src/utils/radiotap_iter.h

   1 #ifndef __RADIOTAP_ITER_H
   2 #define __RADIOTAP_ITER_H
   3
   4 #include <stdint.h>
   5 #include "radiotap.h"
   6
   7 /* Radiotap header iteration
   8  *   implemented in radiotap.c
   9  */
  10
  11 struct radiotap_override {
  12         uint8_t field;
  13         uint8_t align:4, size:4;
  14 };
  15
  16 struct radiotap_align_size {
  17         uint8_t align:4, size:4;
  18 };
  19
  20 struct ieee80211_radiotap_namespace {
  21         const struct radiotap_align_size *align_size;
  22         int n_bits;
  23         uint32_t oui;
  24         uint8_t subns;
  25 };
  26
  27 struct ieee80211_radiotap_vendor_namespaces {
  28         const struct ieee80211_radiotap_namespace *ns;
  29         int n_ns;
  30 };
  31
  32 /**
  33  * struct ieee80211_radiotap_iterator - tracks walk thru present radiotap args
  34  * @this_arg_index: index of current arg, valid after each successful call
  35  *      to ieee80211_radiotap_iterator_next()
  36  * @this_arg: pointer to current radiotap arg; it is valid after each
  37  *      call to ieee80211_radiotap_iterator_next() but also after
  38  *      ieee80211_radiotap_iterator_init() where it will point to
  39  *      the beginning of the actual data portion
  40  * @this_arg_size: length of the current arg, for convenience
  41  * @current_namespace: pointer to the current namespace definition
  42  *      (or internally %NULL if the current namespace is unknown)
  43  * @is_radiotap_ns: indicates whether the current namespace is the default
  44  *      radiotap namespace or not
  45  *
  46  * @overrides: override standard radiotap fields
  47  * @n_overrides: number of overrides
  48  *
  49  * @_rtheader: pointer to the radiotap header we are walking through
  50  * @_max_length: length of radiotap header in cpu byte ordering
  51  * @_arg_index: next argument index
  52  * @_arg: next argument pointer
  53  * @_next_bitmap: internal pointer to next present u32
  54  * @_bitmap_shifter: internal shifter for curr u32 bitmap, b0 set == arg present
  55  * @_vns: vendor namespace definitions
  56  * @_next_ns_data: beginning of the next namespace's data
  57  * @_reset_on_ext: internal; reset the arg index to 0 when going to the
  58  *      next bitmap word
  59  *
  60  * Describes the radiotap parser state. Fields prefixed with an underscore
  61  * must not be used by users of the parser, only by the parser internally.
  62  */
  63
  64 struct ieee80211_radiotap_iterator {
  65         struct ieee80211_radiotap_header *_rtheader;
  66         const struct ieee80211_radiotap_vendor_namespaces *_vns;
  67         const struct ieee80211_radiotap_namespace *current_namespace;
  68
  69         unsigned char *_arg, *_next_ns_data;
  70         le32 *_next_bitmap;
  71
  72         unsigned char *this_arg;
  73 #ifdef RADIOTAP_SUPPORT_OVERRIDES
  74         const struct radiotap_override *overrides;
  75         int n_overrides;
  76 #endif
  77         int this_arg_index;
  78         int this_arg_size;
  79
  80         int is_radiotap_ns;
  81
  82         int _max_length;
  83         int _arg_index;
  84         uint32_t _bitmap_shifter;
  85         int _reset_on_ext;
  86 };
  87
  88 extern int ieee80211_radiotap_iterator_init(
  89         struct ieee80211_radiotap_iterator *iterator,
  90         struct ieee80211_radiotap_header *radiotap_header,
  91         int max_length, const struct ieee80211_radiotap_vendor_namespaces *vns);
  92
  93 extern int ieee80211_radiotap_iterator_next(
  94         struct ieee80211_radiotap_iterator *iterator);
  95
  96 #endif /* __RADIOTAP_ITER_H */