/* Copyright (c) 2016 Sargun Dhillon <sargun@sargun.me>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of version 2 of the GNU General Public
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* License as published by the Free Software Foundation.
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*/
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#define _GNU_SOURCE
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#include <stdio.h>
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#include <linux/bpf.h>
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#include <unistd.h>
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#include <bpf/bpf.h>
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#include "bpf_load.h"
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#include <linux/bpf.h>
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#include "cgroup_helpers.h"
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#define CGROUP_PATH "/my-cgroup"
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int main(int argc, char **argv)
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{
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pid_t remote_pid, local_pid = getpid();
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int cg2, idx = 0, rc = 0;
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char filename[256];
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snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
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if (load_bpf_file(filename)) {
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printf("%s", bpf_log_buf);
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return 1;
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}
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if (setup_cgroup_environment())
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goto err;
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cg2 = create_and_get_cgroup(CGROUP_PATH);
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if (!cg2)
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goto err;
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if (bpf_map_update_elem(map_fd[0], &idx, &cg2, BPF_ANY)) {
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log_err("Adding target cgroup to map");
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goto err;
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}
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if (join_cgroup(CGROUP_PATH))
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goto err;
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/*
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* The installed helper program catched the sync call, and should
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* write it to the map.
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*/
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sync();
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bpf_map_lookup_elem(map_fd[1], &idx, &remote_pid);
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if (local_pid != remote_pid) {
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fprintf(stderr,
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"BPF Helper didn't write correct PID to map, but: %d\n",
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remote_pid);
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goto err;
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}
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/* Verify the negative scenario; leave the cgroup */
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if (join_cgroup("/"))
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goto err;
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remote_pid = 0;
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bpf_map_update_elem(map_fd[1], &idx, &remote_pid, BPF_ANY);
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sync();
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bpf_map_lookup_elem(map_fd[1], &idx, &remote_pid);
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if (local_pid == remote_pid) {
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fprintf(stderr, "BPF cgroup negative test did not work\n");
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goto err;
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}
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goto out;
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err:
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rc = 1;
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out:
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close(cg2);
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cleanup_cgroup_environment();
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return rc;
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}
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