hostapd/src/common/ieee802_11_common.c

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/*
* IEEE 802.11 Common routines
* Copyright (c) 2002-2009, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "includes.h"
#include "common.h"
#include "ieee802_11_defs.h"
#include "ieee802_11_common.h"
static int ieee802_11_parse_vendor_specific(const u8 *pos, size_t elen,
struct ieee802_11_elems *elems,
int show_errors)
{
unsigned int oui;
/* first 3 bytes in vendor specific information element are the IEEE
* OUI of the vendor. The following byte is used a vendor specific
* sub-type. */
if (elen < 4) {
if (show_errors) {
wpa_printf(MSG_MSGDUMP, "short vendor specific "
"information element ignored (len=%lu)",
(unsigned long) elen);
}
return -1;
}
oui = WPA_GET_BE24(pos);
switch (oui) {
case OUI_MICROSOFT:
/* Microsoft/Wi-Fi information elements are further typed and
* subtyped */
switch (pos[3]) {
case 1:
/* Microsoft OUI (00:50:F2) with OUI Type 1:
* real WPA information element */
elems->wpa_ie = pos;
elems->wpa_ie_len = elen;
break;
case WMM_OUI_TYPE:
/* WMM information element */
if (elen < 5) {
wpa_printf(MSG_MSGDUMP, "short WMM "
"information element ignored "
"(len=%lu)",
(unsigned long) elen);
return -1;
}
switch (pos[4]) {
case WMM_OUI_SUBTYPE_INFORMATION_ELEMENT:
case WMM_OUI_SUBTYPE_PARAMETER_ELEMENT:
/*
* Share same pointer since only one of these
* is used and they start with same data.
* Length field can be used to distinguish the
* IEs.
*/
elems->wmm = pos;
elems->wmm_len = elen;
break;
case WMM_OUI_SUBTYPE_TSPEC_ELEMENT:
elems->wmm_tspec = pos;
elems->wmm_tspec_len = elen;
break;
default:
wpa_printf(MSG_EXCESSIVE, "unknown WMM "
"information element ignored "
"(subtype=%d len=%lu)",
pos[4], (unsigned long) elen);
return -1;
}
break;
case 4:
/* Wi-Fi Protected Setup (WPS) IE */
elems->wps_ie = pos;
elems->wps_ie_len = elen;
break;
default:
wpa_printf(MSG_EXCESSIVE, "Unknown Microsoft "
"information element ignored "
"(type=%d len=%lu)",
pos[3], (unsigned long) elen);
return -1;
}
break;
case OUI_WFA:
switch (pos[3]) {
case P2P_OUI_TYPE:
/* Wi-Fi Alliance - P2P IE */
elems->p2p = pos;
elems->p2p_len = elen;
break;
default:
wpa_printf(MSG_MSGDUMP, "Unknown WFA "
"information element ignored "
"(type=%d len=%lu)\n",
pos[3], (unsigned long) elen);
return -1;
}
break;
case OUI_BROADCOM:
switch (pos[3]) {
case VENDOR_HT_CAPAB_OUI_TYPE:
elems->vendor_ht_cap = pos;
elems->vendor_ht_cap_len = elen;
break;
default:
wpa_printf(MSG_EXCESSIVE, "Unknown Broadcom "
"information element ignored "
"(type=%d len=%lu)",
pos[3], (unsigned long) elen);
return -1;
}
break;
default:
wpa_printf(MSG_EXCESSIVE, "unknown vendor specific "
"information element ignored (vendor OUI "
"%02x:%02x:%02x len=%lu)",
pos[0], pos[1], pos[2], (unsigned long) elen);
return -1;
}
return 0;
}
/**
* ieee802_11_parse_elems - Parse information elements in management frames
* @start: Pointer to the start of IEs
* @len: Length of IE buffer in octets
* @elems: Data structure for parsed elements
* @show_errors: Whether to show parsing errors in debug log
* Returns: Parsing result
*/
ParseRes ieee802_11_parse_elems(const u8 *start, size_t len,
struct ieee802_11_elems *elems,
int show_errors)
{
size_t left = len;
const u8 *pos = start;
int unknown = 0;
os_memset(elems, 0, sizeof(*elems));
while (left >= 2) {
u8 id, elen;
id = *pos++;
elen = *pos++;
left -= 2;
if (elen > left) {
if (show_errors) {
wpa_printf(MSG_DEBUG, "IEEE 802.11 element "
"parse failed (id=%d elen=%d "
"left=%lu)",
id, elen, (unsigned long) left);
wpa_hexdump(MSG_MSGDUMP, "IEs", start, len);
}
return ParseFailed;
}
switch (id) {
case WLAN_EID_SSID:
elems->ssid = pos;
elems->ssid_len = elen;
break;
case WLAN_EID_SUPP_RATES:
elems->supp_rates = pos;
elems->supp_rates_len = elen;
break;
case WLAN_EID_FH_PARAMS:
elems->fh_params = pos;
elems->fh_params_len = elen;
break;
case WLAN_EID_DS_PARAMS:
elems->ds_params = pos;
elems->ds_params_len = elen;
break;
case WLAN_EID_CF_PARAMS:
elems->cf_params = pos;
elems->cf_params_len = elen;
break;
case WLAN_EID_TIM:
elems->tim = pos;
elems->tim_len = elen;
break;
case WLAN_EID_IBSS_PARAMS:
elems->ibss_params = pos;
elems->ibss_params_len = elen;
break;
case WLAN_EID_CHALLENGE:
elems->challenge = pos;
elems->challenge_len = elen;
break;
case WLAN_EID_ERP_INFO:
elems->erp_info = pos;
elems->erp_info_len = elen;
break;
case WLAN_EID_EXT_SUPP_RATES:
elems->ext_supp_rates = pos;
elems->ext_supp_rates_len = elen;
break;
case WLAN_EID_VENDOR_SPECIFIC:
if (ieee802_11_parse_vendor_specific(pos, elen,
elems,
show_errors))
unknown++;
break;
case WLAN_EID_RSN:
elems->rsn_ie = pos;
elems->rsn_ie_len = elen;
break;
case WLAN_EID_PWR_CAPABILITY:
elems->power_cap = pos;
elems->power_cap_len = elen;
break;
case WLAN_EID_SUPPORTED_CHANNELS:
elems->supp_channels = pos;
elems->supp_channels_len = elen;
break;
case WLAN_EID_MOBILITY_DOMAIN:
elems->mdie = pos;
elems->mdie_len = elen;
break;
case WLAN_EID_FAST_BSS_TRANSITION:
elems->ftie = pos;
elems->ftie_len = elen;
break;
case WLAN_EID_TIMEOUT_INTERVAL:
elems->timeout_int = pos;
elems->timeout_int_len = elen;
break;
case WLAN_EID_HT_CAP:
elems->ht_capabilities = pos;
elems->ht_capabilities_len = elen;
break;
case WLAN_EID_HT_OPERATION:
elems->ht_operation = pos;
elems->ht_operation_len = elen;
break;
default:
unknown++;
if (!show_errors)
break;
wpa_printf(MSG_MSGDUMP, "IEEE 802.11 element parse "
"ignored unknown element (id=%d elen=%d)",
id, elen);
break;
}
left -= elen;
pos += elen;
}
if (left)
return ParseFailed;
return unknown ? ParseUnknown : ParseOK;
}
int ieee802_11_ie_count(const u8 *ies, size_t ies_len)
{
int count = 0;
const u8 *pos, *end;
if (ies == NULL)
return 0;
pos = ies;
end = ies + ies_len;
while (pos + 2 <= end) {
if (pos + 2 + pos[1] > end)
break;
count++;
pos += 2 + pos[1];
}
return count;
}
struct wpabuf * ieee802_11_vendor_ie_concat(const u8 *ies, size_t ies_len,
u32 oui_type)
{
struct wpabuf *buf;
const u8 *end, *pos, *ie;
pos = ies;
end = ies + ies_len;
ie = NULL;
while (pos + 1 < end) {
if (pos + 2 + pos[1] > end)
return NULL;
if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
WPA_GET_BE32(&pos[2]) == oui_type) {
ie = pos;
break;
}
pos += 2 + pos[1];
}
if (ie == NULL)
return NULL; /* No specified vendor IE found */
buf = wpabuf_alloc(ies_len);
if (buf == NULL)
return NULL;
/*
* There may be multiple vendor IEs in the message, so need to
* concatenate their data fields.
*/
while (pos + 1 < end) {
if (pos + 2 + pos[1] > end)
break;
if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
WPA_GET_BE32(&pos[2]) == oui_type)
wpabuf_put_data(buf, pos + 6, pos[1] - 4);
pos += 2 + pos[1];
}
return buf;
}