wifi: mac80211: refactor elements parsing with parameter struct

Refactor the element parsing into a version that has
a parameter struct so we can add more parameters more
easily in the future.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index a0743c78d171f34e4a4dcd31986ff41cfe55c23a..2cf13ea4c9f74b20bde29574068a8812ced575e4 100644 (file)
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -2138,11 +2138,51 @@ static inline void ieee80211_tx_skb(struct ieee80211_sub_if_data *sdata,
        ieee80211_tx_skb_tid(sdata, skb, 7);
 }
 
-struct ieee802_11_elems *ieee802_11_parse_elems_crc(const u8 *start, size_t len,
-                                                   bool action,
-                                                   u64 filter, u32 crc,
-                                                   const u8 *transmitter_bssid,
-                                                   const u8 *bss_bssid);
+/**
+ * struct ieee80211_elems_parse_params - element parsing parameters
+ * @start: pointer to the elements
+ * @len: length of the elements
+ * @action: %true if the elements came from an action frame
+ * @filter: bitmap of element IDs to filter out while calculating
+ *     the element CRC
+ * @crc: CRC starting value
+ * @transmitter_bssid: transmitter BSSID to parse the multi-BSSID
+ *     element
+ * @bss_bssid: BSSID of the BSS we want to obtain elements for
+ *     when parsing the multi-BSSID element
+ */
+struct ieee80211_elems_parse_params {
+       const u8 *start;
+       size_t len;
+       bool action;
+       u64 filter;
+       u32 crc;
+       const u8 *transmitter_bssid;
+       const u8 *bss_bssid;
+};
+
+struct ieee802_11_elems *
+ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params);
+
+static inline struct ieee802_11_elems *
+ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action,
+                          u64 filter, u32 crc,
+                          const u8 *transmitter_bssid,
+                          const u8 *bss_bssid)
+{
+       struct ieee80211_elems_parse_params params = {
+               .start = start,
+               .len = len,
+               .action = action,
+               .filter = filter,
+               .crc = crc,
+               .transmitter_bssid = transmitter_bssid,
+               .bss_bssid = bss_bssid,
+       };
+
+       return ieee802_11_parse_elems_full(&params);
+}
+
 static inline struct ieee802_11_elems *
 ieee802_11_parse_elems(const u8 *start, size_t len, bool action,
                       const u8 *transmitter_bssid,

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 2b2c8e1472f3c5600bde4207e5845031a3afea94..0ff09c639c50c1cd13db580ed833a6a67e6dc50e 100644 (file)
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1026,19 +1026,19 @@ static void ieee80211_parse_extension_element(u32 *crc,
 }
 
 static u32
-_ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action,
-                           struct ieee802_11_elems *elems,
-                           u64 filter, u32 crc,
-                           const struct element *check_inherit)
+_ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params,
+                            struct ieee802_11_elems *elems,
+                            const struct element *check_inherit)
 {
        const struct element *elem;
-       bool calc_crc = filter != 0;
+       bool calc_crc = params->filter != 0;
        DECLARE_BITMAP(seen_elems, 256);
+       u32 crc = params->crc;
        const u8 *ie;
 
        bitmap_zero(seen_elems, 256);
 
-       for_each_element(elem, start, len) {
+       for_each_element(elem, params->start, params->len) {
                bool elem_parse_failed;
                u8 id = elem->id;
                u8 elen = elem->datalen;
@@ -1101,7 +1101,7 @@ _ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action,
                        break;
                }
 
-               if (calc_crc && id < 64 && (filter & (1ULL << id)))
+               if (calc_crc && id < 64 && (params->filter & (1ULL << id)))
                        crc = crc32_be(crc, pos - 2, elen + 2);
 
                elem_parse_failed = false;
@@ -1282,7 +1282,7 @@ _ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action,
                        elems->mesh_chansw_params_ie = (void *)pos;
                        break;
                case WLAN_EID_WIDE_BW_CHANNEL_SWITCH:
-                       if (!action ||
+                       if (!params->action ||
                            elen < sizeof(*elems->wide_bw_chansw_ie)) {
                                elem_parse_failed = true;
                                break;
@@ -1290,7 +1290,7 @@ _ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action,
                        elems->wide_bw_chansw_ie = (void *)pos;
                        break;
                case WLAN_EID_CHANNEL_SWITCH_WRAPPER:
-                       if (action) {
+                       if (params->action) {
                                elem_parse_failed = true;
                                break;
                        }
@@ -1417,7 +1417,7 @@ _ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action,
                        __set_bit(id, seen_elems);
        }
 
-       if (!for_each_element_completed(elem, start, len))
+       if (!for_each_element_completed(elem, params->start, params->len))
                elems->parse_error = true;
 
        return crc;
@@ -1491,11 +1491,8 @@ static size_t ieee802_11_find_bssid_profile(const u8 *start, size_t len,
        return found ? profile_len : 0;
 }
 
-struct ieee802_11_elems *ieee802_11_parse_elems_crc(const u8 *start, size_t len,
-                                                   bool action, u64 filter,
-                                                   u32 crc,
-                                                   const u8 *transmitter_bssid,
-                                                   const u8 *bss_bssid)
+struct ieee802_11_elems *
+ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params)
 {
        struct ieee802_11_elems *elems;
        const struct element *non_inherit = NULL;
@@ -1505,15 +1502,16 @@ struct ieee802_11_elems *ieee802_11_parse_elems_crc(const u8 *start, size_t len,
        elems = kzalloc(sizeof(*elems), GFP_ATOMIC);
        if (!elems)
                return NULL;
-       elems->ie_start = start;
-       elems->total_len = len;
+       elems->ie_start = params->start;
+       elems->total_len = params->len;
 
-       nontransmitted_profile = kmalloc(len, GFP_ATOMIC);
+       nontransmitted_profile = kmalloc(params->len, GFP_ATOMIC);
        if (nontransmitted_profile) {
                nontransmitted_profile_len =
-                       ieee802_11_find_bssid_profile(start, len, elems,
-                                                     transmitter_bssid,
-                                                     bss_bssid,
+                       ieee802_11_find_bssid_profile(params->start, params->len,
+                                                     elems,
+                                                     params->transmitter_bssid,
+                                                     params->bss_bssid,
                                                      nontransmitted_profile);
                non_inherit =
                        cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE,
@@ -1521,14 +1519,18 @@ struct ieee802_11_elems *ieee802_11_parse_elems_crc(const u8 *start, size_t len,
                                               nontransmitted_profile_len);
        }
 
-       crc = _ieee802_11_parse_elems_crc(start, len, action, elems, filter,
-                                         crc, non_inherit);
+       elems->crc = _ieee802_11_parse_elems_full(params, elems, non_inherit);
 
        /* Override with nontransmitted profile, if found */
-       if (nontransmitted_profile_len)
-               _ieee802_11_parse_elems_crc(nontransmitted_profile,
-                                           nontransmitted_profile_len,
-                                           action, elems, 0, 0, NULL);
+       if (nontransmitted_profile_len) {
+               struct ieee80211_elems_parse_params sub = {
+                       .start = nontransmitted_profile,
+                       .len = nontransmitted_profile_len,
+                       .action = params->action,
+               };
+
+               _ieee802_11_parse_elems_full(&sub, elems, NULL);
+       }
 
        if (elems->tim && !elems->parse_error) {
                const struct ieee80211_tim_ie *tim_ie = elems->tim;
@@ -1550,8 +1552,6 @@ struct ieee802_11_elems *ieee802_11_parse_elems_crc(const u8 *start, size_t len,
 
        kfree(nontransmitted_profile);
 
-       elems->crc = crc;
-
        return elems;
 }