blob: 88b61a71d94328c51cf75601971a45f9c929b0ac (
plain)
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
|
#include "lib/kio.h"
#include <lib.h>
#include <elf.h>
#include <comus/mboot.h>
#include "mboot.h"
#define MULTIBOOT_TAG_TYPE_ELF_SECTIONS 9
struct multiboot_tag_elf_sections {
uint32_t type;
uint32_t size;
uint32_t num;
uint32_t entsize;
uint32_t shndx;
Elf64_Shdr sections[];
};
static struct multiboot_tag_elf_sections *elf = NULL;
static Elf64_Shdr *symtab = NULL;
static Elf64_Shdr *symstrtab = NULL;
static Elf64_Shdr *mboot_get_elf_sec(uint32_t sh_type)
{
for (uint32_t i = 0; i < elf->num; i++) {
Elf64_Shdr *ent = &elf->sections[i];
if (ent->sh_type == sh_type)
return ent;
}
return NULL;
}
static int mboot_load_elf(void)
{
void *tag = locate_mboot_table(MULTIBOOT_TAG_TYPE_ELF_SECTIONS);
if (tag == NULL)
return 1;
// found elf sections
elf = (struct multiboot_tag_elf_sections *)tag;
// load symtab
if ((symtab = mboot_get_elf_sec(SHT_SYMTAB)) == NULL)
return 1;
// load strsymtab
if ((symstrtab = mboot_get_elf_sec(symtab->sh_link)) == NULL)
return 1;
return 0;
}
const char *mboot_get_elf_sym(uint64_t addr)
{
if (symstrtab == NULL)
if (mboot_load_elf())
return NULL;
// walk symbol table
Elf64_Sym *syms = (Elf64_Sym *)symtab->sh_addr;
Elf64_Sym *best = NULL;
for (uint32_t i = 0; i < symtab->sh_size / symtab->sh_entsize; i++) {
Elf64_Sym *sym = &syms[i];
if (sym->st_value < addr)
continue;
if (best == NULL || (best->st_value < sym->st_value))
best = sym;
}
if (best != NULL) {
char *buf = (char *)symstrtab->sh_addr;
return &buf[best->st_name];
}
return "???";
}
|
