/* SPDX-License-Identifier: MIT */

/*

 * Description: test if personalities work

 *

 */

#include <errno.h>

#include <stdio.h>

#include <unistd.h>

#include <stdlib.h>

#include <string.h>

#include <fcntl.h>

#include "liburing.h"

#define FNAME	"/tmp/.tmp.access"

#define USE_UID	1000

static int no_personality;

static int open_file(struct io_uring *ring, int cred_id, int with_link)

{

	struct io_uring_cqe *cqe;

	struct io_uring_sqe *sqe;

	int ret, i, to_submit = 1;

	if (with_link) {

		sqe = io_uring_get_sqe(ring);

		io_uring_prep_nop(sqe);

		sqe->flags |= IOSQE_IO_LINK;

		sqe->user_data = 1;

		to_submit++;

	}

	sqe = io_uring_get_sqe(ring);

	io_uring_prep_openat(sqe, -1, FNAME, O_RDONLY, 0);

	sqe->user_data = 2;

	if (cred_id != -1)

		sqe->personality = cred_id;

	ret = io_uring_submit(ring);

	if (ret != to_submit) {

		fprintf(stderr, "submit got: %d\n", ret);

		goto err;

	}

	for (i = 0; i < to_submit; i++) {

		ret = io_uring_wait_cqe(ring, &cqe);

		if (ret < 0) {

			fprintf(stderr, "wait completion %d\n", ret);

			goto err;

		}

		ret = cqe->res;

		io_uring_cqe_seen(ring, cqe);

	}

err:

	return ret;

}

static int test_personality(struct io_uring *ring)

{

	int ret, cred_id;

	ret = io_uring_register_personality(ring);

	if (ret < 0) {

		if (ret == -EINVAL) {

			fprintf(stdout, "Personalities not supported, skipping\n");

			no_personality = 1;

			goto out;

		}

		fprintf(stderr, "register_personality: %d\n", ret);

		goto err;

	}

	cred_id = ret;

	/* create file only owner can open */

	ret = open(FNAME, O_RDONLY | O_CREAT, 0600);

	if (ret < 0) {

		perror("open");

		goto err;

	}

	close(ret);

	/* verify we can open it */

	ret = open_file(ring, -1, 0);

	if (ret < 0) {

		fprintf(stderr, "current open got: %d\n", ret);

		goto err;

	}

	if (seteuid(USE_UID) < 0) {

		fprintf(stdout, "Can't switch to UID %u, skipping\n", USE_UID);

		goto out;

	}

	/* verify we can't open it with current credentials */

	ret = open_file(ring, -1, 0);

	if (ret != -EACCES) {

		fprintf(stderr, "open got: %d\n", ret);

		goto err;

	}

	/* verify we can open with registered credentials */

	ret = open_file(ring, cred_id, 0);

	if (ret < 0) {

		fprintf(stderr, "credential open: %d\n", ret);

		goto err;

	}

	close(ret);

	/* verify we can open with registered credentials and as a link */

	ret = open_file(ring, cred_id, 1);

	if (ret < 0) {

		fprintf(stderr, "credential open: %d\n", ret);

		goto err;

	}

	if (seteuid(0))

		perror("seteuid");

	ret = io_uring_unregister_personality(ring, cred_id);

	if (ret) {

		fprintf(stderr, "register_personality: %d\n", ret);

		goto err;

	}

out:

	unlink(FNAME);

	return 0;

err:

	unlink(FNAME);

	return 1;

}

static int test_invalid_personality(struct io_uring *ring)

{

	int ret;

	ret = open_file(ring, 2, 0);

	if (ret != -EINVAL) {

		fprintf(stderr, "invalid personality got: %d\n", ret);

		goto err;

	}

	return 0;

err:

	return 1;

}

static int test_invalid_unregister(struct io_uring *ring)

{

	int ret;

	ret = io_uring_unregister_personality(ring, 2);

	if (ret != -EINVAL) {

		fprintf(stderr, "invalid personality unregister got: %d\n", ret);

		goto err;

	}

	return 0;

err:

	return 1;

}

int main(int argc, char *argv[])

{

	struct io_uring ring;

	int ret;

	if (argc > 1)

		return 0;

	if (geteuid()) {

		fprintf(stderr, "Not root, skipping\n");

		return 0;

	}

	ret = io_uring_queue_init(8, &ring, 0);

	if (ret) {

		fprintf(stderr, "ring setup failed: %d\n", ret);

		return 1;

	}

	ret = test_personality(&ring);

	if (ret) {

		fprintf(stderr, "test_personality failed\n");

		return ret;

	}

	if (no_personality)

		return 0;

	ret = test_invalid_personality(&ring);

	if (ret) {

		fprintf(stderr, "test_invalid_personality failed\n");

		return ret;

	}

	ret = test_invalid_unregister(&ring);

	if (ret) {

		fprintf(stderr, "test_invalid_unregister failed\n");

		return ret;

	}

	return 0;

}