1/*-
2 * Copyright (c) 1998 Robert Nordier
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms are freely
6 * permitted provided that the above copyright notice and this
7 * paragraph and the following disclaimer are duplicated in all
8 * such forms.
9 *
10 * This software is provided "AS IS" and without any express or
11 * implied warranties, including, without limitation, the implied
12 * warranties of merchantability and fitness for a particular
13 * purpose.
14 */
15
16#include <sys/cdefs.h>
17__FBSDID("$FreeBSD: stable/11/stand/i386/boot2/boot2.c 332130 2018-04-06 18:55:02Z kevans $");
18
19#include <sys/param.h>
20#include <sys/disklabel.h>
21#include <sys/diskmbr.h>
22#include <sys/dirent.h>
23#include <sys/reboot.h>
24
25#include <machine/bootinfo.h>
26#include <machine/elf.h>
27
28#include <stdarg.h>
29
30#include <a.out.h>
31
32#include <btxv86.h>
33
34#include "boot2.h"
35#include "lib.h"
36#include "paths.h"
37#include "rbx.h"
38
39/* Define to 0 to omit serial support */
40#ifndef SERIAL
41#define SERIAL 1
42#endif
43
44#define IO_KEYBOARD	1
45#define IO_SERIAL	2
46
47#if SERIAL
48#define DO_KBD (ioctrl & IO_KEYBOARD)
49#define DO_SIO (ioctrl & IO_SERIAL)
50#else
51#define DO_KBD (1)
52#define DO_SIO (0)
53#endif
54
55#define SECOND		18	/* Circa that many ticks in a second. */
56
57#define ARGS		0x900
58#define NOPT		14
59#define NDEV		3
60#define MEM_BASE	0x12
61#define MEM_EXT 	0x15
62
63#define DRV_HARD	0x80
64#define DRV_MASK	0x7f
65
66#define TYPE_AD		0
67#define TYPE_DA		1
68#define TYPE_MAXHARD	TYPE_DA
69#define TYPE_FD		2
70
71extern uint32_t _end;
72
73static const char optstr[NOPT] = "DhaCcdgmnpqrsv"; /* Also 'P', 'S' */
74static const unsigned char flags[NOPT] = {
75	RBX_DUAL,
76	RBX_SERIAL,
77	RBX_ASKNAME,
78	RBX_CDROM,
79	RBX_CONFIG,
80	RBX_KDB,
81	RBX_GDB,
82	RBX_MUTE,
83	RBX_NOINTR,
84	RBX_PAUSE,
85	RBX_QUIET,
86	RBX_DFLTROOT,
87	RBX_SINGLE,
88	RBX_VERBOSE
89};
90
91static const char *const dev_nm[NDEV] = {"ad", "da", "fd"};
92static const unsigned char dev_maj[NDEV] = {30, 4, 2};
93
94static struct dsk {
95	unsigned drive;
96	unsigned type;
97	unsigned unit;
98	uint8_t slice;
99	uint8_t part;
100	unsigned start;
101	int init;
102} dsk;
103static char cmd[512], cmddup[512], knamebuf[1024];
104static const char *kname;
105uint32_t opts;
106static struct bootinfo bootinfo;
107#if SERIAL
108static int comspeed = SIOSPD;
109static uint8_t ioctrl = IO_KEYBOARD;
110#endif
111
112int main(void);
113void exit(int);
114static void load(void);
115static int parse(void);
116static int dskread(void *, unsigned, unsigned);
117static void printf(const char *,...);
118static void putchar(int);
119static int drvread(void *, unsigned, unsigned);
120static int keyhit(unsigned);
121static int xputc(int);
122static int xgetc(int);
123static inline int getc(int);
124
125static void memcpy(void *, const void *, int);
126static void
127memcpy(void *dst, const void *src, int len)
128{
129	const char *s;
130	char *d;
131
132	s = src;
133	d = dst;
134
135	while (len--)
136		*d++ = *s++;
137}
138
139static inline int
140strcmp(const char *s1, const char *s2)
141{
142
143	for (; *s1 == *s2 && *s1; s1++, s2++);
144	return ((unsigned char)*s1 - (unsigned char)*s2);
145}
146
147#define	UFS_SMALL_CGBASE
148#include "ufsread.c"
149
150static int
151xfsread(ufs_ino_t inode, void *buf, size_t nbyte)
152{
153
154	if ((size_t)fsread(inode, buf, nbyte) != nbyte) {
155		printf("Invalid %s\n", "format");
156		return (-1);
157	}
158	return (0);
159}
160
161static inline void
162getstr(void)
163{
164	char *s;
165	int c;
166
167	s = cmd;
168	for (;;) {
169		switch (c = xgetc(0)) {
170		case 0:
171			break;
172		case '\177':
173		case '\b':
174			if (s > cmd) {
175				s--;
176				printf("\b \b");
177			}
178			break;
179		case '\n':
180		case '\r':
181			*s = 0;
182			return;
183		default:
184			if (s - cmd < sizeof(cmd) - 1)
185				*s++ = c;
186			putchar(c);
187		}
188	}
189}
190
191static inline void
192putc(int c)
193{
194
195	v86.addr = 0x10;
196	v86.eax = 0xe00 | (c & 0xff);
197	v86.ebx = 0x7;
198	v86int();
199}
200
201int
202main(void)
203{
204	uint8_t autoboot;
205	ufs_ino_t ino;
206	size_t nbyte;
207
208	dmadat = (void *)(roundup2(__base + (int32_t)&_end, 0x10000) - __base);
209	v86.ctl = V86_FLAGS;
210	v86.efl = PSL_RESERVED_DEFAULT | PSL_I;
211	dsk.drive = *(uint8_t *)PTOV(ARGS);
212	dsk.type = dsk.drive & DRV_HARD ? TYPE_AD : TYPE_FD;
213	dsk.unit = dsk.drive & DRV_MASK;
214	dsk.slice = *(uint8_t *)PTOV(ARGS + 1) + 1;
215	bootinfo.bi_version = BOOTINFO_VERSION;
216	bootinfo.bi_size = sizeof(bootinfo);
217
218	/* Process configuration file */
219
220	autoboot = 1;
221
222	if ((ino = lookup(PATH_CONFIG)) ||
223	    (ino = lookup(PATH_DOTCONFIG))) {
224		nbyte = fsread(ino, cmd, sizeof(cmd) - 1);
225		cmd[nbyte] = '\0';
226	}
227
228	if (*cmd) {
229		memcpy(cmddup, cmd, sizeof(cmd));
230		if (parse())
231			autoboot = 0;
232		if (!OPT_CHECK(RBX_QUIET))
233			printf("%s: %s", PATH_CONFIG, cmddup);
234		/* Do not process this command twice */
235		*cmd = 0;
236	}
237
238	/*
239	 * Try to exec stage 3 boot loader. If interrupted by a keypress,
240	 * or in case of failure, try to load a kernel directly instead.
241	 */
242
243	if (!kname) {
244		kname = PATH_LOADER;
245		if (autoboot && !keyhit(3*SECOND)) {
246			load();
247			kname = PATH_KERNEL;
248		}
249	}
250
251	/* Present the user with the boot2 prompt. */
252
253	for (;;) {
254		if (!autoboot || !OPT_CHECK(RBX_QUIET))
255			printf("\nFreeBSD/x86 boot\n"
256				 "Default: %u:%s(%u,%c)%s\n"
257				 "boot: ",
258			    dsk.drive & DRV_MASK, dev_nm[dsk.type], dsk.unit,
259			    'a' + dsk.part, kname);
260		if (DO_SIO)
261			sio_flush();
262		if (!autoboot || keyhit(3*SECOND))
263			getstr();
264		else if (!autoboot || !OPT_CHECK(RBX_QUIET))
265			putchar('\n');
266		autoboot = 0;
267		if (parse())
268			putchar('\a');
269		else
270			load();
271	}
272}
273
274/* XXX - Needed for btxld to link the boot2 binary; do not remove. */
275void
276exit(int x)
277{
278
279}
280
281static void
282load(void)
283{
284	union {
285		struct exec ex;
286		Elf32_Ehdr eh;
287	} hdr;
288	static Elf32_Phdr ep[2];
289	static Elf32_Shdr es[2];
290	caddr_t p;
291	ufs_ino_t ino;
292	uint32_t addr;
293	int k;
294	uint8_t i, j;
295
296	if (!(ino = lookup(kname))) {
297		if (!ls)
298			printf("No %s\n", kname);
299		return;
300	}
301	if (xfsread(ino, &hdr, sizeof(hdr)))
302		return;
303
304	if (N_GETMAGIC(hdr.ex) == ZMAGIC) {
305		addr = hdr.ex.a_entry & 0xffffff;
306		p = PTOV(addr);
307		fs_off = PAGE_SIZE;
308		if (xfsread(ino, p, hdr.ex.a_text))
309			return;
310		p += roundup2(hdr.ex.a_text, PAGE_SIZE);
311		if (xfsread(ino, p, hdr.ex.a_data))
312			return;
313	} else if (IS_ELF(hdr.eh)) {
314		fs_off = hdr.eh.e_phoff;
315		for (j = k = 0; k < hdr.eh.e_phnum && j < 2; k++) {
316			if (xfsread(ino, ep + j, sizeof(ep[0])))
317				return;
318			if (ep[j].p_type == PT_LOAD)
319				j++;
320		}
321		for (i = 0; i < 2; i++) {
322			p = PTOV(ep[i].p_paddr & 0xffffff);
323			fs_off = ep[i].p_offset;
324			if (xfsread(ino, p, ep[i].p_filesz))
325				return;
326		}
327		p += roundup2(ep[1].p_memsz, PAGE_SIZE);
328		bootinfo.bi_symtab = VTOP(p);
329		if (hdr.eh.e_shnum == hdr.eh.e_shstrndx + 3) {
330			fs_off = hdr.eh.e_shoff + sizeof(es[0]) *
331			    (hdr.eh.e_shstrndx + 1);
332			if (xfsread(ino, &es, sizeof(es)))
333				return;
334			for (i = 0; i < 2; i++) {
335				*(Elf32_Word *)p = es[i].sh_size;
336				p += sizeof(es[i].sh_size);
337				fs_off = es[i].sh_offset;
338				if (xfsread(ino, p, es[i].sh_size))
339					return;
340				p += es[i].sh_size;
341			}
342		}
343		addr = hdr.eh.e_entry & 0xffffff;
344		bootinfo.bi_esymtab = VTOP(p);
345	} else {
346		printf("Invalid %s\n", "format");
347		return;
348	}
349
350	bootinfo.bi_kernelname = VTOP(kname);
351	bootinfo.bi_bios_dev = dsk.drive;
352	__exec((caddr_t)addr, RB_BOOTINFO | (opts & RBX_MASK),
353	    MAKEBOOTDEV(dev_maj[dsk.type], dsk.slice, dsk.unit, dsk.part),
354	    0, 0, 0, VTOP(&bootinfo));
355}
356
357static int
358parse()
359{
360	char *arg, *ep, *p, *q;
361	const char *cp;
362	unsigned int drv;
363	int c, i, j;
364	size_t k;
365
366	arg = cmd;
367
368	while ((c = *arg++)) {
369		if (c == ' ' || c == '\t' || c == '\n')
370			continue;
371		for (p = arg; *p && *p != '\n' && *p != ' ' && *p != '\t'; p++);
372		ep = p;
373		if (*p)
374			*p++ = 0;
375		if (c == '-') {
376			while ((c = *arg++)) {
377				if (c == 'P') {
378					if (*(uint8_t *)PTOV(0x496) & 0x10) {
379						cp = "yes";
380					} else {
381						opts |= OPT_SET(RBX_DUAL) |
382						    OPT_SET(RBX_SERIAL);
383						cp = "no";
384					}
385					printf("Keyboard: %s\n", cp);
386					continue;
387#if SERIAL
388				} else if (c == 'S') {
389					j = 0;
390					while ((u_int)(i = *arg++ - '0') <= 9)
391						j = j * 10 + i;
392					if (j > 0 && i == -'0') {
393						comspeed = j;
394						break;
395					}
396					/*
397					 * Fall through to error below
398					 * ('S' not in optstr[]).
399					 */
400#endif
401				}
402				for (i = 0; c != optstr[i]; i++)
403					if (i == NOPT - 1)
404						return (-1);
405				opts ^= OPT_SET(flags[i]);
406			}
407#if SERIAL
408			ioctrl = OPT_CHECK(RBX_DUAL) ? (IO_SERIAL|IO_KEYBOARD) :
409			    OPT_CHECK(RBX_SERIAL) ? IO_SERIAL : IO_KEYBOARD;
410			if (DO_SIO) {
411				if (sio_init(115200 / comspeed) != 0)
412					ioctrl &= ~IO_SERIAL;
413			}
414#endif
415		} else {
416			for (q = arg--; *q && *q != '('; q++);
417			if (*q) {
418				drv = -1;
419				if (arg[1] == ':') {
420					drv = *arg - '0';
421					if (drv > 9)
422						return (-1);
423					arg += 2;
424				}
425				if (q - arg != 2)
426					return (-1);
427				for (i = 0; arg[0] != dev_nm[i][0] ||
428				    arg[1] != dev_nm[i][1]; i++)
429					if (i == NDEV - 1)
430						return (-1);
431				dsk.type = i;
432				arg += 3;
433				dsk.unit = *arg - '0';
434				if (arg[1] != ',' || dsk.unit > 9)
435					return (-1);
436				arg += 2;
437				dsk.slice = WHOLE_DISK_SLICE;
438				if (arg[1] == ',') {
439					dsk.slice = *arg - '0' + 1;
440					if (dsk.slice > NDOSPART + 1)
441						return (-1);
442					arg += 2;
443				}
444				if (arg[1] != ')')
445					return (-1);
446				dsk.part = *arg - 'a';
447				if (dsk.part > 7)
448					return (-1);
449				arg += 2;
450				if (drv == -1)
451					drv = dsk.unit;
452				dsk.drive = (dsk.type <= TYPE_MAXHARD
453				    ? DRV_HARD : 0) + drv;
454				dsk_meta = 0;
455			}
456			k = ep - arg;
457			if (k > 0) {
458				if (k >= sizeof(knamebuf))
459					return (-1);
460				memcpy(knamebuf, arg, k + 1);
461				kname = knamebuf;
462			}
463		}
464		arg = p;
465	}
466	return (0);
467}
468
469static int
470dskread(void *buf, unsigned lba, unsigned nblk)
471{
472	struct dos_partition *dp;
473	struct disklabel *d;
474	char *sec;
475	unsigned i;
476	uint8_t sl;
477	const char *reason;
478
479	if (!dsk_meta) {
480		sec = dmadat->secbuf;
481		dsk.start = 0;
482		if (drvread(sec, DOSBBSECTOR, 1))
483			return (-1);
484		dp = (void *)(sec + DOSPARTOFF);
485		sl = dsk.slice;
486		if (sl < BASE_SLICE) {
487			for (i = 0; i < NDOSPART; i++)
488				if (dp[i].dp_typ == DOSPTYP_386BSD &&
489				    (dp[i].dp_flag & 0x80 || sl < BASE_SLICE)) {
490					sl = BASE_SLICE + i;
491					if (dp[i].dp_flag & 0x80 ||
492					    dsk.slice == COMPATIBILITY_SLICE)
493						break;
494				}
495			if (dsk.slice == WHOLE_DISK_SLICE)
496				dsk.slice = sl;
497		}
498		if (sl != WHOLE_DISK_SLICE) {
499			if (sl != COMPATIBILITY_SLICE)
500				dp += sl - BASE_SLICE;
501			if (dp->dp_typ != DOSPTYP_386BSD) {
502				reason = "slice";
503				goto error;
504			}
505			dsk.start = dp->dp_start;
506		}
507		if (drvread(sec, dsk.start + LABELSECTOR, 1))
508			return (-1);
509		d = (void *)(sec + LABELOFFSET);
510		if (d->d_magic != DISKMAGIC || d->d_magic2 != DISKMAGIC) {
511			if (dsk.part != RAW_PART) {
512				reason = "label";
513				goto error;
514			}
515		} else {
516			if (!dsk.init) {
517				if (d->d_type == DTYPE_SCSI)
518					dsk.type = TYPE_DA;
519				dsk.init++;
520			}
521			if (dsk.part >= d->d_npartitions ||
522			    !d->d_partitions[dsk.part].p_size) {
523				reason = "partition";
524				goto error;
525			}
526			dsk.start += d->d_partitions[dsk.part].p_offset;
527			dsk.start -= d->d_partitions[RAW_PART].p_offset;
528		}
529	}
530	return (drvread(buf, dsk.start + lba, nblk));
531error:
532	printf("Invalid %s\n", reason);
533	return (-1);
534}
535
536static void
537printf(const char *fmt,...)
538{
539	va_list ap;
540	static char buf[10];
541	char *s;
542	unsigned u;
543	int c;
544
545	va_start(ap, fmt);
546	while ((c = *fmt++)) {
547		if (c == '%') {
548			c = *fmt++;
549			switch (c) {
550			case 'c':
551				putchar(va_arg(ap, int));
552				continue;
553			case 's':
554				for (s = va_arg(ap, char *); *s; s++)
555					putchar(*s);
556				continue;
557			case 'u':
558				u = va_arg(ap, unsigned);
559				s = buf;
560				do
561					*s++ = '0' + u % 10U;
562				while (u /= 10U);
563				while (--s >= buf)
564					putchar(*s);
565				continue;
566			}
567		}
568		putchar(c);
569	}
570	va_end(ap);
571	return;
572}
573
574static void
575putchar(int c)
576{
577
578	if (c == '\n')
579		xputc('\r');
580	xputc(c);
581}
582
583static int
584drvread(void *buf, unsigned lba, unsigned nblk)
585{
586	static unsigned c = 0x2d5c7c2f;
587
588	if (!OPT_CHECK(RBX_QUIET)) {
589		xputc(c = c << 8 | c >> 24);
590		xputc('\b');
591	}
592	v86.ctl = V86_ADDR | V86_CALLF | V86_FLAGS;
593	v86.addr = XREADORG;		/* call to xread in boot1 */
594	v86.es = VTOPSEG(buf);
595	v86.eax = lba;
596	v86.ebx = VTOPOFF(buf);
597	v86.ecx = lba >> 16;
598	v86.edx = nblk << 8 | dsk.drive;
599	v86int();
600	v86.ctl = V86_FLAGS;
601	if (V86_CY(v86.efl)) {
602		printf("error %u lba %u\n", v86.eax >> 8 & 0xff, lba);
603		return (-1);
604	}
605	return (0);
606}
607
608static int
609keyhit(unsigned ticks)
610{
611	uint32_t t0, t1;
612
613	if (OPT_CHECK(RBX_NOINTR))
614		return (0);
615	t0 = 0;
616	for (;;) {
617		if (xgetc(1))
618			return (1);
619		t1 = *(uint32_t *)PTOV(0x46c);
620		if (!t0)
621			t0 = t1;
622		if ((uint32_t)(t1 - t0) >= ticks)
623			return (0);
624	}
625}
626
627static int
628xputc(int c)
629{
630
631	if (DO_KBD)
632		putc(c);
633	if (DO_SIO)
634		sio_putc(c);
635	return (c);
636}
637
638static int
639getc(int fn)
640{
641
642	v86.addr = 0x16;
643	v86.eax = fn << 8;
644	v86int();
645	return (fn == 0 ? v86.eax & 0xff : !V86_ZR(v86.efl));
646}
647
648static int
649xgetc(int fn)
650{
651
652	if (OPT_CHECK(RBX_NOINTR))
653		return (0);
654	for (;;) {
655		if (DO_KBD && getc(1))
656			return (fn ? 1 : getc(0));
657		if (DO_SIO && sio_ischar())
658			return (fn ? 1 : sio_getc());
659		if (fn)
660			return (0);
661	}
662}
663