1 /*
2  * util.c --- utilities for the debugfs program
3  *
4  * Copyright (C) 1993, 1994 Theodore Ts'o.  This file may be
5  * redistributed under the terms of the GNU Public License.
6  *
7  */
8 
9 #define _XOPEN_SOURCE 600 /* needed for strptime */
10 
11 #include <stdio.h>
12 #include <unistd.h>
13 #include <stdlib.h>
14 #include <ctype.h>
15 #include <string.h>
16 #include <time.h>
17 #include <signal.h>
18 #ifdef HAVE_GETOPT_H
19 #include <getopt.h>
20 #else
21 extern int optind;
22 extern char *optarg;
23 #endif
24 #ifdef HAVE_OPTRESET
25 extern int optreset;		/* defined by BSD, but not others */
26 #endif
27 
28 #include "ss/ss.h"
29 #include "debugfs.h"
30 
31 /*
32  * This function resets the libc getopt() function, which keeps
33  * internal state.  Bad design!  Stupid libc API designers!  No
34  * biscuit!
35  *
36  * BSD-derived getopt() functions require that optind be reset to 1 in
37  * order to reset getopt() state.  This used to be generally accepted
38  * way of resetting getopt().  However, glibc's getopt()
39  * has additional getopt() state beyond optind, and requires that
40  * optind be set zero to reset its state.  So the unfortunate state of
41  * affairs is that BSD-derived versions of getopt() misbehave if
42  * optind is set to 0 in order to reset getopt(), and glibc's getopt()
43  * will core dump if optind is set 1 in order to reset getopt().
44  *
45  * More modern versions of BSD require that optreset be set to 1 in
46  * order to reset getopt().   Sigh.  Standards, anyone?
47  *
48  * We hide the hair here.
49  */
reset_getopt(void)50 void reset_getopt(void)
51 {
52 #if defined(__GLIBC__) || defined(__linux__)
53 	optind = 0;
54 #else
55 	optind = 1;
56 #endif
57 #ifdef HAVE_OPTRESET
58 	optreset = 1;		/* Makes BSD getopt happy */
59 #endif
60 }
61 
62 static const char *pager_search_list[] = { "pager", "more", "less", 0 };
63 static const char *pager_dir_list[] = { "/usr/bin", "/bin", 0 };
64 
find_pager(char * buf)65 static const char *find_pager(char *buf)
66 {
67 	const char **i, **j;
68 
69 	for (i = pager_search_list; *i; i++) {
70 		for (j = pager_dir_list; *j; j++) {
71 			sprintf(buf, "%s/%s", *j, *i);
72 			if (access(buf, X_OK) == 0)
73 				return(buf);
74 		}
75 	}
76 	return 0;
77 }
78 
open_pager(void)79 FILE *open_pager(void)
80 {
81 	FILE *outfile = 0;
82 	const char *pager = ss_safe_getenv("DEBUGFS_PAGER");
83 	char buf[80];
84 
85 	signal(SIGPIPE, SIG_IGN);
86 	if (!isatty(1))
87 		return stdout;
88 	if (!pager)
89 		pager = ss_safe_getenv("PAGER");
90 	if (!pager)
91 		pager = find_pager(buf);
92 	if (!pager ||
93 	    (strcmp(pager, "__none__") == 0) ||
94 	    ((outfile = popen(pager, "w")) == 0))
95 		return stdout;
96 	return outfile;
97 }
98 
close_pager(FILE * stream)99 void close_pager(FILE *stream)
100 {
101 	if (stream && stream != stdout) pclose(stream);
102 }
103 
104 /*
105  * This routine is used whenever a command needs to turn a string into
106  * an inode.
107  */
string_to_inode(char * str)108 ext2_ino_t string_to_inode(char *str)
109 {
110 	ext2_ino_t	ino;
111 	int		len = strlen(str);
112 	char		*end;
113 	int		retval;
114 
115 	/*
116 	 * If the string is of the form <ino>, then treat it as an
117 	 * inode number.
118 	 */
119 	if ((len > 2) && (str[0] == '<') && (str[len-1] == '>')) {
120 		ino = strtoul(str+1, &end, 0);
121 		if (*end=='>')
122 			return ino;
123 	}
124 
125 	retval = ext2fs_namei(current_fs, root, cwd, str, &ino);
126 	if (retval) {
127 		com_err(str, retval, 0);
128 		return 0;
129 	}
130 	return ino;
131 }
132 
133 /*
134  * This routine returns 1 if the filesystem is not open, and prints an
135  * error message to that effect.
136  */
check_fs_open(char * name)137 int check_fs_open(char *name)
138 {
139 	if (!current_fs) {
140 		com_err(name, 0, "Filesystem not open");
141 		return 1;
142 	}
143 	return 0;
144 }
145 
146 /*
147  * This routine returns 1 if a filesystem is open, and prints an
148  * error message to that effect.
149  */
check_fs_not_open(char * name)150 int check_fs_not_open(char *name)
151 {
152 	if (current_fs) {
153 		com_err(name, 0,
154 			"Filesystem %s is still open.  Close it first.\n",
155 			current_fs->device_name);
156 		return 1;
157 	}
158 	return 0;
159 }
160 
161 /*
162  * This routine returns 1 if a filesystem is not opened read/write,
163  * and prints an error message to that effect.
164  */
check_fs_read_write(char * name)165 int check_fs_read_write(char *name)
166 {
167 	if (!(current_fs->flags & EXT2_FLAG_RW)) {
168 		com_err(name, 0, "Filesystem opened read/only");
169 		return 1;
170 	}
171 	return 0;
172 }
173 
174 /*
175  * This routine returns 1 if a filesystem is doesn't have its inode
176  * and block bitmaps loaded, and prints an error message to that
177  * effect.
178  */
check_fs_bitmaps(char * name)179 int check_fs_bitmaps(char *name)
180 {
181 	if (!current_fs->block_map || !current_fs->inode_map) {
182 		com_err(name, 0, "Filesystem bitmaps not loaded");
183 		return 1;
184 	}
185 	return 0;
186 }
187 
188 /*
189  * This function takes a __u32 time value and converts it to a string,
190  * using ctime
191  */
time_to_string(__u32 cl)192 char *time_to_string(__u32 cl)
193 {
194 	static int	do_gmt = -1;
195 	time_t		t = (time_t) cl;
196 	const char	*tz;
197 
198 	if (do_gmt == -1) {
199 		/* The diet libc doesn't respect the TZ environemnt variable */
200 		tz = ss_safe_getenv("TZ");
201 		if (!tz)
202 			tz = "";
203 		do_gmt = !strcmp(tz, "GMT");
204 	}
205 
206 	return asctime((do_gmt) ? gmtime(&t) : localtime(&t));
207 }
208 
209 /*
210  * Parse a string as a time.  Return ((time_t)-1) if the string
211  * doesn't appear to be a sane time.
212  */
string_to_time(const char * arg)213 time_t string_to_time(const char *arg)
214 {
215 	struct	tm	ts;
216 	time_t		ret;
217 	char *tmp;
218 
219 	if (strcmp(arg, "now") == 0) {
220 		return time(0);
221 	}
222 	if (arg[0] == '@') {
223 		/* interpret it as an integer */
224 		ret = strtoul(arg+1, &tmp, 0);
225 		if (*tmp)
226 			return ((time_t) -1);
227 		return ret;
228 	}
229 	memset(&ts, 0, sizeof(ts));
230 #ifdef HAVE_STRPTIME
231 	strptime(arg, "%Y%m%d%H%M%S", &ts);
232 #else
233 	sscanf(arg, "%4d%2d%2d%2d%2d%2d", &ts.tm_year, &ts.tm_mon,
234 	       &ts.tm_mday, &ts.tm_hour, &ts.tm_min, &ts.tm_sec);
235 	ts.tm_year -= 1900;
236 	ts.tm_mon -= 1;
237 	if (ts.tm_year < 0 || ts.tm_mon < 0 || ts.tm_mon > 11 ||
238 	    ts.tm_mday < 0 || ts.tm_mday > 31 || ts.tm_hour > 23 ||
239 	    ts.tm_min > 59 || ts.tm_sec > 61)
240 		ts.tm_mday = 0;
241 #endif
242 	ts.tm_isdst = -1;
243 	ret = mktime(&ts);
244 	if (ts.tm_mday == 0 || ret == ((time_t) -1)) {
245 		/* Try it as an integer... */
246 		ret = strtoul(arg, &tmp, 0);
247 		if (*tmp)
248 			return ((time_t) -1);
249 	}
250 	return ret;
251 }
252 
253 /*
254  * This function will convert a string to an unsigned long, printing
255  * an error message if it fails, and returning success or failure in err.
256  */
parse_ulong(const char * str,const char * cmd,const char * descr,int * err)257 unsigned long parse_ulong(const char *str, const char *cmd,
258 			  const char *descr, int *err)
259 {
260 	char		*tmp;
261 	unsigned long	ret;
262 
263 	ret = strtoul(str, &tmp, 0);
264 	if (*tmp == 0) {
265 		if (err)
266 			*err = 0;
267 		return ret;
268 	}
269 	com_err(cmd, 0, "Bad %s - %s", descr, str);
270 	if (err)
271 		*err = 1;
272 	else
273 		exit(1);
274 	return 0;
275 }
276 
277 /*
278  * This function will convert a string to an unsigned long long, printing
279  * an error message if it fails, and returning success or failure in err.
280  */
parse_ulonglong(const char * str,const char * cmd,const char * descr,int * err)281 unsigned long long parse_ulonglong(const char *str, const char *cmd,
282 				   const char *descr, int *err)
283 {
284 	char			*tmp;
285 	unsigned long long	ret;
286 
287 	ret = strtoull(str, &tmp, 0);
288 	if (*tmp == 0) {
289 		if (err)
290 			*err = 0;
291 		return ret;
292 	}
293 	com_err(cmd, 0, "Bad %s - %s", descr, str);
294 	if (err)
295 		*err = 1;
296 	else
297 		exit(1);
298 	return 0;
299 }
300 
301 /*
302  * This function will convert a string to a block number.  It returns
303  * 0 on success, 1 on failure.
304  */
strtoblk(const char * cmd,const char * str,blk64_t * ret)305 int strtoblk(const char *cmd, const char *str, blk64_t *ret)
306 {
307 	blk64_t	blk;
308 	int	err;
309 
310 	blk = parse_ulonglong(str, cmd, "block number", &err);
311 	*ret = blk;
312 	if (err)
313 		com_err(cmd, 0, "Invalid block number: %s", str);
314 	return err;
315 }
316 
317 /*
318  * This is a common helper function used by the command processing
319  * routines
320  */
common_args_process(int argc,char * argv[],int min_argc,int max_argc,const char * cmd,const char * usage,int flags)321 int common_args_process(int argc, char *argv[], int min_argc, int max_argc,
322 			const char *cmd, const char *usage, int flags)
323 {
324 	if (argc < min_argc || argc > max_argc) {
325 		com_err(argv[0], 0, "Usage: %s %s", cmd, usage);
326 		return 1;
327 	}
328 	if (flags & CHECK_FS_NOTOPEN) {
329 		if (check_fs_not_open(argv[0]))
330 			return 1;
331 	} else {
332 		if (check_fs_open(argv[0]))
333 			return 1;
334 	}
335 	if ((flags & CHECK_FS_RW) && check_fs_read_write(argv[0]))
336 		return 1;
337 	if ((flags & CHECK_FS_BITMAPS) && check_fs_bitmaps(argv[0]))
338 		return 1;
339 	return 0;
340 }
341 
342 /*
343  * This is a helper function used by do_stat, do_freei, do_seti, and
344  * do_testi, etc.  Basically, any command which takes a single
345  * argument which is a file/inode number specifier.
346  */
common_inode_args_process(int argc,char * argv[],ext2_ino_t * inode,int flags)347 int common_inode_args_process(int argc, char *argv[],
348 			      ext2_ino_t *inode, int flags)
349 {
350 	if (common_args_process(argc, argv, 2, 2, argv[0], "<file>", flags))
351 		return 1;
352 
353 	*inode = string_to_inode(argv[1]);
354 	if (!*inode)
355 		return 1;
356 	return 0;
357 }
358 
359 /*
360  * This is a helper function used by do_freeb, do_setb, and do_testb
361  */
common_block_args_process(int argc,char * argv[],blk64_t * block,blk64_t * count)362 int common_block_args_process(int argc, char *argv[],
363 			      blk64_t *block, blk64_t *count)
364 {
365 	int	err;
366 
367 	if (common_args_process(argc, argv, 2, 3, argv[0],
368 				"<block> [count]", CHECK_FS_BITMAPS))
369 		return 1;
370 
371 	if (strtoblk(argv[0], argv[1], block))
372 		return 1;
373 	if (*block == 0) {
374 		com_err(argv[0], 0, "Invalid block number 0");
375 		err = 1;
376 	}
377 
378 	if (argc > 2) {
379 		err = strtoblk(argv[0], argv[2], count);
380 		if (err)
381 			return 1;
382 	}
383 	return 0;
384 }
385 
debugfs_read_inode_full(ext2_ino_t ino,struct ext2_inode * inode,const char * cmd,int bufsize)386 int debugfs_read_inode_full(ext2_ino_t ino, struct ext2_inode * inode,
387 			const char *cmd, int bufsize)
388 {
389 	int retval;
390 
391 	retval = ext2fs_read_inode_full(current_fs, ino, inode, bufsize);
392 	if (retval) {
393 		com_err(cmd, retval, "while reading inode %u", ino);
394 		return 1;
395 	}
396 	return 0;
397 }
398 
debugfs_read_inode(ext2_ino_t ino,struct ext2_inode * inode,const char * cmd)399 int debugfs_read_inode(ext2_ino_t ino, struct ext2_inode * inode,
400 			const char *cmd)
401 {
402 	int retval;
403 
404 	retval = ext2fs_read_inode(current_fs, ino, inode);
405 	if (retval) {
406 		com_err(cmd, retval, "while reading inode %u", ino);
407 		return 1;
408 	}
409 	return 0;
410 }
411 
debugfs_write_inode_full(ext2_ino_t ino,struct ext2_inode * inode,const char * cmd,int bufsize)412 int debugfs_write_inode_full(ext2_ino_t ino,
413 			     struct ext2_inode *inode,
414 			     const char *cmd,
415 			     int bufsize)
416 {
417 	int retval;
418 
419 	retval = ext2fs_write_inode_full(current_fs, ino,
420 					 inode, bufsize);
421 	if (retval) {
422 		com_err(cmd, retval, "while writing inode %u", ino);
423 		return 1;
424 	}
425 	return 0;
426 }
427 
debugfs_write_inode(ext2_ino_t ino,struct ext2_inode * inode,const char * cmd)428 int debugfs_write_inode(ext2_ino_t ino, struct ext2_inode * inode,
429 			const char *cmd)
430 {
431 	int retval;
432 
433 	retval = ext2fs_write_inode(current_fs, ino, inode);
434 	if (retval) {
435 		com_err(cmd, retval, "while writing inode %u", ino);
436 		return 1;
437 	}
438 	return 0;
439 }
440 
debugfs_write_new_inode(ext2_ino_t ino,struct ext2_inode * inode,const char * cmd)441 int debugfs_write_new_inode(ext2_ino_t ino, struct ext2_inode * inode,
442 			    const char *cmd)
443 {
444 	int retval;
445 
446 	retval = ext2fs_write_new_inode(current_fs, ino, inode);
447 	if (retval) {
448 		com_err(cmd, retval, "while creating inode %u", ino);
449 		return 1;
450 	}
451 	return 0;
452 }
453 
454 /*
455  * Given a mode, return the ext2 file type
456  */
ext2_file_type(unsigned int mode)457 int ext2_file_type(unsigned int mode)
458 {
459 	if (LINUX_S_ISREG(mode))
460 		return EXT2_FT_REG_FILE;
461 
462 	if (LINUX_S_ISDIR(mode))
463 		return EXT2_FT_DIR;
464 
465 	if (LINUX_S_ISCHR(mode))
466 		return EXT2_FT_CHRDEV;
467 
468 	if (LINUX_S_ISBLK(mode))
469 		return EXT2_FT_BLKDEV;
470 
471 	if (LINUX_S_ISLNK(mode))
472 		return EXT2_FT_SYMLINK;
473 
474 	if (LINUX_S_ISFIFO(mode))
475 		return EXT2_FT_FIFO;
476 
477 	if (LINUX_S_ISSOCK(mode))
478 		return EXT2_FT_SOCK;
479 
480 	return 0;
481 }
482