boot2.c revision 122433 
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: head/sys/boot/i386/boot2/boot2.c 122433 2003-11-10 19:06:09Z bde $");
18
19#include <sys/param.h>
20#include <sys/disklabel.h>
21#include <sys/diskmbr.h>
22#include <sys/dirent.h>
23#include <machine/bootinfo.h>
24#include <machine/elf.h>
25
26#include <stdarg.h>
27
28#include <a.out.h>
29
30#include <btxv86.h>
31
32#include "boot2.h"
33#include "lib.h"
34
35#define IO_KEYBOARD	1
36#define IO_SERIAL	2
37
38#define SECOND		18	/* Circa that many ticks in a second. */
39
40#define RBX_ASKNAME	0x0	/* -a */
41#define RBX_SINGLE	0x1	/* -s */
42#define RBX_DFLTROOT	0x5	/* -r */
43#define RBX_KDB 	0x6	/* -d */
44#define RBX_CONFIG	0xa	/* -c */
45#define RBX_VERBOSE	0xb	/* -v */
46#define RBX_SERIAL	0xc	/* -h */
47#define RBX_CDROM	0xd	/* -C */
48#define RBX_GDB 	0xf	/* -g */
49#define RBX_MUTE	0x10	/* -m */
50#define RBX_PAUSE	0x12	/* -p */
51#define RBX_NOINTR	0x1c	/* -n */
52#define RBX_DUAL	0x1d	/* -D */
53#define RBX_PROBEKBD	0x1e	/* -P */
54/* 0x1f is reserved for the RB_BOOTINFO flag. */
55
56/* pass: -a, -s, -r, -d, -c, -v, -h, -C, -g, -m, -p, -D */
57#define RBX_MASK	0x2005ffff
58
59#define PATH_CONFIG	"/boot.config"
60#define PATH_BOOT3	"/boot/loader"
61#define PATH_KERNEL	"/kernel"
62
63#define ARGS		0x900
64#define NOPT		12
65#define NDEV		3
66#define MEM_BASE	0x12
67#define MEM_EXT 	0x15
68#define V86_CY(x)	((x) & 1)
69#define V86_ZR(x)	((x) & 0x40)
70
71#define DRV_HARD	0x80
72#define DRV_MASK	0x7f
73
74#define TYPE_AD		0
75#define TYPE_DA		1
76#define TYPE_MAXHARD	TYPE_DA
77#define TYPE_FD		2
78
79extern uint32_t _end;
80
81static const char optstr[NOPT] = "DhaCgmnPprsv";
82static const unsigned char flags[NOPT] = {
83    RBX_DUAL,
84    RBX_SERIAL,
85    RBX_ASKNAME,
86    RBX_CDROM,
87    RBX_GDB,
88    RBX_MUTE,
89    RBX_NOINTR,
90    RBX_PROBEKBD,
91    RBX_PAUSE,
92    RBX_DFLTROOT,
93    RBX_SINGLE,
94    RBX_VERBOSE
95};
96
97static const char *const dev_nm[NDEV] = {"ad", "da", "fd"};
98static const unsigned char dev_maj[NDEV] = {30, 4, 2};
99
100static struct dsk {
101    unsigned drive;
102    unsigned type;
103    unsigned unit;
104    unsigned slice;
105    unsigned part;
106    unsigned start;
107    int init;
108} dsk;
109static char cmd[512];
110static char kname[1024];
111static uint32_t opts;
112static struct bootinfo bootinfo;
113static uint8_t ioctrl = IO_KEYBOARD;
114
115void exit(int);
116static void load(void);
117static int parse(void);
118static int xfsread(ino_t, void *, size_t);
119static int dskread(void *, unsigned, unsigned);
120static void printf(const char *,...);
121static void putchar(int);
122static uint32_t memsize(void);
123static int drvread(void *, unsigned, unsigned);
124static int keyhit(unsigned);
125static int xputc(int);
126static int xgetc(int);
127static int getc(int);
128
129#define memcpy __builtin_memcpy
130
131static inline int
132strcmp(const char *s1, const char *s2)
133{
134    for (; *s1 == *s2 && *s1; s1++, s2++);
135    return (unsigned char)*s1 - (unsigned char)*s2;
136}
137
138#include "ufsread.c"
139
140static int
141xfsread(ino_t inode, void *buf, size_t nbyte)
142{
143    if ((size_t)fsread(inode, buf, nbyte) != nbyte) {
144	printf("Invalid %s\n", "format");
145	return -1;
146    }
147    return 0;
148}
149
150static inline uint32_t
151memsize(void)
152{
153    v86.addr = MEM_EXT;
154    v86.eax = 0x8800;
155    v86int();
156    return v86.eax;
157}
158
159static inline void
160getstr(void)
161{
162    char *s;
163    int c;
164
165    s = cmd;
166    for (;;) {
167	switch (c = xgetc(0)) {
168	case 0:
169	    break;
170	case '\177':
171	case '\b':
172	    if (s > cmd) {
173		s--;
174		printf("\b \b");
175	    }
176	    break;
177	case '\n':
178	case '\r':
179	    *s = 0;
180	    return;
181	default:
182	    if (s - cmd < sizeof(cmd) - 1)
183		*s++ = c;
184	    putchar(c);
185	}
186    }
187}
188
189static inline void
190putc(int c)
191{
192    v86.addr = 0x10;
193    v86.eax = 0xe00 | (c & 0xff);
194    v86.ebx = 0x7;
195    v86int();
196}
197
198int
199main(void)
200{
201    int autoboot;
202    ino_t ino;
203
204    dmadat = (void *)(roundup2(__base + (int32_t)&_end, 0x10000) - __base);
205    v86.ctl = V86_FLAGS;
206    dsk.drive = *(uint8_t *)PTOV(ARGS);
207    dsk.type = dsk.drive & DRV_HARD ? TYPE_AD : TYPE_FD;
208    dsk.unit = dsk.drive & DRV_MASK;
209    dsk.slice = *(uint8_t *)PTOV(ARGS + 1) + 1;
210    bootinfo.bi_version = BOOTINFO_VERSION;
211    bootinfo.bi_size = sizeof(bootinfo);
212    bootinfo.bi_basemem = 0;	/* XXX will be filled by loader or kernel */
213    bootinfo.bi_extmem = memsize();
214    bootinfo.bi_memsizes_valid++;
215
216    /* Process configuration file */
217
218    autoboot = 1;
219
220    if ((ino = lookup(PATH_CONFIG)))
221	fsread(ino, cmd, sizeof(cmd));
222
223    if (*cmd) {
224	printf("%s: %s", PATH_CONFIG, cmd);
225	if (parse())
226	    autoboot = 0;
227	/* Do not process this command twice */
228	*cmd = 0;
229    }
230
231    /*
232     * Try to exec stage 3 boot loader. If interrupted by a keypress,
233     * or in case of failure, try to load a kernel directly instead.
234     */
235
236    if (autoboot && !*kname) {
237	memcpy(kname, PATH_BOOT3, sizeof(PATH_BOOT3));
238	if (!keyhit(3*SECOND)) {
239	    load();
240	    memcpy(kname, PATH_KERNEL, sizeof(PATH_KERNEL));
241	}
242    }
243
244    /* Present the user with the boot2 prompt. */
245
246    for (;;) {
247	printf("\nFreeBSD/i386 boot\n"
248	       "Default: %u:%s(%u,%c)%s\n"
249	       "boot: ",
250	       dsk.drive & DRV_MASK, dev_nm[dsk.type], dsk.unit,
251	       'a' + dsk.part, kname);
252	if (ioctrl & IO_SERIAL)
253	    sio_flush();
254	if (!autoboot || keyhit(5*SECOND))
255	    getstr();
256	else
257	    putchar('\n');
258	autoboot = 0;
259	if (parse())
260	    putchar('\a');
261	else
262	    load();
263    }
264}
265
266/* XXX - Needed for btxld to link the boot2 binary; do not remove. */
267void
268exit(int x)
269{
270}
271
272static void
273load(void)
274{
275    union {
276	struct exec ex;
277	Elf32_Ehdr eh;
278    } hdr;
279    Elf32_Phdr ep[2];
280    Elf32_Shdr es[2];
281    caddr_t p;
282    ino_t ino;
283    uint32_t addr, x;
284    int fmt, i, j;
285
286    if (!(ino = lookup(kname))) {
287	if (!ls)
288	    printf("No %s\n", kname);
289	return;
290    }
291    if (xfsread(ino, &hdr, sizeof(hdr)))
292	return;
293    if (N_GETMAGIC(hdr.ex) == ZMAGIC)
294	fmt = 0;
295    else if (IS_ELF(hdr.eh))
296	fmt = 1;
297    else {
298	printf("Invalid %s\n", "format");
299	return;
300    }
301    if (fmt == 0) {
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	p += hdr.ex.a_data + roundup2(hdr.ex.a_bss, PAGE_SIZE);
311	bootinfo.bi_symtab = VTOP(p);
312	memcpy(p, &hdr.ex.a_syms, sizeof(hdr.ex.a_syms));
313	p += sizeof(hdr.ex.a_syms);
314	if (hdr.ex.a_syms) {
315	    if (xfsread(ino, p, hdr.ex.a_syms))
316		return;
317	    p += hdr.ex.a_syms;
318	    if (xfsread(ino, p, sizeof(int)))
319		return;
320	    x = *(uint32_t *)p;
321	    p += sizeof(int);
322	    x -= sizeof(int);
323	    if (xfsread(ino, p, x))
324		return;
325	    p += x;
326	}
327    } else {
328	fs_off = hdr.eh.e_phoff;
329	for (j = i = 0; i < hdr.eh.e_phnum && j < 2; i++) {
330	    if (xfsread(ino, ep + j, sizeof(ep[0])))
331		return;
332	    if (ep[j].p_type == PT_LOAD)
333		j++;
334	}
335	for (i = 0; i < 2; i++) {
336	    p = PTOV(ep[i].p_paddr & 0xffffff);
337	    fs_off = ep[i].p_offset;
338	    if (xfsread(ino, p, ep[i].p_filesz))
339		return;
340	}
341	p += roundup2(ep[1].p_memsz, PAGE_SIZE);
342	bootinfo.bi_symtab = VTOP(p);
343	if (hdr.eh.e_shnum == hdr.eh.e_shstrndx + 3) {
344	    fs_off = hdr.eh.e_shoff + sizeof(es[0]) *
345		(hdr.eh.e_shstrndx + 1);
346	    if (xfsread(ino, &es, sizeof(es)))
347		return;
348	    for (i = 0; i < 2; i++) {
349		memcpy(p, &es[i].sh_size, sizeof(es[i].sh_size));
350		p += sizeof(es[i].sh_size);
351		fs_off = es[i].sh_offset;
352		if (xfsread(ino, p, es[i].sh_size))
353		    return;
354		p += es[i].sh_size;
355	    }
356	}
357	addr = hdr.eh.e_entry & 0xffffff;
358    }
359    bootinfo.bi_esymtab = VTOP(p);
360    bootinfo.bi_kernelname = VTOP(kname);
361    bootinfo.bi_bios_dev = dsk.drive;
362    __exec((caddr_t)addr, RB_BOOTINFO | (opts & RBX_MASK),
363	   MAKEBOOTDEV(dev_maj[dsk.type], 0, dsk.slice, dsk.unit, dsk.part),
364	   0, 0, 0, VTOP(&bootinfo));
365}
366
367static int
368parse()
369{
370    char *arg = cmd;
371    char *p, *q;
372    unsigned int drv;
373    int c, i;
374
375    while ((c = *arg++)) {
376	if (c == ' ' || c == '\t' || c == '\n')
377	    continue;
378	for (p = arg; *p && *p != '\n' && *p != ' ' && *p != '\t'; p++);
379	if (*p)
380	    *p++ = 0;
381	if (c == '-') {
382	    while ((c = *arg++)) {
383		for (i = 0; c != optstr[i]; i++)
384		    if (i == NOPT - 1)
385			return -1;
386		opts ^= 1 << flags[i];
387	    }
388	    if (opts & 1 << RBX_PROBEKBD) {
389		i = *(uint8_t *)PTOV(0x496) & 0x10;
390		printf("Keyboard: %s\n", i ? "yes" : "no");
391		if (!i)
392		    opts |= 1 << RBX_DUAL | 1 << RBX_SERIAL;
393		opts &= ~(1 << RBX_PROBEKBD);
394	    }
395	    ioctrl = opts & 1 << RBX_DUAL ? (IO_SERIAL|IO_KEYBOARD) :
396		     opts & 1 << RBX_SERIAL ? IO_SERIAL : IO_KEYBOARD;
397	    if (ioctrl & IO_SERIAL)
398	        sio_init();
399	} else {
400	    for (q = arg--; *q && *q != '('; q++);
401	    if (*q) {
402		drv = -1;
403		if (arg[1] == ':') {
404		    drv = *arg - '0';
405		    if (drv > 9)
406			return (-1);
407		    arg += 2;
408		}
409		if (q - arg != 2)
410		    return -1;
411		for (i = 0; arg[0] != dev_nm[i][0] ||
412			    arg[1] != dev_nm[i][1]; i++)
413		    if (i == NDEV - 1)
414			return -1;
415		dsk.type = i;
416		arg += 3;
417		dsk.unit = *arg - '0';
418		if (arg[1] != ',' || dsk.unit > 9)
419		    return -1;
420		arg += 2;
421		dsk.slice = WHOLE_DISK_SLICE;
422		if (arg[1] == ',') {
423		    dsk.slice = *arg - '0' + 1;
424		    if (dsk.slice > NDOSPART)
425			return -1;
426		    arg += 2;
427		}
428		if (arg[1] != ')')
429		    return -1;
430		dsk.part = *arg - 'a';
431		if (dsk.part > 7)
432		    return (-1);
433		arg += 2;
434		if (drv == -1)
435		    drv = dsk.unit;
436		dsk.drive = (dsk.type <= TYPE_MAXHARD
437			     ? DRV_HARD : 0) + drv;
438		dsk_meta = 0;
439	    }
440	    if ((i = p - arg - !*(p - 1))) {
441		if ((size_t)i >= sizeof(kname))
442		    return -1;
443		memcpy(kname, arg, i + 1);
444	    }
445	}
446	arg = p;
447    }
448    return 0;
449}
450
451static int
452dskread(void *buf, unsigned lba, unsigned nblk)
453{
454    struct dos_partition *dp;
455    struct disklabel *d;
456    char *sec;
457    unsigned sl, i;
458
459    if (!dsk_meta) {
460	sec = dmadat->secbuf;
461	dsk.start = 0;
462	if (drvread(sec, DOSBBSECTOR, 1))
463	    return -1;
464	dp = (void *)(sec + DOSPARTOFF);
465	sl = dsk.slice;
466	if (sl < BASE_SLICE) {
467	    for (i = 0; i < NDOSPART; i++)
468		if (dp[i].dp_typ == DOSPTYP_386BSD &&
469		    (dp[i].dp_flag & 0x80 || sl < BASE_SLICE)) {
470		    sl = BASE_SLICE + i;
471		    if (dp[i].dp_flag & 0x80 ||
472			dsk.slice == COMPATIBILITY_SLICE)
473			break;
474		}
475	    if (dsk.slice == WHOLE_DISK_SLICE)
476		dsk.slice = sl;
477	}
478	if (sl != WHOLE_DISK_SLICE) {
479	    if (sl != COMPATIBILITY_SLICE)
480		dp += sl - BASE_SLICE;
481	    if (dp->dp_typ != DOSPTYP_386BSD) {
482		printf("Invalid %s\n", "slice");
483		return -1;
484	    }
485	    dsk.start = dp->dp_start;
486	}
487	if (drvread(sec, dsk.start + LABELSECTOR, 1))
488		return -1;
489	d = (void *)(sec + LABELOFFSET);
490	if (d->d_magic != DISKMAGIC || d->d_magic2 != DISKMAGIC) {
491	    if (dsk.part != RAW_PART) {
492		printf("Invalid %s\n", "label");
493		return -1;
494	    }
495	} else {
496	    if (!dsk.init) {
497		if (d->d_type == DTYPE_SCSI)
498		    dsk.type = TYPE_DA;
499		dsk.init++;
500	    }
501	    if (dsk.part >= d->d_npartitions ||
502		!d->d_partitions[dsk.part].p_size) {
503		printf("Invalid %s\n", "partition");
504		return -1;
505	    }
506	    dsk.start += d->d_partitions[dsk.part].p_offset;
507	    dsk.start -= d->d_partitions[RAW_PART].p_offset;
508	}
509    }
510    return drvread(buf, dsk.start + lba, nblk);
511}
512
513static void
514printf(const char *fmt,...)
515{
516    va_list ap;
517    char buf[10];
518    char *s;
519    unsigned u;
520    int c;
521
522    va_start(ap, fmt);
523    while ((c = *fmt++)) {
524	if (c == '%') {
525	    c = *fmt++;
526	    switch (c) {
527	    case 'c':
528		putchar(va_arg(ap, int));
529		continue;
530	    case 's':
531		for (s = va_arg(ap, char *); *s; s++)
532		    putchar(*s);
533		continue;
534	    case 'u':
535		u = va_arg(ap, unsigned);
536		s = buf;
537		do
538		    *s++ = '0' + u % 10U;
539		while (u /= 10U);
540		while (--s >= buf)
541		    putchar(*s);
542		continue;
543	    }
544	}
545	putchar(c);
546    }
547    va_end(ap);
548    return;
549}
550
551static void
552putchar(int c)
553{
554    if (c == '\n')
555	xputc('\r');
556    xputc(c);
557}
558
559static int
560drvread(void *buf, unsigned lba, unsigned nblk)
561{
562    static unsigned c = 0x2d5c7c2f;
563
564    printf("%c\b", c = c << 8 | c >> 24);
565    v86.ctl = V86_ADDR | V86_CALLF | V86_FLAGS;
566    v86.addr = XREADORG;		/* call to xread in boot1 */
567    v86.es = VTOPSEG(buf);
568    v86.eax = lba;
569    v86.ebx = VTOPOFF(buf);
570    v86.ecx = lba >> 16;
571    v86.edx = nblk << 8 | dsk.drive;
572    v86int();
573    v86.ctl = V86_FLAGS;
574    if (V86_CY(v86.efl)) {
575	printf("error %u lba %u\n", v86.eax >> 8 & 0xff, lba);
576	return -1;
577    }
578    return 0;
579}
580
581static int
582keyhit(unsigned ticks)
583{
584    uint32_t t0, t1;
585
586    if (opts & 1 << RBX_NOINTR)
587	return 0;
588    t0 = 0;
589    for (;;) {
590	if (xgetc(1))
591	    return 1;
592	t1 = *(uint32_t *)PTOV(0x46c);
593	if (!t0)
594	    t0 = t1;
595	if (t1 < t0 || t1 >= t0 + ticks)
596	    return 0;
597    }
598}
599
600static int
601xputc(int c)
602{
603    if (ioctrl & IO_KEYBOARD)
604	putc(c);
605    if (ioctrl & IO_SERIAL)
606	sio_putc(c);
607    return c;
608}
609
610static int
611xgetc(int fn)
612{
613    if (opts & 1 << RBX_NOINTR)
614	return 0;
615    for (;;) {
616	if (ioctrl & IO_KEYBOARD && getc(1))
617	    return fn ? 1 : getc(0);
618	if (ioctrl & IO_SERIAL && sio_ischar())
619	    return fn ? 1 : sio_getc();
620	if (fn)
621	    return 0;
622    }
623}
624
625static int
626getc(int fn)
627{
628    v86.addr = 0x16;
629    v86.eax = fn << 8;
630    v86int();
631    return fn == 0 ? v86.eax & 0xff : !V86_ZR(v86.efl);
632}
633