From e4d005b80deeb053526ca089510bf2e20473ef62 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 31 Jan 2020 13:12:40 +0200 Subject: [PATCH] mac80211: refactor extended element parsing This code was really ugly, refactor it a bit to make it more readable. While at it, use sizeof() and fix the UORA element length check bug. Signed-off-by: Johannes Berg Signed-off-by: Luca Coelho Link: https://lore.kernel.org/r/20200131111300.891737-4-luca@coelho.fi Signed-off-by: Johannes Berg --- net/mac80211/util.c | 75 +++++++++++++++++++++++++++++---------------- 1 file changed, 48 insertions(+), 27 deletions(-) diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 780df3e9092e..72039c8dbc38 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -890,6 +890,51 @@ void ieee80211_queue_delayed_work(struct ieee80211_hw *hw, } EXPORT_SYMBOL(ieee80211_queue_delayed_work); +static void ieee80211_parse_extension_element(u32 *crc, + const struct element *elem, + struct ieee802_11_elems *elems) +{ + const void *data = elem->data + 1; + u8 len = elem->datalen - 1; + + switch (elem->data[0]) { + case WLAN_EID_EXT_HE_MU_EDCA: + if (len == sizeof(*elems->mu_edca_param_set)) { + elems->mu_edca_param_set = data; + if (crc) + *crc = crc32_be(*crc, (void *)elem, + elem->datalen + 2); + } + break; + case WLAN_EID_EXT_HE_CAPABILITY: + elems->he_cap = data; + elems->he_cap_len = len; + break; + case WLAN_EID_EXT_HE_OPERATION: + if (len >= sizeof(*elems->he_operation) && + len == ieee80211_he_oper_size(data) - 1) + elems->he_operation = data; + break; + case WLAN_EID_EXT_UORA: + if (len == 1) + elems->uora_element = data; + break; + case WLAN_EID_EXT_MAX_CHANNEL_SWITCH_TIME: + if (len == 3) + elems->max_channel_switch_time = data; + break; + case WLAN_EID_EXT_MULTIPLE_BSSID_CONFIGURATION: + if (len == sizeof(*elems->mbssid_config_ie)) + elems->mbssid_config_ie = data; + break; + case WLAN_EID_EXT_HE_SPR: + if (len >= sizeof(*elems->he_spr) && + len >= ieee80211_he_spr_size(data)) + elems->he_spr = data; + break; + } +} + static u32 _ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action, struct ieee802_11_elems *elems, @@ -1220,33 +1265,9 @@ _ieee802_11_parse_elems_crc(const u8 *start, size_t len, bool action, elems->max_idle_period_ie = (void *)pos; break; case WLAN_EID_EXTENSION: - if (pos[0] == WLAN_EID_EXT_HE_MU_EDCA && - elen >= (sizeof(*elems->mu_edca_param_set) + 1)) { - elems->mu_edca_param_set = (void *)&pos[1]; - if (calc_crc) - crc = crc32_be(crc, pos - 2, elen + 2); - } else if (pos[0] == WLAN_EID_EXT_HE_CAPABILITY) { - elems->he_cap = (void *)&pos[1]; - elems->he_cap_len = elen - 1; - } else if (pos[0] == WLAN_EID_EXT_HE_OPERATION && - elen >= sizeof(*elems->he_operation) && - elen >= ieee80211_he_oper_size(&pos[1])) { - elems->he_operation = (void *)&pos[1]; - } else if (pos[0] == WLAN_EID_EXT_UORA && elen >= 1) { - elems->uora_element = (void *)&pos[1]; - } else if (pos[0] == - WLAN_EID_EXT_MAX_CHANNEL_SWITCH_TIME && - elen == 4) { - elems->max_channel_switch_time = pos + 1; - } else if (pos[0] == - WLAN_EID_EXT_MULTIPLE_BSSID_CONFIGURATION && - elen == 3) { - elems->mbssid_config_ie = (void *)&pos[1]; - } else if (pos[0] == WLAN_EID_EXT_HE_SPR && - elen >= sizeof(*elems->he_spr) && - elen >= ieee80211_he_spr_size(&pos[1])) { - elems->he_spr = (void *)&pos[1]; - } + ieee80211_parse_extension_element(calc_crc ? + &crc : NULL, + elem, elems); break; default: break; -- 2.30.2