94 lines
2.2 KiB
C
94 lines
2.2 KiB
C
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// SPDX-License-Identifier: GPL-2.0-only
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/* Copyright (c) 2017 Facebook
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <errno.h>
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#include <assert.h>
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#include <sys/time.h>
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#include <linux/bpf.h>
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#include <bpf/bpf.h>
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#include <bpf/libbpf.h>
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#include "cgroup_helpers.h"
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#include "bpf_rlimit.h"
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#define DEV_CGROUP_PROG "./dev_cgroup.o"
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#define TEST_CGROUP "/test-bpf-based-device-cgroup/"
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int main(int argc, char **argv)
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{
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struct bpf_object *obj;
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int error = EXIT_FAILURE;
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int prog_fd, cgroup_fd;
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__u32 prog_cnt;
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if (bpf_prog_load(DEV_CGROUP_PROG, BPF_PROG_TYPE_CGROUP_DEVICE,
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&obj, &prog_fd)) {
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printf("Failed to load DEV_CGROUP program\n");
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goto out;
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}
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if (setup_cgroup_environment()) {
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printf("Failed to load DEV_CGROUP program\n");
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goto err;
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}
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/* Create a cgroup, get fd, and join it */
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cgroup_fd = create_and_get_cgroup(TEST_CGROUP);
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if (cgroup_fd < 0) {
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printf("Failed to create test cgroup\n");
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goto err;
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}
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if (join_cgroup(TEST_CGROUP)) {
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printf("Failed to join cgroup\n");
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goto err;
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}
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/* Attach bpf program */
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if (bpf_prog_attach(prog_fd, cgroup_fd, BPF_CGROUP_DEVICE, 0)) {
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printf("Failed to attach DEV_CGROUP program");
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goto err;
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}
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if (bpf_prog_query(cgroup_fd, BPF_CGROUP_DEVICE, 0, NULL, NULL,
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&prog_cnt)) {
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printf("Failed to query attached programs");
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goto err;
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}
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/* All operations with /dev/zero and and /dev/urandom are allowed,
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* everything else is forbidden.
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*/
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assert(system("rm -f /tmp/test_dev_cgroup_null") == 0);
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assert(system("mknod /tmp/test_dev_cgroup_null c 1 3"));
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assert(system("rm -f /tmp/test_dev_cgroup_null") == 0);
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/* /dev/zero is whitelisted */
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assert(system("rm -f /tmp/test_dev_cgroup_zero") == 0);
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assert(system("mknod /tmp/test_dev_cgroup_zero c 1 5") == 0);
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assert(system("rm -f /tmp/test_dev_cgroup_zero") == 0);
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assert(system("dd if=/dev/urandom of=/dev/zero count=64") == 0);
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/* src is allowed, target is forbidden */
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assert(system("dd if=/dev/urandom of=/dev/full count=64"));
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/* src is forbidden, target is allowed */
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assert(system("dd if=/dev/random of=/dev/zero count=64"));
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error = 0;
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printf("test_dev_cgroup:PASS\n");
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err:
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cleanup_cgroup_environment();
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out:
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return error;
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}
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