diff options
| -rw-r--r-- | include/net/cfg80211.h | 83 | ||||
| -rw-r--r-- | include/net/ieee80211_radiotap.h | 4 | ||||
| -rw-r--r-- | net/mac80211/tx.c | 9 | ||||
| -rw-r--r-- | net/wireless/radiotap.c | 305 |
4 files changed, 271 insertions, 130 deletions
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index a3f0a7e..5b3569b 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1561,37 +1561,82 @@ ieee80211_get_response_rate(struct ieee80211_supported_band *sband, * Documentation in Documentation/networking/radiotap-headers.txt */ +struct radiotap_align_size { + uint8_t align:4, size:4; +}; + +struct ieee80211_radiotap_namespace { + const struct radiotap_align_size *align_size; + int n_bits; + uint32_t oui; + uint8_t subns; +}; + +struct ieee80211_radiotap_vendor_namespaces { + const struct ieee80211_radiotap_namespace *ns; + int n_ns; +}; + /** * struct ieee80211_radiotap_iterator - tracks walk thru present radiotap args - * @rtheader: pointer to the radiotap header we are walking through - * @max_length: length of radiotap header in cpu byte ordering - * @this_arg_index: IEEE80211_RADIOTAP_... index of current arg - * @this_arg: pointer to current radiotap arg - * @arg_index: internal next argument index - * @arg: internal next argument pointer - * @next_bitmap: internal pointer to next present u32 - * @bitmap_shifter: internal shifter for curr u32 bitmap, b0 set == arg present + * @this_arg_index: index of current arg, valid after each successful call + * to ieee80211_radiotap_iterator_next() + * @this_arg: pointer to current radiotap arg; it is valid after each + * call to ieee80211_radiotap_iterator_next() but also after + * ieee80211_radiotap_iterator_init() where it will point to + * the beginning of the actual data portion + * @this_arg_size: length of the current arg, for convenience + * @current_namespace: pointer to the current namespace definition + * (or internally %NULL if the current namespace is unknown) + * @is_radiotap_ns: indicates whether the current namespace is the default + * radiotap namespace or not + * + * @overrides: override standard radiotap fields + * @n_overrides: number of overrides + * + * @_rtheader: pointer to the radiotap header we are walking through + * @_max_length: length of radiotap header in cpu byte ordering + * @_arg_index: next argument index + * @_arg: next argument pointer + * @_next_bitmap: internal pointer to next present u32 + * @_bitmap_shifter: internal shifter for curr u32 bitmap, b0 set == arg present + * @_vns: vendor namespace definitions + * @_next_ns_data: beginning of the next namespace's data + * @_reset_on_ext: internal; reset the arg index to 0 when going to the + * next bitmap word + * + * Describes the radiotap parser state. Fields prefixed with an underscore + * must not be used by users of the parser, only by the parser internally. */ struct ieee80211_radiotap_iterator { - struct ieee80211_radiotap_header *rtheader; - int max_length; + struct ieee80211_radiotap_header *_rtheader; + const struct ieee80211_radiotap_vendor_namespaces *_vns; + const struct ieee80211_radiotap_namespace *current_namespace; + + unsigned char *_arg, *_next_ns_data; + uint32_t *_next_bitmap; + + unsigned char *this_arg; int this_arg_index; - u8 *this_arg; + int this_arg_size; - int arg_index; - u8 *arg; - __le32 *next_bitmap; - u32 bitmap_shifter; + int is_radiotap_ns; + + int _max_length; + int _arg_index; + uint32_t _bitmap_shifter; + int _reset_on_ext; }; extern int ieee80211_radiotap_iterator_init( - struct ieee80211_radiotap_iterator *iterator, - struct ieee80211_radiotap_header *radiotap_header, - int max_length); + struct ieee80211_radiotap_iterator *iterator, + struct ieee80211_radiotap_header *radiotap_header, + int max_length, const struct ieee80211_radiotap_vendor_namespaces *vns); extern int ieee80211_radiotap_iterator_next( - struct ieee80211_radiotap_iterator *iterator); + struct ieee80211_radiotap_iterator *iterator); + extern const unsigned char rfc1042_header[6]; extern const unsigned char bridge_tunnel_header[6]; diff --git a/include/net/ieee80211_radiotap.h b/include/net/ieee80211_radiotap.h index 9d3d86a..af49f8a 100644 --- a/include/net/ieee80211_radiotap.h +++ b/include/net/ieee80211_radiotap.h @@ -198,6 +198,10 @@ enum ieee80211_radiotap_type { IEEE80211_RADIOTAP_TX_FLAGS = 15, IEEE80211_RADIOTAP_RTS_RETRIES = 16, IEEE80211_RADIOTAP_DATA_RETRIES = 17, + + /* valid in every it_present bitmap, even vendor namespaces */ + IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE = 29, + IEEE80211_RADIOTAP_VENDOR_NAMESPACE = 30, IEEE80211_RADIOTAP_EXT = 31 }; diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 85e382a..e392820 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1010,7 +1010,8 @@ static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx, (struct ieee80211_radiotap_header *) skb->data; struct ieee80211_supported_band *sband; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); - int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len); + int ret = ieee80211_radiotap_iterator_init(&iterator, rthdr, skb->len, + NULL); sband = tx->local->hw.wiphy->bands[tx->channel->band]; @@ -1046,7 +1047,7 @@ static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx, * because it will be recomputed and added * on transmission */ - if (skb->len < (iterator.max_length + FCS_LEN)) + if (skb->len < (iterator._max_length + FCS_LEN)) return false; skb_trim(skb, skb->len - FCS_LEN); @@ -1073,10 +1074,10 @@ static bool __ieee80211_parse_tx_radiotap(struct ieee80211_tx_data *tx, /* * remove the radiotap header - * iterator->max_length was sanity-checked against + * iterator->_max_length was sanity-checked against * skb->len by iterator init */ - skb_pull(skb, iterator.max_length); + skb_pull(skb, iterator._max_length); return true; } diff --git a/net/wireless/radiotap.c b/net/wireless/radiotap.c index f591871..1332c44 100644 --- a/net/wireless/radiotap.c +++ b/net/wireless/radiotap.c @@ -2,6 +2,16 @@ * Radiotap parser * * Copyright 2007 Andy Green <andy@warmcat.com> + * Copyright 2009 Johannes Berg <johannes@sipsolutions.net> + * + * 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 COPYING for more details. */ #include <net/cfg80211.h> @@ -10,6 +20,35 @@ /* function prototypes and related defs are in include/net/cfg80211.h */ +static const struct radiotap_align_size rtap_namespace_sizes[] = { + [IEEE80211_RADIOTAP_TSFT] = { .align = 8, .size = 8, }, + [IEEE80211_RADIOTAP_FLAGS] = { .align = 1, .size = 1, }, + [IEEE80211_RADIOTAP_RATE] = { .align = 1, .size = 1, }, + [IEEE80211_RADIOTAP_CHANNEL] = { .align = 2, .size = 4, }, + [IEEE80211_RADIOTAP_FHSS] = { .align = 2, .size = 2, }, + [IEEE80211_RADIOTAP_DBM_ANTSIGNAL] = { .align = 1, .size = 1, }, + [IEEE80211_RADIOTAP_DBM_ANTNOISE] = { .align = 1, .size = 1, }, + [IEEE80211_RADIOTAP_LOCK_QUALITY] = { .align = 2, .size = 2, }, + [IEEE80211_RADIOTAP_TX_ATTENUATION] = { .align = 2, .size = 2, }, + [IEEE80211_RADIOTAP_DB_TX_ATTENUATION] = { .align = 2, .size = 2, }, + [IEEE80211_RADIOTAP_DBM_TX_POWER] = { .align = 1, .size = 1, }, + [IEEE80211_RADIOTAP_ANTENNA] = { .align = 1, .size = 1, }, + [IEEE80211_RADIOTAP_DB_ANTSIGNAL] = { .align = 1, .size = 1, }, + [IEEE80211_RADIOTAP_DB_ANTNOISE] = { .align = 1, .size = 1, }, + [IEEE80211_RADIOTAP_RX_FLAGS] = { .align = 2, .size = 2, }, + [IEEE80211_RADIOTAP_TX_FLAGS] = { .align = 2, .size = 2, }, + [IEEE80211_RADIOTAP_RTS_RETRIES] = { .align = 1, .size = 1, }, + [IEEE80211_RADIOTAP_DATA_RETRIES] = { .align = 1, .size = 1, }, + /* + * add more here as they are defined in radiotap.h + */ +}; + +static const struct ieee80211_radiotap_namespace radiotap_ns = { + .n_bits = sizeof(rtap_namespace_sizes) / sizeof(rtap_namespace_sizes[0]), + .align_size = rtap_namespace_sizes, +}; + /** * ieee80211_radiotap_iterator_init - radiotap parser iterator initialization * @iterator: radiotap_iterator to initialize @@ -50,9 +89,9 @@ */ int ieee80211_radiotap_iterator_init( - struct ieee80211_radiotap_iterator *iterator, - struct ieee80211_radiotap_header *radiotap_header, - int max_length) + struct ieee80211_radiotap_iterator *iterator, + struct ieee80211_radiotap_header *radiotap_header, + int max_length, const struct ieee80211_radiotap_vendor_namespaces *vns) { /* Linux only supports version 0 radiotap format */ if (radiotap_header->it_version) @@ -62,19 +101,24 @@ int ieee80211_radiotap_iterator_init( if (max_length < get_unaligned_le16(&radiotap_header->it_len)) return -EINVAL; - iterator->rtheader = radiotap_header; - iterator->max_length = get_unaligned_le16(&radiotap_header->it_len); - iterator->arg_index = 0; - iterator->bitmap_shifter = get_unaligned_le32(&radiotap_header->it_present); - iterator->arg = (u8 *)radiotap_header + sizeof(*radiotap_header); - iterator->this_arg = NULL; + iterator->_rtheader = radiotap_header; + iterator->_max_length = get_unaligned_le16(&radiotap_header->it_len); + iterator->_arg_index = 0; + iterator->_bitmap_shifter = get_unaligned_le32(&radiotap_header->it_present); + iterator->_arg = (uint8_t *)radiotap_header + sizeof(*radiotap_header); + iterator->_reset_on_ext = 0; + iterator->_next_bitmap = &radiotap_header->it_present; + iterator->_next_bitmap++; + iterator->_vns = vns; + iterator->current_namespace = &radiotap_ns; + iterator->is_radiotap_ns = 1; /* find payload start allowing for extended bitmap(s) */ - if (unlikely(iterator->bitmap_shifter & (1<<IEEE80211_RADIOTAP_EXT))) { - while (get_unaligned_le32(iterator->arg) & - (1 << IEEE80211_RADIOTAP_EXT)) { - iterator->arg += sizeof(u32); + if (iterator->_bitmap_shifter & (1<<IEEE80211_RADIOTAP_EXT)) { + while (get_unaligned_le32(iterator->_arg) & + (1 << IEEE80211_RADIOTAP_EXT)) { + iterator->_arg += sizeof(uint32_t); /* * check for insanity where the present bitmaps @@ -82,12 +126,13 @@ int ieee80211_radiotap_iterator_init( * stated radiotap header length */ - if (((ulong)iterator->arg - - (ulong)iterator->rtheader) > iterator->max_length) + if ((unsigned long)iterator->_arg - + (unsigned long)iterator->_rtheader > + (unsigned long)iterator->_max_length) return -EINVAL; } - iterator->arg += sizeof(u32); + iterator->_arg += sizeof(uint32_t); /* * no need to check again for blowing past stated radiotap @@ -96,12 +141,36 @@ int ieee80211_radiotap_iterator_init( */ } + iterator->this_arg = iterator->_arg; + /* we are all initialized happily */ return 0; } EXPORT_SYMBOL(ieee80211_radiotap_iterator_init); +static void find_ns(struct ieee80211_radiotap_iterator *iterator, + uint32_t oui, uint8_t subns) +{ + int i; + + iterator->current_namespace = NULL; + + if (!iterator->_vns) + return; + + for (i = 0; i < iterator->_vns->n_ns; i++) { + if (iterator->_vns->ns[i].oui != oui) + continue; + if (iterator->_vns->ns[i].subns != subns) + continue; + + iterator->current_namespace = &iterator->_vns->ns[i]; + break; + } +} + + /** * ieee80211_radiotap_iterator_next - return next radiotap parser iterator arg @@ -127,99 +196,80 @@ EXPORT_SYMBOL(ieee80211_radiotap_iterator_init); */ int ieee80211_radiotap_iterator_next( - struct ieee80211_radiotap_iterator *iterator) + 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 < sizeof(rt_sizes)) { + while (1) { int hit = 0; - int pad; + int pad, align, size, subns, vnslen; + uint32_t oui; - if (!(iterator->bitmap_shifter & 1)) + /* if no more EXT bits, that's it */ + if ((iterator->_arg_index % 32) == IEEE80211_RADIOTAP_EXT && + !(iterator->_bitmap_shifter & 1)) + return -ENOENT; + + if (!(iterator->_bitmap_shifter & 1)) goto next_entry; /* arg not present */ + /* get alignment/size of data */ + switch (iterator->_arg_index % 32) { + case IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE: + case IEEE80211_RADIOTAP_EXT: + align = 1; + size = 0; + break; + case IEEE80211_RADIOTAP_VENDOR_NAMESPACE: + align = 2; + size = 6; + break; + default: + if (!iterator->current_namespace || + iterator->_arg_index >= iterator->current_namespace->n_bits) { + if (iterator->current_namespace == &radiotap_ns) + return -ENOENT; + align = 0; + } else { + align = iterator->current_namespace->align_size[iterator->_arg_index].align; + size = iterator->current_namespace->align_size[iterator->_arg_index].size; + } + if (!align) { + /* skip all subsequent data */ + iterator->_arg = iterator->_next_ns_data; + /* give up on this namespace */ + iterator->current_namespace = NULL; + goto next_entry; + } + break; + } + /* * 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 + * Note that 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 + * 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); + pad = ((unsigned long)iterator->_arg - + (unsigned long)iterator->_rtheader) & (align - 1); if (pad) - iterator->arg += - (rt_sizes[iterator->arg_index] >> 4) - pad; + iterator->_arg += align - 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; + iterator->this_arg_index = iterator->_arg_index; + iterator->this_arg = iterator->_arg; + iterator->this_arg_size = size; /* internally move on the size of this arg */ - iterator->arg += rt_sizes[iterator->arg_index] & 0x0f; + iterator->_arg += size; /* * check for insanity where we are given a bitmap that @@ -228,32 +278,73 @@ int ieee80211_radiotap_iterator_next( * max_length on the last arg, never exceeding it. */ - if (((ulong)iterator->arg - (ulong)iterator->rtheader) > - iterator->max_length) + if ((unsigned long)iterator->_arg - + (unsigned long)iterator->_rtheader > + (unsigned long)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 = - get_unaligned_le32(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; + /* these special ones are valid in each bitmap word */ + switch (iterator->_arg_index % 32) { + case IEEE80211_RADIOTAP_VENDOR_NAMESPACE: + iterator->_bitmap_shifter >>= 1; + iterator->_arg_index++; + + iterator->_reset_on_ext = 1; + + vnslen = get_unaligned_le16(iterator->this_arg + 4); + iterator->_next_ns_data = iterator->_arg + vnslen; + oui = (*iterator->this_arg << 16) | + (*(iterator->this_arg + 1) << 8) | + *(iterator->this_arg + 2); + subns = *(iterator->this_arg + 3); + + find_ns(iterator, oui, subns); + + iterator->is_radiotap_ns = 0; + /* allow parsers to show this information */ + iterator->this_arg_index = + IEEE80211_RADIOTAP_VENDOR_NAMESPACE; + iterator->this_arg_size += vnslen; + if ((unsigned long)iterator->this_arg + + iterator->this_arg_size - + (unsigned long)iterator->_rtheader > + (unsigned long)(unsigned long)iterator->_max_length) + return -EINVAL; + hit = 1; + break; + case IEEE80211_RADIOTAP_RADIOTAP_NAMESPACE: + iterator->_bitmap_shifter >>= 1; + iterator->_arg_index++; + + iterator->_reset_on_ext = 1; + iterator->current_namespace = &radiotap_ns; + iterator->is_radiotap_ns = 1; + break; + case IEEE80211_RADIOTAP_EXT: + /* + * bit 31 was set, there is more + * -- move to next u32 bitmap + */ + iterator->_bitmap_shifter = + get_unaligned_le32(iterator->_next_bitmap); + iterator->_next_bitmap++; + if (iterator->_reset_on_ext) + iterator->_arg_index = 0; + else + iterator->_arg_index++; + iterator->_reset_on_ext = 0; + break; + default: + /* we've got a hit! */ + hit = 1; + next_entry: + iterator->_bitmap_shifter >>= 1; + iterator->_arg_index++; + } /* 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; } EXPORT_SYMBOL(ieee80211_radiotap_iterator_next); |