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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /tools/testing/selftests/bpf/progs/test_tc_neigh.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/bpf/progs/test_tc_neigh.c')
-rw-r--r-- | tools/testing/selftests/bpf/progs/test_tc_neigh.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_tc_neigh.c b/tools/testing/selftests/bpf/progs/test_tc_neigh.c new file mode 100644 index 000000000..b985ac4e7 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_tc_neigh.c @@ -0,0 +1,149 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <stddef.h> +#include <stdint.h> +#include <stdbool.h> + +#include <linux/bpf.h> +#include <linux/stddef.h> +#include <linux/pkt_cls.h> +#include <linux/if_ether.h> +#include <linux/in.h> +#include <linux/ip.h> +#include <linux/ipv6.h> + +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_endian.h> + +#ifndef ctx_ptr +# define ctx_ptr(field) (void *)(long)(field) +#endif + +#define ip4_src 0xac100164 /* 172.16.1.100 */ +#define ip4_dst 0xac100264 /* 172.16.2.100 */ + +#define ip6_src { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \ + 0x00, 0x01, 0xde, 0xad, 0xbe, 0xef, 0xca, 0xfe } +#define ip6_dst { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \ + 0x00, 0x02, 0xde, 0xad, 0xbe, 0xef, 0xca, 0xfe } + +#ifndef v6_equal +# define v6_equal(a, b) (a.s6_addr32[0] == b.s6_addr32[0] && \ + a.s6_addr32[1] == b.s6_addr32[1] && \ + a.s6_addr32[2] == b.s6_addr32[2] && \ + a.s6_addr32[3] == b.s6_addr32[3]) +#endif + +enum { + dev_src, + dev_dst, +}; + +struct bpf_map_def SEC("maps") ifindex_map = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(int), + .value_size = sizeof(int), + .max_entries = 2, +}; + +static __always_inline bool is_remote_ep_v4(struct __sk_buff *skb, + __be32 addr) +{ + void *data_end = ctx_ptr(skb->data_end); + void *data = ctx_ptr(skb->data); + struct iphdr *ip4h; + + if (data + sizeof(struct ethhdr) > data_end) + return false; + + ip4h = (struct iphdr *)(data + sizeof(struct ethhdr)); + if ((void *)(ip4h + 1) > data_end) + return false; + + return ip4h->daddr == addr; +} + +static __always_inline bool is_remote_ep_v6(struct __sk_buff *skb, + struct in6_addr addr) +{ + void *data_end = ctx_ptr(skb->data_end); + void *data = ctx_ptr(skb->data); + struct ipv6hdr *ip6h; + + if (data + sizeof(struct ethhdr) > data_end) + return false; + + ip6h = (struct ipv6hdr *)(data + sizeof(struct ethhdr)); + if ((void *)(ip6h + 1) > data_end) + return false; + + return v6_equal(ip6h->daddr, addr); +} + +static __always_inline int get_dev_ifindex(int which) +{ + int *ifindex = bpf_map_lookup_elem(&ifindex_map, &which); + + return ifindex ? *ifindex : 0; +} + +SEC("chk_egress") int tc_chk(struct __sk_buff *skb) +{ + void *data_end = ctx_ptr(skb->data_end); + void *data = ctx_ptr(skb->data); + __u32 *raw = data; + + if (data + sizeof(struct ethhdr) > data_end) + return TC_ACT_SHOT; + + return !raw[0] && !raw[1] && !raw[2] ? TC_ACT_SHOT : TC_ACT_OK; +} + +SEC("dst_ingress") int tc_dst(struct __sk_buff *skb) +{ + __u8 zero[ETH_ALEN * 2]; + bool redirect = false; + + switch (skb->protocol) { + case __bpf_constant_htons(ETH_P_IP): + redirect = is_remote_ep_v4(skb, __bpf_constant_htonl(ip4_src)); + break; + case __bpf_constant_htons(ETH_P_IPV6): + redirect = is_remote_ep_v6(skb, (struct in6_addr)ip6_src); + break; + } + + if (!redirect) + return TC_ACT_OK; + + __builtin_memset(&zero, 0, sizeof(zero)); + if (bpf_skb_store_bytes(skb, 0, &zero, sizeof(zero), 0) < 0) + return TC_ACT_SHOT; + + return bpf_redirect_neigh(get_dev_ifindex(dev_src), NULL, 0, 0); +} + +SEC("src_ingress") int tc_src(struct __sk_buff *skb) +{ + __u8 zero[ETH_ALEN * 2]; + bool redirect = false; + + switch (skb->protocol) { + case __bpf_constant_htons(ETH_P_IP): + redirect = is_remote_ep_v4(skb, __bpf_constant_htonl(ip4_dst)); + break; + case __bpf_constant_htons(ETH_P_IPV6): + redirect = is_remote_ep_v6(skb, (struct in6_addr)ip6_dst); + break; + } + + if (!redirect) + return TC_ACT_OK; + + __builtin_memset(&zero, 0, sizeof(zero)); + if (bpf_skb_store_bytes(skb, 0, &zero, sizeof(zero), 0) < 0) + return TC_ACT_SHOT; + + return bpf_redirect_neigh(get_dev_ifindex(dev_dst), NULL, 0, 0); +} + +char __license[] SEC("license") = "GPL"; |