diff options
Diffstat (limited to 'ldso/util/ldd.c')
| -rw-r--r-- | ldso/util/ldd.c | 664 |
1 files changed, 0 insertions, 664 deletions
diff --git a/ldso/util/ldd.c b/ldso/util/ldd.c deleted file mode 100644 index 3ea41b424..000000000 --- a/ldso/util/ldd.c +++ /dev/null @@ -1,664 +0,0 @@ -/* vi: set sw=4 ts=4: */ -/* - * A small little ldd implementation for uClibc - * - * Copyright (C) 2000 by Lineo, inc and Erik Andersen - * Copyright (C) 2000-2002 Erik Andersen <andersee@debian.org> - * - * Several functions in this file (specifically, elf_find_section_type(), - * elf_find_phdr_type(), and elf_find_dynamic(), were stolen from elflib.c from - * elfvector (http://www.BitWagon.com/elfvector.html) by John F. Reiser - * <jreiser@BitWagon.com>, which is copyright 2000 BitWagon Software LLC - * (GPL2). - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program 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 - * General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - * - */ - - -#define _GNU_SOURCE -#include <stdlib.h> -#include <stdio.h> -#include <fcntl.h> -#include <string.h> -#include <unistd.h> -#include <sys/mman.h> -#include <sys/stat.h> -#include <sys/types.h> -#include <sys/types.h> -#include <sys/wait.h> - -#include "bswap.h" -#if defined (sun) -#include "link.h" -#else -#include "elf.h" -#endif - -#ifdef DMALLOC -#include <dmalloc.h> -#endif - -#if defined(__arm__) -#define MATCH_MACHINE(x) (x == EM_ARM) -#define ELFCLASSM ELFCLASS32 -#endif - -#if defined(__s390__) -#define MATCH_MACHINE(x) (x == EM_S390) -#define ELFCLASSM ELFCLASS32 -#endif - -#if defined(__i386__) -#ifndef EM_486 -#define MATCH_MACHINE(x) (x == EM_386) -#else -#define MATCH_MACHINE(x) (x == EM_386 || x == EM_486) -#endif -#define ELFCLASSM ELFCLASS32 -#endif - -#if defined(__mc68000__) -#define MATCH_MACHINE(x) (x == EM_68K) -#define ELFCLASSM ELFCLASS32 -#endif - -#if defined(__mips__) -#define MATCH_MACHINE(x) (x == EM_MIPS || x == EM_MIPS_RS3_LE) -#define ELFCLASSM ELFCLASS32 -#endif - -#if defined(__powerpc__) -#define MATCH_MACHINE(x) (x == EM_PPC) -#define ELFCLASSM ELFCLASS32 -#endif - -#if defined(__sh__) -#define MATCH_MACHINE(x) (x == EM_SH) -#define ELFCLASSM ELFCLASS32 -#endif - -#if defined (__v850e__) -#define MATCH_MACHINE(x) ((x) == EM_V850 || (x) == EM_CYGNUS_V850) -#define ELFCLASSM ELFCLASS32 -#endif - -#if defined (__sparc__) -#define MATCH_MACHINE(x) ((x) == EM_SPARC || (x) == EM_SPARC32PLUS) -#define ELFCLASSM ELFCLASS32 -#endif - - -#ifndef MATCH_MACHINE -#warning "You really should add a MATCH_MACHINE() macro for your architecture" -#endif - -#if __BYTE_ORDER == __LITTLE_ENDIAN -#define ELFDATAM ELFDATA2LSB -#elif __BYTE_ORDER == __BIG_ENDIAN -#define ELFDATAM ELFDATA2MSB -#endif - -struct library { - char *name; - int resolved; - char *path; - struct library *next; -}; -struct library *lib_list = NULL; -char not_found[] = "not found"; -char *interp = NULL; -char *interp_dir = NULL; -int byteswap; -static int interpreter_already_found=0; - -inline uint32_t byteswap32_to_host(uint32_t value) -{ - if (byteswap==1) { - return(bswap_32(value)); - } else { - return(value); - } -} - - - -Elf32_Shdr * elf_find_section_type( int key, Elf32_Ehdr *ehdr) -{ - int j; - Elf32_Shdr *shdr; - shdr = (Elf32_Shdr *)(ehdr->e_shoff + (char *)ehdr); - for (j = ehdr->e_shnum; --j>=0; ++shdr) { - if (key==(int)byteswap32_to_host(shdr->sh_type)) { - return shdr; - } - } - return NULL; -} - -Elf32_Phdr * elf_find_phdr_type( int type, Elf32_Ehdr *ehdr) -{ - int j; - Elf32_Phdr *phdr = (Elf32_Phdr *)(ehdr->e_phoff + (char *)ehdr); - for (j = ehdr->e_phnum; --j>=0; ++phdr) { - if (type==(int)byteswap32_to_host(phdr->p_type)) { - return phdr; - } - } - return NULL; -} - -/* Returns value if return_val==1, ptr otherwise */ -void * elf_find_dynamic(int const key, Elf32_Dyn *dynp, - Elf32_Ehdr *ehdr, int return_val) -{ - Elf32_Phdr *pt_text = elf_find_phdr_type(PT_LOAD, ehdr); - unsigned tx_reloc = byteswap32_to_host(pt_text->p_vaddr) - byteswap32_to_host(pt_text->p_offset); - for (; DT_NULL!=byteswap32_to_host(dynp->d_tag); ++dynp) { - if (key == (int)byteswap32_to_host(dynp->d_tag)) { - if (return_val == 1) - return (void *)(intptr_t)byteswap32_to_host(dynp->d_un.d_val); - else - return (void *)(byteswap32_to_host(dynp->d_un.d_val) - tx_reloc + (char *)ehdr ); - } - } - return NULL; -} - -int check_elf_header(Elf32_Ehdr *const ehdr) -{ - if (! ehdr || strncmp((void *)ehdr, ELFMAG, SELFMAG) != 0 || - ehdr->e_ident[EI_CLASS] != ELFCLASS32 || - ehdr->e_ident[EI_VERSION] != EV_CURRENT) - { - return 1; - } - - /* Check if the target endianness matches the host's endianness */ - byteswap = 0; -#if __BYTE_ORDER == __LITTLE_ENDIAN - if (ehdr->e_ident[5] == ELFDATA2MSB) { - /* Ick -- we will have to byte-swap everything */ - byteswap = 1; - } -#elif __BYTE_ORDER == __BIG_ENDIAN - if (ehdr->e_ident[5] == ELFDATA2LSB) { - /* Ick -- we will have to byte-swap everything */ - byteswap = 1; - } -#else -#error Unknown host byte order! -#endif - - /* Be vary lazy, and only byteswap the stuff we use */ - if (byteswap==1) { - ehdr->e_type=bswap_16(ehdr->e_type); - ehdr->e_phoff=bswap_32(ehdr->e_phoff); - ehdr->e_shoff=bswap_32(ehdr->e_shoff); - ehdr->e_phnum=bswap_16(ehdr->e_phnum); - ehdr->e_shnum=bswap_16(ehdr->e_shnum); - } - - return 0; -} - -/* This function's behavior must exactly match that - * in uClibc/ldso/ldso/readelflib1.c */ -static void search_for_named_library(char *name, char *result, const char *path_list) -{ - int i, count = 1; - char *path, *path_n; - struct stat filestat; - - /* We need a writable copy of this string */ - path = strdup(path_list); - if (!path) { - fprintf(stderr, "Out of memory!\n"); - exit(EXIT_FAILURE); - } - /* Eliminate all double //s */ - path_n=path; - while((path_n=strstr(path_n, "//"))) { - i = strlen(path_n); - memmove(path_n, path_n+1, i-1); - *(path_n + i - 1)='\0'; - } - - /* Replace colons with zeros in path_list and count them */ - for(i=strlen(path); i > 0; i--) { - if (path[i]==':') { - path[i]=0; - count++; - } - } - path_n = path; - for (i = 0; i < count; i++) { - strcpy(result, path_n); - strcat(result, "/"); - strcat(result, name); - if (stat (result, &filestat) == 0 && filestat.st_mode & S_IRUSR) { - free(path); - return; - } - path_n += (strlen(path_n) + 1); - } - free(path); - *result = '\0'; -} - -void locate_library_file(Elf32_Ehdr* ehdr, Elf32_Dyn* dynamic, int is_suid, struct library *lib) -{ - char *buf; - char *path; - struct stat filestat; - - /* If this is a fully resolved name, our job is easy */ - if (stat (lib->name, &filestat) == 0) { - lib->path = lib->name; - return; - } - - /* We need some elbow room here. Make some room...*/ - buf = malloc(1024); - if (!buf) { - fprintf(stderr, "Out of memory!\n"); - exit(EXIT_FAILURE); - } - - /* This function must match the behavior of _dl_load_shared_library - * in readelflib1.c or things won't work out as expected... */ - - /* The ABI specifies that RPATH is searched first, so do that now. */ - path = (char *)elf_find_dynamic(DT_RPATH, dynamic, ehdr, 0); - if (path) { - search_for_named_library(lib->name, buf, path); - if (*buf != '\0') { - lib->path = buf; - return; - } - } - - /* Next check LD_{ELF_}LIBRARY_PATH if specified and allowed. - * Since this app doesn't actually run an executable I will skip - * the suid check, and just use LD_{ELF_}LIBRARY_PATH if set */ - if (is_suid==1) - path = NULL; - else - path = getenv("LD_LIBRARY_PATH"); - if (path) { - search_for_named_library(lib->name, buf, path); - if (*buf != '\0') { - lib->path = buf; - return; - } - } - -#ifdef USE_CACHE - /* FIXME -- add code to check the Cache here */ -#endif - - - /* Next look for libraries wherever the shared library - * loader was installed -- this is usually where we - * should find things... */ - if (interp_dir) { - search_for_named_library(lib->name, buf, interp_dir); - if (*buf != '\0') { - lib->path = buf; - return; - } - } - - /* Lastly, search the standard list of paths for the library. - This list must exactly match the list in uClibc/ldso/ldso/readelflib1.c */ - path = UCLIBC_RUNTIME_PREFIX "usr/X11R6/lib:" - UCLIBC_RUNTIME_PREFIX "usr/lib:" - UCLIBC_RUNTIME_PREFIX "lib:" - "/usr/lib:" - "/lib"; - search_for_named_library(lib->name, buf, path); - if (*buf != '\0') { - lib->path = buf; - } else { - free(buf); - lib->path = not_found; - } -} - -static int add_library(Elf32_Ehdr* ehdr, Elf32_Dyn* dynamic, int is_setuid, char *s) -{ - char *tmp, *tmp1, *tmp2; - struct library *cur, *newlib=lib_list; - - if (!s || !strlen(s)) - return 1; - - tmp = s; - while (*tmp) { - if (*tmp == '/') - s = tmp + 1; - tmp++; - } - - /* We add libc.so.0 elsewhere */ - if (interpreter_already_found && (tmp=strrchr(interp, '/')) != NULL) - { - int len = strlen(interp_dir); - if (strcmp(s, interp+1+len)==0) - return 1; - } - - for (cur = lib_list; cur; cur=cur->next) { - /* Check if this library is already in the list */ - tmp1 = tmp2 = cur->name; - while (*tmp1) { - if (*tmp1 == '/') - tmp2 = tmp1 + 1; - tmp1++; - } - if(strcmp(tmp2, s)==0) { - //printf("find_elf_interpreter is skipping '%s' (already in list)\n", cur->name); - return 0; - } - } - - /* Ok, this lib needs to be added to the list */ - newlib = malloc(sizeof(struct library)); - if (!newlib) - return 1; - newlib->name = malloc(strlen(s)+1); - strcpy(newlib->name, s); - newlib->resolved = 0; - newlib->path = NULL; - newlib->next = NULL; - - /* Now try and locate where this library might be living... */ - locate_library_file(ehdr, dynamic, is_setuid, newlib); - - //printf("add_library is adding '%s' to '%s'\n", newlib->name, newlib->path); - if (!lib_list) { - lib_list = newlib; - } else { - for (cur = lib_list; cur->next; cur=cur->next); /* nothing */ - cur->next = newlib; - } - return 0; -} - - -static void find_needed_libraries(Elf32_Ehdr* ehdr, Elf32_Dyn* dynamic, char *strtab, int is_setuid) -{ - Elf32_Dyn *dyns; - - for (dyns=dynamic; byteswap32_to_host(dyns->d_tag)!=DT_NULL; ++dyns) { - if (DT_NEEDED == byteswap32_to_host(dyns->d_tag)) { - add_library(ehdr, dynamic, is_setuid, - (char*)strtab + byteswap32_to_host(dyns->d_un.d_val)); - } - } -} - -static struct library * find_elf_interpreter(Elf32_Ehdr* ehdr) -{ - Elf32_Phdr *phdr; - - if (interpreter_already_found==1) - return NULL; - phdr = elf_find_phdr_type(PT_INTERP, ehdr); - if (phdr) { - struct library *cur, *newlib=NULL; - char *s = (char*)ehdr + byteswap32_to_host(phdr->p_offset); - - char *tmp, *tmp1; - interp = strdup(s); - interp_dir = strdup(s); - tmp = strrchr(interp_dir, '/'); - if (*tmp) - *tmp = '\0'; - else { - free(interp_dir); - interp_dir = interp; - } - tmp1 = tmp = s; - while (*tmp) { - if (*tmp == '/') - tmp1 = tmp + 1; - tmp++; - } - for (cur = lib_list; cur; cur=cur->next) { - /* Check if this library is already in the list */ - if(strcmp(cur->name, tmp1)==0) { - //printf("find_elf_interpreter is replacing '%s' (already in list)\n", cur->name); - newlib = cur; - free(newlib->name); - free(newlib->path); - return NULL; - } - } - if (newlib == NULL) - newlib = malloc(sizeof(struct library)); - if (!newlib) - return NULL; - newlib->name = malloc(strlen(s)+1); - strcpy(newlib->name, s); - newlib->path = newlib->name; - newlib->resolved = 1; - newlib->next = NULL; - -#if 0 - //printf("find_elf_interpreter is adding '%s' to '%s'\n", newlib->name, newlib->path); - if (!lib_list) { - lib_list = newlib; - } else { - for (cur = lib_list; cur->next; cur=cur->next); /* nothing */ - cur->next = newlib; - } -#endif - interpreter_already_found=1; - return newlib; - } - return NULL; -} - -/* map the .so, and locate interesting pieces */ -int find_dependancies(char* filename) -{ - int is_suid = 0; - FILE *thefile; - struct stat statbuf; - char *dynstr=NULL; - Elf32_Ehdr *ehdr = NULL; - Elf32_Shdr *dynsec = NULL; - Elf32_Dyn *dynamic = NULL; - struct library *interp; - - if (filename == not_found) - return 0; - - if (!filename) { - fprintf(stderr, "No filename specified.\n"); - return -1; - } - if (!(thefile = fopen(filename, "r"))) { - perror(filename); - return -1; - } - if (fstat(fileno(thefile), &statbuf) < 0) { - perror(filename); - return -1; - } - - if ((size_t)statbuf.st_size < sizeof(Elf32_Ehdr)) - goto foo; - - if (!S_ISREG(statbuf.st_mode)) - goto foo; - - /* mmap the file to make reading stuff from it effortless */ - ehdr = (Elf32_Ehdr *)mmap(0, statbuf.st_size, - PROT_READ|PROT_WRITE, MAP_PRIVATE, fileno(thefile), 0); - -foo: - /* Check if this looks like a legit ELF file */ - if (check_elf_header(ehdr)) { - fprintf(stderr, "%s: not an ELF file.\n", filename); - return -1; - } - /* Check if this is the right kind of ELF file */ - if (ehdr->e_type != ET_EXEC && ehdr->e_type != ET_DYN) { - fprintf(stderr, "%s: not a dynamic executable\n", filename); - return -1; - } - if (ehdr->e_type == ET_EXEC) { - if (statbuf.st_mode & S_ISUID) - is_suid = 1; - if ((statbuf.st_mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) - is_suid = 1; - /* FIXME */ - if (is_suid) - fprintf(stderr, "%s: is setuid\n", filename); - } - - interpreter_already_found=0; - interp = find_elf_interpreter(ehdr); - -#ifdef __LDSO_LDD_SUPPORT - if (interp && ehdr->e_type == ET_EXEC && ehdr->e_ident[EI_CLASS] == ELFCLASSM && - ehdr->e_ident[EI_DATA] == ELFDATAM - && ehdr->e_ident[EI_VERSION] == EV_CURRENT && MATCH_MACHINE(ehdr->e_machine)) - { - struct stat statbuf; - if (stat(interp->path, &statbuf) == 0 && S_ISREG(statbuf.st_mode)) { - pid_t pid; - int status; - static const char * const environment[] = { - "PATH=/usr/bin:/bin:/usr/sbin:/sbin", - "SHELL=/bin/sh", - "LD_TRACE_LOADED_OBJECTS=1", - NULL - }; - - if ((pid = fork()) == 0) { - /* Cool, it looks like we should be able to actually - * run this puppy. Do so now... */ - execle(filename, filename, NULL, environment); - _exit(0xdead); - } - - /* Wait till it returns */ - waitpid(pid, &status, 0); - if (WIFEXITED(status) && WEXITSTATUS(status)==0) { - return 1; - } - - /* If the exec failed, we fall through to trying to find - * all the needed libraries ourselves by rummaging about - * in the ELF headers... */ - } - } -#endif - - dynsec = elf_find_section_type(SHT_DYNAMIC, ehdr); - if (dynsec) { - dynamic = (Elf32_Dyn*)(byteswap32_to_host(dynsec->sh_offset) + (intptr_t)ehdr); - dynstr = (char *)elf_find_dynamic(DT_STRTAB, dynamic, ehdr, 0); - find_needed_libraries(ehdr, dynamic, dynstr, is_suid); - } - - return 0; -} - - - -int main( int argc, char** argv) -{ - int multi=0; - int got_em_all=1; - char *filename = NULL; - struct library *cur; - - if (argc < 2) { - fprintf(stderr, "ldd: missing file arguments\n"); - fprintf(stderr, "Try `ldd --help' for more information.\n"); - exit(EXIT_FAILURE); - } - if (argc > 2) { - multi++; - } - - while (--argc > 0) { - ++argv; - - if(strcmp(*argv, "--")==0) { - /* Ignore "--" */ - continue; - } - - if(strcmp(*argv, "--help")==0) { - fprintf(stderr, "Usage: ldd [OPTION]... FILE...\n"); - fprintf(stderr, "\t--help\t\tprint this help and exit\n"); - exit(EXIT_FAILURE); - } - - filename=*argv; - if (!filename) { - fprintf(stderr, "No filename specified.\n"); - exit(EXIT_FAILURE); - } - - if (multi) { - printf("%s:\n", *argv); - } - - if (find_dependancies(filename)!=0) - continue; - - while(got_em_all) { - got_em_all=0; - /* Keep walking the list till everybody is resolved */ - for (cur = lib_list; cur; cur=cur->next) { - if (cur->resolved == 0 && cur->path) { - got_em_all=1; - //printf("checking sub-depends for '%s\n", cur->path); - find_dependancies(cur->path); - cur->resolved = 1; - } - } - } - - - /* Print the list */ - got_em_all=0; - for (cur = lib_list; cur; cur=cur->next) { - got_em_all=1; - printf("\t%s => %s (0x00000000)\n", cur->name, cur->path); - } - if (interp_dir && got_em_all==1) - printf("\t%s => %s (0x00000000)\n", interp, interp); - if (got_em_all==0) - printf("\tnot a dynamic executable\n"); - - for (cur = lib_list; cur; cur=cur->next) { - free(cur->name); - cur->name=NULL; - free(cur->path); - cur->path=NULL; - } - lib_list=NULL; - } - - return 0; -} - |