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@@ -1,287 +0,0 @@
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-/*
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- * Radiotap parser
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- *
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- * Copyright 2007 Andy Green <andy@warmcat.com>
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- *
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- * This program is free software; you can redistribute it and/or modify
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- * it under the terms of the GNU General Public License version 2 as
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- * published by the Free Software Foundation.
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- *
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- * Alternatively, this software may be distributed under the terms of BSD
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- * license.
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- *
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- * See README and COPYING for more details.
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- *
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- *
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- * Modified for userspace by Johannes Berg <johannes@sipsolutions.net>
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- * I only modified some things on top to ease syncing should bugs be found.
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- */
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-
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-#include "includes.h"
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-
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-#include "common.h"
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-#include "radiotap_iter.h"
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-
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-#define le16_to_cpu le_to_host16
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-#define le32_to_cpu le_to_host32
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-#define __le32 uint32_t
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-#define ulong unsigned long
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-#define unlikely(cond) (cond)
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-#define get_unaligned(p) \
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-({ \
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- struct packed_dummy_struct { \
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- typeof(*(p)) __val; \
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- } __attribute__((packed)) *__ptr = (void *) (p); \
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- \
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- __ptr->__val; \
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-})
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-
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-/* function prototypes and related defs are in radiotap_iter.h */
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-
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-/**
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- * ieee80211_radiotap_iterator_init - radiotap parser iterator initialization
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- * @iterator: radiotap_iterator to initialize
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- * @radiotap_header: radiotap header to parse
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- * @max_length: total length we can parse into (eg, whole packet length)
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- *
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- * Returns: 0 or a negative error code if there is a problem.
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- *
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- * This function initializes an opaque iterator struct which can then
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- * be passed to ieee80211_radiotap_iterator_next() to visit every radiotap
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- * argument which is present in the header. It knows about extended
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- * present headers and handles them.
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- *
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- * How to use:
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- * call __ieee80211_radiotap_iterator_init() to init a semi-opaque iterator
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- * struct ieee80211_radiotap_iterator (no need to init the struct beforehand)
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- * checking for a good 0 return code. Then loop calling
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- * __ieee80211_radiotap_iterator_next()... it returns either 0,
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- * -ENOENT if there are no more args to parse, or -EINVAL if there is a problem.
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- * The iterator's @this_arg member points to the start of the argument
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- * associated with the current argument index that is present, which can be
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- * found in the iterator's @this_arg_index member. This arg index corresponds
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- * to the IEEE80211_RADIOTAP_... defines.
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- *
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- * Radiotap header length:
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- * You can find the CPU-endian total radiotap header length in
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- * iterator->max_length after executing ieee80211_radiotap_iterator_init()
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- * successfully.
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- *
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- * Alignment Gotcha:
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- * You must take care when dereferencing iterator.this_arg
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- * for multibyte types... the pointer is not aligned. Use
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- * get_unaligned((type *)iterator.this_arg) to dereference
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- * iterator.this_arg for type "type" safely on all arches.
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- *
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- * Example code:
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- * See Documentation/networking/radiotap-headers.txt
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- */
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-
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-int ieee80211_radiotap_iterator_init(
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- struct ieee80211_radiotap_iterator *iterator,
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- struct ieee80211_radiotap_header *radiotap_header,
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- int max_length)
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-{
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- /* Linux only supports version 0 radiotap format */
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- if (radiotap_header->it_version)
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- return -EINVAL;
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-
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- /* sanity check for allowed length and radiotap length field */
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- if (max_length < le16_to_cpu(get_unaligned(&radiotap_header->it_len)))
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- return -EINVAL;
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-
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- iterator->rtheader = radiotap_header;
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- iterator->max_length = le16_to_cpu(get_unaligned(
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- &radiotap_header->it_len));
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- iterator->arg_index = 0;
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- iterator->bitmap_shifter = le32_to_cpu(get_unaligned(
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- &radiotap_header->it_present));
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- iterator->arg = (u8 *)radiotap_header + sizeof(*radiotap_header);
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- iterator->this_arg = NULL;
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-
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- /* find payload start allowing for extended bitmap(s) */
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-
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- if (unlikely(iterator->bitmap_shifter & (1<<IEEE80211_RADIOTAP_EXT))) {
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- while (le32_to_cpu(get_unaligned((__le32 *)iterator->arg)) &
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- (1<<IEEE80211_RADIOTAP_EXT)) {
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- iterator->arg += sizeof(u32);
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-
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- /*
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- * check for insanity where the present bitmaps
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- * keep claiming to extend up to or even beyond the
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- * stated radiotap header length
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- */
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-
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- if (((ulong)iterator->arg - (ulong)iterator->rtheader)
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- > (ulong)iterator->max_length)
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- return -EINVAL;
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- }
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-
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- iterator->arg += sizeof(u32);
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-
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- /*
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- * no need to check again for blowing past stated radiotap
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- * header length, because ieee80211_radiotap_iterator_next
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- * checks it before it is dereferenced
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- */
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- }
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-
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- /* we are all initialized happily */
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-
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- return 0;
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-}
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-
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-
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-/**
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- * ieee80211_radiotap_iterator_next - return next radiotap parser iterator arg
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- * @iterator: radiotap_iterator to move to next arg (if any)
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- *
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- * Returns: 0 if there is an argument to handle,
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- * -ENOENT if there are no more args or -EINVAL
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- * if there is something else wrong.
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- *
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- * This function provides the next radiotap arg index (IEEE80211_RADIOTAP_*)
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- * in @this_arg_index and sets @this_arg to point to the
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- * payload for the field. It takes care of alignment handling and extended
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- * present fields. @this_arg can be changed by the caller (eg,
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- * incremented to move inside a compound argument like
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- * IEEE80211_RADIOTAP_CHANNEL). The args pointed to are in
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- * little-endian format whatever the endianess of your CPU.
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- *
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- * Alignment Gotcha:
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- * You must take care when dereferencing iterator.this_arg
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- * for multibyte types... the pointer is not aligned. Use
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- * get_unaligned((type *)iterator.this_arg) to dereference
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- * iterator.this_arg for type "type" safely on all arches.
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- */
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-
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-int ieee80211_radiotap_iterator_next(
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- struct ieee80211_radiotap_iterator *iterator)
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-{
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-
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- /*
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- * small length lookup table for all radiotap types we heard of
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- * starting from b0 in the bitmap, so we can walk the payload
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- * area of the radiotap header
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- *
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- * There is a requirement to pad args, so that args
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- * of a given length must begin at a boundary of that length
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- * -- but note that compound args are allowed (eg, 2 x u16
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- * for IEEE80211_RADIOTAP_CHANNEL) so total arg length is not
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- * a reliable indicator of alignment requirement.
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- *
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- * upper nybble: content alignment for arg
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- * lower nybble: content length for arg
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- */
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-
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- static const u8 rt_sizes[] = {
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- [IEEE80211_RADIOTAP_TSFT] = 0x88,
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- [IEEE80211_RADIOTAP_FLAGS] = 0x11,
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- [IEEE80211_RADIOTAP_RATE] = 0x11,
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- [IEEE80211_RADIOTAP_CHANNEL] = 0x24,
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- [IEEE80211_RADIOTAP_FHSS] = 0x22,
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- [IEEE80211_RADIOTAP_DBM_ANTSIGNAL] = 0x11,
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- [IEEE80211_RADIOTAP_DBM_ANTNOISE] = 0x11,
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- [IEEE80211_RADIOTAP_LOCK_QUALITY] = 0x22,
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- [IEEE80211_RADIOTAP_TX_ATTENUATION] = 0x22,
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- [IEEE80211_RADIOTAP_DB_TX_ATTENUATION] = 0x22,
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- [IEEE80211_RADIOTAP_DBM_TX_POWER] = 0x11,
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- [IEEE80211_RADIOTAP_ANTENNA] = 0x11,
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- [IEEE80211_RADIOTAP_DB_ANTSIGNAL] = 0x11,
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- [IEEE80211_RADIOTAP_DB_ANTNOISE] = 0x11,
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- [IEEE80211_RADIOTAP_RX_FLAGS] = 0x22,
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- [IEEE80211_RADIOTAP_TX_FLAGS] = 0x22,
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- [IEEE80211_RADIOTAP_RTS_RETRIES] = 0x11,
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- [IEEE80211_RADIOTAP_DATA_RETRIES] = 0x11,
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- /*
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- * add more here as they are defined in
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- * include/net/ieee80211_radiotap.h
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- */
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- };
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-
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- /*
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- * for every radiotap entry we can at
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- * least skip (by knowing the length)...
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- */
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-
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- while (iterator->arg_index < (int) sizeof(rt_sizes)) {
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- int hit = 0;
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- int pad;
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-
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- if (!(iterator->bitmap_shifter & 1))
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- goto next_entry; /* arg not present */
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-
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- /*
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- * arg is present, account for alignment padding
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- * 8-bit args can be at any alignment
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- * 16-bit args must start on 16-bit boundary
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- * 32-bit args must start on 32-bit boundary
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- * 64-bit args must start on 64-bit boundary
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- *
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- * note that total arg size can differ from alignment of
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- * elements inside arg, so we use upper nybble of length
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- * table to base alignment on
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- *
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- * also note: these alignments are ** relative to the
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- * start of the radiotap header **. There is no guarantee
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- * that the radiotap header itself is aligned on any
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- * kind of boundary.
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- *
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- * the above is why get_unaligned() is used to dereference
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- * multibyte elements from the radiotap area
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- */
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-
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- pad = (((ulong)iterator->arg) -
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- ((ulong)iterator->rtheader)) &
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- ((rt_sizes[iterator->arg_index] >> 4) - 1);
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-
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- if (pad)
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- iterator->arg +=
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- (rt_sizes[iterator->arg_index] >> 4) - pad;
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-
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- /*
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- * this is what we will return to user, but we need to
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- * move on first so next call has something fresh to test
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- */
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- iterator->this_arg_index = iterator->arg_index;
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- iterator->this_arg = iterator->arg;
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- hit = 1;
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-
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- /* internally move on the size of this arg */
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- iterator->arg += rt_sizes[iterator->arg_index] & 0x0f;
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-
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- /*
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- * check for insanity where we are given a bitmap that
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- * claims to have more arg content than the length of the
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- * radiotap section. We will normally end up equalling this
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- * max_length on the last arg, never exceeding it.
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- */
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-
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- if (((ulong)iterator->arg - (ulong)iterator->rtheader) >
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- (ulong) iterator->max_length)
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- return -EINVAL;
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-
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- next_entry:
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- iterator->arg_index++;
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- if (unlikely((iterator->arg_index & 31) == 0)) {
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- /* completed current u32 bitmap */
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- if (iterator->bitmap_shifter & 1) {
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- /* b31 was set, there is more */
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- /* move to next u32 bitmap */
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- iterator->bitmap_shifter = le32_to_cpu(
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- get_unaligned(iterator->next_bitmap));
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- iterator->next_bitmap++;
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- } else
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- /* no more bitmaps: end */
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- iterator->arg_index = sizeof(rt_sizes);
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- } else /* just try the next bit */
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- iterator->bitmap_shifter >>= 1;
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-
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- /* if we found a valid arg earlier, return it now */
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- if (hit)
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- return 0;
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- }
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-
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- /* we don't know how to handle any more args, we're done */
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- return -ENOENT;
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-}
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Jouni Malinen