1179f831bSAndy Green /*
2179f831bSAndy Green * Radiotap parser
3179f831bSAndy Green *
4179f831bSAndy Green * Copyright 2007 Andy Green <andy@warmcat.com>
533e5a2f7SJohannes Berg * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
633e5a2f7SJohannes Berg *
733e5a2f7SJohannes Berg * This program is free software; you can redistribute it and/or modify
833e5a2f7SJohannes Berg * it under the terms of the GNU General Public License version 2 as
933e5a2f7SJohannes Berg * published by the Free Software Foundation.
1033e5a2f7SJohannes Berg *
1133e5a2f7SJohannes Berg * Alternatively, this software may be distributed under the terms of BSD
1233e5a2f7SJohannes Berg * license.
1333e5a2f7SJohannes Berg *
1433e5a2f7SJohannes Berg * See COPYING for more details.
15179f831bSAndy Green */
16179f831bSAndy Green
1794262316SNikitas Angelinas #include <linux/kernel.h>
18bc3b2d7fSPaul Gortmaker #include <linux/export.h>
19179f831bSAndy Green #include <net/cfg80211.h>
20179f831bSAndy Green #include <net/ieee80211_radiotap.h>
21179f831bSAndy Green #include <asm/unaligned.h>
22179f831bSAndy Green
23179f831bSAndy Green /* function prototypes and related defs are in include/net/cfg80211.h */
24179f831bSAndy Green
2533e5a2f7SJohannes Berg static const struct radiotap_align_size rtap_namespace_sizes[] = {
2633e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_TSFT] = { .align = 8, .size = 8, },
2733e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_FLAGS] = { .align = 1, .size = 1, },
2833e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_RATE] = { .align = 1, .size = 1, },
2933e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_CHANNEL] = { .align = 2, .size = 4, },
3033e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_FHSS] = { .align = 2, .size = 2, },
3133e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_DBM_ANTSIGNAL] = { .align = 1, .size = 1, },
3233e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_DBM_ANTNOISE] = { .align = 1, .size = 1, },
3333e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_LOCK_QUALITY] = { .align = 2, .size = 2, },
3433e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_TX_ATTENUATION] = { .align = 2, .size = 2, },
3533e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_DB_TX_ATTENUATION] = { .align = 2, .size = 2, },
3633e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_DBM_TX_POWER] = { .align = 1, .size = 1, },
3733e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_ANTENNA] = { .align = 1, .size = 1, },
3833e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_DB_ANTSIGNAL] = { .align = 1, .size = 1, },
3933e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_DB_ANTNOISE] = { .align = 1, .size = 1, },
4033e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_RX_FLAGS] = { .align = 2, .size = 2, },
4133e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_TX_FLAGS] = { .align = 2, .size = 2, },
4233e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_RTS_RETRIES] = { .align = 1, .size = 1, },
4333e5a2f7SJohannes Berg [IEEE80211_RADIOTAP_DATA_RETRIES] = { .align = 1, .size = 1, },
4448613eceSJohannes Berg [IEEE80211_RADIOTAP_MCS] = { .align = 1, .size = 3, },
4548613eceSJohannes Berg [IEEE80211_RADIOTAP_AMPDU_STATUS] = { .align = 4, .size = 8, },
467837a777SLorenzo Bianconi [IEEE80211_RADIOTAP_VHT] = { .align = 2, .size = 12, },
4733e5a2f7SJohannes Berg /*
4833e5a2f7SJohannes Berg * add more here as they are defined in radiotap.h
4933e5a2f7SJohannes Berg */
5033e5a2f7SJohannes Berg };
5133e5a2f7SJohannes Berg
5233e5a2f7SJohannes Berg static const struct ieee80211_radiotap_namespace radiotap_ns = {
5394262316SNikitas Angelinas .n_bits = ARRAY_SIZE(rtap_namespace_sizes),
5433e5a2f7SJohannes Berg .align_size = rtap_namespace_sizes,
5533e5a2f7SJohannes Berg };
5633e5a2f7SJohannes Berg
57179f831bSAndy Green /**
58179f831bSAndy Green * ieee80211_radiotap_iterator_init - radiotap parser iterator initialization
59179f831bSAndy Green * @iterator: radiotap_iterator to initialize
60179f831bSAndy Green * @radiotap_header: radiotap header to parse
61179f831bSAndy Green * @max_length: total length we can parse into (eg, whole packet length)
62211f2041SJohannes Berg * @vns: vendor namespaces to parse
63179f831bSAndy Green *
64179f831bSAndy Green * Returns: 0 or a negative error code if there is a problem.
65179f831bSAndy Green *
66179f831bSAndy Green * This function initializes an opaque iterator struct which can then
67179f831bSAndy Green * be passed to ieee80211_radiotap_iterator_next() to visit every radiotap
68179f831bSAndy Green * argument which is present in the header. It knows about extended
69179f831bSAndy Green * present headers and handles them.
70179f831bSAndy Green *
71179f831bSAndy Green * How to use:
72179f831bSAndy Green * call __ieee80211_radiotap_iterator_init() to init a semi-opaque iterator
73179f831bSAndy Green * struct ieee80211_radiotap_iterator (no need to init the struct beforehand)
74179f831bSAndy Green * checking for a good 0 return code. Then loop calling
75179f831bSAndy Green * __ieee80211_radiotap_iterator_next()... it returns either 0,
76179f831bSAndy Green * -ENOENT if there are no more args to parse, or -EINVAL if there is a problem.
77179f831bSAndy Green * The iterator's @this_arg member points to the start of the argument
78179f831bSAndy Green * associated with the current argument index that is present, which can be
79179f831bSAndy Green * found in the iterator's @this_arg_index member. This arg index corresponds
80179f831bSAndy Green * to the IEEE80211_RADIOTAP_... defines.
81179f831bSAndy Green *
82179f831bSAndy Green * Radiotap header length:
83179f831bSAndy Green * You can find the CPU-endian total radiotap header length in
84179f831bSAndy Green * iterator->max_length after executing ieee80211_radiotap_iterator_init()
85179f831bSAndy Green * successfully.
86179f831bSAndy Green *
87179f831bSAndy Green * Alignment Gotcha:
88179f831bSAndy Green * You must take care when dereferencing iterator.this_arg
89179f831bSAndy Green * for multibyte types... the pointer is not aligned. Use
90179f831bSAndy Green * get_unaligned((type *)iterator.this_arg) to dereference
91179f831bSAndy Green * iterator.this_arg for type "type" safely on all arches.
92179f831bSAndy Green *
93179f831bSAndy Green * Example code:
9466d495d0SMauro Carvalho Chehab * See Documentation/networking/radiotap-headers.rst
95179f831bSAndy Green */
96179f831bSAndy Green
ieee80211_radiotap_iterator_init(struct ieee80211_radiotap_iterator * iterator,struct ieee80211_radiotap_header * radiotap_header,int max_length,const struct ieee80211_radiotap_vendor_namespaces * vns)97179f831bSAndy Green int ieee80211_radiotap_iterator_init(
98179f831bSAndy Green struct ieee80211_radiotap_iterator *iterator,
99179f831bSAndy Green struct ieee80211_radiotap_header *radiotap_header,
10033e5a2f7SJohannes Berg int max_length, const struct ieee80211_radiotap_vendor_namespaces *vns)
101179f831bSAndy Green {
102f5563318SJohannes Berg /* check the radiotap header can actually be present */
103f5563318SJohannes Berg if (max_length < sizeof(struct ieee80211_radiotap_header))
104f5563318SJohannes Berg return -EINVAL;
105f5563318SJohannes Berg
106179f831bSAndy Green /* Linux only supports version 0 radiotap format */
107179f831bSAndy Green if (radiotap_header->it_version)
108179f831bSAndy Green return -EINVAL;
109179f831bSAndy Green
110179f831bSAndy Green /* sanity check for allowed length and radiotap length field */
111ae7245cbSHarvey Harrison if (max_length < get_unaligned_le16(&radiotap_header->it_len))
112179f831bSAndy Green return -EINVAL;
113179f831bSAndy Green
11433e5a2f7SJohannes Berg iterator->_rtheader = radiotap_header;
11533e5a2f7SJohannes Berg iterator->_max_length = get_unaligned_le16(&radiotap_header->it_len);
11633e5a2f7SJohannes Berg iterator->_arg_index = 0;
11733e5a2f7SJohannes Berg iterator->_bitmap_shifter = get_unaligned_le32(&radiotap_header->it_present);
118*8c89f7b3SKees Cook iterator->_arg = (uint8_t *)radiotap_header->it_optional;
11933e5a2f7SJohannes Berg iterator->_reset_on_ext = 0;
120*8c89f7b3SKees Cook iterator->_next_bitmap = radiotap_header->it_optional;
12133e5a2f7SJohannes Berg iterator->_vns = vns;
12233e5a2f7SJohannes Berg iterator->current_namespace = &radiotap_ns;
12333e5a2f7SJohannes Berg iterator->is_radiotap_ns = 1;
124179f831bSAndy Green
125179f831bSAndy Green /* find payload start allowing for extended bitmap(s) */
126179f831bSAndy Green
1275cafd378SKees Cook if (iterator->_bitmap_shifter & (BIT(IEEE80211_RADIOTAP_EXT))) {
128bd02cd25SJohannes Berg if ((unsigned long)iterator->_arg -
129bd02cd25SJohannes Berg (unsigned long)iterator->_rtheader + sizeof(uint32_t) >
130bd02cd25SJohannes Berg (unsigned long)iterator->_max_length)
131bd02cd25SJohannes Berg return -EINVAL;
13233e5a2f7SJohannes Berg while (get_unaligned_le32(iterator->_arg) &
1335cafd378SKees Cook (BIT(IEEE80211_RADIOTAP_EXT))) {
13433e5a2f7SJohannes Berg iterator->_arg += sizeof(uint32_t);
135179f831bSAndy Green
136179f831bSAndy Green /*
137179f831bSAndy Green * check for insanity where the present bitmaps
138179f831bSAndy Green * keep claiming to extend up to or even beyond the
139179f831bSAndy Green * stated radiotap header length
140179f831bSAndy Green */
141179f831bSAndy Green
14233e5a2f7SJohannes Berg if ((unsigned long)iterator->_arg -
143f5563318SJohannes Berg (unsigned long)iterator->_rtheader +
144f5563318SJohannes Berg sizeof(uint32_t) >
14533e5a2f7SJohannes Berg (unsigned long)iterator->_max_length)
146179f831bSAndy Green return -EINVAL;
147179f831bSAndy Green }
148179f831bSAndy Green
14933e5a2f7SJohannes Berg iterator->_arg += sizeof(uint32_t);
150179f831bSAndy Green
151179f831bSAndy Green /*
152179f831bSAndy Green * no need to check again for blowing past stated radiotap
153179f831bSAndy Green * header length, because ieee80211_radiotap_iterator_next
154179f831bSAndy Green * checks it before it is dereferenced
155179f831bSAndy Green */
156179f831bSAndy Green }
157179f831bSAndy Green
15833e5a2f7SJohannes Berg iterator->this_arg = iterator->_arg;
15933e5a2f7SJohannes Berg
160179f831bSAndy Green /* we are all initialized happily */
161179f831bSAndy Green
162179f831bSAndy Green return 0;
163179f831bSAndy Green }
164179f831bSAndy Green EXPORT_SYMBOL(ieee80211_radiotap_iterator_init);
165179f831bSAndy Green
find_ns(struct ieee80211_radiotap_iterator * iterator,uint32_t oui,uint8_t subns)16633e5a2f7SJohannes Berg static void find_ns(struct ieee80211_radiotap_iterator *iterator,
16733e5a2f7SJohannes Berg uint32_t oui, uint8_t subns)
16833e5a2f7SJohannes Berg {
16933e5a2f7SJohannes Berg int i;
17033e5a2f7SJohannes Berg
17133e5a2f7SJohannes Berg iterator->current_namespace = NULL;
17233e5a2f7SJohannes Berg
17333e5a2f7SJohannes Berg if (!iterator->_vns)
17433e5a2f7SJohannes Berg return;
17533e5a2f7SJohannes Berg
17633e5a2f7SJohannes Berg for (i = 0; i < iterator->_vns->n_ns; i++) {
17733e5a2f7SJohannes Berg if (iterator->_vns->ns[i].oui != oui)
17833e5a2f7SJohannes Berg continue;
17933e5a2f7SJohannes Berg if (iterator->_vns->ns[i].subns != subns)
18033e5a2f7SJohannes Berg continue;
18133e5a2f7SJohannes Berg
18233e5a2f7SJohannes Berg iterator->current_namespace = &iterator->_vns->ns[i];
18333e5a2f7SJohannes Berg break;
18433e5a2f7SJohannes Berg }
18533e5a2f7SJohannes Berg }
18633e5a2f7SJohannes Berg
18733e5a2f7SJohannes Berg
188179f831bSAndy Green
189179f831bSAndy Green /**
190179f831bSAndy Green * ieee80211_radiotap_iterator_next - return next radiotap parser iterator arg
191179f831bSAndy Green * @iterator: radiotap_iterator to move to next arg (if any)
192179f831bSAndy Green *
193179f831bSAndy Green * Returns: 0 if there is an argument to handle,
194179f831bSAndy Green * -ENOENT if there are no more args or -EINVAL
195179f831bSAndy Green * if there is something else wrong.
196179f831bSAndy Green *
197179f831bSAndy Green * This function provides the next radiotap arg index (IEEE80211_RADIOTAP_*)
198179f831bSAndy Green * in @this_arg_index and sets @this_arg to point to the
199179f831bSAndy Green * payload for the field. It takes care of alignment handling and extended
200179f831bSAndy Green * present fields. @this_arg can be changed by the caller (eg,
201179f831bSAndy Green * incremented to move inside a compound argument like
202179f831bSAndy Green * IEEE80211_RADIOTAP_CHANNEL). The args pointed to are in
203179f831bSAndy Green * little-endian format whatever the endianess of your CPU.
204179f831bSAndy Green *
205179f831bSAndy Green * Alignment Gotcha:
206179f831bSAndy Green * You must take care when dereferencing iterator.this_arg
207179f831bSAndy Green * for multibyte types... the pointer is not aligned. Use
208179f831bSAndy Green * get_unaligned((type *)iterator.this_arg) to dereference
209179f831bSAndy Green * iterator.this_arg for type "type" safely on all arches.
210179f831bSAndy Green */
211179f831bSAndy Green
ieee80211_radiotap_iterator_next(struct ieee80211_radiotap_iterator * iterator)212179f831bSAndy Green int ieee80211_radiotap_iterator_next(
213179f831bSAndy Green struct ieee80211_radiotap_iterator *iterator)
214179f831bSAndy Green {
21533e5a2f7SJohannes Berg while (1) {
216179f831bSAndy Green int hit = 0;
2179ebad4abSJohannes Berg int pad, align, size, subns;
21833e5a2f7SJohannes Berg uint32_t oui;
219179f831bSAndy Green
22033e5a2f7SJohannes Berg /* if no more EXT bits, that's it */
22133e5a2f7SJohannes Berg if ((iterator->_arg_index % 32) == IEEE80211_RADIOTAP_EXT &&
22233e5a2f7SJohannes Berg !(iterator->_bitmap_shifter & 1))
22333e5a2f7SJohannes Berg return -ENOENT;
22433e5a2f7SJohannes Berg
22533e5a2f7SJohannes Berg if (!(iterator->_bitmap_shifter & 1))
226179f831bSAndy Green goto next_entry; /* arg not present */
227179f831bSAndy Green
22833e5a2f7SJohannes Berg /* get alignment/size of data */
22933e5a2f7SJohannes Berg switch (iterator->_arg_index % 32) {
23033e5a2f7SJohannes Berg case IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE:
23133e5a2f7SJohannes Berg case IEEE80211_RADIOTAP_EXT:
23233e5a2f7SJohannes Berg align = 1;
23333e5a2f7SJohannes Berg size = 0;
23433e5a2f7SJohannes Berg break;
23533e5a2f7SJohannes Berg case IEEE80211_RADIOTAP_VENDOR_NAMESPACE:
23633e5a2f7SJohannes Berg align = 2;
23733e5a2f7SJohannes Berg size = 6;
23833e5a2f7SJohannes Berg break;
23933e5a2f7SJohannes Berg default:
24033e5a2f7SJohannes Berg if (!iterator->current_namespace ||
24133e5a2f7SJohannes Berg iterator->_arg_index >= iterator->current_namespace->n_bits) {
24233e5a2f7SJohannes Berg if (iterator->current_namespace == &radiotap_ns)
24333e5a2f7SJohannes Berg return -ENOENT;
24433e5a2f7SJohannes Berg align = 0;
24533e5a2f7SJohannes Berg } else {
24633e5a2f7SJohannes Berg align = iterator->current_namespace->align_size[iterator->_arg_index].align;
24733e5a2f7SJohannes Berg size = iterator->current_namespace->align_size[iterator->_arg_index].size;
24833e5a2f7SJohannes Berg }
24933e5a2f7SJohannes Berg if (!align) {
25033e5a2f7SJohannes Berg /* skip all subsequent data */
25133e5a2f7SJohannes Berg iterator->_arg = iterator->_next_ns_data;
25233e5a2f7SJohannes Berg /* give up on this namespace */
25333e5a2f7SJohannes Berg iterator->current_namespace = NULL;
25433e5a2f7SJohannes Berg goto next_entry;
25533e5a2f7SJohannes Berg }
25633e5a2f7SJohannes Berg break;
25733e5a2f7SJohannes Berg }
25833e5a2f7SJohannes Berg
259179f831bSAndy Green /*
260179f831bSAndy Green * arg is present, account for alignment padding
261179f831bSAndy Green *
26233e5a2f7SJohannes Berg * Note that these alignments are relative to the start
26333e5a2f7SJohannes Berg * of the radiotap header. There is no guarantee
264179f831bSAndy Green * that the radiotap header itself is aligned on any
265179f831bSAndy Green * kind of boundary.
266179f831bSAndy Green *
26733e5a2f7SJohannes Berg * The above is why get_unaligned() is used to dereference
26833e5a2f7SJohannes Berg * multibyte elements from the radiotap area.
269179f831bSAndy Green */
270179f831bSAndy Green
27133e5a2f7SJohannes Berg pad = ((unsigned long)iterator->_arg -
27233e5a2f7SJohannes Berg (unsigned long)iterator->_rtheader) & (align - 1);
273179f831bSAndy Green
274179f831bSAndy Green if (pad)
27533e5a2f7SJohannes Berg iterator->_arg += align - pad;
276179f831bSAndy Green
2779ebad4abSJohannes Berg if (iterator->_arg_index % 32 == IEEE80211_RADIOTAP_VENDOR_NAMESPACE) {
2789ebad4abSJohannes Berg int vnslen;
2799ebad4abSJohannes Berg
2809ebad4abSJohannes Berg if ((unsigned long)iterator->_arg + size -
2819ebad4abSJohannes Berg (unsigned long)iterator->_rtheader >
2829ebad4abSJohannes Berg (unsigned long)iterator->_max_length)
2839ebad4abSJohannes Berg return -EINVAL;
2849ebad4abSJohannes Berg
2859ebad4abSJohannes Berg oui = (*iterator->_arg << 16) |
2869ebad4abSJohannes Berg (*(iterator->_arg + 1) << 8) |
2879ebad4abSJohannes Berg *(iterator->_arg + 2);
2889ebad4abSJohannes Berg subns = *(iterator->_arg + 3);
2899ebad4abSJohannes Berg
2909ebad4abSJohannes Berg find_ns(iterator, oui, subns);
2919ebad4abSJohannes Berg
2929ebad4abSJohannes Berg vnslen = get_unaligned_le16(iterator->_arg + 4);
2939ebad4abSJohannes Berg iterator->_next_ns_data = iterator->_arg + size + vnslen;
2949ebad4abSJohannes Berg if (!iterator->current_namespace)
2959ebad4abSJohannes Berg size += vnslen;
2969ebad4abSJohannes Berg }
2979ebad4abSJohannes Berg
298179f831bSAndy Green /*
299179f831bSAndy Green * this is what we will return to user, but we need to
300179f831bSAndy Green * move on first so next call has something fresh to test
301179f831bSAndy Green */
30233e5a2f7SJohannes Berg iterator->this_arg_index = iterator->_arg_index;
30333e5a2f7SJohannes Berg iterator->this_arg = iterator->_arg;
30433e5a2f7SJohannes Berg iterator->this_arg_size = size;
305179f831bSAndy Green
306179f831bSAndy Green /* internally move on the size of this arg */
30733e5a2f7SJohannes Berg iterator->_arg += size;
308179f831bSAndy Green
309179f831bSAndy Green /*
310179f831bSAndy Green * check for insanity where we are given a bitmap that
311179f831bSAndy Green * claims to have more arg content than the length of the
312179f831bSAndy Green * radiotap section. We will normally end up equalling this
313179f831bSAndy Green * max_length on the last arg, never exceeding it.
314179f831bSAndy Green */
315179f831bSAndy Green
31633e5a2f7SJohannes Berg if ((unsigned long)iterator->_arg -
31733e5a2f7SJohannes Berg (unsigned long)iterator->_rtheader >
31833e5a2f7SJohannes Berg (unsigned long)iterator->_max_length)
319179f831bSAndy Green return -EINVAL;
320179f831bSAndy Green
32133e5a2f7SJohannes Berg /* these special ones are valid in each bitmap word */
32233e5a2f7SJohannes Berg switch (iterator->_arg_index % 32) {
32333e5a2f7SJohannes Berg case IEEE80211_RADIOTAP_VENDOR_NAMESPACE:
32433e5a2f7SJohannes Berg iterator->_reset_on_ext = 1;
32533e5a2f7SJohannes Berg
32633e5a2f7SJohannes Berg iterator->is_radiotap_ns = 0;
3279ebad4abSJohannes Berg /*
3289ebad4abSJohannes Berg * If parser didn't register this vendor
3299ebad4abSJohannes Berg * namespace with us, allow it to show it
3309ebad4abSJohannes Berg * as 'raw. Do do that, set argument index
3319ebad4abSJohannes Berg * to vendor namespace.
3329ebad4abSJohannes Berg */
33333e5a2f7SJohannes Berg iterator->this_arg_index =
33433e5a2f7SJohannes Berg IEEE80211_RADIOTAP_VENDOR_NAMESPACE;
3359ebad4abSJohannes Berg if (!iterator->current_namespace)
33633e5a2f7SJohannes Berg hit = 1;
3379ebad4abSJohannes Berg goto next_entry;
33833e5a2f7SJohannes Berg case IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE:
33933e5a2f7SJohannes Berg iterator->_reset_on_ext = 1;
34033e5a2f7SJohannes Berg iterator->current_namespace = &radiotap_ns;
34133e5a2f7SJohannes Berg iterator->is_radiotap_ns = 1;
3429ebad4abSJohannes Berg goto next_entry;
34333e5a2f7SJohannes Berg case IEEE80211_RADIOTAP_EXT:
34433e5a2f7SJohannes Berg /*
34533e5a2f7SJohannes Berg * bit 31 was set, there is more
34633e5a2f7SJohannes Berg * -- move to next u32 bitmap
34733e5a2f7SJohannes Berg */
34833e5a2f7SJohannes Berg iterator->_bitmap_shifter =
34933e5a2f7SJohannes Berg get_unaligned_le32(iterator->_next_bitmap);
35033e5a2f7SJohannes Berg iterator->_next_bitmap++;
35133e5a2f7SJohannes Berg if (iterator->_reset_on_ext)
35233e5a2f7SJohannes Berg iterator->_arg_index = 0;
35333e5a2f7SJohannes Berg else
35433e5a2f7SJohannes Berg iterator->_arg_index++;
35533e5a2f7SJohannes Berg iterator->_reset_on_ext = 0;
35633e5a2f7SJohannes Berg break;
35733e5a2f7SJohannes Berg default:
35833e5a2f7SJohannes Berg /* we've got a hit! */
35933e5a2f7SJohannes Berg hit = 1;
360179f831bSAndy Green next_entry:
36133e5a2f7SJohannes Berg iterator->_bitmap_shifter >>= 1;
36233e5a2f7SJohannes Berg iterator->_arg_index++;
36333e5a2f7SJohannes Berg }
364179f831bSAndy Green
365179f831bSAndy Green /* if we found a valid arg earlier, return it now */
366179f831bSAndy Green if (hit)
367179f831bSAndy Green return 0;
368179f831bSAndy Green }
369179f831bSAndy Green }
370179f831bSAndy Green EXPORT_SYMBOL(ieee80211_radiotap_iterator_next);
371