47 lines
943 B
C
47 lines
943 B
C
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// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2022 Huawei Technologies Duesseldorf GmbH
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*
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* Author: Roberto Sassu <roberto.sassu@huawei.com>
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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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char _license[] SEC("license") = "GPL";
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__u32 monitored_pid;
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__u32 key_serial;
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__u32 key_id;
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__u64 flags;
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extern struct bpf_key *bpf_lookup_user_key(__u32 serial, __u64 flags) __ksym;
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extern struct bpf_key *bpf_lookup_system_key(__u64 id) __ksym;
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extern void bpf_key_put(struct bpf_key *key) __ksym;
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SEC("lsm.s/bpf")
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int BPF_PROG(bpf, int cmd, union bpf_attr *attr, unsigned int size)
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{
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struct bpf_key *bkey;
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__u32 pid;
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pid = bpf_get_current_pid_tgid() >> 32;
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if (pid != monitored_pid)
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return 0;
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if (key_serial)
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bkey = bpf_lookup_user_key(key_serial, flags);
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else
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bkey = bpf_lookup_system_key(key_id);
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if (!bkey)
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return -ENOENT;
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bpf_key_put(bkey);
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return 0;
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}
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