diff --git a/src/common/ieee802_11_common.c b/src/common/ieee802_11_common.c index 679170d49..71876c084 100644 --- a/src/common/ieee802_11_common.c +++ b/src/common/ieee802_11_common.c @@ -206,6 +206,8 @@ static int ieee802_11_parse_extension(const u8 *pos, size_t elen, ext_id = *pos++; elen--; + elems->frag_ies.last_eid_ext = 0; + switch (ext_id) { case WLAN_EID_EXT_ASSOC_DELAY_INFO: if (elen != 1) @@ -295,10 +297,39 @@ static int ieee802_11_parse_extension(const u8 *pos, size_t elen, return -1; } + if (elen == 254) + elems->frag_ies.last_eid_ext = ext_id; + return 0; } +static void ieee802_11_parse_fragment(struct frag_ies_info *frag_ies, + const u8 *pos, u8 elen) +{ + if (frag_ies->n_frags >= MAX_NUM_FRAG_IES_SUPPORTED) { + wpa_printf(MSG_MSGDUMP, "Too many element fragments - skip"); + return; + } + + /* + * Note: while EID == 0 is a valid ID (SSID IE), it should not be + * fragmented. + */ + if (!frag_ies->last_eid) { + wpa_printf(MSG_MSGDUMP, + "Fragment without a valid last element - skip"); + return; + } + + frag_ies->frags[frag_ies->n_frags].ie = pos; + frag_ies->frags[frag_ies->n_frags].ie_len = elen; + frag_ies->frags[frag_ies->n_frags].eid = frag_ies->last_eid; + frag_ies->frags[frag_ies->n_frags].eid_ext = frag_ies->last_eid_ext; + frag_ies->n_frags++; +} + + /** * ieee802_11_parse_elems - Parse information elements in management frames * @start: Pointer to the start of IEs @@ -516,7 +547,7 @@ ParseRes ieee802_11_parse_elems(const u8 *start, size_t len, elems->dils_len = elen; break; case WLAN_EID_FRAGMENT: - /* TODO */ + ieee802_11_parse_fragment(&elems->frag_ies, pos, elen); break; case WLAN_EID_EXTENSION: if (ieee802_11_parse_extension(pos, elen, elems, @@ -532,6 +563,12 @@ ParseRes ieee802_11_parse_elems(const u8 *start, size_t len, id, elen); break; } + + if (id != WLAN_EID_FRAGMENT && elen == 255) + elems->frag_ies.last_eid = id; + + if (id == WLAN_EID_EXTENSION && !elems->frag_ies.last_eid_ext) + elems->frag_ies.last_eid = 0; } if (!for_each_element_completed(elem, start, len)) { @@ -2391,3 +2428,78 @@ int op_class_to_ch_width(u8 op_class) } return CHANWIDTH_USE_HT; } + + +struct wpabuf * ieee802_11_defrag_data(struct ieee802_11_elems *elems, + u8 eid, u8 eid_ext, + const u8 *data, u8 len) +{ + struct frag_ies_info *frag_ies = &elems->frag_ies; + struct wpabuf *buf; + unsigned int i; + + if (!elems || !data || !len) + return NULL; + + buf = wpabuf_alloc_copy(data, len); + if (!buf) + return NULL; + + for (i = 0; i < frag_ies->n_frags; i++) { + int ret; + + if (frag_ies->frags[i].eid != eid || + frag_ies->frags[i].eid_ext != eid_ext) + continue; + + ret = wpabuf_resize(&buf, frag_ies->frags[i].ie_len); + if (ret < 0) { + wpabuf_free(buf); + return NULL; + } + + /* Copy only the fragment data (without the EID and length) */ + wpabuf_put_data(buf, frag_ies->frags[i].ie, + frag_ies->frags[i].ie_len); + } + + return buf; +} + + +struct wpabuf * ieee802_11_defrag(struct ieee802_11_elems *elems, + u8 eid, u8 eid_ext) +{ + const u8 *data; + u8 len; + + /* + * TODO: Defragmentation mechanism can be supported for all IEs. For now + * handle only those that are used (or use ieee802_11_defrag_data()). + */ + switch (eid) { + case WLAN_EID_EXTENSION: + switch (eid_ext) { + case WLAN_EID_EXT_FILS_HLP_CONTAINER: + data = elems->fils_hlp; + len = elems->fils_hlp_len; + break; + case WLAN_EID_EXT_WRAPPED_DATA: + data = elems->wrapped_data; + len = elems->wrapped_data_len; + break; + default: + wpa_printf(MSG_DEBUG, + "Defragmentation not supported. eid_ext=%u", + eid_ext); + return NULL; + } + break; + default: + wpa_printf(MSG_DEBUG, + "Defragmentation not supported. eid=%u", eid); + return NULL; + } + + return ieee802_11_defrag_data(elems, eid, eid_ext, data, len); +} diff --git a/src/common/ieee802_11_common.h b/src/common/ieee802_11_common.h index bb2793d08..7994cd7d6 100644 --- a/src/common/ieee802_11_common.h +++ b/src/common/ieee802_11_common.h @@ -21,6 +21,7 @@ struct element { struct hostapd_hw_modes; #define MAX_NOF_MB_IES_SUPPORTED 5 +#define MAX_NUM_FRAG_IES_SUPPORTED 3 struct mb_ies_info { struct { @@ -30,6 +31,21 @@ struct mb_ies_info { u8 nof_ies; }; +struct frag_ies_info { + struct { + u8 eid; + u8 eid_ext; + const u8 *ie; + u8 ie_len; + } frags[MAX_NUM_FRAG_IES_SUPPORTED]; + + u8 n_frags; + + /* the last parsed element ID and element extension ID */ + u8 last_eid; + u8 last_eid_ext; +}; + /* Parsed Information Elements */ struct ieee802_11_elems { const u8 *ssid; @@ -151,6 +167,7 @@ struct ieee802_11_elems { u8 short_ssid_list_len; struct mb_ies_info mb_ies; + struct frag_ies_info frag_ies; }; typedef enum { ParseOK = 0, ParseUnknown = 1, ParseFailed = -1 } ParseRes; @@ -293,4 +310,10 @@ void hostapd_encode_edmg_chan(int edmg_enable, u8 edmg_channel, int ieee802_edmg_is_allowed(struct ieee80211_edmg_config allowed, struct ieee80211_edmg_config requested); +struct wpabuf * ieee802_11_defrag_data(struct ieee802_11_elems *elems, + u8 eid, u8 eid_ext, + const u8 *data, u8 len); +struct wpabuf * ieee802_11_defrag(struct ieee802_11_elems *elems, + u8 eid, u8 eid_ext); + #endif /* IEEE802_11_COMMON_H */