On Tue, Jan 31, 2023 at 12:36:38AM +0900, Akihiko Odaki wrote: > On 2023/01/31 0:12, Michael S. Tsirkin wrote: > > On Mon, Jan 30, 2023 at 10:47:07PM +0900, Akihiko Odaki wrote: > > > filter-dump specifiees Ethernet as PCAP LinkType, which does not expect > > > virtio-net header. Having virtio-net header in such PCAP file breaks > > > PCAP unconsumable. Unfortunately currently there is no LinkType for > > > virtio-net so for now strip virtio-net header to convert the output to > > > Ethernet. > > > > > > Signed-off-by: Akihiko Odaki <akihiko.od...@daynix.com> > > > > Probably means you need to calculate checksums and split gso too right? > > It was not necessary in my case as I used Wireshark and it tolerates wrong > checksums and large packets (it even says "Checksum incorrect [maybe caused > by 'TCP checksum offload'?]"). It was even more helpful to have raw packets > instead of transformed packets for debugging purposes. Perhaps an option to > transform packets may be added later if a need arises.
I think we should add LINKTYPE_VIRTIO. Very useful to debug a host of checksum/segmentation issues. Want to hack it up? > > > > > --- > > > include/net/net.h | 6 ++++++ > > > net/dump.c | 11 +++++++---- > > > net/net.c | 18 ++++++++++++++++++ > > > net/tap.c | 16 ++++++++++++++++ > > > 4 files changed, 47 insertions(+), 4 deletions(-) > > > > > > diff --git a/include/net/net.h b/include/net/net.h > > > index dc20b31e9f..4b2d72b3fc 100644 > > > --- a/include/net/net.h > > > +++ b/include/net/net.h > > > @@ -56,8 +56,10 @@ typedef RxFilterInfo *(QueryRxFilter)(NetClientState > > > *); > > > typedef bool (HasUfo)(NetClientState *); > > > typedef bool (HasVnetHdr)(NetClientState *); > > > typedef bool (HasVnetHdrLen)(NetClientState *, int); > > > +typedef bool (GetUsingVnetHdr)(NetClientState *); > > > typedef void (UsingVnetHdr)(NetClientState *, bool); > > > typedef void (SetOffload)(NetClientState *, int, int, int, int, int); > > > +typedef int (GetVnetHdrLen)(NetClientState *); > > > typedef void (SetVnetHdrLen)(NetClientState *, int); > > > typedef int (SetVnetLE)(NetClientState *, bool); > > > typedef int (SetVnetBE)(NetClientState *, bool); > > > @@ -84,8 +86,10 @@ typedef struct NetClientInfo { > > > HasUfo *has_ufo; > > > HasVnetHdr *has_vnet_hdr; > > > HasVnetHdrLen *has_vnet_hdr_len; > > > + GetUsingVnetHdr *get_using_vnet_hdr; > > > UsingVnetHdr *using_vnet_hdr; > > > SetOffload *set_offload; > > > + GetVnetHdrLen *get_vnet_hdr_len; > > > SetVnetHdrLen *set_vnet_hdr_len; > > > SetVnetLE *set_vnet_le; > > > SetVnetBE *set_vnet_be; > > > @@ -183,9 +187,11 @@ void qemu_format_nic_info_str(NetClientState *nc, > > > uint8_t macaddr[6]); > > > bool qemu_has_ufo(NetClientState *nc); > > > bool qemu_has_vnet_hdr(NetClientState *nc); > > > bool qemu_has_vnet_hdr_len(NetClientState *nc, int len); > > > +bool qemu_get_using_vnet_hdr(NetClientState *nc); > > > void qemu_using_vnet_hdr(NetClientState *nc, bool enable); > > > void qemu_set_offload(NetClientState *nc, int csum, int tso4, int tso6, > > > int ecn, int ufo); > > > +int qemu_get_vnet_hdr_len(NetClientState *nc); > > > void qemu_set_vnet_hdr_len(NetClientState *nc, int len); > > > int qemu_set_vnet_le(NetClientState *nc, bool is_le); > > > int qemu_set_vnet_be(NetClientState *nc, bool is_be); > > > diff --git a/net/dump.c b/net/dump.c > > > index 6a63b15359..7d05f16ca7 100644 > > > --- a/net/dump.c > > > +++ b/net/dump.c > > > @@ -61,12 +61,13 @@ struct pcap_sf_pkthdr { > > > uint32_t len; > > > }; > > > -static ssize_t dump_receive_iov(DumpState *s, const struct iovec *iov, > > > int cnt) > > > +static ssize_t dump_receive_iov(DumpState *s, const struct iovec *iov, > > > int cnt, > > > + int offset) > > > { > > > struct pcap_sf_pkthdr hdr; > > > int64_t ts; > > > int caplen; > > > - size_t size = iov_size(iov, cnt); > > > + size_t size = iov_size(iov, cnt) - offset; > > > struct iovec dumpiov[cnt + 1]; > > > /* Early return in case of previous error. */ > > > @@ -84,7 +85,7 @@ static ssize_t dump_receive_iov(DumpState *s, const > > > struct iovec *iov, int cnt) > > > dumpiov[0].iov_base = &hdr; > > > dumpiov[0].iov_len = sizeof(hdr); > > > - cnt = iov_copy(&dumpiov[1], cnt, iov, cnt, 0, caplen); > > > + cnt = iov_copy(&dumpiov[1], cnt, iov, cnt, offset, caplen); > > > if (writev(s->fd, dumpiov, cnt + 1) != sizeof(hdr) + caplen) { > > > error_report("network dump write error - stopping dump"); > > > @@ -153,8 +154,10 @@ static ssize_t > > > filter_dump_receive_iov(NetFilterState *nf, NetClientState *sndr, > > > int iovcnt, NetPacketSent > > > *sent_cb) > > > { > > > NetFilterDumpState *nfds = FILTER_DUMP(nf); > > > + int offset = qemu_get_using_vnet_hdr(nf->netdev) ? > > > + qemu_get_vnet_hdr_len(nf->netdev) : 0; > > > - dump_receive_iov(&nfds->ds, iov, iovcnt); > > > + dump_receive_iov(&nfds->ds, iov, iovcnt, offset); > > > return 0; > > > } > > > diff --git a/net/net.c b/net/net.c > > > index 2d01472998..03f17de5fc 100644 > > > --- a/net/net.c > > > +++ b/net/net.c > > > @@ -513,6 +513,15 @@ bool qemu_has_vnet_hdr_len(NetClientState *nc, int > > > len) > > > return nc->info->has_vnet_hdr_len(nc, len); > > > } > > > +bool qemu_get_using_vnet_hdr(NetClientState *nc) > > > +{ > > > + if (!nc || !nc->info->get_using_vnet_hdr) { > > > + return false; > > > + } > > > + > > > + return nc->info->get_using_vnet_hdr(nc); > > > +} > > > + > > > void qemu_using_vnet_hdr(NetClientState *nc, bool enable) > > > { > > > if (!nc || !nc->info->using_vnet_hdr) { > > > @@ -532,6 +541,15 @@ void qemu_set_offload(NetClientState *nc, int csum, > > > int tso4, int tso6, > > > nc->info->set_offload(nc, csum, tso4, tso6, ecn, ufo); > > > } > > > +int qemu_get_vnet_hdr_len(NetClientState *nc) > > > +{ > > > + if (!nc || !nc->info->get_vnet_hdr_len) { > > > + return 0; > > > + } > > > + > > > + return nc->info->get_vnet_hdr_len(nc); > > > +} > > > + > > > void qemu_set_vnet_hdr_len(NetClientState *nc, int len) > > > { > > > if (!nc || !nc->info->set_vnet_hdr_len) { > > > diff --git a/net/tap.c b/net/tap.c > > > index 7d7bc1dc5f..1bf085d422 100644 > > > --- a/net/tap.c > > > +++ b/net/tap.c > > > @@ -255,6 +255,13 @@ static bool tap_has_vnet_hdr_len(NetClientState *nc, > > > int len) > > > return !!tap_probe_vnet_hdr_len(s->fd, len); > > > } > > > +static int tap_get_vnet_hdr_len(NetClientState *nc) > > > +{ > > > + TAPState *s = DO_UPCAST(TAPState, nc, nc); > > > + > > > + return s->host_vnet_hdr_len; > > > +} > > > + > > > static void tap_set_vnet_hdr_len(NetClientState *nc, int len) > > > { > > > TAPState *s = DO_UPCAST(TAPState, nc, nc); > > > @@ -268,6 +275,13 @@ static void tap_set_vnet_hdr_len(NetClientState *nc, > > > int len) > > > s->host_vnet_hdr_len = len; > > > } > > > +static bool tap_get_using_vnet_hdr(NetClientState *nc) > > > +{ > > > + TAPState *s = DO_UPCAST(TAPState, nc, nc); > > > + > > > + return s->using_vnet_hdr; > > > +} > > > + > > > static void tap_using_vnet_hdr(NetClientState *nc, bool using_vnet_hdr) > > > { > > > TAPState *s = DO_UPCAST(TAPState, nc, nc); > > > @@ -372,8 +386,10 @@ static NetClientInfo net_tap_info = { > > > .has_ufo = tap_has_ufo, > > > .has_vnet_hdr = tap_has_vnet_hdr, > > > .has_vnet_hdr_len = tap_has_vnet_hdr_len, > > > + .get_using_vnet_hdr = tap_get_using_vnet_hdr, > > > .using_vnet_hdr = tap_using_vnet_hdr, > > > .set_offload = tap_set_offload, > > > + .get_vnet_hdr_len = tap_get_vnet_hdr_len, > > > .set_vnet_hdr_len = tap_set_vnet_hdr_len, > > > .set_vnet_le = tap_set_vnet_le, > > > .set_vnet_be = tap_set_vnet_be, > > > -- > > > 2.39.1 > >