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/* $OpenBSD: exec_aout.c,v 1.10 2005/11/12 04:31:24 jsg Exp $ */
/* $NetBSD: exec_aout.c,v 1.14 1996/02/04 02:15:01 christos Exp $ */
/*
* Copyright (c) 1993, 1994 Christopher G. Demetriou
* 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. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Christopher G. Demetriou.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/exec.h>
#include <sys/resourcevar.h>
#include <uvm/uvm_extern.h>
#if defined(_KERN_DO_AOUT)
#if defined(COMPAT_AOUT)
void aout_compat_setup(struct exec_package *epp);
#endif
/*
* exec_aout_makecmds(): Check if it's an a.out-format executable.
*
* Given a proc pointer and an exec package pointer, see if the referent
* of the epp is in a.out format. First check 'standard' magic numbers for
* this architecture. If that fails, try a cpu-dependent hook.
*
* This function, in the former case, or the hook, in the latter, is
* responsible for creating a set of vmcmds which can be used to build
* the process's vm space and inserting them into the exec package.
*/
int
exec_aout_makecmds(struct proc *p, struct exec_package *epp)
{
u_long midmag, magic;
u_short mid;
int error;
struct exec *execp = epp->ep_hdr;
if (epp->ep_hdrvalid < sizeof(struct exec))
return ENOEXEC;
midmag = ntohl(execp->a_midmag);
mid = (midmag >> 16) & 0x3ff;
magic = midmag & 0xffff;
midmag = mid << 16 | magic;
switch (midmag) {
case (MID_MACHINE << 16) | ZMAGIC:
error = exec_aout_prep_zmagic(p, epp);
break;
case (MID_MACHINE << 16) | NMAGIC:
error = exec_aout_prep_nmagic(p, epp);
break;
case (MID_MACHINE << 16) | OMAGIC:
error = exec_aout_prep_omagic(p, epp);
break;
default:
error = cpu_exec_aout_makecmds(p, epp);
}
if (error)
kill_vmcmds(&epp->ep_vmcmds);
#ifdef COMPAT_AOUT
aout_compat_setup(epp);
#endif
return error;
}
/*
* exec_aout_prep_zmagic(): Prepare a 'native' ZMAGIC binary's exec package
*
* First, set of the various offsets/lengths in the exec package.
*
* Then, mark the text image busy (so it can be demand paged) or error
* out if this is not possible. Finally, set up vmcmds for the
* text, data, bss, and stack segments.
*/
int
exec_aout_prep_zmagic(struct proc *p, struct exec_package *epp)
{
struct exec *execp = epp->ep_hdr;
epp->ep_taddr = USRTEXT;
epp->ep_tsize = execp->a_text;
epp->ep_daddr = epp->ep_taddr + execp->a_text;
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/*
* check if vnode is in open for writing, because we want to
* demand-page out of it. if it is, don't do it, for various
* reasons
*/
if ((execp->a_text != 0 || execp->a_data != 0) &&
epp->ep_vp->v_writecount != 0) {
#ifdef DIAGNOSTIC
if (epp->ep_vp->v_flag & VTEXT)
panic("exec: a VTEXT vnode has writecount != 0");
#endif
return ETXTBSY;
}
vn_marktext(epp->ep_vp);
/* set up command for text segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
epp->ep_taddr, epp->ep_vp, 0, VM_PROT_READ|VM_PROT_EXECUTE);
/* set up command for data segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
epp->ep_daddr, epp->ep_vp, execp->a_text,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
epp->ep_daddr + execp->a_data, NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE);
return exec_setup_stack(p, epp);
}
/*
* exec_aout_prep_nmagic(): Prepare a 'native' NMAGIC binary's exec package
*/
int
exec_aout_prep_nmagic(struct proc *p, struct exec_package *epp)
{
struct exec *execp = epp->ep_hdr;
long bsize, baddr;
epp->ep_taddr = USRTEXT;
epp->ep_tsize = execp->a_text;
epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text, __LDPGSZ);
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/* set up command for text segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
epp->ep_taddr, epp->ep_vp, sizeof(struct exec),
VM_PROT_READ|VM_PROT_EXECUTE);
/* set up command for data segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec),
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
baddr = round_page(epp->ep_daddr + execp->a_data);
bsize = epp->ep_daddr + epp->ep_dsize - baddr;
if (bsize > 0)
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE);
return exec_setup_stack(p, epp);
}
/*
* exec_aout_prep_omagic(): Prepare a 'native' OMAGIC binary's exec package
*/
int
exec_aout_prep_omagic(struct proc *p, struct exec_package *epp)
{
struct exec *execp = epp->ep_hdr;
long dsize, bsize, baddr;
epp->ep_taddr = USRTEXT;
epp->ep_tsize = execp->a_text;
epp->ep_daddr = epp->ep_taddr + execp->a_text;
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/* set up command for text and data segments */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
baddr = round_page(epp->ep_daddr + execp->a_data);
bsize = epp->ep_daddr + epp->ep_dsize - baddr;
if (bsize > 0)
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE);
/*
* Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
* obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
* computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
* respectively to page boundaries.
* Compensate `ep_dsize' for the amount of data covered by the last
* text page.
*/
dsize = epp->ep_dsize + execp->a_text - round_page(execp->a_text);
epp->ep_dsize = (dsize > 0) ? dsize : 0;
return exec_setup_stack(p, epp);
}
#endif /* _KERN_DO_AOUT */
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