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1// SPDX-License-Identifier: GPL-2.02// Copyright (c) 2018 Facebook3 4#include "vmlinux.h"5 6#include <bpf/bpf_helpers.h>7#include <bpf/bpf_endian.h>8#include <bpf/bpf_tracing.h>9 10#define AF_INET6 1011 12struct socket_cookie {13 __u64 cookie_key;14 __u32 cookie_value;15};16 17struct {18 __uint(type, BPF_MAP_TYPE_SK_STORAGE);19 __uint(map_flags, BPF_F_NO_PREALLOC);20 __type(key, int);21 __type(value, struct socket_cookie);22} socket_cookies SEC(".maps");23 24/*25 * These three programs get executed in a row on connect() syscalls. The26 * userspace side of the test creates a client socket, issues a connect() on it27 * and then checks that the local storage associated with this socket has:28 * cookie_value == local_port << 8 | 0xFF29 * The different parts of this cookie_value are appended by those hooks if they30 * all agree on the output of bpf_get_socket_cookie().31 */32SEC("cgroup/connect6")33int set_cookie(struct bpf_sock_addr *ctx)34{35 struct socket_cookie *p;36 37 if (ctx->family != AF_INET6 || ctx->user_family != AF_INET6)38 return 1;39 40 p = bpf_sk_storage_get(&socket_cookies, ctx->sk, 0,41 BPF_SK_STORAGE_GET_F_CREATE);42 if (!p)43 return 1;44 45 p->cookie_value = 0xF;46 p->cookie_key = bpf_get_socket_cookie(ctx);47 48 return 1;49}50 51SEC("sockops")52int update_cookie_sockops(struct bpf_sock_ops *ctx)53{54 struct bpf_sock *sk = ctx->sk;55 struct socket_cookie *p;56 57 if (ctx->family != AF_INET6)58 return 1;59 60 if (ctx->op != BPF_SOCK_OPS_TCP_CONNECT_CB)61 return 1;62 63 if (!sk)64 return 1;65 66 p = bpf_sk_storage_get(&socket_cookies, sk, 0, 0);67 if (!p)68 return 1;69 70 if (p->cookie_key != bpf_get_socket_cookie(ctx))71 return 1;72 73 p->cookie_value |= (ctx->local_port << 8);74 75 return 1;76}77 78SEC("fexit/inet_stream_connect")79int BPF_PROG(update_cookie_tracing, struct socket *sock,80 struct sockaddr *uaddr, int addr_len, int flags)81{82 struct socket_cookie *p;83 84 if (uaddr->sa_family != AF_INET6)85 return 0;86 87 p = bpf_sk_storage_get(&socket_cookies, sock->sk, 0, 0);88 if (!p)89 return 0;90 91 if (p->cookie_key != bpf_get_socket_cookie(sock->sk))92 return 0;93 94 p->cookie_value |= 0xF0;95 96 return 0;97}98 99char _license[] SEC("license") = "GPL";100