46 lines
		
	
	
		
			830 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			46 lines
		
	
	
		
			830 B
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| 
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| /*
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|  * Copyright 2020 Google LLC.
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|  */
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| 
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| #include "vmlinux.h"
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| #include <errno.h>
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| #include <bpf/bpf_helpers.h>
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| #include <bpf/bpf_tracing.h>
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| 
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| u32 monitored_pid = 0;
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| 
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| struct {
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| 	__uint(type, BPF_MAP_TYPE_RINGBUF);
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| 	__uint(max_entries, 1 << 12);
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| } ringbuf SEC(".maps");
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| 
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| char _license[] SEC("license") = "GPL";
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| 
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| SEC("lsm.s/bprm_committed_creds")
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| void BPF_PROG(ima, struct linux_binprm *bprm)
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| {
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| 	u64 ima_hash = 0;
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| 	u64 *sample;
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| 	int ret;
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| 	u32 pid;
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| 
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| 	pid = bpf_get_current_pid_tgid() >> 32;
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| 	if (pid == monitored_pid) {
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| 		ret = bpf_ima_inode_hash(bprm->file->f_inode, &ima_hash,
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| 					 sizeof(ima_hash));
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| 		if (ret < 0 || ima_hash == 0)
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| 			return;
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| 
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| 		sample = bpf_ringbuf_reserve(&ringbuf, sizeof(u64), 0);
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| 		if (!sample)
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| 			return;
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| 
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| 		*sample = ima_hash;
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| 		bpf_ringbuf_submit(sample, 0);
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| 	}
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| 
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| 	return;
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| }
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