From: Jakub Kicinski <kuba@kernel.org>
Date: Tue, 23 Apr 2024 18:35:41 +0000 (-0700)
Subject: selftests: net: name bpf objects consistently and simplify Makefile
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=6b88ce902f0bdcb3694a6ceddc8b3d0b40db3772;p=linux.git
selftests: net: name bpf objects consistently and simplify Makefile
The BPF sources moved with bpf_offload.py have a suffix of .bpf.c
which seems to be useful convention. Rename the 2 other BPF sources
we had. Use wildcard in the Makefile, since we can match all those
files easily now.
Link: https://lore.kernel.org/r/20240423183542.3807234-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 7e7f243d0ab2a..c388308ff5178 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -82,10 +82,6 @@ TEST_GEN_PROGS += so_incoming_cpu
TEST_PROGS += sctp_vrf.sh
TEST_GEN_FILES += sctp_hello
TEST_GEN_FILES += csum
-TEST_GEN_FILES += nat6to4.o
-TEST_GEN_FILES += xdp_dummy.o
-TEST_GEN_FILES += sample_ret0.bpf.o
-TEST_GEN_FILES += sample_map_ret0.bpf.o
TEST_GEN_FILES += ip_local_port_range
TEST_GEN_FILES += bind_wildcard
TEST_PROGS += test_vxlan_mdb.sh
@@ -100,6 +96,8 @@ TEST_PROGS += bpf_offload.py
TEST_FILES := settings
TEST_FILES += in_netns.sh lib.sh net_helper.sh setup_loopback.sh setup_veth.sh
+TEST_GEN_FILES += $(patsubst %.c,%.o,$(wildcard *.bpf.c))
+
TEST_INCLUDES := forwarding/lib.sh
include ../lib.mk
@@ -146,8 +144,7 @@ endif
CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH))
-BPF_PROG_OBJS := $(OUTPUT)/nat6to4.o $(OUTPUT)/xdp_dummy.o \
- $(OUTPUT)/sample_map_ret0.bpf.o $(OUTPUT)/sample_ret0.bpf.o
+BPF_PROG_OBJS := $(patsubst %.c,$(OUTPUT)/%.o,$(wildcard *.bpf.c))
$(BPF_PROG_OBJS): $(OUTPUT)/%.o : %.c $(BPFOBJ) | $(MAKE_DIRS)
$(call msg,BPF_PROG,,$@)
diff --git a/tools/testing/selftests/net/nat6to4.bpf.c b/tools/testing/selftests/net/nat6to4.bpf.c
new file mode 100644
index 0000000000000..ac54c36b25fc8
--- /dev/null
+++ b/tools/testing/selftests/net/nat6to4.bpf.c
@@ -0,0 +1,285 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * This code is taken from the Android Open Source Project and the author
+ * (Maciej Żenczykowski) has gave permission to relicense it under the
+ * GPLv2. Therefore this program is free software;
+ * You can redistribute it and/or modify it under the terms of the GNU
+ * General Public License version 2 as published by the Free Software
+ * Foundation
+
+ * The original headers, including the original license headers, are
+ * included below for completeness.
+ *
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <linux/bpf.h>
+#include <linux/if.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/pkt_cls.h>
+#include <linux/swab.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+
+#include <linux/udp.h>
+
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
+
+#define IP_DF 0x4000 // Flag: "Don't Fragment"
+
+SEC("schedcls/ingress6/nat_6")
+int sched_cls_ingress6_nat_6_prog(struct __sk_buff *skb)
+{
+ const int l2_header_size = sizeof(struct ethhdr);
+ void *data = (void *)(long)skb->data;
+ const void *data_end = (void *)(long)skb->data_end;
+ const struct ethhdr * const eth = data; // used iff is_ethernet
+ const struct ipv6hdr * const ip6 = (void *)(eth + 1);
+
+ // Require ethernet dst mac address to be our unicast address.
+ if (skb->pkt_type != PACKET_HOST)
+ return TC_ACT_OK;
+
+ // Must be meta-ethernet IPv6 frame
+ if (skb->protocol != bpf_htons(ETH_P_IPV6))
+ return TC_ACT_OK;
+
+ // Must have (ethernet and) ipv6 header
+ if (data + l2_header_size + sizeof(*ip6) > data_end)
+ return TC_ACT_OK;
+
+ // Ethertype - if present - must be IPv6
+ if (eth->h_proto != bpf_htons(ETH_P_IPV6))
+ return TC_ACT_OK;
+
+ // IP version must be 6
+ if (ip6->version != 6)
+ return TC_ACT_OK;
+ // Maximum IPv6 payload length that can be translated to IPv4
+ if (bpf_ntohs(ip6->payload_len) > 0xFFFF - sizeof(struct iphdr))
+ return TC_ACT_OK;
+ switch (ip6->nexthdr) {
+ case IPPROTO_TCP: // For TCP & UDP the checksum neutrality of the chosen IPv6
+ case IPPROTO_UDP: // address means there is no need to update their checksums.
+ case IPPROTO_GRE: // We do not need to bother looking at GRE/ESP headers,
+ case IPPROTO_ESP: // since there is never a checksum to update.
+ break;
+ default: // do not know how to handle anything else
+ return TC_ACT_OK;
+ }
+
+ struct ethhdr eth2; // used iff is_ethernet
+
+ eth2 = *eth; // Copy over the ethernet header (src/dst mac)
+ eth2.h_proto = bpf_htons(ETH_P_IP); // But replace the ethertype
+
+ struct iphdr ip = {
+ .version = 4, // u4
+ .ihl = sizeof(struct iphdr) / sizeof(__u32), // u4
+ .tos = (ip6->priority << 4) + (ip6->flow_lbl[0] >> 4), // u8
+ .tot_len = bpf_htons(bpf_ntohs(ip6->payload_len) + sizeof(struct iphdr)), // u16
+ .id = 0, // u16
+ .frag_off = bpf_htons(IP_DF), // u16
+ .ttl = ip6->hop_limit, // u8
+ .protocol = ip6->nexthdr, // u8
+ .check = 0, // u16
+ .saddr = 0x0201a8c0, // u32
+ .daddr = 0x0101a8c0, // u32
+ };
+
+ // Calculate the IPv4 one's complement checksum of the IPv4 header.
+ __wsum sum4 = 0;
+
+ for (int i = 0; i < sizeof(ip) / sizeof(__u16); ++i)
+ sum4 += ((__u16 *)&ip)[i];
+
+ // Note that sum4 is guaranteed to be non-zero by virtue of ip.version == 4
+ sum4 = (sum4 & 0xFFFF) + (sum4 >> 16); // collapse u32 into range 1 .. 0x1FFFE
+ sum4 = (sum4 & 0xFFFF) + (sum4 >> 16); // collapse any potential carry into u16
+ ip.check = (__u16)~sum4; // sum4 cannot be zero, so this is never 0xFFFF
+
+ // Calculate the *negative* IPv6 16-bit one's complement checksum of the IPv6 header.
+ __wsum sum6 = 0;
+ // We'll end up with a non-zero sum due to ip6->version == 6 (which has '0' bits)
+ for (int i = 0; i < sizeof(*ip6) / sizeof(__u16); ++i)
+ sum6 += ~((__u16 *)ip6)[i]; // note the bitwise negation
+
+ // Note that there is no L4 checksum update: we are relying on the checksum neutrality
+ // of the ipv6 address chosen by netd's ClatdController.
+
+ // Packet mutations begin - point of no return, but if this first modification fails
+ // the packet is probably still pristine, so let clatd handle it.
+ if (bpf_skb_change_proto(skb, bpf_htons(ETH_P_IP), 0))
+ return TC_ACT_OK;
+ bpf_csum_update(skb, sum6);
+
+ data = (void *)(long)skb->data;
+ data_end = (void *)(long)skb->data_end;
+ if (data + l2_header_size + sizeof(struct iphdr) > data_end)
+ return TC_ACT_SHOT;
+
+ struct ethhdr *new_eth = data;
+
+ // Copy over the updated ethernet header
+ *new_eth = eth2;
+
+ // Copy over the new ipv4 header.
+ *(struct iphdr *)(new_eth + 1) = ip;
+ return bpf_redirect(skb->ifindex, BPF_F_INGRESS);
+}
+
+SEC("schedcls/egress4/snat4")
+int sched_cls_egress4_snat4_prog(struct __sk_buff *skb)
+{
+ const int l2_header_size = sizeof(struct ethhdr);
+ void *data = (void *)(long)skb->data;
+ const void *data_end = (void *)(long)skb->data_end;
+ const struct ethhdr *const eth = data; // used iff is_ethernet
+ const struct iphdr *const ip4 = (void *)(eth + 1);
+
+ // Must be meta-ethernet IPv4 frame
+ if (skb->protocol != bpf_htons(ETH_P_IP))
+ return TC_ACT_OK;
+
+ // Must have ipv4 header
+ if (data + l2_header_size + sizeof(struct ipv6hdr) > data_end)
+ return TC_ACT_OK;
+
+ // Ethertype - if present - must be IPv4
+ if (eth->h_proto != bpf_htons(ETH_P_IP))
+ return TC_ACT_OK;
+
+ // IP version must be 4
+ if (ip4->version != 4)
+ return TC_ACT_OK;
+
+ // We cannot handle IP options, just standard 20 byte == 5 dword minimal IPv4 header
+ if (ip4->ihl != 5)
+ return TC_ACT_OK;
+
+ // Maximum IPv6 payload length that can be translated to IPv4
+ if (bpf_htons(ip4->tot_len) > 0xFFFF - sizeof(struct ipv6hdr))
+ return TC_ACT_OK;
+
+ // Calculate the IPv4 one's complement checksum of the IPv4 header.
+ __wsum sum4 = 0;
+
+ for (int i = 0; i < sizeof(*ip4) / sizeof(__u16); ++i)
+ sum4 += ((__u16 *)ip4)[i];
+
+ // Note that sum4 is guaranteed to be non-zero by virtue of ip4->version == 4
+ sum4 = (sum4 & 0xFFFF) + (sum4 >> 16); // collapse u32 into range 1 .. 0x1FFFE
+ sum4 = (sum4 & 0xFFFF) + (sum4 >> 16); // collapse any potential carry into u16
+ // for a correct checksum we should get *a* zero, but sum4 must be positive, ie 0xFFFF
+ if (sum4 != 0xFFFF)
+ return TC_ACT_OK;
+
+ // Minimum IPv4 total length is the size of the header
+ if (bpf_ntohs(ip4->tot_len) < sizeof(*ip4))
+ return TC_ACT_OK;
+
+ // We are incapable of dealing with IPv4 fragments
+ if (ip4->frag_off & ~bpf_htons(IP_DF))
+ return TC_ACT_OK;
+
+ switch (ip4->protocol) {
+ case IPPROTO_TCP: // For TCP & UDP the checksum neutrality of the chosen IPv6
+ case IPPROTO_GRE: // address means there is no need to update their checksums.
+ case IPPROTO_ESP: // We do not need to bother looking at GRE/ESP headers,
+ break; // since there is never a checksum to update.
+
+ case IPPROTO_UDP: // See above comment, but must also have UDP header...
+ if (data + sizeof(*ip4) + sizeof(struct udphdr) > data_end)
+ return TC_ACT_OK;
+ const struct udphdr *uh = (const struct udphdr *)(ip4 + 1);
+ // If IPv4/UDP checksum is 0 then fallback to clatd so it can calculate the
+ // checksum. Otherwise the network or more likely the NAT64 gateway might
+ // drop the packet because in most cases IPv6/UDP packets with a zero checksum
+ // are invalid. See RFC 6935. TODO: calculate checksum via bpf_csum_diff()
+ if (!uh->check)
+ return TC_ACT_OK;
+ break;
+
+ default: // do not know how to handle anything else
+ return TC_ACT_OK;
+ }
+ struct ethhdr eth2; // used iff is_ethernet
+
+ eth2 = *eth; // Copy over the ethernet header (src/dst mac)
+ eth2.h_proto = bpf_htons(ETH_P_IPV6); // But replace the ethertype
+
+ struct ipv6hdr ip6 = {
+ .version = 6, // __u8:4
+ .priority = ip4->tos >> 4, // __u8:4
+ .flow_lbl = {(ip4->tos & 0xF) << 4, 0, 0}, // __u8[3]
+ .payload_len = bpf_htons(bpf_ntohs(ip4->tot_len) - 20), // __be16
+ .nexthdr = ip4->protocol, // __u8
+ .hop_limit = ip4->ttl, // __u8
+ };
+ ip6.saddr.in6_u.u6_addr32[0] = bpf_htonl(0x20010db8);
+ ip6.saddr.in6_u.u6_addr32[1] = 0;
+ ip6.saddr.in6_u.u6_addr32[2] = 0;
+ ip6.saddr.in6_u.u6_addr32[3] = bpf_htonl(1);
+ ip6.daddr.in6_u.u6_addr32[0] = bpf_htonl(0x20010db8);
+ ip6.daddr.in6_u.u6_addr32[1] = 0;
+ ip6.daddr.in6_u.u6_addr32[2] = 0;
+ ip6.daddr.in6_u.u6_addr32[3] = bpf_htonl(2);
+
+ // Calculate the IPv6 16-bit one's complement checksum of the IPv6 header.
+ __wsum sum6 = 0;
+ // We'll end up with a non-zero sum due to ip6.version == 6
+ for (int i = 0; i < sizeof(ip6) / sizeof(__u16); ++i)
+ sum6 += ((__u16 *)&ip6)[i];
+
+ // Packet mutations begin - point of no return, but if this first modification fails
+ // the packet is probably still pristine, so let clatd handle it.
+ if (bpf_skb_change_proto(skb, bpf_htons(ETH_P_IPV6), 0))
+ return TC_ACT_OK;
+
+ // This takes care of updating the skb->csum field for a CHECKSUM_COMPLETE packet.
+ // In such a case, skb->csum is a 16-bit one's complement sum of the entire payload,
+ // thus we need to subtract out the ipv4 header's sum, and add in the ipv6 header's sum.
+ // However, we've already verified the ipv4 checksum is correct and thus 0.
+ // Thus we only need to add the ipv6 header's sum.
+ //
+ // bpf_csum_update() always succeeds if the skb is CHECKSUM_COMPLETE and returns an error
+ // (-ENOTSUPP) if it isn't. So we just ignore the return code (see above for more details).
+ bpf_csum_update(skb, sum6);
+
+ // bpf_skb_change_proto() invalidates all pointers - reload them.
+ data = (void *)(long)skb->data;
+ data_end = (void *)(long)skb->data_end;
+
+ // I cannot think of any valid way for this error condition to trigger, however I do
+ // believe the explicit check is required to keep the in kernel ebpf verifier happy.
+ if (data + l2_header_size + sizeof(ip6) > data_end)
+ return TC_ACT_SHOT;
+
+ struct ethhdr *new_eth = data;
+
+ // Copy over the updated ethernet header
+ *new_eth = eth2;
+ // Copy over the new ipv4 header.
+ *(struct ipv6hdr *)(new_eth + 1) = ip6;
+ return TC_ACT_OK;
+}
+
+char _license[] SEC("license") = ("GPL");
diff --git a/tools/testing/selftests/net/nat6to4.c b/tools/testing/selftests/net/nat6to4.c
deleted file mode 100644
index ac54c36b25fc8..0000000000000
--- a/tools/testing/selftests/net/nat6to4.c
+++ /dev/null
@@ -1,285 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * This code is taken from the Android Open Source Project and the author
- * (Maciej Żenczykowski) has gave permission to relicense it under the
- * GPLv2. Therefore this program is free software;
- * You can redistribute it and/or modify it under the terms of the GNU
- * General Public License version 2 as published by the Free Software
- * Foundation
-
- * The original headers, including the original license headers, are
- * included below for completeness.
- *
- * Copyright (C) 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#include <linux/bpf.h>
-#include <linux/if.h>
-#include <linux/if_ether.h>
-#include <linux/if_packet.h>
-#include <linux/in.h>
-#include <linux/in6.h>
-#include <linux/ip.h>
-#include <linux/ipv6.h>
-#include <linux/pkt_cls.h>
-#include <linux/swab.h>
-#include <stdbool.h>
-#include <stdint.h>
-
-
-#include <linux/udp.h>
-
-#include <bpf/bpf_helpers.h>
-#include <bpf/bpf_endian.h>
-
-#define IP_DF 0x4000 // Flag: "Don't Fragment"
-
-SEC("schedcls/ingress6/nat_6")
-int sched_cls_ingress6_nat_6_prog(struct __sk_buff *skb)
-{
- const int l2_header_size = sizeof(struct ethhdr);
- void *data = (void *)(long)skb->data;
- const void *data_end = (void *)(long)skb->data_end;
- const struct ethhdr * const eth = data; // used iff is_ethernet
- const struct ipv6hdr * const ip6 = (void *)(eth + 1);
-
- // Require ethernet dst mac address to be our unicast address.
- if (skb->pkt_type != PACKET_HOST)
- return TC_ACT_OK;
-
- // Must be meta-ethernet IPv6 frame
- if (skb->protocol != bpf_htons(ETH_P_IPV6))
- return TC_ACT_OK;
-
- // Must have (ethernet and) ipv6 header
- if (data + l2_header_size + sizeof(*ip6) > data_end)
- return TC_ACT_OK;
-
- // Ethertype - if present - must be IPv6
- if (eth->h_proto != bpf_htons(ETH_P_IPV6))
- return TC_ACT_OK;
-
- // IP version must be 6
- if (ip6->version != 6)
- return TC_ACT_OK;
- // Maximum IPv6 payload length that can be translated to IPv4
- if (bpf_ntohs(ip6->payload_len) > 0xFFFF - sizeof(struct iphdr))
- return TC_ACT_OK;
- switch (ip6->nexthdr) {
- case IPPROTO_TCP: // For TCP & UDP the checksum neutrality of the chosen IPv6
- case IPPROTO_UDP: // address means there is no need to update their checksums.
- case IPPROTO_GRE: // We do not need to bother looking at GRE/ESP headers,
- case IPPROTO_ESP: // since there is never a checksum to update.
- break;
- default: // do not know how to handle anything else
- return TC_ACT_OK;
- }
-
- struct ethhdr eth2; // used iff is_ethernet
-
- eth2 = *eth; // Copy over the ethernet header (src/dst mac)
- eth2.h_proto = bpf_htons(ETH_P_IP); // But replace the ethertype
-
- struct iphdr ip = {
- .version = 4, // u4
- .ihl = sizeof(struct iphdr) / sizeof(__u32), // u4
- .tos = (ip6->priority << 4) + (ip6->flow_lbl[0] >> 4), // u8
- .tot_len = bpf_htons(bpf_ntohs(ip6->payload_len) + sizeof(struct iphdr)), // u16
- .id = 0, // u16
- .frag_off = bpf_htons(IP_DF), // u16
- .ttl = ip6->hop_limit, // u8
- .protocol = ip6->nexthdr, // u8
- .check = 0, // u16
- .saddr = 0x0201a8c0, // u32
- .daddr = 0x0101a8c0, // u32
- };
-
- // Calculate the IPv4 one's complement checksum of the IPv4 header.
- __wsum sum4 = 0;
-
- for (int i = 0; i < sizeof(ip) / sizeof(__u16); ++i)
- sum4 += ((__u16 *)&ip)[i];
-
- // Note that sum4 is guaranteed to be non-zero by virtue of ip.version == 4
- sum4 = (sum4 & 0xFFFF) + (sum4 >> 16); // collapse u32 into range 1 .. 0x1FFFE
- sum4 = (sum4 & 0xFFFF) + (sum4 >> 16); // collapse any potential carry into u16
- ip.check = (__u16)~sum4; // sum4 cannot be zero, so this is never 0xFFFF
-
- // Calculate the *negative* IPv6 16-bit one's complement checksum of the IPv6 header.
- __wsum sum6 = 0;
- // We'll end up with a non-zero sum due to ip6->version == 6 (which has '0' bits)
- for (int i = 0; i < sizeof(*ip6) / sizeof(__u16); ++i)
- sum6 += ~((__u16 *)ip6)[i]; // note the bitwise negation
-
- // Note that there is no L4 checksum update: we are relying on the checksum neutrality
- // of the ipv6 address chosen by netd's ClatdController.
-
- // Packet mutations begin - point of no return, but if this first modification fails
- // the packet is probably still pristine, so let clatd handle it.
- if (bpf_skb_change_proto(skb, bpf_htons(ETH_P_IP), 0))
- return TC_ACT_OK;
- bpf_csum_update(skb, sum6);
-
- data = (void *)(long)skb->data;
- data_end = (void *)(long)skb->data_end;
- if (data + l2_header_size + sizeof(struct iphdr) > data_end)
- return TC_ACT_SHOT;
-
- struct ethhdr *new_eth = data;
-
- // Copy over the updated ethernet header
- *new_eth = eth2;
-
- // Copy over the new ipv4 header.
- *(struct iphdr *)(new_eth + 1) = ip;
- return bpf_redirect(skb->ifindex, BPF_F_INGRESS);
-}
-
-SEC("schedcls/egress4/snat4")
-int sched_cls_egress4_snat4_prog(struct __sk_buff *skb)
-{
- const int l2_header_size = sizeof(struct ethhdr);
- void *data = (void *)(long)skb->data;
- const void *data_end = (void *)(long)skb->data_end;
- const struct ethhdr *const eth = data; // used iff is_ethernet
- const struct iphdr *const ip4 = (void *)(eth + 1);
-
- // Must be meta-ethernet IPv4 frame
- if (skb->protocol != bpf_htons(ETH_P_IP))
- return TC_ACT_OK;
-
- // Must have ipv4 header
- if (data + l2_header_size + sizeof(struct ipv6hdr) > data_end)
- return TC_ACT_OK;
-
- // Ethertype - if present - must be IPv4
- if (eth->h_proto != bpf_htons(ETH_P_IP))
- return TC_ACT_OK;
-
- // IP version must be 4
- if (ip4->version != 4)
- return TC_ACT_OK;
-
- // We cannot handle IP options, just standard 20 byte == 5 dword minimal IPv4 header
- if (ip4->ihl != 5)
- return TC_ACT_OK;
-
- // Maximum IPv6 payload length that can be translated to IPv4
- if (bpf_htons(ip4->tot_len) > 0xFFFF - sizeof(struct ipv6hdr))
- return TC_ACT_OK;
-
- // Calculate the IPv4 one's complement checksum of the IPv4 header.
- __wsum sum4 = 0;
-
- for (int i = 0; i < sizeof(*ip4) / sizeof(__u16); ++i)
- sum4 += ((__u16 *)ip4)[i];
-
- // Note that sum4 is guaranteed to be non-zero by virtue of ip4->version == 4
- sum4 = (sum4 & 0xFFFF) + (sum4 >> 16); // collapse u32 into range 1 .. 0x1FFFE
- sum4 = (sum4 & 0xFFFF) + (sum4 >> 16); // collapse any potential carry into u16
- // for a correct checksum we should get *a* zero, but sum4 must be positive, ie 0xFFFF
- if (sum4 != 0xFFFF)
- return TC_ACT_OK;
-
- // Minimum IPv4 total length is the size of the header
- if (bpf_ntohs(ip4->tot_len) < sizeof(*ip4))
- return TC_ACT_OK;
-
- // We are incapable of dealing with IPv4 fragments
- if (ip4->frag_off & ~bpf_htons(IP_DF))
- return TC_ACT_OK;
-
- switch (ip4->protocol) {
- case IPPROTO_TCP: // For TCP & UDP the checksum neutrality of the chosen IPv6
- case IPPROTO_GRE: // address means there is no need to update their checksums.
- case IPPROTO_ESP: // We do not need to bother looking at GRE/ESP headers,
- break; // since there is never a checksum to update.
-
- case IPPROTO_UDP: // See above comment, but must also have UDP header...
- if (data + sizeof(*ip4) + sizeof(struct udphdr) > data_end)
- return TC_ACT_OK;
- const struct udphdr *uh = (const struct udphdr *)(ip4 + 1);
- // If IPv4/UDP checksum is 0 then fallback to clatd so it can calculate the
- // checksum. Otherwise the network or more likely the NAT64 gateway might
- // drop the packet because in most cases IPv6/UDP packets with a zero checksum
- // are invalid. See RFC 6935. TODO: calculate checksum via bpf_csum_diff()
- if (!uh->check)
- return TC_ACT_OK;
- break;
-
- default: // do not know how to handle anything else
- return TC_ACT_OK;
- }
- struct ethhdr eth2; // used iff is_ethernet
-
- eth2 = *eth; // Copy over the ethernet header (src/dst mac)
- eth2.h_proto = bpf_htons(ETH_P_IPV6); // But replace the ethertype
-
- struct ipv6hdr ip6 = {
- .version = 6, // __u8:4
- .priority = ip4->tos >> 4, // __u8:4
- .flow_lbl = {(ip4->tos & 0xF) << 4, 0, 0}, // __u8[3]
- .payload_len = bpf_htons(bpf_ntohs(ip4->tot_len) - 20), // __be16
- .nexthdr = ip4->protocol, // __u8
- .hop_limit = ip4->ttl, // __u8
- };
- ip6.saddr.in6_u.u6_addr32[0] = bpf_htonl(0x20010db8);
- ip6.saddr.in6_u.u6_addr32[1] = 0;
- ip6.saddr.in6_u.u6_addr32[2] = 0;
- ip6.saddr.in6_u.u6_addr32[3] = bpf_htonl(1);
- ip6.daddr.in6_u.u6_addr32[0] = bpf_htonl(0x20010db8);
- ip6.daddr.in6_u.u6_addr32[1] = 0;
- ip6.daddr.in6_u.u6_addr32[2] = 0;
- ip6.daddr.in6_u.u6_addr32[3] = bpf_htonl(2);
-
- // Calculate the IPv6 16-bit one's complement checksum of the IPv6 header.
- __wsum sum6 = 0;
- // We'll end up with a non-zero sum due to ip6.version == 6
- for (int i = 0; i < sizeof(ip6) / sizeof(__u16); ++i)
- sum6 += ((__u16 *)&ip6)[i];
-
- // Packet mutations begin - point of no return, but if this first modification fails
- // the packet is probably still pristine, so let clatd handle it.
- if (bpf_skb_change_proto(skb, bpf_htons(ETH_P_IPV6), 0))
- return TC_ACT_OK;
-
- // This takes care of updating the skb->csum field for a CHECKSUM_COMPLETE packet.
- // In such a case, skb->csum is a 16-bit one's complement sum of the entire payload,
- // thus we need to subtract out the ipv4 header's sum, and add in the ipv6 header's sum.
- // However, we've already verified the ipv4 checksum is correct and thus 0.
- // Thus we only need to add the ipv6 header's sum.
- //
- // bpf_csum_update() always succeeds if the skb is CHECKSUM_COMPLETE and returns an error
- // (-ENOTSUPP) if it isn't. So we just ignore the return code (see above for more details).
- bpf_csum_update(skb, sum6);
-
- // bpf_skb_change_proto() invalidates all pointers - reload them.
- data = (void *)(long)skb->data;
- data_end = (void *)(long)skb->data_end;
-
- // I cannot think of any valid way for this error condition to trigger, however I do
- // believe the explicit check is required to keep the in kernel ebpf verifier happy.
- if (data + l2_header_size + sizeof(ip6) > data_end)
- return TC_ACT_SHOT;
-
- struct ethhdr *new_eth = data;
-
- // Copy over the updated ethernet header
- *new_eth = eth2;
- // Copy over the new ipv4 header.
- *(struct ipv6hdr *)(new_eth + 1) = ip6;
- return TC_ACT_OK;
-}
-
-char _license[] SEC("license") = ("GPL");
diff --git a/tools/testing/selftests/net/udpgro.sh b/tools/testing/selftests/net/udpgro.sh
index 8802604148dda..11a1ebda564fd 100755
--- a/tools/testing/selftests/net/udpgro.sh
+++ b/tools/testing/selftests/net/udpgro.sh
@@ -7,7 +7,7 @@ source net_helper.sh
readonly PEER_NS="ns-peer-$(mktemp -u XXXXXX)"
-BPF_FILE="xdp_dummy.o"
+BPF_FILE="xdp_dummy.bpf.o"
# set global exit status, but never reset nonzero one.
check_err()
diff --git a/tools/testing/selftests/net/udpgro_bench.sh b/tools/testing/selftests/net/udpgro_bench.sh
index 7080eae5312b2..c51ea90a1395f 100755
--- a/tools/testing/selftests/net/udpgro_bench.sh
+++ b/tools/testing/selftests/net/udpgro_bench.sh
@@ -7,7 +7,7 @@ source net_helper.sh
readonly PEER_NS="ns-peer-$(mktemp -u XXXXXX)"
-BPF_FILE="xdp_dummy.o"
+BPF_FILE="xdp_dummy.bpf.o"
cleanup() {
local -r jobs="$(jobs -p)"
diff --git a/tools/testing/selftests/net/udpgro_frglist.sh b/tools/testing/selftests/net/udpgro_frglist.sh
index e1ff645bd3d1c..17404f49cdb68 100755
--- a/tools/testing/selftests/net/udpgro_frglist.sh
+++ b/tools/testing/selftests/net/udpgro_frglist.sh
@@ -7,7 +7,7 @@ source net_helper.sh
readonly PEER_NS="ns-peer-$(mktemp -u XXXXXX)"
-BPF_FILE="xdp_dummy.o"
+BPF_FILE="xdp_dummy.bpf.o"
cleanup() {
local -r jobs="$(jobs -p)"
@@ -42,8 +42,8 @@ run_one() {
ip -n "${PEER_NS}" link set veth1 xdp object ${BPF_FILE} section xdp
tc -n "${PEER_NS}" qdisc add dev veth1 clsact
- tc -n "${PEER_NS}" filter add dev veth1 ingress prio 4 protocol ipv6 bpf object-file nat6to4.o section schedcls/ingress6/nat_6 direct-action
- tc -n "${PEER_NS}" filter add dev veth1 egress prio 4 protocol ip bpf object-file nat6to4.o section schedcls/egress4/snat4 direct-action
+ tc -n "${PEER_NS}" filter add dev veth1 ingress prio 4 protocol ipv6 bpf object-file nat6to4.bpf.o section schedcls/ingress6/nat_6 direct-action
+ tc -n "${PEER_NS}" filter add dev veth1 egress prio 4 protocol ip bpf object-file nat6to4.bpf.o section schedcls/egress4/snat4 direct-action
echo ${rx_args}
ip netns exec "${PEER_NS}" ./udpgso_bench_rx ${rx_args} -r &
@@ -89,7 +89,7 @@ if [ ! -f ${BPF_FILE} ]; then
exit -1
fi
-if [ ! -f nat6to4.o ]; then
+if [ ! -f nat6to4.bpf.o ]; then
echo "Missing nat6to4 helper. Run 'make' first"
exit -1
fi
diff --git a/tools/testing/selftests/net/udpgro_fwd.sh b/tools/testing/selftests/net/udpgro_fwd.sh
index 83ed987cff340..550d8eb3e224c 100755
--- a/tools/testing/selftests/net/udpgro_fwd.sh
+++ b/tools/testing/selftests/net/udpgro_fwd.sh
@@ -3,7 +3,7 @@
source net_helper.sh
-BPF_FILE="xdp_dummy.o"
+BPF_FILE="xdp_dummy.bpf.o"
readonly BASE="ns-$(mktemp -u XXXXXX)"
readonly SRC=2
readonly DST=1
diff --git a/tools/testing/selftests/net/veth.sh b/tools/testing/selftests/net/veth.sh
index 3a394b43e274b..4f1edbafb9468 100755
--- a/tools/testing/selftests/net/veth.sh
+++ b/tools/testing/selftests/net/veth.sh
@@ -1,7 +1,7 @@
#!/bin/sh
# SPDX-License-Identifier: GPL-2.0
-BPF_FILE="xdp_dummy.o"
+BPF_FILE="xdp_dummy.bpf.o"
readonly STATS="$(mktemp -p /tmp ns-XXXXXX)"
readonly BASE=`basename $STATS`
readonly SRC=2
diff --git a/tools/testing/selftests/net/xdp_dummy.bpf.c b/tools/testing/selftests/net/xdp_dummy.bpf.c
new file mode 100644
index 0000000000000..d988b2e0cee84
--- /dev/null
+++ b/tools/testing/selftests/net/xdp_dummy.bpf.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#define KBUILD_MODNAME "xdp_dummy"
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+SEC("xdp")
+int xdp_dummy_prog(struct xdp_md *ctx)
+{
+ return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/net/xdp_dummy.c b/tools/testing/selftests/net/xdp_dummy.c
deleted file mode 100644
index d988b2e0cee84..0000000000000
--- a/tools/testing/selftests/net/xdp_dummy.c
+++ /dev/null
@@ -1,13 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-#define KBUILD_MODNAME "xdp_dummy"
-#include <linux/bpf.h>
-#include <bpf/bpf_helpers.h>
-
-SEC("xdp")
-int xdp_dummy_prog(struct xdp_md *ctx)
-{
- return XDP_PASS;
-}
-
-char _license[] SEC("license") = "GPL";