/* * 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 #include #include #include #ifdef HAVE_SYS_MMAN_H #include #endif #ifdef HAVE_UNISTD_H # include #endif #ifndef PATH_MAX #define PATH_MAX MAX_PATH #endif #include "debugger.h" #if defined(__svr4__) || defined(__sun) #define __ELF__ #endif #ifdef HAVE_ELF_H # include #endif #ifdef HAVE_SYS_ELF32_H # include #endif #ifdef HAVE_SYS_EXEC_ELF_H # include #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 #endif #ifdef HAVE_SYS_LINK_H # include #endif #include "wine/debug.h" WINE_DEFAULT_DEBUG_CHANNEL(winedbg); typedef struct tagELF_DBG_INFO { void *elf_addr; } ELF_DBG_INFO; #ifdef __ELF__ /* * 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 DEBUG_ProcessElfSymtab(DBG_MODULE* module, const char* addr, void *load_addr, const Elf32_Shdr* symtab, const Elf32_Shdr* strtab) { const char* curfile = NULL; struct name_hash* curr_sym = NULL; int flags; int i; DBG_VALUE new_value; int nsym; const char* strp; const char* symname; const Elf32_Sym* symp; 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; /* * Save the name of the current file, so we have a way of tracking * static functions/data. */ if (ELF32_ST_TYPE(symp->st_info) == STT_FILE) { curfile = symname; continue; } new_value.type = NULL; new_value.addr.seg = 0; new_value.addr.off = (unsigned long)load_addr + symp->st_value; new_value.cookie = DV_TARGET; flags = SYM_WINE | ((ELF32_ST_TYPE(symp->st_info) == STT_FUNC) ? SYM_FUNC : SYM_DATA); if (ELF32_ST_BIND(symp->st_info) == STB_GLOBAL) curr_sym = DEBUG_AddSymbol(symname, &new_value, NULL, flags); else curr_sym = DEBUG_AddSymbol(symname, &new_value, curfile, flags); /* * Record the size of the symbol. This can come in handy in * some cases. Not really used yet, however. */ if (symp->st_size != 0) DEBUG_SetSymbolSize(curr_sym, symp->st_size); } return TRUE; } /* * 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 */ enum DbgInfoLoad DEBUG_LoadElfStabs(DBG_MODULE* module) { enum DbgInfoLoad dil = DIL_ERROR; 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; if (module->type != DMT_ELF || !module->elf_dbg_info) { WINE_ERR("Bad elf module '%s'\n", module->module_name); return DIL_ERROR; } /* check that the file exists, and that the module hasn't been loaded yet */ if (stat(module->module_name, &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_name, O_RDONLY)) == -1) goto leave; dil = DIL_NOINFO; /* * Now mmap() the file. */ addr = mmap(0, statbuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0); if (addr == (char*)0xffffffff) goto leave; /* * 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); 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 (stabsect != -1 && stabstrsect != -1) { /* * OK, now just parse all of the stabs. */ if (DEBUG_ParseStabs(addr, module->elf_dbg_info->elf_addr, spnt[stabsect].sh_offset, spnt[stabsect].sh_size, spnt[stabstrsect].sh_offset, spnt[stabstrsect].sh_size)) { dil = DIL_LOADED; } else { dil = DIL_ERROR; WINE_WARN("Couldn't read correctly read stabs\n"); goto leave; } } else if (debugsect != -1) { /* Dwarf 2 debug information */ dil = DIL_NOT_SUPPORTED; } /* now load dynamic symbol info */ for (i = 0; i < ehptr->e_shnum; i++) { if ((strcmp(shstrtab + spnt[i].sh_name, ".symtab") == 0) && (spnt[i].sh_type == SHT_SYMTAB)) DEBUG_ProcessElfSymtab(module, addr, module->elf_dbg_info->elf_addr, spnt + i, spnt + spnt[i].sh_link); if ((strcmp(shstrtab + spnt[i].sh_name, ".dynsym") == 0) && (spnt[i].sh_type == SHT_DYNSYM)) DEBUG_ProcessElfSymtab(module, addr, module->elf_dbg_info->elf_addr, spnt + i, spnt + spnt[i].sh_link); } leave: if (addr != (char*)0xffffffff) munmap(addr, statbuf.st_size); if (fd != -1) close(fd); return dil; } 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 ; } /* * 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 enum DbgInfoLoad DEBUG_ProcessElfFile(HANDLE hProcess, const char* filename, void *load_offset, struct elf_info* elf_info) { static const unsigned char elf_signature[4] = { ELFMAG0, ELFMAG1, ELFMAG2, ELFMAG3 }; enum DbgInfoLoad dil = DIL_ERROR; 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; WINE_TRACE("Processing elf file '%s' at %p\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; dil = DIL_NOINFO; /* * 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); elf_info->size = 0; for (i = 0; i < ehptr->e_phnum; i++) { if (ppnt[i].p_type != PT_LOAD) continue; elf_info->size += (ppnt[i].p_align <= 1) ? ppnt[i].p_memsz : (ppnt[i].p_memsz + ppnt[i].p_align - 1) & ~(ppnt[i].p_align - 1); } for (i = 0; i < ehptr->e_shnum; i++) { if (strcmp(shstrtab + spnt[i].sh_name, ".dynamic") == 0 && spnt[i].sh_type == SHT_DYNAMIC) { if (elf_info->flags & ELF_INFO_DEBUG_HEADER) { Elf32_Dyn dyn; char* ptr = (char*)spnt[i].sh_addr; unsigned long len; do { if (!ReadProcessMemory(hProcess, 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) { dil = DIL_ERROR; goto leave; } elf_info->dbg_hdr_addr = dyn.d_un.d_ptr; } } } elf_info->segments[0] = elf_info->segments[1] = elf_info->segments[2] = 0; if (elf_info->flags & ELF_INFO_PATH) { strncpy(elf_info->elf_path, filename, elf_info->elf_path_len); elf_info->elf_path[elf_info->elf_path_len - 1] = '\0'; } elf_info->load_addr = (load_offset == 0) ? (void *)ehptr->e_entry : load_offset; if (elf_info->flags & ELF_INFO_MODULE) { DBG_MODULE* module; module = DEBUG_AddModule(filename, DMT_ELF, elf_info->load_addr, elf_info->size, 0); if (module) { if ((module->elf_dbg_info = DBG_alloc(sizeof(ELF_DBG_INFO))) == NULL) { WINE_ERR("OOM\n"); exit(0); } module->elf_dbg_info->elf_addr = load_offset; module->dil = dil = DEBUG_LoadElfStabs(module); } else dil = DIL_ERROR; } leave: if (addr != (char*)0xffffffff) munmap((void*)addr, statbuf.st_size); if (fd != -1) close(fd); return dil; } static enum DbgInfoLoad DEBUG_ProcessElfFileFromPath(HANDLE hProcess, const char * filename, void *load_offset, const char* path, struct elf_info* elf_info) { enum DbgInfoLoad dil = DIL_ERROR; char *s, *t, *fn; char* paths = NULL; if (!path) return dil; for (s = paths = DBG_strdup(path); s && *s; s = (t) ? (t+1) : NULL) { t = strchr(s, ':'); if (t) *t = '\0'; fn = (char*)DBG_alloc(strlen(filename) + 1 + strlen(s) + 1); if (!fn) break; strcpy(fn, s ); strcat(fn, "/"); strcat(fn, filename); dil = DEBUG_ProcessElfFile(hProcess, fn, load_offset, elf_info); DBG_free(fn); if (dil != DIL_ERROR) break; s = (t) ? (t+1) : NULL; } DBG_free(paths); return dil; } static enum DbgInfoLoad DEBUG_ProcessElfObject(HANDLE hProcess, const char* filename, void *load_offset, struct elf_info* elf_info) { enum DbgInfoLoad dil = DIL_ERROR; if (filename == NULL || *filename == '\0') return DIL_ERROR; if (DEBUG_FindModuleByName(filename, DMT_ELF)) { assert(!(elf_info->flags & ELF_INFO_PATH)); return DIL_LOADED; } if (strstr(filename, "libstdc++")) return DIL_ERROR; /* We know we can't do it */ dil = DEBUG_ProcessElfFile(hProcess, filename, load_offset, elf_info); /* if relative pathname, try some absolute base dirs */ if (dil == DIL_ERROR && !strchr(filename, '/')) { dil = DEBUG_ProcessElfFileFromPath(hProcess, filename, load_offset, getenv("PATH"), elf_info); if (dil == DIL_ERROR) dil = DEBUG_ProcessElfFileFromPath(hProcess, filename, load_offset, getenv("LD_LIBRARY_PATH"), elf_info); if (dil == DIL_ERROR) dil = DEBUG_ProcessElfFileFromPath(hProcess, filename, load_offset, getenv("WINEDLLPATH"), elf_info); } DEBUG_ReportDIL(dil, "ELF", filename, load_offset); return dil; } static BOOL DEBUG_WalkList(const struct r_debug* dbg_hdr) { void* lm_addr; struct link_map lm; char bufstr[256]; struct elf_info elf_info; 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 (!DEBUG_READ_MEM_VERBOSE(lm_addr, &lm, sizeof(lm))) return FALSE; if (lm.l_prev != NULL && /* skip first entry, normally debuggee itself */ lm.l_name != NULL && DEBUG_READ_MEM_VERBOSE((void*)lm.l_name, bufstr, sizeof(bufstr))) { bufstr[sizeof(bufstr) - 1] = '\0'; DEBUG_ProcessElfObject(DEBUG_CurrProcess->handle, bufstr, (void *)lm.l_addr, &elf_info); } } return TRUE; } static BOOL DEBUG_RescanElf(void) { struct r_debug dbg_hdr; if (DEBUG_CurrProcess && DEBUG_READ_MEM_VERBOSE((void*)DEBUG_CurrProcess->dbg_hdr_addr, &dbg_hdr, sizeof(dbg_hdr))) { switch (dbg_hdr.r_state) { case RT_CONSISTENT: DEBUG_WalkList(&dbg_hdr); DEBUG_CheckDelayedBP(); break; case RT_ADD: break; case RT_DELETE: /* FIXME: this is not currently handled */ break; } } return FALSE; } /****************************************************************** * DEBUG_ReadWineLoaderDbgInfo * * Try to find a decent wine executable which could have loader the debuggee */ enum DbgInfoLoad DEBUG_ReadWineLoaderDbgInfo(HANDLE hProcess, struct elf_info* elf_info) { const char* ptr; enum DbgInfoLoad dil; /* All binaries are loaded with WINELOADER (if run from tree) or by the * main executable (either wine-kthread or wine-pthread) * Note: the heuristic used to know whether we need to load wine-pthread or * wine-kthread is not 100% safe */ elf_info->flags |= ELF_INFO_DEBUG_HEADER; if ((ptr = getenv("WINELOADER"))) dil = DEBUG_ProcessElfObject(hProcess, ptr, 0, elf_info); else { if ((dil = DEBUG_ProcessElfObject(hProcess, "wine-kthread", 0, elf_info)) == DIL_ERROR) dil = DEBUG_ProcessElfObject(hProcess, "wine-pthread", 0, elf_info); } return dil; } /****************************************************************** * DEBUG_SetElfSoLoadBreakpoint * * Sets a breakpoint to handle .so loading events, so we can add debug info * on the fly */ BOOL DEBUG_SetElfSoLoadBreakpoint(const struct elf_info* elf_info) { struct r_debug dbg_hdr; /* * OK, now dig into the actual tables themselves. */ if (!DEBUG_READ_MEM_VERBOSE((void*)elf_info->dbg_hdr_addr, &dbg_hdr, sizeof(dbg_hdr))) return FALSE; assert(!DEBUG_CurrProcess->dbg_hdr_addr); DEBUG_CurrProcess->dbg_hdr_addr = elf_info->dbg_hdr_addr; if (dbg_hdr.r_brk) { DBG_VALUE value; WINE_TRACE("Setting up a breakpoint on r_brk(%lx)\n", (unsigned long)dbg_hdr.r_brk); DEBUG_SetBreakpoints(FALSE); value.type = NULL; value.cookie = DV_TARGET; value.addr.seg = 0; value.addr.off = (DWORD)dbg_hdr.r_brk; DEBUG_AddBreakpoint(&value, DEBUG_RescanElf, TRUE); DEBUG_SetBreakpoints(TRUE); } return DEBUG_WalkList(&dbg_hdr); } #else /* !__ELF__ */ enum DbgInfoLoad DEBUG_ReadWineLoaderDbgInfo(HANDLE hProcess, struct elf_info* elf_info) { return DIL_ERROR; } BOOL DEBUG_SetElfSoLoadBreakpoint(const struct elf_info* elf_info) { return FALSE; } #endif /* __ELF__ */