE) !=
-           IEEE80211_ML_CONTROL_TYPE_BASIC)
-               return 0;
-
        /* common points now at the beginning of ieee80211_mle_basic_common_info */
        common += sizeof(struct ieee80211_mle_basic_common_info);
 
@@ -4701,6 +4691,28 @@ static inline bool ieee80211_mle_size_ok(const u8 *data, size_t len)
        return mle->variable[0] >= common;
 }
 
+/**
+ * ieee80211_mle_type_ok - validate multi-link element type and size
+ * @data: pointer to the element data
+ * @type: expected type of the element
+ * @len: length of the containing element
+ */
+static inline bool ieee80211_mle_type_ok(const u8 *data, u8 type, size_t len)
+{
+       const struct ieee80211_multi_link_elem *mle = (const void *)data;
+       u16 control;
+
+       if (!ieee80211_mle_size_ok(data, len))
+               return false;
+
+       control = le16_to_cpu(mle->control);
+
+       if (u16_get_bits(control, IEEE80211_ML_CONTROL_TYPE) == type)
+               return true;
+
+       return false;
+}
+
 enum ieee80211_mle_subelems {
        IEEE80211_MLE_SUBELEM_PER_STA_PROFILE           = 0,
        IEEE80211_MLE_SUBELEM_FRAGMENT                  = 254,