NetBSD/sys/kern/exec_aout.c

257 lines
8.4 KiB
C

/* $NetBSD: exec_aout.c,v 1.25 2002/10/05 22:34:05 chs 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: exec_aout.c,v 1.25 2002/10/05 22:34:05 chs Exp $");
#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>
/*
* 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);
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;
int error;
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;
error = vn_marktext(epp->ep_vp);
if (error)
return (error);
/* set up command for text segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, round_page(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, round_page(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 */
if (execp->a_bss > 0)
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|VM_PROT_EXECUTE);
return exec_aout_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|VM_PROT_EXECUTE);
return exec_aout_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|VM_PROT_EXECUTE);
/*
* 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_aout_setup_stack(p, epp);
}
/*
* exec_aout_setup_stack(): Set up the stack segment for an a.out
* executable.
*
* Note that the ep_ssize parameter must be set to be the current stack
* limit; this is adjusted in the body of execve() to yield the
* appropriate stack segment usage once the argument length is
* calculated.
*
* This function returns an int for uniformity with other (future) formats'
* stack setup functions. They might have errors to return.
*/
int
exec_aout_setup_stack(struct proc *p, struct exec_package *epp)
{
epp->ep_maxsaddr = USRSTACK - MAXSSIZ;
epp->ep_minsaddr = USRSTACK;
epp->ep_ssize = p->p_rlimit[RLIMIT_STACK].rlim_cur;
/*
* set up commands for stack. note that this takes *two*, one to
* map the part of the stack which we can access, and one to map
* the part which we can't.
*
* arguably, it could be made into one, but that would require the
* addition of another mapping proc, which is unnecessary
*
* note that in memory, things assumed to be: 0 ... ep_maxsaddr
* <stack> ep_minsaddr
*/
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero,
((epp->ep_minsaddr - epp->ep_ssize) - epp->ep_maxsaddr),
epp->ep_maxsaddr, NULLVP, 0, VM_PROT_NONE);
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, epp->ep_ssize,
(epp->ep_minsaddr - epp->ep_ssize), NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
return 0;
}