Sweden-Number/dlls/dbghelp/elf_module.c

641 lines
20 KiB
C

/*
* File elf.c - processing of ELF files
*
* Copyright (C) 1996, Eric Youngdale.
* 1999-2004 Eric Pouech
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "config.h"
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifndef PATH_MAX
#define PATH_MAX MAX_PATH
#endif
#include "dbghelp_private.h"
#if defined(__svr4__) || defined(__sun)
#define __ELF__
#endif
#ifdef HAVE_ELF_H
# include <elf.h>
#endif
#ifdef HAVE_SYS_ELF32_H
# include <sys/elf32.h>
#endif
#ifdef HAVE_SYS_EXEC_ELF_H
# include <sys/exec_elf.h>
#endif
#if !defined(DT_NUM)
# if defined(DT_COUNT)
# define DT_NUM DT_COUNT
# else
/* this seems to be a satisfactory value on Solaris, which doesn't support this AFAICT */
# define DT_NUM 24
# endif
#endif
#ifdef HAVE_LINK_H
# include <link.h>
#endif
#ifdef HAVE_SYS_LINK_H
# include <sys/link.h>
#endif
#include "wine/debug.h"
WINE_DEFAULT_DEBUG_CHANNEL(dbghelp);
typedef struct tagELF_DBG_INFO
{
unsigned long elf_addr;
} ELF_DBG_INFO;
#ifdef __ELF__
#define ELF_INFO_DEBUG_HEADER 0x0001
#define ELF_INFO_MODULE 0x0002
struct elf_info
{
unsigned flags; /* IN one (or several) of the ELF_INFO constants */
unsigned long dbg_hdr_addr; /* OUT address of debug header (if ELF_INFO_DEBUG_HEADER is set) */
struct module* module; /* OUT loaded module (if ELF_INFO_MODULE is set) */
};
/******************************************************************
* elf_load_symtab
*
* Walk through the entire symbol table and add any symbols we find there.
* This can be used in cases where we have stripped ELF shared libraries,
* or it can be used in cases where we have data symbols for which the address
* isn't encoded in the stabs.
*
* This is all really quite easy, since we don't have to worry about line
* numbers or local data variables.
*/
static int elf_load_symtab(struct module* module, const char* addr,
unsigned long load_addr, const Elf32_Shdr* symtab,
const Elf32_Shdr* strtab)
{
int i, nsym;
const char* strp;
const char* symname;
const Elf32_Sym* symp;
struct symt_compiland* compiland = NULL;
symp = (Elf32_Sym*)(addr + symtab->sh_offset);
nsym = symtab->sh_size / sizeof(*symp);
strp = (char*)(addr + strtab->sh_offset);
for (i = 0; i < nsym; i++, symp++)
{
/* Ignore certain types of entries which really aren't of that much
* interest.
*/
if (ELF32_ST_TYPE(symp->st_info) == STT_SECTION ||
symp->st_shndx == SHN_UNDEF)
{
continue;
}
symname = strp + symp->st_name;
if (ELF32_ST_TYPE(symp->st_info) == STT_FILE)
{
compiland = symt_new_compiland(module, symname);
continue;
}
symt_new_public(module, compiland, symname,
load_addr + symp->st_value, symp->st_size,
TRUE /* FIXME */, ELF32_ST_TYPE(symp->st_info) == STT_FUNC);
}
return TRUE;
}
/******************************************************************
* elf_load_debug_info
*
* Loads the symbolic information from ELF module stored in 'filename'
* the module has been loaded at 'load_offset' address, so symbols' address
* relocation is performed
* returns
* -1 if the file cannot be found/opened
* 0 if the file doesn't contain symbolic info (or this info cannot be
* read or parsed)
* 1 on success
*/
SYM_TYPE elf_load_debug_info(struct module* module)
{
SYM_TYPE sym_type = -1;
char* addr = (char*)0xffffffff;
int fd = -1;
struct stat statbuf;
const Elf32_Ehdr* ehptr;
const Elf32_Shdr* spnt;
const char* shstrtab;
int i;
int stabsect, stabstrsect, debugsect;
int symsect, dynsect;
if (module->type != DMT_ELF || !module->elf_dbg_info)
{
ERR("Bad elf module '%s'\n", module->module.LoadedImageName);
return sym_type;
}
TRACE("%s\n", module->module.LoadedImageName);
/* check that the file exists, and that the module hasn't been loaded yet */
if (stat(module->module.LoadedImageName, &statbuf) == -1) goto leave;
if (S_ISDIR(statbuf.st_mode)) goto leave;
/*
* Now open the file, so that we can mmap() it.
*/
if ((fd = open(module->module.LoadedImageName, O_RDONLY)) == -1) goto leave;
/*
* Now mmap() the file.
*/
addr = mmap(0, statbuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
if (addr == (char*)0xffffffff) goto leave;
sym_type = SymNone;
/*
* Next, we need to find a few of the internal ELF headers within
* this thing. We need the main executable header, and the section
* table.
*/
ehptr = (Elf32_Ehdr*)addr;
spnt = (Elf32_Shdr*)(addr + ehptr->e_shoff);
shstrtab = (addr + spnt[ehptr->e_shstrndx].sh_offset);
symsect = dynsect = stabsect = stabstrsect = debugsect = -1;
for (i = 0; i < ehptr->e_shnum; i++)
{
if (strcmp(shstrtab + spnt[i].sh_name, ".stab") == 0)
stabsect = i;
if (strcmp(shstrtab + spnt[i].sh_name, ".stabstr") == 0)
stabstrsect = i;
if (strcmp(shstrtab + spnt[i].sh_name, ".debug_info") == 0)
debugsect = i;
if ((strcmp(shstrtab + spnt[i].sh_name, ".symtab") == 0) &&
(spnt[i].sh_type == SHT_SYMTAB))
symsect = i;
if ((strcmp(shstrtab + spnt[i].sh_name, ".dynsym") == 0) &&
(spnt[i].sh_type == SHT_DYNSYM))
dynsect = i;
}
/* start loading dynamic symbol info (so that we can get the correct address) */
if (symsect != -1)
elf_load_symtab(module, addr, module->elf_dbg_info->elf_addr,
spnt + symsect, spnt + spnt[symsect].sh_link);
else if (dynsect != -1)
elf_load_symtab(module, addr, module->elf_dbg_info->elf_addr,
spnt + dynsect, spnt + spnt[dynsect].sh_link);
sym_type = SymExport;
if (!(dbghelp_options & SYMOPT_PUBLICS_ONLY))
{
if (stabsect != -1 && stabstrsect != -1)
{
/* OK, now just parse all of the stabs. */
sym_type = stabs_parse(module, addr, module->elf_dbg_info->elf_addr,
spnt[stabsect].sh_offset, spnt[stabsect].sh_size,
spnt[stabstrsect].sh_offset,
spnt[stabstrsect].sh_size);
if (sym_type == -1)
{
WARN("Couldn't read correctly read stabs\n");
goto leave;
}
}
else if (debugsect != -1)
{
/* Dwarf 2 debug information */
FIXME("Unsupported Dwarf2 information\n");
sym_type = SymNone;
}
}
leave:
if (addr != (char*)0xffffffff) munmap(addr, statbuf.st_size);
if (fd != -1) close(fd);
return module->module.SymType = sym_type;
}
/******************************************************************
* is_dt_flag_valid
* returns true iff the section tag is valid
*/
static unsigned is_dt_flag_valid(unsigned d_tag)
{
#ifndef DT_PROCNUM
#define DT_PROCNUM 0
#endif
#ifndef DT_EXTRANUM
#define DT_EXTRANUM 0
#endif
return (d_tag >= 0 && d_tag < DT_NUM + DT_PROCNUM + DT_EXTRANUM)
#if defined(DT_LOOS) && defined(DT_HIOS)
|| (d_tag >= DT_LOOS && d_tag < DT_HIOS)
#endif
#if defined(DT_LOPROC) && defined(DT_HIPROC)
|| (d_tag >= DT_LOPROC && d_tag < DT_HIPROC)
#endif
;
}
/******************************************************************
* elf_load_file
*
* Loads the information for ELF module stored in 'filename'
* the module has been loaded at 'load_offset' address
* returns
* -1 if the file cannot be found/opened
* 0 if the file doesn't contain symbolic info (or this info cannot be
* read or parsed)
* 1 on success
*/
static SYM_TYPE elf_load_file(struct process* pcs, const char* filename,
unsigned long load_offset, struct elf_info* elf_info)
{
static const BYTE elf_signature[4] = { ELFMAG0, ELFMAG1, ELFMAG2, ELFMAG3 };
SYM_TYPE sym_type = -1;
const char* addr = (char*)0xffffffff;
int fd = -1;
struct stat statbuf;
const Elf32_Ehdr* ehptr;
const Elf32_Shdr* spnt;
const Elf32_Phdr* ppnt;
const char* shstrtab;
int i;
DWORD delta, size;
TRACE("Processing elf file '%s' at %08lx\n", filename, load_offset);
/* check that the file exists, and that the module hasn't been loaded yet */
if (stat(filename, &statbuf) == -1) goto leave;
/* Now open the file, so that we can mmap() it. */
if ((fd = open(filename, O_RDONLY)) == -1) goto leave;
/* Now mmap() the file. */
addr = mmap(0, statbuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
if (addr == (char*)-1) goto leave;
sym_type = SymNone;
/* Next, we need to find a few of the internal ELF headers within
* this thing. We need the main executable header, and the section
* table.
*/
ehptr = (Elf32_Ehdr*)addr;
if (memcmp(ehptr->e_ident, elf_signature, sizeof(elf_signature))) goto leave;
spnt = (Elf32_Shdr*)(addr + ehptr->e_shoff);
shstrtab = (addr + spnt[ehptr->e_shstrndx].sh_offset);
/* if non relocatable ELF, then remove fixed address from computation
* otherwise, all addresses are zero based
*/
delta = (load_offset == 0) ? ehptr->e_entry : 0;
/* grab size of module once loaded in memory */
ppnt = (Elf32_Phdr*)(addr + ehptr->e_phoff);
size = 0;
for (i = 0; i < ehptr->e_phnum; i++)
{
if (ppnt[i].p_type == PT_LOAD)
{
size += (ppnt[i].p_align <= 1) ? ppnt[i].p_memsz :
(ppnt[i].p_memsz + ppnt[i].p_align - 1) & ~(ppnt[i].p_align - 1);
}
}
if (elf_info->flags & ELF_INFO_DEBUG_HEADER)
{
for (i = 0; i < ehptr->e_shnum; i++)
{
if (strcmp(shstrtab + spnt[i].sh_name, ".dynamic") == 0 &&
spnt[i].sh_type == SHT_DYNAMIC)
{
Elf32_Dyn dyn;
char* ptr = (char*)spnt[i].sh_addr;
unsigned long len;
do
{
if (!ReadProcessMemory(pcs->handle, ptr, &dyn, sizeof(dyn), &len) ||
len != sizeof(dyn) || !is_dt_flag_valid(dyn.d_tag))
dyn.d_tag = DT_NULL;
ptr += sizeof(dyn);
} while (dyn.d_tag != DT_DEBUG && dyn.d_tag != DT_NULL);
if (dyn.d_tag == DT_NULL)
{
sym_type = -1;
goto leave;
}
elf_info->dbg_hdr_addr = dyn.d_un.d_ptr;
}
}
}
if (elf_info->flags & ELF_INFO_MODULE)
{
elf_info->module = module_new(pcs, filename, DMT_ELF,
(load_offset) ? load_offset : ehptr->e_entry,
size, 0, 0);
if (elf_info->module)
{
if ((elf_info->module->elf_dbg_info = HeapAlloc(GetProcessHeap(), 0, sizeof(ELF_DBG_INFO))) == NULL)
{
ERR("OOM\n");
exit(0); /* FIXME */
}
elf_info->module->elf_dbg_info->elf_addr = load_offset;
elf_info->module->module.SymType = sym_type =
(dbghelp_options & SYMOPT_DEFERRED_LOADS) ? SymDeferred :
elf_load_debug_info(elf_info->module);
elf_info->module->elf_mark = 1;
}
else sym_type = -1;
}
leave:
if (addr != (char*)0xffffffff) munmap((void*)addr, statbuf.st_size);
if (fd != -1) close(fd);
return sym_type;
}
/******************************************************************
* elf_load_file_from_path
* tries to load an ELF file from a set of paths (separated by ':')
*/
static SYM_TYPE elf_load_file_from_path(HANDLE hProcess,
const char* filename,
unsigned long load_offset,
const char* path,
struct elf_info* elf_info)
{
SYM_TYPE sym_type = -1;
char *s, *t, *fn;
char* paths = NULL;
if (!path) return sym_type;
paths = strcpy(HeapAlloc(GetProcessHeap(), 0, strlen(path) + 1), path);
for (s = paths; s && *s; s = (t) ? (t+1) : NULL)
{
t = strchr(s, ':');
if (t) *t = '\0';
fn = HeapAlloc(GetProcessHeap(), 0, strlen(filename) + 1 + strlen(s) + 1);
if (!fn) break;
strcpy(fn, s);
strcat(fn, "/");
strcat(fn, filename);
sym_type = elf_load_file(hProcess, fn, load_offset, elf_info);
HeapFree(GetProcessHeap(), 0, fn);
if (sym_type != -1) break;
s = (t) ? (t+1) : NULL;
}
HeapFree(GetProcessHeap(), 0, paths);
return sym_type;
}
/******************************************************************
* elf_search_and_load_file
*
* lookup a file in standard ELF locations, and if found, load it
*/
static SYM_TYPE elf_search_and_load_file(struct process* pcs, const char* filename,
unsigned long load_offset, struct elf_info* elf_info)
{
SYM_TYPE sym_type = -1;
struct module* module;
if (filename == NULL || *filename == '\0') return sym_type;
if ((module = module_find_by_name(pcs, filename, DMT_ELF)))
{
elf_info->module = module;
module->elf_mark = 1;
return module->module.SymType;
}
if (strstr(filename, "libstdc++")) return -1; /* We know we can't do it */
sym_type = elf_load_file(pcs, filename, load_offset, elf_info);
/* if relative pathname, try some absolute base dirs */
if (sym_type == -1 && !strchr(filename, '/'))
{
sym_type = elf_load_file_from_path(pcs, filename, load_offset,
getenv("PATH"), elf_info);
if (sym_type == -1)
sym_type = elf_load_file_from_path(pcs, filename, load_offset,
getenv("LD_LIBRARY_PATH"), elf_info);
if (sym_type == -1)
sym_type = elf_load_file_from_path(pcs, filename, load_offset,
getenv("WINEDLLPATH"), elf_info);
}
return sym_type;
}
/******************************************************************
* elf_synchronize_module_list
*
* this functions rescans the debuggee module's list and synchronizes it with
* the one from 'pcs', ie:
* - if a module is in debuggee and not in pcs, it's loaded into pcs
* - if a module is in pcs and not in debuggee, it's unloaded from pcs
*/
BOOL elf_synchronize_module_list(struct process* pcs)
{
struct r_debug dbg_hdr;
void* lm_addr;
struct link_map lm;
char bufstr[256];
struct elf_info elf_info;
struct module* module;
if (!pcs->dbg_hdr_addr) return FALSE;
if (!read_mem(pcs->handle, pcs->dbg_hdr_addr, &dbg_hdr, sizeof(dbg_hdr)) ||
dbg_hdr.r_state != RT_CONSISTENT)
return FALSE;
for (module = pcs->lmodules; module; module = module->next)
{
if (module->type == DMT_ELF) module->elf_mark = 0;
}
elf_info.flags = ELF_INFO_MODULE;
/* Now walk the linked list. In all known ELF implementations,
* the dynamic loader maintains this linked list for us. In some
* cases the first entry doesn't appear with a name, in other cases it
* does.
*/
for (lm_addr = (void*)dbg_hdr.r_map; lm_addr; lm_addr = (void*)lm.l_next)
{
if (!read_mem(pcs->handle, (ULONG)lm_addr, &lm, sizeof(lm)))
return FALSE;
if (lm.l_prev != NULL && /* skip first entry, normally debuggee itself */
lm.l_name != NULL &&
read_mem(pcs->handle, (ULONG)lm.l_name, bufstr, sizeof(bufstr)))
{
bufstr[sizeof(bufstr) - 1] = '\0';
elf_search_and_load_file(pcs, bufstr, (unsigned long)lm.l_addr,
&elf_info);
}
}
for (module = pcs->lmodules; module; module = module->next)
{
if (module->type == DMT_ELF && !module->elf_mark)
{
module_remove(pcs, module);
/* restart all over */
module = pcs->lmodules;
}
}
return TRUE;
}
/******************************************************************
* elf_read_wine_loader_dbg_info
*
* Try to find a decent wine executable which could have loader the debuggee
*/
unsigned long elf_read_wine_loader_dbg_info(struct process* pcs)
{
const char* ptr;
SYM_TYPE sym_type;
struct elf_info elf_info;
elf_info.flags = ELF_INFO_DEBUG_HEADER;
/* All binaries are loaded with WINELOADER (if run from tree) or by the
* main executable (either wine-kthread or wine-pthread)
* Note: the heuristic use to know whether we need to load wine-pthread or
* wine-kthread is not 100% safe
*/
if ((ptr = getenv("WINELOADER")))
sym_type = elf_search_and_load_file(pcs, ptr, 0, &elf_info);
else
{
if ((sym_type = elf_search_and_load_file(pcs, "wine-kthread", 0, &elf_info)) == -1)
sym_type = elf_search_and_load_file(pcs, "wine-pthread", 0, &elf_info);
}
return (sym_type < 0) ? 0 : elf_info.dbg_hdr_addr;
}
/******************************************************************
* elf_load_module
*
* loads an ELF module and stores it in process' module list
* if 'sync' is TRUE, let's find module real name and load address from
* the real loaded modules list in pcs address space
*/
struct module* elf_load_module(struct process* pcs, const char* name)
{
struct elf_info elf_info;
SYM_TYPE sym_type = -1;
const char* p;
const char* xname;
struct r_debug dbg_hdr;
void* lm_addr;
struct link_map lm;
char bufstr[256];
TRACE("(%p %s)\n", pcs, name);
elf_info.flags = ELF_INFO_MODULE;
/* do only the lookup from the filename, not the path (as we lookup module name
* in the process' loaded module list)
*/
xname = strrchr(name, '/');
if (!xname++) xname = name;
if (!read_mem(pcs->handle, pcs->dbg_hdr_addr, &dbg_hdr, sizeof(dbg_hdr)) ||
dbg_hdr.r_state != RT_CONSISTENT)
return NULL;
for (lm_addr = (void*)dbg_hdr.r_map; lm_addr; lm_addr = (void*)lm.l_next)
{
if (!read_mem(pcs->handle, (ULONG)lm_addr, &lm, sizeof(lm)))
return NULL;
if (lm.l_prev != NULL && /* skip first entry, normally debuggee itself */
lm.l_name != NULL &&
read_mem(pcs->handle, (ULONG)lm.l_name, bufstr, sizeof(bufstr)))
{
bufstr[sizeof(bufstr) - 1] = '\0';
/* memcmp is needed for matches when bufstr contains also version information
* name: libc.so, bufstr: libc.so.6.0
*/
p = strrchr(bufstr, '/');
if (!p++) p = bufstr;
if (!memcmp(p, xname, strlen(xname)))
{
sym_type = elf_search_and_load_file(pcs, bufstr,
(unsigned long)lm.l_addr, &elf_info);
break;
}
}
}
if (!lm_addr || sym_type == -1) return NULL;
assert(elf_info.module);
return elf_info.module;
}
#else /* !__ELF__ */
BOOL elf_synchronize_module_list(struct process* pcs)
{
return FALSE;
}
unsigned long elf_read_wine_loader_dbg_info(struct process* pcs)
{
return -1;
}
struct module* elf_load_module(struct process* pcs, const char* name)
{
return NULL;
}
SYM_TYPE elf_load_debug_info(struct module* module)
{
return -1;
}
#endif /* __ELF__ */