1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
|
/*
* This file is part of the coreboot project.
*
* Copyright (C) 2003 Eric W. Biederman <ebiederm@xmission.com>
* Copyright (C) 2009 Ron Minnich <rminnich@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
*/
#include <console/console.h>
#include <part/fallback_boot.h>
#include <boot/elf.h>
#include <boot/elf_boot.h>
#include <boot/coreboot_tables.h>
#include <ip_checksum.h>
#include <stream/read_bytes.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <cbfs.h>
#ifndef CONFIG_BIG_ENDIAN
#define ntohl(x) ( ((x&0xff)<<24) | ((x&0xff00)<<8) | \
((x&0xff0000) >> 8) | ((x&0xff000000) >> 24) )
#else
#define ntohl(x) (x)
#endif
/* Maximum physical address we can use for the coreboot bounce buffer.
*/
#ifndef MAX_ADDR
#define MAX_ADDR -1UL
#endif
extern unsigned char _ram_seg;
extern unsigned char _eram_seg;
struct segment {
struct segment *next;
struct segment *prev;
struct segment *phdr_next;
struct segment *phdr_prev;
unsigned long s_dstaddr;
unsigned long s_srcaddr;
unsigned long s_memsz;
unsigned long s_filesz;
};
struct verify_callback {
struct verify_callback *next;
int (*callback)(struct verify_callback *vcb,
Elf_ehdr *ehdr, Elf_phdr *phdr, struct segment *head);
unsigned long desc_offset;
unsigned long desc_addr;
};
struct ip_checksum_vcb {
struct verify_callback data;
unsigned short ip_checksum;
};
int cbfs_self_decompress(int algo, void *src,struct segment *new)
{
u8 *dst;
/* for uncompressed, it's easy: just point at the area in ROM */
if (algo == CBFS_COMPRESS_NONE) {
new->s_srcaddr = (u32) src;
new->s_filesz = new->s_memsz;
return 0;
}
/* for compression, let's keep it simple. We'll malloc the destination
* area and decompress to there. The compression overhead far outweighs
* any overhead for an extra copy.
*/
dst = malloc(new->s_memsz);
if (! dst)
return -1;
switch(algo) {
#ifdef CONFIG_COMPRESSION_LZMA
case CBFS_COMPRESS_LZMA: {
unsigned long ulzma(unsigned char *src, unsigned char *dst);
ulzma(src, dst);
break;
}
#endif
#ifdef CONFIG_COMPRESSION_NRV2B
case CBFS_COMPRESS_NRV2B: {
unsigned long unrv2b(u8 *src, u8 *dst, unsigned long *ilen_p);
unsigned long tmp;
unrv2b(src, dst, &tmp);
break;
}
#endif
default:
printk_info( "CBFS: Unknown compression type %d\n",
algo);
return -1;
}
new->s_srcaddr = (u32) dst;
new->s_filesz = new->s_memsz;
return 0;
}
/* The problem:
* Static executables all want to share the same addresses
* in memory because only a few addresses are reliably present on
* a machine, and implementing general relocation is hard.
*
* The solution:
* - Allocate a buffer twice the size of the coreboot image.
* - Anything that would overwrite coreboot copy into the lower half of
* the buffer.
* - After loading an ELF image copy coreboot to the upper half of the
* buffer.
* - Then jump to the loaded image.
*
* Benefits:
* - Nearly arbitrary standalone executables can be loaded.
* - Coreboot is preserved, so it can be returned to.
* - The implementation is still relatively simple,
* and much simpler then the general case implemented in kexec.
*
*/
static unsigned long get_bounce_buffer(struct lb_memory *mem)
{
unsigned long lb_size;
unsigned long mem_entries;
unsigned long buffer;
int i;
lb_size = (unsigned long)(&_eram_seg - &_ram_seg);
/* Double coreboot size so I have somewhere to place a copy to return to */
lb_size = lb_size + lb_size;
mem_entries = (mem->size - sizeof(*mem))/sizeof(mem->map[0]);
buffer = 0;
for(i = 0; i < mem_entries; i++) {
unsigned long mstart, mend;
unsigned long msize;
unsigned long tbuffer;
if (mem->map[i].type != LB_MEM_RAM)
continue;
if (unpack_lb64(mem->map[i].start) > MAX_ADDR)
continue;
if (unpack_lb64(mem->map[i].size) < lb_size)
continue;
mstart = unpack_lb64(mem->map[i].start);
msize = MAX_ADDR - mstart +1;
if (msize > unpack_lb64(mem->map[i].size))
msize = unpack_lb64(mem->map[i].size);
mend = mstart + msize;
tbuffer = mend - lb_size;
if (tbuffer < buffer)
continue;
buffer = tbuffer;
}
return buffer;
}
static int valid_area(struct lb_memory *mem, unsigned long buffer,
unsigned long start, unsigned long len)
{
/* Check through all of the memory segments and ensure
* the segment that was passed in is completely contained
* in RAM.
*/
int i;
unsigned long end = start + len;
unsigned long mem_entries = (mem->size - sizeof(*mem))/sizeof(mem->map[0]);
/* See if I conflict with the bounce buffer */
if (end >= buffer) {
return 0;
}
/* Walk through the table of valid memory ranges and see if I
* have a match.
*/
for(i = 0; i < mem_entries; i++) {
uint64_t mstart, mend;
uint32_t mtype;
mtype = mem->map[i].type;
mstart = unpack_lb64(mem->map[i].start);
mend = mstart + unpack_lb64(mem->map[i].size);
if ((mtype == LB_MEM_RAM) && (start < mend) && (end > mstart)) {
break;
}
if ((mtype == LB_MEM_TABLE) && (start < mend) && (end > mstart)) {
printk_err("Payload is overwriting Coreboot tables.\n");
break;
}
}
if (i == mem_entries) {
printk_err("No matching ram area found for range:\n");
printk_err(" [0x%016lx, 0x%016lx)\n", start, end);
printk_err("Ram areas\n");
for(i = 0; i < mem_entries; i++) {
uint64_t mstart, mend;
uint32_t mtype;
mtype = mem->map[i].type;
mstart = unpack_lb64(mem->map[i].start);
mend = mstart + unpack_lb64(mem->map[i].size);
printk_err(" [0x%016lx, 0x%016lx) %s\n",
(unsigned long)mstart,
(unsigned long)mend,
(mtype == LB_MEM_RAM)?"RAM":"Reserved");
}
return 0;
}
return 1;
}
static void relocate_segment(unsigned long buffer, struct segment *seg)
{
/* Modify all segments that want to load onto coreboot
* to load onto the bounce buffer instead.
*/
unsigned long lb_start = (unsigned long)&_ram_seg;
unsigned long lb_end = (unsigned long)&_eram_seg;
unsigned long start, middle, end;
printk_spew("lb: [0x%016lx, 0x%016lx)\n",
lb_start, lb_end);
start = seg->s_dstaddr;
middle = start + seg->s_filesz;
end = start + seg->s_memsz;
/* I don't conflict with coreboot so get out of here */
if ((end <= lb_start) || (start >= lb_end))
return;
printk_spew("segment: [0x%016lx, 0x%016lx, 0x%016lx)\n",
start, middle, end);
/* Slice off a piece at the beginning
* that doesn't conflict with coreboot.
*/
if (start < lb_start) {
struct segment *new;
unsigned long len = lb_start - start;
new = malloc(sizeof(*new));
*new = *seg;
new->s_memsz = len;
seg->s_memsz -= len;
seg->s_dstaddr += len;
seg->s_srcaddr += len;
if (seg->s_filesz > len) {
new->s_filesz = len;
seg->s_filesz -= len;
} else {
seg->s_filesz = 0;
}
/* Order by stream offset */
new->next = seg;
new->prev = seg->prev;
seg->prev->next = new;
seg->prev = new;
/* Order by original program header order */
new->phdr_next = seg;
new->phdr_prev = seg->phdr_prev;
seg->phdr_prev->phdr_next = new;
seg->phdr_prev = new;
/* compute the new value of start */
start = seg->s_dstaddr;
printk_spew(" early: [0x%016lx, 0x%016lx, 0x%016lx)\n",
new->s_dstaddr,
new->s_dstaddr + new->s_filesz,
new->s_dstaddr + new->s_memsz);
}
/* Slice off a piece at the end
* that doesn't conflict with coreboot
*/
if (end > lb_end) {
unsigned long len = lb_end - start;
struct segment *new;
new = malloc(sizeof(*new));
*new = *seg;
seg->s_memsz = len;
new->s_memsz -= len;
new->s_dstaddr += len;
new->s_srcaddr += len;
if (seg->s_filesz > len) {
seg->s_filesz = len;
new->s_filesz -= len;
} else {
new->s_filesz = 0;
}
/* Order by stream offset */
new->next = seg->next;
new->prev = seg;
seg->next->prev = new;
seg->next = new;
/* Order by original program header order */
new->phdr_next = seg->phdr_next;
new->phdr_prev = seg;
seg->phdr_next->phdr_prev = new;
seg->phdr_next = new;
/* compute the new value of end */
end = start + len;
printk_spew(" late: [0x%016lx, 0x%016lx, 0x%016lx)\n",
new->s_dstaddr,
new->s_dstaddr + new->s_filesz,
new->s_dstaddr + new->s_memsz);
}
/* Now retarget this segment onto the bounce buffer */
/* sort of explanation: the buffer is a 1:1 mapping to coreboot.
* so you will make the dstaddr be this buffer, and it will get copied
* later to where coreboot lives.
*/
seg->s_dstaddr = buffer + (seg->s_dstaddr - lb_start);
printk_spew(" bounce: [0x%016lx, 0x%016lx, 0x%016lx)\n",
seg->s_dstaddr,
seg->s_dstaddr + seg->s_filesz,
seg->s_dstaddr + seg->s_memsz);
}
static int build_self_segment_list(
struct segment *head,
unsigned long bounce_buffer, struct lb_memory *mem,
struct cbfs_payload *payload, u32 *entry)
{
struct segment *new;
struct segment *ptr;
u8 *data;
int datasize;
struct cbfs_payload_segment *segment, *first_segment;
memset(head, 0, sizeof(*head));
head->phdr_next = head->phdr_prev = head;
head->next = head->prev = head;
first_segment = segment = &payload->segments;
while(1) {
printk_debug("Segment %p\n", segment);
switch(segment->type) {
default: printk_emerg("Bad segment type %x\n", segment->type);
return -1;
case PAYLOAD_SEGMENT_PARAMS:
printk_info("found param section\n");
segment++;
continue;
case PAYLOAD_SEGMENT_CODE:
case PAYLOAD_SEGMENT_DATA:
printk_info( "%s: ", segment->type == PAYLOAD_SEGMENT_CODE ?
"code" : "data");
new = malloc(sizeof(*new));
new->s_dstaddr = ntohl((u32) segment->load_addr);
new->s_memsz = ntohl(segment->mem_len);
datasize = ntohl(segment->len);
/* figure out decompression, do it, get pointer to the area */
if (cbfs_self_decompress(ntohl(segment->compression),
((unsigned char *) first_segment) +
ntohl(segment->offset), new)) {
printk_emerg("cbfs_self_decompress failed\n");
return;
}
printk_debug("New segment dstaddr 0x%lx memsize 0x%lx srcaddr 0x%lx filesize 0x%lx\n",
new->s_dstaddr, new->s_memsz, new->s_srcaddr, new->s_filesz);
/* Clean up the values */
if (new->s_filesz > new->s_memsz) {
new->s_filesz = new->s_memsz;
}
printk_debug("(cleaned up) New segment addr 0x%lx size 0x%lx offset 0x%lx filesize 0x%lx\n",
new->s_dstaddr, new->s_memsz, new->s_srcaddr, new->s_filesz);
break;
case PAYLOAD_SEGMENT_BSS:
printk_info("BSS %p/%d\n", (void *) ntohl((u32) segment->load_addr),
ntohl(segment->mem_len));
new = malloc(sizeof(*new));
new->s_filesz = 0;
new->s_dstaddr = ntohl((u32) segment->load_addr);
new->s_memsz = ntohl(segment->mem_len);
break;
case PAYLOAD_SEGMENT_ENTRY:
printk_info("Entry %p\n", (void *) ntohl((u32) segment->load_addr));
*entry = (void *) ntohl((u32) segment->load_addr);
return 1;
}
segment++;
for(ptr = head->next; ptr != head; ptr = ptr->next) {
if (new->s_srcaddr < ntohl((u32) segment->load_addr))
break;
}
/* Order by stream offset */
new->next = ptr;
new->prev = ptr->prev;
ptr->prev->next = new;
ptr->prev = new;
/* Order by original program header order */
new->phdr_next = head;
new->phdr_prev = head->phdr_prev;
head->phdr_prev->phdr_next = new;
head->phdr_prev = new;
/* Verify the memory addresses in the segment are valid */
if (!valid_area(mem, bounce_buffer, new->s_dstaddr, new->s_memsz))
goto out;
/* Modify the segment to load onto the bounce_buffer if necessary.
*/
relocate_segment(bounce_buffer, new);
}
return 1;
out:
return 0;
}
static int load_self_segments(
struct segment *head, struct cbfs_payload *payload)
{
unsigned long offset;
struct segment *ptr;
offset = 0;
for(ptr = head->next; ptr != head; ptr = ptr->next) {
unsigned long skip_bytes, read_bytes;
unsigned char *dest, *middle, *end, *src;
byte_offset_t result;
printk_debug("Loading Segment: addr: 0x%016lx memsz: 0x%016lx filesz: 0x%016lx\n",
ptr->s_dstaddr, ptr->s_memsz, ptr->s_filesz);
/* Compute the boundaries of the segment */
dest = (unsigned char *)(ptr->s_dstaddr);
end = dest + ptr->s_memsz;
middle = dest + ptr->s_filesz;
src = ptr->s_srcaddr;
printk_spew("[ 0x%016lx, %016lx, 0x%016lx) <- %016lx\n",
(unsigned long)dest,
(unsigned long)middle,
(unsigned long)end,
(unsigned long)src);
/* Copy data from the initial buffer */
if (ptr->s_filesz) {
size_t len;
len = ptr->s_filesz;
memcpy(dest, src, len);
dest += len;
}
/* Zero the extra bytes between middle & end */
if (middle < end) {
printk_debug("Clearing Segment: addr: 0x%016lx memsz: 0x%016lx\n",
(unsigned long)middle, (unsigned long)(end - middle));
/* Zero the extra bytes */
memset(middle, 0, end - middle);
}
}
return 1;
out:
return 0;
}
int selfboot(struct lb_memory *mem, struct cbfs_payload *payload)
{
void *entry;
struct segment head;
unsigned long bounce_buffer;
/* Find a bounce buffer so I can load to coreboot's current location */
bounce_buffer = get_bounce_buffer(mem);
if (!bounce_buffer) {
printk_err("Could not find a bounce buffer...\n");
goto out;
}
/* Preprocess the self segments */
if (!build_self_segment_list(&head, bounce_buffer, mem, payload, &entry))
goto out;
/* Load the segments */
if (!load_self_segments(&head, payload))
goto out;
printk_spew("Loaded segments\n");
/* Reset to booting from this image as late as possible */
boot_successful();
printk_debug("Jumping to boot code at %p\n", entry);
post_code(0xfe);
/* Jump to kernel */
jmp_to_elf_entry(entry, bounce_buffer);
return 1;
out:
return 0;
}
|