xref: /freebsd-12.1/stand/i386/zfsboot/zfsboot.c (revision 3faa0c8e)
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("$FreeBSD$");
18 
19 #include "stand.h"
20 
21 #include <sys/param.h>
22 #include <sys/errno.h>
23 #include <sys/diskmbr.h>
24 #ifdef GPT
25 #include <sys/gpt.h>
26 #endif
27 #include <sys/reboot.h>
28 #include <sys/queue.h>
29 
30 #include <machine/bootinfo.h>
31 #include <machine/elf.h>
32 #include <machine/pc/bios.h>
33 
34 #include <stdarg.h>
35 #include <stddef.h>
36 
37 #include <a.out.h>
38 
39 #include <btxv86.h>
40 
41 #include "lib.h"
42 #include "rbx.h"
43 #include "drv.h"
44 #include "edd.h"
45 #include "cons.h"
46 #include "bootargs.h"
47 #include "paths.h"
48 
49 #include "libzfs.h"
50 
51 #define ARGS			0x900
52 #define NOPT			14
53 #define NDEV			3
54 
55 #define BIOS_NUMDRIVES		0x475
56 #define DRV_HARD		0x80
57 #define DRV_MASK		0x7f
58 
59 #define TYPE_AD			0
60 #define TYPE_DA			1
61 #define TYPE_MAXHARD		TYPE_DA
62 #define TYPE_FD			2
63 
64 #define DEV_GELIBOOT_BSIZE	4096
65 
66 extern uint32_t _end;
67 
68 #ifdef GPT
69 static const uuid_t freebsd_zfs_uuid = GPT_ENT_TYPE_FREEBSD_ZFS;
70 #endif
71 static const char optstr[NOPT] = "DhaCcdgmnpqrsv"; /* Also 'P', 'S' */
72 static const unsigned char flags[NOPT] = {
73     RBX_DUAL,
74     RBX_SERIAL,
75     RBX_ASKNAME,
76     RBX_CDROM,
77     RBX_CONFIG,
78     RBX_KDB,
79     RBX_GDB,
80     RBX_MUTE,
81     RBX_NOINTR,
82     RBX_PAUSE,
83     RBX_QUIET,
84     RBX_DFLTROOT,
85     RBX_SINGLE,
86     RBX_VERBOSE
87 };
88 uint32_t opts;
89 
90 /*
91  * Paths to try loading before falling back to the boot2 prompt.
92  *
93  * /boot/zfsloader must be tried before /boot/loader in order to remain
94  * backward compatible with ZFS boot environments where /boot/loader exists
95  * but does not have ZFS support, which was the case before FreeBSD 12.
96  *
97  * If no loader is found, try to load a kernel directly instead.
98  */
99 static const struct string {
100     const char *p;
101     size_t len;
102 } loadpath[] = {
103     { PATH_LOADER_ZFS, sizeof(PATH_LOADER_ZFS) },
104     { PATH_LOADER, sizeof(PATH_LOADER) },
105     { PATH_KERNEL, sizeof(PATH_KERNEL) },
106 };
107 
108 static const unsigned char dev_maj[NDEV] = {30, 4, 2};
109 
110 static char cmd[512];
111 static char cmddup[512];
112 static char kname[1024];
113 static char rootname[256];
114 static int comspeed = SIOSPD;
115 static struct bootinfo bootinfo;
116 static uint32_t bootdev;
117 static struct zfs_boot_args zfsargs;
118 
119 vm_offset_t	high_heap_base;
120 uint32_t	bios_basemem, bios_extmem, high_heap_size;
121 
122 static struct bios_smap smap;
123 
124 /*
125  * The minimum amount of memory to reserve in bios_extmem for the heap.
126  */
127 #define	HEAP_MIN		(64 * 1024 * 1024)
128 
129 static char *heap_next;
130 static char *heap_end;
131 
132 /* Buffers that must not span a 64k boundary. */
133 #define READ_BUF_SIZE		8192
134 struct dmadat {
135 	char rdbuf[READ_BUF_SIZE];	/* for reading large things */
136 	char secbuf[READ_BUF_SIZE];	/* for MBR/disklabel */
137 };
138 static struct dmadat *dmadat;
139 
140 void exit(int);
141 void reboot(void);
142 static void load(void);
143 static int parse_cmd(void);
144 static void bios_getmem(void);
145 int main(void);
146 
147 #ifdef LOADER_GELI_SUPPORT
148 #include "geliboot.h"
149 static char gelipw[GELI_PW_MAXLEN];
150 #endif
151 
152 struct zfsdsk {
153 	struct dsk       dsk;
154 #ifdef LOADER_GELI_SUPPORT
155 	struct geli_dev *gdev;
156 #endif
157 };
158 
159 #include "zfsimpl.c"
160 
161 /*
162  * Read from a dnode (which must be from a ZPL filesystem).
163  */
164 static int
zfs_read(spa_t * spa,const dnode_phys_t * dnode,off_t * offp,void * start,size_t size)165 zfs_read(spa_t *spa, const dnode_phys_t *dnode, off_t *offp, void *start, size_t size)
166 {
167 	const znode_phys_t *zp = (const znode_phys_t *) dnode->dn_bonus;
168 	size_t n;
169 	int rc;
170 
171 	n = size;
172 	if (*offp + n > zp->zp_size)
173 		n = zp->zp_size - *offp;
174 
175 	rc = dnode_read(spa, dnode, *offp, start, n);
176 	if (rc)
177 		return (-1);
178 	*offp += n;
179 
180 	return (n);
181 }
182 
183 /*
184  * Current ZFS pool
185  */
186 static spa_t *spa;
187 static spa_t *primary_spa;
188 static vdev_t *primary_vdev;
189 
190 /*
191  * A wrapper for dskread that doesn't have to worry about whether the
192  * buffer pointer crosses a 64k boundary.
193  */
194 static int
vdev_read(void * xvdev,void * priv,off_t off,void * buf,size_t bytes)195 vdev_read(void *xvdev, void *priv, off_t off, void *buf, size_t bytes)
196 {
197 	char *p;
198 	daddr_t lba, alignlba;
199 	off_t diff;
200 	unsigned int nb, alignnb;
201 	struct zfsdsk *zdsk = (struct zfsdsk *) priv;
202 
203 	if ((off & (DEV_BSIZE - 1)) || (bytes & (DEV_BSIZE - 1)))
204 		return -1;
205 
206 	p = buf;
207 	lba = off / DEV_BSIZE;
208 	lba += zdsk->dsk.start;
209 	/*
210 	 * Align reads to 4k else 4k sector GELIs will not decrypt.
211 	 * Round LBA down to nearest multiple of DEV_GELIBOOT_BSIZE bytes.
212 	 */
213 	alignlba = rounddown2(off, DEV_GELIBOOT_BSIZE) / DEV_BSIZE;
214 	/*
215 	 * The read must be aligned to DEV_GELIBOOT_BSIZE bytes relative to the
216 	 * start of the GELI partition, not the start of the actual disk.
217 	 */
218 	alignlba += zdsk->dsk.start;
219 	diff = (lba - alignlba) * DEV_BSIZE;
220 
221 	while (bytes > 0) {
222 		nb = bytes / DEV_BSIZE;
223 		/*
224 		 * Ensure that the read size plus the leading offset does not
225 		 * exceed the size of the read buffer.
226 		 */
227 		if (nb > (READ_BUF_SIZE - diff) / DEV_BSIZE)
228 			nb = (READ_BUF_SIZE - diff) / DEV_BSIZE;
229 		/*
230 		 * Round the number of blocks to read up to the nearest multiple
231 		 * of DEV_GELIBOOT_BSIZE.
232 		 */
233 		alignnb = roundup2(nb * DEV_BSIZE + diff, DEV_GELIBOOT_BSIZE)
234 		    / DEV_BSIZE;
235 
236 		if (zdsk->dsk.size > 0 && alignlba + alignnb >
237 		    zdsk->dsk.size + zdsk->dsk.start) {
238 			printf("Shortening read at %lld from %d to %lld\n",
239 			    alignlba, alignnb,
240 			    (zdsk->dsk.size + zdsk->dsk.start) - alignlba);
241 			alignnb = (zdsk->dsk.size + zdsk->dsk.start) - alignlba;
242 		}
243 
244 		if (drvread(&zdsk->dsk, dmadat->rdbuf, alignlba, alignnb))
245 			return -1;
246 #ifdef LOADER_GELI_SUPPORT
247 		/* decrypt */
248 		if (zdsk->gdev != NULL) {
249 			if (geli_read(zdsk->gdev, ((alignlba - zdsk->dsk.start) *
250 			    DEV_BSIZE), dmadat->rdbuf, alignnb * DEV_BSIZE))
251 				return (-1);
252 		}
253 #endif
254 		memcpy(p, dmadat->rdbuf + diff, nb * DEV_BSIZE);
255 		p += nb * DEV_BSIZE;
256 		lba += nb;
257 		alignlba += alignnb;
258 		bytes -= nb * DEV_BSIZE;
259 		/* Don't need the leading offset after the first block. */
260 		diff = 0;
261 	}
262 
263 	return 0;
264 }
265 /* Match the signature exactly due to signature madness */
266 static int
vdev_read2(vdev_t * vdev,void * priv,off_t off,void * buf,size_t bytes)267 vdev_read2(vdev_t *vdev, void *priv, off_t off, void *buf, size_t bytes)
268 {
269 	return vdev_read(vdev, priv, off, buf, bytes);
270 }
271 
272 
273 static int
vdev_write(vdev_t * vdev,void * priv,off_t off,void * buf,size_t bytes)274 vdev_write(vdev_t *vdev, void *priv, off_t off, void *buf, size_t bytes)
275 {
276 	char *p;
277 	daddr_t lba;
278 	unsigned int nb;
279 	struct zfsdsk *zdsk = (struct zfsdsk *) priv;
280 
281 	if ((off & (DEV_BSIZE - 1)) || (bytes & (DEV_BSIZE - 1)))
282 		return -1;
283 
284 	p = buf;
285 	lba = off / DEV_BSIZE;
286 	lba += zdsk->dsk.start;
287 	while (bytes > 0) {
288 		nb = bytes / DEV_BSIZE;
289 		if (nb > READ_BUF_SIZE / DEV_BSIZE)
290 			nb = READ_BUF_SIZE / DEV_BSIZE;
291 		memcpy(dmadat->rdbuf, p, nb * DEV_BSIZE);
292 		if (drvwrite(&zdsk->dsk, dmadat->rdbuf, lba, nb))
293 			return -1;
294 		p += nb * DEV_BSIZE;
295 		lba += nb;
296 		bytes -= nb * DEV_BSIZE;
297 	}
298 
299 	return 0;
300 }
301 
302 static int
xfsread(const dnode_phys_t * dnode,off_t * offp,void * buf,size_t nbyte)303 xfsread(const dnode_phys_t *dnode, off_t *offp, void *buf, size_t nbyte)
304 {
305     if ((size_t)zfs_read(spa, dnode, offp, buf, nbyte) != nbyte) {
306 	printf("Invalid format\n");
307 	return -1;
308     }
309     return 0;
310 }
311 
312 /*
313  * Read Pad2 (formerly "Boot Block Header") area of the first
314  * vdev label of the given vdev.
315  */
316 static int
vdev_read_pad2(vdev_t * vdev,char * buf,size_t size)317 vdev_read_pad2(vdev_t *vdev, char *buf, size_t size)
318 {
319 	blkptr_t bp;
320 	char *tmp = zap_scratch;
321 	off_t off = offsetof(vdev_label_t, vl_pad2);
322 
323 	if (size > VDEV_PAD_SIZE)
324 		size = VDEV_PAD_SIZE;
325 
326 	BP_ZERO(&bp);
327 	BP_SET_LSIZE(&bp, VDEV_PAD_SIZE);
328 	BP_SET_PSIZE(&bp, VDEV_PAD_SIZE);
329 	BP_SET_CHECKSUM(&bp, ZIO_CHECKSUM_LABEL);
330 	BP_SET_COMPRESS(&bp, ZIO_COMPRESS_OFF);
331 	DVA_SET_OFFSET(BP_IDENTITY(&bp), off);
332 	if (vdev_read_phys(vdev, &bp, tmp, off, 0))
333 		return (EIO);
334 	memcpy(buf, tmp, size);
335 	return (0);
336 }
337 
338 static int
vdev_clear_pad2(vdev_t * vdev)339 vdev_clear_pad2(vdev_t *vdev)
340 {
341 	char *zeroes = zap_scratch;
342 	uint64_t *end;
343 	off_t off = offsetof(vdev_label_t, vl_pad2);
344 
345 	memset(zeroes, 0, VDEV_PAD_SIZE);
346 	end = (uint64_t *)(zeroes + VDEV_PAD_SIZE);
347 	/* ZIO_CHECKSUM_LABEL magic and pre-calcualted checksum for all zeros */
348 	end[-5] = 0x0210da7ab10c7a11;
349 	end[-4] = 0x97f48f807f6e2a3f;
350 	end[-3] = 0xaf909f1658aacefc;
351 	end[-2] = 0xcbd1ea57ff6db48b;
352 	end[-1] = 0x6ec692db0d465fab;
353 	if (vdev_write(vdev, vdev->v_read_priv, off, zeroes, VDEV_PAD_SIZE))
354 		return (EIO);
355 	return (0);
356 }
357 
358 static void
bios_getmem(void)359 bios_getmem(void)
360 {
361     uint64_t size;
362 
363     /* Parse system memory map */
364     v86.ebx = 0;
365     do {
366 	v86.ctl = V86_FLAGS;
367 	v86.addr = 0x15;		/* int 0x15 function 0xe820*/
368 	v86.eax = 0xe820;
369 	v86.ecx = sizeof(struct bios_smap);
370 	v86.edx = SMAP_SIG;
371 	v86.es = VTOPSEG(&smap);
372 	v86.edi = VTOPOFF(&smap);
373 	v86int();
374 	if (V86_CY(v86.efl) || (v86.eax != SMAP_SIG))
375 	    break;
376 	/* look for a low-memory segment that's large enough */
377 	if ((smap.type == SMAP_TYPE_MEMORY) && (smap.base == 0) &&
378 	    (smap.length >= (512 * 1024)))
379 	    bios_basemem = smap.length;
380 	/* look for the first segment in 'extended' memory */
381 	if ((smap.type == SMAP_TYPE_MEMORY) && (smap.base == 0x100000)) {
382 	    bios_extmem = smap.length;
383 	}
384 
385 	/*
386 	 * Look for the largest segment in 'extended' memory beyond
387 	 * 1MB but below 4GB.
388 	 */
389 	if ((smap.type == SMAP_TYPE_MEMORY) && (smap.base > 0x100000) &&
390 	    (smap.base < 0x100000000ull)) {
391 	    size = smap.length;
392 
393 	    /*
394 	     * If this segment crosses the 4GB boundary, truncate it.
395 	     */
396 	    if (smap.base + size > 0x100000000ull)
397 		size = 0x100000000ull - smap.base;
398 
399 	    if (size > high_heap_size) {
400 		high_heap_size = size;
401 		high_heap_base = smap.base;
402 	    }
403 	}
404     } while (v86.ebx != 0);
405 
406     /* Fall back to the old compatibility function for base memory */
407     if (bios_basemem == 0) {
408 	v86.ctl = 0;
409 	v86.addr = 0x12;		/* int 0x12 */
410 	v86int();
411 
412 	bios_basemem = (v86.eax & 0xffff) * 1024;
413     }
414 
415     /* Fall back through several compatibility functions for extended memory */
416     if (bios_extmem == 0) {
417 	v86.ctl = V86_FLAGS;
418 	v86.addr = 0x15;		/* int 0x15 function 0xe801*/
419 	v86.eax = 0xe801;
420 	v86int();
421 	if (!V86_CY(v86.efl)) {
422 	    bios_extmem = ((v86.ecx & 0xffff) + ((v86.edx & 0xffff) * 64)) * 1024;
423 	}
424     }
425     if (bios_extmem == 0) {
426 	v86.ctl = 0;
427 	v86.addr = 0x15;		/* int 0x15 function 0x88*/
428 	v86.eax = 0x8800;
429 	v86int();
430 	bios_extmem = (v86.eax & 0xffff) * 1024;
431     }
432 
433     /*
434      * If we have extended memory and did not find a suitable heap
435      * region in the SMAP, use the last 3MB of 'extended' memory as a
436      * high heap candidate.
437      */
438     if (bios_extmem >= HEAP_MIN && high_heap_size < HEAP_MIN) {
439 	high_heap_size = HEAP_MIN;
440 	high_heap_base = bios_extmem + 0x100000 - HEAP_MIN;
441     }
442 }
443 
444 /*
445  * Try to detect a device supported by the legacy int13 BIOS
446  */
447 static int
int13probe(int drive)448 int13probe(int drive)
449 {
450     v86.ctl = V86_FLAGS;
451     v86.addr = 0x13;
452     v86.eax = 0x800;
453     v86.edx = drive;
454     v86int();
455 
456     if (!V86_CY(v86.efl) &&				/* carry clear */
457 	((v86.edx & 0xff) != (drive & DRV_MASK))) {	/* unit # OK */
458 	if ((v86.ecx & 0x3f) == 0) {			/* absurd sector size */
459 		return(0);				/* skip device */
460 	}
461 	return (1);
462     }
463     return(0);
464 }
465 
466 /*
467  * We call this when we find a ZFS vdev - ZFS consumes the dsk
468  * structure so we must make a new one.
469  */
470 static struct zfsdsk *
copy_dsk(struct zfsdsk * zdsk)471 copy_dsk(struct zfsdsk *zdsk)
472 {
473     struct zfsdsk *newdsk;
474 
475     newdsk = malloc(sizeof(struct zfsdsk));
476     *newdsk = *zdsk;
477     return (newdsk);
478 }
479 
480 /*
481  * Get disk size from eax=0x800 and 0x4800. We need to probe both
482  * because 0x4800 may not be available and we would like to get more
483  * or less correct disk size - if it is possible at all.
484  * Note we do not really want to touch drv.c because that code is shared
485  * with boot2 and we can not afford to grow that code.
486  */
487 static uint64_t
drvsize_ext(struct zfsdsk * zdsk)488 drvsize_ext(struct zfsdsk *zdsk)
489 {
490 	struct dsk *dskp;
491 	uint64_t size, tmp;
492 	int cyl, hds, sec;
493 
494 	dskp = &zdsk->dsk;
495 
496 	v86.ctl = V86_FLAGS;
497 	v86.addr = 0x13;
498 	v86.eax = 0x800;
499 	v86.edx = dskp->drive;
500 	v86int();
501 
502 	/* Don't error out if we get bad sector number, try EDD as well */
503 	if (V86_CY(v86.efl) ||	/* carry set */
504 	    (v86.edx & 0xff) <= (unsigned)(dskp->drive & 0x7f)) /* unit # bad */
505 		return (0);
506 	cyl = ((v86.ecx & 0xc0) << 2) + ((v86.ecx & 0xff00) >> 8) + 1;
507 	/* Convert max head # -> # of heads */
508 	hds = ((v86.edx & 0xff00) >> 8) + 1;
509 	sec = v86.ecx & 0x3f;
510 
511 	size = (uint64_t)cyl * hds * sec;
512 
513 	/* Determine if we can use EDD with this device. */
514 	v86.ctl = V86_FLAGS;
515 	v86.addr = 0x13;
516 	v86.eax = 0x4100;
517 	v86.edx = dskp->drive;
518 	v86.ebx = 0x55aa;
519 	v86int();
520 	if (V86_CY(v86.efl) ||  /* carry set */
521 	    (v86.ebx & 0xffff) != 0xaa55 || /* signature */
522 	    (v86.ecx & EDD_INTERFACE_FIXED_DISK) == 0)
523 		return (size);
524 
525 	tmp = drvsize(dskp);
526 	if (tmp > size)
527 		size = tmp;
528 
529 	return (size);
530 }
531 
532 /*
533  * The "layered" ioctl to read disk/partition size. Unfortunately
534  * the zfsboot case is hardest, because we do not have full software
535  * stack available, so we need to do some manual work here.
536  */
537 uint64_t
ldi_get_size(void * priv)538 ldi_get_size(void *priv)
539 {
540 	struct zfsdsk *zdsk = priv;
541 	uint64_t size = zdsk->dsk.size;
542 
543 	if (zdsk->dsk.start == 0)
544 		size = drvsize_ext(zdsk);
545 
546 	return (size * DEV_BSIZE);
547 }
548 
549 static void
probe_drive(struct zfsdsk * zdsk)550 probe_drive(struct zfsdsk *zdsk)
551 {
552 #ifdef GPT
553     struct gpt_hdr hdr;
554     struct gpt_ent *ent;
555     unsigned part, entries_per_sec;
556     daddr_t slba;
557 #endif
558 #if defined(GPT) || defined(LOADER_GELI_SUPPORT)
559     daddr_t elba;
560 #endif
561 
562     struct dos_partition *dp;
563     char *sec;
564     unsigned i;
565 
566     /*
567      * If we find a vdev on the whole disk, stop here.
568      */
569     if (vdev_probe(vdev_read2, zdsk, NULL) == 0)
570 	return;
571 
572 #ifdef LOADER_GELI_SUPPORT
573     /*
574      * Taste the disk, if it is GELI encrypted, decrypt it and check to see if
575      * it is a usable vdev then. Otherwise dig
576      * out the partition table and probe each slice/partition
577      * in turn for a vdev or GELI encrypted vdev.
578      */
579     elba = drvsize_ext(zdsk);
580     if (elba > 0) {
581 	elba--;
582     }
583     zdsk->gdev = geli_taste(vdev_read, zdsk, elba, "disk%u:0:");
584     if (zdsk->gdev != NULL) {
585 	if (geli_havekey(zdsk->gdev) == 0 ||
586 	    geli_passphrase(zdsk->gdev, gelipw) == 0) {
587 	    if (vdev_probe(vdev_read2, zdsk, NULL) == 0) {
588 		return;
589 	    }
590 	}
591     }
592 #endif /* LOADER_GELI_SUPPORT */
593 
594     sec = dmadat->secbuf;
595     zdsk->dsk.start = 0;
596 
597 #ifdef GPT
598     /*
599      * First check for GPT.
600      */
601     if (drvread(&zdsk->dsk, sec, 1, 1)) {
602 	return;
603     }
604     memcpy(&hdr, sec, sizeof(hdr));
605     if (memcmp(hdr.hdr_sig, GPT_HDR_SIG, sizeof(hdr.hdr_sig)) != 0 ||
606 	hdr.hdr_lba_self != 1 || hdr.hdr_revision < 0x00010000 ||
607 	hdr.hdr_entsz < sizeof(*ent) || DEV_BSIZE % hdr.hdr_entsz != 0) {
608 	goto trymbr;
609     }
610 
611     /*
612      * Probe all GPT partitions for the presence of ZFS pools. We
613      * return the spa_t for the first we find (if requested). This
614      * will have the effect of booting from the first pool on the
615      * disk.
616      *
617      * If no vdev is found, GELI decrypting the device and try again
618      */
619     entries_per_sec = DEV_BSIZE / hdr.hdr_entsz;
620     slba = hdr.hdr_lba_table;
621     elba = slba + hdr.hdr_entries / entries_per_sec;
622     while (slba < elba) {
623 	zdsk->dsk.start = 0;
624 	if (drvread(&zdsk->dsk, sec, slba, 1))
625 	    return;
626 	for (part = 0; part < entries_per_sec; part++) {
627 	    ent = (struct gpt_ent *)(sec + part * hdr.hdr_entsz);
628 	    if (memcmp(&ent->ent_type, &freebsd_zfs_uuid,
629 		     sizeof(uuid_t)) == 0) {
630 		zdsk->dsk.start = ent->ent_lba_start;
631 		zdsk->dsk.size = ent->ent_lba_end - ent->ent_lba_start + 1;
632 		zdsk->dsk.slice = part + 1;
633 		zdsk->dsk.part = 255;
634 		if (vdev_probe(vdev_read2, zdsk, NULL) == 0) {
635 		    /*
636 		     * This slice had a vdev. We need a new dsk
637 		     * structure now since the vdev now owns this one.
638 		     */
639 		    zdsk = copy_dsk(zdsk);
640 		}
641 #ifdef LOADER_GELI_SUPPORT
642 		else if ((zdsk->gdev = geli_taste(vdev_read, zdsk,
643 		    ent->ent_lba_end - ent->ent_lba_start, "disk%up%u:",
644 		    zdsk->dsk.unit, zdsk->dsk.slice)) != NULL) {
645 		    if (geli_havekey(zdsk->gdev) == 0 ||
646 			geli_passphrase(zdsk->gdev, gelipw) == 0) {
647 			/*
648 			 * This slice has GELI, check it for ZFS.
649 			 */
650 			if (vdev_probe(vdev_read2, zdsk, NULL) == 0) {
651 			    /*
652 			     * This slice had a vdev. We need a new dsk
653 			     * structure now since the vdev now owns this one.
654 			     */
655 			    zdsk = copy_dsk(zdsk);
656 			}
657 			break;
658 		    }
659 		}
660 #endif /* LOADER_GELI_SUPPORT */
661 	    }
662 	}
663 	slba++;
664     }
665     return;
666 trymbr:
667 #endif /* GPT */
668 
669     if (drvread(&zdsk->dsk, sec, DOSBBSECTOR, 1))
670 	return;
671     dp = (void *)(sec + DOSPARTOFF);
672 
673     for (i = 0; i < NDOSPART; i++) {
674 	if (!dp[i].dp_typ)
675 	    continue;
676 	zdsk->dsk.start = dp[i].dp_start;
677 	zdsk->dsk.size = dp[i].dp_size;
678 	zdsk->dsk.slice = i + 1;
679 	if (vdev_probe(vdev_read2, zdsk, NULL) == 0) {
680 	    zdsk = copy_dsk(zdsk);
681 	}
682 #ifdef LOADER_GELI_SUPPORT
683 	else if ((zdsk->gdev = geli_taste(vdev_read, zdsk, dp[i].dp_size -
684 		 dp[i].dp_start, "disk%us%u:")) != NULL) {
685 	    if (geli_havekey(zdsk->gdev) == 0 ||
686 		geli_passphrase(zdsk->gdev, gelipw) == 0) {
687 		/*
688 		 * This slice has GELI, check it for ZFS.
689 		 */
690 		if (vdev_probe(vdev_read2, zdsk, NULL) == 0) {
691 		    /*
692 		     * This slice had a vdev. We need a new dsk
693 		     * structure now since the vdev now owns this one.
694 		     */
695 		    zdsk = copy_dsk(zdsk);
696 		}
697 		break;
698 	    }
699 	}
700 #endif /* LOADER_GELI_SUPPORT */
701     }
702 }
703 
704 int
main(void)705 main(void)
706 {
707     dnode_phys_t dn;
708     off_t off;
709     struct zfsdsk *zdsk;
710     int autoboot, i;
711     int nextboot;
712     int rc;
713 
714     dmadat = (void *)(roundup2(__base + (int32_t)&_end, 0x10000) - __base);
715 
716     bios_getmem();
717 
718     if (high_heap_size > 0) {
719 	heap_end = PTOV(high_heap_base + high_heap_size);
720 	heap_next = PTOV(high_heap_base);
721     } else {
722 	heap_next = (char *)dmadat + sizeof(*dmadat);
723 	heap_end = (char *)PTOV(bios_basemem);
724     }
725     setheap(heap_next, heap_end);
726 
727     zdsk = calloc(1, sizeof(struct zfsdsk));
728     zdsk->dsk.drive = *(uint8_t *)PTOV(ARGS);
729     zdsk->dsk.type = zdsk->dsk.drive & DRV_HARD ? TYPE_AD : TYPE_FD;
730     zdsk->dsk.unit = zdsk->dsk.drive & DRV_MASK;
731     zdsk->dsk.slice = *(uint8_t *)PTOV(ARGS + 1) + 1;
732     zdsk->dsk.part = 0;
733     zdsk->dsk.start = 0;
734     zdsk->dsk.size = drvsize_ext(zdsk);
735 
736     bootinfo.bi_version = BOOTINFO_VERSION;
737     bootinfo.bi_size = sizeof(bootinfo);
738     bootinfo.bi_basemem = bios_basemem / 1024;
739     bootinfo.bi_extmem = bios_extmem / 1024;
740     bootinfo.bi_memsizes_valid++;
741     bootinfo.bi_bios_dev = zdsk->dsk.drive;
742 
743     bootdev = MAKEBOOTDEV(dev_maj[zdsk->dsk.type],
744 			  zdsk->dsk.slice, zdsk->dsk.unit, zdsk->dsk.part);
745 
746     /* Process configuration file */
747 
748     autoboot = 1;
749 
750     zfs_init();
751 
752     /*
753      * Probe the boot drive first - we will try to boot from whatever
754      * pool we find on that drive.
755      */
756     probe_drive(zdsk);
757 
758     /*
759      * Probe the rest of the drives that the bios knows about. This
760      * will find any other available pools and it may fill in missing
761      * vdevs for the boot pool.
762      */
763 #ifndef VIRTUALBOX
764     for (i = 0; i < *(unsigned char *)PTOV(BIOS_NUMDRIVES); i++)
765 #else
766     for (i = 0; i < MAXBDDEV; i++)
767 #endif
768     {
769 	if ((i | DRV_HARD) == *(uint8_t *)PTOV(ARGS))
770 	    continue;
771 
772 	if (!int13probe(i | DRV_HARD))
773 	    break;
774 
775 	zdsk = calloc(1, sizeof(struct zfsdsk));
776 	zdsk->dsk.drive = i | DRV_HARD;
777 	zdsk->dsk.type = zdsk->dsk.drive & TYPE_AD;
778 	zdsk->dsk.unit = i;
779 	zdsk->dsk.slice = 0;
780 	zdsk->dsk.part = 0;
781 	zdsk->dsk.start = 0;
782 	zdsk->dsk.size = drvsize_ext(zdsk);
783 	probe_drive(zdsk);
784     }
785 
786     /*
787      * The first discovered pool, if any, is the pool.
788      */
789     spa = spa_get_primary();
790     if (!spa) {
791 	printf("%s: No ZFS pools located, can't boot\n", BOOTPROG);
792 	for (;;)
793 	    ;
794     }
795 
796     primary_spa = spa;
797     primary_vdev = spa_get_primary_vdev(spa);
798 
799     nextboot = 0;
800     rc  = vdev_read_pad2(primary_vdev, cmd, sizeof(cmd));
801     if (vdev_clear_pad2(primary_vdev))
802 	printf("failed to clear pad2 area of primary vdev\n");
803     if (rc == 0) {
804 	if (*cmd) {
805 	    /*
806 	     * We could find an old-style ZFS Boot Block header here.
807 	     * Simply ignore it.
808 	     */
809 	    if (*(uint64_t *)cmd != 0x2f5b007b10c) {
810 		/*
811 		 * Note that parse() is destructive to cmd[] and we also want
812 		 * to honor RBX_QUIET option that could be present in cmd[].
813 		 */
814 		nextboot = 1;
815 		memcpy(cmddup, cmd, sizeof(cmd));
816 		if (parse_cmd()) {
817 		    printf("failed to parse pad2 area of primary vdev\n");
818 		    reboot();
819 		}
820 		if (!OPT_CHECK(RBX_QUIET))
821 		    printf("zfs nextboot: %s\n", cmddup);
822 	    }
823 	    /* Do not process this command twice */
824 	    *cmd = 0;
825 	}
826     } else
827 	printf("failed to read pad2 area of primary vdev\n");
828 
829     /* Mount ZFS only if it's not already mounted via nextboot parsing. */
830     if (zfsmount.spa == NULL &&
831 	(zfs_spa_init(spa) != 0 || zfs_mount(spa, 0, &zfsmount) != 0)) {
832 	printf("%s: failed to mount default pool %s\n",
833 	    BOOTPROG, spa->spa_name);
834 	autoboot = 0;
835     } else if (zfs_lookup(&zfsmount, PATH_CONFIG, &dn) == 0 ||
836         zfs_lookup(&zfsmount, PATH_DOTCONFIG, &dn) == 0) {
837 	off = 0;
838 	zfs_read(spa, &dn, &off, cmd, sizeof(cmd));
839     }
840 
841     if (*cmd) {
842 	/*
843 	 * Note that parse_cmd() is destructive to cmd[] and we also want
844 	 * to honor RBX_QUIET option that could be present in cmd[].
845 	 */
846 	memcpy(cmddup, cmd, sizeof(cmd));
847 	if (parse_cmd())
848 	    autoboot = 0;
849 	if (!OPT_CHECK(RBX_QUIET))
850 	    printf("%s: %s\n", PATH_CONFIG, cmddup);
851 	/* Do not process this command twice */
852 	*cmd = 0;
853     }
854 
855     /* Do not risk waiting at the prompt forever. */
856     if (nextboot && !autoboot)
857 	reboot();
858 
859     if (autoboot && !*kname) {
860 	/*
861 	 * Iterate through the list of loader and kernel paths, trying to load.
862 	 * If interrupted by a keypress, or in case of failure, drop the user
863 	 * to the boot2 prompt.
864 	 */
865 	for (i = 0; i < nitems(loadpath); i++) {
866 	    memcpy(kname, loadpath[i].p, loadpath[i].len);
867 	    if (keyhit(3))
868 		break;
869 	    load();
870 	}
871     }
872 
873     /* Present the user with the boot2 prompt. */
874 
875     for (;;) {
876 	if (!autoboot || !OPT_CHECK(RBX_QUIET)) {
877 	    printf("\nFreeBSD/x86 boot\n");
878 	    if (zfs_rlookup(spa, zfsmount.rootobj, rootname) != 0)
879 		printf("Default: %s/<0x%llx>:%s\n"
880 		       "boot: ",
881 		       spa->spa_name, zfsmount.rootobj, kname);
882 	    else if (rootname[0] != '\0')
883 		printf("Default: %s/%s:%s\n"
884 		       "boot: ",
885 		       spa->spa_name, rootname, kname);
886 	    else
887 		printf("Default: %s:%s\n"
888 		       "boot: ",
889 		       spa->spa_name, kname);
890 	}
891 	if (ioctrl & IO_SERIAL)
892 	    sio_flush();
893 	if (!autoboot || keyhit(5))
894 	    getstr(cmd, sizeof(cmd));
895 	else if (!autoboot || !OPT_CHECK(RBX_QUIET))
896 	    putchar('\n');
897 	autoboot = 0;
898 	if (parse_cmd())
899 	    putchar('\a');
900 	else
901 	    load();
902     }
903 }
904 
905 /* XXX - Needed for btxld to link the boot2 binary; do not remove. */
906 void
exit(int x)907 exit(int x)
908 {
909     __exit(x);
910 }
911 
912 void
reboot(void)913 reboot(void)
914 {
915     __exit(0);
916 }
917 
918 static void
load(void)919 load(void)
920 {
921     union {
922 	struct exec ex;
923 	Elf32_Ehdr eh;
924     } hdr;
925     static Elf32_Phdr ep[2];
926     static Elf32_Shdr es[2];
927     caddr_t p;
928     dnode_phys_t dn;
929     off_t off;
930     uint32_t addr, x;
931     int fmt, i, j;
932 
933     if (zfs_lookup(&zfsmount, kname, &dn)) {
934 	printf("\nCan't find %s\n", kname);
935 	return;
936     }
937     off = 0;
938     if (xfsread(&dn, &off, &hdr, sizeof(hdr)))
939 	return;
940     if (N_GETMAGIC(hdr.ex) == ZMAGIC)
941 	fmt = 0;
942     else if (IS_ELF(hdr.eh))
943 	fmt = 1;
944     else {
945 	printf("Invalid %s\n", "format");
946 	return;
947     }
948     if (fmt == 0) {
949 	addr = hdr.ex.a_entry & 0xffffff;
950 	p = PTOV(addr);
951 	off = PAGE_SIZE;
952 	if (xfsread(&dn, &off, p, hdr.ex.a_text))
953 	    return;
954 	p += roundup2(hdr.ex.a_text, PAGE_SIZE);
955 	if (xfsread(&dn, &off, p, hdr.ex.a_data))
956 	    return;
957 	p += hdr.ex.a_data + roundup2(hdr.ex.a_bss, PAGE_SIZE);
958 	bootinfo.bi_symtab = VTOP(p);
959 	memcpy(p, &hdr.ex.a_syms, sizeof(hdr.ex.a_syms));
960 	p += sizeof(hdr.ex.a_syms);
961 	if (hdr.ex.a_syms) {
962 	    if (xfsread(&dn, &off, p, hdr.ex.a_syms))
963 		return;
964 	    p += hdr.ex.a_syms;
965 	    if (xfsread(&dn, &off, p, sizeof(int)))
966 		return;
967 	    x = *(uint32_t *)p;
968 	    p += sizeof(int);
969 	    x -= sizeof(int);
970 	    if (xfsread(&dn, &off, p, x))
971 		return;
972 	    p += x;
973 	}
974     } else {
975 	off = hdr.eh.e_phoff;
976 	for (j = i = 0; i < hdr.eh.e_phnum && j < 2; i++) {
977 	    if (xfsread(&dn, &off, ep + j, sizeof(ep[0])))
978 		return;
979 	    if (ep[j].p_type == PT_LOAD)
980 		j++;
981 	}
982 	for (i = 0; i < 2; i++) {
983 	    p = PTOV(ep[i].p_paddr & 0xffffff);
984 	    off = ep[i].p_offset;
985 	    if (xfsread(&dn, &off, p, ep[i].p_filesz))
986 		return;
987 	}
988 	p += roundup2(ep[1].p_memsz, PAGE_SIZE);
989 	bootinfo.bi_symtab = VTOP(p);
990 	if (hdr.eh.e_shnum == hdr.eh.e_shstrndx + 3) {
991 	    off = hdr.eh.e_shoff + sizeof(es[0]) *
992 		(hdr.eh.e_shstrndx + 1);
993 	    if (xfsread(&dn, &off, &es, sizeof(es)))
994 		return;
995 	    for (i = 0; i < 2; i++) {
996 		memcpy(p, &es[i].sh_size, sizeof(es[i].sh_size));
997 		p += sizeof(es[i].sh_size);
998 		off = es[i].sh_offset;
999 		if (xfsread(&dn, &off, p, es[i].sh_size))
1000 		    return;
1001 		p += es[i].sh_size;
1002 	    }
1003 	}
1004 	addr = hdr.eh.e_entry & 0xffffff;
1005     }
1006     bootinfo.bi_esymtab = VTOP(p);
1007     bootinfo.bi_kernelname = VTOP(kname);
1008     zfsargs.size = sizeof(zfsargs);
1009     zfsargs.pool = zfsmount.spa->spa_guid;
1010     zfsargs.root = zfsmount.rootobj;
1011     zfsargs.primary_pool = primary_spa->spa_guid;
1012 #ifdef LOADER_GELI_SUPPORT
1013     explicit_bzero(gelipw, sizeof(gelipw));
1014     export_geli_boot_data(&zfsargs.gelidata);
1015 #endif
1016     if (primary_vdev != NULL)
1017 	zfsargs.primary_vdev = primary_vdev->v_guid;
1018     else
1019 	printf("failed to detect primary vdev\n");
1020     /*
1021      * Note that the zfsargs struct is passed by value, not by pointer.  Code in
1022      * btxldr.S copies the values from the entry stack to a fixed location
1023      * within loader(8) at startup due to the presence of KARGS_FLAGS_EXTARG.
1024      */
1025     __exec((caddr_t)addr, RB_BOOTINFO | (opts & RBX_MASK),
1026 	   bootdev,
1027 	   KARGS_FLAGS_ZFS | KARGS_FLAGS_EXTARG,
1028 	   (uint32_t) spa->spa_guid,
1029 	   (uint32_t) (spa->spa_guid >> 32),
1030 	   VTOP(&bootinfo),
1031 	   zfsargs);
1032 }
1033 
1034 static int
zfs_mount_ds(char * dsname)1035 zfs_mount_ds(char *dsname)
1036 {
1037     uint64_t newroot;
1038     spa_t *newspa;
1039     char *q;
1040 
1041     q = strchr(dsname, '/');
1042     if (q)
1043 	*q++ = '\0';
1044     newspa = spa_find_by_name(dsname);
1045     if (newspa == NULL) {
1046 	printf("\nCan't find ZFS pool %s\n", dsname);
1047 	return -1;
1048     }
1049 
1050     if (zfs_spa_init(newspa))
1051 	return -1;
1052 
1053     newroot = 0;
1054     if (q) {
1055 	if (zfs_lookup_dataset(newspa, q, &newroot)) {
1056 	    printf("\nCan't find dataset %s in ZFS pool %s\n",
1057 		    q, newspa->spa_name);
1058 	    return -1;
1059 	}
1060     }
1061     if (zfs_mount(newspa, newroot, &zfsmount)) {
1062 	printf("\nCan't mount ZFS dataset\n");
1063 	return -1;
1064     }
1065     spa = newspa;
1066     return (0);
1067 }
1068 
1069 static int
parse_cmd(void)1070 parse_cmd(void)
1071 {
1072     char *arg = cmd;
1073     char *ep, *p, *q;
1074     const char *cp;
1075     int c, i, j;
1076 
1077     while ((c = *arg++)) {
1078 	if (c == ' ' || c == '\t' || c == '\n')
1079 	    continue;
1080 	for (p = arg; *p && *p != '\n' && *p != ' ' && *p != '\t'; p++);
1081 	ep = p;
1082 	if (*p)
1083 	    *p++ = 0;
1084 	if (c == '-') {
1085 	    while ((c = *arg++)) {
1086 		if (c == 'P') {
1087 		    if (*(uint8_t *)PTOV(0x496) & 0x10) {
1088 			cp = "yes";
1089 		    } else {
1090 			opts |= OPT_SET(RBX_DUAL) | OPT_SET(RBX_SERIAL);
1091 			cp = "no";
1092 		    }
1093 		    printf("Keyboard: %s\n", cp);
1094 		    continue;
1095 		} else if (c == 'S') {
1096 		    j = 0;
1097 		    while ((unsigned int)(i = *arg++ - '0') <= 9)
1098 			j = j * 10 + i;
1099 		    if (j > 0 && i == -'0') {
1100 			comspeed = j;
1101 			break;
1102 		    }
1103 		    /* Fall through to error below ('S' not in optstr[]). */
1104 		}
1105 		for (i = 0; c != optstr[i]; i++)
1106 		    if (i == NOPT - 1)
1107 			return -1;
1108 		opts ^= OPT_SET(flags[i]);
1109 	    }
1110 	    ioctrl = OPT_CHECK(RBX_DUAL) ? (IO_SERIAL|IO_KEYBOARD) :
1111 		     OPT_CHECK(RBX_SERIAL) ? IO_SERIAL : IO_KEYBOARD;
1112 	    if (ioctrl & IO_SERIAL) {
1113 	        if (sio_init(115200 / comspeed) != 0)
1114 		    ioctrl &= ~IO_SERIAL;
1115 	    }
1116 	} if (c == '?') {
1117 	    dnode_phys_t dn;
1118 
1119 	    if (zfs_lookup(&zfsmount, arg, &dn) == 0) {
1120 		zap_list(spa, &dn);
1121 	    }
1122 	    return -1;
1123 	} else {
1124 	    arg--;
1125 
1126 	    /*
1127 	     * Report pool status if the comment is 'status'. Lets
1128 	     * hope no-one wants to load /status as a kernel.
1129 	     */
1130 	    if (!strcmp(arg, "status")) {
1131 		spa_all_status();
1132 		return -1;
1133 	    }
1134 
1135 	    /*
1136 	     * If there is "zfs:" prefix simply ignore it.
1137 	     */
1138 	    if (strncmp(arg, "zfs:", 4) == 0)
1139 		arg += 4;
1140 
1141 	    /*
1142 	     * If there is a colon, switch pools.
1143 	     */
1144 	    q = strchr(arg, ':');
1145 	    if (q) {
1146 		*q++ = '\0';
1147 		if (zfs_mount_ds(arg) != 0)
1148 		    return -1;
1149 		arg = q;
1150 	    }
1151 	    if ((i = ep - arg)) {
1152 		if ((size_t)i >= sizeof(kname))
1153 		    return -1;
1154 		memcpy(kname, arg, i + 1);
1155 	    }
1156 	}
1157 	arg = p;
1158     }
1159     return 0;
1160 }
1161