bsect.c

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/* bsect.c  -  Boot sector handling */
/*
Copyright 1992-1998 Werner Almesberger.
Copyright 1999-2002 John Coffman.
All rights reserved.

Licensed under the terms contained in the file 'COPYING' in the 
source directory.

*/


#include <unistd.h>
#include <sys/types.h>
#include <sys/statfs.h>
#include <sys/stat.h>
#include <stdio.h>
#include <fcntl.h>
#include <errno.h>

#ifdef	_SYS_STATFS_H
#define	_I386_STATFS_H	/* two versions of statfs is not good ... */
#endif

#include <linux/fs.h>
#include <linux/hdreg.h>
#include <linux/fd.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <limits.h>
#include <assert.h>

#include "config.h"
#include "common.h"
#include "cfg.h"
#include "lilo.h"
#include "device.h"
#include "geometry.h"
#include "map.h"
#include "temp.h"
#include "partition.h"
#include "boot.h"
#include "bsect.h"
#include "bitmap.h"
#include "loader.h"
#include "edit.h"

#ifdef SHS_PASSWORDS
#include "shs2.h"
#endif
#if defined(LCF_UNIFY) || defined(LCF_BUILTIN)
#define EARLY_MAP
#endif


int boot_dev_nr;

static BOOT_SECTOR bsect,bsect_orig;
static DESCR_SECTORS descrs;
static char secondary_map[SECTOR_SIZE];
static unsigned char table[SECTOR_SIZE];	/* keytable & params */
static DEVICE dev;
static char *boot_devnam,*map_name;
static int fd;
static int image_base = 0,image = 0;
static char temp_map[PATH_MAX+1];
static char *fallback[MAX_IMAGES];
static int fallbacks = 0;
static unsigned short stage_flags;
static int image_menu_space = MAX_IMAGES;
static char *getval_user;

typedef struct Pass {
    long crc[MAX_PW_CRC];
    char *unique;
    char *label;
    struct Pass *next;
    } PASSWORD;

static PASSWORD *pwsave = NULL;

#ifdef LCF_BUILTIN
BUILTIN_FILE *select_loader(void)
{
    BUILTIN_FILE *loader = &Third;	/* MENU interface is the default */
    char *install = cfg_get_strg(cf_options,"install");
    char *bitmap  = cfg_get_strg(cf_options,"bitmap");
    
    if (!install) {
	if (bitmap) loader = &Bitmap;
    } 
    else if (strstr(install,"text")) loader = &Second;  /* text interface */
    else if (strstr(install,"menu")) loader = &Third;
    else if (bitmap) loader = &Bitmap;   /* menu interface (MDA, EGA, VGA) */
        
    return loader;
}
#endif


/* kludge:  'append="..."' may not contain keywords acted upon by 
   the LILO boot loader -- except "mem=XXX"
 */
#define MEM_OKAY 1
static void check_options(char *options)
{
static char *disallow[] = { 
#if !MEM_OKAY
			"mem=",
#endif
				"vga=", "kbd=", "lock", "nobd", NULL };
    char *here, **dis = disallow;
    int error = 0;

    if (verbose >= 5) printf("check_options: \"%s\"\n", options);
    while (*dis) {
	here = strstr(options, *dis);
	if (here) {
	    if (here[3] != '=' && (here[4]==' ' || here[4]==0) ) error=2;
#if !MEM_OKAY
	    if (*dis == disallow[0] && here[4]>='0' && here[4]<='9')
		error = 1 
		/*	  + (cfg_get_strg(cf_kernel,"initrd") != NULL ||
			     cfg_get_strg(cf_options,"initrd") != NULL) */
			     ;
#endif
	}
	if (error>1) die ("APPEND or LITERAL may not contain \"%s\"", *dis);
#if !MEM_OKAY
	if (error==1 && !nowarn) {
	    fprintf(errstd, "Warning: APPEND or LITERAL may not contain \"mem=\"\n");
	    error = 0;
	}
#endif
	++dis;
    }    
}

static int getval(char **cp, int low, int high, int default_value, int factor)
{
    int temp;
    
    if (!**cp) {
	if (factor && eflag) {
	    if (low==1) default_value--;
	    default_value *= factor;
	}
    }
    else if (ispunct(**cp)) {
	(*cp)++;
	if (factor && eflag) {
	    if (low==1) default_value--;
	    default_value *= factor;
	}
    } else {
	temp = strtol(*cp, cp, 0);
	if (!factor) default_value = temp;
	else {
	    if (**cp == 'p' || **cp == 'P') {
		(*cp)++;
		default_value = temp;
		temp /= factor;
		if (low==1) temp++;
	    } else {
		default_value = (low==1 ? temp-1 : temp)*factor;
	    }
	}
	
	if (temp < low || temp > high)
		die("%s: value out of range [%d,%d]", getval_user, low, high);
	if (**cp && !ispunct(**cp)) die("Invalid character: \"%c\"", **cp);
	if (**cp) (*cp)++;
    }
    if (verbose>=5) printf("getval: %d\n", default_value);
    
    return default_value;
}

void bmp_do_timer(char *cp, MENUTABLE *menu)
{
    if (!cp) {
        if (eflag) menu->t_row = menu->t_col = -1;  /* there is none, if not specified during edit */
    } else if (strcasecmp(cp,"none")==0) {
        menu->t_row = menu->t_col = -1;  /* there is none, if specified as "none" */
    } else {
	getval_user = "bmp-timer";
    	menu->t_col = getval(&cp, 1, 76, menu->t_col, 8);
    	menu->t_row = getval(&cp, 1, 30, menu->t_row, 16);

    	if (!*cp && !eflag) return;
    	menu->t_fg = getval(&cp, 0, 15, menu->fg, 0);
    	menu->t_bg = getval(&cp, 0, 15, eflag?15^menu->t_fg:menu->t_bg, 0);
    	menu->t_sh = getval(&cp, 0, 15, menu->t_fg, 0);
    }
}


void bmp_do_table(char *cp, MENUTABLE *menu)
{
    if (!cp) {
	if (eflag) cp = "";
	else return;		/* dont change anything */
    }
    
    getval_user = "bmp-table";
    menu->col = getval(&cp, 1, 80-MAX_IMAGE_NAME, menu->col/8 + 1, 8);
    menu->row = getval(&cp, 1, 29, menu->row/16 + 1, 16);
#if 0
    menu->ncol = getval(&cp, 1, 80/(MAX_IMAGE_NAME+2), 1, 0);
    menu->maxcol = getval(&cp, 3, MAX_IMAGES, (MAX_IMAGES+menu->ncol-1)/menu->ncol, 0);
    menu->xpitch = getval(&cp, MAX_IMAGE_NAME+2, 80/menu->ncol, MAX_IMAGE_NAME+6, 8);
#else
    menu->ncol = getval(&cp, 1, 80/(MAX_IMAGE_NAME+1), menu->ncol, 0);
    menu->maxcol = getval(&cp, 2, 30 - menu->row/16, eflag?30 - menu->row/16:menu->maxcol, 0);
    menu->xpitch = getval(&cp, MAX_IMAGE_NAME+1, menu->ncol==1?80-menu->col/8:(80-menu->col/8-MAX_IMAGE_NAME*menu->ncol)/(menu->ncol-1)+MAX_IMAGE_NAME, menu->xpitch/8, 8);
    menu->mincol = getval(&cp, 1, menu->maxcol, menu->mincol, 0);
#endif
    if ((menu->row + menu->maxcol*16 > 480 || 
         menu->col + (MAX_IMAGE_NAME+1)*8 + (menu->ncol-1)*menu->xpitch > 640)
          && !nowarn)  
       fprintf(errstd,"Warning: 'bmp-table' may spill off screen\n");
}


void bmp_do_colors(char *cp, MENUTABLE *menu)
{
    if (!cp) {
	if (eflag) cp = "";
	else return;		/* dont change anything */
    }

    getval_user = "bmp-colors";
    menu->fg = getval(&cp, 0, 15, menu->fg, 0);
    if (!*cp && !eflag) return;
    menu->bg = getval(&cp, 0, 15, menu->fg, 0);
    menu->sh = getval(&cp, 0, 15, menu->fg, 0);

    menu->h_fg = getval(&cp, 0, 15, menu->h_fg, 0);
    if (!*cp && !eflag) return;
    menu->h_bg = getval(&cp, 0, 15, menu->h_fg, 0);
    menu->h_sh = getval(&cp, 0, 15, menu->h_fg, 0);    	
}

void pw_file_update(int passw)
{
    PASSWORD *walk;
    int i;
    
    if (verbose>=4) printf("pw_file_update:  passw=%d\n", passw);

    if (passw && !test && pw_file) {
	if (fseek(pw_file,0L,SEEK_SET)) perror("pw_file_update");
    
	for (walk=pwsave; walk; walk=walk->next) {
	    fprintf(pw_file, "label=<\"%s\">", walk->label);
	    for (i=0; i<MAX_PW_CRC; i++) fprintf(pw_file, " 0x%08lX", walk->crc[i]);
	    fprintf(pw_file, "\n");
	}
    }
    if (pw_file) fclose(pw_file);
}

void pw_fill_cache(void)
{
    char line[MAX_TOKEN+1];
    char *brace;
    char *label;
    PASSWORD *new;
    int i;
     
    if (verbose>=5) printf("pw_fill_cache\n");    
    if (fseek(pw_file,0L,SEEK_SET)) perror("pw_fill_cache");
    
    while (fgets(line,MAX_TOKEN,pw_file)) {
    	if (verbose>=5) printf("   %s\n", line);
    	brace = strrchr(line,'>');
    	label = strchr(line,'<');
    	if (label && label[1]=='"' && brace && brace[-1]=='"') {
	    brace[-1] = 0;
	    if ( !(new = alloc_t(PASSWORD)) ) pdie("Out of memory");
	    new->next = pwsave;
	    pwsave = new;
	    new->unique = NULL;
	    new->label = stralloc(label+2);
	    if (verbose>=2) printf("Password file: label=%s\n", new->label);
	    brace++;
    	    for (i=0; i<MAX_PW_CRC; i++) {
		new->crc[i] = strtoul(brace,&label,0);
		brace = label;
    	    }
    	}
    	else die("Ill-formed line in .crc file");
    }
    if (verbose >=5) printf("end pw_fill_cache\n");
}

static void hash_password(char *password, long crcval[])
{
#ifdef CRC_PASSWORDS
   static long poly[] = {CRC_POLY1, CRC_POLY2, CRC_POLY3, CRC_POLY4, CRC_POLY5};
#endif
	long crc;
	int j;
	int i = strlen(password);
	
#ifdef SHS_PASSWORDS
	shsInit();
	shsUpdate(password, i);
	shsFinal();
#endif
	for (j=0; j<MAX_PW_CRC; j++) {
	    crcval[j] = crc =
#ifdef CRC_PASSWORDS
	    			crc32(password, i, poly[j]);
  #define PWTYPE "CRC-32"
#else
				shsInfo.digest[j];
  #define PWTYPE "SHS-160"
#endif
	    if(verbose >= 2) {
		if (j==0) printf("Password " PWTYPE " =");
		printf(" %08lX", crc);
	    }
	}
	if (verbose >= 2) printf("\n");
}


void pw_wipe(char *pass)
{
    int i;
    
    if (!pass) return;
    i = strlen(pass);
    while (i) pass[--i]=0;
    free(pass);
}


char *pw_input(void)
#if 1
{
    char *cp = getpass("");
    int i = strlen(cp);
    char *acp = stralloc(cp);

    while (i) cp[i--] = 0;
    return acp;    
}
#else
{
    char *pass;
    char buf[MAX_TOKEN+1];
    int i, ch;
    
    i = 0;
    fflush(stdout);
    while((ch=getchar())!='\n') if (i<MAX_TOKEN) buf[i++]=ch;
    buf[i]=0;
    pass = stralloc(buf);
    while (i) buf[--i]=0;
    return pass;
}
#endif

static void pw_get(char *pass, long crcval[], int option)
{
    PASSWORD *walk;
    char *pass2;
    char *label;
    
    label = cfg_get_strg(cf_all, "label");
    if (!label) label = cfg_get_strg(cf_top, "image");
    if (!label) label = cfg_get_strg(cf_top, "other");
    if (!label) die("Need label to get password");
    if ((pass2 = strrchr(pass,'/'))) label = pass2+1;

    for (walk=pwsave; walk; walk=walk->next) {
        if (pass == walk->unique ||
        	(!walk->unique && !strcmp(walk->label,label) && (walk->unique=pass)) ) {
            memcpy(crcval, walk->crc, MAX_PW_CRC*sizeof(long));
            return;
        }
    }
    walk = alloc_t(PASSWORD);
    if (!walk) die("Out of memory");
    walk->next = pwsave;
    pwsave = walk;
    walk->unique = pass;
    walk->label = stralloc(label);
    
    printf("\nEntry for  %s  used null password\n", label);
    pass = pass2 = NULL;
    do {
    	if (pass) {
    	    printf("   *** Phrases don't match ***\n");
    	    pw_wipe(pass);
    	    pw_wipe(pass2);
	}
	printf("Type passphrase: ");
	pass2 = pw_input();
	printf("Please re-enter: ");
	pass = pw_input();
    } while (strcmp(pass,pass2));
    printf("\n");
    pw_wipe(pass2);  
    hash_password(pass, walk->crc);
    pw_wipe(pass);
    memcpy(crcval, walk->crc, MAX_PW_CRC*sizeof(long));
}


static void retrieve_crc(long crcval[])
{
    int i;
    char *pass;
    
    if (!pwsave) {
	if (cfg_pw_open()) pw_fill_cache();
    }
    pass = cfg_get_strg(cf_all,"password");
    if (pass) pw_get(pass,crcval,0);
    else pw_get(cfg_get_strg(cf_options,"password"),crcval,1);

    if (verbose >= 1) {
        printf("Password found is");
        for (i=0; i<MAX_PW_CRC; i++) printf(" %08lX", crcval[i]);
        printf("\n");
    }
}



static void open_bsect(char *boot_dev)
{
    struct stat st;

    if (verbose > 0)
	printf("Reading boot sector from %s\n",boot_dev ? boot_dev :
	  "current root.");
    boot_devnam = boot_dev;
    if (boot_dev) {
	if ((fd = open(boot_dev,O_RDWR)) < 0)
	    die("open %s: %s",boot_dev,strerror(errno));
	if (fstat(fd,&st) < 0) die("stat %s: %s",boot_dev,strerror(errno));
	if (!S_ISBLK(st.st_mode)) boot_dev_nr = 0;
	else boot_dev_nr = st.st_rdev;
    }
    else {
	if (stat("/",&st) < 0) pdie("stat /");
#if 0
	if ((st.st_dev & PART_MASK) > PART_MAX)
#else
	if (MAJOR(st.st_dev) != MAJOR_MD &&
		(st.st_dev & P_MASK(st.st_dev)) > PART_MAX)
#endif
	    die("Can't put the boot sector on logical partition 0x%04X",
	      (int)st.st_dev);
	fd = dev_open(&dev,boot_dev_nr = st.st_dev,O_RDWR);
    }
    if (boot_dev_nr && !is_first(boot_dev_nr) && !nowarn)
	fprintf(errstd,"Warning: %s is not on the first disk\n",boot_dev ?
	  boot_dev : "current root");
    if (read(fd,(char *) &bsect,SECTOR_SIZE) != SECTOR_SIZE)
	die("read %s: %s",boot_dev ? boot_dev : dev.name,strerror(errno));
    bsect_orig = bsect;
    ireloc = part_nowrite(boot_dev);
}


void bsect_read(char *boot_dev,BOOT_SECTOR *buffer)
{
    open_bsect(boot_dev);
    *buffer = bsect;
    (void) close(fd);
}


static void menu_do_scheme(char *scheme, MENUTABLE *menu)
{
    static char khar[] = "kbgcrmywKBGCRMYW";
    unsigned int fg, bg;
    int i;
    unsigned char *at;
    /* order of color attributes is: