1 /* ----------------------------------------------------------------------- *
3 * Copyright 2003-2009 H. Peter Anvin - All Rights Reserved
4 * Copyright 2009-2010 Intel Corporation; author: H. Peter Anvin
5 * Copyright 2010 Shao Miller
6 * Copyright 2010 Michal Soltys
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation, Inc., 53 Temple Place Ste 330,
11 * Boston MA 02111-1307, USA; either version 2 of the License, or
12 * (at your option) any later version; incorporated herein by reference.
14 * ----------------------------------------------------------------------- */
17 * Please see doc/chain.txt for the detailed documentation.
32 #include <syslinux/loadfile.h>
33 #include <syslinux/bootrm.h>
34 #include <syslinux/config.h>
35 #include <syslinux/disk.h>
36 #include <syslinux/video.h>
44 static int fixed_cnt
= 128; /* see comments in main() */
46 static int overlap(const struct data_area
*a
, const struct data_area
*b
)
49 a
->base
+ a
->size
> b
->base
&&
50 b
->base
+ b
->size
> a
->base
;
53 static int is_phys(uint8_t sdifs
)
56 sdifs
== SYSLINUX_FS_SYSLINUX
||
57 sdifs
== SYSLINUX_FS_EXTLINUX
||
58 sdifs
== SYSLINUX_FS_ISOLINUX
;
62 * Search for a specific drive, based on the MBR signature.
63 * Return drive and iterator at 0th position.
65 static int find_by_sig(uint32_t mbr_sig
,
66 struct part_iter
**_boot_part
)
68 struct part_iter
*boot_part
= NULL
;
69 struct disk_info diskinfo
;
72 for (drive
= 0x80; drive
< 0x80 + fixed_cnt
; drive
++) {
73 if (disk_get_params(drive
, &diskinfo
))
74 continue; /* Drive doesn't exist */
75 if (!(boot_part
= pi_begin(&diskinfo
, 0)))
77 /* Check for a MBR disk */
78 if (boot_part
->type
!= typedos
) {
82 if (boot_part
->sub
.dos
.disk_sig
== mbr_sig
) {
88 *_boot_part
= boot_part
;
93 * Search for a specific drive/partition, based on the GPT GUID.
94 * Return drive and iterator at proper position.
96 static int find_by_guid(const struct guid
*gpt_guid
,
97 struct part_iter
**_boot_part
)
99 struct part_iter
*boot_part
= NULL
;
100 struct disk_info diskinfo
;
103 for (drive
= 0x80; drive
< 0x80 + fixed_cnt
; drive
++) {
104 if (disk_get_params(drive
, &diskinfo
))
105 continue; /* Drive doesn't exist */
106 if (!(boot_part
= pi_begin(&diskinfo
, 0)))
108 /* Check for a GPT disk */
109 if (boot_part
->type
!= typegpt
) {
113 /* Check for a matching GPT disk guid */
114 if (!memcmp(&boot_part
->sub
.gpt
.disk_guid
, gpt_guid
, sizeof(*gpt_guid
))) {
117 /* disk guid doesn't match, maybe partition guid will */
118 while (!pi_next(&boot_part
)) {
119 if (!memcmp(&boot_part
->sub
.gpt
.part_guid
, gpt_guid
, sizeof(*gpt_guid
)))
125 *_boot_part
= boot_part
;
130 * Search for a specific drive/partition, based on the GPT label.
131 * Return drive and iterator at proper position.
133 static int find_by_label(const char *label
, struct part_iter
**_boot_part
)
135 struct part_iter
*boot_part
= NULL
;
136 struct disk_info diskinfo
;
139 for (drive
= 0x80; drive
< 0x80 + fixed_cnt
; drive
++) {
140 if (disk_get_params(drive
, &diskinfo
))
141 continue; /* Drive doesn't exist */
142 if (!(boot_part
= pi_begin(&diskinfo
, 0)))
144 /* Check for a GPT disk */
145 if (!(boot_part
->type
== typegpt
)) {
149 /* Check for a matching partition */
150 while (!pi_next(&boot_part
)) {
151 if (!strcmp(label
, boot_part
->sub
.gpt
.part_label
))
157 *_boot_part
= boot_part
;
161 static void do_boot(struct data_area
*data
, int ndata
)
163 uint16_t *const bios_fbm
= (uint16_t *) 0x413;
164 addr_t dosmem
= (addr_t
)(*bios_fbm
<< 10); /* Technically a low bound */
165 struct syslinux_memmap
*mmap
;
166 struct syslinux_movelist
*mlist
= NULL
;
168 uint8_t driveno
= opt
.regs
.edx
.b
[0];
169 uint8_t swapdrive
= driveno
& 0x80;
172 mmap
= syslinux_memory_map();
175 error("Cannot read system memory map\n");
180 for (i
= 0; i
< ndata
; i
++) {
181 if (data
[i
].base
+ data
[i
].size
> endimage
)
182 endimage
= data
[i
].base
+ data
[i
].size
;
184 if (endimage
> dosmem
)
187 for (i
= 0; i
< ndata
; i
++) {
188 if (syslinux_add_movelist(&mlist
, data
[i
].base
,
189 (addr_t
) data
[i
].data
, data
[i
].size
))
193 if (opt
.swap
&& driveno
!= swapdrive
) {
194 static const uint8_t swapstub_master
[] = {
195 /* The actual swap code */
196 0x53, /* 00: push bx */
197 0x0f, 0xb6, 0xda, /* 01: movzx bx,dl */
198 0x2e, 0x8a, 0x57, 0x60, /* 04: mov dl,[cs:bx+0x60] */
199 0x5b, /* 08: pop bx */
200 0xea, 0, 0, 0, 0, /* 09: jmp far 0:0 */
201 0x90, 0x90, /* 0E: nop; nop */
202 /* Code to install this in the right location */
203 /* Entry with DS = CS; ES = SI = 0; CX = 256 */
204 0x26, 0x66, 0x8b, 0x7c, 0x4c, /* 10: mov edi,[es:si+4*0x13] */
205 0x66, 0x89, 0x3e, 0x0a, 0x00, /* 15: mov [0x0A],edi */
206 0x26, 0x8b, 0x3e, 0x13, 0x04, /* 1A: mov di,[es:0x413] */
207 0x4f, /* 1F: dec di */
208 0x26, 0x89, 0x3e, 0x13, 0x04, /* 20: mov [es:0x413],di */
209 0x66, 0xc1, 0xe7, 0x16, /* 25: shl edi,16+6 */
210 0x26, 0x66, 0x89, 0x7c, 0x4c, /* 29: mov [es:si+4*0x13],edi */
211 0x66, 0xc1, 0xef, 0x10, /* 2E: shr edi,16 */
212 0x8e, 0xc7, /* 32: mov es,di */
213 0x31, 0xff, /* 34: xor di,di */
214 0xf3, 0x66, 0xa5, /* 36: rep movsd */
215 0xbe, 0, 0, /* 39: mov si,0 */
216 0xbf, 0, 0, /* 3C: mov di,0 */
217 0x8e, 0xde, /* 3F: mov ds,si */
218 0x8e, 0xc7, /* 41: mov es,di */
219 0x66, 0xb9, 0, 0, 0, 0, /* 43: mov ecx,0 */
220 0x66, 0xbe, 0, 0, 0, 0, /* 49: mov esi,0 */
221 0x66, 0xbf, 0, 0, 0, 0, /* 4F: mov edi,0 */
222 0xea, 0, 0, 0, 0, /* 55: jmp 0:0 */
223 /* pad out to segment boundary */
224 0x90, 0x90, /* 5A: ... */
225 0x90, 0x90, 0x90, 0x90, /* 5C: ... */
227 static uint8_t swapstub
[1024];
230 /* Note: we can't rely on either INT 13h nor the dosmem
231 vector to be correct at this stage, so we have to use an
232 installer stub to put things in the right place.
233 Round the installer location to a 1K boundary so the only
234 possible overlap is the identity mapping. */
235 endimage
= (endimage
+ 1023u) & ~1023u;
237 /* Create swap stub */
238 memcpy(swapstub
, swapstub_master
, sizeof swapstub_master
);
239 *(uint16_t *) & swapstub
[0x3a] = opt
.regs
.ds
;
240 *(uint16_t *) & swapstub
[0x3d] = opt
.regs
.es
;
241 *(uint32_t *) & swapstub
[0x45] = opt
.regs
.ecx
.l
;
242 *(uint32_t *) & swapstub
[0x4b] = opt
.regs
.esi
.l
;
243 *(uint32_t *) & swapstub
[0x51] = opt
.regs
.edi
.l
;
244 *(uint16_t *) & swapstub
[0x56] = opt
.regs
.ip
;
245 *(uint16_t *) & swapstub
[0x58] = opt
.regs
.cs
;
246 p
= &swapstub
[sizeof swapstub_master
];
248 /* Mapping table; start out with identity mapping everything */
249 for (i
= 0; i
< 256; i
++)
252 /* And the actual swap */
253 p
[driveno
] = swapdrive
;
254 p
[swapdrive
] = driveno
;
256 /* Adjust registers */
257 opt
.regs
.ds
= opt
.regs
.cs
= (uint16_t)(endimage
>> 4);
258 opt
.regs
.esi
.l
= opt
.regs
.es
= 0;
259 opt
.regs
.ecx
.l
= sizeof swapstub
>> 2;
260 opt
.regs
.ip
= 0x10; /* Installer offset */
261 opt
.regs
.ebx
.b
[0] = opt
.regs
.edx
.b
[0] = swapdrive
;
263 if (syslinux_add_movelist(&mlist
, endimage
, (addr_t
) swapstub
,
267 endimage
+= sizeof swapstub
;
270 /* Tell the shuffler not to muck with this area... */
271 syslinux_add_memmap(&mmap
, endimage
, 0xa0000 - endimage
, SMT_RESERVED
);
273 /* Force text mode */
274 syslinux_force_text_mode();
276 fputs("Booting...\n", stdout
);
277 syslinux_shuffle_boot_rm(mlist
, mmap
, opt
.keeppxe
, &opt
.regs
);
278 error("Chainboot failed!\n");
282 error("Loader file too large\n");
286 error("Out of memory\n");
290 int find_dp(struct part_iter
**_iter
)
292 struct part_iter
*iter
= NULL
;
293 struct disk_info diskinfo
;
294 struct guid gpt_guid
;
296 int drive
, hd
, partition
;
297 const union syslinux_derivative_info
*sdi
;
299 sdi
= syslinux_derivative_info();
301 if (!strncmp(opt
.drivename
, "mbr", 3)) {
302 if (find_by_sig(strtoul(opt
.drivename
+ 4, NULL
, 0), &iter
) < 0) {
303 error("Unable to find requested MBR signature.\n");
306 } else if (!strncmp(opt
.drivename
, "guid", 4)) {
307 if (str_to_guid(opt
.drivename
+ 5, &gpt_guid
))
309 if (find_by_guid(&gpt_guid
, &iter
) < 0) {
310 error("Unable to find requested GPT disk or partition by guid.\n");
313 } else if (!strncmp(opt
.drivename
, "label", 5)) {
314 if (!opt
.drivename
[6]) {
315 error("No label specified.\n");
318 if (find_by_label(opt
.drivename
+ 6, &iter
) < 0) {
319 error("Unable to find requested GPT partition by label.\n");
322 } else if ((opt
.drivename
[0] == 'h' || opt
.drivename
[0] == 'f') &&
323 opt
.drivename
[1] == 'd') {
324 hd
= opt
.drivename
[0] == 'h' ? 0x80 : 0;
326 drive
= hd
| strtol(opt
.drivename
, NULL
, 0);
328 if (disk_get_params(drive
, &diskinfo
))
330 /* this will start iteration over FDD, possibly raw */
331 if (!(iter
= pi_begin(&diskinfo
, 0)))
334 } else if (!strcmp(opt
.drivename
, "boot") || !strcmp(opt
.drivename
, "fs")) {
335 if (!is_phys(sdi
->c
.filesystem
)) {
336 error("When syslinux is not booted from physical disk (or its emulation),\n"
337 "'boot' and 'fs' are meaningless.\n");
340 /* offsets match, but in case it changes in the future */
341 if (sdi
->c
.filesystem
== SYSLINUX_FS_ISOLINUX
) {
342 drive
= sdi
->iso
.drive_number
;
343 fs_lba
= *sdi
->iso
.partoffset
;
345 drive
= sdi
->disk
.drive_number
;
346 fs_lba
= *sdi
->disk
.partoffset
;
348 if (disk_get_params(drive
, &diskinfo
))
350 /* this will start iteration over disk emulation, possibly raw */
351 if (!(iter
= pi_begin(&diskinfo
, 0)))
354 /* 'fs' => we should lookup the syslinux partition number and use it */
355 if (!strcmp(opt
.drivename
, "fs")) {
356 while (!pi_next(&iter
)) {
357 if (iter
->start_lba
== fs_lba
)
360 /* broken part structure or other problems */
362 error("Can't find myself on the drive I booted from.\n");
367 error("Unparsable drive specification.\n");
370 /* main options done - only thing left is explicit partition specification,
371 * if we're still at the disk stage with the iterator AND user supplied
372 * partition number (including disk pseudo-partition).
374 if (!iter
->index
&& opt
.partition
) {
375 partition
= strtol(opt
.partition
, NULL
, 0);
376 /* search for matching part#, including disk */
378 if (iter
->index
== partition
)
380 } while (!pi_next(&iter
));
382 error("Requested disk / partition combination not found.\n");
387 if (!(iter
->di
.disk
& 0x80) && iter
->index
) {
388 error("WARNING: Partitions on floppy devices may not work.\n");
400 static int setup_handover(const struct part_iter
*iter
,
401 struct data_area
*data
)
403 struct disk_dos_part_entry
*ha
;
407 if (!iter
->index
) { /* implies typeraw or non-iterated */
409 /* RAW handover protocol */
410 synth_size
= sizeof(struct disk_dos_part_entry
);
411 ha
= malloc(synth_size
);
413 error("Could not build RAW hand-over record!\n");
417 if (iter
->length
< len
)
418 len
= (uint32_t)iter
->length
;
419 lba2chs(&ha
->start
, &iter
->di
, 0, l2c_cadd
);
420 lba2chs(&ha
->end
, &iter
->di
, len
- 1, l2c_cadd
);
421 ha
->active_flag
= 0x80;
422 ha
->ostype
= 0xDA; /* "Non-FS Data", anything is good here though ... */
425 } else if (iter
->type
== typegpt
) {
426 /* GPT handover protocol */
427 synth_size
= sizeof(struct disk_dos_part_entry
) +
428 sizeof(uint32_t) + (uint32_t)iter
->sub
.gpt
.pe_size
;
429 ha
= malloc(synth_size
);
431 error("Could not build GPT hand-over record!\n");
434 lba2chs(&ha
->start
, &iter
->di
, iter
->start_lba
, l2c_cadd
);
435 lba2chs(&ha
->end
, &iter
->di
, iter
->start_lba
+ iter
->length
- 1, l2c_cadd
);
436 ha
->active_flag
= 0x80;
438 /* All bits set by default */
441 /* If these fit the precision, pass them on */
442 if (iter
->start_lba
< ha
->start_lba
)
443 ha
->start_lba
= (uint32_t)iter
->start_lba
;
444 if (iter
->length
< ha
->length
)
445 ha
->length
= (uint32_t)iter
->length
;
446 /* Next comes the GPT partition record length */
447 plen
= (uint32_t *) (ha
+ 1);
448 plen
[0] = (uint32_t)iter
->sub
.gpt
.pe_size
;
449 /* Next comes the GPT partition record copy */
450 memcpy(plen
+ 1, iter
->record
, plen
[0]);
452 dprintf("GPT handover:\n");
453 disk_dos_part_dump(ha
);
454 disk_gpt_part_dump((struct disk_gpt_part_entry
*)(plen
+ 1));
456 } else if (iter
->type
== typedos
) {
457 /* MBR handover protocol */
458 synth_size
= sizeof(struct disk_dos_part_entry
);
459 ha
= malloc(synth_size
);
461 error("Could not build MBR hand-over record!\n");
464 memcpy(ha
, iter
->record
, synth_size
);
465 /* make sure these match bios imaginations and are ebr agnostic */
466 lba2chs(&ha
->start
, &iter
->di
, iter
->start_lba
, l2c_cadd
);
467 lba2chs(&ha
->end
, &iter
->di
, iter
->start_lba
+ iter
->length
- 1, l2c_cadd
);
468 ha
->start_lba
= (uint32_t)iter
->start_lba
;
469 ha
->length
= (uint32_t)iter
->length
;
472 dprintf("MBR handover:\n");
473 disk_dos_part_dump(ha
);
475 /* shouldn't ever happen */
481 data
->size
= synth_size
;
482 data
->data
= (void *)ha
;
489 int main(int argc
, char *argv
[])
491 struct part_iter
*iter
= NULL
;
493 struct data_area fdat
, hdat
, sdat
, data
[3];
498 memset(&fdat
, 0, sizeof(fdat
));
499 memset(&hdat
, 0, sizeof(hdat
));
500 memset(&sdat
, 0, sizeof(sdat
));
503 if (opt_parse_args(argc
, argv
))
507 /* Get max fixed disk number */
508 fixed_cnt
= *(uint8_t *)(0x475);
511 * hmm, looks like we can't do that -
512 * some bioses/vms just set it to 1
513 * and go on living happily
514 * any better options than hardcoded 0x80 - 0xFF ?
518 /* Get disk/part iterator matching user supplied options */
522 /* Perform initial partition entry mangling */
523 if (manglepe_fixchs(iter
))
525 if (manglepe_hide(iter
))
528 /* Load the boot file */
530 fdat
.base
= (opt
.fseg
<< 4) + opt
.foff
;
532 if (loadfile(opt
.file
, &fdat
.data
, &fdat
.size
)) {
533 error("Couldn't read the boot file.\n");
536 if (fdat
.base
+ fdat
.size
- 1 > ADDRMAX
) {
537 error("The boot file is too big to load at this address.\n");
542 /* Load the sector */
544 sdat
.base
= (opt
.sseg
<< 4) + opt
.soff
;
545 sdat
.size
= iter
->di
.bps
;
547 if (sdat
.base
+ sdat
.size
- 1 > ADDRMAX
) {
548 error("The sector cannot be loaded at such high address.\n");
551 if (!(sdat
.data
= disk_read_sectors(&iter
->di
, iter
->start_lba
, 1))) {
552 error("Couldn't read the sector.\n");
556 if (!(sbck
= malloc(sdat
.size
))) {
557 error("Couldn't allocate cmp-buf for option 'save'.\n");
560 memcpy(sbck
, sdat
.data
, sdat
.size
);
562 if (opt
.file
&& opt
.maps
&& overlap(&fdat
, &sdat
)) {
563 error("WARNING: The sector won't be mmapped, as it would conflict with the boot file.\n");
568 /* Prep the handover */
570 if (setup_handover(iter
, &hdat
))
572 /* Verify possible conflicts */
573 if ( ( opt
.file
&& overlap(&fdat
, &hdat
)) ||
574 ( opt
.maps
&& overlap(&sdat
, &hdat
)) ) {
575 error("WARNING: Handover area won't be prepared,\n"
576 "as it would conflict with the boot file and/or the sector.\n");
581 /* Adjust registers */
584 mangler_handover(iter
, &hdat
);
587 /* Patching functions */
589 if (manglef_isolinux(&fdat
))
592 if (manglef_grub(iter
, &fdat
))
595 if (manglef_drmk(&fdat
))
598 if (manglef_bpb(iter
, &fdat
))
601 if (mangles_bpb(iter
, &sdat
))
604 if (mangles_save(iter
, &sdat
, sbck
))
607 if (manglesf_bss(&sdat
, &fdat
))
610 /* This *must* be after BPB saving or copying */
611 if (mangles_cmldr(&sdat
))
615 * Prepare boot-time mmap data. We should to it here, as manglers could
616 * potentially alter some of the data.
620 memcpy(data
+ ndata
++, &fdat
, sizeof(fdat
));
622 memcpy(data
+ ndata
++, &sdat
, sizeof(sdat
));
624 memcpy(data
+ ndata
++, &hdat
, sizeof(hdat
));
627 printf("iter->di dsk, bps: %X, %u\niter->di lbacnt, C*H*S: %llu, %u\n"
628 "iter->di C, H, S: %u, %u, %u\n",
629 iter
->di
.disk
, iter
->di
.bps
,
630 iter
->di
.lbacnt
, iter
->di
.cyl
* iter
->di
.head
* iter
->di
.spt
,
631 iter
->di
.cyl
, iter
->di
.head
, iter
->di
.spt
);
632 printf("iter idx: %d\n", iter
->index
);
633 printf("iter lba: %llu\n", iter
->start_lba
);
635 printf("hand lba: %u\n",
636 ((struct disk_dos_part_entry
*)hdat
.data
)->start_lba
);
640 puts("Press any key to continue booting...");
644 if (ndata
&& opt
.chain
) /* boot only if we actually chainload */
645 do_boot(data
, ndata
);
647 error("Service-only run completed, exiting.\n");
650 /* Free allocated areas */
658 /* vim: set ts=8 sts=4 sw=4 noet: */