/* * For DLT_PRISM_HEADER; like DLT_IEEE802_11, but with an extra header, * containing information such as radio information, which we * currently ignore. * * If, however, the packet begins with WLANCAP_MAGIC_COOKIE_V1 or * WLANCAP_MAGIC_COOKIE_V2, it's really DLT_IEEE802_11_RADIO_AVS * (currently, on Linux, there's no ARPHRD_ type for * DLT_IEEE802_11_RADIO_AVS, as there is a ARPHRD_IEEE80211_PRISM * for DLT_PRISM_HEADER, so ARPHRD_IEEE80211_PRISM is used for * the AVS header, and the first 4 bytes of the header are used to * indicate whether it's a Prism header or an AVS header). */ u_int prism_if_print(const struct pcap_pkthdr *h, const u_char *p) { u_int caplen = h->caplen; u_int length = h->len; u_int32_t msgcode; if (caplen < 4) { printf("[|802.11]"); return caplen; } msgcode = EXTRACT_32BITS(p); if (msgcode == WLANCAP_MAGIC_COOKIE_V1 || msgcode == WLANCAP_MAGIC_COOKIE_V2) return ieee802_11_avs_radio_print(p, length, caplen); if (caplen < PRISM_HDR_LEN) { printf("[|802.11]"); return caplen; } return PRISM_HDR_LEN + ieee802_11_print(p + PRISM_HDR_LEN, length - PRISM_HDR_LEN, caplen - PRISM_HDR_LEN, 0, 0); }
static u_int ieee802_11_avs_radio_print(const u_char *p, u_int length, u_int caplen) { u_int32_t caphdr_len; if (caplen < 8) { printf("[|802.11]"); return caplen; } caphdr_len = EXTRACT_32BITS(p + 4); if (caphdr_len < 8) { /* * Yow! The capture header length is claimed not * to be large enough to include even the version * cookie or capture header length! */ printf("[|802.11]"); return caplen; } if (caplen < caphdr_len) { printf("[|802.11]"); return caplen; } return caphdr_len + ieee802_11_print(p + caphdr_len, length - caphdr_len, caplen - caphdr_len, 0, 0); }
static u_int ieee802_11_radio_print(struct smartconfig *sc, const u_char * p, u_int length, u_int caplen) { #define BIT(n) (1U << n) #define IS_EXTENDED(__p) \ (EXTRACT_LE_32BITS(__p) & BIT(IEEE80211_RADIOTAP_EXT)) != 0 struct cpack_state cpacker; const struct ieee80211_radiotap_header *hdr; uint32_t presentflags; const uint32_t *presentp; u_int len; uint16_t channel = 0; uint8_t flags; if (caplen < sizeof(*hdr)) { return caplen; } hdr = (const struct ieee80211_radiotap_header *)p; len = EXTRACT_LE_16BITS(&hdr->it_len); if (caplen < len) { return caplen; } cpack_init(&cpacker, (const uint8_t *)hdr, len); /* align against header start */ cpack_advance(&cpacker, sizeof(*hdr)); /* includes the 1st bitmap */ flags = 0; presentp = &hdr->it_present; presentflags = EXTRACT_LE_32BITS(presentp); print_in_radiotap_namespace(sc, &cpacker, &flags, presentflags, 0, &channel); return len + ieee802_11_print(sc, p + len, length - len, caplen - len, channel); }
u_int ieee802_11_if_print(const struct pcap_pkthdr *h, const u_char *p) { return ieee802_11_print(p, h->len, h->caplen, 0); }
static u_int ieee802_11_radio_print(const u_char *p, u_int length, u_int caplen) { #define BITNO_32(x) (((x) >> 16) ? 16 + BITNO_16((x) >> 16) : BITNO_16((x))) #define BITNO_16(x) (((x) >> 8) ? 8 + BITNO_8((x) >> 8) : BITNO_8((x))) #define BITNO_8(x) (((x) >> 4) ? 4 + BITNO_4((x) >> 4) : BITNO_4((x))) #define BITNO_4(x) (((x) >> 2) ? 2 + BITNO_2((x) >> 2) : BITNO_2((x))) #define BITNO_2(x) (((x) & 2) ? 1 : 0) #define BIT(n) (1 << n) #define IS_EXTENDED(__p) \ (EXTRACT_LE_32BITS(__p) & BIT(IEEE80211_RADIOTAP_EXT)) != 0 struct cpack_state cpacker; struct ieee80211_radiotap_header *hdr; u_int32_t present, next_present; u_int32_t *presentp, *last_presentp; enum ieee80211_radiotap_type bit; int bit0; const u_char *iter; u_int len; int pad; if (caplen < sizeof(*hdr)) { printf("[|802.11]"); return caplen; } hdr = (struct ieee80211_radiotap_header *)p; len = EXTRACT_LE_16BITS(&hdr->it_len); if (caplen < len) { printf("[|802.11]"); return caplen; } for (last_presentp = &hdr->it_present; IS_EXTENDED(last_presentp) && (u_char*)(last_presentp + 1) <= p + len; last_presentp++); /* are there more bitmap extensions than bytes in header? */ if (IS_EXTENDED(last_presentp)) { printf("[|802.11]"); return caplen; } iter = (u_char*)(last_presentp + 1); if (cpack_init(&cpacker, (u_int8_t*)iter, len - (iter - p)) != 0) { /* XXX */ printf("[|802.11]"); return caplen; } /* Assume no Atheros padding between 802.11 header and body */ pad = 0; for (bit0 = 0, presentp = &hdr->it_present; presentp <= last_presentp; presentp++, bit0 += 32) { for (present = EXTRACT_LE_32BITS(presentp); present; present = next_present) { /* clear the least significant bit that is set */ next_present = present & (present - 1); /* extract the least significant bit that is set */ bit = (enum ieee80211_radiotap_type) (bit0 + BITNO_32(present ^ next_present)); if (print_radiotap_field(&cpacker, bit, &pad) != 0) goto out; } } out: return len + ieee802_11_print(p + len, length - len, caplen - len, pad); #undef BITNO_32 #undef BITNO_16 #undef BITNO_8 #undef BITNO_4 #undef BITNO_2 #undef BIT }