diff options
Diffstat (limited to 'tools/testing/selftests/net/bpf')
| -rw-r--r-- | tools/testing/selftests/net/bpf/Makefile | 51 | ||||
| -rw-r--r-- | tools/testing/selftests/net/bpf/nat6to4.c | 285 |
2 files changed, 0 insertions, 336 deletions
diff --git a/tools/testing/selftests/net/bpf/Makefile b/tools/testing/selftests/net/bpf/Makefile deleted file mode 100644 index 4abaf16d2077..000000000000 --- a/tools/testing/selftests/net/bpf/Makefile +++ /dev/null @@ -1,51 +0,0 @@ -# SPDX-License-Identifier: GPL-2.0 - -CLANG ?= clang -SCRATCH_DIR := $(OUTPUT)/tools -BUILD_DIR := $(SCRATCH_DIR)/build -BPFDIR := $(abspath ../../../lib/bpf) -APIDIR := $(abspath ../../../include/uapi) - -CCINCLUDE += -I../../bpf -CCINCLUDE += -I../../../../../usr/include/ -CCINCLUDE += -I$(SCRATCH_DIR)/include - -BPFOBJ := $(BUILD_DIR)/libbpf/libbpf.a - -MAKE_DIRS := $(BUILD_DIR)/libbpf $(OUTPUT)/bpf -$(MAKE_DIRS): - mkdir -p $@ - -TEST_CUSTOM_PROGS = $(OUTPUT)/bpf/nat6to4.o -all: $(TEST_CUSTOM_PROGS) - -# Get Clang's default includes on this system, as opposed to those seen by -# '-target bpf'. This fixes "missing" files on some architectures/distros, -# such as asm/byteorder.h, asm/socket.h, asm/sockios.h, sys/cdefs.h etc. -# -# Use '-idirafter': Don't interfere with include mechanics except where the -# build would have failed anyways. -define get_sys_includes -$(shell $(1) $(2) -v -E - </dev/null 2>&1 \ - | sed -n '/<...> search starts here:/,/End of search list./{ s| \(/.*\)|-idirafter \1|p }') \ -$(shell $(1) $(2) -dM -E - </dev/null | grep '__riscv_xlen ' | awk '{printf("-D__riscv_xlen=%d -D__BITS_PER_LONG=%d", $$3, $$3)}') -endef - -ifneq ($(CROSS_COMPILE),) -CLANG_TARGET_ARCH = --target=$(notdir $(CROSS_COMPILE:%-=%)) -endif - -CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH)) - -$(TEST_CUSTOM_PROGS): $(OUTPUT)/%.o: %.c $(BPFOBJ) | $(MAKE_DIRS) - $(CLANG) -O2 -target bpf -c $< $(CCINCLUDE) $(CLANG_SYS_INCLUDES) -o $@ - -$(BPFOBJ): $(wildcard $(BPFDIR)/*.[ch] $(BPFDIR)/Makefile) \ - $(APIDIR)/linux/bpf.h \ - | $(BUILD_DIR)/libbpf - $(MAKE) $(submake_extras) -C $(BPFDIR) OUTPUT=$(BUILD_DIR)/libbpf/ \ - EXTRA_CFLAGS='-g -O0' \ - DESTDIR=$(SCRATCH_DIR) prefix= all install_headers - -EXTRA_CLEAN := $(TEST_CUSTOM_PROGS) $(SCRATCH_DIR) - diff --git a/tools/testing/selftests/net/bpf/nat6to4.c b/tools/testing/selftests/net/bpf/nat6to4.c deleted file mode 100644 index ac54c36b25fc..000000000000 --- a/tools/testing/selftests/net/bpf/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"); |