/*      $OpenBSD: kvm_proc2.c,v 1.39 2024/07/08 13:18:26 claudio Exp $  */
/*      $NetBSD: kvm_proc.c,v 1.30 1999/03/24 05:50:50 mrg Exp $        */
/*-
 * Copyright (c) 1998 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Charles M. Hannum.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``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 FOUNDATION OR CONTRIBUTORS
 * 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.
 */
/*-
 * Copyright (c) 1994, 1995 Charles M. Hannum.  All rights reserved.
 * Copyright (c) 1989, 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software developed by the Computer Systems
 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
 * BG 91-66 and contributed to Berkeley.
 *
 * 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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 */

/*
 * Proc traversal interface for kvm.  ps and w are (probably) the exclusive
 * users of this code, so we've factored it out into a separate module.
 * Thus, we keep this grunge out of the other kvm applications (i.e.,
 * most other applications are interested only in open/close/read/nlist).
 */

#define __need_process
#include <sys/param.h>  /* NODEV */
#include <sys/types.h>
#include <sys/signal.h>
#include <sys/proc.h>
#include <sys/exec.h>
#include <sys/stat.h>
#include <sys/ucred.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/resource.h>
#include <sys/resourcevar.h>
#include <sys/signalvar.h>
#include <sys/pledge.h>
#include <sys/wait.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <nlist.h>
#include <kvm.h>

#include <uvm/uvm_extern.h>
#include <uvm/uvm_amap.h>
#include <machine/vmparam.h>
#include <machine/pmap.h>

#include <sys/sysctl.h>

#include <limits.h>
#include <errno.h>
#include <db.h>
#include <paths.h>

#include "kvm_private.h"

/*
 * Read proc's from memory file into buffer bp, which has space to hold
 * at most maxcnt procs.
 */
static int
kvm_proclist(kvm_t *kd, int op, int arg, struct process *pr,
    char *bp, int maxcnt, size_t esize)
{
        struct kinfo_proc kp;
        struct session sess;
        struct ucred ucred;
        struct proc proc, *p;
        struct process process, process2;
        struct pgrp pgrp;
        struct tty tty;
        struct timeval elapsed, monostart, monostop, realstart, realstop;
        struct nlist nl[3];
        struct sigacts sa, *sap;
        struct vmspace vm, *vmp;
        struct plimit limits, *limp;
        pid_t parent_pid, leader_pid;
        int cnt = 0;
        int dothreads = 0;
        int i;

        dothreads = op & KERN_PROC_SHOW_THREADS;
        op &= ~KERN_PROC_SHOW_THREADS;

        /* Anchor a time to compare process starting times from. */
        nl[0].n_name = "_time_second";
        nl[1].n_name = "_time_uptime";
        nl[2].n_name = NULL;
        if (kvm_nlist(kd, nl) != 0) {
                for (i = 0; nl[i].n_type != 0; ++i)
                        continue;
                _kvm_err(kd, kd->program, "%s: no such symbol", nl[i].n_name);
                return (-1);
        }
        timerclear(&realstop);
        timerclear(&monostop);
        if (KREAD(kd, nl[0].n_value, &realstop.tv_sec)) {
                _kvm_err(kd, kd->program, "cannot read time_second");
                return (-1);
        }
        if (KREAD(kd, nl[1].n_value, &monostop.tv_sec)) {
                _kvm_err(kd, kd->program, "cannot read time_uptime");
                return (-1);
        }

        /*
         * Modelled on sysctl_doproc() in sys/kern/kern_sysctl.c
         */
        for (; cnt < maxcnt && pr != NULL; pr = LIST_NEXT(&process, ps_list)) {
                if (KREAD(kd, (u_long)pr, &process)) {
                        _kvm_err(kd, kd->program, "can't read process at %lx",
                            (u_long)pr);
                        return (-1);
                }
                if (process.ps_pgrp == NULL)
                        continue;
                if (process.ps_flags & PS_EMBRYO)
                        continue;
                if (KREAD(kd, (u_long)process.ps_ucred, &ucred)) {
                        _kvm_err(kd, kd->program, "can't read ucred at %lx",
                            (u_long)process.ps_ucred);
                        return (-1);
                }
                if (KREAD(kd, (u_long)process.ps_pgrp, &pgrp)) {
                        _kvm_err(kd, kd->program, "can't read pgrp at %lx",
                            (u_long)process.ps_pgrp);
                        return (-1);
                }
                if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) {
                        _kvm_err(kd, kd->program, "can't read session at %lx",
                            (u_long)pgrp.pg_session);
                        return (-1);
                }
                if ((process.ps_flags & PS_CONTROLT) && sess.s_ttyp != NULL &&
                    KREAD(kd, (u_long)sess.s_ttyp, &tty)) {
                        _kvm_err(kd, kd->program, "can't read tty at %lx",
                            (u_long)sess.s_ttyp);
                        return (-1);
                }
                if (process.ps_pptr) {
                        if (KREAD(kd, (u_long)process.ps_pptr, &process2)) {
                                _kvm_err(kd, kd->program,
                                    "can't read process at %lx",
                                    (u_long)process.ps_pptr);
                                return (-1);
                        }
                        parent_pid = process2.ps_pid;
                }
                else
                        parent_pid = 0;
                if (sess.s_leader) {
                        if (KREAD(kd, (u_long)sess.s_leader, &process2)) {
                                _kvm_err(kd, kd->program,
                                    "can't read proc at %lx",
                                    (u_long)sess.s_leader);
                                return (-1);
                        }
                        leader_pid = process2.ps_pid;
                }
                else
                        leader_pid = 0;
                if (process.ps_sigacts) {
                        if (KREAD(kd, (u_long)process.ps_sigacts, &sa)) {
                                _kvm_err(kd, kd->program,
                                    "can't read sigacts at %lx",
                                    (u_long)process.ps_sigacts);
                                return (-1);
                        }
                        sap = &sa;
                }
                else
                        sap = NULL;

                switch (op) {
                case KERN_PROC_PID:
                        if (process.ps_pid != (pid_t)arg)
                                continue;
                        break;

                case KERN_PROC_PGRP:
                        if (pgrp.pg_id != (pid_t)arg)
                                continue;
                        break;

                case KERN_PROC_SESSION:
                        if (sess.s_leader == NULL ||
                            leader_pid != (pid_t)arg)
                                continue;
                        break;

                case KERN_PROC_TTY:
                        if ((process.ps_flags & PS_CONTROLT) == 0 ||
                            sess.s_ttyp == NULL ||
                            tty.t_dev != (dev_t)arg)
                                continue;
                        break;

                case KERN_PROC_UID:
                        if (ucred.cr_uid != (uid_t)arg)
                                continue;
                        break;

                case KERN_PROC_RUID:
                        if (ucred.cr_ruid != (uid_t)arg)
                                continue;
                        break;

                case KERN_PROC_ALL:
                        if (process.ps_flags & PS_SYSTEM)
                                continue;
                        break;

                case KERN_PROC_KTHREAD:
                        /* no filtering */
                        break;

                default:
                        _kvm_err(kd, kd->program, "invalid filter");
                        return (-1);
                }

                /*
                 * We're going to add another proc to the set.  If this
                 * will overflow the buffer, assume the reason is because
                 * nthreads (or the proc list) is corrupt and declare an error.
                 */
                if (cnt >= maxcnt) {
                        _kvm_err(kd, kd->program, "nthreads corrupt");
                        return (-1);
                }

                /* set up stuff that might not always be there */
                limp = &limits;
                if (!process.ps_limit ||
                    KREAD(kd, (u_long)process.ps_limit, &limits))
                        limp = NULL;

                vmp = NULL;

                if ((process.ps_flags & PS_ZOMBIE) == 0 &&
                    !KREAD(kd, (u_long)process.ps_vmspace, &vm))
                        vmp = &vm;

#define do_copy_str(_d, _s, _l) kvm_read(kd, (u_long)(_s), (_d), (_l)-1)
                FILL_KPROC(&kp, do_copy_str, &proc, &process,
                    &ucred, &pgrp, process.ps_mainproc, pr, &sess,
                    vmp, limp, sap, &process.ps_tu, 0, 1);

                /* stuff that's too painful to generalize */
                kp.p_ppid = parent_pid;
                kp.p_sid = leader_pid;
                if ((process.ps_flags & PS_CONTROLT) && sess.s_ttyp != NULL) {
                        kp.p_tdev = tty.t_dev;
                        if (tty.t_pgrp != NULL &&
                            tty.t_pgrp != process.ps_pgrp &&
                            KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) {
                                _kvm_err(kd, kd->program,
                                    "can't read tpgrp at %lx",
                                    (u_long)tty.t_pgrp);
                                return (-1);
                        }
                        kp.p_tpgid = tty.t_pgrp ? pgrp.pg_id : -1;
                        kp.p_tsess = PTRTOINT64(tty.t_session);
                } else {
                        kp.p_tpgid = -1;
                        kp.p_tdev = NODEV;
                }

                /* Convert the starting uptime to a starting UTC time. */
                if ((process.ps_flags & PS_ZOMBIE) == 0) {
                        monostart.tv_sec = kp.p_ustart_sec;
                        monostart.tv_usec = kp.p_ustart_usec;
                        timersub(&monostop, &monostart, &elapsed);
                        if (elapsed.tv_sec < 0)
                                timerclear(&elapsed);
                        timersub(&realstop, &elapsed, &realstart);
                        kp.p_ustart_sec = realstart.tv_sec;
                        kp.p_ustart_usec = realstart.tv_usec;
                }

                /* update %cpu for all threads */
                if (dothreads) {
                        if (KREAD(kd, (u_long)process.ps_mainproc, &proc)) {
                                _kvm_err(kd, kd->program,
                                    "can't read proc at %lx",
                                    (u_long)process.ps_mainproc);
                                return (-1);
                        }
                        kp.p_pctcpu = proc.p_pctcpu;
                        kp.p_stat   = proc.p_stat;
                } else {
                        kp.p_pctcpu = 0;
                        kp.p_stat = (process.ps_flags & PS_ZOMBIE) ? SDEAD :
                            SIDL;
                        for (p = TAILQ_FIRST(&process.ps_threads); p != NULL; 
                            p = TAILQ_NEXT(&proc, p_thr_link)) {
                                if (KREAD(kd, (u_long)p, &proc)) {
                                        _kvm_err(kd, kd->program,
                                            "can't read proc at %lx",
                                            (u_long)p);
                                        return (-1);
                                }
                                kp.p_pctcpu += proc.p_pctcpu;
                                /*
                                 * find best state:
                                 * ONPROC > RUN > STOP > SLEEP > ...
                                 */
                                if (proc.p_stat == SONPROC ||
                                    kp.p_stat == SONPROC)
                                        kp.p_stat = SONPROC;
                                else if (proc.p_stat == SRUN ||
                                    kp.p_stat == SRUN)
                                        kp.p_stat = SRUN;
                                else if (proc.p_stat == SSTOP ||
                                    kp.p_stat == SSTOP)
                                        kp.p_stat = SSTOP;
                                else if (proc.p_stat == SSLEEP)
                                        kp.p_stat = SSLEEP;
                        }
                }

                memcpy(bp, &kp, esize);
                bp += esize;
                ++cnt;

                /* Skip per-thread entries if not required by op */
                if (!dothreads)
                        continue;

                for (p = TAILQ_FIRST(&process.ps_threads); p != NULL; 
                    p = TAILQ_NEXT(&proc, p_thr_link)) {
                        if (KREAD(kd, (u_long)p, &proc)) {
                                _kvm_err(kd, kd->program,
                                    "can't read proc at %lx",
                                    (u_long)p);
                                return (-1);
                        }
                        FILL_KPROC(&kp, do_copy_str, &proc, &process,
                            &ucred, &pgrp, p, pr, &sess, vmp, limp, sap,
                            &proc.p_tu, 1, 1);

                        /* see above */
                        kp.p_ppid = parent_pid;
                        kp.p_sid = leader_pid;
                        if ((process.ps_flags & PS_CONTROLT) &&
                            sess.s_ttyp != NULL) {
                                kp.p_tdev = tty.t_dev;
                                if (tty.t_pgrp != NULL &&
                                    tty.t_pgrp != process.ps_pgrp &&
                                    KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) {
                                        _kvm_err(kd, kd->program,
                                            "can't read tpgrp at %lx",
                                            (u_long)tty.t_pgrp);
                                        return (-1);
                                }
                                kp.p_tpgid = tty.t_pgrp ? pgrp.pg_id : -1;
                                kp.p_tsess = PTRTOINT64(tty.t_session);
                        } else {
                                kp.p_tpgid = -1;
                                kp.p_tdev = NODEV;
                        }
                }

                memcpy(bp, &kp, esize);
                bp += esize;
                ++cnt;
#undef do_copy_str
        }
        return (cnt);
}

struct kinfo_proc *
kvm_getprocs(kvm_t *kd, int op, int arg, size_t esize, int *cnt)
{
        int mib[6], st, nthreads;
        void *procbase;
        size_t size;

        if ((ssize_t)esize < 0)
                return (NULL);

        if (ISALIVE(kd)) {
                size = 0;
                mib[0] = CTL_KERN;
                mib[1] = KERN_PROC;
                mib[2] = op;
                mib[3] = arg;
                mib[4] = esize;

                do {
                        mib[5] = 0;
                        st = sysctl(mib, 6, NULL, &size, NULL, 0);
                        if (st == -1) {
                                _kvm_syserr(kd, kd->program, "kvm_getprocs");
                                return (NULL);
                        }

                        size += size / 8; /* add ~10% */

                        procbase = _kvm_realloc(kd, kd->procbase, size);
                        if (procbase == NULL)
                                return (NULL);

                        kd->procbase = procbase;

                        mib[5] = size / esize;
                        st = sysctl(mib, 6, kd->procbase, &size, NULL, 0);
                        if (st == -1 && errno != ENOMEM) {
                                _kvm_syserr(kd, kd->program, "kvm_getprocs");
                                return (NULL);
                        }
                } while (st == -1);

                nthreads = size / esize;
        } else {
                struct nlist nl[5];
                int i, maxthread, maxprocess;
                struct process *pr;
                char *bp;

                if (esize > sizeof(struct kinfo_proc)) {
                        _kvm_syserr(kd, kd->program,
                            "kvm_getprocs: unknown fields requested: libkvm out of date?");
                        return (NULL);
                }

                memset(nl, 0, sizeof(nl));
                nl[0].n_name = "_nthreads";
                nl[1].n_name = "_nprocesses";
                nl[2].n_name = "_allprocess";
                nl[3].n_name = "_zombprocess";
                nl[4].n_name = NULL;

                if (kvm_nlist(kd, nl) != 0) {
                        for (i = 0; nl[i].n_type != 0; ++i)
                                ;
                        _kvm_err(kd, kd->program,
                            "%s: no such symbol", nl[i].n_name);
                        return (NULL);
                }
                if (KREAD(kd, nl[0].n_value, &maxthread)) {
                        _kvm_err(kd, kd->program, "can't read nthreads");
                        return (NULL);
                }
                if (KREAD(kd, nl[1].n_value, &maxprocess)) {
                        _kvm_err(kd, kd->program, "can't read nprocesses");
                        return (NULL);
                }
                maxthread += maxprocess;

                kd->procbase = _kvm_reallocarray(kd, NULL, maxthread, esize);
                if (kd->procbase == 0)
                        return (NULL);
                bp = (char *)kd->procbase;

                /* allprocess */
                if (KREAD(kd, nl[2].n_value, &pr)) {
                        _kvm_err(kd, kd->program, "cannot read allprocess");
                        return (NULL);
                }
                nthreads = kvm_proclist(kd, op, arg, pr, bp, maxthread, esize);
                if (nthreads < 0)
                        return (NULL);

                /* zombprocess */
                if (KREAD(kd, nl[3].n_value, &pr)) {
                        _kvm_err(kd, kd->program, "cannot read zombprocess");
                        return (NULL);
                }
                i = kvm_proclist(kd, op, arg, pr, bp + (esize * nthreads),
                    maxthread - nthreads, esize);
                if (i > 0)
                        nthreads += i;
        }
        if (kd->procbase != NULL)
                *cnt = nthreads;
        return (kd->procbase);
}