1/*-
2 * Copyright (c) 2011 Google, Inc.
3 * Copyright (c) 2023-2024 Juniper Networks, Inc.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/types.h>
29#include <sys/disk.h>
30#include <sys/ioctl.h>
31#include <sys/stat.h>
32#include <dirent.h>
33#include <dlfcn.h>
34#include <err.h>
35#include <errno.h>
36#include <fcntl.h>
37#include <getopt.h>
38#include <inttypes.h>
39#include <libgen.h>
40#include <limits.h>
41#include <stdbool.h>
42#include <stdio.h>
43#include <stdlib.h>
44#include <string.h>
45#include <termios.h>
46#include <unistd.h>
47
48#include <userboot.h>
49
50char **vars;
51
52char *host_base = NULL;
53struct termios term, oldterm;
54char *image;
55size_t image_size;
56
57uint64_t regs[16];
58uint64_t pc;
59int *disk_fd;
60int disk_index = -1;
61
62void test_exit(void *arg, int v);
63
64/*
65 * Console i/o
66 */
67
68void
69test_putc(void *arg, int ch)
70{
71	char c = ch;
72
73	write(1, &c, 1);
74}
75
76int
77test_getc(void *arg)
78{
79	char c;
80
81	if (read(0, &c, 1) == 1)
82		return c;
83	return -1;
84}
85
86int
87test_poll(void *arg)
88{
89	int n;
90
91	if (ioctl(0, FIONREAD, &n) >= 0)
92		return (n > 0);
93	return (0);
94}
95
96/*
97 * Host filesystem i/o
98 */
99
100struct test_file {
101	int tf_isdir;
102	size_t tf_size;
103	struct stat tf_stat;
104	union {
105		int fd;
106		DIR *dir;
107	} tf_u;
108};
109
110static int
111test_open_internal(void *arg, const char *filename, void **h_return,
112    struct test_file *tf, int depth)
113{
114	char path[PATH_MAX];
115	char linkpath[PATH_MAX];
116	char *component, *cp, *linkptr;
117	ssize_t slen;
118	int comp_fd, dir_fd, error;
119	char c;
120	bool openbase;
121
122	if (depth++ >= MAXSYMLINKS)
123		return (ELOOP);
124
125	openbase = false;
126	error = EINVAL;
127	if (tf == NULL) {
128		tf = calloc(1, sizeof(struct test_file));
129		if (tf == NULL)
130			return (error);
131		openbase = true;
132	} else if (tf->tf_isdir) {
133		if (filename[0] == '/') {
134			closedir(tf->tf_u.dir);
135			openbase = true;
136		}
137	} else
138		return (error);
139
140	if (openbase) {
141		dir_fd = open(host_base, O_RDONLY);
142		if (dir_fd < 0)
143			goto out;
144
145		tf->tf_isdir = 1;
146		tf->tf_u.dir = fdopendir(dir_fd);
147
148		if (fstat(dir_fd, &tf->tf_stat) < 0) {
149			error = errno;
150			goto out;
151		}
152		tf->tf_size = tf->tf_stat.st_size;
153	}
154
155	strlcpy(path, filename, sizeof(path));
156	cp = path;
157	while (*cp) {
158		/*
159		 * The test file should be a directory at this point.
160		 * If it is not, then the caller provided an invalid filename.
161		 */
162		if (!tf->tf_isdir)
163			goto out;
164
165		/* Trim leading slashes */
166		while (*cp == '/')
167			cp++;
168
169		/* If we reached the end, we are done */
170		if (*cp == '\0')
171			break;
172
173		/* Get the file descriptor for the directory */
174		dir_fd = dirfd(tf->tf_u.dir);
175
176		/* Get the next component path */
177		component = cp;
178		while ((c = *cp) != '\0' && c != '/')
179			cp++;
180		if (c == '/')
181			*cp++ = '\0';
182
183		/* Get status of the component */
184		if (fstatat(dir_fd, component, &tf->tf_stat,
185		    AT_SYMLINK_NOFOLLOW) < 0) {
186			error = errno;
187			goto out;
188		}
189		tf->tf_size = tf->tf_stat.st_size;
190
191		/*
192		 * Check that the path component is a directory, regular file,
193		 * or a symlink.
194		 */
195		if (!S_ISDIR(tf->tf_stat.st_mode) &&
196		    !S_ISREG(tf->tf_stat.st_mode) &&
197		    !S_ISLNK(tf->tf_stat.st_mode))
198			goto out;
199
200		/* For anything that is not a symlink, open it */
201		if (!S_ISLNK(tf->tf_stat.st_mode)) {
202			comp_fd = openat(dir_fd, component, O_RDONLY);
203			if (comp_fd < 0)
204				goto out;
205		}
206
207		if (S_ISDIR(tf->tf_stat.st_mode)) {
208			/* Directory */
209
210			/* close the parent directory */
211			closedir(tf->tf_u.dir);
212
213			/* Open the directory from the component descriptor */
214			tf->tf_isdir = 1;
215			tf->tf_u.dir = fdopendir(comp_fd);
216			if (!tf->tf_u.dir)
217				goto out;
218		} else if (S_ISREG(tf->tf_stat.st_mode)) {
219			/* Regular file */
220
221			/* close the parent directory */
222			closedir(tf->tf_u.dir);
223
224			/* Stash the component descriptor */
225			tf->tf_isdir = 0;
226			tf->tf_u.fd = comp_fd;
227		} else if (S_ISLNK(tf->tf_stat.st_mode)) {
228			/* Symlink */
229
230			/* Read what the symlink points to */
231			slen = readlinkat(dir_fd, component, linkpath,
232			    sizeof(linkpath));
233			if (slen < 0)
234				goto out;
235			/* NUL-terminate the string */
236			linkpath[(size_t)slen] = '\0';
237
238			/* Open the thing that the symlink points to */
239			error = test_open_internal(arg, linkpath, NULL,
240			    tf, depth);
241			if (error != 0)
242				goto out;
243		}
244	}
245
246	/* Completed the entire path and have a good file/directory */
247	if (h_return != NULL)
248		*h_return = tf;
249	return (0);
250
251out:
252	/* Failure of some sort, clean up */
253	if (tf->tf_isdir)
254		closedir(tf->tf_u.dir);
255	else
256		close(tf->tf_u.fd);
257	free(tf);
258	return (error);
259}
260
261int
262test_open(void *arg, const char *filename, void **h_return)
263{
264	if (host_base == NULL)
265		return (ENOENT);
266
267	return (test_open_internal(arg, filename, h_return, NULL, 0));
268}
269
270int
271test_close(void *arg, void *h)
272{
273	struct test_file *tf = h;
274
275	if (tf->tf_isdir)
276		closedir(tf->tf_u.dir);
277	else
278		close(tf->tf_u.fd);
279	free(tf);
280
281	return (0);
282}
283
284int
285test_isdir(void *arg, void *h)
286{
287	struct test_file *tf = h;
288
289	return (tf->tf_isdir);
290}
291
292int
293test_read(void *arg, void *h, void *dst, size_t size, size_t *resid_return)
294{
295	struct test_file *tf = h;
296	ssize_t sz;
297
298	if (tf->tf_isdir)
299		return (EINVAL);
300	sz = read(tf->tf_u.fd, dst, size);
301	if (sz < 0)
302		return (EINVAL);
303	*resid_return = size - sz;
304	return (0);
305}
306
307int
308test_readdir(void *arg, void *h, uint32_t *fileno_return, uint8_t *type_return,
309    size_t *namelen_return, char *name)
310{
311	struct test_file *tf = h;
312	struct dirent *dp;
313
314	if (!tf->tf_isdir)
315		return (EINVAL);
316
317	dp = readdir(tf->tf_u.dir);
318	if (!dp)
319		return (ENOENT);
320
321	/*
322	 * Note: d_namlen is in the range 0..255 and therefore less
323	 * than PATH_MAX so we don't need to test before copying.
324	 */
325	*fileno_return = dp->d_fileno;
326	*type_return = dp->d_type;
327	*namelen_return = dp->d_namlen;
328	memcpy(name, dp->d_name, dp->d_namlen);
329	name[dp->d_namlen] = 0;
330
331	return (0);
332}
333
334int
335test_seek(void *arg, void *h, uint64_t offset, int whence)
336{
337	struct test_file *tf = h;
338
339	if (tf->tf_isdir)
340		return (EINVAL);
341	if (lseek(tf->tf_u.fd, offset, whence) < 0)
342		return (errno);
343	return (0);
344}
345
346int
347test_stat(void *arg, void *h, struct stat *stp)
348{
349	struct test_file *tf = h;
350
351	if (!stp)
352		return (-1);
353	memset(stp, 0, sizeof(struct stat));
354	stp->st_mode = tf->tf_stat.st_mode;
355	stp->st_uid = tf->tf_stat.st_uid;
356	stp->st_gid = tf->tf_stat.st_gid;
357	stp->st_size = tf->tf_stat.st_size;
358	stp->st_ino = tf->tf_stat.st_ino;
359	stp->st_dev = tf->tf_stat.st_dev;
360	stp->st_mtime = tf->tf_stat.st_mtime;
361	return (0);
362}
363
364/*
365 * Disk image i/o
366 */
367
368int
369test_diskread(void *arg, int unit, uint64_t offset, void *dst, size_t size,
370    size_t *resid_return)
371{
372	ssize_t n;
373
374	if (unit > disk_index || disk_fd[unit] == -1)
375		return (EIO);
376	n = pread(disk_fd[unit], dst, size, offset);
377	if (n == 0) {
378		printf("%s: end of disk (%ju)\n", __func__, (intmax_t)offset);
379		return (EIO);
380	}
381
382	if (n < 0)
383		return (errno);
384	*resid_return = size - n;
385	return (0);
386}
387
388int
389test_diskwrite(void *arg, int unit, uint64_t offset, void *src, size_t size,
390    size_t *resid_return)
391{
392	ssize_t n;
393
394	if (unit > disk_index || disk_fd[unit] == -1)
395		return (EIO);
396	n = pwrite(disk_fd[unit], src, size, offset);
397	if (n < 0)
398		return (errno);
399	*resid_return = size - n;
400	return (0);
401}
402
403int
404test_diskioctl(void *arg, int unit, u_long cmd, void *data)
405{
406	struct stat sb;
407
408	if (unit > disk_index || disk_fd[unit] == -1)
409		return (EBADF);
410	switch (cmd) {
411	case DIOCGSECTORSIZE:
412		*(u_int *)data = 512;
413		break;
414	case DIOCGMEDIASIZE:
415		if (fstat(disk_fd[unit], &sb) == 0)
416			*(off_t *)data = sb.st_size;
417		else
418			return (ENOTTY);
419		break;
420	default:
421		return (ENOTTY);
422	}
423	return (0);
424}
425
426/*
427 * Guest virtual machine i/o
428 *
429 * Note: guest addresses are kernel virtual
430 */
431
432int
433test_copyin(void *arg, const void *from, uint64_t to, size_t size)
434{
435
436	to &= 0x7fffffff;
437	if (to > image_size)
438		return (EFAULT);
439	if (to + size > image_size)
440		size = image_size - to;
441	memcpy(&image[to], from, size);
442	return(0);
443}
444
445int
446test_copyout(void *arg, uint64_t from, void *to, size_t size)
447{
448
449	from &= 0x7fffffff;
450	if (from > image_size)
451		return (EFAULT);
452	if (from + size > image_size)
453		size = image_size - from;
454	memcpy(to, &image[from], size);
455	return(0);
456}
457
458void
459test_setreg(void *arg, int r, uint64_t v)
460{
461
462	if (r < 0 || r >= 16)
463		return;
464	regs[r] = v;
465}
466
467void
468test_setmsr(void *arg, int r, uint64_t v)
469{
470}
471
472void
473test_setcr(void *arg, int r, uint64_t v)
474{
475}
476
477void
478test_setgdt(void *arg, uint64_t v, size_t sz)
479{
480}
481
482void
483test_exec(void *arg, uint64_t pc)
484{
485	printf("Execute at 0x%"PRIx64"\n", pc);
486	test_exit(arg, 0);
487}
488
489/*
490 * Misc
491 */
492
493void
494test_delay(void *arg, int usec)
495{
496
497	usleep(usec);
498}
499
500void
501test_exit(void *arg, int v)
502{
503
504	tcsetattr(0, TCSAFLUSH, &oldterm);
505	exit(v);
506}
507
508void
509test_getmem(void *arg, uint64_t *lowmem, uint64_t *highmem)
510{
511
512        *lowmem = 128*1024*1024;
513        *highmem = 0;
514}
515
516char *
517test_getenv(void *arg, int idx)
518{
519	static char *myvars[] = {
520		"USERBOOT=1"
521	};
522	static const int num_myvars = nitems(myvars);
523
524	if (idx < num_myvars)
525		return (myvars[idx]);
526	else
527		return (vars[idx - num_myvars]);
528}
529
530struct loader_callbacks cb = {
531	.putc = test_putc,
532	.getc = test_getc,
533	.poll = test_poll,
534
535	.open = test_open,
536	.close = test_close,
537	.isdir = test_isdir,
538	.read = test_read,
539	.readdir = test_readdir,
540	.seek = test_seek,
541	.stat = test_stat,
542
543	.diskread = test_diskread,
544	.diskwrite = test_diskwrite,
545	.diskioctl = test_diskioctl,
546
547	.copyin = test_copyin,
548	.copyout = test_copyout,
549	.setreg = test_setreg,
550	.setmsr = test_setmsr,
551	.setcr = test_setcr,
552        .setgdt = test_setgdt,
553	.exec = test_exec,
554
555	.delay = test_delay,
556	.exit = test_exit,
557        .getmem = test_getmem,
558
559	.getenv = test_getenv,
560};
561
562void
563usage()
564{
565
566	printf("usage: [-b <userboot shared object>] [-d <disk image path>] [-h <host filesystem path>\n");
567	exit(1);
568}
569
570int
571main(int argc, char** argv, char ** environment)
572{
573	void *h;
574	void (*func)(struct loader_callbacks *, void *, int, int) __dead2;
575	int opt;
576	const char *userboot_obj = "/boot/userboot.so";
577	int oflag = O_RDONLY;
578
579	vars = environment;
580
581	while ((opt = getopt(argc, argv, "wb:d:h:")) != -1) {
582		switch (opt) {
583		case 'b':
584			userboot_obj = optarg;
585			break;
586
587		case 'd':
588			disk_index++;
589			disk_fd = reallocarray(disk_fd, disk_index + 1,
590			    sizeof (int));
591			disk_fd[disk_index] = open(optarg, oflag);
592			if (disk_fd[disk_index] < 0)
593				err(1, "Can't open disk image '%s'", optarg);
594			break;
595
596		case 'h':
597			host_base = optarg;
598			break;
599
600		case 'w':
601			oflag = O_RDWR;
602			break;
603
604		case '?':
605			usage();
606		}
607	}
608
609	h = dlopen(userboot_obj, RTLD_LOCAL);
610	if (!h) {
611		printf("%s\n", dlerror());
612		return (1);
613	}
614	func = dlsym(h, "loader_main");
615	if (!func) {
616		printf("%s\n", dlerror());
617		return (1);
618	}
619
620	image_size = 128*1024*1024;
621	image = malloc(image_size);
622
623	tcgetattr(0, &term);
624	oldterm = term;
625	term.c_iflag &= ~(ICRNL);
626	term.c_lflag &= ~(ICANON|ECHO);
627	tcsetattr(0, TCSAFLUSH, &term);
628
629	func(&cb, NULL, USERBOOT_VERSION_3, disk_index + 1);
630}
631