1 /*	$NetBSD: disklabel.c,v 1.5 2009/03/14 21:04:07 dsl 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 <sys/param.h>
35 #include <ufs/ufs/dinode.h>
36 #include <ufs/ffs/fs.h>
37 #include <sys/disklabel.h>
38 #include <machine/ahdilabel.h>
39 #include <unistd.h>
40 #include <string.h>
41 #include <stdlib.h>
42 #include <fcntl.h>
43 #include <err.h>
44 
45 #if (BBSIZE < MINBBSIZE)
46 #error BBSIZE is smaller than MINBBSIZE
47 #endif
48 
49 struct ahdilabel {
50 	u_int		 nsecs;
51 	daddr_t		 bslst;
52 	daddr_t		 bslend;
53 	u_int		 nroots;
54 	daddr_t		 *roots;
55 	u_int		 nparts;
56 	struct ahdi_part *parts;
57 };
58 
59 u_int	dkcksum(struct disklabel *);
60 u_int32_t readdisklabel(char *, struct disklabel *);
61 
62 static int  bsd_label(int, off_t, struct disklabel *);
63 static int  ahdi_label(int, u_int32_t *, struct disklabel *);
64 static int  ahdi_getparts(int, daddr_t, daddr_t, struct ahdilabel *);
65 
66 u_int
67 dkcksum (struct disklabel *dl)
68 {
69 	u_int16_t sum  = 0,
70 		  *st  = (u_int16_t *)dl,
71 		  *end = (u_int16_t *)&dl->d_partitions[dl->d_npartitions];
72 
73 	while (st < end)
74 		sum ^= *st++;
75 	return(sum);
76 }
77 
78 u_int32_t
79 readdisklabel (char *fn, struct disklabel *dl)
80 {
81 	int		 fd, e;
82 	u_int32_t	 bbsec;
83 
84 	memset(dl, 0, sizeof *dl);
85 
86 	if ((fd = open(fn, O_RDONLY)) < 0)
87 		err(EXIT_FAILURE, "%s", fn);
88 
89 	/* Try NetBSD/Atari format first */
90 	if ((e = bsd_label(fd, (off_t)0, dl)) < 0)
91 		err(EXIT_FAILURE, "%s", fn);
92 	if (!e)
93 		return(0);
94 
95 	/* Try unprotected AHDI format last */
96 	if ((e = ahdi_label(fd, &bbsec, dl)) < 0)
97 		err(EXIT_FAILURE, "%s", fn);
98 	if (!e)
99 		return(bbsec);
100 
101 	warnx("%s: Unknown disk label format.", fn);
102 	return(NO_BOOT_BLOCK);
103 }
104 
105 static int
106 bsd_label (int fd, off_t offs, struct disklabel *label)
107 {
108 	struct bootblock bb;
109 	struct disklabel *p;
110 
111 	if (lseek(fd, offs, SEEK_SET) != offs)
112 		return(-1);
113 	if (read(fd, &bb, sizeof(bb)) != sizeof(bb))
114 		return(-1);
115 
116 	p = (struct disklabel *)bb.bb_label;
117 	if (  (offs == 0 && bb.bb_magic != NBDAMAGIC)
118 	   || (offs != 0 && bb.bb_magic != AHDIMAGIC)
119 	   || p->d_npartitions > MAXPARTITIONS
120 	   || p->d_magic2 != DISKMAGIC
121 	   || p->d_magic  != DISKMAGIC
122 	   || dkcksum(p)  != 0
123 	   )	{
124 		return(1);
125 	}
126 
127 	*label = *p;
128 	return(0);
129 }
130 
131 static int
132 ahdi_label (int fd, u_int32_t *bbsec, struct disklabel *label)
133 {
134 	struct ahdilabel al;
135 	u_int		 i, j;
136 	int		 e;
137 
138 	memset(&al, 0, sizeof(al));
139 	if ((e = ahdi_getparts(fd, AHDI_BBLOCK, AHDI_BBLOCK, &al)))
140 		return(e);
141 
142 	/*
143 	 * Perform sanity checks.
144 	 */
145 	if (al.bslst == 0 || al.bslend == 0)
146 		return(1);
147 	if (al.nsecs == 0 || al.nparts == 0)
148 		return(1);
149 	if (al.nparts > AHDI_MAXPARTS)
150 		warnx("Too many AHDI partitions (%u).", al.nparts);
151 	for (i = 0; i < al.nparts; ++i) {
152 		struct ahdi_part *p1 = &al.parts[i];
153 		for (j = 0; j < al.nroots; ++j) {
154 			daddr_t	aux = al.roots[j];
155 			if (aux >= p1->ap_st && aux <= p1->ap_end)
156 				return(1);
157 		}
158 		for (j = i + 1; j < al.nparts; ++j) {
159 			struct ahdi_part *p2 = &al.parts[j];
160 			if (p1->ap_st >= p2->ap_st && p1->ap_st <= p2->ap_end)
161 				return(1);
162 			if (p2->ap_st >= p1->ap_st && p2->ap_st <= p1->ap_end)
163 				return(1);
164 		}
165 		if (p1->ap_st >= al.bslst && p1->ap_st <= al.bslend)
166 			return(1);
167 		if (al.bslst >= p1->ap_st && al.bslst <= p1->ap_end)
168 			return(1);
169 	}
170 
171 	/*
172 	 * Search for a NetBSD boot block
173 	 */
174 	for (i = 0; i < al.nparts; ++i) {
175 		struct ahdi_part *pd = &al.parts[i];
176 		u_int id = *((u_int32_t *)&pd->ap_flg);
177 
178 		if (id == AHDI_PID_NBD || id == AHDI_PID_RAW) {
179 			off_t	offs = pd->ap_st * AHDI_BSIZE;
180 			if ((e = bsd_label(fd, offs, label)) < 0)
181 				return(e);
182 			if (!e) {
183 				*bbsec = pd->ap_st;	/* got it */
184 				return(0);
185 			}
186 		}
187 	}
188 	*bbsec = NO_BOOT_BLOCK;	/* AHDI label, no NetBSD boot block */
189 	return(0);
190 }
191 
192 static int
193 ahdi_getparts(fd, rsec, esec, alab)
194 	int		 fd;
195 	daddr_t		 rsec,
196 			 esec;
197 	struct ahdilabel *alab;
198 {
199 	struct ahdi_part *part, *end;
200 	struct ahdi_root root;
201 	off_t		 ro;
202 
203 	ro = rsec * AHDI_BSIZE;
204 	if (lseek(fd, ro, SEEK_SET) != ro) {
205 		off_t	mend = lseek(fd, 0, SEEK_END);
206 		if (mend == -1 || mend > ro)
207 			return(-1);
208 		return(1);
209 	}
210 	if (read(fd, &root, sizeof(root)) != sizeof(root))
211 		return(-1);
212 
213 	if (rsec == AHDI_BBLOCK)
214 		end = &root.ar_parts[AHDI_MAXRPD];
215 	else end = &root.ar_parts[AHDI_MAXARPD];
216 	for (part = root.ar_parts; part < end; ++part) {
217 		u_int	id = *((u_int32_t *)&part->ap_flg);
218 		if (!(id & 0x01000000))
219 			continue;
220 		if ((id &= 0x00ffffff) == AHDI_PID_XGM) {
221 			int	e;
222 			daddr_t	aux = part->ap_st + esec;
223 			alab->roots = realloc(alab->roots,
224 					(alab->nroots + 1) * sizeof(*alab->roots));
225 			alab->roots[alab->nroots++] = aux;
226 			e = ahdi_getparts(fd, aux,
227 					   esec == AHDI_BBLOCK ? aux : esec, alab);
228 			if (e)
229 				return(e);
230 		} else {
231 			struct ahdi_part *p;
232 			alab->parts = realloc(alab->parts,
233 					(alab->nparts + 1) * sizeof(*alab->parts));
234 			p = &alab->parts[alab->nparts++];
235 			*((u_int32_t *)&p->ap_flg) = id;
236 			p->ap_st = part->ap_st + rsec;
237 			p->ap_end  = p->ap_st + part->ap_size - 1;
238 		}
239 	}
240 	alab->nsecs  = root.ar_hdsize;
241 	alab->bslst  = root.ar_bslst;
242 	alab->bslend = root.ar_bslst + root.ar_bslsize - 1;
243 	return(0);
244 }
245