1 /*
2 * QEMU S390 bootmap interpreter
3 *
4 * Copyright (c) 2009 Alexander Graf <agraf@suse.de>
5 *
6 * This work is licensed under the terms of the GNU GPL, version 2 or (at
7 * your option) any later version. See the COPYING file in the top-level
8 * directory.
9 */
10
11 #include <string.h>
12 #include <stdio.h>
13 #include "s390-ccw.h"
14 #include "s390-arch.h"
15 #include "bootmap.h"
16 #include "virtio.h"
17 #include "bswap.h"
18
19 #ifdef DEBUG
20 /* #define DEBUG_FALLBACK */
21 #endif
22
23 #ifdef DEBUG_FALLBACK
24 #define dputs(txt) \
25 do { printf("zipl: " txt); } while (0)
26 #else
27 #define dputs(fmt, ...) \
28 do { } while (0)
29 #endif
30
31 /* Scratch space */
32 static uint8_t sec[MAX_SECTOR_SIZE*4] __attribute__((__aligned__(PAGE_SIZE)));
33
34 const uint8_t el_torito_magic[] = "EL TORITO SPECIFICATION"
35 "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";
36
37 /*
38 * Match two CCWs located after PSW and eight filler bytes.
39 * From libmagic and arch/s390/kernel/head.S.
40 */
41 const uint8_t linux_s390_magic[] = "\x02\x00\x00\x18\x60\x00\x00\x50\x02\x00"
42 "\x00\x68\x60\x00\x00\x50\x40\x40\x40\x40"
43 "\x40\x40\x40\x40";
44
is_iso_vd_valid(IsoVolDesc * vd)45 static inline bool is_iso_vd_valid(IsoVolDesc *vd)
46 {
47 const uint8_t vol_desc_magic[] = "CD001";
48
49 return !memcmp(&vd->ident[0], vol_desc_magic, 5) &&
50 vd->version == 0x1 &&
51 vd->type <= VOL_DESC_TYPE_PARTITION;
52 }
53
54 /***********************************************************************
55 * IPL an ECKD DASD (CDL or LDL/CMS format)
56 */
57
58 static unsigned char _bprs[8*1024]; /* guessed "max" ECKD sector size */
59 static const int max_bprs_entries = sizeof(_bprs) / sizeof(ExtEckdBlockPtr);
60 static uint8_t _s2[MAX_SECTOR_SIZE * 3] __attribute__((__aligned__(PAGE_SIZE)));
61 static void *s2_prev_blk = _s2;
62 static void *s2_cur_blk = _s2 + MAX_SECTOR_SIZE;
63 static void *s2_next_blk = _s2 + MAX_SECTOR_SIZE * 2;
64
verify_boot_info(BootInfo * bip)65 static inline int verify_boot_info(BootInfo *bip)
66 {
67 if (!magic_match(bip->magic, ZIPL_MAGIC)) {
68 puts("No zIPL sig in BootInfo");
69 return -EINVAL;
70 }
71 if (bip->version != BOOT_INFO_VERSION) {
72 puts("Wrong zIPL version");
73 return -EINVAL;
74 }
75 if (bip->bp_type != BOOT_INFO_BP_TYPE_IPL) {
76 puts("DASD is not for IPL");
77 return -ENODEV;
78 }
79 if (bip->dev_type != BOOT_INFO_DEV_TYPE_ECKD) {
80 puts("DASD is not ECKD");
81 return -ENODEV;
82 }
83 if (bip->flags != BOOT_INFO_FLAGS_ARCH) {
84 puts("Not for this arch");
85 return -EINVAL;
86 }
87 if (!block_size_ok(bip->bp.ipl.bm_ptr.eckd.bptr.size)) {
88 puts("Bad block size in zIPL section of 1st record");
89 return -EINVAL;
90 }
91
92 return 0;
93 }
94
eckd_format_chs(ExtEckdBlockPtr * ptr,bool ldipl,uint64_t * c,uint64_t * h,uint64_t * s)95 static void eckd_format_chs(ExtEckdBlockPtr *ptr, bool ldipl,
96 uint64_t *c,
97 uint64_t *h,
98 uint64_t *s)
99 {
100 if (ldipl) {
101 *c = ptr->ldptr.chs.cylinder;
102 *h = ptr->ldptr.chs.head;
103 *s = ptr->ldptr.chs.sector;
104 } else {
105 *c = ptr->bptr.chs.cylinder;
106 *h = ptr->bptr.chs.head;
107 *s = ptr->bptr.chs.sector;
108 }
109 }
110
eckd_chs_to_block(uint64_t c,uint64_t h,uint64_t s)111 static block_number_t eckd_chs_to_block(uint64_t c, uint64_t h, uint64_t s)
112 {
113 const uint64_t sectors = virtio_get_sectors();
114 const uint64_t heads = virtio_get_heads();
115 const uint64_t cylinder = c + ((h & 0xfff0) << 12);
116 const uint64_t head = h & 0x000f;
117 const block_number_t block = sectors * heads * cylinder
118 + sectors * head
119 + s - 1; /* block nr starts with zero */
120 return block;
121 }
122
eckd_block_num(EckdCHS * chs)123 static block_number_t eckd_block_num(EckdCHS *chs)
124 {
125 return eckd_chs_to_block(chs->cylinder, chs->head, chs->sector);
126 }
127
gen_eckd_block_num(ExtEckdBlockPtr * ptr,bool ldipl)128 static block_number_t gen_eckd_block_num(ExtEckdBlockPtr *ptr, bool ldipl)
129 {
130 uint64_t cyl, head, sec;
131 eckd_format_chs(ptr, ldipl, &cyl, &head, &sec);
132 return eckd_chs_to_block(cyl, head, sec);
133 }
134
eckd_valid_chs(uint64_t cyl,uint64_t head,uint64_t sector)135 static bool eckd_valid_chs(uint64_t cyl, uint64_t head, uint64_t sector)
136 {
137 if (head >= virtio_get_heads()
138 || sector > virtio_get_sectors()
139 || sector <= 0) {
140 return false;
141 }
142
143 if (!virtio_guessed_disk_nature() &&
144 eckd_chs_to_block(cyl, head, sector) >= virtio_get_blocks()) {
145 return false;
146 }
147
148 return true;
149 }
150
eckd_valid_address(ExtEckdBlockPtr * ptr,bool ldipl)151 static bool eckd_valid_address(ExtEckdBlockPtr *ptr, bool ldipl)
152 {
153 uint64_t cyl, head, sec;
154 eckd_format_chs(ptr, ldipl, &cyl, &head, &sec);
155 return eckd_valid_chs(cyl, head, sec);
156 }
157
load_eckd_segments(block_number_t blk,bool ldipl,uint64_t * address)158 static block_number_t load_eckd_segments(block_number_t blk, bool ldipl,
159 uint64_t *address)
160 {
161 block_number_t block_nr;
162 int j, rc, count;
163 BootMapPointer *bprs = (void *)_bprs;
164 bool more_data;
165
166 memset(_bprs, FREE_SPACE_FILLER, sizeof(_bprs));
167 if (virtio_read(blk, bprs)) {
168 puts("BPRS read failed");
169 return ERROR_BLOCK_NR;
170 }
171
172 do {
173 more_data = false;
174 for (j = 0;; j++) {
175 block_nr = gen_eckd_block_num(&bprs[j].xeckd, ldipl);
176 if (is_null_block_number(block_nr)) { /* end of chunk */
177 return NULL_BLOCK_NR;
178 }
179
180 /* we need the updated blockno for the next indirect entry
181 * in the chain, but don't want to advance address
182 */
183 if (j == (max_bprs_entries - 1)) {
184 break;
185 }
186
187 /* List directed pointer does not store block size */
188 if (!ldipl && !block_size_ok(bprs[j].xeckd.bptr.size)) {
189 puts("Bad chunk block size");
190 return ERROR_BLOCK_NR;
191 }
192
193 if (!eckd_valid_address(&bprs[j].xeckd, ldipl)) {
194 /*
195 * If an invalid address is found during LD-IPL then break and
196 * retry as CCW-IPL, otherwise abort on error
197 */
198 if (!ldipl) {
199 puts("Bad chunk ECKD address");
200 return ERROR_BLOCK_NR;
201 }
202 break;
203 }
204
205 if (ldipl) {
206 count = bprs[j].xeckd.ldptr.count;
207 } else {
208 count = bprs[j].xeckd.bptr.count;
209 }
210
211 if (count == 0 && unused_space(&bprs[j + 1],
212 sizeof(EckdBlockPtr))) {
213 /* This is a "continue" pointer.
214 * This ptr should be the last one in the current
215 * script section.
216 * I.e. the next ptr must point to the unused memory area
217 */
218 memset(_bprs, FREE_SPACE_FILLER, sizeof(_bprs));
219 if (virtio_read(block_nr, bprs)) {
220 puts("BPRS continuation read failed");
221 return ERROR_BLOCK_NR;
222 }
223 more_data = true;
224 break;
225 }
226
227 /* Load (count+1) blocks of code at (block_nr)
228 * to memory (address).
229 */
230 rc = virtio_read_many(block_nr, (void *)(*address), count + 1);
231 if (rc != 0) {
232 puts("Code chunk read failed");
233 return ERROR_BLOCK_NR;
234 }
235
236 *address += (count + 1) * virtio_get_block_size();
237 }
238 } while (more_data);
239 return block_nr;
240 }
241
find_zipl_boot_menu_banner(int * offset)242 static bool find_zipl_boot_menu_banner(int *offset)
243 {
244 int i;
245
246 /* Menu banner starts with "zIPL" */
247 for (i = 0; i <= virtio_get_block_size() - 4; i++) {
248 if (magic_match(s2_cur_blk + i, ZIPL_MAGIC_EBCDIC)) {
249 *offset = i;
250 return true;
251 }
252 }
253
254 return false;
255 }
256
eckd_get_boot_menu_index(block_number_t s1b_block_nr)257 static int eckd_get_boot_menu_index(block_number_t s1b_block_nr)
258 {
259 block_number_t cur_block_nr;
260 block_number_t prev_block_nr = 0;
261 block_number_t next_block_nr = 0;
262 EckdStage1b *s1b = (void *)sec;
263 int banner_offset;
264 int i;
265
266 /* Get Stage1b data */
267 memset(sec, FREE_SPACE_FILLER, sizeof(sec));
268 if (virtio_read(s1b_block_nr, s1b)) {
269 puts("Cannot read stage1b boot loader");
270 return -EIO;
271 }
272
273 memset(_s2, FREE_SPACE_FILLER, sizeof(_s2));
274
275 /* Get Stage2 data */
276 for (i = 0; i < STAGE2_BLK_CNT_MAX; i++) {
277 cur_block_nr = eckd_block_num(&s1b->seek[i].chs);
278
279 if (!cur_block_nr || is_null_block_number(cur_block_nr)) {
280 break;
281 }
282
283 if (virtio_read(cur_block_nr, s2_cur_blk)) {
284 puts("Cannot read stage2 boot loader");
285 return -EIO;
286 }
287
288 if (find_zipl_boot_menu_banner(&banner_offset)) {
289 /*
290 * Load the adjacent blocks to account for the
291 * possibility of menu data spanning multiple blocks.
292 */
293 if (prev_block_nr) {
294 if (virtio_read(prev_block_nr, s2_prev_blk)) {
295 puts("Cannot read stage2 boot loader");
296 return -EIO;
297 }
298 }
299
300 if (i + 1 < STAGE2_BLK_CNT_MAX) {
301 next_block_nr = eckd_block_num(&s1b->seek[i + 1].chs);
302 }
303
304 if (next_block_nr && !is_null_block_number(next_block_nr)) {
305 if (virtio_read(next_block_nr, s2_next_blk)) {
306 puts("Cannot read stage2 boot loader");
307 return -EIO;
308 }
309 }
310
311 return menu_get_zipl_boot_index(s2_cur_blk + banner_offset);
312 }
313
314 prev_block_nr = cur_block_nr;
315 }
316
317 printf("No zipl boot menu data found. Booting default entry.");
318 return 0;
319 }
320
run_eckd_boot_script(block_number_t bmt_block_nr,block_number_t s1b_block_nr)321 static int run_eckd_boot_script(block_number_t bmt_block_nr,
322 block_number_t s1b_block_nr)
323 {
324 int i;
325 unsigned int loadparm = get_loadparm_index();
326 block_number_t block_nr;
327 uint64_t address;
328 BootMapTable *bmt = (void *)sec;
329 BootMapScript *bms = (void *)sec;
330 /* The S1B block number is NULL_BLOCK_NR if and only if it's an LD-IPL */
331 bool ldipl = (s1b_block_nr == NULL_BLOCK_NR);
332
333 if (menu_is_enabled_zipl() && !ldipl) {
334 loadparm = eckd_get_boot_menu_index(s1b_block_nr);
335 }
336
337 debug_print_int("loadparm", loadparm);
338 if (loadparm >= MAX_BOOT_ENTRIES) {
339 panic("loadparm value greater than max number of boot entries allowed");
340 }
341
342 memset(sec, FREE_SPACE_FILLER, sizeof(sec));
343 if (virtio_read(bmt_block_nr, sec)) {
344 puts("Cannot read Boot Map Table");
345 return -EIO;
346 }
347
348 block_nr = gen_eckd_block_num(&bmt->entry[loadparm].xeckd, ldipl);
349 if (block_nr == NULL_BLOCK_NR) {
350 printf("The requested boot entry (%d) is invalid\n", loadparm);
351 panic("Invalid loadparm");
352 }
353
354 memset(sec, FREE_SPACE_FILLER, sizeof(sec));
355 if (virtio_read(block_nr, sec)) {
356 puts("Cannot read Boot Map Script");
357 return -EIO;
358 }
359
360 for (i = 0; bms->entry[i].type == BOOT_SCRIPT_LOAD ||
361 bms->entry[i].type == BOOT_SCRIPT_SIGNATURE; i++) {
362
363 /* We don't support secure boot yet, so we skip signature entries */
364 if (bms->entry[i].type == BOOT_SCRIPT_SIGNATURE) {
365 continue;
366 }
367
368 address = bms->entry[i].address.load_address;
369 block_nr = gen_eckd_block_num(&bms->entry[i].blkptr.xeckd, ldipl);
370
371 do {
372 block_nr = load_eckd_segments(block_nr, ldipl, &address);
373 if (block_nr == ERROR_BLOCK_NR) {
374 return ldipl ? 0 : -EIO;
375 }
376 } while (block_nr != NULL_BLOCK_NR);
377 }
378
379 if (ldipl && bms->entry[i].type != BOOT_SCRIPT_EXEC) {
380 /* Abort LD-IPL and retry as CCW-IPL */
381 return 0;
382 }
383
384 if (bms->entry[i].type != BOOT_SCRIPT_EXEC) {
385 puts("Unknown script entry type");
386 return -EINVAL;
387 }
388 write_reset_psw(bms->entry[i].address.load_address);
389 jump_to_IPL_code(0);
390 return -1;
391 }
392
ipl_eckd_cdl(void)393 static int ipl_eckd_cdl(void)
394 {
395 XEckdMbr *mbr;
396 EckdCdlIpl2 *ipl2 = (void *)sec;
397 IplVolumeLabel *vlbl = (void *)sec;
398 block_number_t bmt_block_nr, s1b_block_nr;
399
400 /* we have just read the block #0 and recognized it as "IPL1" */
401 puts("CDL");
402
403 memset(sec, FREE_SPACE_FILLER, sizeof(sec));
404 if (virtio_read(1, ipl2)) {
405 puts("Cannot read IPL2 record at block 1");
406 return -EIO;
407 }
408
409 mbr = &ipl2->mbr;
410 if (!magic_match(mbr, ZIPL_MAGIC)) {
411 puts("No zIPL section in IPL2 record.");
412 return 0;
413 }
414 if (!block_size_ok(mbr->blockptr.xeckd.bptr.size)) {
415 puts("Bad block size in zIPL section of IPL2 record.");
416 return 0;
417 }
418 if (mbr->dev_type != DEV_TYPE_ECKD) {
419 puts("Non-ECKD device type in zIPL section of IPL2 record.");
420 return 0;
421 }
422
423 /* save pointer to Boot Map Table */
424 bmt_block_nr = eckd_block_num(&mbr->blockptr.xeckd.bptr.chs);
425
426 /* save pointer to Stage1b Data */
427 s1b_block_nr = eckd_block_num(&ipl2->stage1.seek[0].chs);
428
429 memset(sec, FREE_SPACE_FILLER, sizeof(sec));
430 if (virtio_read(2, vlbl)) {
431 puts("Cannot read Volume Label at block 2");
432 return -EIO;
433 }
434 if (!magic_match(vlbl->key, VOL1_MAGIC)) {
435 puts("Invalid magic of volume label block.");
436 return 0;
437 }
438 if (!magic_match(vlbl->f.key, VOL1_MAGIC)) {
439 puts("Invalid magic of volser block.");
440 return 0;
441 }
442 print_volser(vlbl->f.volser);
443
444 return run_eckd_boot_script(bmt_block_nr, s1b_block_nr);
445 }
446
print_eckd_ldl_msg(ECKD_IPL_mode_t mode)447 static void print_eckd_ldl_msg(ECKD_IPL_mode_t mode)
448 {
449 LDL_VTOC *vlbl = (void *)sec; /* already read, 3rd block */
450 char msg[4] = { '?', '.', '\n', '\0' };
451
452 printf((mode == ECKD_CMS) ? "CMS" : "LDL");
453 printf(" version ");
454 switch (vlbl->LDL_version) {
455 case LDL1_VERSION:
456 msg[0] = '1';
457 break;
458 case LDL2_VERSION:
459 msg[0] = '2';
460 break;
461 default:
462 msg[0] = ebc2asc[vlbl->LDL_version];
463 msg[1] = '?';
464 break;
465 }
466 printf("%s", msg);
467 print_volser(vlbl->volser);
468 }
469
ipl_eckd_ldl(ECKD_IPL_mode_t mode)470 static int ipl_eckd_ldl(ECKD_IPL_mode_t mode)
471 {
472 block_number_t bmt_block_nr, s1b_block_nr;
473 EckdLdlIpl1 *ipl1 = (void *)sec;
474
475 if (mode != ECKD_LDL_UNLABELED) {
476 print_eckd_ldl_msg(mode);
477 }
478
479 /* DO NOT read BootMap pointer (only one, xECKD) at block #2 */
480
481 memset(sec, FREE_SPACE_FILLER, sizeof(sec));
482 if (virtio_read(0, sec)) {
483 puts("Cannot read block 0 to grab boot info.");
484 return -EIO;
485 }
486 if (mode == ECKD_LDL_UNLABELED) {
487 if (!magic_match(ipl1->bip.magic, ZIPL_MAGIC)) {
488 return 0; /* not applicable layout */
489 }
490 puts("unlabeled LDL.");
491 }
492 verify_boot_info(&ipl1->bip);
493
494 /* save pointer to Boot Map Table */
495 bmt_block_nr = eckd_block_num(&ipl1->bip.bp.ipl.bm_ptr.eckd.bptr.chs);
496
497 /* save pointer to Stage1b Data */
498 s1b_block_nr = eckd_block_num(&ipl1->stage1.seek[0].chs);
499
500 return run_eckd_boot_script(bmt_block_nr, s1b_block_nr);
501 }
502
eckd_find_bmt(ExtEckdBlockPtr * ptr)503 static block_number_t eckd_find_bmt(ExtEckdBlockPtr *ptr)
504 {
505 block_number_t blockno;
506 uint8_t tmp_sec[MAX_SECTOR_SIZE];
507 BootRecord *br;
508
509 blockno = gen_eckd_block_num(ptr, 0);
510 if (virtio_read(blockno, tmp_sec)) {
511 puts("Cannot read boot record");
512 return ERROR_BLOCK_NR;
513 }
514 br = (BootRecord *)tmp_sec;
515 if (!magic_match(br->magic, ZIPL_MAGIC)) {
516 /* If the boot record is invalid, return and try CCW-IPL instead */
517 return NULL_BLOCK_NR;
518 }
519
520 return gen_eckd_block_num(&br->pgt.xeckd, 1);
521 }
522
print_eckd_msg(void)523 static void print_eckd_msg(void)
524 {
525 char msg[] = "Using ECKD scheme (block size *****), ";
526 char *p = &msg[34], *q = &msg[30];
527 int n = virtio_get_block_size();
528
529 /* Fill in the block size and show up the message */
530 if (n > 0 && n <= 99999) {
531 while (n) {
532 *p-- = '0' + (n % 10);
533 n /= 10;
534 }
535 while (p >= q) {
536 *p-- = ' ';
537 }
538 }
539 printf("%s", msg);
540 }
541
ipl_eckd(void)542 static int ipl_eckd(void)
543 {
544 IplVolumeLabel *vlbl = (void *)sec;
545 LDL_VTOC *vtoc = (void *)sec;
546 block_number_t ldipl_bmt; /* Boot Map Table for List-Directed IPL */
547
548 print_eckd_msg();
549
550 /* Block 2 can contain either the CDL VOL1 label or the LDL VTOC */
551 memset(sec, FREE_SPACE_FILLER, sizeof(sec));
552 if (virtio_read(2, vlbl)) {
553 puts("Cannot read block 2");
554 return -EIO;
555 }
556
557 /*
558 * First check for a list-directed-format pointer which would
559 * supersede the CCW pointer.
560 */
561 if (eckd_valid_address((ExtEckdBlockPtr *)&vlbl->f.br, 0)) {
562 ldipl_bmt = eckd_find_bmt((ExtEckdBlockPtr *)&vlbl->f.br);
563 switch (ldipl_bmt) {
564 case ERROR_BLOCK_NR:
565 return -EIO;
566 case NULL_BLOCK_NR:
567 break; /* Invalid BMT but the device may still boot with CCW-IPL */
568 default:
569 puts("List-Directed");
570 /*
571 * LD-IPL does not use the S1B bock, just make it NULL_BLOCK_NR.
572 * In some failure cases retry IPL before aborting.
573 */
574 if (run_eckd_boot_script(ldipl_bmt, NULL_BLOCK_NR)) {
575 return -EIO;
576 }
577 /* Non-fatal error, retry as CCW-IPL */
578 printf("Retrying IPL ");
579 print_eckd_msg();
580 }
581 memset(sec, FREE_SPACE_FILLER, sizeof(sec));
582 if (virtio_read(2, vtoc)) {
583 puts("Cannot read block 2");
584 return -EIO;
585 }
586 }
587
588 /* Not list-directed */
589 if (magic_match(vtoc->magic, VOL1_MAGIC)) {
590 if (ipl_eckd_cdl()) {
591 return -1;
592 }
593 }
594
595 if (magic_match(vtoc->magic, CMS1_MAGIC)) {
596 return ipl_eckd_ldl(ECKD_CMS);
597 }
598 if (magic_match(vtoc->magic, LNX1_MAGIC)) {
599 return ipl_eckd_ldl(ECKD_LDL);
600 }
601
602 if (ipl_eckd_ldl(ECKD_LDL_UNLABELED)) {
603 return -1;
604 }
605 /*
606 * Ok, it is not a LDL by any means.
607 * It still might be a CDL with zero record keys for IPL1 and IPL2
608 */
609 return ipl_eckd_cdl();
610 }
611
612 /***********************************************************************
613 * IPL a SCSI disk
614 */
615
zipl_load_segment(ComponentEntry * entry)616 static int zipl_load_segment(ComponentEntry *entry)
617 {
618 const int max_entries = (MAX_SECTOR_SIZE / sizeof(ScsiBlockPtr));
619 ScsiBlockPtr *bprs = (void *)sec;
620 const int bprs_size = sizeof(sec);
621 block_number_t blockno;
622 uint64_t address;
623 int i;
624 char err_msg[] = "zIPL failed to read BPRS at 0xZZZZZZZZZZZZZZZZ";
625 char *blk_no = &err_msg[30]; /* where to print blockno in (those ZZs) */
626
627 blockno = entry->data.blockno;
628 address = entry->compdat.load_addr;
629
630 debug_print_int("loading segment at block", blockno);
631 debug_print_int("addr", address);
632
633 do {
634 memset(bprs, FREE_SPACE_FILLER, bprs_size);
635 fill_hex_val(blk_no, &blockno, sizeof(blockno));
636 if (virtio_read(blockno, bprs)) {
637 puts(err_msg);
638 return -EIO;
639 }
640
641 for (i = 0;; i++) {
642 uint64_t *cur_desc = (void *)&bprs[i];
643
644 blockno = bprs[i].blockno;
645 if (!blockno) {
646 break;
647 }
648
649 /* we need the updated blockno for the next indirect entry in the
650 chain, but don't want to advance address */
651 if (i == (max_entries - 1)) {
652 break;
653 }
654
655 if (bprs[i].blockct == 0 && unused_space(&bprs[i + 1],
656 sizeof(ScsiBlockPtr))) {
657 /* This is a "continue" pointer.
658 * This ptr is the last one in the current script section.
659 * I.e. the next ptr must point to the unused memory area.
660 * The blockno is not zero, so the upper loop must continue
661 * reading next section of BPRS.
662 */
663 break;
664 }
665 address = virtio_load_direct(cur_desc[0], cur_desc[1], 0,
666 (void *)address);
667 if (!address) {
668 puts("zIPL load segment failed");
669 return -EIO;
670 }
671 }
672 } while (blockno);
673
674 return 0;
675 }
676
677 /* Run a zipl program */
zipl_run(ScsiBlockPtr * pte)678 static int zipl_run(ScsiBlockPtr *pte)
679 {
680 ComponentHeader *header;
681 ComponentEntry *entry;
682 uint8_t tmp_sec[MAX_SECTOR_SIZE];
683
684 if (virtio_read(pte->blockno, tmp_sec)) {
685 puts("Cannot read header");
686 return -EIO;
687 }
688 header = (ComponentHeader *)tmp_sec;
689
690 if (!magic_match(tmp_sec, ZIPL_MAGIC)) {
691 puts("No zIPL magic in header");
692 return -EINVAL;
693 }
694 if (header->type != ZIPL_COMP_HEADER_IPL) {
695 puts("Bad header type");
696 return -EINVAL;
697 }
698
699 dputs("start loading images\n");
700
701 /* Load image(s) into RAM */
702 entry = (ComponentEntry *)(&header[1]);
703 while (entry->component_type == ZIPL_COMP_ENTRY_LOAD ||
704 entry->component_type == ZIPL_COMP_ENTRY_SIGNATURE) {
705
706 /* We don't support secure boot yet, so we skip signature entries */
707 if (entry->component_type == ZIPL_COMP_ENTRY_SIGNATURE) {
708 entry++;
709 continue;
710 }
711
712 if (zipl_load_segment(entry)) {
713 return -1;
714 }
715
716 entry++;
717
718 if ((uint8_t *)(&entry[1]) > (tmp_sec + MAX_SECTOR_SIZE)) {
719 puts("Wrong entry value");
720 return -EINVAL;
721 }
722 }
723
724 if (entry->component_type != ZIPL_COMP_ENTRY_EXEC) {
725 puts("No EXEC entry");
726 return -EINVAL;
727 }
728
729 /* should not return */
730 write_reset_psw(entry->compdat.load_psw);
731 jump_to_IPL_code(0);
732 return -1;
733 }
734
ipl_scsi(void)735 static int ipl_scsi(void)
736 {
737 ScsiMbr *mbr = (void *)sec;
738 int program_table_entries = 0;
739 BootMapTable *prog_table = (void *)sec;
740 unsigned int loadparm = get_loadparm_index();
741 bool valid_entries[MAX_BOOT_ENTRIES] = {false};
742 size_t i;
743
744 /* Grab the MBR */
745 memset(sec, FREE_SPACE_FILLER, sizeof(sec));
746 if (virtio_read(0, mbr)) {
747 puts("Cannot read block 0");
748 return -EIO;
749 }
750
751 if (!magic_match(mbr->magic, ZIPL_MAGIC)) {
752 return 0;
753 }
754
755 puts("Using SCSI scheme.");
756 debug_print_int("MBR Version", mbr->version_id);
757 IPL_check(mbr->version_id == 1,
758 "Unknown MBR layout version, assuming version 1");
759 debug_print_int("program table", mbr->pt.blockno);
760 if (!mbr->pt.blockno) {
761 puts("No Program Table");
762 return -EINVAL;
763 }
764
765 /* Parse the program table */
766 if (virtio_read(mbr->pt.blockno, sec)) {
767 puts("Error reading Program Table");
768 return -EIO;
769 }
770 if (!magic_match(sec, ZIPL_MAGIC)) {
771 puts("No zIPL magic in Program Table");
772 return -EINVAL;
773 }
774
775 for (i = 0; i < MAX_BOOT_ENTRIES; i++) {
776 if (prog_table->entry[i].scsi.blockno) {
777 valid_entries[i] = true;
778 program_table_entries++;
779 }
780 }
781
782 debug_print_int("program table entries", program_table_entries);
783 if (program_table_entries == 0) {
784 puts("Empty Program Table");
785 return -EINVAL;
786 }
787
788 if (menu_is_enabled_enum()) {
789 loadparm = menu_get_enum_boot_index(valid_entries);
790 }
791
792 debug_print_int("loadparm", loadparm);
793 if (loadparm >= MAX_BOOT_ENTRIES) {
794 panic("loadparm value greater than max number of boot entries allowed");
795 }
796
797 if (!valid_entries[loadparm]) {
798 printf("The requested boot entry (%d) is invalid\n", loadparm);
799 panic("Invalid loadparm");
800 }
801
802 return zipl_run(&prog_table->entry[loadparm].scsi);
803 }
804
805 /***********************************************************************
806 * IPL El Torito ISO9660 image or DVD
807 */
808
is_iso_bc_entry_compatible(IsoBcSection * s)809 static bool is_iso_bc_entry_compatible(IsoBcSection *s)
810 {
811 uint8_t *magic_sec = (uint8_t *)(sec + ISO_SECTOR_SIZE);
812
813 if (s->unused || !s->sector_count) {
814 return false;
815 }
816 if (virtio_read(bswap32(s->load_rba), magic_sec)) {
817 puts("Failed to read image sector 0");
818 return false;
819 }
820
821 /* Checking bytes 8 - 32 for S390 Linux magic */
822 return !memcmp(magic_sec + 8, linux_s390_magic, 24);
823 }
824
825 /* Location of the current sector of the directory */
826 static uint32_t sec_loc[ISO9660_MAX_DIR_DEPTH];
827 /* Offset in the current sector of the directory */
828 static uint32_t sec_offset[ISO9660_MAX_DIR_DEPTH];
829 /* Remained directory space in bytes */
830 static uint32_t dir_rem[ISO9660_MAX_DIR_DEPTH];
831
iso_get_file_size(uint32_t load_rba)832 static inline long iso_get_file_size(uint32_t load_rba)
833 {
834 IsoVolDesc *vd = (IsoVolDesc *)sec;
835 IsoDirHdr *cur_record = &vd->vd.primary.rootdir;
836 uint8_t *temp = sec + ISO_SECTOR_SIZE;
837 int level = 0;
838
839 if (virtio_read(ISO_PRIMARY_VD_SECTOR, sec)) {
840 puts("Failed to read ISO primary descriptor");
841 return -EIO;
842 }
843
844 sec_loc[0] = iso_733_to_u32(cur_record->ext_loc);
845 dir_rem[0] = 0;
846 sec_offset[0] = 0;
847
848 while (level >= 0) {
849 if (sec_offset[level] > ISO_SECTOR_SIZE) {
850 puts("Directory tree structure violation");
851 return -EIO;
852 }
853
854 cur_record = (IsoDirHdr *)(temp + sec_offset[level]);
855
856 if (sec_offset[level] == 0) {
857 if (virtio_read(sec_loc[level], temp)) {
858 puts("Failed to read ISO directory");
859 return -EIO;
860 }
861 if (dir_rem[level] == 0) {
862 /* Skip self and parent records */
863 dir_rem[level] = iso_733_to_u32(cur_record->data_len) -
864 cur_record->dr_len;
865 sec_offset[level] += cur_record->dr_len;
866
867 cur_record = (IsoDirHdr *)(temp + sec_offset[level]);
868 dir_rem[level] -= cur_record->dr_len;
869 sec_offset[level] += cur_record->dr_len;
870 continue;
871 }
872 }
873
874 if (!cur_record->dr_len || sec_offset[level] == ISO_SECTOR_SIZE) {
875 /* Zero-padding and/or the end of current sector */
876 dir_rem[level] -= ISO_SECTOR_SIZE - sec_offset[level];
877 sec_offset[level] = 0;
878 sec_loc[level]++;
879 } else {
880 /* The directory record is valid */
881 if (load_rba == iso_733_to_u32(cur_record->ext_loc)) {
882 return iso_733_to_u32(cur_record->data_len);
883 }
884
885 dir_rem[level] -= cur_record->dr_len;
886 sec_offset[level] += cur_record->dr_len;
887
888 if (cur_record->file_flags & 0x2) {
889 /* Subdirectory */
890 if (level == ISO9660_MAX_DIR_DEPTH - 1) {
891 puts("ISO-9660 directory depth limit exceeded");
892 } else {
893 level++;
894 sec_loc[level] = iso_733_to_u32(cur_record->ext_loc);
895 sec_offset[level] = 0;
896 dir_rem[level] = 0;
897 continue;
898 }
899 }
900 }
901
902 if (dir_rem[level] == 0) {
903 /* Nothing remaining */
904 level--;
905 if (virtio_read(sec_loc[level], temp)) {
906 puts("Failed to read ISO directory");
907 return -EIO;
908 }
909 }
910 }
911
912 return 0;
913 }
914
load_iso_bc_entry(IsoBcSection * load)915 static void load_iso_bc_entry(IsoBcSection *load)
916 {
917 IsoBcSection s = *load;
918 /*
919 * According to spec, extent for each file
920 * is padded and ISO_SECTOR_SIZE bytes aligned
921 */
922 uint32_t blks_to_load = bswap16(s.sector_count) >> ET_SECTOR_SHIFT;
923 long real_size = iso_get_file_size(bswap32(s.load_rba));
924
925 if (real_size > 0) {
926 /* Round up blocks to load */
927 blks_to_load = (real_size + ISO_SECTOR_SIZE - 1) / ISO_SECTOR_SIZE;
928 puts("ISO boot image size verified");
929 } else {
930 puts("ISO boot image size could not be verified");
931 if (real_size < 0) {
932 return;
933 }
934 }
935
936 if (read_iso_boot_image(bswap32(s.load_rba),
937 (void *)((uint64_t)bswap16(s.load_segment)),
938 blks_to_load)) {
939 return;
940 }
941
942 jump_to_low_kernel();
943 }
944
find_iso_bc(void)945 static uint32_t find_iso_bc(void)
946 {
947 IsoVolDesc *vd = (IsoVolDesc *)sec;
948 uint32_t block_num = ISO_PRIMARY_VD_SECTOR;
949
950 if (virtio_read_many(block_num++, sec, 1)) {
951 /* If primary vd cannot be read, there is no boot catalog */
952 return 0;
953 }
954
955 while (is_iso_vd_valid(vd) && vd->type != VOL_DESC_TERMINATOR) {
956 if (vd->type == VOL_DESC_TYPE_BOOT) {
957 IsoVdElTorito *et = &vd->vd.boot;
958
959 if (!memcmp(&et->el_torito[0], el_torito_magic, 32)) {
960 return bswap32(et->bc_offset);
961 }
962 }
963 if (virtio_read(block_num++, sec)) {
964 puts("Failed to read ISO volume descriptor");
965 return 0;
966 }
967 }
968
969 return 0;
970 }
971
find_iso_bc_entry(uint32_t offset)972 static IsoBcSection *find_iso_bc_entry(uint32_t offset)
973 {
974 IsoBcEntry *e = (IsoBcEntry *)sec;
975 int i;
976 unsigned int loadparm = get_loadparm_index();
977
978 if (!offset) {
979 return NULL;
980 }
981
982 if (virtio_read(offset, sec)) {
983 puts("Failed to read El Torito boot catalog");
984 return NULL;
985 }
986
987 if (!is_iso_bc_valid(e)) {
988 /* The validation entry is mandatory */
989 return NULL;
990 }
991
992 /*
993 * Each entry has 32 bytes size, so one sector cannot contain > 64 entries.
994 * We consider only boot catalogs with no more than 64 entries.
995 */
996 for (i = 1; i < ISO_BC_ENTRY_PER_SECTOR; i++) {
997 if (e[i].id == ISO_BC_BOOTABLE_SECTION) {
998 if (is_iso_bc_entry_compatible(&e[i].body.sect)) {
999 if (loadparm <= 1) {
1000 /* found, default, or unspecified */
1001 return &e[i].body.sect;
1002 }
1003 loadparm--;
1004 }
1005 }
1006 }
1007
1008 return NULL;
1009 }
1010
ipl_iso_el_torito(void)1011 static int ipl_iso_el_torito(void)
1012 {
1013 uint32_t offset = find_iso_bc();
1014 if (!offset) {
1015 return 0;
1016 }
1017
1018 IsoBcSection *s = find_iso_bc_entry(offset);
1019
1020 if (s) {
1021 load_iso_bc_entry(s); /* only return in error */
1022 return -1;
1023 }
1024
1025 puts("No suitable boot entry found on ISO-9660 media!");
1026 return -EIO;
1027 }
1028
1029 /**
1030 * Detect whether we're trying to boot from an .ISO image.
1031 * These always have a signature string "CD001" at offset 0x8001.
1032 */
has_iso_signature(void)1033 static bool has_iso_signature(void)
1034 {
1035 int blksize = virtio_get_block_size();
1036
1037 if (!blksize || virtio_read(0x8000 / blksize, sec)) {
1038 return false;
1039 }
1040
1041 return !memcmp("CD001", &sec[1], 5);
1042 }
1043
1044 /***********************************************************************
1045 * Bus specific IPL sequences
1046 */
1047
zipl_load_vblk(void)1048 static int zipl_load_vblk(void)
1049 {
1050 int blksize = virtio_get_block_size();
1051
1052 if (blksize == VIRTIO_ISO_BLOCK_SIZE || has_iso_signature()) {
1053 if (blksize != VIRTIO_ISO_BLOCK_SIZE) {
1054 virtio_assume_iso9660();
1055 }
1056 if (ipl_iso_el_torito()) {
1057 return 0;
1058 }
1059 }
1060
1061 if (blksize != VIRTIO_DASD_DEFAULT_BLOCK_SIZE) {
1062 puts("Using guessed DASD geometry.");
1063 virtio_assume_eckd();
1064 }
1065 return ipl_eckd();
1066 }
1067
zipl_load_vscsi(void)1068 static int zipl_load_vscsi(void)
1069 {
1070 if (virtio_get_block_size() == VIRTIO_ISO_BLOCK_SIZE) {
1071 /* Is it an ISO image in non-CD drive? */
1072 if (ipl_iso_el_torito()) {
1073 return 0;
1074 }
1075 }
1076
1077 puts("Using guessed DASD geometry.");
1078 virtio_assume_eckd();
1079 return ipl_eckd();
1080 }
1081
1082 /***********************************************************************
1083 * IPL starts here
1084 */
1085
zipl_load(void)1086 void zipl_load(void)
1087 {
1088 VDev *vdev = virtio_get_device();
1089
1090 if (vdev->is_cdrom) {
1091 ipl_iso_el_torito();
1092 puts("Failed to IPL this ISO image!");
1093 return;
1094 }
1095
1096 if (virtio_get_device_type() == VIRTIO_ID_NET) {
1097 netmain();
1098 puts("Failed to IPL from this network!");
1099 return;
1100 }
1101
1102 if (ipl_scsi()) {
1103 puts("Failed to IPL from this SCSI device!");
1104 return;
1105 }
1106
1107 switch (virtio_get_device_type()) {
1108 case VIRTIO_ID_BLOCK:
1109 zipl_load_vblk();
1110 break;
1111 case VIRTIO_ID_SCSI:
1112 zipl_load_vscsi();
1113 break;
1114 default:
1115 puts("Unknown IPL device type!");
1116 return;
1117 }
1118
1119 puts("zIPL load failed!");
1120 }
1121