/*      $OpenBSD: boot.c,v 1.57 2023/02/23 19:48:22 miod Exp $  */

/*
 * Copyright (c) 2003 Dale Rahn
 * Copyright (c) 1997,1998 Michael Shalayeff
 * 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.
 *
 * 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 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.
 *
 */

#include <sys/param.h>
#include <sys/reboot.h>
#include <sys/stat.h>
#include <libsa.h>
#include <lib/libsa/loadfile.h>
#include <lib/libkern/funcs.h>
#include <lib/libsa/arc4.h>

#include <stand/boot/bootarg.h>

#include "cmd.h"

#ifndef KERNEL
#define KERNEL "/bsd"
#endif

char prog_ident[40];
char *progname = "BOOT";

extern  const char version[];
struct cmd_state cmd;

/* bootprompt can be set by MD code to avoid prompt first time round */
int bootprompt = 1;
char *kernelfile = KERNEL;              /* can be changed by MD code */
int boottimeout = 5;                    /* can be changed by MD code */

char    rnddata[BOOTRANDOM_MAX] __aligned(sizeof(long));
struct rc4_ctx randomctx;

void
boot(dev_t bootdev)
{
        int fd, isupgrade = 0;
        int try = 0, st;
        uint64_t marks[MARK_MAX];

        machdep();

        snprintf(prog_ident, sizeof(prog_ident),
            ">> OpenBSD/" MACHINE " %s %s", progname, version);
        printf("%s\n", prog_ident);

        devboot(bootdev, cmd.bootdev);
        strlcpy(cmd.image, kernelfile, sizeof(cmd.image));
        cmd.boothowto = 0;
        cmd.conf = "/etc/boot.conf";
        cmd.timeout = boottimeout;

        if (upgrade()) {
                strlcpy(cmd.image, "/bsd.upgrade", sizeof(cmd.image));
                printf("upgrade detected: switching to %s\n", cmd.image);
                isupgrade = 1;
        }

        st = read_conf();

#ifdef HIBERNATE
        int bootdev_has_hibernate(void);

        if (bootdev_has_hibernate()) {
                strlcpy(cmd.image, "/bsd.booted", sizeof(cmd.image));
                printf("unhibernate detected: switching to %s\n", cmd.image);
                cmd.boothowto |= RB_UNHIBERNATE;
        }
#endif

        if (!bootprompt)
                snprintf(cmd.path, sizeof cmd.path, "%s:%s",
                    cmd.bootdev, cmd.image);

        while (1) {
                /* no boot.conf, or no boot cmd in there */
                if (bootprompt && st <= 0) {
                        do {
                                printf("boot> ");
                        } while(!getcmd());
                }

                if (loadrandom(BOOTRANDOM, rnddata, sizeof(rnddata)) == 0)
                        cmd.boothowto |= RB_GOODRANDOM;
#ifdef MDRANDOM
                if (mdrandom(rnddata, sizeof(rnddata)) == 0)
                        cmd.boothowto |= RB_GOODRANDOM;
#endif
#ifdef FWRANDOM
                if (fwrandom(rnddata, sizeof(rnddata)) == 0)
                        cmd.boothowto |= RB_GOODRANDOM;
#endif
                rc4_keysetup(&randomctx, rnddata, sizeof rnddata);
                rc4_skip(&randomctx, 1536);

                st = 0;
                bootprompt = 1; /* allow reselect should we fail */

                printf("booting %s: ", cmd.path);
                marks[MARK_START] = 0;
                if ((fd = loadfile(cmd.path, marks, LOAD_ALL)) != -1) {

                        /* Prevent re-upgrade: chmod a-x bsd.upgrade */
                        if (isupgrade) {
                                struct stat st;

                                if (fstat(fd, &st) == 0) {
                                        st.st_mode &= ~(S_IXUSR|S_IXGRP|S_IXOTH);
                                        if (fchmod(fd, st.st_mode) == -1)
                                                printf("fchmod a-x %s: failed\n",
                                                    cmd.path);
                                }
                        }
                        close(fd);
                        break;
                }

                kernelfile = KERNEL;
                try++;
                strlcpy(cmd.image, kernelfile, sizeof(cmd.image));
                printf(" failed(%d). will try %s\n", errno, kernelfile);

                if (try < 2) {
                        if (cmd.timeout > 0)
                                cmd.timeout++;
                } else {
                        if (cmd.timeout)
                                printf("Turning timeout off.\n");
                        cmd.timeout = 0;
                }
        }

        /* exec */
        run_loadfile(marks, cmd.boothowto);
}

int
loadrandom(char *name, char *buf, size_t buflen)
{
        char path[MAXPATHLEN];
        struct stat sb;
        int fd, i, error = 0;

        /* Extract the device name from the kernel we are loading. */
        for (i = 0; i < sizeof(cmd.path); i++) {
                if (cmd.path[i] == ':') {
                        strlcpy(path, cmd.path, i + 1);
                        snprintf(path + i, sizeof(path) - i, ":%s", name);
                        break;
                } else if (cmd.path[i] == '\0') {
                        snprintf(path, sizeof path, "%s:%s",
                            cmd.bootdev, name);
                        break;
                }
        }

        fd = open(path, O_RDONLY);
        if (fd == -1) {
                if (errno != EPERM)
                        printf("cannot open %s: %s\n", path, strerror(errno));
                return -1;
        }
        if (fstat(fd, &sb) == -1) {
                error = -1;
                goto done;
        }
        if (read(fd, buf, buflen) != buflen) {
                error = -1;
                goto done;
        }
        if (sb.st_mode & S_ISTXT) {
                printf("NOTE: random seed is being reused.\n");
                error = -1;
                goto done;
        }
        fchmod(fd, sb.st_mode | S_ISTXT);
done:
        close(fd);
        return (error);
}