From 5a21f0eae13515b9a0b6cc66dc5f1903c18afb17 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 28 Feb 2024 09:48:16 +0100 Subject: wifi: mac80211: hide element parsing internals Rework the data structures to hide element parsing internals from the users. Reviewed-by: Miriam Rachel Korenblit Link: https://msgid.link/20240228094902.19c610b529e2.Ie7ea2dcb6713911590ace6583a4748f32dc37df2@changeid Signed-off-by: Johannes Berg --- net/mac80211/ieee80211_i.h | 14 ------ net/mac80211/parse.c | 118 +++++++++++++++++++++++++++++---------------- net/mac80211/tests/elems.c | 4 +- 3 files changed, 78 insertions(+), 58 deletions(-) (limited to 'net/mac80211') diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index caee68cc8f14..da320799fbff 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -1766,12 +1766,6 @@ struct ieee802_11_elems { size_t ml_basic_len; size_t ml_reconf_len; - /* The basic Multi-Link element in the original elements */ - const struct element *ml_basic_elem; - - /* The reconfiguration Multi-Link element in the original elements */ - const struct element *ml_reconf_elem; - u8 ttlm_num; /* @@ -1784,14 +1778,6 @@ struct ieee802_11_elems { /* whether/which parse error occurred while retrieving these elements */ u8 parse_error; - - /* - * scratch buffer that can be used for various element parsing related - * tasks, e.g., element de-fragmentation etc. - */ - size_t scratch_len; - u8 *scratch_pos; - u8 scratch[] __counted_by(scratch_len); }; static inline struct ieee80211_local *hw_to_local( diff --git a/net/mac80211/parse.c b/net/mac80211/parse.c index 73e52504ed97..55e5497f8978 100644 --- a/net/mac80211/parse.c +++ b/net/mac80211/parse.c @@ -34,12 +34,32 @@ #include "led.h" #include "wep.h" +struct ieee80211_elems_parse { + /* must be first for kfree to work */ + struct ieee802_11_elems elems; + + /* The basic Multi-Link element in the original elements */ + const struct element *ml_basic_elem; + + /* The reconfiguration Multi-Link element in the original elements */ + const struct element *ml_reconf_elem; + + /* + * scratch buffer that can be used for various element parsing related + * tasks, e.g., element de-fragmentation etc. + */ + size_t scratch_len; + u8 *scratch_pos; + u8 scratch[] __counted_by(scratch_len); +}; + static void ieee80211_parse_extension_element(u32 *crc, const struct element *elem, - struct ieee802_11_elems *elems, + struct ieee80211_elems_parse *elems_parse, struct ieee80211_elems_parse_params *params) { + struct ieee802_11_elems *elems = &elems_parse->elems; const void *data = elem->data + 1; bool calc_crc = false; u8 len; @@ -129,15 +149,15 @@ ieee80211_parse_extension_element(u32 *crc, switch (le16_get_bits(mle->control, IEEE80211_ML_CONTROL_TYPE)) { case IEEE80211_ML_CONTROL_TYPE_BASIC: - if (elems->ml_basic_elem) { + if (elems_parse->ml_basic_elem) { elems->parse_error |= IEEE80211_PARSE_ERR_DUP_NEST_ML_BASIC; break; } - elems->ml_basic_elem = (void *)elem; + elems_parse->ml_basic_elem = elem; break; case IEEE80211_ML_CONTROL_TYPE_RECONF: - elems->ml_reconf_elem = (void *)elem; + elems_parse->ml_reconf_elem = elem; break; default: break; @@ -169,9 +189,10 @@ ieee80211_parse_extension_element(u32 *crc, static u32 _ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params, - struct ieee802_11_elems *elems, + struct ieee80211_elems_parse *elems_parse, const struct element *check_inherit) { + struct ieee802_11_elems *elems = &elems_parse->elems; const struct element *elem; bool calc_crc = params->filter != 0; DECLARE_BITMAP(seen_elems, 256); @@ -586,7 +607,8 @@ _ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params, case WLAN_EID_EXTENSION: ieee80211_parse_extension_element(calc_crc ? &crc : NULL, - elem, elems, params); + elem, elems_parse, + params); break; case WLAN_EID_S1G_CAPABILITIES: if (params->mode != IEEE80211_CONN_MODE_S1G) @@ -709,9 +731,11 @@ static size_t ieee802_11_find_bssid_profile(const u8 *start, size_t len, return found ? profile_len : 0; } -static void ieee80211_mle_get_sta_prof(struct ieee802_11_elems *elems, - u8 link_id) +static void +ieee80211_mle_get_sta_prof(struct ieee80211_elems_parse *elems_parse, + u8 link_id) { + struct ieee802_11_elems *elems = &elems_parse->elems; const struct ieee80211_multi_link_elem *ml = elems->ml_basic; ssize_t ml_len = elems->ml_basic_len; const struct element *sub; @@ -741,26 +765,27 @@ static void ieee80211_mle_get_sta_prof(struct ieee802_11_elems *elems, sta_prof_len = cfg80211_defragment_element(sub, (u8 *)ml, ml_len, - elems->scratch_pos, - elems->scratch + - elems->scratch_len - - elems->scratch_pos, + elems_parse->scratch_pos, + elems_parse->scratch + + elems_parse->scratch_len - + elems_parse->scratch_pos, IEEE80211_MLE_SUBELEM_FRAGMENT); if (sta_prof_len < 0) return; - elems->prof = (void *)elems->scratch_pos; + elems->prof = (void *)elems_parse->scratch_pos; elems->sta_prof_len = sta_prof_len; - elems->scratch_pos += sta_prof_len; + elems_parse->scratch_pos += sta_prof_len; return; } } -static void ieee80211_mle_parse_link(struct ieee802_11_elems *elems, +static void ieee80211_mle_parse_link(struct ieee80211_elems_parse *elems_parse, struct ieee80211_elems_parse_params *params) { + struct ieee802_11_elems *elems = &elems_parse->elems; struct ieee80211_mle_per_sta_profile *prof; struct ieee80211_elems_parse_params sub = { .mode = params->mode, @@ -772,26 +797,26 @@ static void ieee80211_mle_parse_link(struct ieee802_11_elems *elems, const struct element *non_inherit = NULL; const u8 *end; - ml_len = cfg80211_defragment_element(elems->ml_basic_elem, + ml_len = cfg80211_defragment_element(elems_parse->ml_basic_elem, elems->ie_start, elems->total_len, - elems->scratch_pos, - elems->scratch + - elems->scratch_len - - elems->scratch_pos, + elems_parse->scratch_pos, + elems_parse->scratch + + elems_parse->scratch_len - + elems_parse->scratch_pos, WLAN_EID_FRAGMENT); if (ml_len < 0) return; - elems->ml_basic = (const void *)elems->scratch_pos; + elems->ml_basic = (const void *)elems_parse->scratch_pos; elems->ml_basic_len = ml_len; - elems->scratch_pos += ml_len; + elems_parse->scratch_pos += ml_len; if (params->link_id == -1) return; - ieee80211_mle_get_sta_prof(elems, params->link_id); + ieee80211_mle_get_sta_prof(elems_parse, params->link_id); prof = elems->prof; if (!prof) @@ -816,57 +841,66 @@ static void ieee80211_mle_parse_link(struct ieee802_11_elems *elems, non_inherit = cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE, sub.start, sub.len); - _ieee802_11_parse_elems_full(&sub, elems, non_inherit); + _ieee802_11_parse_elems_full(&sub, elems_parse, non_inherit); } static void -ieee80211_mle_defrag_reconf(struct ieee802_11_elems *elems) +ieee80211_mle_defrag_reconf(struct ieee80211_elems_parse *elems_parse) { + struct ieee802_11_elems *elems = &elems_parse->elems; ssize_t ml_len; - ml_len = cfg80211_defragment_element(elems->ml_reconf_elem, + ml_len = cfg80211_defragment_element(elems_parse->ml_reconf_elem, elems->ie_start, elems->total_len, - elems->scratch_pos, - elems->scratch + - elems->scratch_len - - elems->scratch_pos, + elems_parse->scratch_pos, + elems_parse->scratch + + elems_parse->scratch_len - + elems_parse->scratch_pos, WLAN_EID_FRAGMENT); if (ml_len < 0) return; - elems->ml_reconf = (void *)elems->scratch_pos; + elems->ml_reconf = (void *)elems_parse->scratch_pos; elems->ml_reconf_len = ml_len; - elems->scratch_pos += ml_len; + elems_parse->scratch_pos += ml_len; } struct ieee802_11_elems * ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params) { + struct ieee80211_elems_parse *elems_parse; struct ieee802_11_elems *elems; const struct element *non_inherit = NULL; u8 *nontransmitted_profile; int nontransmitted_profile_len = 0; size_t scratch_len = 3 * params->len; - elems = kzalloc(struct_size(elems, scratch, scratch_len), GFP_ATOMIC); - if (!elems) + BUILD_BUG_ON(offsetof(typeof(*elems_parse), elems) != 0); + + elems_parse = kzalloc(struct_size(elems_parse, scratch, scratch_len), + GFP_ATOMIC); + if (!elems_parse) return NULL; + + elems_parse->scratch_len = scratch_len; + elems_parse->scratch_pos = elems_parse->scratch; + + elems = &elems_parse->elems; elems->ie_start = params->start; elems->total_len = params->len; - elems->scratch_len = scratch_len; - elems->scratch_pos = elems->scratch; - nontransmitted_profile = elems->scratch_pos; + nontransmitted_profile = elems_parse->scratch_pos; nontransmitted_profile_len = ieee802_11_find_bssid_profile(params->start, params->len, elems, params->bss, nontransmitted_profile); - elems->scratch_pos += nontransmitted_profile_len; + elems_parse->scratch_pos += nontransmitted_profile_len; non_inherit = cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE, nontransmitted_profile, nontransmitted_profile_len); - elems->crc = _ieee802_11_parse_elems_full(params, elems, non_inherit); + elems->crc = _ieee802_11_parse_elems_full(params, elems_parse, + non_inherit); /* Override with nontransmitted profile, if found */ if (nontransmitted_profile_len) { @@ -878,12 +912,12 @@ ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params) .link_id = params->link_id, }; - _ieee802_11_parse_elems_full(&sub, elems, NULL); + _ieee802_11_parse_elems_full(&sub, elems_parse, NULL); } - ieee80211_mle_parse_link(elems, params); + ieee80211_mle_parse_link(elems_parse, params); - ieee80211_mle_defrag_reconf(elems); + ieee80211_mle_defrag_reconf(elems_parse); if (elems->tim && !elems->parse_error) { const struct ieee80211_tim_ie *tim_ie = elems->tim; diff --git a/net/mac80211/tests/elems.c b/net/mac80211/tests/elems.c index 30fc0acb7ac2..a413ba29f759 100644 --- a/net/mac80211/tests/elems.c +++ b/net/mac80211/tests/elems.c @@ -2,7 +2,7 @@ /* * KUnit tests for element parsing * - * Copyright (C) 2023 Intel Corporation + * Copyright (C) 2023-2024 Intel Corporation */ #include #include "../ieee80211_i.h" @@ -69,7 +69,7 @@ static void mle_defrag(struct kunit *test) if (IS_ERR_OR_NULL(parsed)) goto free_skb; - KUNIT_EXPECT_NOT_NULL(test, parsed->ml_basic_elem); + KUNIT_EXPECT_NOT_NULL(test, parsed->ml_basic); KUNIT_EXPECT_EQ(test, parsed->ml_basic_len, 2 /* control */ + -- cgit