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diff --git a/package/hostapd/files/radiotap.c b/package/hostapd/files/radiotap.c
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-/*
- * Radiotap parser
- *
- * Copyright 2007 Andy Green <andy@warmcat.com>
- *
- * 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.
- *
- *
- * Modified for userspace by Johannes Berg <johannes@sipsolutions.net>
- * I only modified some things on top to ease syncing should bugs be found.
- */
-
-#include "includes.h"
-
-#include "common.h"
-#include "radiotap_iter.h"
-
-#define le16_to_cpu le_to_host16
-#define le32_to_cpu le_to_host32
-#define __le32 uint32_t
-#define ulong unsigned long
-#define unlikely(cond) (cond)
-#define get_unaligned(p) \
-({ \
- struct packed_dummy_struct { \
- typeof(*(p)) __val; \
- } __attribute__((packed)) *__ptr = (void *) (p); \
- \
- __ptr->__val; \
-})
-
-/* function prototypes and related defs are in radiotap_iter.h */
-
-/**
- * ieee80211_radiotap_iterator_init - radiotap parser iterator initialization
- * @iterator: radiotap_iterator to initialize
- * @radiotap_header: radiotap header to parse
- * @max_length: total length we can parse into (eg, whole packet length)
- *
- * Returns: 0 or a negative error code if there is a problem.
- *
- * This function initializes an opaque iterator struct which can then
- * be passed to ieee80211_radiotap_iterator_next() to visit every radiotap
- * argument which is present in the header. It knows about extended
- * present headers and handles them.
- *
- * How to use:
- * call __ieee80211_radiotap_iterator_init() to init a semi-opaque iterator
- * struct ieee80211_radiotap_iterator (no need to init the struct beforehand)
- * checking for a good 0 return code. Then loop calling
- * __ieee80211_radiotap_iterator_next()... it returns either 0,
- * -ENOENT if there are no more args to parse, or -EINVAL if there is a problem.
- * The iterator's @this_arg member points to the start of the argument
- * associated with the current argument index that is present, which can be
- * found in the iterator's @this_arg_index member. This arg index corresponds
- * to the IEEE80211_RADIOTAP_... defines.
- *
- * Radiotap header length:
- * You can find the CPU-endian total radiotap header length in
- * iterator->max_length after executing ieee80211_radiotap_iterator_init()
- * successfully.
- *
- * Alignment Gotcha:
- * You must take care when dereferencing iterator.this_arg
- * for multibyte types... the pointer is not aligned. Use
- * get_unaligned((type *)iterator.this_arg) to dereference
- * iterator.this_arg for type "type" safely on all arches.
- *
- * Example code:
- * See Documentation/networking/radiotap-headers.txt
- */
-
-int ieee80211_radiotap_iterator_init(
- struct ieee80211_radiotap_iterator *iterator,
- struct ieee80211_radiotap_header *radiotap_header,
- int max_length)
-{
- /* Linux only supports version 0 radiotap format */
- if (radiotap_header->it_version)
- return -EINVAL;
-
- /* sanity check for allowed length and radiotap length field */
- if (max_length < le16_to_cpu(get_unaligned(&radiotap_header->it_len)))
- return -EINVAL;
-
- iterator->rtheader = radiotap_header;
- iterator->max_length = le16_to_cpu(get_unaligned(
- &radiotap_header->it_len));
- iterator->arg_index = 0;
- iterator->bitmap_shifter = le32_to_cpu(get_unaligned(
- &radiotap_header->it_present));
- iterator->arg = (u8 *)radiotap_header + sizeof(*radiotap_header);
- iterator->this_arg = NULL;
-
- /* find payload start allowing for extended bitmap(s) */
-
- if (unlikely(iterator->bitmap_shifter & (1<<IEEE80211_RADIOTAP_EXT))) {
- while (le32_to_cpu(get_unaligned((__le32 *)iterator->arg)) &
- (1<<IEEE80211_RADIOTAP_EXT)) {
- iterator->arg += sizeof(u32);
-
- /*
- * check for insanity where the present bitmaps
- * keep claiming to extend up to or even beyond the
- * stated radiotap header length
- */
-
- if (((ulong)iterator->arg - (ulong)iterator->rtheader)
- > (ulong)iterator->max_length)
- return -EINVAL;
- }
-
- iterator->arg += sizeof(u32);
-
- /*
- * no need to check again for blowing past stated radiotap
- * header length, because ieee80211_radiotap_iterator_next
- * checks it before it is dereferenced
- */
- }
-
- /* we are all initialized happily */
-
- return 0;
-}
-
-
-/**
- * ieee80211_radiotap_iterator_next - return next radiotap parser iterator arg
- * @iterator: radiotap_iterator to move to next arg (if any)
- *
- * Returns: 0 if there is an argument to handle,
- * -ENOENT if there are no more args or -EINVAL
- * if there is something else wrong.
- *
- * This function provides the next radiotap arg index (IEEE80211_RADIOTAP_*)
- * in @this_arg_index and sets @this_arg to point to the
- * payload for the field. It takes care of alignment handling and extended
- * present fields. @this_arg can be changed by the caller (eg,
- * incremented to move inside a compound argument like
- * IEEE80211_RADIOTAP_CHANNEL). The args pointed to are in
- * little-endian format whatever the endianess of your CPU.
- *
- * Alignment Gotcha:
- * You must take care when dereferencing iterator.this_arg
- * for multibyte types... the pointer is not aligned. Use
- * get_unaligned((type *)iterator.this_arg) to dereference
- * iterator.this_arg for type "type" safely on all arches.
- */
-
-int ieee80211_radiotap_iterator_next(
- struct ieee80211_radiotap_iterator *iterator)
-{
-
- /*
- * small length lookup table for all radiotap types we heard of
- * starting from b0 in the bitmap, so we can walk the payload
- * area of the radiotap header
- *
- * There is a requirement to pad args, so that args
- * of a given length must begin at a boundary of that length
- * -- but note that compound args are allowed (eg, 2 x u16
- * for IEEE80211_RADIOTAP_CHANNEL) so total arg length is not
- * a reliable indicator of alignment requirement.
- *
- * upper nybble: content alignment for arg
- * lower nybble: content length for arg
- */
-
- static const u8 rt_sizes[] = {
- [IEEE80211_RADIOTAP_TSFT] = 0x88,
- [IEEE80211_RADIOTAP_FLAGS] = 0x11,
- [IEEE80211_RADIOTAP_RATE] = 0x11,
- [IEEE80211_RADIOTAP_CHANNEL] = 0x24,
- [IEEE80211_RADIOTAP_FHSS] = 0x22,
- [IEEE80211_RADIOTAP_DBM_ANTSIGNAL] = 0x11,
- [IEEE80211_RADIOTAP_DBM_ANTNOISE] = 0x11,
- [IEEE80211_RADIOTAP_LOCK_QUALITY] = 0x22,
- [IEEE80211_RADIOTAP_TX_ATTENUATION] = 0x22,
- [IEEE80211_RADIOTAP_DB_TX_ATTENUATION] = 0x22,
- [IEEE80211_RADIOTAP_DBM_TX_POWER] = 0x11,
- [IEEE80211_RADIOTAP_ANTENNA] = 0x11,
- [IEEE80211_RADIOTAP_DB_ANTSIGNAL] = 0x11,
- [IEEE80211_RADIOTAP_DB_ANTNOISE] = 0x11,
- [IEEE80211_RADIOTAP_RX_FLAGS] = 0x22,
- [IEEE80211_RADIOTAP_TX_FLAGS] = 0x22,
- [IEEE80211_RADIOTAP_RTS_RETRIES] = 0x11,
- [IEEE80211_RADIOTAP_DATA_RETRIES] = 0x11,
- /*
- * add more here as they are defined in
- * include/net/ieee80211_radiotap.h
- */
- };
-
- /*
- * for every radiotap entry we can at
- * least skip (by knowing the length)...
- */
-
- while (iterator->arg_index < (int) sizeof(rt_sizes)) {
- int hit = 0;
- int pad;
-
- if (!(iterator->bitmap_shifter & 1))
- goto next_entry; /* arg not present */
-
- /*
- * arg is present, account for alignment padding
- * 8-bit args can be at any alignment
- * 16-bit args must start on 16-bit boundary
- * 32-bit args must start on 32-bit boundary
- * 64-bit args must start on 64-bit boundary
- *
- * note that total arg size can differ from alignment of
- * elements inside arg, so we use upper nybble of length
- * table to base alignment on
- *
- * also note: these alignments are ** relative to the
- * start of the radiotap header **. There is no guarantee
- * that the radiotap header itself is aligned on any
- * kind of boundary.
- *
- * the above is why get_unaligned() is used to dereference
- * multibyte elements from the radiotap area
- */
-
- pad = (((ulong)iterator->arg) -
- ((ulong)iterator->rtheader)) &
- ((rt_sizes[iterator->arg_index] >> 4) - 1);
-
- if (pad)
- iterator->arg +=
- (rt_sizes[iterator->arg_index] >> 4) - pad;
-
- /*
- * this is what we will return to user, but we need to
- * move on first so next call has something fresh to test
- */
- iterator->this_arg_index = iterator->arg_index;
- iterator->this_arg = iterator->arg;
- hit = 1;
-
- /* internally move on the size of this arg */
- iterator->arg += rt_sizes[iterator->arg_index] & 0x0f;
-
- /*
- * check for insanity where we are given a bitmap that
- * claims to have more arg content than the length of the
- * radiotap section. We will normally end up equalling this
- * max_length on the last arg, never exceeding it.
- */
-
- if (((ulong)iterator->arg - (ulong)iterator->rtheader) >
- (ulong) iterator->max_length)
- return -EINVAL;
-
- next_entry:
- iterator->arg_index++;
- if (unlikely((iterator->arg_index & 31) == 0)) {
- /* completed current u32 bitmap */
- if (iterator->bitmap_shifter & 1) {
- /* b31 was set, there is more */
- /* move to next u32 bitmap */
- iterator->bitmap_shifter = le32_to_cpu(
- get_unaligned(iterator->next_bitmap));
- iterator->next_bitmap++;
- } else
- /* no more bitmaps: end */
- iterator->arg_index = sizeof(rt_sizes);
- } else /* just try the next bit */
- iterator->bitmap_shifter >>= 1;
-
- /* if we found a valid arg earlier, return it now */
- if (hit)
- return 0;
- }
-
- /* we don't know how to handle any more args, we're done */
- return -ENOENT;
-}