1 /* $NetBSD: bsdlabel.c,v 1.4 2009/03/31 11:48:15 tsutsui Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Waldi Ravens. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Waldi Ravens. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <sys/types.h> 34 #include <stdlib.h> 35 #include <stdio.h> 36 #include <string.h> 37 #include "libtos.h" 38 #include "diskio.h" 39 #include "ahdilbl.h" 40 #include "disklbl.h" 41 42 static int dkcksum PROTO((struct disklabel *)); 43 44 int 45 bsd_getlabel(disk_t *dd, struct disklabel *dlp, u_int offset) 46 { 47 u_char *bblk; 48 u_int nsec; 49 int rv; 50 51 nsec = (BBMINSIZE + (dd->bsize - 1)) / dd->bsize; 52 bblk = disk_read(dd, offset, nsec); 53 if (bblk) { 54 u_int *end, *p; 55 56 end = (u_int *)&bblk[BBMINSIZE - sizeof(struct disklabel)]; 57 rv = 1; 58 for (p = (u_int *)bblk; p < end; ++p) { 59 struct disklabel *dl = (struct disklabel *)&p[1]; 60 if ( ( (p[0] == NBDAMAGIC && offset == 0) 61 || (p[0] == AHDIMAGIC && offset != 0) 62 || (u_char *)dl - bblk == 7168 63 ) 64 && dl->d_npartitions <= MAXPARTITIONS 65 && dl->d_magic2 == DISKMAGIC 66 && dl->d_magic == DISKMAGIC 67 && dkcksum(dl) == 0 68 ) { 69 memcpy(dlp, dl, sizeof(*dlp)); 70 rv = 0; 71 break; 72 } 73 } 74 free(bblk); 75 } 76 else rv = -1; 77 78 return(rv); 79 } 80 81 static int 82 dkcksum(struct disklabel *dl) 83 { 84 u_short *start, *end, sum = 0; 85 86 start = (u_short *)dl; 87 end = (u_short *)&dl->d_partitions[dl->d_npartitions]; 88 while (start < end) 89 sum ^= *start++; 90 return(sum); 91 } 92