/*      $NetBSD: exec_ecoff.c,v 1.34 2024/12/06 16:19:41 riastradh Exp $        */

/*
* Copyright (c) 1994 Adam Glass
* Copyright (c) 1993, 1994, 1996, 1999 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
*      for the NetBSD Project.
* 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_ecoff.c,v 1.34 2024/12/06 16:19:41 riastradh Exp $");

#include <sys/param.h>
#include <sys/types.h>

#include <sys/exec.h>
#include <sys/exec.h>
#include <sys/exec_ecoff.h>
#include <sys/module.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/sdt.h>
#include <sys/systm.h>
#include <sys/vnode.h>

MODULE(MODULE_CLASS_EXEC, exec_ecoff, NULL);

static struct execsw exec_ecoff_execsw = {
       .es_hdrsz = ECOFF_HDR_SIZE,
       .es_makecmds = exec_ecoff_makecmds,
       .u = {
               .ecoff_probe_func = cpu_exec_ecoff_probe,
       },
       .es_emul = &emul_netbsd,
       .es_prio = EXECSW_PRIO_ANY,
       .es_arglen = 0,
       .es_copyargs = copyargs,
       .es_setregs = cpu_exec_ecoff_setregs,
       .es_coredump = coredump_netbsd,
       .es_setup_stack = exec_setup_stack,
};

static int
exec_ecoff_modcmd(modcmd_t cmd, void *arg)
{
       switch (cmd) {
       case MODULE_CMD_INIT:
               return exec_add(&exec_ecoff_execsw, 1);

       case MODULE_CMD_FINI:
               return exec_remove(&exec_ecoff_execsw, 1);

       default:
               return SET_ERROR(ENOTTY);
       }
}

/*
* exec_ecoff_makecmds(): Check if it's an ecoff-format executable.
*
* Given a proc pointer and an exec package pointer, see if the referent
* of the epp is in ecoff format.  Check 'standard' magic numbers for
* this architecture.  If that fails, return failure.
*
* This function 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_ecoff_makecmds(struct lwp *l, struct exec_package *epp)
{
       int error;
       struct ecoff_exechdr *execp = epp->ep_hdr;

       if (epp->ep_hdrvalid < ECOFF_HDR_SIZE)
               return SET_ERROR(ENOEXEC);

       if (ECOFF_BADMAG(execp))
               return SET_ERROR(ENOEXEC);

       error = (*epp->ep_esch->u.ecoff_probe_func)(l, epp);

       /*
        * if there was an error or there are already vmcmds set up,
        * we return.  (the latter can happen if cpu_exec_ecoff_hook()
        * recursively invokes check_exec() to handle loading of a
        * dynamically linked binary's shared loader.
        */
       if (error || epp->ep_vmcmds.evs_cnt)
               return (error);

       /*
        * prepare the exec package to map the executable.
        */
       switch (execp->a.magic) {
       case ECOFF_OMAGIC:
               error = exec_ecoff_prep_omagic(l, epp, epp->ep_hdr,
                  epp->ep_vp);
               break;
       case ECOFF_NMAGIC:
               error = exec_ecoff_prep_nmagic(l, epp, epp->ep_hdr,
                  epp->ep_vp);
               break;
       case ECOFF_ZMAGIC:
               error = exec_ecoff_prep_zmagic(l, epp, epp->ep_hdr,
                  epp->ep_vp);
               break;
       default:
               return SET_ERROR(ENOEXEC);
       }

       /* set up the stack */
       if (!error)
               error = (*epp->ep_esch->es_setup_stack)(l, epp);

       if (error)
               kill_vmcmds(&epp->ep_vmcmds);

       return error;
}

/*
* exec_ecoff_prep_omagic(): Prepare a ECOFF OMAGIC binary's exec package
*/
int
exec_ecoff_prep_omagic(struct lwp *l, struct exec_package *epp,
   struct ecoff_exechdr *execp, struct vnode *vp)
{
       struct ecoff_aouthdr *eap = &execp->a;

       epp->ep_taddr = ECOFF_SEGMENT_ALIGN(execp, eap->text_start);
       epp->ep_tsize = eap->tsize;
       epp->ep_daddr = ECOFF_SEGMENT_ALIGN(execp, eap->data_start);
       epp->ep_dsize = eap->dsize + eap->bsize;
       epp->ep_entry = eap->entry;

       /* set up command for text and data segments */
       NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
           eap->tsize + eap->dsize, epp->ep_taddr, vp,
           ECOFF_TXTOFF(execp),
           VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);

       /* set up command for bss segment */
       if (eap->bsize > 0)
               NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, eap->bsize,
                   ECOFF_SEGMENT_ALIGN(execp, eap->bss_start), NULLVP, 0,
                   VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);

       return 0;
}

/*
* exec_ecoff_prep_nmagic(): Prepare a 'native' NMAGIC ECOFF binary's exec
*                           package.
*/
int
exec_ecoff_prep_nmagic(struct lwp *l, struct exec_package *epp,
   struct ecoff_exechdr *execp, struct vnode *vp)
{
       struct ecoff_aouthdr *eap = &execp->a;

       epp->ep_taddr = ECOFF_SEGMENT_ALIGN(execp, eap->text_start);
       epp->ep_tsize = eap->tsize;
       epp->ep_daddr = ECOFF_ROUND(eap->data_start, ECOFF_LDPGSZ);
       epp->ep_dsize = eap->dsize + eap->bsize;
       epp->ep_entry = eap->entry;

       /* set up command for text segment */
       NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, epp->ep_tsize,
           epp->ep_taddr, vp, ECOFF_TXTOFF(execp),
           VM_PROT_READ|VM_PROT_EXECUTE);

       /* set up command for data segment */
       NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, epp->ep_dsize,
           epp->ep_daddr, vp, ECOFF_DATOFF(execp),
           VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);

       /* set up command for bss segment */
       if (eap->bsize > 0)
               NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, eap->bsize,
                   ECOFF_SEGMENT_ALIGN(execp, eap->bss_start), NULLVP, 0,
                   VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);

       return 0;
}

/*
* exec_ecoff_prep_zmagic(): Prepare a ECOFF ZMAGIC binary's exec package
*
* First, set 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_ecoff_prep_zmagic(struct lwp *l, struct exec_package *epp,
   struct ecoff_exechdr *execp, struct vnode *vp)
{
       struct ecoff_aouthdr *eap = &execp->a;
       int error;

       epp->ep_taddr = ECOFF_SEGMENT_ALIGN(execp, eap->text_start);
       epp->ep_tsize = eap->tsize;
       epp->ep_daddr = ECOFF_SEGMENT_ALIGN(execp, eap->data_start);
       epp->ep_dsize = eap->dsize + eap->bsize;
       epp->ep_entry = eap->entry;

       error = vn_marktext(vp);
       if (error)
               return (error);

       /* set up command for text segment */
       NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, eap->tsize,
           epp->ep_taddr, vp, ECOFF_TXTOFF(execp),
           VM_PROT_READ|VM_PROT_EXECUTE);

       /* set up command for data segment */
       NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, eap->dsize,
           epp->ep_daddr, vp, ECOFF_DATOFF(execp),
           VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);

       /* set up command for bss segment */
       if (eap->bsize > 0)
               NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, eap->bsize,
                   ECOFF_SEGMENT_ALIGN(execp, eap->bss_start), NULLVP, 0,
                   VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);

       return 0;
}