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/* vi: set sw=4 ts=4: */

/* Program to load an ELF binary on a linux system, and run it

 * after resolving ELF shared library symbols

 *

 * Copyright (c) 1994-2000 Eric Youngdale, Peter MacDonald,

 *                              David Engel, Hongjiu Lu and Mitch D'Souza

 * Copyright (C) 2001-2002, Erik Andersen

 *

 * All rights reserved.

 *

 * 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. The name of the above contributors may not be

 *    used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``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 THE 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.

 */

// Support a list of library preloads in /etc/ld.so.preload

//#define SUPPORT_LDSO_PRELOAD_FILE

/* Disclaimer:  I have never seen any AT&T source code for SVr4, nor have

   I ever taken any courses on internals.  This program was developed using

   information available through the book "UNIX SYSTEM V RELEASE 4,

   Programmers guide: Ansi C and Programming Support Tools", which did

   a more than adequate job of explaining everything required to get this

   working. */

/*

 * The main trick with this program is that initially, we ourselves are

 * not dynamicly linked.  This means that we cannot access any global

 * variables or call any functions.  No globals initially, since the

 * Global Offset Table (GOT) is initialized by the linker assuming a

 * virtual address of 0, and no function calls initially since the

 * Procedure Linkage Table (PLT) is not yet initialized.

 *

 * There are additional initial restrictions - we cannot use large

 * switch statements, since the compiler generates tables of addresses

 * and jumps through them.  We can use inline functions, because these

 * do not transfer control to a new address, but they must be static so

 * that they are not exported from the modules.  We cannot use normal

 * syscall stubs, because these all reference the errno global variable

 * which is not yet initialized.  We can use all of the local stack

 * variables that we want.

 *

 * Life is further complicated by the fact that initially we do not

 * want to do a complete dynamic linking.  We want to allow the user to

 * supply new functions to override symbols (i.e. weak symbols and/or

 * LD_PRELOAD).  So initially, we only perform relocations for

 * variables that start with "_dl_" since ANSI specifies that the user

 * is not supposed to redefine any of these variables.

 *

 * Fortunately, the linker itself leaves a few clues lying around, and

 * when the kernel starts the image, there are a few further clues.

 * First of all, there is Auxiliary Vector Table information sitting on

 * which is provided to us by the kernel, and which includes

 * information about the load address that the program interpreter was

 * loaded at, the number of sections, the address the application was

 * loaded at and so forth.  Here this information is stored in the

 * array auxvt.  For details see linux/fs/binfmt_elf.c where it calls

 * NEW_AUX_ENT() a bunch of time....

 *

 * Next, we need to find the GOT.  On most arches there is a register

 * pointing to the GOT, but just in case (and for new ports) I've added

 * some (slow) C code to locate the GOT for you.

 *

 * This code was originally written for SVr4, and there the kernel

 * would load all text pages R/O, so they needed to call mprotect a

 * zillion times to mark all text pages as writable so dynamic linking

 * would succeed.  Then when they were done, they would change the

 * protections for all the pages back again.  Well, under Linux

 * everything is loaded writable (since Linux does copy on write

 * anyways) so all the mprotect stuff has been disabled.

 *

 * Initially, we do not have access to _dl_malloc since we can't yet

 * make function calls, so we mmap one page to use as scratch space.

 * Later on, when we can call _dl_malloc we reuse this this memory.

 * This is also beneficial, since we do not want to use the same memory

 * pool as malloc anyway - esp if the user redefines malloc to do

 * something funky.

 *

 * Our first task is to perform a minimal linking so that we can call

 * other portions of the dynamic linker.  Once we have done this, we

 * then build the list of modules that the application requires, using

 * LD_LIBRARY_PATH if this is not a suid program (/usr/lib otherwise).

 * Once this is done, we can do the dynamic linking as required, and we

 * must omit the things we did to get the dynamic linker up and running

 * in the first place.  After we have done this, we just have a few

 * housekeeping chores and we can transfer control to the user's

 * application.

 */

#include "ldso.h"

#define ALLOW_ZERO_PLTGOT

/*  Some arches may need to override this in boot1_arch.h */

#define     ELFMAGIC    ELFMAG

/* This is a poor man's malloc, used prior to resolving our internal poor man's malloc */

#define LD_MALLOC(SIZE) ((void *) (malloc_buffer += SIZE, malloc_buffer - SIZE)) ;  REALIGN();

/*

 * Make sure that the malloc buffer is aligned on 4 byte boundary.  For 64 bit

 * platforms we may need to increase this to 8, but this is good enough for

 * now.  This is typically called after LD_MALLOC.

 */

#define REALIGN() malloc_buffer = (char *) (((unsigned long) malloc_buffer + 3) & ~(3))

char *_dl_library_path = 0;              /* Where we look for libraries */

char *_dl_preload = 0;                   /* Things to be loaded before the libs. */

char *_dl_ldsopath = 0;

static int _dl_be_lazy = RTLD_LAZY;

#ifdef __SUPPORT_LD_DEBUG__

char *_dl_debug  = 0;

char *_dl_debug_symbols = 0;

char *_dl_debug_move    = 0;

char *_dl_debug_reloc   = 0;

char *_dl_debug_detail  = 0;

char *_dl_debug_nofixups  = 0;

char *_dl_debug_bindings  = 0;

int   _dl_debug_file = 2;

#else

#define _dl_debug_file 2

#endif

static char *_dl_malloc_addr, *_dl_mmap_zero;

static char *_dl_trace_loaded_objects = 0;

static int (*_dl_elf_main) (int, char **, char **);

struct r_debug *_dl_debug_addr = NULL;

unsigned long *_dl_brkp;

unsigned long *_dl_envp;

int _dl_fixup(struct elf_resolve *tpnt, int lazy);

void _dl_debug_state(void);

char *_dl_get_last_path_component(char *path);

static void _dl_get_ready_to_run(struct elf_resolve *tpnt, struct elf_resolve *app_tpnt,

                unsigned long load_addr, unsigned long *hash_addr, Elf32_auxv_t auxvt[AT_EGID + 1],

                char **envp, struct r_debug *debug_addr);

#include "boot1_arch.h"

#include "_dl_progname.h"                               /* Pull in the value of _dl_progname */

/* When we enter this piece of code, the program stack looks like this:

        argc            argument counter (integer)

        argv[0]         program name (pointer)

        argv[1...N]     program args (pointers)

        argv[argc-1]    end of args (integer)

                NULL

        env[0...N]      environment variables (pointers)

        NULL

                auxvt[0...N]   Auxiliary Vector Table elements (mixed types)

*/

#ifdef __SUPPORT_LD_DEBUG_EARLY__

/* Debugging is especially tricky on PowerPC, since string literals

 * require relocations.  Thus, you can't use _dl_dprintf() for

 * anything until the bootstrap relocations are finished. */

static inline void hexprint(unsigned long x)

{

        int i;

        char c;

        for (i = 0; i < 8; i++) {

                c = ((x >> 28) + '0');

                if (c > '9')

                        c += 'a' - '9' - 1;

                _dl_write(1, &c, 1);

                x <<= 4;

        }

        c = '\n';

        _dl_write(1, &c, 1);

}

#endif

LD_BOOT(unsigned long args) __attribute__ ((unused));

LD_BOOT(unsigned long args)

{

        unsigned int argc;

        char **argv, **envp;

        unsigned long load_addr;

        unsigned long *got;

        unsigned long *aux_dat;

        int goof = 0;

        ElfW(Ehdr) *header;

        struct elf_resolve *tpnt;

        struct elf_resolve *app_tpnt;

        Elf32_auxv_t auxvt[AT_EGID + 1];

        unsigned char *malloc_buffer, *mmap_zero;

        Elf32_Dyn *dpnt;

        unsigned long *hash_addr;

        struct r_debug *debug_addr = NULL;

        int indx;

        int status;

        /* WARNING! -- we cannot make _any_ funtion calls until we have

         * taken care of fixing up our own relocations.  Making static

         * inline calls is ok, but _no_ function calls.  Not yet

         * anyways. */

        /* First obtain the information on the stack that tells us more about

           what binary is loaded, where it is loaded, etc, etc */

        GET_ARGV(aux_dat, args);

#if defined (__arm__) || defined (__mips__) || defined (__cris__)

        aux_dat += 1;

#endif

        argc = *(aux_dat - 1);

        argv = (char **) aux_dat;

        aux_dat += argc;                        /* Skip over the argv pointers */

        aux_dat++;                                      /* Skip over NULL at end of argv */

        envp = (char **) aux_dat;

        while (*aux_dat)

                aux_dat++;                              /* Skip over the envp pointers */

        aux_dat++;                                      /* Skip over NULL at end of envp */

        /* Place -1 here as a checkpoint.  We later check if it was changed

         * when we read in the auxvt */

        auxvt[AT_UID].a_type = -1;

        /* The junk on the stack immediately following the environment is

         * the Auxiliary Vector Table.  Read out the elements of the auxvt,

         * sort and store them in auxvt for later use. */

        while (*aux_dat) {

                Elf32_auxv_t *auxv_entry = (Elf32_auxv_t *) aux_dat;

                if (auxv_entry->a_type <= AT_EGID) {

                        _dl_memcpy(&(auxvt[auxv_entry->a_type]), auxv_entry, sizeof(Elf32_auxv_t));

                }

                aux_dat += 2;

        }

        /* locate the ELF header.   We need this done as soon as possible

         * (esp since SEND_STDERR() needs this on some platforms... */

        load_addr = auxvt[AT_BASE].a_un.a_val;

        header = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_ptr;

        /* Check the ELF header to make sure everything looks ok.  */

        if (!header || header->e_ident[EI_CLASS] != ELFCLASS32 ||

                header->e_ident[EI_VERSION] != EV_CURRENT

#if !defined(__powerpc__) && !defined(__mips__) && !defined(__sh__)

                || _dl_strncmp((void *) header, ELFMAGIC, SELFMAG) != 0

#else

                || header->e_ident[EI_MAG0] != ELFMAG0

                || header->e_ident[EI_MAG1] != ELFMAG1

                || header->e_ident[EI_MAG2] != ELFMAG2

                || header->e_ident[EI_MAG3] != ELFMAG3

#endif

                ) {

                SEND_STDERR("Invalid ELF header\n");

                _dl_exit(0);

        }

#ifdef __SUPPORT_LD_DEBUG_EARLY__

        SEND_STDERR("ELF header=");

        SEND_ADDRESS_STDERR(load_addr, 1);

#endif

        /* Locate the global offset table.  Since this code must be PIC

         * we can take advantage of the magic offset register, if we

         * happen to know what that is for this architecture.  If not,

         * we can always read stuff out of the ELF file to find it... */

#if defined(__i386__)

  __asm__("\tmovl %%ebx,%0\n\t":"=a"(got));

#elif defined(__m68k__)

  __asm__("movel %%a5,%0":"=g"(got))

#elif defined(__sparc__)

  __asm__("\tmov %%l7,%0\n\t":"=r"(got))

#elif defined(__arm__)

  __asm__("\tmov %0, r10\n\t":"=r"(got));

#elif defined(__powerpc__)

  __asm__("\tbl _GLOBAL_OFFSET_TABLE_-4@local\n\t":"=l"(got));

#elif defined(__mips__)

  __asm__("\tmove %0, $28\n\tsubu %0,%0,0x7ff0\n\t":"=r"(got));

#elif defined(__sh__) && !defined(__SH5__)

  __asm__(

"       mov.l    1f, %0\n"

"       mova     1f, r0\n"

"       bra      2f\n"

"       add r0,  %0\n"

"       .balign  4\n"

"1:     .long    _GLOBAL_OFFSET_TABLE_\n"

"2:" : "=r" (got) : : "r0");

#elif defined(__cris__)

  __asm__("\tmove.d $pc,%0\n\tsub.d .:GOTOFF,%0\n\t":"=r"(got));

#else

        /* Do things the slow way in C */

        {

                unsigned long tx_reloc;

                Elf32_Dyn *dynamic = NULL;

                Elf32_Shdr *shdr;

                Elf32_Phdr *pt_load;

#ifdef __SUPPORT_LD_DEBUG_EARLY__

                SEND_STDERR("Finding the GOT using C code to read the ELF file\n");

#endif

                /* Find where the dynamic linking information section is hiding */

                shdr = (Elf32_Shdr *) (header->e_shoff + (char *) header);

                for (indx = header->e_shnum; --indx >= 0; ++shdr) {

                        if (shdr->sh_type == SHT_DYNAMIC) {

                                goto found_dynamic;

                        }

                }

                SEND_STDERR("missing dynamic linking information section \n");

                _dl_exit(0);

          found_dynamic:

                dynamic = (Elf32_Dyn *) (shdr->sh_offset + (char *) header);

                /* Find where PT_LOAD is hiding */

                pt_load = (Elf32_Phdr *) (header->e_phoff + (char *) header);

                for (indx = header->e_phnum; --indx >= 0; ++pt_load) {

                        if (pt_load->p_type == PT_LOAD) {

                                goto found_pt_load;

                        }

                }

                SEND_STDERR("missing loadable program segment\n");

                _dl_exit(0);

          found_pt_load:

                /* Now (finally) find where DT_PLTGOT is hiding */

                tx_reloc = pt_load->p_vaddr - pt_load->p_offset;

                for (; DT_NULL != dynamic->d_tag; ++dynamic) {

                        if (dynamic->d_tag == DT_PLTGOT) {

                                goto found_got;

                        }

                }

                SEND_STDERR("missing global offset table\n");

                _dl_exit(0);

          found_got:

                got = (unsigned long *) (dynamic->d_un.d_val - tx_reloc +

                                (char *) header);

        }

#endif

        /* Now, finally, fix up the location of the dynamic stuff */

        dpnt = (Elf32_Dyn *) (*got + load_addr);

#ifdef __SUPPORT_LD_DEBUG_EARLY__

        SEND_STDERR("First Dynamic section entry=");

        SEND_ADDRESS_STDERR(dpnt, 1);

#endif

        /* Call mmap to get a page of writable memory that can be used

         * for _dl_malloc throughout the shared lib loader. */

        mmap_zero = malloc_buffer = _dl_mmap((void *) 0, PAGE_SIZE,

                        PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);

        if (_dl_mmap_check_error(mmap_zero)) {

                SEND_STDERR("dl_boot: mmap of a spare page failed!\n");

                _dl_exit(13);

        }

        tpnt = LD_MALLOC(sizeof(struct elf_resolve));

        _dl_memset(tpnt, 0, sizeof(struct elf_resolve));

        app_tpnt = LD_MALLOC(sizeof(struct elf_resolve));

        _dl_memset(app_tpnt, 0, sizeof(struct elf_resolve));

#ifdef __UCLIBC_PIE_SUPPORT__

        /* Find the runtime load address of the main executable, this may be

         * different from what the ELF header says for ET_DYN/PIE executables.

         */

        {

                ElfW(Phdr) *ppnt;

                int i;

                ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_ptr;

                for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++)

                        if (ppnt->p_type == PT_PHDR) {

                                app_tpnt->loadaddr = (ElfW(Addr)) (auxvt[AT_PHDR].a_un.a_val - ppnt->p_vaddr);

                                break;

                        }

        }

#ifdef __SUPPORT_LD_DEBUG_EARLY__

        SEND_STDERR("app_tpnt->loadaddr=");

        SEND_ADDRESS_STDERR(app_tpnt->loadaddr, 1);

#endif

#endif

        /*

         * This is used by gdb to locate the chain of shared libraries that are currently loaded.

         */

        debug_addr = LD_MALLOC(sizeof(struct r_debug));

        _dl_memset(debug_addr, 0, sizeof(struct r_debug));

        /* OK, that was easy.  Next scan the DYNAMIC section of the image.

           We are only doing ourself right now - we will have to do the rest later */

#ifdef __SUPPORT_LD_DEBUG_EARLY__

        SEND_STDERR("scanning DYNAMIC section\n");

#endif

        while (dpnt->d_tag) {

#if defined(__mips__)

                if (dpnt->d_tag == DT_MIPS_GOTSYM)

                        tpnt->mips_gotsym = (unsigned long) dpnt->d_un.d_val;

                if (dpnt->d_tag == DT_MIPS_LOCAL_GOTNO)

                        tpnt->mips_local_gotno = (unsigned long) dpnt->d_un.d_val;

                if (dpnt->d_tag == DT_MIPS_SYMTABNO)

                        tpnt->mips_symtabno = (unsigned long) dpnt->d_un.d_val;

#endif

                if (dpnt->d_tag < 24) {

                        tpnt->dynamic_info[dpnt->d_tag] = dpnt->d_un.d_val;

                        if (dpnt->d_tag == DT_TEXTREL) {

                                tpnt->dynamic_info[DT_TEXTREL] = 1;

                        }

                }

                dpnt++;

        }

        {

                ElfW(Phdr) *ppnt;

                int i;

                ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_ptr;

                for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++)

                        if (ppnt->p_type == PT_DYNAMIC) {

#ifndef __UCLIBC_PIE_SUPPORT__

                                dpnt = (Elf32_Dyn *) ppnt->p_vaddr;

#else

                                dpnt = (Elf32_Dyn *) (ppnt->p_vaddr + app_tpnt->loadaddr);

#endif

                                while (dpnt->d_tag) {

#if defined(__mips__)

                                        if (dpnt->d_tag == DT_MIPS_GOTSYM)

                                                app_tpnt->mips_gotsym =

                                                        (unsigned long) dpnt->d_un.d_val;

                                        if (dpnt->d_tag == DT_MIPS_LOCAL_GOTNO)

                                                app_tpnt->mips_local_gotno =

                                                        (unsigned long) dpnt->d_un.d_val;

                                        if (dpnt->d_tag == DT_MIPS_SYMTABNO)

                                                app_tpnt->mips_symtabno =

                                                        (unsigned long) dpnt->d_un.d_val;

                                        if (dpnt->d_tag > DT_JMPREL) {

                                                dpnt++;

                                                continue;

                                        }

                                        app_tpnt->dynamic_info[dpnt->d_tag] = dpnt->d_un.d_val;

#warning "Debugging threads on mips won't work till someone fixes this..."

#if 0

                                        if (dpnt->d_tag == DT_DEBUG) {

                                                dpnt->d_un.d_val = (unsigned long) debug_addr;

                                        }

#endif

#else

                                        if (dpnt->d_tag > DT_JMPREL) {

                                                dpnt++;

                                                continue;

                                        }

                                        app_tpnt->dynamic_info[dpnt->d_tag] = dpnt->d_un.d_val;

                                        if (dpnt->d_tag == DT_DEBUG) {

                                                dpnt->d_un.d_val = (unsigned long) debug_addr;

                                        }

#endif

                                        if (dpnt->d_tag == DT_TEXTREL)

                                                app_tpnt->dynamic_info[DT_TEXTREL] = 1;

                                        dpnt++;

                                }

                        }

        }

#ifdef __SUPPORT_LD_DEBUG_EARLY__

        SEND_STDERR("done scanning DYNAMIC section\n");

#endif

        /* Get some more of the information that we will need to dynamicly link

           this module to itself */

        hash_addr = (unsigned long *) (tpnt->dynamic_info[DT_HASH] + load_addr);

        tpnt->nbucket = *hash_addr++;

        tpnt->nchain = *hash_addr++;

        tpnt->elf_buckets = hash_addr;

        hash_addr += tpnt->nbucket;

#ifdef __SUPPORT_LD_DEBUG_EARLY__

        SEND_STDERR("done grabbing link information\n");

#endif

#ifndef FORCE_SHAREABLE_TEXT_SEGMENTS

        /* Ugly, ugly.  We need to call mprotect to change the protection of

           the text pages so that we can do the dynamic linking.  We can set the

           protection back again once we are done */

        {

                ElfW(Phdr) *ppnt;

                int i;

#ifdef __SUPPORT_LD_DEBUG_EARLY__

                SEND_STDERR("calling mprotect on the shared library/dynamic linker\n");

#endif

                /* First cover the shared library/dynamic linker. */

                if (tpnt->dynamic_info[DT_TEXTREL]) {

                        header = (ElfW(Ehdr) *) auxvt[AT_BASE].a_un.a_ptr;

                        ppnt = (ElfW(Phdr) *) ((int)auxvt[AT_BASE].a_un.a_ptr +

                                        header->e_phoff);

                        for (i = 0; i < header->e_phnum; i++, ppnt++) {

                                if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W)) {

                                        _dl_mprotect((void *) (load_addr + (ppnt->p_vaddr & PAGE_ALIGN)),

                                                        (ppnt->p_vaddr & ADDR_ALIGN) + (unsigned long) ppnt->p_filesz,

                                                        PROT_READ | PROT_WRITE | PROT_EXEC);

                                }

                        }

                }

#ifdef __SUPPORT_LD_DEBUG_EARLY__

                SEND_STDERR("calling mprotect on the application program\n");

#endif

                /* Now cover the application program. */

                if (app_tpnt->dynamic_info[DT_TEXTREL]) {

                        ppnt = (ElfW(Phdr) *) auxvt[AT_PHDR].a_un.a_ptr;

                        for (i = 0; i < auxvt[AT_PHNUM].a_un.a_val; i++, ppnt++) {

                                if (ppnt->p_type == PT_LOAD && !(ppnt->p_flags & PF_W))

#ifndef __UCLIBC_PIE_SUPPORT__

                                        _dl_mprotect((void *) (ppnt->p_vaddr & PAGE_ALIGN),

                                                                 (ppnt->p_vaddr & ADDR_ALIGN) +

#else

                                        _dl_mprotect((void *) ((ppnt->p_vaddr + app_tpnt->loadaddr) & PAGE_ALIGN),

                                                                 ((ppnt->p_vaddr + app_tpnt->loadaddr) & ADDR_ALIGN) +

#endif

                                                                 (unsigned long) ppnt->p_filesz,

                                                                 PROT_READ | PROT_WRITE | PROT_EXEC);

                        }

                }

        }

#endif

#if defined(__mips__)

#ifdef __SUPPORT_LD_DEBUG_EARLY__

        SEND_STDERR("About to do MIPS specific GOT bootstrap\n");

#endif

        /* For MIPS we have to do stuff to the GOT before we do relocations.  */

        PERFORM_BOOTSTRAP_GOT(got);

#endif

        /* OK, now do the relocations.  We do not do a lazy binding here, so

           that once we are done, we have considerably more flexibility. */

#ifdef __SUPPORT_LD_DEBUG_EARLY__

        SEND_STDERR("About to do library loader relocations\n");

#endif

        goof = 0;

        for (indx = 0; indx < 2; indx++) {

                unsigned int i;

                ELF_RELOC *rpnt;

                unsigned long *reloc_addr;

                unsigned long symbol_addr;

                int symtab_index;

                unsigned long rel_addr, rel_size;

#ifdef ELF_USES_RELOCA

                rel_addr = (indx ? tpnt->dynamic_info[DT_JMPREL] : tpnt->

                         dynamic_info[DT_RELA]);

                rel_size = (indx ? tpnt->dynamic_info[DT_PLTRELSZ] : tpnt->

                         dynamic_info[DT_RELASZ]);

#else

                rel_addr = (indx ? tpnt->dynamic_info[DT_JMPREL] : tpnt->

                         dynamic_info[DT_REL]);

                rel_size = (indx ? tpnt->dynamic_info[DT_PLTRELSZ] : tpnt->

                         dynamic_info[DT_RELSZ]);

#endif

                if (!rel_addr)

                        continue;

                /* Now parse the relocation information */

                rpnt = (ELF_RELOC *) (rel_addr + load_addr);

                for (i = 0; i < rel_size; i += sizeof(ELF_RELOC), rpnt++) {

                        reloc_addr = (unsigned long *) (load_addr + (unsigned long) rpnt->r_offset);

                        symtab_index = ELF32_R_SYM(rpnt->r_info);

                        symbol_addr = 0;

                        if (symtab_index) {

                                char *strtab;

                                Elf32_Sym *symtab;

                                symtab = (Elf32_Sym *) (tpnt->dynamic_info[DT_SYMTAB] + load_addr);

                                strtab = (char *) (tpnt->dynamic_info[DT_STRTAB] + load_addr);

                                /* We only do a partial dynamic linking right now.  The user

                                   is not supposed to redefine any symbols that start with

                                   a '_', so we can do this with confidence. */

                                if (!_dl_symbol(strtab + symtab[symtab_index].st_name))

                                        continue;

                                symbol_addr = load_addr + symtab[symtab_index].st_value;

                                if (!symbol_addr) {

                                        /* This will segfault - you cannot call a function until

                                         * we have finished the relocations.

                                         */

                                        SEND_STDERR("ELF dynamic loader - unable to self-bootstrap - symbol ");

                                        SEND_STDERR(strtab + symtab[symtab_index].st_name);

                                        SEND_STDERR(" undefined.\n");

                                        goof++;

                                }

#ifdef __SUPPORT_LD_DEBUG_EARLY__

                                SEND_STDERR("About to fixup symbol: ");

                                SEND_STDERR(strtab + symtab[symtab_index].st_name);

                                SEND_STDERR("\n");

#endif  

                                PERFORM_BOOTSTRAP_RELOC(rpnt, reloc_addr, symbol_addr, load_addr, &symtab[symtab_index]);

                        } else {

                                /*

                                 * Use this machine-specific macro to perform the actual relocation.

                                 */

                                PERFORM_BOOTSTRAP_RELOC(rpnt, reloc_addr, symbol_addr, load_addr, NULL);

                        }

                }

        }

        if (goof) {

                _dl_exit(14);

        }

#ifdef __SUPPORT_LD_DEBUG_EARLY__

        /* Wahoo!!! */

        _dl_dprintf(_dl_debug_file, "Done relocating library loader, so we can now\n\tuse globals and make function calls!\n");

#endif

        if (argv[0]) {

                _dl_progname = argv[0];

        }

        /* Start to build the tables of the modules that are required for

         * this beast to run.  We start with the basic executable, and then

         * go from there.  Eventually we will run across ourself, and we

         * will need to properly deal with that as well. */

        /* Make it so _dl_malloc can use the page of memory we have already

         * allocated, so we shouldn't need to grab any more memory */

        _dl_malloc_addr = malloc_buffer;

        _dl_mmap_zero = mmap_zero;

        /* Now we have done the mandatory linking of some things.  We are now

           free to start using global variables, since these things have all been

           fixed up by now.  Still no function calls outside of this library ,

           since the dynamic resolver is not yet ready. */

        _dl_get_ready_to_run(tpnt, app_tpnt, load_addr, hash_addr, auxvt, envp, debug_addr);

        /* Notify the debugger that all objects are now mapped in.  */

        _dl_debug_addr->r_state = RT_CONSISTENT;

        _dl_debug_state();

        /* OK we are done here.  Turn out the lights, and lock up. */

        _dl_elf_main = (int (*)(int, char **, char **)) auxvt[AT_ENTRY].a_un.a_fcn;

        /*

         * Transfer control to the application.

         */

        status = 0;                                      /* Used on x86, but not on other arches */

#if defined (__SUPPORT_LD_DEBUG__)

        if(_dl_debug) _dl_dprintf(_dl_debug_file,"\ntransfering control: %s\n\n", _dl_progname);

#endif