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1// SPDX-License-Identifier: GPL-2.02 3#include <linux/stddef.h>4#include <linux/bpf.h>5#include <linux/in.h>6#include <sys/socket.h>7 8#include <bpf/bpf_helpers.h>9#include <bpf/bpf_endian.h>10 11#include <bpf_sockopt_helpers.h>12 13#define SERV4_IP 0xc0a801feU /* 192.168.1.254 */14#define SERV4_PORT 404015 16SEC("cgroup/recvmsg4")17int recvmsg4_prog(struct bpf_sock_addr *ctx)18{19 struct bpf_sock *sk;20 21 sk = ctx->sk;22 if (!sk)23 return 1;24 25 if (sk->family != AF_INET)26 return 1;27 28 if (ctx->type != SOCK_STREAM && ctx->type != SOCK_DGRAM)29 return 1;30 31 if (!get_set_sk_priority(ctx))32 return 1;33 34 ctx->user_ip4 = bpf_htonl(SERV4_IP);35 ctx->user_port = bpf_htons(SERV4_PORT);36 37 return 1;38}39 40char _license[] SEC("license") = "GPL";41