43 lines
758 B
C
43 lines
758 B
C
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// SPDX-License-Identifier: GPL-2.0
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#include <linux/stddef.h>
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#include <linux/bpf.h>
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#include <linux/in.h>
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#include <sys/socket.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_endian.h>
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#include <bpf_sockopt_helpers.h>
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#define SERV4_IP 0xc0a801feU /* 192.168.1.254 */
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#define SERV4_PORT 4040
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SEC("cgroup/recvmsg4")
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int recvmsg4_prog(struct bpf_sock_addr *ctx)
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{
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struct bpf_sock *sk;
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__u32 user_ip4;
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__u16 user_port;
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sk = ctx->sk;
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if (!sk)
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return 1;
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if (sk->family != AF_INET)
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return 1;
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if (ctx->type != SOCK_STREAM && ctx->type != SOCK_DGRAM)
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return 1;
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if (!get_set_sk_priority(ctx))
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return 1;
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ctx->user_ip4 = bpf_htonl(SERV4_IP);
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ctx->user_port = bpf_htons(SERV4_PORT);
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return 1;
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}
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char _license[] SEC("license") = "GPL";
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