The branch main has been updated by adrian: URL: https://cgit.FreeBSD.org/src/commit/?id=93c6906e36a4e60e59279b6b6e18403ea23d56e1
commit 93c6906e36a4e60e59279b6b6e18403ea23d56e1 Author: EN-WEU WU <[email protected]> AuthorDate: 2026-06-16 14:54:05 +0000 Commit: Adrian Chadd <[email protected]> CommitDate: 2026-06-16 14:54:55 +0000 wtap(4): implement monitor mode and handle radiotap Implement monitor mode by simply adding IEEE80211_C_MONITOR to ic->ic_cap. To get additional informations when capturing 802.11 frames, radiotap is inserted by wtap_tx_tap() when TX and wtap_rx_tap() when RX. There are some type faults in struct wtap_rx_radiotap_header which are mainly mistakenly store unsigned values into signed integers. I have fixed them (wtap(4)) by complying with the types defined in https://www.radiotap.org/fields/defined. Becuase the struct wtap_rx_radiotap_header comes from ath(4), there may be another patch to fix the type faults in ath(4). Differential Review: https://reviews.freebsd.org/D36469 --- sys/dev/wtap/if_wtap.c | 59 ++++++++++++++++++++++++++++++++++++++++++--- sys/dev/wtap/if_wtapioctl.h | 31 ++++++++++++------------ 2 files changed, 71 insertions(+), 19 deletions(-) diff --git a/sys/dev/wtap/if_wtap.c b/sys/dev/wtap/if_wtap.c index d22b79a20dc4..d23036575d7a 100644 --- a/sys/dev/wtap/if_wtap.c +++ b/sys/dev/wtap/if_wtap.c @@ -229,6 +229,43 @@ wtap_beacon_config(struct wtap_softc *sc, struct ieee80211vap *vap) DWTAP_PRINTF("%s\n", __func__); } +static void +wtap_rx_tap(struct wtap_softc *sc, uint64_t tsf) +{ + struct ieee80211com *ic = &sc->sc_ic; + const struct ieee80211_rate_table *rt = ic->ic_rt; + struct wtap_rx_radiotap_header *rh = &sc->sc_rx_th; + + rh->wr_tsf = tsf; + rh->wr_flags = 0; + if (rt->rateCount) { + /* choose the fastest rate */ + rh->wr_rate = IEEE80211_RV(rt->info[rt->rateCount - 1].dot11Rate); + } + rh->wr_chan_flags = IEEE80211_CHAN_2GHZ; + rh->wr_chan_freq = ic->ic_curchan->ic_freq; + rh->wr_chan_ieee = ic->ic_curchan->ic_ieee; + rh->wr_chan_maxpow = 0; +} + +static void +wtap_tx_tap(struct wtap_softc *sc) +{ + struct ieee80211com *ic = &sc->sc_ic; + const struct ieee80211_rate_table *rt = ic->ic_rt; + struct wtap_tx_radiotap_header *th = &sc->sc_tx_th; + + th->wt_flags = 0; + if (rt->rateCount) { + /* choose the fastest rate */ + th->wt_rate = IEEE80211_RV(rt->info[rt->rateCount - 1].dot11Rate); + } + th->wt_chan_flags = IEEE80211_CHAN_2GHZ; + th->wt_chan_freq = ic->ic_curchan->ic_freq; + th->wt_chan_ieee = ic->ic_curchan->ic_ieee; + th->wt_chan_maxpow = 0; +} + static void wtap_beacon_intrp(void *arg) { @@ -261,8 +298,10 @@ wtap_beacon_intrp(void *arg) wh = mtod(m, struct ieee80211_frame *); memcpy(&wh[1], &tsf, sizeof(tsf)); - if (ieee80211_radiotap_active_vap(vap)) - ieee80211_radiotap_tx(vap, m); + if (ieee80211_radiotap_active_vap(vap)) { + wtap_tx_tap(sc); + ieee80211_radiotap_tx(vap, m); + } #if 0 medium_transmit(avp->av_md, avp->id, m); @@ -459,6 +498,8 @@ static int wtap_raw_xmit(struct ieee80211_node *ni, struct mbuf *m, const struct ieee80211_bpf_params *params) { + struct ieee80211com *ic = ni->ni_ic; + struct wtap_softc *sc = ic->ic_softc; #if 0 DWTAP_PRINTF("%s, %p\n", __func__, m); #endif @@ -466,6 +507,7 @@ wtap_raw_xmit(struct ieee80211_node *ni, struct mbuf *m, struct wtap_vap *avp = WTAP_VAP(vap); if (ieee80211_radiotap_active_vap(vap)) { + wtap_tx_tap(sc); ieee80211_radiotap_tx(vap, m); } if (m->m_flags & M_TXCB) @@ -529,6 +571,10 @@ wtap_rx_proc(void *arg, int npending) #if 0 ieee80211_dump_pkt(ic, mtod(m, caddr_t), 0,0,0); #endif + if (ieee80211_radiotap_active(ic)) { + uint64_t tsf = wtap_hal_get_tsf(sc->hal); + wtap_rx_tap(sc, tsf); + } /* * Use arbitrary but sane values, and do the correct conversion @@ -600,6 +646,7 @@ wtap_transmit(struct ieee80211com *ic, struct mbuf *m) struct ieee80211_node *ni = (struct ieee80211_node *) m->m_pkthdr.rcvif; struct ieee80211vap *vap = ni->ni_vap; + struct wtap_softc *sc = ic->ic_softc; struct wtap_vap *avp = WTAP_VAP(vap); struct ieee80211_key *k; struct ieee80211_frame *wh; @@ -612,8 +659,10 @@ wtap_transmit(struct ieee80211com *ic, struct mbuf *m) return (ENOBUFS); } - if (ieee80211_radiotap_active_vap(vap)) + if (ieee80211_radiotap_active_vap(vap)) { + wtap_tx_tap(sc); ieee80211_radiotap_tx(vap, m); + } if (m->m_flags & M_TXCB) ieee80211_process_callback(ni, m, 0); ieee80211_free_node(ni); @@ -668,7 +717,9 @@ wtap_attach(struct wtap_softc *sc, const uint8_t *macaddr) | IEEE80211_C_IBSS /* ibss, nee adhoc, mode */ | IEEE80211_C_STA /* station mode */ | IEEE80211_C_HOSTAP /* hostap mode */ - | IEEE80211_C_WPA; /* capable of WPA1+WPA2 */ + | IEEE80211_C_WPA /* capable of WPA1+WPA2 */ + | IEEE80211_C_MONITOR /* Enable monitor mode */ + ; ic->ic_cryptocaps = IEEE80211_CRYPTO_WEP diff --git a/sys/dev/wtap/if_wtapioctl.h b/sys/dev/wtap/if_wtapioctl.h index 05f88a5dcb81..f9fe35813576 100644 --- a/sys/dev/wtap/if_wtapioctl.h +++ b/sys/dev/wtap/if_wtapioctl.h @@ -139,41 +139,42 @@ struct wtap_stats { /* * Radio capture format. */ -#define WTAP_RX_RADIOTAP_PRESENT ( \ +#define WTAP_RX_RADIOTAP_PRESENT ( \ + (1 << IEEE80211_RADIOTAP_TSFT) | \ + (1 << IEEE80211_RADIOTAP_FLAGS) | \ + (1 << IEEE80211_RADIOTAP_RATE) | \ + (1 << IEEE80211_RADIOTAP_XCHANNEL) | \ 0) struct wtap_rx_radiotap_header { struct ieee80211_radiotap_header wr_ihdr; -#if 0 + u_int64_t wr_tsf; u_int8_t wr_flags; u_int8_t wr_rate; - int8_t wr_antsignal; - int8_t wr_antnoise; - u_int8_t wr_antenna; - u_int8_t wr_pad[3]; + u_int8_t wr_pad[2]; u_int32_t wr_chan_flags; u_int16_t wr_chan_freq; u_int8_t wr_chan_ieee; - int8_t wr_chan_maxpow; -#endif + u_int8_t wr_chan_maxpow; } __packed __aligned(8); -#define WTAP_TX_RADIOTAP_PRESENT ( \ +#define WTAP_TX_RADIOTAP_PRESENT ( \ + (1 << IEEE80211_RADIOTAP_FLAGS) | \ + (1 << IEEE80211_RADIOTAP_RATE) | \ + (1 << IEEE80211_RADIOTAP_XCHANNEL) | \ 0) struct wtap_tx_radiotap_header { struct ieee80211_radiotap_header wt_ihdr; -#if 0 + u_int8_t wt_flags; u_int8_t wt_rate; - u_int8_t wt_txpower; - u_int8_t wt_antenna; + u_int8_t wr_pad[2]; u_int32_t wt_chan_flags; u_int16_t wt_chan_freq; u_int8_t wt_chan_ieee; - int8_t wt_chan_maxpow; -#endif -} __packed; + u_int8_t wt_chan_maxpow; +} __packed __aligned(8); #endif
