/*      $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;
}