Re: make tcpdump show 11n mode correctly
Anybody?
Did I write too much of a wall of text to explain the diff?
In that case, just read the diff. It should make sense.
On Sun, Dec 11, 2016 at 04:38:44PM +0100, Stefan Sperling wrote:
> This diff makes 'tcpdump -i iwn0 -y IEEE802_11_RADIO' show the
> correct mode for a channel in 11n mode.
> Before:
>
> After:
>
>
> Unfortunately this requires a kernel tweak because the kernel must
> be more careful about the channel flags it passes to userland.
>
> Channels exist in the 11b/g (2GHz) and 11a (5GHz) ranges.
> So net80211 has a "mode" concept, where a given mode is available
> if supported channels exist in a particular range. And there is the
> default "auto" mode which picks one of the other available modes.
> (This may not be the best design but it is how it was designed
> historically. Changing this is not in my radar.)
>
> The HT-channel flag is set to indicate whether a channel may be used
> in 11n mode. In practice this is just the superset of all channels
> supported by the device. When 11n support was introduced it was easier to
> fold the new 11n mode into the existing code with a flag like this, and
> avoid letting 11n mode be a special case which works against this design.
>
> And this HT-channel flag is set regardless of whether we're currently in
> 11n mode because we need this flag to enter 11n mode from another mode.
> A mode which has no channels available to it is not available.
> So the kernel needs this flag to be set on all channels at all times
> if the driver supports 11n.
>
> Now, we copy this flag out to userspace even in non-11n modes.
> If the kernel instead omits the HT-channel flag from the userspace copy if
> the current mode is not 11n, then tcpdump can inspect this flag to detect
> whether the channel is in fact an "11n" channel and print the mode correctly.
>
> In the end, this is just a cosmetic fix. If this is too much code
> churn and quirks for too little gain, I am happy to drop this diff.
>
> Index: sys/dev/pci/if_iwm.c
> ===
> RCS file: /cvs/src/sys/dev/pci/if_iwm.c,v
> retrieving revision 1.154
> diff -u -p -r1.154 if_iwm.c
> --- sys/dev/pci/if_iwm.c 10 Dec 2016 19:03:53 - 1.154
> +++ sys/dev/pci/if_iwm.c 11 Dec 2016 14:54:58 -
> @@ -3339,14 +3339,17 @@ iwm_rx_rx_mpdu(struct iwm_softc *sc, str
> if (sc->sc_drvbpf != NULL) {
> struct mbuf mb;
> struct iwm_rx_radiotap_header *tap = &sc->sc_rxtap;
> + uint16_t chan_flags;
>
> tap->wr_flags = 0;
> if (phy_info->phy_flags & htole16(IWM_PHY_INFO_FLAG_SHPREAMBLE))
> tap->wr_flags |= IEEE80211_RADIOTAP_F_SHORTPRE;
> tap->wr_chan_freq =
> htole16(ic->ic_channels[phy_info->channel].ic_freq);
> - tap->wr_chan_flags =
> - htole16(ic->ic_channels[phy_info->channel].ic_flags);
> + chan_flags = ic->ic_channels[phy_info->channel].ic_flags;
> + if (ic->ic_curmode != IEEE80211_MODE_11N)
> + chan_flags &= ~IEEE80211_CHAN_HT;
> + tap->wr_chan_flags = htole16(chan_flags);
> tap->wr_dbm_antsignal = (int8_t)rssi;
> tap->wr_dbm_antnoise = (int8_t)sc->sc_noise;
> tap->wr_tsft = phy_info->system_timestamp;
> @@ -3991,10 +3994,14 @@ iwm_tx(struct iwm_softc *sc, struct mbuf
> if (sc->sc_drvbpf != NULL) {
> struct mbuf mb;
> struct iwm_tx_radiotap_header *tap = &sc->sc_txtap;
> + uint16_t chan_flags;
>
> tap->wt_flags = 0;
> tap->wt_chan_freq = htole16(ni->ni_chan->ic_freq);
> - tap->wt_chan_flags = htole16(ni->ni_chan->ic_flags);
> + chan_flags = ni->ni_chan->ic_flags;
> + if (ic->ic_curmode != IEEE80211_MODE_11N)
> + chan_flags &= ~IEEE80211_CHAN_HT;
> + tap->wt_chan_flags = htole16(chan_flags);
> if ((ni->ni_flags & IEEE80211_NODE_HT) &&
> !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
> type == IEEE80211_FC0_TYPE_DATA &&
> Index: sys/dev/pci/if_iwn.c
> ===
> RCS file: /cvs/src/sys/dev/pci/if_iwn.c,v
> retrieving revision 1.178
> diff -u -p -r1.178 if_iwn.c
> --- sys/dev/pci/if_iwn.c 10 Dec 2016 13:22:07 - 1.178
> +++ sys/dev/pci/if_iwn.c 11 Dec 2016 14:54:25 -
> @@ -2130,14 +2130,17 @@ iwn_rx_done(struct iwn_softc *sc, struct
> if (sc->sc_drvbpf != NULL) {
> struct mbuf mb;
> struct iwn_rx_radiotap_header *tap = &sc->sc_rxtap;
> + uint16_t chan_flags;
>
> tap->wr_flags = 0;
> if (stat->flags & htole16(IWN_STAT_FLAG_SHPREAMBLE))
> tap->wr_flags |= IEEE80211_RADIOTAP_F_SHORTPRE;
> tap->wr_chan_freq =
>
Re: kernel diagnostic assertion "ifa == rt->rt_ifa", rt_ifa_addlocal
On 17/12/16(Sat) 07:52, Stefan Sperling wrote: > On Sat, Dec 17, 2016 at 02:33:37AM +0100, Alexander Bluhm wrote: > > Hi, > > > > If rt_ifa_addlocal() in in_ifinit() fails, the address has been > > added to the interface address list, but the local route is missing. > > This inconsistency can result in a panic later. > > > > panic: kernel diagnostic assertion "ifa == rt->rt_ifa" failed: file > > "/crypt/home/bluhm/openbsd/cvs/src/sys/netinet/if_ether.c", line 206 > > > > I have seen this crash in production on a 5.9 system and could > > reproduce it on -current by inducing an error in rt_ifa_addlocal(). > > > > So in case of an error, remove the interface address to get a > > consistent state again. > > > > ok? Haha, I have a similar diff in my tree! I couldn't find a way to make rt_ifa_addlocal() fail, but I agree this is needed. ok mpi@ > The little dance with an aditional error variable is a bit confusing. > It would be nice to avoid the extra variable. But off-hand I could not > find a simpler diff which keeps the semantics of re-adding the original > address if the ioctl errors. So your approach seems fine. The proper way to simplify this mess is to always call in_ifinit() with newifaddr = 1. But it is the kind of work nobody want to spend her time on.
Re: BFD: route get and route monitor
On 2016 Sep 30 (Fri) at 10:16:19 +0200 (+0200), Peter Hessler wrote:
:This diff makes route get and route monitor work. sockaddr_bfd is so we
:can play like the other RTAX_* indexes in rti_info of route messages.
:
:OK?
Updated output, requested by Theo. A normal get will show just the bfd
state, use "-bfd" to get all of the information.
OK?
$ route -n get 203.0.113.9
route to: 203.0.113.9
destination: 203.0.113.9
mask: 255.255.255.255
interface: em1
if address: 203.0.113.1
priority: 4 (connected)
flags:
BFD: async state up remote up
use mtuexpire
83924 0 133
sockaddrs:
$ route -n get 203.0.113.9 -bfd
route to: 203.0.113.9
destination: 203.0.113.9
mask: 255.255.255.255
interface: em1
if address: 203.0.113.1
priority: 4 (connected)
flags:
BFD: async state up remote up laststate down error 0
diag none remote neighbor-down
discr 186919089 remote 55
uptime 05d 2h07m29s
mintx 100 minrx 100 minecho 0 multiplier 3
use mtuexpire
83923 0 229
sockaddrs:
Index: sbin/route/Makefile
===
RCS file: /cvs/openbsd/src/sbin/route/Makefile,v
retrieving revision 1.13
diff -u -p -u -p -r1.13 Makefile
--- sbin/route/Makefile 19 Jul 2013 14:41:46 - 1.13
+++ sbin/route/Makefile 17 Dec 2016 12:47:35 -
@@ -4,7 +4,7 @@ PROG= route
MAN= route.8
SRCS= route.c show.c
-CFLAGS+= -Wall
+CFLAGS+= -Wall -DBFD
route.o .depend lint tags: keywords.h
Index: sbin/route/route.c
===
RCS file: /cvs/openbsd/src/sbin/route/route.c,v
retrieving revision 1.193
diff -u -p -u -p -r1.193 route.c
--- sbin/route/route.c 13 Dec 2016 08:40:54 - 1.193
+++ sbin/route/route.c 17 Dec 2016 12:47:35 -
@@ -100,6 +100,7 @@ const char *bfd_state(unsigned int);
const char *bfd_diag(unsigned int);
const char *bfd_calc_uptime(time_t);
voidprint_bfdmsg(struct rt_msghdr *);
+voidprint_sabfd(struct sockaddr_bfd *, int);
#endif
const char *get_linkstate(int, int);
voidprint_rtmsg(struct rt_msghdr *, int);
@@ -1443,6 +1444,9 @@ print_getmsg(struct rt_msghdr *rtm, int
struct sockaddr *dst = NULL, *gate = NULL, *mask = NULL, *ifa = NULL;
struct sockaddr_dl *ifp = NULL;
struct sockaddr_rtlabel *sa_rl = NULL;
+#ifdef BFD
+ struct sockaddr_bfd *sa_bfd = NULL;
+#endif
struct sockaddr *mpls = NULL;
struct sockaddr *sa;
char *cp;
@@ -1491,6 +1495,11 @@ print_getmsg(struct rt_msghdr *rtm, int
case RTA_LABEL:
sa_rl = (struct sockaddr_rtlabel *)sa;
break;
+#ifdef BFD
+ case RTA_BFD:
+ sa_bfd = (struct sockaddr_bfd *)sa;
+ break;
+#endif
}
ADVANCE(cp, sa);
}
@@ -1523,6 +1532,10 @@ print_getmsg(struct rt_msghdr *rtm, int
printf("\n");
if (sa_rl != NULL)
printf(" label: %s\n", sa_rl->sr_label);
+#ifdef BFD
+ if (sa_bfd)
+ print_sabfd(sa_bfd, rtm->rtm_fmask);
+#endif
#define lock(f)((rtm->rtm_rmx.rmx_locks & __CONCAT(RTV_,f)) ? 'L' : '
')
relative_expire = rtm->rtm_rmx.rmx_expire ?
@@ -1625,12 +1638,21 @@ void
print_bfdmsg(struct rt_msghdr *rtm)
{
struct bfd_msghdr *bfdm = (struct bfd_msghdr *)rtm;
+
+ printf("\n");
+ print_sabfd(&bfdm->bm_sa, rtm->rtm_fmask);
+ pmsg_addrs(((char *)rtm + rtm->rtm_hdrlen), rtm->rtm_addrs);
+}
+
+void
+print_sabfd(struct sockaddr_bfd *sa_bfd, int fmask)
+{
struct timeval tv;
gettimeofday(&tv, NULL);
- printf(" mode ");
- switch (bfdm->bm_mode) {
+ printf("BFD: ");
+ switch (sa_bfd->bs_mode) {
case BFD_MODE_ASYNC:
printf("async");
break;
@@ -1638,27 +1660,36 @@ print_bfdmsg(struct rt_msghdr *rtm)
printf("demand");
break;
default:
- printf("unknown %u", bfdm->bm_mode);
+ printf("unknown %u", sa_bfd->bs_mode);
break;
}
- printf(" state %s", bfd_state(bfdm->bm_state));
- printf(" remotestate %s", bfd_state(bfdm->bm_remotestate));
- printf(" laststate %s", bfd_state(bfdm->bm_laststate));
-
- printf(" error %d", bfdm->bm_error);
- printf(" localdiscr %u", bfdm->bm_localdiscr);
- printf(" remotediscr %u", bfdm->bm_remotediscr);
- printf(" localdiag %s", bfd_diag(bfdm->bm_localdiag));
- printf(" remotediag %s", bfd_diag(bfdm->bm_remotediag));
- printf(" uptime %s", bfd_calc_uptime(tv.t
