1/*
2 * Copyright 2022, Haiku, Inc. All rights reserved.
3 * Distributed under the terms of the MIT License.
4 *
5 * Authors:
6 *		Trung Nguyen, trungnt282910@gmail.com
7 */
8
9
10#include <kernel/image.h>
11#include <link.h>
12#include <stddef.h>
13
14
15#if B_HAIKU_32_BIT
16	typedef Elf32_Ehdr Elf_Ehdr;
17#elif B_HAIKU_64_BIT
18	typedef Elf64_Ehdr Elf_Ehdr;
19#endif
20
21
22// While get_next_image_info does not return the address of
23// the ELF header, it does return the first page of the image's
24// text segment (defined by runtime_loader as the first loaded page
25// with read-only protection). For most images produced by
26// normal compilers, including Haiku ELF files, the file header
27// is always loaded at the beginning of the text segment.
28//
29// We can therefore take advantage of this fact and populate
30// struct dl_phdr_info.
31int
32dl_iterate_phdr(int (*callback)(struct dl_phdr_info* info, size_t size, void* data), void* data)
33{
34	image_info info;
35	int32 cookie = 0;
36	int status;
37
38	struct dl_phdr_info phdr_info;
39
40	while (get_next_image_info(0, &cookie, &info) == B_OK) {
41		const Elf_Ehdr* header = (const Elf_Ehdr*)info.text;
42
43		// Check for the special commpage info (which is not an ELF image),
44		// and also guard against any maliciously crafted file which
45		// does not load its header in memory.
46		if (!IS_ELF(*header))
47			continue;
48
49		phdr_info.dlpi_addr = (Elf_Addr)info.text;
50		phdr_info.dlpi_name = info.name;
51		phdr_info.dlpi_phnum = header->e_phnum;
52		phdr_info.dlpi_phdr = (const Elf_Phdr*)((const char*)info.text + header->e_phoff);
53
54		status = callback(&phdr_info, sizeof(phdr_info), data);
55
56		if (status != 0)
57			return status;
58	}
59
60	return 0;
61}
62