mirror of
https://github.com/baldurk/renderdoc.git
synced 2026-05-06 10:00:40 +00:00
Add plthook for hooking libraries on linux even through DEEPBIND
* Based on a fork with slight added extra functionality at https://github.com/baldurk/plthook
This commit is contained in:
baldurk
@@ -98,3 +98,7 @@ RenderDoc also uses several external libraries and components which include thei
|
||||
- [include-bin](https://github.com/Marqin/include-bin)
|
||||
distributed under the zlib license.
|
||||
Copyright 2016, Hubert Jarosz
|
||||
|
||||
- [plthook](https://github.com/kubo/plthook)
|
||||
distributed under the 2-clause BSD license.
|
||||
Copyright 2013-2014, Kubo Takehiro
|
||||
|
||||
@@ -74,7 +74,11 @@ The following libraries and components are incorporated into RenderDoc, listed h
|
||||
|
||||
.. |cmdline_link| raw:: html
|
||||
|
||||
<a href="https://github.com/tanakh/cmdline target="_blank">cmdline</a>
|
||||
<a href="https://github.com/tanakh/cmdline" target="_blank">cmdline</a>
|
||||
|
||||
.. |plthook_link| raw:: html
|
||||
|
||||
<a href="https://github.com/kubo/plthook" target="_blank">plthook</a>
|
||||
|
||||
* |mhook_link| DLL hooking library, used to inject RenderDoc into applications
|
||||
* |treeview_link| An invaluable control filling a much needed niche in .NET winforms.
|
||||
@@ -93,6 +97,7 @@ The following libraries and components are incorporated into RenderDoc, listed h
|
||||
* |glslang_link| Used for compiling GLSL to SPIR-V.
|
||||
* |qt_link| Used for QRenderDoc replay UI program.
|
||||
* |cmdline_link| Used for parsing command line arguments to renderdoccmd.
|
||||
* |plthook_link| Used for hooking some libraries loaded with DEEPBIND on linux.
|
||||
|
||||
Thanks
|
||||
------
|
||||
|
||||
Binary file not shown.
Vendored
+58
@@ -0,0 +1,58 @@
|
||||
PLT Hook
|
||||
========
|
||||
|
||||
What is plthook.
|
||||
----------------
|
||||
|
||||
A utility library to hook library function calls issued by
|
||||
specified object files (executable and libraries).
|
||||
|
||||
Usage
|
||||
-----
|
||||
|
||||
If you have a library `libfoo.so.1` and want to intercept
|
||||
a function call `recv()` without modifying the library,
|
||||
put `plthook.c` (or `plthook_win32.c` for Windows) and `plthook.h`
|
||||
in your source tree and add the following code.
|
||||
|
||||
|
||||
static ssize_t my_recv(int sockfd, void *buf, size_t len, int flags)
|
||||
{
|
||||
ssize_t rv;
|
||||
|
||||
... do your task: logging, etc. ...
|
||||
rv = recv(sockfd, buf, len, flags); /* call real recv(). */
|
||||
... do your task: logging, check received data, etc. ...
|
||||
return rv;
|
||||
}
|
||||
|
||||
int install_hook_function()
|
||||
{
|
||||
plthook_t *plthook;
|
||||
|
||||
if (plthook_open(&plthook, "libfoo.so.1") != 0) {
|
||||
printf("plthook_open error: %s\n", plthook_error());
|
||||
return -1;
|
||||
}
|
||||
if (plthook_replace(plthook, "recv", (void*)my_recv, NULL) != 0) {
|
||||
printf("plthook_replace error: %s\n", plthook_error());
|
||||
plthook_close(plthook);
|
||||
return -1;
|
||||
}
|
||||
plthook_close(plthook);
|
||||
return 0;
|
||||
}
|
||||
|
||||
Supported Platforms
|
||||
-------------------
|
||||
|
||||
* Linux i386 and x86_64 by plthook_elf.c
|
||||
* Windows 32-bit and x64 (MSVC, Mingw32 and Cygwin) by plthook_win32.c
|
||||
* OS X (tested on Mavericks) by plthook_osx.c
|
||||
* Solaris x86_64 by plthook_elf.c
|
||||
* FreeBSD i386 and x86_64 except i386 program on x86_64 OS by plthook_elf.c
|
||||
|
||||
License
|
||||
-------
|
||||
|
||||
2-clause BSD-style license.
|
||||
Vendored
+65
@@ -0,0 +1,65 @@
|
||||
/* -*- indent-tabs-mode: nil -*-
|
||||
*
|
||||
* plthook.h -- the header file of plthook
|
||||
*
|
||||
* URL: https://github.com/kubo/plthook
|
||||
*
|
||||
* ------------------------------------------------------
|
||||
*
|
||||
* Copyright 2013-2014 Kubo Takehiro <kubo@jiubao.org>
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without modification, are
|
||||
* permitted provided that the following conditions are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright notice, this list of
|
||||
* conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
|
||||
* of conditions and the following disclaimer in the documentation and/or other materials
|
||||
* provided with the distribution.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ''AS IS'' AND ANY EXPRESS OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
|
||||
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> OR
|
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
||||
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
||||
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
|
||||
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
|
||||
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
|
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||||
*
|
||||
* The views and conclusions contained in the software and documentation are those of the
|
||||
* authors and should not be interpreted as representing official policies, either expressed
|
||||
* or implied, of the authors.
|
||||
*
|
||||
*/
|
||||
#ifndef PLTHOOK_H
|
||||
#define PLTHOOK_H 1
|
||||
|
||||
#define PLTHOOK_SUCCESS 0
|
||||
#define PLTHOOK_FILE_NOT_FOUND 1
|
||||
#define PLTHOOK_INVALID_FILE_FORMAT 2
|
||||
#define PLTHOOK_FUNCTION_NOT_FOUND 3
|
||||
#define PLTHOOK_INVALID_ARGUMENT 4
|
||||
#define PLTHOOK_OUT_OF_MEMORY 5
|
||||
#define PLTHOOK_INTERNAL_ERROR 6
|
||||
|
||||
typedef struct plthook plthook_t;
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
int plthook_open(plthook_t **plthook_out, const char *filename);
|
||||
int plthook_open_by_handle(plthook_t **plthook_out, void *handle);
|
||||
int plthook_open_by_address(plthook_t **plthook_out, void *address);
|
||||
int plthook_enum(plthook_t *plthook, unsigned int *pos, const char **name_out, void ***addr_out);
|
||||
int plthook_replace(plthook_t *plthook, const char *funcname, void *funcaddr, void **oldfunc);
|
||||
void plthook_close(plthook_t *plthook);
|
||||
const char *plthook_error(void);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}; /* extern "C" */
|
||||
#endif
|
||||
|
||||
#endif
|
||||
+611
@@ -0,0 +1,611 @@
|
||||
/* -*- indent-tabs-mode: nil -*-
|
||||
*
|
||||
* plthook_elf.c -- implemention of plthook for ELF format
|
||||
*
|
||||
* URL: https://github.com/kubo/plthook
|
||||
*
|
||||
* ------------------------------------------------------
|
||||
*
|
||||
* Copyright 2013-2016 Kubo Takehiro <kubo@jiubao.org>
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without modification, are
|
||||
* permitted provided that the following conditions are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright notice, this list of
|
||||
* conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
|
||||
* of conditions and the following disclaimer in the documentation and/or other materials
|
||||
* provided with the distribution.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ''AS IS'' AND ANY EXPRESS OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
|
||||
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> OR
|
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
||||
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
||||
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
|
||||
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
|
||||
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
|
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
||||
*
|
||||
* The views and conclusions contained in the software and documentation are those of the
|
||||
* authors and should not be interpreted as representing official policies, either expressed
|
||||
* or implied, of the authors.
|
||||
*
|
||||
*/
|
||||
#define _GNU_SOURCE
|
||||
#include <stdio.h>
|
||||
#include <stdarg.h>
|
||||
#include <stdlib.h>
|
||||
#include <unistd.h>
|
||||
#include <string.h>
|
||||
#include <limits.h>
|
||||
#include <sys/types.h>
|
||||
#include <sys/stat.h>
|
||||
#include <sys/mman.h>
|
||||
#include <fcntl.h>
|
||||
#include <errno.h>
|
||||
#include <dlfcn.h>
|
||||
#ifdef __sun
|
||||
#include <procfs.h>
|
||||
#define ELF_TARGET_ALL
|
||||
#endif /* __sun */
|
||||
#include <elf.h>
|
||||
#include <link.h>
|
||||
#include "plthook.h"
|
||||
|
||||
#ifndef __GNUC__
|
||||
#define __attribute__(arg)
|
||||
#endif
|
||||
|
||||
#if defined __linux__
|
||||
#define ELF_OSABI ELFOSABI_SYSV
|
||||
#define ELF_OSABI_ALT ELFOSABI_LINUX
|
||||
#elif defined __sun
|
||||
#define ELF_OSABI ELFOSABI_SOLARIS
|
||||
#elif defined __FreeBSD__
|
||||
#define ELF_OSABI ELFOSABI_FREEBSD
|
||||
#if defined __i386__ && __ELF_WORD_SIZE == 64
|
||||
#error 32-bit application on 64-bit OS is not supported.
|
||||
#endif
|
||||
#else
|
||||
#error unsupported OS
|
||||
#endif
|
||||
|
||||
#if defined __x86_64__ || defined __x86_64
|
||||
#define ELF_DATA ELFDATA2LSB
|
||||
#define E_MACHINE EM_X86_64
|
||||
#ifdef R_X86_64_JUMP_SLOT
|
||||
#define R_JUMP_SLOT R_X86_64_JUMP_SLOT
|
||||
#else
|
||||
#define R_JUMP_SLOT R_X86_64_JMP_SLOT
|
||||
#endif
|
||||
#define SHT_PLT_REL SHT_RELA
|
||||
#define Elf_Plt_Rel Elf_Rela
|
||||
#define PLT_SECTION_NAME ".rela.plt"
|
||||
#elif defined __i386__ || defined __i386
|
||||
#define ELF_DATA ELFDATA2LSB
|
||||
#define E_MACHINE EM_386
|
||||
#define R_JUMP_SLOT R_386_JMP_SLOT
|
||||
#define SHT_PLT_REL SHT_REL
|
||||
#define Elf_Plt_Rel Elf_Rel
|
||||
#define PLT_SECTION_NAME ".rel.plt"
|
||||
#else
|
||||
#error E_MACHINE is not defined.
|
||||
#endif
|
||||
|
||||
#if defined __LP64__
|
||||
#ifndef ELF_CLASS
|
||||
#define ELF_CLASS ELFCLASS64
|
||||
#endif
|
||||
#define SIZE_T_FMT "lu"
|
||||
#define Elf_Half Elf64_Half
|
||||
#define Elf_Addr Elf64_Addr
|
||||
#define Elf_Ehdr Elf64_Ehdr
|
||||
#define Elf_Phdr Elf64_Phdr
|
||||
#define Elf_Shdr Elf64_Shdr
|
||||
#define Elf_Sym Elf64_Sym
|
||||
#define Elf_Rel Elf64_Rel
|
||||
#define Elf_Rela Elf64_Rela
|
||||
#ifndef ELF_R_SYM
|
||||
#define ELF_R_SYM ELF64_R_SYM
|
||||
#endif
|
||||
#ifndef ELF_R_TYPE
|
||||
#define ELF_R_TYPE ELF64_R_TYPE
|
||||
#endif
|
||||
#else /* __LP64__ */
|
||||
#ifndef ELF_CLASS
|
||||
#define ELF_CLASS ELFCLASS32
|
||||
#endif
|
||||
#define SIZE_T_FMT "u"
|
||||
#define Elf_Half Elf32_Half
|
||||
#define Elf_Addr Elf32_Addr
|
||||
#define Elf_Ehdr Elf32_Ehdr
|
||||
#define Elf_Phdr Elf32_Phdr
|
||||
#define Elf_Shdr Elf32_Shdr
|
||||
#define Elf_Sym Elf32_Sym
|
||||
#define Elf_Rel Elf32_Rel
|
||||
#define Elf_Rela Elf32_Rela
|
||||
#ifndef ELF_R_SYM
|
||||
#define ELF_R_SYM ELF32_R_SYM
|
||||
#endif
|
||||
#ifndef ELF_R_TYPE
|
||||
#define ELF_R_TYPE ELF32_R_TYPE
|
||||
#endif
|
||||
#endif /* __LP64__ */
|
||||
|
||||
struct plthook {
|
||||
const char *base;
|
||||
const Elf_Phdr *phdr;
|
||||
size_t phnum;
|
||||
Elf_Shdr *shdr;
|
||||
size_t shnum;
|
||||
char *shstrtab;
|
||||
size_t shstrtab_size;
|
||||
const Elf_Sym *dynsym;
|
||||
size_t dynsym_cnt;
|
||||
const char *dynstr;
|
||||
size_t dynstr_size;
|
||||
const Elf_Plt_Rel *plt;
|
||||
size_t plt_cnt;
|
||||
#ifdef PT_GNU_RELRO
|
||||
const char *relro_start;
|
||||
const char *relro_end;
|
||||
#endif
|
||||
};
|
||||
|
||||
static char errmsg[512];
|
||||
|
||||
#ifdef PT_GNU_RELRO
|
||||
static size_t page_size;
|
||||
#endif
|
||||
|
||||
static int plthook_open_executable(plthook_t **plthook_out);
|
||||
static int plthook_open_shared_library(plthook_t **plthook_out, const char *filename);
|
||||
static int plthook_open_real(plthook_t **plthook_out, const char *base, const char *filename);
|
||||
static int check_elf_header(const Elf_Ehdr *ehdr);
|
||||
static int find_section(plthook_t *image, const char *name, const Elf_Shdr **out);
|
||||
static void set_errmsg(const char *fmt, ...) __attribute__((__format__ (__printf__, 1, 2)));
|
||||
|
||||
int plthook_open(plthook_t **plthook_out, const char *filename)
|
||||
{
|
||||
*plthook_out = NULL;
|
||||
if (filename == NULL) {
|
||||
return plthook_open_executable(plthook_out);
|
||||
} else {
|
||||
return plthook_open_shared_library(plthook_out, filename);
|
||||
}
|
||||
}
|
||||
|
||||
int plthook_open_by_handle(plthook_t **plthook_out, void *hndl)
|
||||
{
|
||||
struct link_map *lmap = NULL;
|
||||
|
||||
if (hndl == NULL) {
|
||||
set_errmsg("NULL handle");
|
||||
return PLTHOOK_FILE_NOT_FOUND;
|
||||
}
|
||||
if (dlinfo(hndl, RTLD_DI_LINKMAP, &lmap) != 0) {
|
||||
set_errmsg("dlinfo error");
|
||||
return PLTHOOK_FILE_NOT_FOUND;
|
||||
}
|
||||
return plthook_open_real(plthook_out, (const char*)lmap->l_addr, lmap->l_name);
|
||||
}
|
||||
|
||||
int plthook_open_by_address(plthook_t **plthook_out, void *address)
|
||||
{
|
||||
Dl_info info;
|
||||
|
||||
*plthook_out = NULL;
|
||||
if (dladdr(address, &info) == 0) {
|
||||
set_errmsg("dladdr error");
|
||||
return PLTHOOK_FILE_NOT_FOUND;
|
||||
}
|
||||
return plthook_open_real(plthook_out, info.dli_fbase, info.dli_fname);
|
||||
}
|
||||
|
||||
static int plthook_open_executable(plthook_t **plthook_out)
|
||||
{
|
||||
#if defined __linux__
|
||||
/* Open the main program. */
|
||||
char buf[128];
|
||||
FILE *fp = fopen("/proc/self/maps", "r");
|
||||
unsigned long base;
|
||||
|
||||
if (fp == NULL) {
|
||||
set_errmsg("Could not open /proc/self/maps: %s",
|
||||
strerror(errno));
|
||||
return PLTHOOK_INTERNAL_ERROR;
|
||||
}
|
||||
if (fgets(buf, sizeof(buf), fp) == NULL) {
|
||||
set_errmsg("Could not read /proc/self/maps: %s",
|
||||
strerror(errno));
|
||||
fclose(fp);
|
||||
return PLTHOOK_INTERNAL_ERROR;
|
||||
}
|
||||
fclose(fp);
|
||||
if (sscanf(buf, "%lx-%*x r-xp %*x %*x:%*x %*u ", &base) != 1) {
|
||||
set_errmsg("invalid /proc/self/maps format: %s", buf);
|
||||
return PLTHOOK_INTERNAL_ERROR;
|
||||
}
|
||||
return plthook_open_real(plthook_out, (const char*)base, "/proc/self/exe");
|
||||
#elif defined __sun
|
||||
prmap_t prmap;
|
||||
pid_t pid = getpid();
|
||||
char fname[128];
|
||||
int fd;
|
||||
|
||||
sprintf(fname, "/proc/%d/map", pid);
|
||||
fd = open(fname, O_RDONLY);
|
||||
if (fd == -1) {
|
||||
set_errmsg("Could not open %s: %s", fname,
|
||||
strerror(errno));
|
||||
return PLTHOOK_INTERNAL_ERROR;
|
||||
}
|
||||
if (read(fd, &prmap, sizeof(prmap)) != sizeof(prmap)) {
|
||||
set_errmsg("Could not read %s: %s", fname,
|
||||
strerror(errno));
|
||||
close(fd);
|
||||
return PLTHOOK_INTERNAL_ERROR;
|
||||
}
|
||||
close(fd);
|
||||
sprintf(fname, "/proc/%d/object/a.out", pid);
|
||||
return plthook_open_real(plthook_out, (const char*)prmap.pr_vaddr, fname);
|
||||
#elif defined __FreeBSD__
|
||||
return plthook_open_shared_library(plthook_out, NULL);
|
||||
#else
|
||||
#error unsupported OS
|
||||
#endif
|
||||
}
|
||||
|
||||
static int plthook_open_shared_library(plthook_t **plthook_out, const char *filename)
|
||||
{
|
||||
void *hndl = dlopen(filename, RTLD_LAZY | RTLD_NOLOAD);
|
||||
struct link_map *lmap = NULL;
|
||||
|
||||
if (hndl == NULL) {
|
||||
set_errmsg("dlopen error: %s", dlerror());
|
||||
return PLTHOOK_FILE_NOT_FOUND;
|
||||
}
|
||||
if (dlinfo(hndl, RTLD_DI_LINKMAP, &lmap) != 0) {
|
||||
set_errmsg("dlinfo error");
|
||||
dlclose(hndl);
|
||||
return PLTHOOK_FILE_NOT_FOUND;
|
||||
}
|
||||
dlclose(hndl);
|
||||
return plthook_open_real(plthook_out, (const char*)lmap->l_addr, lmap->l_name);
|
||||
}
|
||||
|
||||
static int plthook_open_real(plthook_t **plthook_out, const char *base, const char *filename)
|
||||
{
|
||||
const Elf_Ehdr *ehdr = (Elf_Ehdr *)base;
|
||||
const Elf_Shdr *shdr;
|
||||
size_t shdr_size;
|
||||
int fd = -1;
|
||||
off_t offset;
|
||||
plthook_t *plthook;
|
||||
int rv;
|
||||
#ifdef PT_GNU_RELRO
|
||||
size_t idx;
|
||||
#endif
|
||||
|
||||
if (base == NULL) {
|
||||
set_errmsg("The base address is zero.");
|
||||
return PLTHOOK_FILE_NOT_FOUND;
|
||||
}
|
||||
|
||||
if (filename == NULL) {
|
||||
set_errmsg("failed to get the file name on the disk.");
|
||||
return PLTHOOK_FILE_NOT_FOUND;
|
||||
}
|
||||
|
||||
plthook = calloc(1, sizeof(plthook_t));
|
||||
if (plthook == NULL) {
|
||||
set_errmsg("failed to allocate memory: %" SIZE_T_FMT " bytes", sizeof(plthook_t));
|
||||
return PLTHOOK_OUT_OF_MEMORY;
|
||||
}
|
||||
|
||||
/* sanity check */
|
||||
rv = check_elf_header(ehdr);
|
||||
if (rv != 0) {
|
||||
goto error_exit;
|
||||
}
|
||||
if (ehdr->e_type == ET_DYN) {
|
||||
plthook->base = base;
|
||||
}
|
||||
plthook->phdr = (const Elf_Phdr *)(plthook->base + ehdr->e_phoff);
|
||||
plthook->phnum = ehdr->e_phnum;
|
||||
fd = open(filename, O_RDONLY, 0);
|
||||
if (fd == -1) {
|
||||
set_errmsg("Could not open %s: %s", filename, strerror(errno));
|
||||
rv = PLTHOOK_FILE_NOT_FOUND;
|
||||
goto error_exit;
|
||||
}
|
||||
shdr_size = ehdr->e_shnum * ehdr->e_shentsize;
|
||||
plthook->shdr = calloc(1, shdr_size);
|
||||
if (plthook->shdr == NULL) {
|
||||
set_errmsg("failed to allocate memory: %" SIZE_T_FMT " bytes", shdr_size);
|
||||
rv = PLTHOOK_OUT_OF_MEMORY;
|
||||
goto error_exit;
|
||||
}
|
||||
offset = ehdr->e_shoff;
|
||||
if ((rv = lseek(fd, offset, SEEK_SET)) != offset) {
|
||||
set_errmsg("failed to seek to the section header table.");
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
if (read(fd, plthook->shdr, shdr_size) != shdr_size) {
|
||||
set_errmsg("failed to read the section header table.");
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
plthook->shnum = ehdr->e_shnum;
|
||||
plthook->shstrtab_size = plthook->shdr[ehdr->e_shstrndx].sh_size;
|
||||
plthook->shstrtab = malloc(plthook->shstrtab_size);
|
||||
if (plthook->shstrtab == NULL) {
|
||||
set_errmsg("failed to allocate memory: %" SIZE_T_FMT " bytes", plthook->shstrtab_size);
|
||||
rv = PLTHOOK_OUT_OF_MEMORY;
|
||||
goto error_exit;
|
||||
}
|
||||
offset = plthook->shdr[ehdr->e_shstrndx].sh_offset;
|
||||
if (lseek(fd, offset, SEEK_SET) != offset) {
|
||||
set_errmsg("failed to seek to the section header string table.");
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
if (read(fd, plthook->shstrtab, plthook->shstrtab_size) != plthook->shstrtab_size) {
|
||||
set_errmsg("failed to read the section header string table.");
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
#ifdef PT_GNU_RELRO
|
||||
if (page_size == 0) {
|
||||
page_size = sysconf(_SC_PAGESIZE);
|
||||
}
|
||||
offset = ehdr->e_phoff;
|
||||
if ((rv = lseek(fd, offset, SEEK_SET)) != offset) {
|
||||
set_errmsg("failed to seek to the program header table.");
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
for (idx = 0; idx < ehdr->e_phnum; idx++) {
|
||||
Elf_Phdr phdr;
|
||||
if (read(fd, &phdr, sizeof(phdr)) != sizeof(phdr)) {
|
||||
set_errmsg("failed to read the program header table.");
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
if (phdr.p_type == PT_GNU_RELRO) {
|
||||
plthook->relro_start = plthook->base + phdr.p_vaddr;
|
||||
plthook->relro_end = plthook->relro_start + phdr.p_memsz;
|
||||
}
|
||||
}
|
||||
#endif
|
||||
close(fd);
|
||||
fd = -1;
|
||||
|
||||
rv = find_section(plthook, ".dynsym", &shdr);
|
||||
if (rv != 0) {
|
||||
goto error_exit;
|
||||
}
|
||||
if (shdr->sh_type != SHT_DYNSYM) {
|
||||
set_errmsg("The type of .dynsym section should be SHT_DYNSYM but %d.", shdr->sh_type);
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
if (shdr->sh_entsize != sizeof(Elf_Sym)) {
|
||||
set_errmsg("The size of a section header entry should be sizeof(Elf_Sym)(%" SIZE_T_FMT ") but %" SIZE_T_FMT ".",
|
||||
sizeof(Elf_Sym), shdr->sh_entsize);
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
plthook->dynsym = (const Elf_Sym*)(plthook->base + shdr->sh_addr);
|
||||
plthook->dynsym_cnt = shdr->sh_size / shdr->sh_entsize;
|
||||
|
||||
rv = find_section(plthook, ".dynstr", &shdr);
|
||||
if (rv != 0) {
|
||||
goto error_exit;
|
||||
}
|
||||
if (shdr->sh_type != SHT_STRTAB) {
|
||||
set_errmsg("The type of .dynstrx section should be SHT_STRTAB but %d.", shdr->sh_type);
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
plthook->dynstr = (const char*)(plthook->base + shdr->sh_addr);
|
||||
plthook->dynstr_size = shdr->sh_size;
|
||||
|
||||
rv = find_section(plthook, PLT_SECTION_NAME, &shdr);
|
||||
if (rv != 0) {
|
||||
goto error_exit;
|
||||
}
|
||||
if (shdr->sh_entsize != sizeof(Elf_Plt_Rel)) {
|
||||
set_errmsg("invalid " PLT_SECTION_NAME " table entry size: %" SIZE_T_FMT, shdr->sh_entsize);
|
||||
rv = PLTHOOK_INVALID_FILE_FORMAT;
|
||||
goto error_exit;
|
||||
}
|
||||
plthook->plt = (Elf_Plt_Rel *)(plthook->base + shdr->sh_addr);
|
||||
plthook->plt_cnt = shdr->sh_size / sizeof(Elf_Plt_Rel);
|
||||
|
||||
*plthook_out = plthook;
|
||||
return 0;
|
||||
error_exit:
|
||||
if (fd != -1) {
|
||||
close(fd);
|
||||
}
|
||||
plthook_close(plthook);
|
||||
return rv;
|
||||
}
|
||||
|
||||
int plthook_enum(plthook_t *plthook, unsigned int *pos, const char **name_out, void ***addr_out)
|
||||
{
|
||||
while (*pos < plthook->plt_cnt) {
|
||||
const Elf_Plt_Rel *plt = plthook->plt + *pos;
|
||||
if (ELF_R_TYPE(plt->r_info) == R_JUMP_SLOT) {
|
||||
size_t idx = ELF_R_SYM(plt->r_info);
|
||||
|
||||
if (idx >= plthook->dynsym_cnt) {
|
||||
set_errmsg(".dynsym index %" SIZE_T_FMT " should be less than %" SIZE_T_FMT ".", idx, plthook->dynsym_cnt);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
idx = plthook->dynsym[idx].st_name;
|
||||
if (idx + 1 > plthook->dynstr_size) {
|
||||
set_errmsg("too big section header string table index: %" SIZE_T_FMT, idx);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
*name_out = plthook->dynstr + idx;
|
||||
*addr_out = (void**)(plthook->base + plt->r_offset);
|
||||
(*pos)++;
|
||||
return 0;
|
||||
}
|
||||
(*pos)++;
|
||||
}
|
||||
*name_out = NULL;
|
||||
*addr_out = NULL;
|
||||
return EOF;
|
||||
}
|
||||
|
||||
int plthook_replace(plthook_t *plthook, const char *funcname, void *funcaddr, void **oldfunc)
|
||||
{
|
||||
size_t funcnamelen = strlen(funcname);
|
||||
unsigned int pos = 0;
|
||||
const char *name;
|
||||
void **addr;
|
||||
int rv;
|
||||
|
||||
if (plthook == NULL) {
|
||||
set_errmsg("invalid argument: The first argument is null.");
|
||||
return PLTHOOK_INVALID_ARGUMENT;
|
||||
}
|
||||
while ((rv = plthook_enum(plthook, &pos, &name, &addr)) == 0) {
|
||||
if (strncmp(name, funcname, funcnamelen) == 0) {
|
||||
if (name[funcnamelen] == '\0' || name[funcnamelen] == '@') {
|
||||
#ifdef PT_GNU_RELRO
|
||||
void *maddr = NULL;
|
||||
if (plthook->relro_start <= (char*)addr && (char*)addr < plthook->relro_end) {
|
||||
maddr = (void*)((size_t)addr & ~(page_size - 1));
|
||||
if (mprotect(maddr, page_size, PROT_READ | PROT_WRITE) != 0) {
|
||||
set_errmsg("Could not change the process memory protection at %p: %s",
|
||||
maddr, strerror(errno));
|
||||
return PLTHOOK_INTERNAL_ERROR;
|
||||
}
|
||||
}
|
||||
#endif
|
||||
if (oldfunc) {
|
||||
*oldfunc = *addr;
|
||||
}
|
||||
*addr = funcaddr;
|
||||
#ifdef PT_GNU_RELRO
|
||||
if (maddr != NULL) {
|
||||
mprotect(maddr, page_size, PROT_READ);
|
||||
}
|
||||
#endif
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
}
|
||||
if (rv == EOF) {
|
||||
set_errmsg("no such function: %s", funcname);
|
||||
rv = PLTHOOK_FUNCTION_NOT_FOUND;
|
||||
}
|
||||
return rv;
|
||||
}
|
||||
|
||||
void plthook_close(plthook_t *plthook)
|
||||
{
|
||||
if (plthook != NULL) {
|
||||
free(plthook->shdr);
|
||||
free(plthook->shstrtab);
|
||||
free(plthook);
|
||||
}
|
||||
}
|
||||
|
||||
const char *plthook_error(void)
|
||||
{
|
||||
return errmsg;
|
||||
}
|
||||
|
||||
static int check_elf_header(const Elf_Ehdr *ehdr)
|
||||
{
|
||||
if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0) {
|
||||
set_errmsg("invalid file signature: 0x%02x,0x%02x,0x%02x,0x%02x",
|
||||
ehdr->e_ident[0], ehdr->e_ident[1], ehdr->e_ident[2], ehdr->e_ident[3]);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (ehdr->e_ident[EI_CLASS] != ELF_CLASS) {
|
||||
set_errmsg("invalid elf class: 0x%02x", ehdr->e_ident[EI_CLASS]);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (ehdr->e_ident[EI_DATA] != ELF_DATA) {
|
||||
set_errmsg("invalid elf data: 0x%02x", ehdr->e_ident[EI_DATA]);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (ehdr->e_ident[EI_VERSION] != EV_CURRENT) {
|
||||
set_errmsg("invalid elf version: 0x%02x", ehdr->e_ident[EI_VERSION]);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (ehdr->e_ident[EI_OSABI] != ELF_OSABI) {
|
||||
#ifdef ELF_OSABI_ALT
|
||||
if (ehdr->e_ident[EI_OSABI] != ELF_OSABI_ALT) {
|
||||
set_errmsg("invalid OS ABI: 0x%02x", ehdr->e_ident[EI_OSABI]);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
#else
|
||||
set_errmsg("invalid OS ABI: 0x%02x", ehdr->e_ident[EI_OSABI]);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
#endif
|
||||
}
|
||||
if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) {
|
||||
set_errmsg("invalid file type: 0x%04x", ehdr->e_type);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (ehdr->e_machine != E_MACHINE) {
|
||||
set_errmsg("invalid machine type: %u", ehdr->e_machine);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (ehdr->e_version != EV_CURRENT) {
|
||||
set_errmsg("invalid object file version: %u", ehdr->e_version);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (ehdr->e_ehsize != sizeof(Elf_Ehdr)) {
|
||||
set_errmsg("invalid elf header size: %u", ehdr->e_ehsize);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (ehdr->e_phentsize != sizeof(Elf_Phdr)) {
|
||||
set_errmsg("invalid program header table entry size: %u", ehdr->e_phentsize);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (ehdr->e_shentsize != sizeof(Elf_Shdr)) {
|
||||
set_errmsg("invalid section header table entry size: %u", ehdr->e_shentsize);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int find_section(plthook_t *image, const char *name, const Elf_Shdr **out)
|
||||
{
|
||||
const Elf_Shdr *shdr = image->shdr;
|
||||
const Elf_Shdr *shdr_end = shdr + image->shnum;
|
||||
size_t namelen = strlen(name);
|
||||
|
||||
while (shdr < shdr_end) {
|
||||
if (shdr->sh_name + namelen >= image->shstrtab_size) {
|
||||
set_errmsg("too big section header string table index: %u", shdr->sh_name);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
if (strcmp(image->shstrtab + shdr->sh_name, name) == 0) {
|
||||
*out = shdr;
|
||||
return 0;
|
||||
}
|
||||
shdr++;
|
||||
}
|
||||
set_errmsg("failed to find the section header: %s", name);
|
||||
return PLTHOOK_INVALID_FILE_FORMAT;
|
||||
}
|
||||
|
||||
static void set_errmsg(const char *fmt, ...)
|
||||
{
|
||||
va_list ap;
|
||||
va_start(ap, fmt);
|
||||
vsnprintf(errmsg, sizeof(errmsg) - 1, fmt, ap);
|
||||
va_end(ap);
|
||||
}
|
||||
Reference in New Issue
Block a user