From 598bbbd34ebbbc348a31142c62cecf8a93607e0a Mon Sep 17 00:00:00 2001 From: Trung Nguyen Date: Thu, 26 May 2022 20:48:56 +0700 Subject: [PATCH] libs/bsd: implemented dl_iterate_phdr dl_iterate_phdr now fills the first four fields of struct dl_phdr_info. The last four fields remain unimplemented, as it requires help from the runtime_loader. Change-Id: Id96a7c7ac05633a71b9fb62c98b3a40f7d4f255b Signed-off-by: Augustin Cavalier (cherry picked from commit 908107a15f63582157c7094be7273dbfffa1003c) Reviewed-on: https://review.haiku-os.org/c/haiku/+/5456 --- src/libs/bsd/Jamfile | 1 + src/libs/bsd/dl_iterate_phdr.c | 61 ++++++++++++++++++++++++++++++++++ 2 files changed, 62 insertions(+) create mode 100644 src/libs/bsd/dl_iterate_phdr.c diff --git a/src/libs/bsd/Jamfile b/src/libs/bsd/Jamfile index 0b3c70d046..9a300456b4 100644 --- a/src/libs/bsd/Jamfile +++ b/src/libs/bsd/Jamfile @@ -10,6 +10,7 @@ for architectureObject in [ MultiArchSubDirSetup ] { SharedLibrary [ MultiArchDefaultGristFiles libbsd.so ] : daemon.c + dl_iterate_phdr.c err.c explicit_bzero.c fgetln.c diff --git a/src/libs/bsd/dl_iterate_phdr.c b/src/libs/bsd/dl_iterate_phdr.c new file mode 100644 index 0000000000..540c7c3152 --- /dev/null +++ b/src/libs/bsd/dl_iterate_phdr.c @@ -0,0 +1,61 @@ +/* + * Copyright 2022, Haiku, Inc. All rights reserved. + * Distributed under the terms of the MIT License. + * + * Authors: + * Trung Nguyen, trungnt282910@gmail.com + */ + + +#include +#include +#include + + +#if B_HAIKU_32_BIT + typedef Elf32_Ehdr Elf_Ehdr; +#elif B_HAIKU_64_BIT + typedef Elf64_Ehdr Elf_Ehdr; +#endif + + +// While get_next_image_info does not return the address of +// the ELF header, it does return the first page of the image's +// text segment (defined by runtime_loader as the first loaded page +// with read-only protection). For most images produced by +// normal compilers, including Haiku ELF files, the file header +// is always loaded at the beginning of the text segment. +// +// We can therefore take advantage of this fact and populate +// struct dl_phdr_info. +int +dl_iterate_phdr(int (*callback)(struct dl_phdr_info* info, size_t size, void* data), void* data) +{ + image_info info; + int32 cookie = 0; + int status; + + struct dl_phdr_info phdr_info; + + while (get_next_image_info(0, &cookie, &info) == B_OK) { + const Elf_Ehdr* header = (const Elf_Ehdr*)info.text; + + // Check for the special commpage info (which is not an ELF image), + // and also guard against any maliciously crafted file which + // does not load its header in memory. + if (!IS_ELF(*header)) + continue; + + phdr_info.dlpi_addr = (Elf_Addr)info.text; + phdr_info.dlpi_name = info.name; + phdr_info.dlpi_phnum = header->e_phnum; + phdr_info.dlpi_phdr = (const Elf_Phdr*)((const char*)info.text + header->e_phoff); + + status = callback(&phdr_info, sizeof(phdr_info), data); + + if (status != 0) + return status; + } + + return 0; +}