xref: /freebsd/stand/i386/boot2/boot2.c (revision d37eb51047221dc3322b34db1038ff3aa533883f)
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/param.h>
17 #include <sys/disklabel.h>
18 #include <sys/diskmbr.h>
19 #include <sys/dirent.h>
20 #include <sys/reboot.h>
21 
22 #include <machine/bootinfo.h>
23 #include <machine/elf.h>
24 
25 #include <stdarg.h>
26 
27 #include <a.out.h>
28 
29 #include <btxv86.h>
30 
31 #include "boot2.h"
32 #include "lib.h"
33 #include "paths.h"
34 #include "rbx.h"
35 
36 /* Define to 0 to omit serial support */
37 #ifndef SERIAL
38 #define SERIAL 1
39 #endif
40 
41 #define IO_KEYBOARD	1
42 #define IO_SERIAL	2
43 
44 #if SERIAL
45 #define DO_KBD (ioctrl & IO_KEYBOARD)
46 #define DO_SIO (ioctrl & IO_SERIAL)
47 #else
48 #define DO_KBD (1)
49 #define DO_SIO (0)
50 #endif
51 
52 #define SECOND		18	/* Circa that many ticks in a second. */
53 
54 #define ARGS		0x900
55 #define NOPT		14
56 #define NDEV		3
57 #define MEM_BASE	0x12
58 #define MEM_EXT 	0x15
59 
60 #define DRV_HARD	0x80
61 #define DRV_MASK	0x7f
62 
63 #define TYPE_AD		0
64 #define TYPE_DA		1
65 #define TYPE_MAXHARD	TYPE_DA
66 #define TYPE_FD		2
67 
68 extern uint32_t _end;
69 
70 static const char optstr[NOPT] = "DhaCcdgmnpqrsv"; /* Also 'P', 'S' */
71 static const unsigned char flags[NOPT] = {
72 	RBX_DUAL,
73 	RBX_SERIAL,
74 	RBX_ASKNAME,
75 	RBX_CDROM,
76 	RBX_CONFIG,
77 	RBX_KDB,
78 	RBX_GDB,
79 	RBX_MUTE,
80 	RBX_NOINTR,
81 	RBX_PAUSE,
82 	RBX_QUIET,
83 	RBX_DFLTROOT,
84 	RBX_SINGLE,
85 	RBX_VERBOSE
86 };
87 
88 static const char *const dev_nm[NDEV] = {"ad", "da", "fd"};
89 static const unsigned char dev_maj[NDEV] = {30, 4, 2};
90 
91 static struct dsk {
92 	unsigned drive;
93 	unsigned type;
94 	unsigned unit;
95 	uint8_t slice;
96 	uint8_t part;
97 	unsigned start;
98 	int init;
99 } dsk;
100 static char cmd[512], cmddup[512], knamebuf[1024];
101 static const char *kname;
102 uint32_t opts;
103 static struct bootinfo bootinfo;
104 #if SERIAL
105 static int comspeed = SIOSPD;
106 static uint8_t ioctrl = IO_KEYBOARD;
107 #endif
108 
109 int main(void);
110 void exit(int);
111 static void load(void);
112 static int parse(void);
113 static int dskread(void *, unsigned, unsigned);
114 static void printf(const char *,...);
115 static void putchar(int);
116 static int drvread(void *, unsigned, unsigned);
117 static int keyhit(unsigned);
118 static int xputc(int);
119 static int xgetc(int);
120 static inline int getc(int);
121 
122 static void memcpy(void *, const void *, int);
123 static void
124 memcpy(void *dst, const void *src, int len)
125 {
126 	const char *s;
127 	char *d;
128 
129 	s = src;
130 	d = dst;
131 
132 	while (len--)
133 		*d++ = *s++;
134 }
135 
136 static inline int
137 strcmp(const char *s1, const char *s2)
138 {
139 
140 	for (; *s1 == *s2 && *s1; s1++, s2++);
141 	return ((unsigned char)*s1 - (unsigned char)*s2);
142 }
143 
144 #define	UFS_SMALL_CGBASE
145 #include "ufsread.c"
146 
147 static int
148 xfsread(ufs_ino_t inode, void *buf, size_t nbyte)
149 {
150 
151 	if ((size_t)fsread(inode, buf, nbyte) != nbyte) {
152 		printf("Invalid %s\n", "format");
153 		return (-1);
154 	}
155 	return (0);
156 }
157 
158 static inline void
159 getstr(void)
160 {
161 	char *s;
162 	int c;
163 
164 	s = cmd;
165 	for (;;) {
166 		switch (c = xgetc(0)) {
167 		case 0:
168 			break;
169 		case '\177':
170 		case '\b':
171 			if (s > cmd) {
172 				s--;
173 				printf("\b \b");
174 			}
175 			break;
176 		case '\n':
177 		case '\r':
178 			*s = 0;
179 			return;
180 		default:
181 			if (s - cmd < sizeof(cmd) - 1)
182 				*s++ = c;
183 			putchar(c);
184 		}
185 	}
186 }
187 
188 static inline void
189 putc(int c)
190 {
191 
192 	v86.addr = 0x10;
193 	v86.eax = 0xe00 | (c & 0xff);
194 	v86.ebx = 0x7;
195 	v86int();
196 }
197 
198 int
199 main(void)
200 {
201 	uint8_t autoboot;
202 	ufs_ino_t ino;
203 	size_t nbyte;
204 
205 	dmadat = (void *)(roundup2(__base + (int32_t)&_end, 0x10000) - __base);
206 	v86.ctl = V86_FLAGS;
207 	v86.efl = PSL_RESERVED_DEFAULT | PSL_I;
208 	dsk.drive = *(uint8_t *)PTOV(ARGS);
209 	dsk.type = dsk.drive & DRV_HARD ? TYPE_AD : TYPE_FD;
210 	dsk.unit = dsk.drive & DRV_MASK;
211 	dsk.slice = *(uint8_t *)PTOV(ARGS + 1) + 1;
212 	bootinfo.bi_version = BOOTINFO_VERSION;
213 	bootinfo.bi_size = sizeof(bootinfo);
214 
215 	/* Process configuration file */
216 
217 	autoboot = 1;
218 
219 	if ((ino = lookup(PATH_CONFIG)) ||
220 	    (ino = lookup(PATH_DOTCONFIG))) {
221 		nbyte = fsread(ino, cmd, sizeof(cmd) - 1);
222 		cmd[nbyte] = '\0';
223 	}
224 
225 	if (*cmd) {
226 		memcpy(cmddup, cmd, sizeof(cmd));
227 		if (parse())
228 			autoboot = 0;
229 		if (!OPT_CHECK(RBX_QUIET))
230 			printf("%s: %s", PATH_CONFIG, cmddup);
231 		/* Do not process this command twice */
232 		*cmd = 0;
233 	}
234 
235 	/*
236 	 * Try to exec stage 3 boot loader. If interrupted by a keypress,
237 	 * or in case of failure, try to load a kernel directly instead.
238 	 */
239 
240 	if (!kname) {
241 		kname = PATH_LOADER;
242 		if (autoboot && !keyhit(3*SECOND)) {
243 			load();
244 			kname = PATH_KERNEL;
245 		}
246 	}
247 
248 	/* Present the user with the boot2 prompt. */
249 
250 	for (;;) {
251 		if (!autoboot || !OPT_CHECK(RBX_QUIET))
252 			printf("\nFreeBSD/x86 boot\n"
253 				 "Default: %u:%s(%u,%c)%s\n"
254 				 "boot: ",
255 			    dsk.drive & DRV_MASK, dev_nm[dsk.type], dsk.unit,
256 			    'a' + dsk.part, kname);
257 		if (DO_SIO)
258 			sio_flush();
259 		if (!autoboot || keyhit(3*SECOND))
260 			getstr();
261 		else if (!autoboot || !OPT_CHECK(RBX_QUIET))
262 			putchar('\n');
263 		autoboot = 0;
264 		if (parse())
265 			putchar('\a');
266 		else
267 			load();
268 	}
269 }
270 
271 /* XXX - Needed for btxld to link the boot2 binary; do not remove. */
272 void
273 exit(int x)
274 {
275 
276 }
277 
278 static void
279 load(void)
280 {
281 	union {
282 		struct exec ex;
283 		Elf32_Ehdr eh;
284 	} hdr;
285 	static Elf32_Phdr ep[2];
286 	static Elf32_Shdr es[2];
287 	caddr_t p;
288 	ufs_ino_t ino;
289 	uint32_t addr;
290 	int k;
291 	uint8_t i, j;
292 
293 	if (!(ino = lookup(kname))) {
294 		if (!ls)
295 			printf("No %s\n", kname);
296 		return;
297 	}
298 	if (xfsread(ino, &hdr, sizeof(hdr)))
299 		return;
300 
301 	if (N_GETMAGIC(hdr.ex) == ZMAGIC) {
302 		addr = hdr.ex.a_entry & 0xffffff;
303 		p = PTOV(addr);
304 		fs_off = PAGE_SIZE;
305 		if (xfsread(ino, p, hdr.ex.a_text))
306 			return;
307 		p += roundup2(hdr.ex.a_text, PAGE_SIZE);
308 		if (xfsread(ino, p, hdr.ex.a_data))
309 			return;
310 	} else if (IS_ELF(hdr.eh)) {
311 		fs_off = hdr.eh.e_phoff;
312 		for (j = k = 0; k < hdr.eh.e_phnum && j < 2; k++) {
313 			if (xfsread(ino, ep + j, sizeof(ep[0])))
314 				return;
315 			if (ep[j].p_type == PT_LOAD)
316 				j++;
317 		}
318 		for (i = 0; i < 2; i++) {
319 			p = PTOV(ep[i].p_paddr & 0xffffff);
320 			fs_off = ep[i].p_offset;
321 			if (xfsread(ino, p, ep[i].p_filesz))
322 				return;
323 		}
324 		p += roundup2(ep[1].p_memsz, PAGE_SIZE);
325 		bootinfo.bi_symtab = VTOP(p);
326 		if (hdr.eh.e_shnum == hdr.eh.e_shstrndx + 3) {
327 			fs_off = hdr.eh.e_shoff + sizeof(es[0]) *
328 			    (hdr.eh.e_shstrndx + 1);
329 			if (xfsread(ino, &es, sizeof(es)))
330 				return;
331 			for (i = 0; i < 2; i++) {
332 				*(Elf32_Word *)p = es[i].sh_size;
333 				p += sizeof(es[i].sh_size);
334 				fs_off = es[i].sh_offset;
335 				if (xfsread(ino, p, es[i].sh_size))
336 					return;
337 				p += es[i].sh_size;
338 			}
339 		}
340 		addr = hdr.eh.e_entry & 0xffffff;
341 		bootinfo.bi_esymtab = VTOP(p);
342 	} else {
343 		printf("Invalid %s\n", "format");
344 		return;
345 	}
346 
347 	bootinfo.bi_kernelname = VTOP(kname);
348 	bootinfo.bi_bios_dev = dsk.drive;
349 	__exec((caddr_t)addr, RB_BOOTINFO | (opts & RBX_MASK),
350 	    MAKEBOOTDEV(dev_maj[dsk.type], dsk.slice, dsk.unit, dsk.part),
351 	    0, 0, 0, VTOP(&bootinfo));
352 }
353 
354 static int
355 parse(void)
356 {
357 	char *arg, *ep, *p, *q;
358 	const char *cp;
359 	unsigned int drv;
360 	int c, i, j;
361 	size_t k;
362 
363 	arg = cmd;
364 
365 	while ((c = *arg++)) {
366 		if (c == ' ' || c == '\t' || c == '\n')
367 			continue;
368 		for (p = arg; *p && *p != '\n' && *p != ' ' && *p != '\t'; p++);
369 		ep = p;
370 		if (*p)
371 			*p++ = 0;
372 		if (c == '-') {
373 			while ((c = *arg++)) {
374 				if (c == 'P') {
375 					if (*(uint8_t *)PTOV(0x496) & 0x10) {
376 						cp = "yes";
377 					} else {
378 						opts |= OPT_SET(RBX_DUAL) |
379 						    OPT_SET(RBX_SERIAL);
380 						cp = "no";
381 					}
382 					printf("Keyboard: %s\n", cp);
383 					continue;
384 #if SERIAL
385 				} else if (c == 'S') {
386 					j = 0;
387 					while ((u_int)(i = *arg++ - '0') <= 9)
388 						j = j * 10 + i;
389 					if (j > 0 && i == -'0') {
390 						comspeed = j;
391 						break;
392 					}
393 					/*
394 					 * Fall through to error below
395 					 * ('S' not in optstr[]).
396 					 */
397 #endif
398 				}
399 				for (i = 0; c != optstr[i]; i++)
400 					if (i == NOPT - 1)
401 						return (-1);
402 				opts ^= OPT_SET(flags[i]);
403 			}
404 #if SERIAL
405 			ioctrl = OPT_CHECK(RBX_DUAL) ? (IO_SERIAL|IO_KEYBOARD) :
406 			    OPT_CHECK(RBX_SERIAL) ? IO_SERIAL : IO_KEYBOARD;
407 			if (DO_SIO) {
408 				if (sio_init(115200 / comspeed) != 0)
409 					ioctrl &= ~IO_SERIAL;
410 			}
411 #endif
412 		} else {
413 			for (q = arg--; *q && *q != '('; q++);
414 			if (*q) {
415 				drv = -1;
416 				if (arg[1] == ':') {
417 					drv = *arg - '0';
418 					if (drv > 9)
419 						return (-1);
420 					arg += 2;
421 				}
422 				if (q - arg != 2)
423 					return (-1);
424 				for (i = 0; arg[0] != dev_nm[i][0] ||
425 				    arg[1] != dev_nm[i][1]; i++)
426 					if (i == NDEV - 1)
427 						return (-1);
428 				dsk.type = i;
429 				arg += 3;
430 				dsk.unit = *arg - '0';
431 				if (arg[1] != ',' || dsk.unit > 9)
432 					return (-1);
433 				arg += 2;
434 				dsk.slice = WHOLE_DISK_SLICE;
435 				if (arg[1] == ',') {
436 					dsk.slice = *arg - '0' + 1;
437 					if (dsk.slice > NDOSPART + 1)
438 						return (-1);
439 					arg += 2;
440 				}
441 				if (arg[1] != ')')
442 					return (-1);
443 				dsk.part = *arg - 'a';
444 				if (dsk.part > 7)
445 					return (-1);
446 				arg += 2;
447 				if (drv == -1)
448 					drv = dsk.unit;
449 				dsk.drive = (dsk.type <= TYPE_MAXHARD
450 				    ? DRV_HARD : 0) + drv;
451 				dsk_meta = 0;
452 			}
453 			k = ep - arg;
454 			if (k > 0) {
455 				if (k >= sizeof(knamebuf))
456 					return (-1);
457 				memcpy(knamebuf, arg, k + 1);
458 				kname = knamebuf;
459 			}
460 		}
461 		arg = p;
462 	}
463 	return (0);
464 }
465 
466 static int
467 dskread(void *buf, unsigned lba, unsigned nblk)
468 {
469 	struct dos_partition *dp;
470 	struct disklabel *d;
471 	char *sec;
472 	unsigned i;
473 	uint8_t sl;
474 	const char *reason;
475 
476 	if (!dsk_meta) {
477 		sec = dmadat->secbuf;
478 		dsk.start = 0;
479 		if (drvread(sec, DOSBBSECTOR, 1))
480 			return (-1);
481 		dp = (void *)(sec + DOSPARTOFF);
482 		sl = dsk.slice;
483 		if (sl < BASE_SLICE) {
484 			for (i = 0; i < NDOSPART; i++)
485 				if (dp[i].dp_typ == DOSPTYP_386BSD &&
486 				    (dp[i].dp_flag & 0x80 || sl < BASE_SLICE)) {
487 					sl = BASE_SLICE + i;
488 					if (dp[i].dp_flag & 0x80 ||
489 					    dsk.slice == COMPATIBILITY_SLICE)
490 						break;
491 				}
492 			if (dsk.slice == WHOLE_DISK_SLICE)
493 				dsk.slice = sl;
494 		}
495 		if (sl != WHOLE_DISK_SLICE) {
496 			if (sl != COMPATIBILITY_SLICE)
497 				dp += sl - BASE_SLICE;
498 			if (dp->dp_typ != DOSPTYP_386BSD) {
499 				reason = "slice";
500 				goto error;
501 			}
502 			dsk.start = dp->dp_start;
503 		}
504 		if (drvread(sec, dsk.start + LABELSECTOR, 1))
505 			return (-1);
506 		d = (void *)(sec + LABELOFFSET);
507 		if (d->d_magic != DISKMAGIC || d->d_magic2 != DISKMAGIC) {
508 			if (dsk.part != RAW_PART) {
509 				reason = "label";
510 				goto error;
511 			}
512 		} else {
513 			if (!dsk.init) {
514 				if (d->d_type == DTYPE_SCSI)
515 					dsk.type = TYPE_DA;
516 				dsk.init++;
517 			}
518 			if (dsk.part >= d->d_npartitions ||
519 			    !d->d_partitions[dsk.part].p_size) {
520 				reason = "partition";
521 				goto error;
522 			}
523 			dsk.start += d->d_partitions[dsk.part].p_offset;
524 			dsk.start -= d->d_partitions[RAW_PART].p_offset;
525 		}
526 	}
527 	return (drvread(buf, dsk.start + lba, nblk));
528 error:
529 	printf("Invalid %s\n", reason);
530 	return (-1);
531 }
532 
533 static void
534 printf(const char *fmt,...)
535 {
536 	va_list ap;
537 	static char buf[10];
538 	char *s;
539 	unsigned u;
540 	int c;
541 
542 	va_start(ap, fmt);
543 	while ((c = *fmt++)) {
544 		if (c == '%') {
545 			c = *fmt++;
546 			switch (c) {
547 			case 'c':
548 				putchar(va_arg(ap, int));
549 				continue;
550 			case 's':
551 				for (s = va_arg(ap, char *); *s; s++)
552 					putchar(*s);
553 				continue;
554 			case 'u':
555 				u = va_arg(ap, unsigned);
556 				s = buf;
557 				do
558 					*s++ = '0' + u % 10U;
559 				while (u /= 10U);
560 				while (--s >= buf)
561 					putchar(*s);
562 				continue;
563 			}
564 		}
565 		putchar(c);
566 	}
567 	va_end(ap);
568 	return;
569 }
570 
571 static void
572 putchar(int c)
573 {
574 
575 	if (c == '\n')
576 		xputc('\r');
577 	xputc(c);
578 }
579 
580 static int
581 drvread(void *buf, unsigned lba, unsigned nblk)
582 {
583 	static unsigned c = 0x2d5c7c2f;
584 
585 	if (!OPT_CHECK(RBX_QUIET)) {
586 		xputc(c = c << 8 | c >> 24);
587 		xputc('\b');
588 	}
589 	v86.ctl = V86_ADDR | V86_CALLF | V86_FLAGS;
590 	v86.addr = XREADORG;		/* call to xread in boot1 */
591 	v86.es = VTOPSEG(buf);
592 	v86.eax = lba;
593 	v86.ebx = VTOPOFF(buf);
594 	v86.ecx = lba >> 16;
595 	v86.edx = nblk << 8 | dsk.drive;
596 	v86int();
597 	v86.ctl = V86_FLAGS;
598 	if (V86_CY(v86.efl)) {
599 		printf("error %u lba %u\n", v86.eax >> 8 & 0xff, lba);
600 		return (-1);
601 	}
602 	return (0);
603 }
604 
605 static int
606 keyhit(unsigned ticks)
607 {
608 	uint32_t t0, t1;
609 
610 	if (OPT_CHECK(RBX_NOINTR))
611 		return (0);
612 	t0 = 0;
613 	for (;;) {
614 		if (xgetc(1))
615 			return (1);
616 		t1 = *(uint32_t *)PTOV(0x46c);
617 		if (!t0)
618 			t0 = t1;
619 		if ((uint32_t)(t1 - t0) >= ticks)
620 			return (0);
621 	}
622 }
623 
624 static int
625 xputc(int c)
626 {
627 
628 	if (DO_KBD)
629 		putc(c);
630 	if (DO_SIO)
631 		sio_putc(c);
632 	return (c);
633 }
634 
635 static int
636 getc(int fn)
637 {
638 
639 	v86.addr = 0x16;
640 	v86.eax = fn << 8;
641 	v86int();
642 	return (fn == 0 ? v86.eax & 0xff : !V86_ZR(v86.efl));
643 }
644 
645 static int
646 xgetc(int fn)
647 {
648 
649 	if (OPT_CHECK(RBX_NOINTR))
650 		return (0);
651 	for (;;) {
652 		if (DO_KBD && getc(1))
653 			return (fn ? 1 : getc(0));
654 		if (DO_SIO && sio_ischar())
655 			return (fn ? 1 : sio_getc());
656 		if (fn)
657 			return (0);
658 	}
659 }
660