diff options
| -rw-r--r-- | epan/dissectors/packet-radiotap.c | 25 |
1 files changed, 14 insertions, 11 deletions
diff --git a/epan/dissectors/packet-radiotap.c b/epan/dissectors/packet-radiotap.c index c1c02049f2..673d12eee6 100644 --- a/epan/dissectors/packet-radiotap.c +++ b/epan/dissectors/packet-radiotap.c @@ -65,6 +65,11 @@ struct ieee80211_radiotap_header { */ }; +#define RADIOTAP_MIN_HEADER_LEN 8 /* minimum header length */ +#define RADIOTAP_VERSION_OFFSET 0 /* offset of version field */ +#define RADIOTAP_LENGTH_OFFSET 2 /* offset of length field */ +#define RADIOTAP_PRESENT_OFFSET 4 /* offset of "present" field */ + enum ieee80211_radiotap_type { IEEE80211_RADIOTAP_TSFT = 0, IEEE80211_RADIOTAP_FLAGS = 1, @@ -230,17 +235,15 @@ dissect_radiotap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree); void capture_radiotap(const guchar *pd, int offset, int len, packet_counts *ld) { - const struct ieee80211_radiotap_header *hdr; guint16 it_len; guint32 present; guint8 rflags; - if(!BYTES_ARE_IN_FRAME(offset, len, (int)sizeof(*hdr))) { + if(!BYTES_ARE_IN_FRAME(offset, len, RADIOTAP_MIN_HEADER_LEN)) { ld->other ++; return; } - hdr = (const struct ieee80211_radiotap_header *)&pd[offset]; - it_len = pletohs(&hdr->it_len); + it_len = pletohs(&pd[RADIOTAP_LENGTH_OFFSET]); if(!BYTES_ARE_IN_FRAME(offset, len, it_len)) { ld->other ++; return; @@ -252,15 +255,15 @@ capture_radiotap(const guchar *pd, int offset, int len, packet_counts *ld) return; } - if(it_len < sizeof(*hdr)) { + if(it_len < RADIOTAP_MIN_HEADER_LEN) { /* Header length is shorter than fixed-length portion of header */ ld->other ++; return; } - present = pletohl(&hdr->it_present); - offset += sizeof(*hdr); - it_len -= sizeof(*hdr); + present = pletohl(&pd[RADIOTAP_PRESENT_OFFSET]); + offset += RADIOTAP_MIN_HEADER_LEN; + it_len -= RADIOTAP_MIN_HEADER_LEN; rflags = 0; @@ -671,7 +674,7 @@ dissect_radiotap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) * FIXME: This only works if there is exactly 1 it_present * field in the header */ - if (length_remaining < sizeof(struct ieee80211_radiotap_header)) { + if (length_remaining < RADIOTAP_MIN_HEADER_LEN) { /* * Radiotap header is shorter than the fixed-length portion * plus one "present" bitset. @@ -719,8 +722,8 @@ dissect_radiotap(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) proto_tree_add_item(present_tree, hf_radiotap_present_ext, tvb, 4, 4, TRUE); } - offset += sizeof(struct ieee80211_radiotap_header); - length_remaining -= sizeof(struct ieee80211_radiotap_header); + offset += RADIOTAP_MIN_HEADER_LEN; + length_remaining -= RADIOTAP_MIN_HEADER_LEN; rflags = 0; for (; present; present = next_present) { |