71 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			71 lines
		
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| // Copyright (c) 2020 Isovalent, Inc.
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| #include "vmlinux.h"
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| #include <bpf/bpf_helpers.h>
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| 
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| struct {
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| 	__uint(type, BPF_MAP_TYPE_SOCKMAP);
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| 	__uint(max_entries, 2);
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| 	__type(key, __u32);
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| 	__type(value, __u64);
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| } sock_map SEC(".maps");
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| 
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| struct {
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| 	__uint(type, BPF_MAP_TYPE_SOCKHASH);
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| 	__uint(max_entries, 2);
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| 	__type(key, __u32);
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| 	__type(value, __u64);
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| } sock_hash SEC(".maps");
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| 
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| struct {
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| 	__uint(type, BPF_MAP_TYPE_SK_STORAGE);
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| 	__uint(map_flags, BPF_F_NO_PREALLOC);
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| 	__type(key, __u32);
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| 	__type(value, __u64);
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| } socket_storage SEC(".maps");
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| 
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| static int prog_msg_verdict_common(struct sk_msg_md *msg)
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| {
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| 	struct task_struct *task = (struct task_struct *)bpf_get_current_task();
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| 	int verdict = SK_PASS;
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| 	__u32 pid, tpid;
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| 	__u64 *sk_stg;
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| 
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| 	pid = bpf_get_current_pid_tgid() >> 32;
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| 	sk_stg = bpf_sk_storage_get(&socket_storage, msg->sk, 0, BPF_SK_STORAGE_GET_F_CREATE);
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| 	if (!sk_stg)
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| 		return SK_DROP;
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| 	*sk_stg = pid;
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| 	bpf_probe_read_kernel(&tpid , sizeof(tpid), &task->tgid);
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| 	if (pid != tpid)
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| 		verdict = SK_DROP;
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| 	bpf_sk_storage_delete(&socket_storage, (void *)msg->sk);
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| 	return verdict;
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| }
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| 
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| SEC("sk_msg")
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| int prog_msg_verdict(struct sk_msg_md *msg)
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| {
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| 	return prog_msg_verdict_common(msg);
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| }
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| 
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| SEC("sk_msg")
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| int prog_msg_verdict_clone(struct sk_msg_md *msg)
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| {
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| 	return prog_msg_verdict_common(msg);
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| }
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| 
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| SEC("sk_msg")
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| int prog_msg_verdict_clone2(struct sk_msg_md *msg)
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| {
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| 	return prog_msg_verdict_common(msg);
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| }
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| 
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| SEC("sk_skb/stream_verdict")
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| int prog_skb_verdict(struct __sk_buff *skb)
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| {
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| 	return SK_PASS;
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| }
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| 
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| char _license[] SEC("license") = "GPL";
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