On Fri, Jun 14, 2024 at 01:07:33PM GMT, Aaron Conole wrote:
> Adrian Moreno <amorenoz@xxxxxxxxxx> writes:
>
> > Add a test to verify sampling packets via psample works.
> >
> > In order to do that, create a subcommand in ovs-dpctl.py to listen to
> > on the psample multicast group and print samples.
> >
> > In order to also test simultaneous sFlow and psample actions and
> > packet truncation, add missing parsing support for "userspace" and
> > "trunc" actions.
>
> Maybe split that into a separate patch. This has a bugfix and 3
> features being pushed in. I know it's already getting long as a series,
> so maybe it's okay to fold the userspace attribute bugfix with the parse
> support (since it wasn't really usable before).
>
OK. Sounds reasonable.
> > Signed-off-by: Adrian Moreno <amorenoz@xxxxxxxxxx>
> > ---
> > .../selftests/net/openvswitch/openvswitch.sh | 99 +++++++++++++++-
> > .../selftests/net/openvswitch/ovs-dpctl.py | 112 +++++++++++++++++-
> > 2 files changed, 204 insertions(+), 7 deletions(-)
> >
> > diff --git a/tools/testing/selftests/net/openvswitch/openvswitch.sh b/tools/testing/selftests/net/openvswitch/openvswitch.sh
> > index 5cae53543849..f6e0ae3f6424 100755
> > --- a/tools/testing/selftests/net/openvswitch/openvswitch.sh
> > +++ b/tools/testing/selftests/net/openvswitch/openvswitch.sh
> > @@ -20,7 +20,8 @@ tests="
> > nat_related_v4 ip4-nat-related: ICMP related matches work with SNAT
> > netlink_checks ovsnl: validate netlink attrs and settings
> > upcall_interfaces ovs: test the upcall interfaces
> > - drop_reason drop: test drop reasons are emitted"
> > + drop_reason drop: test drop reasons are emitted
> > + emit_sample emit_sample: Sampling packets with psample"
> >
> > info() {
> > [ $VERBOSE = 0 ] || echo $*
> > @@ -170,6 +171,19 @@ ovs_drop_reason_count()
> > return `echo "$perf_output" | grep "$pattern" | wc -l`
> > }
> >
> > +ovs_test_flow_fails () {
> > + ERR_MSG="Flow actions may not be safe on all matching packets"
> > +
> > + PRE_TEST=$(dmesg | grep -c "${ERR_MSG}")
> > + ovs_add_flow $@ &> /dev/null $@ && return 1
> > + POST_TEST=$(dmesg | grep -c "${ERR_MSG}")
> > +
> > + if [ "$PRE_TEST" == "$POST_TEST" ]; then
> > + return 1
> > + fi
> > + return 0
> > +}
> > +
> > usage() {
> > echo
> > echo "$0 [OPTIONS] [TEST]..."
> > @@ -184,6 +198,89 @@ usage() {
> > exit 1
> > }
> >
> > +
> > +# emit_sample test
> > +# - use emit_sample to observe packets
> > +test_emit_sample() {
> > + sbx_add "test_emit_sample" || return $?
> > +
> > + # Add a datapath with per-vport dispatching.
> > + ovs_add_dp "test_emit_sample" emit_sample -V 2:1 || return 1
> > +
> > + info "create namespaces"
> > + ovs_add_netns_and_veths "test_emit_sample" "emit_sample" \
> > + client c0 c1 172.31.110.10/24 -u || return 1
> > + ovs_add_netns_and_veths "test_emit_sample" "emit_sample" \
> > + server s0 s1 172.31.110.20/24 -u || return 1
> > +
> > + # Check if emit_sample actions can be configured.
> > + ovs_add_flow "test_emit_sample" emit_sample \
> > + 'in_port(1),eth(),eth_type(0x0806),arp()' 'emit_sample(group=1)'
> > + if [ $? == 1 ]; then
> > + info "no support for emit_sample - skipping"
> > + ovs_exit_sig
> > + return $ksft_skip
> > + fi
> > +
> > + ovs_del_flows "test_emit_sample" emit_sample
> > +
> > + # Allow ARP
> > + ovs_add_flow "test_emit_sample" emit_sample \
> > + 'in_port(1),eth(),eth_type(0x0806),arp()' '2' || return 1
> > + ovs_add_flow "test_emit_sample" emit_sample \
> > + 'in_port(2),eth(),eth_type(0x0806),arp()' '1' || return 1
> > +
> > + # Test action verification.
> > + OLDIFS=$IFS
> > + IFS='*'
> > + min_key='in_port(1),eth(),eth_type(0x0800),ipv4()'
> > + for testcase in \
> > + "cookie to large"*"emit_sample(group=1,cookie=1615141312111009080706050403020100)" \
> > + "no group with cookie"*"emit_sample(cookie=abcd)" \
> > + "no group"*"sample()";
> > + do
> > + set -- $testcase;
> > + ovs_test_flow_fails "test_emit_sample" emit_sample $min_key $2
> > + if [ $? == 1 ]; then
> > + info "failed - $1"
> > + return 1
> > + fi
> > + done
> > + IFS=$OLDIFS
> > +
> > + # Sample first 14 bytes of all traffic.
> > + ovs_add_flow "test_emit_sample" emit_sample \
> > + "in_port(1),eth(),eth_type(0x0800),ipv4(src=172.31.110.10,proto=1),icmp()" "trunc(14),emit_sample(group=1,cookie=c0ffee),2"
> > +
> > + # Sample all traffic. In this case, use a sample() action with both
> > + # emit_sample and an upcall emulating simultaneous local sampling and
> > + # sFlow / IPFIX.
> > + nlpid=$(grep -E "listening on upcall packet handler" $ovs_dir/s0.out | cut -d ":" -f 2 | tr -d ' ')
> > + ovs_add_flow "test_emit_sample" emit_sample \
> > + "in_port(2),eth(),eth_type(0x0800),ipv4(src=172.31.110.20,proto=1),icmp()" "sample(sample=100%,actions(emit_sample(group=2,cookie=eeff0c),userspace(pid=${nlpid},userdata=eeff0c))),1"
> > +
> > + # Record emit_sample data.
> > + python3 $ovs_base/ovs-dpctl.py psample >$ovs_dir/psample.out 2>$ovs_dir/psample.err &
> > + pid=$!
> > + on_exit "ovs_sbx test_emit_sample kill -TERM $pid 2>/dev/null"
>
> Maybe ovs_netns_spawn_daemon ?
>
I'll take a look at it, thanks.
> > +
> > + # Send a single ping.
> > + sleep 1
> > + ovs_sbx "test_emit_sample" ip netns exec client ping -I c1 172.31.110.20 -c 1 || return 1
> > + sleep 1
> > +
> > + # We should have received one userspace action upcall and 2 psample packets.
> > + grep -E "userspace action command" $ovs_dir/s0.out >/dev/null 2>&1 || return 1
> > +
> > + # client -> server samples should only contain the first 14 bytes of the packet.
> > + grep -E "rate:4294967295,group:1,cookie:c0ffee data:[0-9a-f]{28}$" \
> > + $ovs_dir/psample.out >/dev/null 2>&1 || return 1
> > + grep -E "rate:4294967295,group:2,cookie:eeff0c" \
> > + $ovs_dir/psample.out >/dev/null 2>&1 || return 1
> > +
> > + return 0
> > +}
> > +
> > # drop_reason test
> > # - drop packets and verify the right drop reason is reported
> > test_drop_reason() {
> > diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
> > index f8b5362aac8c..44fdeb9491a2 100644
> > --- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
> > +++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py
> > @@ -27,8 +27,10 @@ try:
> > from pyroute2.netlink import genlmsg
> > from pyroute2.netlink import nla
> > from pyroute2.netlink import nlmsg_atoms
> > - from pyroute2.netlink.exceptions import NetlinkError
> > + from pyroute2.netlink.event import EventSocket
> > from pyroute2.netlink.generic import GenericNetlinkSocket
> > + from pyroute2.netlink.nlsocket import Marshal
> > + from pyroute2.netlink.exceptions import NetlinkError
>
> Why did this get moved?
>
I guess I first removed it and then added it in the wrong order. I'll
restore it, thanks.
> > import pyroute2
> >
> > except ModuleNotFoundError:
> > @@ -575,13 +577,27 @@ class ovsactions(nla):
> > print_str += "userdata="
> > for f in self.get_attr("OVS_USERSPACE_ATTR_USERDATA"):
> > print_str += "%x." % f
> > - if self.get_attr("OVS_USERSPACE_ATTR_TUN_PORT") is not None:
> > + if self.get_attr("OVS_USERSPACE_ATTR_EGRESS_TUN_PORT") is not None:
> > print_str += "egress_tun_port=%d" % self.get_attr(
> > - "OVS_USERSPACE_ATTR_TUN_PORT"
> > + "OVS_USERSPACE_ATTR_EGRESS_TUN_PORT"
>
> Looks like a bugfix here.
>
Yep. I'll fold it in with the rest of the usersapce action support into
an independent patch.
> > )
> > print_str += ")"
> > return print_str
> >
> > + def parse(self, actstr):
> > + attrs_desc = (
> > + ("pid", "OVS_USERSPACE_ATTR_PID", int),
> > + ("userdata", "OVS_USERSPACE_ATTR_USERDATA",
> > + lambda x: list(bytearray.fromhex(x))),
> > + ("egress_tun_port", "OVS_USERSPACE_ATTR_EGRESS_TUN_PORT", int)
> > + )
> > +
> > + attrs, actstr = parse_attrs(actstr, attrs_desc)
> > + for attr in attrs:
> > + self["attrs"].append(attr)
> > +
> > + return actstr
> > +
> > def dpstr(self, more=False):
> > print_str = ""
> >
> > @@ -803,6 +819,25 @@ class ovsactions(nla):
> > self["attrs"].append(["OVS_ACTION_ATTR_EMIT_SAMPLE", emitact])
> > parsed = True
> >
> > + elif parse_starts_block(actstr, "userspace(", False):
> > + uact = self.userspace()
> > + actstr = uact.parse(actstr[len("userpsace(") : ])
> > + self["attrs"].append(["OVS_ACTION_ATTR_USERSPACE", uact])
> > + parsed = True
> > +
> > + elif parse_starts_block(actstr, "trunc", False):
>
> This should be "trunc("
>
Probably, yes. The rest of the actions do look for the initial "(".
Thinking in a generalization of the action parsing, could we just look
for the action name, i.e: "trunc" and let errors be raised inside each
parsing logic? In this case, check if "val is not None" after
"parse_extract_field".
> > + parencount += 1
> > + actstr, val = parse_extract_field(
> > + actstr,
> > + "trunc(",
> > + r"([0-9]+)",
> > + int,
> > + False,
> > + None,
> > + )
> > + self["attrs"].append(["OVS_ACTION_ATTR_TRUNC", val])
> > + parsed = True
> > +
> > actstr = actstr[strspn(actstr, ", ") :]
> > while parencount > 0:
> > parencount -= 1
> > @@ -2184,10 +2219,70 @@ class OvsFlow(GenericNetlinkSocket):
> > print("MISS upcall[%d/%s]: %s" % (seq, pktpres, keystr), flush=True)
> >
> > def execute(self, packetmsg):
> > - print("userspace execute command")
> > + print("userspace execute command", flush=True)
> >
> > def action(self, packetmsg):
> > - print("userspace action command")
> > + print("userspace action command", flush=True)
> > +
> > +
> > +class psample_sample(genlmsg):
> > + nla_map = (
> > + ("PSAMPLE_ATTR_IIFINDEX", "none"),
> > + ("PSAMPLE_ATTR_OIFINDEX", "none"),
> > + ("PSAMPLE_ATTR_ORIGSIZE", "none"),
> > + ("PSAMPLE_ATTR_SAMPLE_GROUP", "uint32"),
> > + ("PSAMPLE_ATTR_GROUP_SEQ", "none"),
> > + ("PSAMPLE_ATTR_SAMPLE_RATE", "uint32"),
> > + ("PSAMPLE_ATTR_DATA", "array(uint8)"),
> > + ("PSAMPLE_ATTR_GROUP_REFCOUNT", "none"),
> > + ("PSAMPLE_ATTR_TUNNEL", "none"),
> > + ("PSAMPLE_ATTR_PAD", "none"),
> > + ("PSAMPLE_ATTR_OUT_TC", "none"),
> > + ("PSAMPLE_ATTR_OUT_TC_OCC", "none"),
> > + ("PSAMPLE_ATTR_LATENCY", "none"),
> > + ("PSAMPLE_ATTR_TIMESTAMP", "none"),
> > + ("PSAMPLE_ATTR_PROTO", "none"),
> > + ("PSAMPLE_ATTR_USER_COOKIE", "array(uint8)"),
> > + )
> > +
> > + def dpstr(self):
> > + fields = []
> > + data = ""
> > + for (attr, value) in self["attrs"]:
> > + if attr == "PSAMPLE_ATTR_SAMPLE_GROUP":
> > + fields.append("group:%d" % value)
> > + if attr == "PSAMPLE_ATTR_SAMPLE_RATE":
> > + fields.append("rate:%d" % value)
> > + if attr == "PSAMPLE_ATTR_USER_COOKIE":
> > + value = "".join(format(x, "02x") for x in value)
> > + fields.append("cookie:%s" % value)
> > + if attr == "PSAMPLE_ATTR_DATA" and len(value) > 0:
> > + data = "data:%s" % "".join(format(x, "02x") for x in value)
> > +
> > + return ("%s %s" % (",".join(fields), data)).strip()
> > +
> > +
> > +class psample_msg(Marshal):
> > + PSAMPLE_CMD_SAMPLE = 0
> > + PSAMPLE_CMD_GET_GROUP = 1
> > + PSAMPLE_CMD_NEW_GROUP = 2
> > + PSAMPLE_CMD_DEL_GROUP = 3
> > + PSAMPLE_CMD_SET_FILTER = 4
> > + msg_map = {PSAMPLE_CMD_SAMPLE: psample_sample}
> > +
> > +
> > +class Psample(EventSocket):
> > + genl_family = "psample"
> > + mcast_groups = ["packets"]
> > + marshal_class = psample_msg
> > +
> > + def read_samples(self):
> > + while True:
> > + try:
> > + for msg in self.get():
> > + print(msg.dpstr(), flush=True)
> > + except NetlinkError as ne:
> > + raise ne
> >
> >
> > def print_ovsdp_full(dp_lookup_rep, ifindex, ndb=NDB(), vpl=OvsVport()):
> > @@ -2247,7 +2342,7 @@ def main(argv):
> > help="Increment 'verbose' output counter.",
> > default=0,
> > )
> > - subparsers = parser.add_subparsers()
> > + subparsers = parser.add_subparsers(dest="subcommand")
> >
> > showdpcmd = subparsers.add_parser("show")
> > showdpcmd.add_argument(
> > @@ -2304,6 +2399,8 @@ def main(argv):
> > delfscmd = subparsers.add_parser("del-flows")
> > delfscmd.add_argument("flsbr", help="Datapath name")
> >
> > + subparsers.add_parser("psample")
> > +
> > args = parser.parse_args()
> >
> > if args.verbose > 0:
> > @@ -2318,6 +2415,9 @@ def main(argv):
> >
> > sys.setrecursionlimit(100000)
> >
> > + if args.subcommand == "psample":
> > + Psample().read_samples()
> > +
> > if hasattr(args, "showdp"):
> > found = False
> > for iface in ndb.interfaces:
>
