| 1 | // SPDX-License-Identifier: GPL-2.0 |
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| 2 | /* Copyright (c) 2023 Facebook */ |
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| 3 | #include "vmlinux.h" |
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| 4 | #include "bpf_tracing_net.h" |
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| 5 | #include <bpf/bpf_helpers.h> |
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| 6 | #include <bpf/bpf_tracing.h> |
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| 7 | #include <bpf/bpf_core_read.h> |
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| 8 | |
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| 9 | void *local_storage_ptr = NULL; |
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| 10 | void *sk_ptr = NULL; |
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| 11 | int cookie_found = 0; |
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| 12 | __u64 cookie = 0; |
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| 13 | __u32 omem = 0; |
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| 14 | |
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| 15 | struct { |
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| 16 | __uint(type, BPF_MAP_TYPE_SK_STORAGE); |
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| 17 | __uint(map_flags, BPF_F_NO_PREALLOC); |
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| 18 | __type(key, int); |
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| 19 | __type(value, int); |
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| 20 | } sk_storage SEC(".maps" ); |
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| 21 | |
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| 22 | SEC("fexit/bpf_local_storage_destroy" ) |
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| 23 | int BPF_PROG(bpf_local_storage_destroy, struct bpf_local_storage *local_storage) |
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| 24 | { |
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| 25 | struct sock *sk; |
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| 26 | |
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| 27 | if (local_storage_ptr != local_storage) |
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| 28 | return 0; |
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| 29 | |
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| 30 | sk = bpf_core_cast(sk_ptr, struct sock); |
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| 31 | if (sk->sk_cookie.counter != cookie) |
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| 32 | return 0; |
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| 33 | |
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| 34 | cookie_found++; |
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| 35 | omem = sk->sk_omem_alloc.counter; |
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| 36 | local_storage_ptr = NULL; |
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| 37 | |
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| 38 | return 0; |
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| 39 | } |
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| 40 | |
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| 41 | SEC("fentry/inet6_sock_destruct" ) |
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| 42 | int BPF_PROG(inet6_sock_destruct, struct sock *sk) |
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| 43 | { |
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| 44 | int *value; |
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| 45 | |
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| 46 | if (!cookie || sk->sk_cookie.counter != cookie) |
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| 47 | return 0; |
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| 48 | |
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| 49 | value = bpf_sk_storage_get(&sk_storage, sk, 0, 0); |
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| 50 | if (value && *value == 0xdeadbeef) { |
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| 51 | cookie_found++; |
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| 52 | sk_ptr = sk; |
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| 53 | local_storage_ptr = sk->sk_bpf_storage; |
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| 54 | } |
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| 55 | |
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| 56 | return 0; |
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| 57 | } |
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| 58 | |
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| 59 | char _license[] SEC("license" ) = "GPL" ; |
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| 60 | |
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