Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Martin KaFai Lau says:

====================
pull-request: bpf-next 2023-08-03

We've added 54 non-merge commits during the last 10 day(s) which contain
a total of 84 files changed, 4026 insertions(+), 562 deletions(-).

The main changes are:

1) Add SO_REUSEPORT support for TC bpf_sk_assign from Lorenz Bauer,
   Daniel Borkmann

2) Support new insns from cpu v4 from Yonghong Song

3) Non-atomically allocate freelist during prefill from YiFei Zhu

4) Support defragmenting IPv(4|6) packets in BPF from Daniel Xu

5) Add tracepoint to xdp attaching failure from Leon Hwang

6) struct netdev_rx_queue and xdp.h reshuffling to reduce
   rebuild time from Jakub Kicinski

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits)
  net: invert the netdevice.h vs xdp.h dependency
  net: move struct netdev_rx_queue out of netdevice.h
  eth: add missing xdp.h includes in drivers
  selftests/bpf: Add testcase for xdp attaching failure tracepoint
  bpf, xdp: Add tracepoint to xdp attaching failure
  selftests/bpf: fix static assert compilation issue for test_cls_*.c
  bpf: fix bpf_probe_read_kernel prototype mismatch
  riscv, bpf: Adapt bpf trampoline to optimized riscv ftrace framework
  libbpf: fix typos in Makefile
  tracing: bpf: use struct trace_entry in struct syscall_tp_t
  bpf, devmap: Remove unused dtab field from bpf_dtab_netdev
  bpf, cpumap: Remove unused cmap field from bpf_cpu_map_entry
  netfilter: bpf: Only define get_proto_defrag_hook() if necessary
  bpf: Fix an array-index-out-of-bounds issue in disasm.c
  net: remove duplicate INDIRECT_CALLABLE_DECLARE of udp[6]_ehashfn
  docs/bpf: Fix malformed documentation
  bpf: selftests: Add defrag selftests
  bpf: selftests: Support custom type and proto for client sockets
  bpf: selftests: Support not connecting client socket
  netfilter: bpf: Support BPF_F_NETFILTER_IP_DEFRAG in netfilter link
  ...
====================

Link: https://lore.kernel.org/r/20230803174845.825419-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 90 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/generate_udp_fragments.py b/tools/testing/selftests/bpf/generate_udp_fragments.py
new file mode 100755
index 000000000000..2b8a1187991c
--- /dev/null
+++ b/tools/testing/selftests/bpf/generate_udp_fragments.py
@@ -0,0 +1,90 @@
+#!/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+"""
+This script helps generate fragmented UDP packets.
+
+While it is technically possible to dynamically generate
+fragmented packets in C, it is much harder to read and write
+said code. `scapy` is relatively industry standard and really
+easy to read / write.
+
+So we choose to write this script that generates a valid C
+header. Rerun script and commit generated file after any
+modifications.
+"""
+
+import argparse
+import os
+
+from scapy.all import *
+
+
+# These constants must stay in sync with `ip_check_defrag.c`
+VETH1_ADDR = "172.16.1.200"
+VETH0_ADDR6 = "fc00::100"
+VETH1_ADDR6 = "fc00::200"
+CLIENT_PORT = 48878
+SERVER_PORT = 48879
+MAGIC_MESSAGE = "THIS IS THE ORIGINAL MESSAGE, PLEASE REASSEMBLE ME"
+
+
+def print_header(f):
+    f.write("// SPDX-License-Identifier: GPL-2.0\n")
+    f.write("/* DO NOT EDIT -- this file is generated */\n")
+    f.write("\n")
+    f.write("#ifndef _IP_CHECK_DEFRAG_FRAGS_H\n")
+    f.write("#define _IP_CHECK_DEFRAG_FRAGS_H\n")
+    f.write("\n")
+    f.write("#include <stdint.h>\n")
+    f.write("\n")
+
+
+def print_frags(f, frags, v6):
+    for idx, frag in enumerate(frags):
+        # 10 bytes per line to keep width in check
+        chunks = [frag[i : i + 10] for i in range(0, len(frag), 10)]
+        chunks_fmted = [", ".join([str(hex(b)) for b in chunk]) for chunk in chunks]
+        suffix = "6" if v6 else ""
+
+        f.write(f"static uint8_t frag{suffix}_{idx}[] = {{\n")
+        for chunk in chunks_fmted:
+            f.write(f"\t{chunk},\n")
+        f.write(f"}};\n")
+
+
+def print_trailer(f):
+    f.write("\n")
+    f.write("#endif /* _IP_CHECK_DEFRAG_FRAGS_H */\n")
+
+
+def main(f):
+    # srcip of 0 is filled in by IP_HDRINCL
+    sip = "0.0.0.0"
+    sip6 = VETH0_ADDR6
+    dip = VETH1_ADDR
+    dip6 = VETH1_ADDR6
+    sport = CLIENT_PORT
+    dport = SERVER_PORT
+    payload = MAGIC_MESSAGE.encode()
+
+    # Disable UDPv4 checksums to keep code simpler
+    pkt = IP(src=sip,dst=dip) / UDP(sport=sport,dport=dport,chksum=0) / Raw(load=payload)
+    # UDPv6 requires a checksum
+    # Also pin the ipv6 fragment header ID, otherwise it's a random value
+    pkt6 = IPv6(src=sip6,dst=dip6) / IPv6ExtHdrFragment(id=0xBEEF) / UDP(sport=sport,dport=dport) / Raw(load=payload)
+
+    frags = [f.build() for f in pkt.fragment(24)]
+    frags6 = [f.build() for f in fragment6(pkt6, 72)]
+
+    print_header(f)
+    print_frags(f, frags, False)
+    print_frags(f, frags6, True)
+    print_trailer(f)
+
+
+if __name__ == "__main__":
+    dir = os.path.dirname(os.path.realpath(__file__))
+    header = f"{dir}/ip_check_defrag_frags.h"
+    with open(header, "w") as f:
+        main(f)