1 /*
2  * Copyright (C) 1995, 1996, 1997 Wolfgang Solfrank
3  * Copyright (c) 1995 Martin Husemann
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by Martin Husemann
16  *	and Wolfgang Solfrank.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``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 AUTHORS 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 
34 #include <sys/cdefs.h>
35 #ifndef lint
36 __RCSID("$NetBSD: check.c,v 1.10 2000/04/25 23:02:51 jdolecek Exp $");
37 static const char rcsid[] =
38   "$FreeBSD: src/sbin/fsck_msdosfs/check.c,v 1.10 2004/02/05 15:47:46 bde Exp $";
39 #endif /* not lint */
40 
41 #include <stdlib.h>
42 #include <string.h>
43 #include <ctype.h>
44 #include <stdio.h>
45 #include <unistd.h>
46 #include <fcntl.h>
47 
48 #include "ext.h"
49 #include "fsutil.h"
50 
51 /*
52  * If the FAT > this size then skip comparing, lest we risk
53  * OOMing the framework. in the future we need to just re-write
54  * this whole thing and optimize for less memory
55  */
56 #define FAT_COMPARE_MAX_KB 4096
57 
58 int
checkfilesys(const char * fname)59 checkfilesys(const char *fname)
60 {
61 	int dosfs;
62 	struct bootblock boot;
63 	struct fatEntry *fat = NULL;
64 	int i, finish_dosdirsection=0;
65 	int mod = 0;
66 	int ret = 8;
67         int quiet = 0;
68         int skip_fat_compare = 0;
69 
70 	rdonly = alwaysno;
71 	if (!quiet)
72 		printf("** %s", fname);
73 
74 	dosfs = open(fname, rdonly ? O_RDONLY : O_RDWR, 0);
75 	if (dosfs < 0 && !rdonly) {
76 		dosfs = open(fname, O_RDONLY, 0);
77 		if (dosfs >= 0)
78 			pwarn(" (NO WRITE)\n");
79 		else if (!quiet)
80 			printf("\n");
81 		rdonly = 1;
82 	} else if (!quiet)
83 		printf("\n");
84 
85 	if (dosfs < 0) {
86 		perror("Can't open");
87 		return 8;
88 	}
89 
90 	if (readboot(dosfs, &boot) == FSFATAL) {
91 		close(dosfs);
92 		printf("\n");
93 		return 8;
94 	}
95 
96 	if (skipclean && preen && checkdirty(dosfs, &boot)) {
97 		printf("%s: ", fname);
98 		printf("FILESYSTEM CLEAN; SKIPPING CHECKS\n");
99 		ret = 0;
100 		goto out;
101 	}
102 
103         if (((boot.FATsecs * boot.BytesPerSec) / 1024) > FAT_COMPARE_MAX_KB)
104             skip_fat_compare = 1;
105 
106 	if (!quiet)  {
107                 if (skip_fat_compare)
108                         printf("** Phase 1 - Read FAT (compare skipped)\n");
109 		else if (boot.ValidFat < 0)
110 			printf("** Phase 1 - Read and Compare FATs\n");
111 		else
112 			printf("** Phase 1 - Read FAT\n");
113 	}
114 
115 	mod |= readfat(dosfs, &boot, boot.ValidFat >= 0 ? boot.ValidFat : 0, &fat);
116 	if (mod & FSFATAL) {
117 		printf("Fatal error during readfat()\n");
118 		close(dosfs);
119 		return 8;
120 	}
121 
122 	if (!skip_fat_compare && boot.ValidFat < 0)
123 		for (i = 1; i < (int)boot.FATs; i++) {
124 			struct fatEntry *currentFat;
125 
126 			mod |= readfat(dosfs, &boot, i, &currentFat);
127 
128 			if (mod & FSFATAL) {
129 				printf("Fatal error during readfat() for comparison\n");
130 				goto out;
131 			}
132 
133 			mod |= comparefat(&boot, fat, currentFat, i);
134 			free(currentFat);
135 			if (mod & FSFATAL) {
136 				printf("Fatal error during FAT comparison\n");
137 				goto out;
138 			}
139 		}
140 
141 	if (!quiet)
142 		printf("** Phase 2 - Check Cluster Chains\n");
143 
144 	mod |= checkfat(&boot, fat);
145 	if (mod & FSFATAL) {
146 		printf("Fatal error during FAT check\n");
147 		goto out;
148 	}
149 	/* delay writing FATs */
150 
151 	if (!quiet)
152 		printf("** Phase 3 - Checking Directories\n");
153 
154 	mod |= resetDosDirSection(&boot, fat);
155 	finish_dosdirsection = 1;
156 	if (mod & FSFATAL) {
157 		printf("Fatal error during resetDosDirSection()\n");
158 		goto out;
159 	}
160 	/* delay writing FATs */
161 
162 	mod |= handleDirTree(dosfs, &boot, fat);
163 	if (mod & FSFATAL)
164 		goto out;
165 
166 	if (!quiet)
167 		printf("** Phase 4 - Checking for Lost Files\n");
168 
169 	mod |= checklost(dosfs, &boot, fat);
170 	if (mod & FSFATAL)
171 		goto out;
172 
173 	/* now write the FATs */
174 	if (mod & FSFATMOD) {
175 		if (ask(1, "Update FATs")) {
176 			mod |= writefat(dosfs, &boot, fat, mod & FSFIXFAT);
177 			if (mod & FSFATAL) {
178 				printf("Fatal error during writefat()\n");
179 				goto out;
180 			}
181 		} else
182 			mod |= FSERROR;
183 	}
184 
185 	if (boot.NumBad)
186 		pwarn("%d files, %d free (%d clusters), %d bad (%d clusters)\n",
187 		      boot.NumFiles,
188 		      boot.NumFree * boot.ClusterSize / 1024, boot.NumFree,
189 		      boot.NumBad * boot.ClusterSize / 1024, boot.NumBad);
190 	else
191 		pwarn("%d files, %d free (%d clusters)\n",
192 		      boot.NumFiles,
193 		      boot.NumFree * boot.ClusterSize / 1024, boot.NumFree);
194 
195 	if (mod && (mod & FSERROR) == 0) {
196 		if (mod & FSDIRTY) {
197 			if (ask(1, "MARK FILE SYSTEM CLEAN") == 0)
198 				mod &= ~FSDIRTY;
199 
200 			if (mod & FSDIRTY) {
201 				pwarn("MARKING FILE SYSTEM CLEAN\n");
202 				mod |= writefat(dosfs, &boot, fat, 1);
203 			} else {
204 				pwarn("\n***** FILE SYSTEM IS LEFT MARKED AS DIRTY *****\n");
205 				mod |= FSERROR; /* file system not clean */
206 			}
207 		}
208 	}
209 
210 	if (mod & (FSFATAL | FSERROR))
211 		goto out;
212 
213 	ret = 0;
214 
215     out:
216 	if (finish_dosdirsection)
217 		finishDosDirSection();
218 	free(fat);
219 	close(dosfs);
220 
221 	if (mod & (FSFATMOD|FSDIRMOD)) {
222 		pwarn("\n***** FILE SYSTEM WAS MODIFIED *****\n");
223 		return 4;
224 	}
225 
226 	return ret;
227 }
228