1 files changed, 158 insertions, 0 deletions
diff --git a/tests/sys/netpfil/pf/tcp.py b/tests/sys/netpfil/pf/tcp.py
new file mode 100644
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+++ b/tests/sys/netpfil/pf/tcp.py
@@ -0,0 +1,158 @@
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Copyright (c) 2025 Rubicon Communications, LLC (Netgate)
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+import sys
+import pytest
+import random
+import socket
+import selectors
+from utils import DelayedSend
+from atf_python.sys.net.tools import ToolsHelper
+from atf_python.sys.net.vnet import VnetTestTemplate
+
+class TCPClient:
+    def __init__(self, src, dst, sport, dport, sp):
+        self.src = src
+        self.dst = dst
+        self.sport = sport
+        self.dport = dport
+        self.sp = sp
+        self.seq = random.randrange(1, (2**32)-1)
+        self.ack = 0
+
+    def syn(self):
+        syn = self.sp.IP(src=self.src, dst=self.dst) \
+            / self.sp.TCP(sport=self.sport, dport=self.dport, flags="S", seq=self.seq)
+        return syn
+    
+    def connect(self):
+        syn = self.syn()
+        r = self.sp.sr1(syn, timeout=5)
+
+        assert r
+        t = r.getlayer(self.sp.TCP)
+        assert t
+        assert t.sport == self.dport
+        assert t.dport == self.sport
+        assert t.flags == "SA"
+
+        self.seq += 1
+        self.ack = t.seq + 1
+        ack = self.sp.IP(src=self.src, dst=self.dst) \
+            / self.sp.TCP(sport=self.sport, dport=self.dport, flags="A", ack=self.ack, seq=self.seq)
+        self.sp.send(ack)
+
+    def send(self, data):
+        length = len(data)
+        pkt = self.sp.IP(src=self.src, dst=self.dst) \
+            / self.sp.TCP(sport=self.sport, dport=self.dport, ack=self.ack, seq=self.seq, flags="") \
+            / self.sp.Raw(data)
+        self.seq += length
+        pkt.show()
+        self.sp.send(pkt)
+
+class TestTcp(VnetTestTemplate):
+    REQUIRED_MODULES = [ "pf" ]
+    TOPOLOGY = {
+        "vnet1": {"ifaces": ["if1"]},
+        "vnet2": {"ifaces": ["if1"]},
+        "if1": {"prefixes4": [("192.0.2.1/24", "192.0.2.2/24")]},
+    }
+
+    def vnet2_handler(self, vnet):
+        ToolsHelper.print_output("/usr/sbin/arp -s 192.0.2.3 00:01:02:03:04:05")
+        ToolsHelper.print_output("/sbin/pfctl -e")
+        ToolsHelper.pf_rules([
+            "pass"
+        ])
+        ToolsHelper.print_output("/sbin/pfctl -x loud")
+
+        # Start TCP listener
+        sel = selectors.DefaultSelector()
+        t = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        t.bind(("0.0.0.0", 1234))
+        t.listen(100)
+        t.setblocking(False)
+        sel.register(t, selectors.EVENT_READ, data=None)
+
+        while True:
+            events = sel.select(timeout=2)
+            for key, mask in events:
+                sock = key.fileobj
+                if key.data is None:
+                    conn, addr = sock.accept()
+                    print(f"Accepted connection from {addr}")
+                    events = selectors.EVENT_READ | selectors.EVENT_WRITE
+                    sel.register(conn, events, data="TCP")
+                else:
+                    if mask & selectors.EVENT_READ:
+                        recv_data = sock.recv(1024)
+                        print(f"Received TCP {recv_data}")
+                        ToolsHelper.print_output("/sbin/pfctl -ss -vv")
+                        sock.send(recv_data)
+
+    @pytest.mark.require_user("root")
+    @pytest.mark.require_progs(["scapy"])
+    def test_challenge_ack(self):
+        vnet = self.vnet_map["vnet1"]
+        ifname = vnet.iface_alias_map["if1"].name
+
+        # Import in the correct vnet, so at to not confuse Scapy
+        import scapy.all as sp
+
+        a = TCPClient("192.0.2.3", "192.0.2.2", 1234, 1234, sp)
+        a.connect()
+        a.send(b"foo")
+
+        b = TCPClient("192.0.2.3", "192.0.2.2", 1234, 1234, sp)
+        syn = b.syn()
+        syn.show()
+        s = DelayedSend(syn)
+        packets = sp.sniff(iface=ifname, timeout=3)
+        found = False
+        for p in packets:
+            ip = p.getlayer(sp.IP)
+            if not ip:
+                continue
+            tcp = p.getlayer(sp.TCP)
+            if not tcp:
+                continue
+
+            if ip.src != "192.0.2.2":
+                continue
+
+            p.show()
+
+            assert ip.dst == "192.0.2.3"
+            assert tcp.sport == 1234
+            assert tcp.dport == 1234
+            assert tcp.flags == "A"
+
+            # We only expect one
+            assert not found
+            found = True
+
+        assert found