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
|
/* $OpenBSD: clean-elf.c,v 1.2 2003/11/03 07:01:33 david Exp $ */
/*
* Public domain. I don't even want my name on this.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <err.h>
#include <elf_abi.h>
#include <fcntl.h>
int
elf_is_okay(Elf_Ehdr *ehdr)
{
int retval = 0;
/*
* We need to check magic, class size, endianess,
* and version before we look at the rest of the
* Elf_Ehdr structure. These few elements are
* represented in a machine independent fashion.
*/
if (IS_ELF(*ehdr) &&
ehdr->e_ident[EI_CLASS] == ELF_TARG_CLASS &&
ehdr->e_ident[EI_DATA] == ELF_TARG_DATA &&
ehdr->e_ident[EI_VERSION] == ELF_TARG_VER) {
/* Now check the machine dependant header */
if (ehdr->e_machine == ELF_TARG_MACH &&
ehdr->e_version == ELF_TARG_VER)
retval = 1;
}
return retval;
}
void
cleanit(caddr_t addr)
{
Elf_Ehdr *ehdr;
Elf_Shdr *shdr;
char *strtab;
int i;
ehdr = (Elf_Ehdr *)addr;
shdr = (Elf_Shdr *)(addr + ehdr->e_shoff);
strtab = shdr[ehdr->e_shstrndx].sh_offset + addr;
/*
* Simple. find a .text section, verify that the next section is
* .rodata and merge them.
*/
for (i = 0; i < ehdr->e_shnum; i++) {
Elf_Shdr *t = &shdr[i];
Elf_Shdr *r = &shdr[i + 1];
#if 0
printf("foo: %s %d\n", strtab + t->sh_name, t->sh_type);
continue;
#endif
if (strcmp(strtab + t->sh_name, ".text"))
continue;
if (strcmp(strtab + r->sh_name, ".rodata"))
errx(1, "sorry, rodata merge not possible.");
t->sh_size += r->sh_size + (r->sh_offset - t->sh_offset - t->sh_size);
r->sh_type = SHT_NULL;
r->sh_name = 0;
}
}
int
main(int argc, char **argv)
{
int fd;
void *addr;
off_t len;
int pgsz = getpagesize();
if (argc != 2)
errx(1, "usage");
if ((fd = open(argv[1], O_RDWR)) < 0)
err(1, "open");
if ((len = lseek(fd, 0, SEEK_END)) < 0)
err(1, "lseek");
len = ((len + pgsz - 1) & ~(pgsz - 1));
if ((addr = mmap(0, len, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0)) ==
MAP_FAILED)
err(1, "mmap");
if (!elf_is_okay((Elf_Ehdr *)addr))
errx(1, "not an elf file");
cleanit(addr);
msync(addr, len, MS_SYNC|MS_INVALIDATE);
close(fd);
return (0);
}
|
