From fd17bf041b40e3dac705c4313854becbe07b7557 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Tue, 28 Jun 2022 17:49:12 +0200 Subject: [PATCH] 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 --- net/mac80211/ieee80211_i.h | 50 ++++++++++++++++++++++++++++---- net/mac80211/util.c | 58 +++++++++++++++++++------------------- 2 files changed, 74 insertions(+), 34 deletions(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index a0743c78d171..2cf13ea4c9f7 100644 --- 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(¶ms); +} + 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 2b2c8e1472f3..0ff09c639c50 100644 --- 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; }