insmod.c

/* vi: set sw=4 ts=4: */
/*
 * Mini insmod implementation for busybox
 *
 * Copyright (C) 1999,2000 by Lineo, inc.
 * Written by Erik Andersen <andersen@lineo.com>
 * and Ron Alder <alder@lineo.com>
 *
 * Based almost entirely on the Linux modutils-2.3.11 implementation.
 *   Copyright 1996, 1997 Linux International.
 *   New implementation contributed by Richard Henderson <rth@tamu.edu>
 *   Based on original work by Bjorn Ekwall <bj0rn@blox.se>
 *   Restructured (and partly rewritten) by:
 *   Björn Ekwall <bj0rn@blox.se> February 1999
 *
 * 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
 *
 */

#include "internal.h"
#include <stdlib.h>
#include <stdio.h>
#include <stddef.h>
#include <errno.h>
#include <unistd.h>
#include <dirent.h>
#include <ctype.h>
#include <assert.h>
#include <sys/utsname.h>
#include <sys/syscall.h>
#include <linux/unistd.h>

//----------------------------------------------------------------------------
//--------modutils module.h, lines 45-242
//----------------------------------------------------------------------------

/* Definitions for the Linux module syscall interface.
   Copyright 1996, 1997 Linux International.

   Contributed by Richard Henderson <rth@tamu.edu>

   This file is part of the Linux modutils.

   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.  */


#ifndef MODUTILS_MODULE_H
#define MODUTILS_MODULE_H 1

#ident "$Id: insmod.c,v 1.9 2000/06/19 19:53:30 andersen Exp $"

/* This file contains the structures used by the 2.0 and 2.1 kernels.
   We do not use the kernel headers directly because we do not wish
   to be dependant on a particular kernel version to compile insmod.  */


/*======================================================================*/
/* The structures used by Linux 2.0.  */

/* The symbol format used by get_kernel_syms(2).  */
struct old_kernel_sym
{
  unsigned long value;
  char name[60];
};

struct old_module_ref
{
  unsigned long module;		/* kernel addresses */
  unsigned long next;
};

struct old_module_symbol
{
  unsigned long addr;
  unsigned long name;
};

struct old_symbol_table
{
  int size;			/* total, including string table!!! */
  int n_symbols;
  int n_refs;
  struct old_module_symbol symbol[0]; /* actual size defined by n_symbols */
  struct old_module_ref ref[0];	/* actual size defined by n_refs */
};

struct old_mod_routines
{
  unsigned long init;
  unsigned long cleanup;
};

struct old_module
{
  unsigned long next;
  unsigned long ref;		/* the list of modules that refer to me */
  unsigned long symtab;
  unsigned long name;
  int size;			/* size of module in pages */
  unsigned long addr;		/* address of module */
  int state;
  unsigned long cleanup;	/* cleanup routine */
};

/* Sent to init_module(2) or'ed into the code size parameter.  */
#define OLD_MOD_AUTOCLEAN 0x40000000 /* big enough, but no sign problems... */

int get_kernel_syms(struct old_kernel_sym *);
int old_sys_init_module(const char *name, char *code, unsigned codesize,
			struct old_mod_routines *, struct old_symbol_table *);

/*======================================================================*/
/* For sizeof() which are related to the module platform and not to the
   environment isnmod is running in, use sizeof_xx instead of sizeof(xx).  */

#define tgt_sizeof_char		sizeof(char)
#define tgt_sizeof_short	sizeof(short)
#define tgt_sizeof_int		sizeof(int)
#define tgt_sizeof_long		sizeof(long)
#define tgt_sizeof_char_p	sizeof(char *)
#define tgt_sizeof_void_p	sizeof(void *)
#define tgt_long		long

#if defined(__sparc__) && !defined(__sparc_v9__) && defined(ARCH_sparc64)
#undef tgt_sizeof_long
#undef tgt_sizeof_char_p
#undef tgt_sizeof_void_p
#undef tgt_long
#define tgt_sizeof_long		8
#define tgt_sizeof_char_p	8
#define tgt_sizeof_void_p	8
#define tgt_long		long long
#endif

/*======================================================================*/
/* The structures used in Linux 2.1.  */

/* Note: new_module_symbol does not use tgt_long intentionally */
struct new_module_symbol
{
  unsigned long value;
  unsigned long name;
};

struct new_module_persist;

struct new_module_ref
{
  unsigned tgt_long dep;		/* kernel addresses */
  unsigned tgt_long ref;
  unsigned tgt_long next_ref;
};

struct new_module
{
  unsigned tgt_long size_of_struct;	/* == sizeof(module) */
  unsigned tgt_long next;
  unsigned tgt_long name;
  unsigned tgt_long size;

  tgt_long usecount;
  unsigned tgt_long flags;		/* AUTOCLEAN et al */

  unsigned nsyms;
  unsigned ndeps;

  unsigned tgt_long syms;
  unsigned tgt_long deps;
  unsigned tgt_long refs;
  unsigned tgt_long init;
  unsigned tgt_long cleanup;
  unsigned tgt_long ex_table_start;
  unsigned tgt_long ex_table_end;
#ifdef __alpha__
  unsigned tgt_long gp;
#endif
  /* Everything after here is extension.  */
  unsigned tgt_long persist_start;
  unsigned tgt_long persist_end;
  unsigned tgt_long can_unload;
  unsigned tgt_long runsize;
};

struct new_module_info
{
  unsigned long addr;
  unsigned long size;
  unsigned long flags;
	   long usecount;
};

/* Bits of module.flags.  */
#define NEW_MOD_RUNNING		1
#define NEW_MOD_DELETED		2
#define NEW_MOD_AUTOCLEAN	4
#define NEW_MOD_VISITED		8
#define NEW_MOD_USED_ONCE	16

int new_sys_init_module(const char *name, const struct new_module *);
int query_module(const char *name, int which, void *buf, size_t bufsize,
		 size_t *ret);

/* Values for query_module's which.  */

#define QM_MODULES	1
#define QM_DEPS		2
#define QM_REFS		3
#define QM_SYMBOLS	4
#define QM_INFO		5

/*======================================================================*/
/* The system calls unchanged between 2.0 and 2.1.  */

unsigned long create_module(const char *, size_t);
int delete_module(const char *);


#endif /* module.h */

//----------------------------------------------------------------------------
//--------end of modutils module.h
//----------------------------------------------------------------------------



//----------------------------------------------------------------------------
//--------modutils obj.h, lines 253-462
//----------------------------------------------------------------------------

/* Elf object file loading and relocation routines.
   Copyright 1996, 1997 Linux International.

   Contributed by Richard Henderson <rth@tamu.edu>

   This file is part of the Linux modutils.

   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.  */


#ifndef MODUTILS_OBJ_H
#define MODUTILS_OBJ_H 1

#ident "$Id: insmod.c,v 1.9 2000/06/19 19:53:30 andersen Exp $"

/* The relocatable object is manipulated using elfin types.  */

#include <stdio.h>
#include <elf.h>


/* Machine-specific elf macros for i386 et al.  */

#define ELFCLASSM	ELFCLASS32
#define ELFDATAM	ELFDATA2LSB

#define MATCH_MACHINE(x)  (x == EM_386 || x == EM_486)

#define SHT_RELM	SHT_REL
#define Elf32_RelM	Elf32_Rel


#ifndef ElfW
# if ELFCLASSM == ELFCLASS32
#  define ElfW(x)  Elf32_ ## x
#  define ELFW(x)  ELF32_ ## x
# else
#  define ElfW(x)  Elf64_ ## x
#  define ELFW(x)  ELF64_ ## x
# endif
#endif

/* For some reason this is missing from libc5.  */
#ifndef ELF32_ST_INFO
# define ELF32_ST_INFO(bind, type)       (((bind) << 4) + ((type) & 0xf))
#endif

#ifndef ELF64_ST_INFO
# define ELF64_ST_INFO(bind, type)       (((bind) << 4) + ((type) & 0xf))
#endif

struct obj_string_patch;
struct obj_symbol_patch;

struct obj_section
{
  ElfW(Shdr) header;
  const char *name;
  char *contents;
  struct obj_section *load_next;
  int idx;
};

struct obj_symbol
{
  struct obj_symbol *next;	/* hash table link */
  const char *name;
  unsigned long value;
  unsigned long size;
  int secidx;			/* the defining section index/module */
  int info;
  int ksymidx;			/* for export to the kernel symtab */
  int referenced;		/* actually used in the link */
};

/* Hardcode the hash table size.  We shouldn't be needing so many
   symbols that we begin to degrade performance, and we get a big win
   by giving the compiler a constant divisor.  */

#define HASH_BUCKETS  521

struct obj_file
{
  ElfW(Ehdr) header;
  ElfW(Addr) baseaddr;
  struct obj_section **sections;
  struct obj_section *load_order;
  struct obj_section **load_order_search_start;
  struct obj_string_patch *string_patches;
  struct obj_symbol_patch *symbol_patches;
  int (*symbol_cmp)(const char *, const char *);
  unsigned long (*symbol_hash)(const char *);
  unsigned long local_symtab_size;
  struct obj_symbol **local_symtab;
  struct obj_symbol *symtab[HASH_BUCKETS];
};

enum obj_reloc
{
  obj_reloc_ok,
  obj_reloc_overflow,
  obj_reloc_dangerous,
  obj_reloc_unhandled
};

struct obj_string_patch
{
  struct obj_string_patch *next;
  int reloc_secidx;
  ElfW(Addr) reloc_offset;
  ElfW(Addr) string_offset;
};

struct obj_symbol_patch
{
  struct obj_symbol_patch *next;
  int reloc_secidx;
  ElfW(Addr) reloc_offset;
  struct obj_symbol *sym;
};


/* Generic object manipulation routines.  */

unsigned long obj_elf_hash(const char *);

unsigned long obj_elf_hash_n(const char *, unsigned long len);

struct obj_symbol *obj_add_symbol (struct obj_file *f, const char *name,
				   unsigned long symidx, int info, int secidx,
				   ElfW(Addr) value, unsigned long size);

struct obj_symbol *obj_find_symbol (struct obj_file *f,
					 const char *name);

ElfW(Addr) obj_symbol_final_value(struct obj_file *f,
				  struct obj_symbol *sym);

void obj_set_symbol_compare(struct obj_file *f,
			    int (*cmp)(const char *, const char *),
			    unsigned long (*hash)(const char *));

struct obj_section *obj_find_section (struct obj_file *f,
					   const char *name);

void obj_insert_section_load_order (struct obj_file *f,
				    struct obj_section *sec);

struct obj_section *obj_create_alloced_section (struct obj_file *f,
						const char *name,
						unsigned long align,
						unsigned long size);

struct obj_section *obj_create_alloced_section_first (struct obj_file *f,
						      const char *name,
						      unsigned long align,
						      unsigned long size);

void *obj_extend_section (struct obj_section *sec, unsigned long more);

int obj_string_patch(struct obj_file *f, int secidx, ElfW(Addr) offset,
		     const char *string);

int obj_symbol_patch(struct obj_file *f, int secidx, ElfW(Addr) offset,
		     struct obj_symbol *sym);

int obj_check_undefineds(struct obj_file *f);

void obj_allocate_commons(struct obj_file *f);

unsigned long obj_load_size (struct obj_file *f);

int obj_relocate (struct obj_file *f, ElfW(Addr) base);

struct obj_file *obj_load(FILE *f);

int obj_create_image (struct obj_file *f, char *image);

/* Architecture specific manipulation routines.  */

struct obj_file *arch_new_file (void);

struct obj_section *arch_new_section (void);

struct obj_symbol *arch_new_symbol (void);

enum obj_reloc arch_apply_relocation (struct obj_file *f,
				      struct obj_section *targsec,
				      struct obj_section *symsec,
				      struct obj_symbol *sym,
				      ElfW(RelM) *rel, ElfW(Addr) value);

int arch_create_got (struct obj_file *f);

struct new_module;
int arch_init_module (struct obj_file *f, struct new_module *);

#endif /* obj.h */
//----------------------------------------------------------------------------
//--------end of modutils obj.h
//----------------------------------------------------------------------------





#define _PATH_MODULES	"/lib/modules"
#define STRVERSIONLEN	32

#if !defined(BB_FEATURE_INSMOD_NEW_KERNEL) && !defined(BB_FEATURE_INSMOD_OLD_KERNEL)
#error "Must have ether BB_FEATURE_INSMOD_NEW_KERNEL or BB_FEATURE_INSMOD_OLD_KERNEL defined"
#endif

/*======================================================================*/

int flag_force_load = 0;
int flag_autoclean = 0;
int flag_verbose = 0;
int flag_export = 1;


/*======================================================================*/

struct i386_got_entry {
	int offset;
	unsigned offset_done:1;
	unsigned reloc_done:1;
};

struct i386_file {
	struct obj_file root;
	struct obj_section *got;
};

struct i386_symbol {
	struct obj_symbol root;
	struct i386_got_entry gotent;
};



struct external_module {
	const char *name;
	ElfW(Addr) addr;
	int used;
	size_t nsyms;
	struct new_module_symbol *syms;
};

struct new_module_symbol *ksyms;
size_t nksyms;

struct external_module *ext_modules;
int n_ext_modules;
int n_ext_modules_used;



/* Some firendly syscalls to cheer everyone's day...  */
#define __NR_new_sys_init_module  __NR_init_module
_syscall2(int, new_sys_init_module, const char *, name,
		  const struct new_module *, info)
#define __NR_old_sys_init_module  __NR_init_module
_syscall5(int, old_sys_init_module, const char *, name, char *, code,
		  unsigned, codesize, struct old_mod_routines *, routines,
		  struct old_symbol_table *, symtab)
_syscall5(int, query_module, const char *, name, int, which,
		void *, buf, size_t, bufsize, size_t*, ret);
#ifndef BB_RMMOD
_syscall1(int, delete_module, const char *, name)
#else
extern int delete_module(const char *);
#endif

#if defined(__i386__) || defined(__m68k__) || defined(__arm__)
/* Jump through hoops to fixup error return codes */
#define __NR__create_module  __NR_create_module
static inline _syscall2(long, _create_module, const char *, name, size_t,
						size)
unsigned long create_module(const char *name, size_t size)
{
	long ret = _create_module(name, size);

	if (ret == -1 && errno > 125) {
		ret = -errno;
		errno = 0;
	}
	return ret;
}
#else
_syscall2(unsigned long, create_module, const char *, name, size_t, size)
#endif
static char m_filename[BUFSIZ + 1] = "\0";
static char m_fullName[BUFSIZ + 1] = "\0";
static const char insmod_usage[] =
	"insmod [OPTION]... MODULE [symbol=value]...\n"
#ifndef BB_FEATURE_TRIVIAL_HELP
	"\nLoads the specified kernel modules into the kernel.\n\n"
	"Options:\n"
	"\t-f\tForce module to load into the wrong kernel version.\n"
	"\t-k\tMake module autoclean-able.\n"
	"\t-v\tverbose output\n" "\t-x\tdo not export externs\n"
#endif
;

/*======================================================================*/

void *xrealloc(void *old, size_t size)
{
	void *ptr = realloc(old, size);
	if (!ptr) {
		perror("Out of memory");
		exit(1);
	}
	return ptr;
}


static int findNamedModule(const char *fileName, struct stat *statbuf,
						   void *userDate)
{
	char *fullName = (char *) userDate;


	if (fullName[0] == '\0')
		return (FALSE);
	else {
		char *tmp = strrchr(fileName, '/');

		if (tmp == NULL)
			tmp = (char *) fileName;
		else
			tmp++;
		if (check_wildcard_match(tmp, fullName) == TRUE) {
			/* Stop searching if we find a match */
			memcpy(m_filename, fileName, strlen(fileName));
			return (FALSE);
		}
	}
	return (TRUE);
}


/*======================================================================*/

struct obj_file *arch_new_file(void)
{
	struct i386_file *f;
	f = xmalloc(sizeof(*f));
	f->got = NULL;
	return &f->root;
}

struct obj_section *arch_new_section(void)
{
	return xmalloc(sizeof(struct obj_section));
}

struct obj_symbol *arch_new_symbol(void)
{
	struct i386_symbol *sym;
	sym = xmalloc(sizeof(*sym));
	memset(&sym->gotent, 0, sizeof(sym->gotent));
	return &sym->root;
}
enum obj_reloc
arch_apply_relocation(struct obj_file *f,
					  struct obj_section *targsec,
					  struct obj_section *symsec,
					  struct obj_symbol *sym,
					  Elf32_Rel * rel, Elf32_Addr v)
{
	struct i386_file *ifile = (struct i386_file *) f;
	struct i386_symbol *isym = (struct i386_symbol *) sym;

	Elf32_Addr *loc = (Elf32_Addr *) (targsec->contents + rel->r_offset);
	Elf32_Addr dot = targsec->header.sh_addr + rel->r_offset;
	Elf32_Addr got = ifile->got ? ifile->got->header.sh_addr : 0;

	enum obj_reloc ret = obj_reloc_ok;

	switch (ELF32_R_TYPE(rel->r_info)) {
	case R_386_NONE:
		break;

	case R_386_32:
		*loc += v;
		break;

	case R_386_PLT32:
	case R_386_PC32:
		*loc += v - dot;
		break;

	case R_386_GLOB_DAT:
	case R_386_JMP_SLOT:
		*loc = v;
		break;

	case R_386_RELATIVE:
		*loc += f->baseaddr;
		break;

	case R_386_GOTPC:
		assert(got != 0);
		*loc += got - dot;
		break;

	case R_386_GOT32:
		assert(isym != NULL);
		if (!isym->gotent.reloc_done) {
			isym->gotent.reloc_done = 1;
			*(Elf32_Addr *) (ifile->got->contents + isym->gotent.offset) =
				v;
		}
		*loc += isym->gotent.offset;
		break;

	case R_386_GOTOFF:
		assert(got != 0);
		*loc += v - got;
		break;

	default:
		ret = obj_reloc_unhandled;
		break;
	}

	return ret;
}

int arch_create_got(struct obj_file *f)
{
	struct i386_file *ifile = (struct i386_file *) f;
	int i, n, offset = 0, gotneeded = 0;

	n = ifile->root.header.e_shnum;
	for (i = 0; i < n; ++i) {
		struct obj_section *relsec, *symsec, *strsec;
		Elf32_Rel *rel, *relend;
		Elf32_Sym *symtab;
		const char *strtab;

		relsec = ifile->root.sections[i];
		if (relsec->header.sh_type != SHT_REL)
			continue;

		symsec = ifile->root.sections[relsec->header.sh_link];
		strsec = ifile->root.sections[symsec->header.sh_link];

		rel = (Elf32_Rel *) relsec->contents;
		relend = rel + (relsec->header.sh_size / sizeof(Elf32_Rel));
		symtab = (Elf32_Sym *) symsec->contents;
		strtab = (const char *) strsec->contents;

		for (; rel < relend; ++rel) {
			Elf32_Sym *extsym;
			struct i386_symbol *intsym;
			const char *name;

			switch (ELF32_R_TYPE(rel->r_info)) {
			case R_386_GOTPC:
			case R_386_GOTOFF:
				gotneeded = 1;
			default:
				continue;

			case R_386_GOT32:
				break;
			}

			extsym = &symtab[ELF32_R_SYM(rel->r_info)];
			if (extsym->st_name)
				name = strtab + extsym->st_name;
			else
				name = f->sections[extsym->st_shndx]->name;
			intsym =
				(struct i386_symbol *) obj_find_symbol(&ifile->root, name);

			if (!intsym->gotent.offset_done) {
				intsym->gotent.offset_done = 1;
				intsym->gotent.offset = offset;
				offset += 4;
			}
		}
	}

	if (offset > 0 || gotneeded)
		ifile->got =
			obj_create_alloced_section(&ifile->root, ".got", 4, offset);

	return 1;
}

int arch_init_module(struct obj_file *f, struct new_module *mod)
{
	return 1;
}


/*======================================================================*/

/* Standard ELF hash function.  */
inline unsigned long obj_elf_hash_n(const char *name, unsigned long n)
{
	unsigned long h = 0;
	unsigned long g;
	unsigned char ch;

	while (n > 0) {
		ch = *name++;
		h = (h << 4) + ch;
		if ((g = (h & 0xf0000000)) != 0) {
			h ^= g >> 24;
			h &= ~g;
		}
		n--;
	}
	return h;
}

unsigned long obj_elf_hash(const char *name)
{
	return obj_elf_hash_n(name, strlen(name));
}

#ifdef BB_FEATURE_INSMOD_VERSION_CHECKING
/* Get the kernel version in the canonical integer form.  */

static int get_kernel_version(char str[STRVERSIONLEN])
{
	struct utsname uts_info;
	char *p, *q;
	int a, b, c;

	if (uname(&uts_info) < 0)
		return -1;
	strncpy(str, uts_info.release, STRVERSIONLEN);
	p = uts_info.release;

	a = strtoul(p, &p, 10);
	if (*p != '.')
		return -1;
	b = strtoul(p + 1, &p, 10);
	if (*p != '.')
		return -1;
	c = strtoul(p + 1, &q, 10);
	if (p + 1 == q)
		return -1;

	return a << 16 | b << 8 | c;
}

/* String comparison for non-co-versioned kernel and module.  */

static int ncv_strcmp(const char *a, const char *b)
{
	size_t alen = strlen(a), blen = strlen(b);

	if (blen == alen + 10 && b[alen] == '_' && b[alen + 1] == 'R')
		return strncmp(a, b, alen);
	else if (alen == blen + 10 && a[blen] == '_' && a[blen + 1] == 'R')
		return strncmp(a, b, blen);
	else
		return strcmp(a, b);
}

/* String hashing for non-co-versioned kernel and module.  Here
   we are simply forced to drop the crc from the hash.  */

static unsigned long ncv_symbol_hash(const char *str)
{
	size_t len = strlen(str);
	if (len > 10 && str[len - 10] == '_' && str[len - 9] == 'R')
		len -= 10;
	return obj_elf_hash_n(str, len);
}

void
obj_set_symbol_compare(struct obj_file *f,
					   int (*cmp) (const char *, const char *),
					   unsigned long (*hash) (const char *))
{
	if (cmp)
		f->symbol_cmp = cmp;
	if (hash) {
		struct obj_symbol *tmptab[HASH_BUCKETS], *sym, *next;
		int i;

		f->symbol_hash = hash;

		memcpy(tmptab, f->symtab, sizeof(tmptab));
		memset(f->symtab, 0, sizeof(f->symtab));

		for (i = 0; i < HASH_BUCKETS; ++i)
			for (sym = tmptab[i]; sym; sym = next) {
				unsigned long h = hash(sym->name) % HASH_BUCKETS;
				next = sym->next;
				sym->next = f->symtab[h];
				f->symtab[h] = sym;
			}
	}
}

#endif							/* BB_FEATURE_INSMOD_VERSION_CHECKING */


struct obj_symbol *obj_add_symbol(struct obj_file *f, const char *name,
								  unsigned long symidx, int info,
								  int secidx, ElfW(Addr) value,
								  unsigned long size)
{
	struct obj_symbol *sym;
	unsigned long hash = f->symbol_hash(name) % HASH_BUCKETS;
	int n_type = ELFW(ST_TYPE) (info);
	int n_binding = ELFW(ST_BIND) (info);

	for (sym = f->symtab[hash]; sym; sym = sym->next)
		if (f->symbol_cmp(sym->name, name) == 0) {
			int o_secidx = sym->secidx;
			int o_info = sym->info;
			int o_type = ELFW(ST_TYPE) (o_info);
			int o_binding = ELFW(ST_BIND) (o_info);

			/* A redefinition!  Is it legal?  */

			if (secidx == SHN_UNDEF)
				return sym;
			else if (o_secidx == SHN_UNDEF)
				goto found;
			else if (n_binding == STB_GLOBAL && o_binding == STB_LOCAL) {
				/* Cope with local and global symbols of the same name
				   in the same object file, as might have been created
				   by ld -r.  The only reason locals are now seen at this
				   level at all is so that we can do semi-sensible things
				   with parameters.  */

				struct obj_symbol *nsym, **p;

				nsym = arch_new_symbol();
				nsym->next = sym->next;
				nsym->ksymidx = -1;

				/* Excise the old (local) symbol from the hash chain.  */
				for (p = &f->symtab[hash]; *p != sym; p = &(*p)->next)
					continue;
				*p = sym = nsym;
				goto found;
			} else if (n_binding == STB_LOCAL) {
				/* Another symbol of the same name has already been defined.
				   Just add this to the local table.  */
				sym = arch_new_symbol();
				sym->next = NULL;
				sym->ksymidx = -1;
				f->local_symtab[symidx] = sym;
				goto found;
			} else if (n_binding == STB_WEAK)
				return sym;
			else if (o_binding == STB_WEAK)
				goto found;
			/* Don't unify COMMON symbols with object types the programmer
			   doesn't expect.  */
			else if (secidx == SHN_COMMON
					 && (o_type == STT_NOTYPE || o_type == STT_OBJECT))
				return sym;
			else if (o_secidx == SHN_COMMON
					 && (n_type == STT_NOTYPE || n_type == STT_OBJECT))
				goto found;
			else {
				/* Don't report an error if the symbol is coming from
				   the kernel or some external module.  */
				if (secidx <= SHN_HIRESERVE)
					fprintf(stderr, "%s multiply defined\n", name);
				return sym;
			}
		}

	/* Completely new symbol.  */
	sym = arch_new_symbol();
	sym->next = f->symtab[hash];
	f->symtab[hash] = sym;
	sym->ksymidx = -1;

	if (ELFW(ST_BIND) (info) == STB_LOCAL)
		f->local_symtab[symidx] = sym;

  found:
	sym->name = name;
	sym->value = value;
	sym->size = size;
	sym->secidx = secidx;
	sym->info = info;

	return sym;
}

struct obj_symbol *obj_find_symbol(struct obj_file *f, const char *name)
{
	struct obj_symbol *sym;
	unsigned long hash = f->symbol_hash(name) % HASH_BUCKETS;

	for (sym = f->symtab[hash]; sym; sym = sym->next)
		if (f->symbol_cmp(sym->name, name) == 0)
			return sym;

	return NULL;
}

ElfW(Addr)
	obj_symbol_final_value(struct obj_file * f, struct obj_symbol * sym)
{
	if (sym) {
		if (sym->secidx >= SHN_LORESERVE)
			return sym->value;

		return sym->value + f->sections[sym->secidx]->header.sh_addr;
	} else {
		/* As a special case, a NULL sym has value zero.  */
		return 0;
	}
}

struct obj_section *obj_find_section(struct obj_file *f, const char *name)
{
	int i, n = f->header.e_shnum;

	for (i = 0; i < n; ++i)
		if (strcmp(f->sections[i]->name, name) == 0)
			return f->sections[i];

	return NULL;
}

static int obj_load_order_prio(struct obj_section *a)
{
	unsigned long af, ac;

	af = a->header.sh_flags;

	ac = 0;
	if (a->name[0] != '.' || strlen(a->name) != 10 ||
		strcmp(a->name + 5, ".init"))
		ac |= 32;
	if (af & SHF_ALLOC)
		ac |= 16;
	if (!(af & SHF_WRITE))
		ac |= 8;
	if (af & SHF_EXECINSTR)
		ac |= 4;
	if (a->header.sh_type != SHT_NOBITS)
		ac |= 2;

	return ac;
}

void
obj_insert_section_load_order(struct obj_file *f, struct obj_section *sec)
{
	struct obj_section **p;
	int prio = obj_load_order_prio(sec);
	for (p = f->load_order_search_start; *p; p = &(*p)->load_next)
		if (obj_load_order_prio(*p) < prio)
			break;
	sec->load_next = *p;
	*p = sec;
}

struct obj_section *obj_create_alloced_section(struct obj_file *f,
											   const char *name,
											   unsigned long align,
											   unsigned long size)
{
	int newidx = f->header.e_shnum++;
	struct obj_section *sec;

	f->sections = xrealloc(f->sections, (newidx + 1) * sizeof(sec));
	f->sections[newidx] = sec = arch_new_section();

	memset(sec, 0, sizeof(*sec));
	sec->header.sh_type = SHT_PROGBITS;
	sec->header.sh_flags = SHF_WRITE | SHF_ALLOC;
	sec->header.sh_size = size;
	sec->header.sh_addralign = align;
	sec->name = name;
	sec->idx = newidx;
	if (size)
		sec->contents = xmalloc(size);

	obj_insert_section_load_order(f, sec);

	return sec;
}

struct obj_section *obj_create_alloced_section_first(struct obj_file *f,
													 const char *name,
													 unsigned long align,
													 unsigned long size)
{
	int newidx = f->header.e_shnum++;
	struct obj_section *sec;

	f->sections = xrealloc(f->sections, (newidx + 1) * sizeof(sec));
	f->sections[newidx] = sec = arch_new_section();

	memset(sec, 0, sizeof(*sec));
	sec->header.sh_type = SHT_PROGBITS;
	sec->header.sh_flags = SHF_WRITE | SHF_ALLOC;
	sec->header.sh_size = size;
	sec->header.sh_addralign = align;
	sec->name = name;
	sec->idx = newidx;
	if (size)
		sec->contents = xmalloc(size);

	sec->load_next = f->load_order;
	f->load_order = sec;
	if (f->load_order_search_start == &f->load_order)
		f->load_order_search_start = &sec->load_next;

	return sec;
}

void *obj_extend_section(struct obj_section *sec, unsigned long more)
{
	unsigned long oldsize = sec->header.sh_size;
	sec->contents = xrealloc(sec->contents, sec->header.sh_size += more);
	return sec->contents + oldsize;
}



/* Conditionally add the symbols from the given symbol set to the
   new module.  */

static int
add_symbols_from(
				 struct obj_file *f,
				 int idx, struct new_module_symbol *syms, size_t nsyms)
{
	struct new_module_symbol *s;
	size_t i;
	int used = 0;

	for (i = 0, s = syms; i < nsyms; ++i, ++s) {

		/* Only add symbols that are already marked external.  If we
		   override locals we may cause problems for argument initialization.
		   We will also create a false dependency on the module.  */
		struct obj_symbol *sym;

		sym = obj_find_symbol(f, (char *) s->name);
		if (sym && !ELFW(ST_BIND) (sym->info) == STB_LOCAL) {
			sym = obj_add_symbol(f, (char *) s->name, -1,
								 ELFW(ST_INFO) (STB_GLOBAL, STT_NOTYPE),
								 idx, s->value, 0);
			/* Did our symbol just get installed?  If so, mark the
			   module as "used".  */
			if (sym->secidx == idx)
				used = 1;
		}
	}

	return used;
}

static void add_kernel_symbols(struct obj_file *f)
{
	struct external_module *m;
	size_t i, nused = 0;

	/* Add module symbols first.  */

	for (i = 0, m = ext_modules; i < n_ext_modules; ++i, ++m)
		if (m->nsyms
			&& add_symbols_from(f, SHN_HIRESERVE + 2 + i, m->syms,
								m->nsyms)) m->used = 1, ++nused;

	n_ext_modules_used = nused;

	/* And finally the symbols from the kernel proper.  */

	if (nksyms)
		add_symbols_from(f, SHN_HIRESERVE + 1, ksyms, nksyms);
}

static char *get_modinfo_value(struct obj_file *f, const char *key)
{
	struct obj_section *sec;
	char *p, *v, *n, *ep;
	size_t klen = strlen(key);

	sec = obj_find_section(f, ".modinfo");
	if (sec == NULL)
		return NULL;
	p = sec->contents;
	ep = p + sec->header.sh_size;
	while (p < ep) {
		v = strchr(p, '=');
		n = strchr(p, '\0');
		if (v) {
			if (v - p == klen && strncmp(p, key, klen) == 0)
				return v + 1;
		} else {
			if (n - p == klen && strcmp(p, key) == 0)
				return n;
		}
		p = n + 1;
	}

	return NULL;
}


/*======================================================================*/
/* Functions relating to module loading in pre 2.1 kernels.  */

static int
old_process_module_arguments(struct obj_file *f, int argc, char **argv)
{
	while (argc > 0) {
		char *p, *q;
		struct obj_symbol *sym;
		int *loc;

		p = *argv;
		if ((q = strchr(p, '=')) == NULL)
			continue;
		*q++ = '\0';

		sym = obj_find_symbol(f, p);

		/* Also check that the parameter was not resolved from the kernel.  */
		if (sym == NULL || sym->secidx > SHN_HIRESERVE) {
			fprintf(stderr, "symbol for parameter %s not found\n", p);
			return 0;
		}

		loc = (int *) (f->sections[sym->secidx]->contents + sym->value);

		/* Do C quoting if we begin with a ".  */
		if (*q == '"') {
			char *r, *str;

			str = alloca(strlen(q));
			for (r = str, q++; *q != '"'; ++q, ++r) {
				if (*q == '\0') {
					fprintf(stderr,
							"improperly terminated string argument for %s\n",
							p);
					return 0;
				} else if (*q == '\\')
					switch (*++q) {
					case 'a':
						*r = '\a';
						break;
					case 'b':
						*r = '\b';
						break;
					case 'e':
						*r = '\033';
						break;
					case 'f':
						*r = '\f';
						break;
					case 'n':
						*r = '\n';
						break;
					case 'r':
						*r = '\r';
						break;
					case 't':
						*r = '\t';
						break;

					case '0':
					case '1':
					case '2':
					case '3':
					case '4':
					case '5':
					case '6':
					case '7':
						{
							int c = *q - '0';
							if (q[1] >= '0' && q[1] <= '7') {
								c = (c * 8) + *++q - '0';
								if (q[1] >= '0' && q[1] <= '7')
									c = (c * 8) + *++q - '0';
							}
							*r = c;
						}
						break;

					default:
						*r = *q;
						break;
				} else
					*r = *q;
			}
			*r = '\0';
			obj_string_patch(f, sym->secidx, sym->value, str);
		} else if (*q >= '0' && *q <= '9') {
			do
				*loc++ = strtoul(q, &q, 0);
			while (*q++ == ',');
		} else {
			char *contents = f->sections[sym->secidx]->contents;
			char *loc = contents + sym->value;
			char *r;			/* To search for commas */

			/* Break the string with comas */
			while ((r = strchr(q, ',')) != (char *) NULL) {
				*r++ = '\0';
				obj_string_patch(f, sym->secidx, loc - contents, q);
				loc += sizeof(char *);
				q = r;
			}

			/* last part */
			obj_string_patch(f, sym->secidx, loc - contents, q);
		}

		argc--, argv++;
	}

	return 1;
}

#ifdef BB_FEATURE_INSMOD_VERSION_CHECKING
static int old_is_module_checksummed(struct obj_file *f)
{
	return obj_find_symbol(f, "Using_Versions") != NULL;
}
/* Get the module's kernel version in the canonical integer form.  */

static int
old_get_module_version(struct obj_file *f, char str[STRVERSIONLEN])
{
	struct obj_symbol *sym;
	char *p, *q;
	int a, b, c;

	sym = obj_find_symbol(f, "kernel_version");
	if (sym == NULL)
		return -1;

	p = f->sections[sym->secidx]->contents + sym->value;
	strncpy(str, p, STRVERSIONLEN);

	a = strtoul(p, &p, 10);
	if (*p != '.')
		return -1;
	b = strtoul(p + 1, &p, 10);
	if (*p != '.')
		return -1;
	c = strtoul(p + 1, &q, 10);
	if (p + 1 == q)
		return -1;

	return a << 16 | b << 8 | c;
}

#endif   /* BB_FEATURE_INSMOD_VERSION_CHECKING */

#ifdef BB_FEATURE_INSMOD_OLD_KERNEL

/* Fetch all the symbols and divvy them up as appropriate for the modules.  */

static int old_get_kernel_symbols(void)
{
	struct old_kernel_sym *ks, *k;
	struct new_module_symbol *s;
	struct external_module *mod;
	int nks, nms, nmod, i;

	nks = get_kernel_syms(NULL);
	if (nks < 0) {
		perror("get_kernel_syms: %m");
		return 0;
	}

	ks = k = xmalloc(nks * sizeof(*ks));

	if (get_kernel_syms(ks) != nks) {
		perror("inconsistency with get_kernel_syms -- is someone else "
			   "playing with modules?");
		free(ks);
		return 0;
	}

	/* Collect the module information.  */

	mod = NULL;
	nmod = -1;

	while (k->name[0] == '#' && k->name[1]) {
		struct old_kernel_sym *k2;
		struct new_module_symbol *s;

		/* Find out how many symbols this module has.  */
		for (k2 = k + 1; k2->name[0] != '#'; ++k2)
			continue;
		nms = k2 - k - 1;

		mod = xrealloc(mod, (++nmod + 1) * sizeof(*mod));
		mod[nmod].name = k->name + 1;
		mod[nmod].addr = k->value;
		mod[nmod].used = 0;
		mod[nmod].nsyms = nms;
		mod[nmod].syms = s = (nms ? xmalloc(nms * sizeof(*s)) : NULL);

		for (i = 0, ++k; i < nms; ++i, ++s, ++k) {
			s->name = (unsigned long) k->name;
			s->value = k->value;
		}

		k = k2;
	}

	ext_modules = mod;
	n_ext_modules = nmod + 1;

	/* Now collect the symbols for the kernel proper.  */

	if (k->name[0] == '#')
		++k;

	nksyms = nms = nks - (k - ks);
	ksyms = s = (nms ? xmalloc(nms * sizeof(*s)) : NULL);

	for (i = 0; i < nms; ++i, ++s, ++k) {
		s->name = (unsigned long) k->name;
		s->value = k->value;
	}

	return 1;
}

/* Return the kernel symbol checksum version, or zero if not used.  */

static int old_is_kernel_checksummed(void)
{
	/* Using_Versions is the first symbol.  */
	if (nksyms > 0
		&& strcmp((char *) ksyms[0].name,
				  "Using_Versions") == 0) return ksyms[0].value;
	else
		return 0;
}


static int old_create_mod_use_count(struct obj_file *f)
{
	struct obj_section *sec;

	sec = obj_create_alloced_section_first(f, ".moduse", sizeof(long),
										   sizeof(long));

	obj_add_symbol(f, "mod_use_count_", -1,
				   ELFW(ST_INFO) (STB_LOCAL, STT_OBJECT), sec->idx, 0,
				   sizeof(long));

	return 1;
}

static int
old_init_module(const char *m_name, struct obj_file *f,
				unsigned long m_size)
{
	char *image;
	struct old_mod_routines routines;
	struct old_symbol_table *symtab;
	int ret;

	/* Create the symbol table */
	{
		int nsyms = 0, strsize = 0, total;

		/* Size things first... */
		if (flag_export) {
			int i;
			for (i = 0; i < HASH_BUCKETS; ++i) {
				struct obj_symbol *sym;
				for (sym = f->symtab[i]; sym; sym = sym->next)
					if (ELFW(ST_BIND) (sym->info) != STB_LOCAL
						&& sym->secidx <= SHN_HIRESERVE) 
					{
						sym->ksymidx = nsyms++;
						strsize += strlen(sym->name) + 1;
					}
			}
		}

		total = (sizeof(struct old_symbol_table)
				 + nsyms * sizeof(struct old_module_symbol)
				 + n_ext_modules_used * sizeof(struct old_module_ref)
				 + strsize);
		symtab = xmalloc(total);
		symtab->size = total;
		symtab->n_symbols = nsyms;
		symtab->n_refs = n_ext_modules_used;

		if (flag_export && nsyms) {
			struct old_module_symbol *ksym;
			char *str;
			int i;

			ksym = symtab->symbol;
			str = ((char *) ksym + nsyms * sizeof(struct old_module_symbol)
				   + n_ext_modules_used * sizeof(struct old_module_ref));

			for (i = 0; i < HASH_BUCKETS; ++i) {
				struct obj_symbol *sym;
				for (sym = f->symtab[i]; sym; sym = sym->next)
					if (sym->ksymidx >= 0) {
						ksym->addr = obj_symbol_final_value(f, sym);
						ksym->name =
							(unsigned long) str - (unsigned long) symtab;

						str = stpcpy(str, sym->name) + 1;
						ksym++;
					}
			}
		}

		if (n_ext_modules_used) {
			struct old_module_ref *ref;
			int i;

			ref = (struct old_module_ref *)
				((char *) symtab->symbol + nsyms * sizeof(struct old_module_symbol));

			for (i = 0; i < n_ext_modules; ++i)
				if (ext_modules[i].used)
					ref++->module = ext_modules[i].addr;
		}
	}

	/* Fill in routines.  */

	routines.init =
		obj_symbol_final_value(f, obj_find_symbol(f, "init_module"));
	routines.cleanup =
		obj_symbol_final_value(f, obj_find_symbol(f, "cleanup_module"));

	/* Whew!  All of the initialization is complete.  Collect the final
	   module image and give it to the kernel.  */

	image = xmalloc(m_size);
	obj_create_image(f, image);

	/* image holds the complete relocated module, accounting correctly for
	   mod_use_count.  However the old module kernel support assume that
	   it is receiving something which does not contain mod_use_count.  */
	ret = old_sys_init_module(m_name, image + sizeof(long),
							  m_size | (flag_autoclean ? OLD_MOD_AUTOCLEAN
										: 0), &routines, symtab);
	if (ret)
		perror("init_module: %m");

	free(image);
	free(symtab);

	return ret == 0;
}

#else

#define old_create_mod_use_count(x) TRUE
#define old_init_module(x, y, z) TRUE

#endif							/* BB_FEATURE_INSMOD_OLD_KERNEL */



/*======================================================================*/
/* Functions relating to module loading after 2.1.18.  */

static int
new_process_module_arguments(struct obj_file *f, int argc, char **argv)
{
	while (argc > 0) {
		char *p, *q, *key;
		struct obj_symbol *sym;
		char *contents, *loc;
		int min, max, n;

		p = *argv;
		if ((q = strchr(p, '=')) == NULL)
			continue;

		key = alloca(q - p + 6);
		memcpy(key, "parm_", 5);
		memcpy(key + 5, p, q - p);
		key[q - p + 5] = 0;

		p = get_modinfo_value(f, key);
		key += 5;
		if (p == NULL) {
			fprintf(stderr, "invalid parameter %s\n", key);
			return 0;
		}

		sym = obj_find_symbol(f, key);

		/* Also check that the parameter was not resolved from the kernel.  */
		if (sym == NULL || sym->secidx > SHN_HIRESERVE) {
			fprintf(stderr, "symbol for parameter %s not found\n", key);
			return 0;
		}

		if (isdigit(*p)) {
			min = strtoul(p, &p, 10);
			if (*p == '-')
				max = strtoul(p + 1, &p, 10);
			else
				max = min;
		} else
			min = max = 1;

		contents = f->sections[sym->secidx]->contents;
		loc = contents + sym->value;
		n = (*++q != '\0');

		while (1) {
			if ((*p == 's') || (*p == 'c')) {
				char *str;

				/* Do C quoting if we begin with a ", else slurp the lot.  */
				if (*q == '"') {
					char *r;

					str = alloca(strlen(q));
					for (r = str, q++; *q != '"'; ++q, ++r) {
						if (*q == '\0') {
							fprintf(stderr,
									"improperly terminated string argument for %s\n",
									key);
							return 0;
						} else if (*q == '\\')
							switch (*++q) {
							case 'a':
								*r = '\a';
								break;
							case 'b':
								*r = '\b';
								break;
							case 'e':
								*r = '\033';
								break;
							case 'f':
								*r = '\f';
								break;
							case 'n':
								*r = '\n';
								break;
							case 'r':
								*r = '\r';
								break;
							case 't':
								*r = '\t';
								break;

							case '0':
							case '1':
							case '2':
							case '3':
							case '4':
							case '5':
							case '6':
							case '7':
								{
									int c = *q - '0';
									if (q[1] >= '0' && q[1] <= '7') {
										c = (c * 8) + *++q - '0';
										if (q[1] >= '0' && q[1] <= '7')
											c = (c * 8) + *++q - '0';
									}
									*r = c;
								}
								break;

							default:
								*r = *q;
								break;
						} else
							*r = *q;
					}
					*r = '\0';
					++q;
				} else {
					char *r;

					/* In this case, the string is not quoted. We will break
					   it using the coma (like for ints). If the user wants to
					   include comas in a string, he just has to quote it */

					/* Search the next coma */
					r = strchr(q, ',');

					/* Found ? */
					if (r != (char *) NULL) {
						/* Recopy the current field */
						str = alloca(r - q + 1);
						memcpy(str, q, r - q);

						/* I don't know if it is usefull, as the previous case
						   doesn't null terminate the string ??? */
						str[r - q] = '\0';

						/* Keep next fields */
						q = r;
					} else {
						/* last string */
						str = q;
						q = "";
					}
				}

				if (*p == 's') {
					/* Normal string */
					obj_string_patch(f, sym->secidx, loc - contents, str);
					loc += tgt_sizeof_char_p;
				} else {
					/* Array of chars (in fact, matrix !) */
					long charssize;	/* size of each member */

					/* Get the size of each member */
					/* Probably we should do that outside the loop ? */
					if (!isdigit(*(p + 1))) {
						fprintf(stderr,
								"parameter type 'c' for %s must be followed by"
								" the maximum size\n", key);
						return 0;
					}
					charssize = strtoul(p + 1, (char **) NULL, 10);

					/* Check length */
					if (strlen(str) >= charssize) {
						fprintf(stderr,
								"string too long for %s (max %ld)\n", key,
								charssize - 1);
						return 0;
					}

					/* Copy to location */
					strcpy((char *) loc, str);
					loc += charssize;
				}
			} else {
				long v = strtoul(q, &q, 0);
				switch (*p) {
				case 'b':
					*loc++ = v;
					break;
				case 'h':
					*(short *) loc = v;
					loc += tgt_sizeof_short;
					break;
				case 'i':
					*(int *) loc = v;
					loc += tgt_sizeof_int;
					break;
				case 'l':
					*(long *) loc = v;
					loc += tgt_sizeof_long;
					break;

				default:
					fprintf(stderr, "unknown parameter type '%c' for %s\n",
							*p, key);
					return 0;
				}
			}

		  retry_end_of_value:
			switch (*q) {
			case '\0':
				goto end_of_arg;

			case ' ':
			case '\t':
			case '\n':
			case '\r':
				++q;
				goto retry_end_of_value;

			case ',':
				if (++n > max) {
					fprintf(stderr, "too many values for %s (max %d)\n",
							key, max);
					return 0;
				}
				++q;
				break;

			default:
				fprintf(stderr, "invalid argument syntax for %s\n", key);
				return 0;
			}
		}

	  end_of_arg:
		if (n < min) {
			fprintf(stderr, "too few values for %s (min %d)\n", key, min);
			return 0;
		}

		argc--, argv++;
	}

	return 1;
}

#ifdef BB_FEATURE_INSMOD_VERSION_CHECKING
static int new_is_module_checksummed(struct obj_file *f)
{
	const char *p = get_modinfo_value(f, "using_checksums");
	if (p)
		return atoi(p);
	else
		return 0;
}

/* Get the module's kernel version in the canonical integer form.  */

static int
new_get_module_version(struct obj_file *f, char str[STRVERSIONLEN])
{
	char *p, *q;
	int a, b, c;

	p = get_modinfo_value(f, "kernel_version");
	if (p == NULL)
		return -1;
	strncpy(str, p, STRVERSIONLEN);

	a = strtoul(p, &p, 10);
	if (*p != '.')
		return -1;
	b = strtoul(p + 1, &p, 10);
	if (*p != '.')
		return -1;
	c = strtoul(p + 1, &q, 10);
	if (p + 1 == q)
		return -1;

	return a << 16 | b << 8 | c;
}

#endif   /* BB_FEATURE_INSMOD_VERSION_CHECKING */


#ifdef BB_FEATURE_INSMOD_NEW_KERNEL

/* Fetch the loaded modules, and all currently exported symbols.  */

static int new_get_kernel_symbols(void)
{
	char *module_names, *mn;
	struct external_module *modules, *m;
	struct new_module_symbol *syms, *s;
	size_t ret, bufsize, nmod, nsyms, i, j;

	/* Collect the loaded modules.  */

	module_names = xmalloc(bufsize = 256);
  retry_modules_load:
	if (query_module(NULL, QM_MODULES, module_names, bufsize, &ret)) {
		if (errno == ENOSPC) {
			module_names = xrealloc(module_names, bufsize = ret);
			goto retry_modules_load;
		}
		perror("QM_MODULES: %m\n");
		return 0;
	}

	n_ext_modules = nmod = ret;
	ext_modules = modules = xmalloc(nmod * sizeof(*modules));
	memset(modules, 0, nmod * sizeof(*modules));

	/* Collect the modules' symbols.  */

	for (i = 0, mn = module_names, m = modules;
		 i < nmod; ++i, ++m, mn += strlen(mn) + 1) {
		struct new_module_info info;

		if (query_module(mn, QM_INFO, &info, sizeof(info), &ret)) {
			if (errno == ENOENT) {
				/* The module was removed out from underneath us.  */
				continue;
			}
			perror("query_module: QM_INFO: %m");
			return 0;
		}

		syms = xmalloc(bufsize = 1024);
	  retry_mod_sym_load:
		if (query_module(mn, QM_SYMBOLS, syms, bufsize, &ret)) {
			switch (errno) {
			case ENOSPC:
				syms = xrealloc(syms, bufsize = ret);
				goto retry_mod_sym_load;
			case ENOENT:
				/* The module was removed out from underneath us.  */
				continue;
			default:
				perror("query_module: QM_SYMBOLS: %m");
				return 0;
			}
		}
		nsyms = ret;

		m->name = mn;
		m->addr = info.addr;
		m->nsyms = nsyms;
		m->syms = syms;

		for (j = 0, s = syms; j < nsyms; ++j, ++s) {
			s->name += (unsigned long) syms;
		}
	}

	/* Collect the kernel's symbols.  */

	syms = xmalloc(bufsize = 16 * 1024);
  retry_kern_sym_load:
	if (query_module(NULL, QM_SYMBOLS, syms, bufsize, &ret)) {
		if (errno == ENOSPC) {
			syms = xrealloc(syms, bufsize = ret);
			goto retry_kern_sym_load;
		}
		perror("kernel: QM_SYMBOLS: %m");
		return 0;
	}
	nksyms = nsyms = ret;
	ksyms = syms;

	for (j = 0, s = syms; j < nsyms; ++j, ++s) {
		s->name += (unsigned long) syms;
	}
	return 1;
}


/* Return the kernel symbol checksum version, or zero if not used.  */

static int new_is_kernel_checksummed(void)
{
	struct new_module_symbol *s;
	size_t i;

	/* Using_Versions is not the first symbol, but it should be in there.  */

	for (i = 0, s = ksyms; i < nksyms; ++i, ++s)
		if (strcmp((char *) s->name, "Using_Versions") == 0)
			return s->value;

	return 0;
}


static int new_create_this_module(struct obj_file *f, const char *m_name)
{
	struct obj_section *sec;

	sec = obj_create_alloced_section_first(f, ".this", tgt_sizeof_long,
										   sizeof(struct new_module));
	memset(sec->contents, 0, sizeof(struct new_module));

	obj_add_symbol(f, "__this_module", -1,
				   ELFW(ST_INFO) (STB_LOCAL, STT_OBJECT), sec->idx, 0,
				   sizeof(struct new_module));

	obj_string_patch(f, sec->idx, offsetof(struct new_module, name),
					 m_name);

	return 1;
}


static int new_create_module_ksymtab(struct obj_file *f)
{
	struct obj_section *sec;
	int i;

	/* We must always add the module references.  */

	if (n_ext_modules_used) {
		struct new_module_ref *dep;
		struct obj_symbol *tm;

		sec = obj_create_alloced_section(f, ".kmodtab", tgt_sizeof_void_p,
										 (sizeof(struct new_module_ref)
										  * n_ext_modules_used));
		if (!sec)
			return 0;

		tm = obj_find_symbol(f, "__this_module");
		dep = (struct new_module_ref *) sec->contents;
		for (i = 0; i < n_ext_modules; ++i)
			if (ext_modules[i].used) {
				dep->dep = ext_modules[i].addr;
				obj_symbol_patch(f, sec->idx,
								 (char *) &dep->ref - sec->contents, tm);
				dep->next_ref = 0;
				++dep;
			}
	}

	if (flag_export && !obj_find_section(f, "__ksymtab")) {
		size_t nsyms;
		int *loaded;

		sec =
			obj_create_alloced_section(f, "__ksymtab", tgt_sizeof_void_p,
									   0);

		/* We don't want to export symbols residing in sections that
		   aren't loaded.  There are a number of these created so that
		   we make sure certain module options don't appear twice.  */

		loaded = alloca(sizeof(int) * (i = f->header.e_shnum));
		while (--i >= 0)
			loaded[i] = (f->sections[i]->header.sh_flags & SHF_ALLOC) != 0;

		for (nsyms = i = 0; i < HASH_BUCKETS; ++i) {
			struct obj_symbol *sym;
			for (sym = f->symtab[i]; sym; sym = sym->next)
				if (ELFW(ST_BIND) (sym->info) != STB_LOCAL
					&& sym->secidx <= SHN_HIRESERVE
					&& (sym->secidx >= SHN_LORESERVE
						|| loaded[sym->secidx])) {
					ElfW(Addr) ofs = nsyms * 2 * tgt_sizeof_void_p;

					obj_symbol_patch(f, sec->idx, ofs, sym);
					obj_string_patch(f, sec->idx, ofs + tgt_sizeof_void_p,
									 sym->name);

					nsyms++;
				}
		}

		obj_extend_section(sec, nsyms * 2 * tgt_sizeof_char_p);
	}

	return 1;
}


static int
new_init_module(const char *m_name, struct obj_file *f,
				unsigned long m_size)
{
	struct new_module *module;
	struct obj_section *sec;
	void *image;
	int ret;
	tgt_long m_addr;

	sec = obj_find_section(f, ".this");
	module = (struct new_module *) sec->contents;
	m_addr = sec->header.sh_addr;

	module->size_of_struct = sizeof(*module);
	module->size = m_size;
	module->flags = flag_autoclean ? NEW_MOD_AUTOCLEAN : 0;

	sec = obj_find_section(f, "__ksymtab");
	if (sec && sec->header.sh_size) {
		module->syms = sec->header.sh_addr;
		module->nsyms = sec->header.sh_size / (2 * tgt_sizeof_char_p);
	}

	if (n_ext_modules_used) {
		sec = obj_find_section(f, ".kmodtab");
		module->deps = sec->header.sh_addr;
		module->ndeps = n_ext_modules_used;
	}

	module->init =
		obj_symbol_final_value(f, obj_find_symbol(f, "init_module"));
	module->cleanup =
		obj_symbol_final_value(f, obj_find_symbol(f, "cleanup_module"));

	sec = obj_find_section(f, "__ex_table");
	if (sec) {
		module->ex_table_start = sec->header.sh_addr;
		module->ex_table_end = sec->header.sh_addr + sec->header.sh_size;
	}

	sec = obj_find_section(f, ".text.init");
	if (sec) {
		module->runsize = sec->header.sh_addr - m_addr;
	}
	sec = obj_find_section(f, ".data.init");
	if (sec) {
		if (!module->runsize ||
			module->runsize > sec->header.sh_addr - m_addr)
				module->runsize = sec->header.sh_addr - m_addr;
	}

	if (!arch_init_module(f, module))
		return 0;

	/* Whew!  All of the initialization is complete.  Collect the final
	   module image and give it to the kernel.  */

	image = xmalloc(m_size);
	obj_create_image(f, image);

	ret = new_sys_init_module(m_name, (struct new_module *) image);
	if (ret)
		perror("init_module: %m");

	free(image);

	return ret == 0;
}

#else

#define new_init_module(x, y, z) TRUE
#define new_create_this_module(x, y) 0
#define new_create_module_ksymtab(x)

#endif							/* BB_FEATURE_INSMOD_OLD_KERNEL */


/*======================================================================*/

int
obj_string_patch(struct obj_file *f, int secidx, ElfW(Addr) offset,
				 const char *string)
{
	struct obj_string_patch *p;
	struct obj_section *strsec;
	size_t len = strlen(string) + 1;
	char *loc;

	p = xmalloc(sizeof(*p));
	p->next = f->string_patches;
	p->reloc_secidx = secidx;
	p->reloc_offset = offset;
	f->string_patches = p;

	strsec = obj_find_section(f, ".kstrtab");
	if (strsec == NULL) {
		strsec = obj_create_alloced_section(f, ".kstrtab", 1, len);
		p->string_offset = 0;
		loc = strsec->contents;
	} else {
		p->string_offset = strsec->header.sh_size;
		loc = obj_extend_section(strsec, len);
	}
	memcpy(loc, string, len);

	return 1;
}

int
obj_symbol_patch(struct obj_file *f, int secidx, ElfW(Addr) offset,
				 struct obj_symbol *sym)
{
	struct obj_symbol_patch *p;

	p = xmalloc(sizeof(*p));
	p->next = f->symbol_patches;
	p->reloc_secidx = secidx;
	p->reloc_offset = offset;
	p->sym = sym;
	f->symbol_patches = p;

	return 1;
}

int obj_check_undefineds(struct obj_file *f)
{
	unsigned long i;
	int ret = 1;

	for (i = 0; i < HASH_BUCKETS; ++i) {
		struct obj_symbol *sym;
		for (sym = f->symtab[i]; sym; sym = sym->next)
			if (sym->secidx == SHN_UNDEF) {
				if (ELFW(ST_BIND) (sym->info) == STB_WEAK) {
					sym->secidx = SHN_ABS;
					sym->value = 0;
				} else {
					fprintf(stderr, "unresolved symbol %s\n", sym->name);
					ret = 0;
				}
			}
	}

	return ret;
}

void obj_allocate_commons(struct obj_file *f)
{
	struct common_entry {
		struct common_entry *next;
		struct obj_symbol *sym;
	} *common_head = NULL;

	unsigned long i;

	for (i = 0; i < HASH_BUCKETS; ++i) {
		struct obj_symbol *sym;
		for (sym = f->symtab[i]; sym; sym = sym->next)
			if (sym->secidx == SHN_COMMON) {
				/* Collect all COMMON symbols and sort them by size so as to
				   minimize space wasted by alignment requirements.  */
				{
					struct common_entry **p, *n;
					for (p = &common_head; *p; p = &(*p)->next)
						if (sym->size <= (*p)->sym->size)
							break;

					n = alloca(sizeof(*n));
					n->next = *p;
					n->sym = sym;
					*p = n;
				}
			}
	}

	for (i = 1; i < f->local_symtab_size; ++i) {
		struct obj_symbol *sym = f->local_symtab[i];
		if (sym && sym->secidx == SHN_COMMON) {
			struct common_entry **p, *n;
			for (p = &common_head; *p; p = &(*p)->next)
				if (sym == (*p)->sym)
					break;
				else if (sym->size < (*p)->sym->size) {
					n = alloca(sizeof(*n));
					n->next = *p;
					n->sym = sym;
					*p = n;
					break;
				}
		}
	}

	if (common_head) {
		/* Find the bss section.  */
		for (i = 0; i < f->header.e_shnum; ++i)
			if (f->sections[i]->header.sh_type == SHT_NOBITS)
				break;

		/* If for some reason there hadn't been one, create one.  */
		if (i == f->header.e_shnum) {
			struct obj_section *sec;

			f->sections = xrealloc(f->sections, (i + 1) * sizeof(sec));
			f->sections[i] = sec = arch_new_section();
			f->header.e_shnum = i + 1;

			memset(sec, 0, sizeof(*sec));
			sec->header.sh_type = SHT_PROGBITS;
			sec->header.sh_flags = SHF_WRITE | SHF_ALLOC;
			sec->name = ".bss";
			sec->idx = i;
		}

		/* Allocate the COMMONS.  */
		{
			ElfW(Addr) bss_size = f->sections[i]->header.sh_size;
			ElfW(Addr) max_align = f->sections[i]->header.sh_addralign;
			struct common_entry *c;

			for (c = common_head; c; c = c->next) {
				ElfW(Addr) align = c->sym->value;

				if (align > max_align)
					max_align = align;
				if (bss_size & (align - 1))
					bss_size = (bss_size | (align - 1)) + 1;

				c->sym->secidx = i;
				c->sym->value = bss_size;

				bss_size += c->sym->size;
			}

			f->sections[i]->header.sh_size = bss_size;
			f->sections[i]->header.sh_addralign = max_align;
		}
	}

	/* For the sake of patch relocation and parameter initialization,
	   allocate zeroed data for NOBITS sections now.  Note that after
	   this we cannot assume NOBITS are really empty.  */
	for (i = 0; i < f->header.e_shnum; ++i) {
		struct obj_section *s = f->sections[i];
		if (s->header.sh_type == SHT_NOBITS) {
			s->contents = memset(xmalloc(s->header.sh_size),
								 0, s->header.sh_size);
			s->header.sh_type = SHT_PROGBITS;
		}
	}
}

unsigned long obj_load_size(struct obj_file *f)
{
	unsigned long dot = 0;
	struct obj_section *sec;

	/* Finalize the positions of the sections relative to one another.  */

	for (sec = f->load_order; sec; sec = sec->load_next) {
		ElfW(Addr) align;

		align = sec->header.sh_addralign;
		if (align && (dot & (align - 1)))
			dot = (dot | (align - 1)) + 1;

		sec->header.sh_addr = dot;
		dot += sec->header.sh_size;
	}

	return dot;
}

int obj_relocate(struct obj_file *f, ElfW(Addr) base)
{
	int i, n = f->header.e_shnum;
	int ret = 1;

	/* Finalize the addresses of the sections.  */

	f->baseaddr = base;
	for (i = 0; i < n; ++i)
		f->sections[i]->header.sh_addr += base;

	/* And iterate over all of the relocations.  */

	for (i = 0; i < n; ++i) {
		struct obj_section *relsec, *symsec, *targsec, *strsec;
		ElfW(RelM) * rel, *relend;
		ElfW(Sym) * symtab;
		const char *strtab;

		relsec = f->sections[i];
		if (relsec->header.sh_type != SHT_RELM)
			continue;

		symsec = f->sections[relsec->header.sh_link];
		targsec = f->sections[relsec->header.sh_info];
		strsec = f->sections[symsec->header.sh_link];

		rel = (ElfW(RelM) *) relsec->contents;
		relend = rel + (relsec->header.sh_size / sizeof(ElfW(RelM)));
		symtab = (ElfW(Sym) *) symsec->contents;
		strtab = (const char *) strsec->contents;

		for (; rel < relend; ++rel) {
			ElfW(Addr) value = 0;
			struct obj_symbol *intsym = NULL;
			unsigned long symndx;
			ElfW(Sym) * extsym = 0;
			const char *errmsg;

			/* Attempt to find a value to use for this relocation.  */

			symndx = ELFW(R_SYM) (rel->r_info);
			if (symndx) {
				/* Note we've already checked for undefined symbols.  */

				extsym = &symtab[symndx];
				if (ELFW(ST_BIND) (extsym->st_info) == STB_LOCAL) {
					/* Local symbols we look up in the local table to be sure
					   we get the one that is really intended.  */
					intsym = f->local_symtab[symndx];
				} else {
					/* Others we look up in the hash table.  */
					const char *name;
					if (extsym->st_name)
						name = strtab + extsym->st_name;
					else
						name = f->sections[extsym->st_shndx]->name;
					intsym = obj_find_symbol(f, name);
				}

				value = obj_symbol_final_value(f, intsym);
				intsym->referenced = 1;
			}
#if SHT_RELM == SHT_RELA
#if defined(__alpha__) && defined(AXP_BROKEN_GAS)
			/* Work around a nasty GAS bug, that is fixed as of 2.7.0.9.  */
			if (!extsym || !extsym->st_name ||
				ELFW(ST_BIND) (extsym->st_info) != STB_LOCAL)
#endif
				value += rel->r_addend;
#endif

			/* Do it! */
			switch (arch_apply_relocation
					(f, targsec, symsec, intsym, rel, value)) {
			case obj_reloc_ok:
				break;

			case obj_reloc_overflow:
				errmsg = "Relocation overflow";
				goto bad_reloc;
			case obj_reloc_dangerous:
				errmsg = "Dangerous relocation";
				goto bad_reloc;
			case obj_reloc_unhandled:
				errmsg = "Unhandled relocation";
			  bad_reloc:
				if (extsym) {
					fprintf(stderr, "%s of type %ld for %s\n", errmsg,
							(long) ELFW(R_TYPE) (rel->r_info),
							strtab + extsym->st_name);
				} else {
					fprintf(stderr, "%s of type %ld\n", errmsg,
							(long) ELFW(R_TYPE) (rel->r_info));
				}
				ret = 0;
				break;
			}
		}
	}

	/* Finally, take care of the patches.  */

	if (f->string_patches) {
		struct obj_string_patch *p;
		struct obj_section *strsec;
		ElfW(Addr) strsec_base;
		strsec = obj_find_section(f, ".kstrtab");
		strsec_base = strsec->header.sh_addr;

		for (p = f->string_patches; p; p = p->next) {
			struct obj_section *targsec = f->sections[p->reloc_secidx];
			*(ElfW(Addr) *) (targsec->contents + p->reloc_offset)
				= strsec_base + p->string_offset;
		}
	}

	if (f->symbol_patches) {
		struct obj_symbol_patch *p;

		for (p = f->symbol_patches; p; p = p->next) {
			struct obj_section *targsec = f->sections[p->reloc_secidx];
			*(ElfW(Addr) *) (targsec->contents + p->reloc_offset)
				= obj_symbol_final_value(f, p->sym);
		}
	}

	return ret;
}

int obj_create_image(struct obj_file *f, char *image)
{
	struct obj_section *sec;
	ElfW(Addr) base = f->baseaddr;

	for (sec = f->load_order; sec; sec = sec->load_next) {
		char *secimg;

		if (sec->header.sh_size == 0)
			continue;

		secimg = image + (sec->header.sh_addr - base);

		/* Note that we allocated data for NOBITS sections earlier.  */
		memcpy(secimg, sec->contents, sec->header.sh_size);
	}

	return 1;
}

/*======================================================================*/

struct obj_file *obj_load(FILE * fp)
{
	struct obj_file *f;
	ElfW(Shdr) * section_headers;
	int shnum, i;
	char *shstrtab;

	/* Read the file header.  */

	f = arch_new_file();
	memset(f, 0, sizeof(*f));
	f->symbol_cmp = strcmp;
	f->symbol_hash = obj_elf_hash;
	f->load_order_search_start = &f->load_order;

	fseek(fp, 0, SEEK_SET);
	if (fread(&f->header, sizeof(f->header), 1, fp) != 1) {
		perror("error reading ELF header: %m");
		return NULL;
	}

	if (f->header.e_ident[EI_MAG0] != ELFMAG0
		|| f->header.e_ident[EI_MAG1] != ELFMAG1
		|| f->header.e_ident[EI_MAG2] != ELFMAG2
		|| f->header.e_ident[EI_MAG3] != ELFMAG3) {
		fprintf(stderr, "not an ELF file\n");
		return NULL;
	}
	if (f->header.e_ident[EI_CLASS] != ELFCLASSM
		|| f->header.e_ident[EI_DATA] != ELFDATAM
		|| f->header.e_ident[EI_VERSION] != EV_CURRENT
		|| !MATCH_MACHINE(f->header.e_machine)) {
		fprintf(stderr, "ELF file not for this architecture\n");
		return NULL;
	}
	if (f->header.e_type != ET_REL) {
		fprintf(stderr, "ELF file not a relocatable object\n");
		return NULL;
	}

	/* Read the section headers.  */

	if (f->header.e_shentsize != sizeof(ElfW(Shdr))) {
		fprintf(stderr, "section header size mismatch: %lu != %lu\n",
				(unsigned long) f->header.e_shentsize,
				(unsigned long) sizeof(ElfW(Shdr)));
		return NULL;
	}

	shnum = f->header.e_shnum;
	f->sections = xmalloc(sizeof(struct obj_section *) * shnum);
	memset(f->sections, 0, sizeof(struct obj_section *) * shnum);

	section_headers = alloca(sizeof(ElfW(Shdr)) * shnum);
	fseek(fp, f->header.e_shoff, SEEK_SET);
	if (fread(section_headers, sizeof(ElfW(Shdr)), shnum, fp) != shnum) {
		perror("error reading ELF section headers: %m");
		return NULL;
	}

	/* Read the section data.  */

	for (i = 0; i < shnum; ++i) {
		struct obj_section *sec;

		f->sections[i] = sec = arch_new_section();
		memset(sec, 0, sizeof(*sec));

		sec->header = section_headers[i];
		sec->idx = i;

		switch (sec->header.sh_type) {
		case SHT_NULL:
		case SHT_NOTE:
		case SHT_NOBITS:
			/* ignore */
			break;

		case SHT_PROGBITS:
		case SHT_SYMTAB:
		case SHT_STRTAB:
		case SHT_RELM:
			if (sec->header.sh_size > 0) {
				sec->contents = xmalloc(sec->header.sh_size);
				fseek(fp, sec->header.sh_offset, SEEK_SET);
				if (fread(sec->contents, sec->header.sh_size, 1, fp) != 1) {
					fprintf(stderr,
							"error reading ELF section data: %m\n");
					return NULL;
				}
			} else {
				sec->contents = NULL;
			}
			break;

#if SHT_RELM == SHT_REL
		case SHT_RELA:
			fprintf(stderr,
					"RELA relocations not supported on this architecture\n");
			return NULL;
#else
		case SHT_REL:
			fprintf(stderr,
					"REL relocations not supported on this architecture\n");
			return NULL;
#endif

		default:
			if (sec->header.sh_type >= SHT_LOPROC) {
				/* Assume processor specific section types are debug
				   info and can safely be ignored.  If this is ever not
				   the case (Hello MIPS?), don't put ifdefs here but
				   create an arch_load_proc_section().  */
				break;
			}

			fprintf(stderr, "can't handle sections of type %ld\n",
					(long) sec->header.sh_type);
			return NULL;
		}
	}

	/* Do what sort of interpretation as needed by each section.  */

	shstrtab = f->sections[f->header.e_shstrndx]->contents;

	for (i = 0; i < shnum; ++i) {
		struct obj_section *sec = f->sections[i];
		sec->name = shstrtab + sec->header.sh_name;
	}

	for (i = 0; i < shnum; ++i) {
		struct obj_section *sec = f->sections[i];

		if (sec->header.sh_flags & SHF_ALLOC)
			obj_insert_section_load_order(f, sec);

		switch (sec->header.sh_type) {
		case SHT_SYMTAB:
			{
				unsigned long nsym, j;
				char *strtab;
				ElfW(Sym) * sym;

				if (sec->header.sh_entsize != sizeof(ElfW(Sym))) {
					fprintf(stderr, "symbol size mismatch: %lu != %lu\n",
							(unsigned long) sec->header.sh_entsize,
							(unsigned long) sizeof(ElfW(Sym)));
					return NULL;
				}

				nsym = sec->header.sh_size / sizeof(ElfW(Sym));
				strtab = f->sections[sec->header.sh_link]->contents;
				sym = (ElfW(Sym) *) sec->contents;

				/* Allocate space for a table of local symbols.  */
				j = f->local_symtab_size = sec->header.sh_info;
				f->local_symtab = xmalloc(j *=
										  sizeof(struct obj_symbol *));
				memset(f->local_symtab, 0, j);

				/* Insert all symbols into the hash table.  */
				for (j = 1, ++sym; j < nsym; ++j, ++sym) {
					const char *name;
					if (sym->st_name)
						name = strtab + sym->st_name;
		else
						name = f->sections[sym->st_shndx]->name;

					obj_add_symbol(f, name, j, sym->st_info, sym->st_shndx,
								   sym->st_value, sym->st_size);
		}
	}
			break;

		case SHT_RELM:
			if (sec->header.sh_entsize != sizeof(ElfW(RelM))) {
				fprintf(stderr,
						"relocation entry size mismatch: %lu != %lu\n",
						(unsigned long) sec->header.sh_entsize,
						(unsigned long) sizeof(ElfW(RelM)));
				return NULL;
			}
			break;
		}
	}

	return f;
}

static void hide_special_symbols(struct obj_file *f)
{
	static const char *const specials[] = {
		"cleanup_module",
		"init_module",
		"kernel_version",
		NULL
	};

	struct obj_symbol *sym;
	const char *const *p;

	for (p = specials; *p; ++p)
		if ((sym = obj_find_symbol(f, *p)) != NULL)
			sym->info =
				ELFW(ST_INFO) (STB_LOCAL, ELFW(ST_TYPE) (sym->info));
}



extern int insmod_main( int argc, char **argv)
{
	int k_crcs;
	int k_new_syscalls;
	int len;
	char *tmp;
	unsigned long m_size;
	ElfW(Addr) m_addr;
	FILE *fp;
	struct obj_file *f;
	char m_name[BUFSIZ + 1] = "\0";
	int exit_status = FALSE;
	int m_has_modinfo;
#ifdef BB_FEATURE_INSMOD_VERSION_CHECKING
	int k_version;
	char k_strversion[STRVERSIONLEN];
	char m_strversion[STRVERSIONLEN];
	int m_version;
	int m_crcs;
#endif


	if (argc <= 1) {
		usage(insmod_usage);
	}

	/* Parse any options */
	while (--argc > 0 && **(++argv) == '-') {
		while (*(++(*argv))) {
			switch (**argv) {
			case 'f':			/* force loading */
				flag_force_load = 1;
				break;
			case 'k':			/* module loaded by kerneld, auto-cleanable */
				flag_autoclean = 1;
				break;
			case 'v':			/* verbose output */
				flag_verbose = 1;
				break;
			case 'x':			/* do not export externs */
				flag_export = 0;
				break;
			default:
				usage(insmod_usage);
			}
		}
	}

	if (argc <= 0) {
		usage(insmod_usage);
	}
	/* Grab the module name */
	if ((tmp = strrchr(*argv, '/')) != NULL) {
		tmp++;
	} else {
		tmp = *argv;
	}
	len = strlen(tmp);

	if (len > 2 && tmp[len - 2] == '.' && tmp[len - 1] == 'o')
		len -= 2;
	memcpy(m_name, tmp, len);
	strcpy(m_fullName, m_name);
	strcat(m_fullName, ".o");

	/* Get a filedesc for the module */
	if ((fp = fopen(*argv, "r")) == NULL) {
		/* Hmpf.  Could not open it. Search through _PATH_MODULES to find a module named m_name */
		if (recursiveAction(_PATH_MODULES, TRUE, FALSE, FALSE,
							findNamedModule, 0, m_fullName) == TRUE) 
		{
			if (m_filename[0] == '\0'
				|| ((fp = fopen(m_filename, "r")) == NULL)) 
			{
				perror("No module by that name found in " _PATH_MODULES
					   "\n");
				exit(FALSE);
			}
		}
	} else
		memcpy(m_filename, *argv, strlen(*argv));


	if ((f = obj_load(fp)) == NULL) {
		perror("Could not load the module\n");
		exit(FALSE);
	}

	if (get_modinfo_value(f, "kernel_version") == NULL)
		m_has_modinfo = 0;
	else
		m_has_modinfo = 1;

#ifdef BB_FEATURE_INSMOD_VERSION_CHECKING
	/* Version correspondence?  */

	k_version = get_kernel_version(k_strversion);
	if (m_has_modinfo) {
		m_version = new_get_module_version(f, m_strversion);
	} else {
		m_version = old_get_module_version(f, m_strversion);
		if (m_version == -1) {
			fprintf(stderr,
					"couldn't find the kernel version the module was compiled for\n");
			goto out;
		}
	}

	if (strncmp(k_strversion, m_strversion, STRVERSIONLEN) != 0) {
		if (flag_force_load) {
			fprintf(stderr, "Warning: kernel-module version mismatch\n"
					"\t%s was compiled for kernel version %s\n"
					"\twhile this kernel is version %s\n",
					m_filename, m_strversion, k_strversion);
		} else {
			fprintf(stderr, "kernel-module version mismatch\n"
					"\t%s was compiled for kernel version %s\n"
					"\twhile this kernel is version %s.\n",
					m_filename, m_strversion, k_strversion);
			goto out;
		}
	}
	k_crcs = 0;
#endif							/* BB_FEATURE_INSMOD_VERSION_CHECKING */

	k_new_syscalls = !query_module(NULL, 0, NULL, 0, NULL);

	if (k_new_syscalls) {
#ifdef BB_FEATURE_INSMOD_NEW_KERNEL
		if (!new_get_kernel_symbols())
			goto out;
		k_crcs = new_is_kernel_checksummed();
#else
		fprintf(stderr, "Not configured to support new kernels\n");
		goto out;
#endif
	} else {
#ifdef BB_FEATURE_INSMOD_OLD_KERNEL
		if (!old_get_kernel_symbols())
			goto out;
		k_crcs = old_is_kernel_checksummed();
#else
		fprintf(stderr, "Not configured to support old kernels\n");
		goto out;
#endif
	}

#ifdef BB_FEATURE_INSMOD_VERSION_CHECKING
	if (m_has_modinfo)
		m_crcs = new_is_module_checksummed(f);
	else
		m_crcs = old_is_module_checksummed(f);

	if (m_crcs != k_crcs)
		obj_set_symbol_compare(f, ncv_strcmp, ncv_symbol_hash);
#endif							/* BB_FEATURE_INSMOD_VERSION_CHECKING */

	/* Let the module know about the kernel symbols.  */
	add_kernel_symbols(f);

	/* Allocate common symbols, symbol tables, and string tables.  */

	if (k_new_syscalls 
		? !new_create_this_module(f, m_name)
		: !old_create_mod_use_count(f)) 
	{
		goto out;
	}

	if (!obj_check_undefineds(f)) {
		goto out;
	}
	obj_allocate_commons(f);

	if (optind < argc) {
		if (m_has_modinfo
			? !new_process_module_arguments(f, argc - optind, argv + optind) 
			: !old_process_module_arguments(f, argc - optind, argv + optind)) 
		{
			goto out;
		}
	}

	arch_create_got(f);
	hide_special_symbols(f);

	if (k_new_syscalls)
		new_create_module_ksymtab(f);

	/* Find current size of the module */
	m_size = obj_load_size(f);


	errno = 0;
	m_addr = create_module(m_name, m_size);
	switch (errno) {
	case 0:
		break;
	case EEXIST:
		fprintf(stderr, "A module named %s already exists\n", m_name);
		goto out;
	case ENOMEM:
		fprintf(stderr,
				"Can't allocate kernel memory for module; needed %lu bytes\n",
				m_size);
		goto out;
	default:
		perror("create_module: %m");
		goto out;
	}

	if (!obj_relocate(f, m_addr)) {
		delete_module(m_name);
		goto out;
	}

	if (k_new_syscalls 
		? !new_init_module(m_name, f, m_size)
		: !old_init_module(m_name, f, m_size)) 
	{
		delete_module(m_name);
		goto out;
	}

	exit_status = TRUE;

out:
	fclose(fp);
	return(exit_status);
}