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path: root/miscutils/devfsd.c (plain)
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1/* vi: set sw=4 ts=4: */
2/*
3 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
4 */
5
6/*
7 devfsd implementation for busybox
8
9 Copyright (C) 2003 by Tito Ragusa <farmatito@tiscali.it>
10
11 Busybox version is based on some previous work and ideas
12 Copyright (C) [2003] by [Matteo Croce] <3297627799@wind.it>
13
14 devfsd.c
15
16 Main file for devfsd (devfs daemon for Linux).
17
18 Copyright (C) 1998-2002 Richard Gooch
19
20 devfsd.h
21
22 Header file for devfsd (devfs daemon for Linux).
23
24 Copyright (C) 1998-2000 Richard Gooch
25
26 compat_name.c
27
28 Compatibility name file for devfsd (build compatibility names).
29
30 Copyright (C) 1998-2002 Richard Gooch
31
32 expression.c
33
34 This code provides Borne Shell-like expression expansion.
35
36 Copyright (C) 1997-1999 Richard Gooch
37
38 This program is free software; you can redistribute it and/or modify
39 it under the terms of the GNU General Public License as published by
40 the Free Software Foundation; either version 2 of the License, or
41 (at your option) any later version.
42
43 This program is distributed in the hope that it will be useful,
44 but WITHOUT ANY WARRANTY; without even the implied warranty of
45 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
46 GNU General Public License for more details.
47
48 You should have received a copy of the GNU General Public License
49 along with this program; if not, write to the Free Software
50 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
51
52 Richard Gooch may be reached by email at rgooch@atnf.csiro.au
53 The postal address is:
54 Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia.
55*/
56
57//usage:#define devfsd_trivial_usage
58//usage: "mntpnt [-v]" IF_DEVFSD_FG_NP("[-fg][-np]")
59//usage:#define devfsd_full_usage "\n\n"
60//usage: "Manage devfs permissions and old device name symlinks\n"
61//usage: "\n mntpnt The mount point where devfs is mounted"
62//usage: "\n -v Print the protocol version numbers for devfsd"
63//usage: "\n and the kernel-side protocol version and exit"
64//usage: IF_DEVFSD_FG_NP(
65//usage: "\n -fg Run in foreground"
66//usage: "\n -np Exit after parsing the configuration file"
67//usage: "\n and processing synthetic REGISTER events,"
68//usage: "\n don't poll for events"
69//usage: )
70
71#include "libbb.h"
72#include "xregex.h"
73#include <syslog.h>
74
75#include <sys/un.h>
76#include <sys/sysmacros.h>
77
78/* Various defines taken from linux/major.h */
79#define IDE0_MAJOR 3
80#define IDE1_MAJOR 22
81#define IDE2_MAJOR 33
82#define IDE3_MAJOR 34
83#define IDE4_MAJOR 56
84#define IDE5_MAJOR 57
85#define IDE6_MAJOR 88
86#define IDE7_MAJOR 89
87#define IDE8_MAJOR 90
88#define IDE9_MAJOR 91
89
90
91/* Various defines taken from linux/devfs_fs.h */
92#define DEVFSD_PROTOCOL_REVISION_KERNEL 5
93#define DEVFSD_IOCTL_BASE 'd'
94/* These are the various ioctls */
95#define DEVFSDIOC_GET_PROTO_REV _IOR(DEVFSD_IOCTL_BASE, 0, int)
96#define DEVFSDIOC_SET_EVENT_MASK _IOW(DEVFSD_IOCTL_BASE, 2, int)
97#define DEVFSDIOC_RELEASE_EVENT_QUEUE _IOW(DEVFSD_IOCTL_BASE, 3, int)
98#define DEVFSDIOC_SET_CONFIG_DEBUG_MASK _IOW(DEVFSD_IOCTL_BASE, 4, int)
99#define DEVFSD_NOTIFY_REGISTERED 0
100#define DEVFSD_NOTIFY_UNREGISTERED 1
101#define DEVFSD_NOTIFY_ASYNC_OPEN 2
102#define DEVFSD_NOTIFY_CLOSE 3
103#define DEVFSD_NOTIFY_LOOKUP 4
104#define DEVFSD_NOTIFY_CHANGE 5
105#define DEVFSD_NOTIFY_CREATE 6
106#define DEVFSD_NOTIFY_DELETE 7
107#define DEVFS_PATHLEN 1024
108/* Never change this otherwise the binary interface will change */
109
110struct devfsd_notify_struct {
111 /* Use native C types to ensure same types in kernel and user space */
112 unsigned int type; /* DEVFSD_NOTIFY_* value */
113 unsigned int mode; /* Mode of the inode or device entry */
114 unsigned int major; /* Major number of device entry */
115 unsigned int minor; /* Minor number of device entry */
116 unsigned int uid; /* Uid of process, inode or device entry */
117 unsigned int gid; /* Gid of process, inode or device entry */
118 unsigned int overrun_count; /* Number of lost events */
119 unsigned int namelen; /* Number of characters not including '\0' */
120 /* The device name MUST come last */
121 char devname[DEVFS_PATHLEN]; /* This will be '\0' terminated */
122};
123
124#define BUFFER_SIZE 16384
125#define DEVFSD_VERSION "1.3.25"
126#define CONFIG_FILE "/etc/devfsd.conf"
127#define MODPROBE "/sbin/modprobe"
128#define MODPROBE_SWITCH_1 "-k"
129#define MODPROBE_SWITCH_2 "-C"
130#define CONFIG_MODULES_DEVFS "/etc/modules.devfs"
131#define MAX_ARGS (6 + 1)
132#define MAX_SUBEXPR 10
133#define STRING_LENGTH 255
134
135/* for get_uid_gid() */
136#define UID 0
137#define GID 1
138
139/* fork_and_execute() */
140# define DIE 1
141# define NO_DIE 0
142
143/* for dir_operation() */
144#define RESTORE 0
145#define SERVICE 1
146#define READ_CONFIG 2
147
148/* Update only after changing code to reflect new protocol */
149#define DEVFSD_PROTOCOL_REVISION_DAEMON 5
150
151/* Compile-time check */
152#if DEVFSD_PROTOCOL_REVISION_KERNEL != DEVFSD_PROTOCOL_REVISION_DAEMON
153#error protocol version mismatch. Update your kernel headers
154#endif
155
156#define AC_PERMISSIONS 0
157#define AC_MODLOAD 1
158#define AC_EXECUTE 2
159#define AC_MFUNCTION 3 /* not supported by busybox */
160#define AC_CFUNCTION 4 /* not supported by busybox */
161#define AC_COPY 5
162#define AC_IGNORE 6
163#define AC_MKOLDCOMPAT 7
164#define AC_MKNEWCOMPAT 8
165#define AC_RMOLDCOMPAT 9
166#define AC_RMNEWCOMPAT 10
167#define AC_RESTORE 11
168
169struct permissions_type {
170 mode_t mode;
171 uid_t uid;
172 gid_t gid;
173};
174
175struct execute_type {
176 char *argv[MAX_ARGS + 1]; /* argv[0] must always be the programme */
177};
178
179struct copy_type {
180 const char *source;
181 const char *destination;
182};
183
184struct action_type {
185 unsigned int what;
186 unsigned int when;
187};
188
189struct config_entry_struct {
190 struct action_type action;
191 regex_t preg;
192 union
193 {
194 struct permissions_type permissions;
195 struct execute_type execute;
196 struct copy_type copy;
197 }
198 u;
199 struct config_entry_struct *next;
200};
201
202struct get_variable_info {
203 const struct devfsd_notify_struct *info;
204 const char *devname;
205 char devpath[STRING_LENGTH];
206};
207
208static void dir_operation(int , const char * , int, unsigned long*);
209static void service(struct stat statbuf, char *path);
210static int st_expr_expand(char *, unsigned, const char *, const char *(*)(const char *, void *), void *);
211static const char *get_old_name(const char *, unsigned, char *, unsigned, unsigned);
212static int mksymlink(const char *oldpath, const char *newpath);
213static void read_config_file(char *path, int optional, unsigned long *event_mask);
214static void process_config_line(const char *, unsigned long *);
215static int do_servicing(int, unsigned long);
216static void service_name(const struct devfsd_notify_struct *);
217static void action_permissions(const struct devfsd_notify_struct *, const struct config_entry_struct *);
218static void action_execute(const struct devfsd_notify_struct *, const struct config_entry_struct *,
219 const regmatch_t *, unsigned);
220static void action_modload(const struct devfsd_notify_struct *info, const struct config_entry_struct *entry);
221static void action_copy(const struct devfsd_notify_struct *, const struct config_entry_struct *,
222 const regmatch_t *, unsigned);
223static void action_compat(const struct devfsd_notify_struct *, unsigned);
224static void free_config(void);
225static void restore(char *spath, struct stat source_stat, int rootlen);
226static int copy_inode(const char *, const struct stat *, mode_t, const char *, const struct stat *);
227static mode_t get_mode(const char *);
228static void signal_handler(int);
229static const char *get_variable(const char *, void *);
230static int make_dir_tree(const char *);
231static int expand_expression(char *, unsigned, const char *, const char *(*)(const char *, void *), void *,
232 const char *, const regmatch_t *, unsigned);
233static void expand_regexp(char *, size_t, const char *, const char *, const regmatch_t *, unsigned);
234static const char *expand_variable( char *, unsigned, unsigned *, const char *,
235 const char *(*)(const char *, void *), void *);
236static const char *get_variable_v2(const char *, const char *(*)(const char *, void *), void *);
237static char get_old_ide_name(unsigned, unsigned);
238static char *write_old_sd_name(char *, unsigned, unsigned, const char *);
239
240/* busybox functions */
241static int get_uid_gid(int flag, const char *string);
242static void safe_memcpy(char * dest, const char * src, int len);
243static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, const char *ptr);
244static unsigned int scan_dev_name(const char *d, unsigned int n, const char *ptr);
245
246/* Structs and vars */
247static struct config_entry_struct *first_config = NULL;
248static struct config_entry_struct *last_config = NULL;
249static char *mount_point = NULL;
250static volatile int caught_signal = FALSE;
251static volatile int caught_sighup = FALSE;
252static struct initial_symlink_struct {
253 const char *dest;
254 const char *name;
255} initial_symlinks[] = {
256 {"/proc/self/fd", "fd"},
257 {"fd/0", "stdin"},
258 {"fd/1", "stdout"},
259 {"fd/2", "stderr"},
260 {NULL, NULL},
261};
262
263static struct event_type {
264 unsigned int type; /* The DEVFSD_NOTIFY_* value */
265 const char *config_name; /* The name used in the config file */
266} event_types[] = {
267 {DEVFSD_NOTIFY_REGISTERED, "REGISTER"},
268 {DEVFSD_NOTIFY_UNREGISTERED, "UNREGISTER"},
269 {DEVFSD_NOTIFY_ASYNC_OPEN, "ASYNC_OPEN"},
270 {DEVFSD_NOTIFY_CLOSE, "CLOSE"},
271 {DEVFSD_NOTIFY_LOOKUP, "LOOKUP"},
272 {DEVFSD_NOTIFY_CHANGE, "CHANGE"},
273 {DEVFSD_NOTIFY_CREATE, "CREATE"},
274 {DEVFSD_NOTIFY_DELETE, "DELETE"},
275 {0xffffffff, NULL}
276};
277
278/* Busybox messages */
279
280static const char bb_msg_proto_rev[] ALIGN1 = "protocol revision";
281static const char bb_msg_bad_config[] ALIGN1 = "bad %s config file: %s";
282static const char bb_msg_small_buffer[] ALIGN1 = "buffer too small";
283static const char bb_msg_variable_not_found[] ALIGN1 = "variable: %s not found";
284
285/* Busybox stuff */
286#if ENABLE_DEVFSD_VERBOSE || ENABLE_DEBUG
287#define info_logger(p, fmt, args...) bb_info_msg(fmt, ## args)
288#define msg_logger(p, fmt, args...) bb_error_msg(fmt, ## args)
289#define msg_logger_and_die(p, fmt, args...) bb_error_msg_and_die(fmt, ## args)
290#define error_logger(p, fmt, args...) bb_perror_msg(fmt, ## args)
291#define error_logger_and_die(p, fmt, args...) bb_perror_msg_and_die(fmt, ## args)
292#else
293#define info_logger(p, fmt, args...)
294#define msg_logger(p, fmt, args...)
295#define msg_logger_and_die(p, fmt, args...) exit(EXIT_FAILURE)
296#define error_logger(p, fmt, args...)
297#define error_logger_and_die(p, fmt, args...) exit(EXIT_FAILURE)
298#endif
299
300static void safe_memcpy(char *dest, const char *src, int len)
301{
302 memcpy(dest , src, len);
303 dest[len] = '\0';
304}
305
306static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, const char *ptr)
307{
308 if (d[n - 4] == 'd' && d[n - 3] == 'i' && d[n - 2] == 's' && d[n - 1] == 'c')
309 return 2 + addendum;
310 if (d[n - 2] == 'c' && d[n - 1] == 'd')
311 return 3 + addendum;
312 if (ptr[0] == 'p' && ptr[1] == 'a' && ptr[2] == 'r' && ptr[3] == 't')
313 return 4 + addendum;
314 if (ptr[n - 2] == 'm' && ptr[n - 1] == 't')
315 return 5 + addendum;
316 return 0;
317}
318
319static unsigned int scan_dev_name(const char *d, unsigned int n, const char *ptr)
320{
321 if (d[0] == 's' && d[1] == 'c' && d[2] == 's' && d[3] == 'i' && d[4] == '/') {
322 if (d[n - 7] == 'g' && d[n - 6] == 'e' && d[n - 5] == 'n'
323 && d[n - 4] == 'e' && d[n - 3] == 'r' && d[n - 2] == 'i' && d[n - 1] == 'c'
324 )
325 return 1;
326 return scan_dev_name_common(d, n, 0, ptr);
327 }
328 if (d[0] == 'i' && d[1] == 'd' && d[2] == 'e' && d[3] == '/'
329 && d[4] == 'h' && d[5] == 'o' && d[6] == 's' && d[7] == 't'
330 )
331 return scan_dev_name_common(d, n, 4, ptr);
332 if (d[0] == 's' && d[1] == 'b' && d[2] == 'p' && d[3] == '/')
333 return 10;
334 if (d[0] == 'v' && d[1] == 'c' && d[2] == 'c' && d[3] == '/')
335 return 11;
336 if (d[0] == 'p' && d[1] == 't' && d[2] == 'y' && d[3] == '/')
337 return 12;
338 return 0;
339}
340
341/* Public functions follow */
342
343int devfsd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
344int devfsd_main(int argc, char **argv)
345{
346 int print_version = FALSE;
347 int do_daemon = TRUE;
348 int no_polling = FALSE;
349 int do_scan;
350 int fd, proto_rev, count;
351 unsigned long event_mask = 0;
352 struct sigaction new_action;
353 struct initial_symlink_struct *curr;
354
355 if (argc < 2)
356 bb_show_usage();
357
358 for (count = 2; count < argc; ++count) {
359 if (argv[count][0] == '-') {
360 if (argv[count][1] == 'v' && !argv[count][2]) /* -v */
361 print_version = TRUE;
362 else if (ENABLE_DEVFSD_FG_NP && argv[count][1] == 'f'
363 && argv[count][2] == 'g' && !argv[count][3]) /* -fg */
364 do_daemon = FALSE;
365 else if (ENABLE_DEVFSD_FG_NP && argv[count][1] == 'n'
366 && argv[count][2] == 'p' && !argv[count][3]) /* -np */
367 no_polling = TRUE;
368 else
369 bb_show_usage();
370 }
371 }
372
373 mount_point = bb_simplify_path(argv[1]);
374
375 xchdir(mount_point);
376
377 fd = xopen(".devfsd", O_RDONLY);
378 close_on_exec_on(fd);
379 xioctl(fd, DEVFSDIOC_GET_PROTO_REV, &proto_rev);
380
381 /*setup initial entries */
382 for (curr = initial_symlinks; curr->dest != NULL; ++curr)
383 symlink(curr->dest, curr->name);
384
385 /* NB: The check for CONFIG_FILE is done in read_config_file() */
386
387 if (print_version || (DEVFSD_PROTOCOL_REVISION_DAEMON != proto_rev)) {
388 printf("%s v%s\nDaemon %s:\t%d\nKernel-side %s:\t%d\n",
389 applet_name, DEVFSD_VERSION, bb_msg_proto_rev,
390 DEVFSD_PROTOCOL_REVISION_DAEMON, bb_msg_proto_rev, proto_rev);
391 if (DEVFSD_PROTOCOL_REVISION_DAEMON != proto_rev)
392 bb_error_msg_and_die("%s mismatch!", bb_msg_proto_rev);
393 exit(EXIT_SUCCESS); /* -v */
394 }
395 /* Tell kernel we are special(i.e. we get to see hidden entries) */
396 xioctl(fd, DEVFSDIOC_SET_EVENT_MASK, 0);
397
398 /* Set up SIGHUP and SIGUSR1 handlers */
399 sigemptyset(&new_action.sa_mask);
400 new_action.sa_flags = 0;
401 new_action.sa_handler = signal_handler;
402 sigaction_set(SIGHUP, &new_action);
403 sigaction_set(SIGUSR1, &new_action);
404
405 printf("%s v%s started for %s\n", applet_name, DEVFSD_VERSION, mount_point);
406
407 /* Set umask so that mknod(2), open(2) and mkdir(2) have complete control over permissions */
408 umask(0);
409 read_config_file((char*)CONFIG_FILE, FALSE, &event_mask);
410 /* Do the scan before forking, so that boot scripts see the finished product */
411 dir_operation(SERVICE, mount_point, 0, NULL);
412
413 if (ENABLE_DEVFSD_FG_NP && no_polling)
414 exit(EXIT_SUCCESS);
415
416 if (ENABLE_DEVFSD_VERBOSE || ENABLE_DEBUG)
417 logmode = LOGMODE_BOTH;
418 else if (do_daemon == TRUE)
419 logmode = LOGMODE_SYSLOG;
420 /* This is the default */
421 /*else
422 logmode = LOGMODE_STDIO; */
423
424 if (do_daemon) {
425 /* Release so that the child can grab it */
426 xioctl(fd, DEVFSDIOC_RELEASE_EVENT_QUEUE, 0);
427 bb_daemonize_or_rexec(0, argv);
428 } else if (ENABLE_DEVFSD_FG_NP) {
429 setpgid(0, 0); /* Become process group leader */
430 }
431
432 while (TRUE) {
433 do_scan = do_servicing(fd, event_mask);
434
435 free_config();
436 read_config_file((char*)CONFIG_FILE, FALSE, &event_mask);
437 if (do_scan)
438 dir_operation(SERVICE, mount_point, 0, NULL);
439 }
440 if (ENABLE_FEATURE_CLEAN_UP) free(mount_point);
441} /* End Function main */
442
443
444/* Private functions follow */
445
446static void read_config_file(char *path, int optional, unsigned long *event_mask)
447/* [SUMMARY] Read a configuration database.
448 <path> The path to read the database from. If this is a directory, all
449 entries in that directory will be read(except hidden entries).
450 <optional> If TRUE, the routine will silently ignore a missing config file.
451 <event_mask> The event mask is written here. This is not initialised.
452 [RETURNS] Nothing.
453*/
454{
455 struct stat statbuf;
456 FILE *fp;
457 char buf[STRING_LENGTH];
458 char *line = NULL;
459 char *p;
460
461 if (stat(path, &statbuf) == 0) {
462 /* Don't read 0 length files: ignored */
463 /*if (statbuf.st_size == 0)
464 return;*/
465 if (S_ISDIR(statbuf.st_mode)) {
466 p = bb_simplify_path(path);
467 dir_operation(READ_CONFIG, p, 0, event_mask);
468 free(p);
469 return;
470 }
471 fp = fopen_for_read(path);
472 if (fp != NULL) {
473 while (fgets(buf, STRING_LENGTH, fp) != NULL) {
474 /* Skip whitespace */
475 line = buf;
476 line = skip_whitespace(line);
477 if (line[0] == '\0' || line[0] == '#')
478 continue;
479 process_config_line(line, event_mask);
480 }
481 fclose(fp);
482 } else {
483 goto read_config_file_err;
484 }
485 } else {
486read_config_file_err:
487 if (optional == 0 && errno == ENOENT)
488 error_logger_and_die(LOG_ERR, "read config file: %s", path);
489 }
490} /* End Function read_config_file */
491
492static void process_config_line(const char *line, unsigned long *event_mask)
493/* [SUMMARY] Process a line from a configuration file.
494 <line> The configuration line.
495 <event_mask> The event mask is written here. This is not initialised.
496 [RETURNS] Nothing.
497*/
498{
499 int num_args, count;
500 struct config_entry_struct *new;
501 char p[MAX_ARGS][STRING_LENGTH];
502 char when[STRING_LENGTH], what[STRING_LENGTH];
503 char name[STRING_LENGTH];
504 const char *msg = "";
505 char *ptr;
506 int i;
507
508 /* !!!! Only Uppercase Keywords in devsfd.conf */
509 static const char options[] ALIGN1 =
510 "CLEAR_CONFIG\0""INCLUDE\0""OPTIONAL_INCLUDE\0"
511 "RESTORE\0""PERMISSIONS\0""MODLOAD\0""EXECUTE\0"
512 "COPY\0""IGNORE\0""MKOLDCOMPAT\0""MKNEWCOMPAT\0"
513 "RMOLDCOMPAT\0""RMNEWCOMPAT\0";
514
515 for (count = 0; count < MAX_ARGS; ++count)
516 p[count][0] = '\0';
517 num_args = sscanf(line, "%s %s %s %s %s %s %s %s %s %s",
518 when, name, what,
519 p[0], p[1], p[2], p[3], p[4], p[5], p[6]);
520
521 i = index_in_strings(options, when);
522
523 /* "CLEAR_CONFIG" */
524 if (i == 0) {
525 free_config();
526 *event_mask = 0;
527 return;
528 }
529
530 if (num_args < 2)
531 goto process_config_line_err;
532
533 /* "INCLUDE" & "OPTIONAL_INCLUDE" */
534 if (i == 1 || i == 2) {
535 st_expr_expand(name, STRING_LENGTH, name, get_variable, NULL);
536 info_logger(LOG_INFO, "%sinclude: %s", (toupper(when[0]) == 'I') ? "": "optional_", name);
537 read_config_file(name, (toupper(when[0]) == 'I') ? FALSE : TRUE, event_mask);
538 return;
539 }
540 /* "RESTORE" */
541 if (i == 3) {
542 dir_operation(RESTORE, name, strlen(name),NULL);
543 return;
544 }
545 if (num_args < 3)
546 goto process_config_line_err;
547
548 new = xzalloc(sizeof *new);
549
550 for (count = 0; event_types[count].config_name != NULL; ++count) {
551 if (strcasecmp(when, event_types[count].config_name) != 0)
552 continue;
553 new->action.when = event_types[count].type;
554 break;
555 }
556 if (event_types[count].config_name == NULL) {
557 msg = "WHEN in";
558 goto process_config_line_err;
559 }
560
561 i = index_in_strings(options, what);
562
563 switch (i) {
564 case 4: /* "PERMISSIONS" */
565 new->action.what = AC_PERMISSIONS;
566 /* Get user and group */
567 ptr = strchr(p[0], '.');
568 if (ptr == NULL) {
569 msg = "UID.GID";
570 goto process_config_line_err; /*"missing '.' in UID.GID"*/
571 }
572
573 *ptr++ = '\0';
574 new->u.permissions.uid = get_uid_gid(UID, p[0]);
575 new->u.permissions.gid = get_uid_gid(GID, ptr);
576 /* Get mode */
577 new->u.permissions.mode = get_mode(p[1]);
578 break;
579 case 5: /* MODLOAD */
580 /*This action will pass "/dev/$devname"(i.e. "/dev/" prefixed to
581 the device name) to the module loading facility. In addition,
582 the /etc/modules.devfs configuration file is used.*/
583 if (ENABLE_DEVFSD_MODLOAD)
584 new->action.what = AC_MODLOAD;
585 break;
586 case 6: /* EXECUTE */
587 new->action.what = AC_EXECUTE;
588 num_args -= 3;
589
590 for (count = 0; count < num_args; ++count)
591 new->u.execute.argv[count] = xstrdup(p[count]);
592
593 new->u.execute.argv[num_args] = NULL;
594 break;
595 case 7: /* COPY */
596 new->action.what = AC_COPY;
597 num_args -= 3;
598 if (num_args != 2)
599 goto process_config_line_err; /* missing path and function in line */
600
601 new->u.copy.source = xstrdup(p[0]);
602 new->u.copy.destination = xstrdup(p[1]);
603 break;
604 case 8: /* IGNORE */
605 /* FALLTROUGH */
606 case 9: /* MKOLDCOMPAT */
607 /* FALLTROUGH */
608 case 10: /* MKNEWCOMPAT */
609 /* FALLTROUGH */
610 case 11:/* RMOLDCOMPAT */
611 /* FALLTROUGH */
612 case 12: /* RMNEWCOMPAT */
613 /* AC_IGNORE 6
614 AC_MKOLDCOMPAT 7
615 AC_MKNEWCOMPAT 8
616 AC_RMOLDCOMPAT 9
617 AC_RMNEWCOMPAT 10*/
618 new->action.what = i - 2;
619 break;
620 default:
621 msg = "WHAT in";
622 goto process_config_line_err;
623 /*esac*/
624 } /* switch (i) */
625
626 xregcomp(&new->preg, name, REG_EXTENDED);
627
628 *event_mask |= 1 << new->action.when;
629 new->next = NULL;
630 if (first_config == NULL)
631 first_config = new;
632 else
633 last_config->next = new;
634 last_config = new;
635 return;
636
637 process_config_line_err:
638 msg_logger_and_die(LOG_ERR, bb_msg_bad_config, msg , line);
639} /* End Function process_config_line */
640
641static int do_servicing(int fd, unsigned long event_mask)
642/* [SUMMARY] Service devfs changes until a signal is received.
643 <fd> The open control file.
644 <event_mask> The event mask.
645 [RETURNS] TRUE if SIGHUP was caught, else FALSE.
646*/
647{
648 ssize_t bytes;
649 struct devfsd_notify_struct info;
650
651 /* (void*) cast is only in order to match prototype */
652 xioctl(fd, DEVFSDIOC_SET_EVENT_MASK, (void*)event_mask);
653 while (!caught_signal) {
654 errno = 0;
655 bytes = read(fd, (char *) &info, sizeof info);
656 if (caught_signal)
657 break; /* Must test for this first */
658 if (errno == EINTR)
659 continue; /* Yes, the order is important */
660 if (bytes < 1)
661 break;
662 service_name(&info);
663 }
664 if (caught_signal) {
665 int c_sighup = caught_sighup;
666
667 caught_signal = FALSE;
668 caught_sighup = FALSE;
669 return c_sighup;
670 }
671 msg_logger_and_die(LOG_ERR, "read error on control file");
672} /* End Function do_servicing */
673
674static void service_name(const struct devfsd_notify_struct *info)
675/* [SUMMARY] Service a single devfs change.
676 <info> The devfs change.
677 [RETURNS] Nothing.
678*/
679{
680 unsigned int n;
681 regmatch_t mbuf[MAX_SUBEXPR];
682 struct config_entry_struct *entry;
683
684 if (ENABLE_DEBUG && info->overrun_count > 0)
685 msg_logger(LOG_ERR, "lost %u events", info->overrun_count);
686
687 /* Discard lookups on "/dev/log" and "/dev/initctl" */
688 if (info->type == DEVFSD_NOTIFY_LOOKUP
689 && ((info->devname[0] == 'l' && info->devname[1] == 'o'
690 && info->devname[2] == 'g' && !info->devname[3])
691 || (info->devname[0] == 'i' && info->devname[1] == 'n'
692 && info->devname[2] == 'i' && info->devname[3] == 't'
693 && info->devname[4] == 'c' && info->devname[5] == 't'
694 && info->devname[6] == 'l' && !info->devname[7]))
695 )
696 return;
697
698 for (entry = first_config; entry != NULL; entry = entry->next) {
699 /* First check if action matches the type, then check if name matches */
700 if (info->type != entry->action.when
701 || regexec(&entry->preg, info->devname, MAX_SUBEXPR, mbuf, 0) != 0)
702 continue;
703 for (n = 0;(n < MAX_SUBEXPR) && (mbuf[n].rm_so != -1); ++n)
704 /* VOID */;
705
706 switch (entry->action.what) {
707 case AC_PERMISSIONS:
708 action_permissions(info, entry);
709 break;
710 case AC_MODLOAD:
711 if (ENABLE_DEVFSD_MODLOAD)
712 action_modload(info, entry);
713 break;
714 case AC_EXECUTE:
715 action_execute(info, entry, mbuf, n);
716 break;
717 case AC_COPY:
718 action_copy(info, entry, mbuf, n);
719 break;
720 case AC_IGNORE:
721 return;
722 /*break;*/
723 case AC_MKOLDCOMPAT:
724 case AC_MKNEWCOMPAT:
725 case AC_RMOLDCOMPAT:
726 case AC_RMNEWCOMPAT:
727 action_compat(info, entry->action.what);
728 break;
729 default:
730 msg_logger_and_die(LOG_ERR, "Unknown action");
731 }
732 }
733} /* End Function service_name */
734
735static void action_permissions(const struct devfsd_notify_struct *info,
736 const struct config_entry_struct *entry)
737/* [SUMMARY] Update permissions for a device entry.
738 <info> The devfs change.
739 <entry> The config file entry.
740 [RETURNS] Nothing.
741*/
742{
743 struct stat statbuf;
744
745 if (stat(info->devname, &statbuf) != 0
746 || chmod(info->devname, (statbuf.st_mode & S_IFMT) | (entry->u.permissions.mode & ~S_IFMT)) != 0
747 || chown(info->devname, entry->u.permissions.uid, entry->u.permissions.gid) != 0
748 )
749 error_logger(LOG_ERR, "Can't chmod or chown: %s", info->devname);
750} /* End Function action_permissions */
751
752static void action_modload(const struct devfsd_notify_struct *info,
753 const struct config_entry_struct *entry UNUSED_PARAM)
754/* [SUMMARY] Load a module.
755 <info> The devfs change.
756 <entry> The config file entry.
757 [RETURNS] Nothing.
758*/
759{
760 char *argv[6];
761
762 argv[0] = (char*)MODPROBE;
763 argv[1] = (char*)MODPROBE_SWITCH_1; /* "-k" */
764 argv[2] = (char*)MODPROBE_SWITCH_2; /* "-C" */
765 argv[3] = (char*)CONFIG_MODULES_DEVFS;
766 argv[4] = concat_path_file("/dev", info->devname); /* device */
767 argv[5] = NULL;
768
769 spawn_and_wait(argv);
770 free(argv[4]);
771} /* End Function action_modload */
772
773static void action_execute(const struct devfsd_notify_struct *info,
774 const struct config_entry_struct *entry,
775 const regmatch_t *regexpr, unsigned int numexpr)
776/* [SUMMARY] Execute a programme.
777 <info> The devfs change.
778 <entry> The config file entry.
779 <regexpr> The number of subexpression(start, end) offsets within the
780 device name.
781 <numexpr> The number of elements within <<regexpr>>.
782 [RETURNS] Nothing.
783*/
784{
785 unsigned int count;
786 struct get_variable_info gv_info;
787 char *argv[MAX_ARGS + 1];
788 char largv[MAX_ARGS + 1][STRING_LENGTH];
789
790 gv_info.info = info;
791 gv_info.devname = info->devname;
792 snprintf(gv_info.devpath, sizeof(gv_info.devpath), "%s/%s", mount_point, info->devname);
793 for (count = 0; entry->u.execute.argv[count] != NULL; ++count) {
794 expand_expression(largv[count], STRING_LENGTH,
795 entry->u.execute.argv[count],
796 get_variable, &gv_info,
797 gv_info.devname, regexpr, numexpr);
798 argv[count] = largv[count];
799 }
800 argv[count] = NULL;
801 spawn_and_wait(argv);
802} /* End Function action_execute */
803
804
805static void action_copy(const struct devfsd_notify_struct *info,
806 const struct config_entry_struct *entry,
807 const regmatch_t *regexpr, unsigned int numexpr)
808/* [SUMMARY] Copy permissions.
809 <info> The devfs change.
810 <entry> The config file entry.
811 <regexpr> This list of subexpression(start, end) offsets within the
812 device name.
813 <numexpr> The number of elements in <<regexpr>>.
814 [RETURNS] Nothing.
815*/
816{
817 mode_t new_mode;
818 struct get_variable_info gv_info;
819 struct stat source_stat, dest_stat;
820 char source[STRING_LENGTH], destination[STRING_LENGTH];
821 int ret = 0;
822
823 dest_stat.st_mode = 0;
824
825 if ((info->type == DEVFSD_NOTIFY_CHANGE) && S_ISLNK(info->mode))
826 return;
827 gv_info.info = info;
828 gv_info.devname = info->devname;
829
830 snprintf(gv_info.devpath, sizeof(gv_info.devpath), "%s/%s", mount_point, info->devname);
831 expand_expression(source, STRING_LENGTH, entry->u.copy.source,
832 get_variable, &gv_info, gv_info.devname,
833 regexpr, numexpr);
834
835 expand_expression(destination, STRING_LENGTH, entry->u.copy.destination,
836 get_variable, &gv_info, gv_info.devname,
837 regexpr, numexpr);
838
839 if (!make_dir_tree(destination) || lstat(source, &source_stat) != 0)
840 return;
841 lstat(destination, &dest_stat);
842 new_mode = source_stat.st_mode & ~S_ISVTX;
843 if (info->type == DEVFSD_NOTIFY_CREATE)
844 new_mode |= S_ISVTX;
845 else if ((info->type == DEVFSD_NOTIFY_CHANGE) &&(dest_stat.st_mode & S_ISVTX))
846 new_mode |= S_ISVTX;
847 ret = copy_inode(destination, &dest_stat, new_mode, source, &source_stat);
848 if (ENABLE_DEBUG && ret && (errno != EEXIST))
849 error_logger(LOG_ERR, "copy_inode: %s to %s", source, destination);
850} /* End Function action_copy */
851
852static void action_compat(const struct devfsd_notify_struct *info, unsigned int action)
853/* [SUMMARY] Process a compatibility request.
854 <info> The devfs change.
855 <action> The action to take.
856 [RETURNS] Nothing.
857*/
858{
859 int ret;
860 const char *compat_name = NULL;
861 const char *dest_name = info->devname;
862 const char *ptr;
863 char compat_buf[STRING_LENGTH], dest_buf[STRING_LENGTH];
864 int mode, host, bus, target, lun;
865 unsigned int i;
866 char rewind_;
867 /* 1 to 5 "scsi/" , 6 to 9 "ide/host" */
868 static const char *const fmt[] = {
869 NULL ,
870 "sg/c%db%dt%du%d", /* scsi/generic */
871 "sd/c%db%dt%du%d", /* scsi/disc */
872 "sr/c%db%dt%du%d", /* scsi/cd */
873 "sd/c%db%dt%du%dp%d", /* scsi/part */
874 "st/c%db%dt%du%dm%d%c", /* scsi/mt */
875 "ide/hd/c%db%dt%du%d", /* ide/host/disc */
876 "ide/cd/c%db%dt%du%d", /* ide/host/cd */
877 "ide/hd/c%db%dt%du%dp%d", /* ide/host/part */
878 "ide/mt/c%db%dt%du%d%s", /* ide/host/mt */
879 NULL
880 };
881
882 /* First construct compatibility name */
883 switch (action) {
884 case AC_MKOLDCOMPAT:
885 case AC_RMOLDCOMPAT:
886 compat_name = get_old_name(info->devname, info->namelen, compat_buf, info->major, info->minor);
887 break;
888 case AC_MKNEWCOMPAT:
889 case AC_RMNEWCOMPAT:
890 ptr = bb_basename(info->devname);
891 i = scan_dev_name(info->devname, info->namelen, ptr);
892
893 /* nothing found */
894 if (i == 0 || i > 9)
895 return;
896
897 sscanf(info->devname + ((i < 6) ? 5 : 4), "host%d/bus%d/target%d/lun%d/", &host, &bus, &target, &lun);
898 snprintf(dest_buf, sizeof(dest_buf), "../%s", info->devname + (( i > 5) ? 4 : 0));
899 dest_name = dest_buf;
900 compat_name = compat_buf;
901
902
903 /* 1 == scsi/generic 2 == scsi/disc 3 == scsi/cd 6 == ide/host/disc 7 == ide/host/cd */
904 if (i == 1 || i == 2 || i == 3 || i == 6 || i ==7)
905 sprintf(compat_buf, fmt[i], host, bus, target, lun);
906
907 /* 4 == scsi/part 8 == ide/host/part */
908 if (i == 4 || i == 8)
909 sprintf(compat_buf, fmt[i], host, bus, target, lun, atoi(ptr + 4));
910
911 /* 5 == scsi/mt */
912 if (i == 5) {
913 rewind_ = info->devname[info->namelen - 1];
914 if (rewind_ != 'n')
915 rewind_ = '\0';
916 mode=0;
917 if (ptr[2] == 'l' /*108*/ || ptr[2] == 'm'/*109*/)
918 mode = ptr[2] - 107; /* 1 or 2 */
919 if (ptr[2] == 'a')
920 mode = 3;
921 sprintf(compat_buf, fmt[i], host, bus, target, lun, mode, rewind_);
922 }
923
924 /* 9 == ide/host/mt */
925 if (i == 9)
926 snprintf(compat_buf, sizeof(compat_buf), fmt[i], host, bus, target, lun, ptr + 2);
927 /* esac */
928 } /* switch (action) */
929
930 if (compat_name == NULL)
931 return;
932
933 /* Now decide what to do with it */
934 switch (action) {
935 case AC_MKOLDCOMPAT:
936 case AC_MKNEWCOMPAT:
937 mksymlink(dest_name, compat_name);
938 break;
939 case AC_RMOLDCOMPAT:
940 case AC_RMNEWCOMPAT:
941 ret = unlink(compat_name);
942 if (ENABLE_DEBUG && ret)
943 error_logger(LOG_ERR, "unlink: %s", compat_name);
944 break;
945 /*esac*/
946 } /* switch (action) */
947} /* End Function action_compat */
948
949static void restore(char *spath, struct stat source_stat, int rootlen)
950{
951 char *dpath;
952 struct stat dest_stat;
953
954 dest_stat.st_mode = 0;
955 dpath = concat_path_file(mount_point, spath + rootlen);
956 lstat(dpath, &dest_stat);
957 free(dpath);
958 if (S_ISLNK(source_stat.st_mode) || (source_stat.st_mode & S_ISVTX))
959 copy_inode(dpath, &dest_stat, (source_stat.st_mode & ~S_ISVTX), spath, &source_stat);
960
961 if (S_ISDIR(source_stat.st_mode))
962 dir_operation(RESTORE, spath, rootlen, NULL);
963}
964
965
966static int copy_inode(const char *destpath, const struct stat *dest_stat,
967 mode_t new_mode,
968 const char *sourcepath, const struct stat *source_stat)
969/* [SUMMARY] Copy an inode.
970 <destpath> The destination path. An existing inode may be deleted.
971 <dest_stat> The destination stat(2) information.
972 <new_mode> The desired new mode for the destination.
973 <sourcepath> The source path.
974 <source_stat> The source stat(2) information.
975 [RETURNS] TRUE on success, else FALSE.
976*/
977{
978 int source_len, dest_len;
979 char source_link[STRING_LENGTH], dest_link[STRING_LENGTH];
980 int fd, val;
981 struct sockaddr_un un_addr;
982 char symlink_val[STRING_LENGTH];
983
984 if ((source_stat->st_mode & S_IFMT) ==(dest_stat->st_mode & S_IFMT)) {
985 /* Same type */
986 if (S_ISLNK(source_stat->st_mode)) {
987 source_len = readlink(sourcepath, source_link, STRING_LENGTH - 1);
988 if ((source_len < 0)
989 || (dest_len = readlink(destpath, dest_link, STRING_LENGTH - 1)) < 0
990 )
991 return FALSE;
992 source_link[source_len] = '\0';
993 dest_link[dest_len] = '\0';
994 if ((source_len != dest_len) || (strcmp(source_link, dest_link) != 0)) {
995 unlink(destpath);
996 symlink(source_link, destpath);
997 }
998 return TRUE;
999 } /* Else not a symlink */
1000 chmod(destpath, new_mode & ~S_IFMT);
1001 chown(destpath, source_stat->st_uid, source_stat->st_gid);
1002 return TRUE;
1003 }
1004 /* Different types: unlink and create */
1005 unlink(destpath);
1006 switch (source_stat->st_mode & S_IFMT) {
1007 case S_IFSOCK:
1008 fd = socket(AF_UNIX, SOCK_STREAM, 0);
1009 if (fd < 0)
1010 break;
1011 un_addr.sun_family = AF_UNIX;
1012 snprintf(un_addr.sun_path, sizeof(un_addr.sun_path), "%s", destpath);
1013 val = bind(fd, (struct sockaddr *) &un_addr, (int) sizeof un_addr);
1014 close(fd);
1015 if (val != 0 || chmod(destpath, new_mode & ~S_IFMT) != 0)
1016 break;
1017 goto do_chown;
1018 case S_IFLNK:
1019 val = readlink(sourcepath, symlink_val, STRING_LENGTH - 1);
1020 if (val < 0)
1021 break;
1022 symlink_val[val] = '\0';
1023 if (symlink(symlink_val, destpath) == 0)
1024 return TRUE;
1025 break;
1026 case S_IFREG:
1027 fd = open(destpath, O_RDONLY | O_CREAT, new_mode & ~S_IFMT);
1028 if (fd < 0)
1029 break;
1030 close(fd);
1031 if (chmod(destpath, new_mode & ~S_IFMT) != 0)
1032 break;
1033 goto do_chown;
1034 case S_IFBLK:
1035 case S_IFCHR:
1036 case S_IFIFO:
1037 if (mknod(destpath, new_mode, source_stat->st_rdev) != 0)
1038 break;
1039 goto do_chown;
1040 case S_IFDIR:
1041 if (mkdir(destpath, new_mode & ~S_IFMT) != 0)
1042 break;
1043do_chown:
1044 if (chown(destpath, source_stat->st_uid, source_stat->st_gid) == 0)
1045 return TRUE;
1046 /*break;*/
1047 }
1048 return FALSE;
1049} /* End Function copy_inode */
1050
1051static void free_config(void)
1052/* [SUMMARY] Free the configuration information.
1053 [RETURNS] Nothing.
1054*/
1055{
1056 struct config_entry_struct *c_entry;
1057 void *next;
1058
1059 for (c_entry = first_config; c_entry != NULL; c_entry = next) {
1060 unsigned int count;
1061
1062 next = c_entry->next;
1063 regfree(&c_entry->preg);
1064 if (c_entry->action.what == AC_EXECUTE) {
1065 for (count = 0; count < MAX_ARGS; ++count) {
1066 if (c_entry->u.execute.argv[count] == NULL)
1067 break;
1068 free(c_entry->u.execute.argv[count]);
1069 }
1070 }
1071 free(c_entry);
1072 }
1073 first_config = NULL;
1074 last_config = NULL;
1075} /* End Function free_config */
1076
1077static int get_uid_gid(int flag, const char *string)
1078/* [SUMMARY] Convert a string to a UID or GID value.
1079 <flag> "UID" or "GID".
1080 <string> The string.
1081 [RETURNS] The UID or GID value.
1082*/
1083{
1084 struct passwd *pw_ent;
1085 struct group *grp_ent;
1086 const char *msg;
1087
1088 if (isdigit(string[0]) || ((string[0] == '-') && isdigit(string[1])))
1089 return atoi(string);
1090
1091 if (flag == UID && (pw_ent = getpwnam(string)) != NULL)
1092 return pw_ent->pw_uid;
1093
1094 if (ENABLE_DEVFSD_VERBOSE)
1095 msg = "user";
1096
1097 if (flag == GID) {
1098 if ((grp_ent = getgrnam(string)) != NULL)
1099 return grp_ent->gr_gid;
1100 if (ENABLE_DEVFSD_VERBOSE)
1101 msg = "group";
1102 }
1103
1104 if (ENABLE_DEVFSD_VERBOSE)
1105 msg_logger(LOG_ERR, "unknown %s: %s, defaulting to %cid=0", msg, string, msg[0]);
1106 return 0;
1107}/* End Function get_uid_gid */
1108
1109static mode_t get_mode(const char *string)
1110/* [SUMMARY] Convert a string to a mode value.
1111 <string> The string.
1112 [RETURNS] The mode value.
1113*/
1114{
1115 mode_t mode;
1116 int i;
1117
1118 if (isdigit(string[0]))
1119 return strtoul(string, NULL, 8);
1120 if (strlen(string) != 9)
1121 msg_logger_and_die(LOG_ERR, "bad mode: %s", string);
1122
1123 mode = 0;
1124 i = S_IRUSR;
1125 while (i > 0) {
1126 if (string[0] == 'r' || string[0] == 'w' || string[0] == 'x')
1127 mode += i;
1128 i = i / 2;
1129 string++;
1130 }
1131 return mode;
1132} /* End Function get_mode */
1133
1134static void signal_handler(int sig)
1135{
1136 caught_signal = TRUE;
1137 if (sig == SIGHUP)
1138 caught_sighup = TRUE;
1139
1140 info_logger(LOG_INFO, "Caught signal %d", sig);
1141} /* End Function signal_handler */
1142
1143static const char *get_variable(const char *variable, void *info)
1144{
1145 static char sbuf[sizeof(int)*3 + 2]; /* sign and NUL */
1146 static char *hostname;
1147
1148 struct get_variable_info *gv_info = info;
1149 const char *field_names[] = {
1150 "hostname", "mntpt", "devpath", "devname",
1151 "uid", "gid", "mode", hostname, mount_point,
1152 gv_info->devpath, gv_info->devname, NULL
1153 };
1154 int i;
1155
1156 if (!hostname)
1157 hostname = safe_gethostname();
1158 /* index_in_str_array returns i>=0 */
1159 i = index_in_str_array(field_names, variable);
1160
1161 if (i > 6 || i < 0 || (i > 1 && gv_info == NULL))
1162 return NULL;
1163 if (i >= 0 && i <= 3)
1164 return field_names[i + 7];
1165
1166 if (i == 4)
1167 sprintf(sbuf, "%u", gv_info->info->uid);
1168 else if (i == 5)
1169 sprintf(sbuf, "%u", gv_info->info->gid);
1170 else if (i == 6)
1171 sprintf(sbuf, "%o", gv_info->info->mode);
1172 return sbuf;
1173} /* End Function get_variable */
1174
1175static void service(struct stat statbuf, char *path)
1176{
1177 struct devfsd_notify_struct info;
1178
1179 memset(&info, 0, sizeof info);
1180 info.type = DEVFSD_NOTIFY_REGISTERED;
1181 info.mode = statbuf.st_mode;
1182 info.major = major(statbuf.st_rdev);
1183 info.minor = minor(statbuf.st_rdev);
1184 info.uid = statbuf.st_uid;
1185 info.gid = statbuf.st_gid;
1186 snprintf(info.devname, sizeof(info.devname), "%s", path + strlen(mount_point) + 1);
1187 info.namelen = strlen(info.devname);
1188 service_name(&info);
1189 if (S_ISDIR(statbuf.st_mode))
1190 dir_operation(SERVICE, path, 0, NULL);
1191}
1192
1193static void dir_operation(int type, const char * dir_name, int var, unsigned long *event_mask)
1194/* [SUMMARY] Scan a directory tree and generate register events on leaf nodes.
1195 <flag> To choose which function to perform
1196 <dp> The directory pointer. This is closed upon completion.
1197 <dir_name> The name of the directory.
1198 <rootlen> string length parameter.
1199 [RETURNS] Nothing.
1200*/
1201{
1202 struct stat statbuf;
1203 DIR *dp;
1204 struct dirent *de;
1205 char *path;
1206
1207 dp = warn_opendir(dir_name);
1208 if (dp == NULL)
1209 return;
1210
1211 while ((de = readdir(dp)) != NULL) {
1212
1213 if (de->d_name && DOT_OR_DOTDOT(de->d_name))
1214 continue;
1215 path = concat_path_file(dir_name, de->d_name);
1216 if (lstat(path, &statbuf) == 0) {
1217 switch (type) {
1218 case SERVICE:
1219 service(statbuf, path);
1220 break;
1221 case RESTORE:
1222 restore(path, statbuf, var);
1223 break;
1224 case READ_CONFIG:
1225 read_config_file(path, var, event_mask);
1226 break;
1227 }
1228 }
1229 free(path);
1230 }
1231 closedir(dp);
1232} /* End Function do_scan_and_service */
1233
1234static int mksymlink(const char *oldpath, const char *newpath)
1235/* [SUMMARY] Create a symlink, creating intervening directories as required.
1236 <oldpath> The string contained in the symlink.
1237 <newpath> The name of the new symlink.
1238 [RETURNS] 0 on success, else -1.
1239*/
1240{
1241 if (!make_dir_tree(newpath))
1242 return -1;
1243
1244 if (symlink(oldpath, newpath) != 0) {
1245 if (errno != EEXIST)
1246 return -1;
1247 }
1248 return 0;
1249} /* End Function mksymlink */
1250
1251
1252static int make_dir_tree(const char *path)
1253/* [SUMMARY] Creating intervening directories for a path as required.
1254 <path> The full pathname(including the leaf node).
1255 [RETURNS] TRUE on success, else FALSE.
1256*/
1257{
1258 if (bb_make_directory(dirname((char *)path), -1, FILEUTILS_RECUR) == -1)
1259 return FALSE;
1260 return TRUE;
1261} /* End Function make_dir_tree */
1262
1263static int expand_expression(char *output, unsigned int outsize,
1264 const char *input,
1265 const char *(*get_variable_func)(const char *variable, void *info),
1266 void *info,
1267 const char *devname,
1268 const regmatch_t *ex, unsigned int numexp)
1269/* [SUMMARY] Expand environment variables and regular subexpressions in string.
1270 <output> The output expanded expression is written here.
1271 <length> The size of the output buffer.
1272 <input> The input expression. This may equal <<output>>.
1273 <get_variable> A function which will be used to get variable values. If
1274 this returns NULL, the environment is searched instead. If this is NULL,
1275 only the environment is searched.
1276 <info> An arbitrary pointer passed to <<get_variable>>.
1277 <devname> Device name; specifically, this is the string that contains all
1278 of the regular subexpressions.
1279 <ex> Array of start / end offsets into info->devname for each subexpression
1280 <numexp> Number of regular subexpressions found in <<devname>>.
1281 [RETURNS] TRUE on success, else FALSE.
1282*/
1283{
1284 char temp[STRING_LENGTH];
1285
1286 if (!st_expr_expand(temp, STRING_LENGTH, input, get_variable_func, info))
1287 return FALSE;
1288 expand_regexp(output, outsize, temp, devname, ex, numexp);
1289 return TRUE;
1290} /* End Function expand_expression */
1291
1292static void expand_regexp(char *output, size_t outsize, const char *input,
1293 const char *devname,
1294 const regmatch_t *ex, unsigned int numex)
1295/* [SUMMARY] Expand all occurrences of the regular subexpressions \0 to \9.
1296 <output> The output expanded expression is written here.
1297 <outsize> The size of the output buffer.
1298 <input> The input expression. This may NOT equal <<output>>, because
1299 supporting that would require yet another string-copy. However, it's not
1300 hard to write a simple wrapper function to add this functionality for those
1301 few cases that need it.
1302 <devname> Device name; specifically, this is the string that contains all
1303 of the regular subexpressions.
1304 <ex> An array of start and end offsets into <<devname>>, one for each
1305 subexpression
1306 <numex> Number of subexpressions in the offset-array <<ex>>.
1307 [RETURNS] Nothing.
1308*/
1309{
1310 const char last_exp = '0' - 1 + numex;
1311 int c = -1;
1312
1313 /* Guarantee NULL termination by writing an explicit '\0' character into
1314 the very last byte */
1315 if (outsize)
1316 output[--outsize] = '\0';
1317 /* Copy the input string into the output buffer, replacing '\\' with '\'
1318 and '\0' .. '\9' with subexpressions 0 .. 9, if they exist. Other \x
1319 codes are deleted */
1320 while ((c != '\0') && (outsize != 0)) {
1321 c = *input;
1322 ++input;
1323 if (c == '\\') {
1324 c = *input;
1325 ++input;
1326 if (c != '\\') {
1327 if ((c >= '0') && (c <= last_exp)) {
1328 const regmatch_t *subexp = ex + (c - '0');
1329 unsigned int sublen = subexp->rm_eo - subexp->rm_so;
1330
1331 /* Range checking */
1332 if (sublen > outsize)
1333 sublen = outsize;
1334 strncpy(output, devname + subexp->rm_so, sublen);
1335 output += sublen;
1336 outsize -= sublen;
1337 }
1338 continue;
1339 }
1340 }
1341 *output = c;
1342 ++output;
1343 --outsize;
1344 } /* while */
1345} /* End Function expand_regexp */
1346
1347
1348/* from compat_name.c */
1349
1350struct translate_struct {
1351 const char *match; /* The string to match to(up to length) */
1352 const char *format; /* Format of output, "%s" takes data past match string,
1353 NULL is effectively "%s"(just more efficient) */
1354};
1355
1356static struct translate_struct translate_table[] =
1357{
1358 {"sound/", NULL},
1359 {"printers/", "lp%s"},
1360 {"v4l/", NULL},
1361 {"parports/", "parport%s"},
1362 {"fb/", "fb%s"},
1363 {"netlink/", NULL},
1364 {"loop/", "loop%s"},
1365 {"floppy/", "fd%s"},
1366 {"rd/", "ram%s"},
1367 {"md/", "md%s"}, /* Meta-devices */
1368 {"vc/", "tty%s"},
1369 {"misc/", NULL},
1370 {"isdn/", NULL},
1371 {"pg/", "pg%s"}, /* Parallel port generic ATAPI interface*/
1372 {"i2c/", "i2c-%s"},
1373 {"staliomem/", "staliomem%s"}, /* Stallion serial driver control */
1374 {"tts/E", "ttyE%s"}, /* Stallion serial driver */
1375 {"cua/E", "cue%s"}, /* Stallion serial driver callout */
1376 {"tts/R", "ttyR%s"}, /* Rocketport serial driver */
1377 {"cua/R", "cur%s"}, /* Rocketport serial driver callout */
1378 {"ip2/", "ip2%s"}, /* Computone serial driver control */
1379 {"tts/F", "ttyF%s"}, /* Computone serial driver */
1380 {"cua/F", "cuf%s"}, /* Computone serial driver callout */
1381 {"tts/C", "ttyC%s"}, /* Cyclades serial driver */
1382 {"cua/C", "cub%s"}, /* Cyclades serial driver callout */
1383 {"tts/", "ttyS%s"}, /* Generic serial: must be after others */
1384 {"cua/", "cua%s"}, /* Generic serial: must be after others */
1385 {"input/js", "js%s"}, /* Joystick driver */
1386 {NULL, NULL}
1387};
1388
1389const char *get_old_name(const char *devname, unsigned int namelen,
1390 char *buffer, unsigned int major, unsigned int minor)
1391/* [SUMMARY] Translate a kernel-supplied name into an old name.
1392 <devname> The device name provided by the kernel.
1393 <namelen> The length of the name.
1394 <buffer> A buffer that may be used. This should be at least 128 bytes long.
1395 <major> The major number for the device.
1396 <minor> The minor number for the device.
1397 [RETURNS] A pointer to the old name if known, else NULL.
1398*/
1399{
1400 const char *compat_name = NULL;
1401 const char *ptr;
1402 struct translate_struct *trans;
1403 unsigned int i;
1404 char mode;
1405 int indexx;
1406 const char *pty1;
1407 const char *pty2;
1408 size_t len;
1409 /* 1 to 5 "scsi/" , 6 to 9 "ide/host", 10 sbp/, 11 vcc/, 12 pty/ */
1410 static const char *const fmt[] = {
1411 NULL ,
1412 "sg%u", /* scsi/generic */
1413 NULL, /* scsi/disc */
1414 "sr%u", /* scsi/cd */
1415 NULL, /* scsi/part */
1416 "nst%u%c", /* scsi/mt */
1417 "hd%c" , /* ide/host/disc */
1418 "hd%c" , /* ide/host/cd */
1419 "hd%c%s", /* ide/host/part */
1420 "%sht%d", /* ide/host/mt */
1421 "sbpcd%u", /* sbp/ */
1422 "vcs%s", /* vcc/ */
1423 "%cty%c%c", /* pty/ */
1424 NULL
1425 };
1426
1427 for (trans = translate_table; trans->match != NULL; ++trans) {
1428 len = strlen(trans->match);
1429
1430 if (strncmp(devname, trans->match, len) == 0) {
1431 if (trans->format == NULL)
1432 return devname + len;
1433 sprintf(buffer, trans->format, devname + len);
1434 return buffer;
1435 }
1436 }
1437
1438 ptr = bb_basename(devname);
1439 i = scan_dev_name(devname, namelen, ptr);
1440
1441 if (i > 0 && i < 13)
1442 compat_name = buffer;
1443 else
1444 return NULL;
1445
1446 /* 1 == scsi/generic, 3 == scsi/cd, 10 == sbp/ */
1447 if (i == 1 || i == 3 || i == 10)
1448 sprintf(buffer, fmt[i], minor);
1449
1450 /* 2 ==scsi/disc, 4 == scsi/part */
1451 if (i == 2 || i == 4)
1452 compat_name = write_old_sd_name(buffer, major, minor, ((i == 2) ? "" : (ptr + 4)));
1453
1454 /* 5 == scsi/mt */
1455 if (i == 5) {
1456 mode = ptr[2];
1457 if (mode == 'n')
1458 mode = '\0';
1459 sprintf(buffer, fmt[i], minor & 0x1f, mode);
1460 if (devname[namelen - 1] != 'n')
1461 ++compat_name;
1462 }
1463 /* 6 == ide/host/disc, 7 == ide/host/cd, 8 == ide/host/part */
1464 if (i == 6 || i == 7 || i == 8)
1465 /* last arg should be ignored for i == 6 or i== 7 */
1466 sprintf(buffer, fmt[i] , get_old_ide_name(major, minor), ptr + 4);
1467
1468 /* 9 == ide/host/mt */
1469 if (i == 9)
1470 sprintf(buffer, fmt[i], ptr + 2, minor & 0x7f);
1471
1472 /* 11 == vcc/ */
1473 if (i == 11) {
1474 sprintf(buffer, fmt[i], devname + 4);
1475 if (buffer[3] == '0')
1476 buffer[3] = '\0';
1477 }
1478 /* 12 == pty/ */
1479 if (i == 12) {
1480 pty1 = "pqrstuvwxyzabcde";
1481 pty2 = "0123456789abcdef";
1482 indexx = atoi(devname + 5);
1483 sprintf(buffer, fmt[i], (devname[4] == 'm') ? 'p' : 't', pty1[indexx >> 4], pty2[indexx & 0x0f]);
1484 }
1485 return compat_name;
1486} /* End Function get_old_name */
1487
1488static char get_old_ide_name(unsigned int major, unsigned int minor)
1489/* [SUMMARY] Get the old IDE name for a device.
1490 <major> The major number for the device.
1491 <minor> The minor number for the device.
1492 [RETURNS] The drive letter.
1493*/
1494{
1495 char letter = 'y'; /* 121 */
1496 char c = 'a'; /* 97 */
1497 int i = IDE0_MAJOR;
1498
1499 /* I hope it works like the previous code as it saves a few bytes. Tito ;P */
1500 do {
1501 if (i == IDE0_MAJOR || i == IDE1_MAJOR || i == IDE2_MAJOR
1502 || i == IDE3_MAJOR || i == IDE4_MAJOR || i == IDE5_MAJOR
1503 || i == IDE6_MAJOR || i == IDE7_MAJOR || i == IDE8_MAJOR
1504 || i == IDE9_MAJOR
1505 ) {
1506 if ((unsigned int)i == major) {
1507 letter = c;
1508 break;
1509 }
1510 c += 2;
1511 }
1512 i++;
1513 } while (i <= IDE9_MAJOR);
1514
1515 if (minor > 63)
1516 ++letter;
1517 return letter;
1518} /* End Function get_old_ide_name */
1519
1520static char *write_old_sd_name(char *buffer,
1521 unsigned int major, unsigned int minor,
1522 const char *part)
1523/* [SUMMARY] Write the old SCSI disc name to a buffer.
1524 <buffer> The buffer to write to.
1525 <major> The major number for the device.
1526 <minor> The minor number for the device.
1527 <part> The partition string. Must be "" for a whole-disc entry.
1528 [RETURNS] A pointer to the buffer on success, else NULL.
1529*/
1530{
1531 unsigned int disc_index;
1532
1533 if (major == 8) {
1534 sprintf(buffer, "sd%c%s", 'a' + (minor >> 4), part);
1535 return buffer;
1536 }
1537 if ((major > 64) && (major < 72)) {
1538 disc_index = ((major - 64) << 4) +(minor >> 4);
1539 if (disc_index < 26)
1540 sprintf(buffer, "sd%c%s", 'a' + disc_index, part);
1541 else
1542 sprintf(buffer, "sd%c%c%s", 'a' +(disc_index / 26) - 1, 'a' + disc_index % 26, part);
1543 return buffer;
1544 }
1545 return NULL;
1546} /* End Function write_old_sd_name */
1547
1548
1549/* expression.c */
1550
1551/*EXPERIMENTAL_FUNCTION*/
1552
1553int st_expr_expand(char *output, unsigned int length, const char *input,
1554 const char *(*get_variable_func)(const char *variable,
1555 void *info),
1556 void *info)
1557/* [SUMMARY] Expand an expression using Borne Shell-like unquoted rules.
1558 <output> The output expanded expression is written here.
1559 <length> The size of the output buffer.
1560 <input> The input expression. This may equal <<output>>.
1561 <get_variable> A function which will be used to get variable values. If
1562 this returns NULL, the environment is searched instead. If this is NULL,
1563 only the environment is searched.
1564 <info> An arbitrary pointer passed to <<get_variable>>.
1565 [RETURNS] TRUE on success, else FALSE.
1566*/
1567{
1568 char ch;
1569 unsigned int len;
1570 unsigned int out_pos = 0;
1571 const char *env;
1572 const char *ptr;
1573 struct passwd *pwent;
1574 char buffer[BUFFER_SIZE], tmp[STRING_LENGTH];
1575
1576 if (length > BUFFER_SIZE)
1577 length = BUFFER_SIZE;
1578 for (; TRUE; ++input) {
1579 switch (ch = *input) {
1580 case '$':
1581 /* Variable expansion */
1582 input = expand_variable(buffer, length, &out_pos, ++input, get_variable_func, info);
1583 if (input == NULL)
1584 return FALSE;
1585 break;
1586 case '~':
1587 /* Home directory expansion */
1588 ch = input[1];
1589 if (isspace(ch) ||(ch == '/') ||(ch == '\0')) {
1590 /* User's own home directory: leave separator for next time */
1591 env = getenv("HOME");
1592 if (env == NULL) {
1593 info_logger(LOG_INFO, bb_msg_variable_not_found, "HOME");
1594 return FALSE;
1595 }
1596 len = strlen(env);
1597 if (len + out_pos >= length)
1598 goto st_expr_expand_out;
1599 memcpy(buffer + out_pos, env, len + 1);
1600 out_pos += len;
1601 continue;
1602 }
1603 /* Someone else's home directory */
1604 for (ptr = ++input; !isspace(ch) && (ch != '/') && (ch != '\0'); ch = *++ptr)
1605 /* VOID */;
1606 len = ptr - input;
1607 if (len >= sizeof tmp)
1608 goto st_expr_expand_out;
1609 safe_memcpy(tmp, input, len);
1610 input = ptr - 1;
1611 pwent = getpwnam(tmp);
1612 if (pwent == NULL) {
1613 info_logger(LOG_INFO, "no pwent for: %s", tmp);
1614 return FALSE;
1615 }
1616 len = strlen(pwent->pw_dir);
1617 if (len + out_pos >= length)
1618 goto st_expr_expand_out;
1619 memcpy(buffer + out_pos, pwent->pw_dir, len + 1);
1620 out_pos += len;
1621 break;
1622 case '\0':
1623 /* Falltrough */
1624 default:
1625 if (out_pos >= length)
1626 goto st_expr_expand_out;
1627 buffer[out_pos++] = ch;
1628 if (ch == '\0') {
1629 memcpy(output, buffer, out_pos);
1630 return TRUE;
1631 }
1632 break;
1633 /* esac */
1634 }
1635 }
1636 return FALSE;
1637st_expr_expand_out:
1638 info_logger(LOG_INFO, bb_msg_small_buffer);
1639 return FALSE;
1640} /* End Function st_expr_expand */
1641
1642
1643/* Private functions follow */
1644
1645static const char *expand_variable(char *buffer, unsigned int length,
1646 unsigned int *out_pos, const char *input,
1647 const char *(*func)(const char *variable,
1648 void *info),
1649 void *info)
1650/* [SUMMARY] Expand a variable.
1651 <buffer> The buffer to write to.
1652 <length> The length of the output buffer.
1653 <out_pos> The current output position. This is updated.
1654 <input> A pointer to the input character pointer.
1655 <func> A function which will be used to get variable values. If this
1656 returns NULL, the environment is searched instead. If this is NULL, only
1657 the environment is searched.
1658 <info> An arbitrary pointer passed to <<func>>.
1659 <errfp> Diagnostic messages are written here.
1660 [RETURNS] A pointer to the end of this subexpression on success, else NULL.
1661*/
1662{
1663 char ch;
1664 int len;
1665 unsigned int open_braces;
1666 const char *env, *ptr;
1667 char tmp[STRING_LENGTH];
1668
1669 ch = input[0];
1670 if (ch == '$') {
1671 /* Special case for "$$": PID */
1672 sprintf(tmp, "%d", (int) getpid());
1673 len = strlen(tmp);
1674 if (len + *out_pos >= length)
1675 goto expand_variable_out;
1676
1677 memcpy(buffer + *out_pos, tmp, len + 1);
1678 out_pos += len;
1679 return input;
1680 }
1681 /* Ordinary variable expansion, possibly in braces */
1682 if (ch != '{') {
1683 /* Simple variable expansion */
1684 for (ptr = input; isalnum(ch) || (ch == '_') || (ch == ':'); ch = *++ptr)
1685 /* VOID */;
1686 len = ptr - input;
1687 if ((size_t)len >= sizeof tmp)
1688 goto expand_variable_out;
1689
1690 safe_memcpy(tmp, input, len);
1691 input = ptr - 1;
1692 env = get_variable_v2(tmp, func, info);
1693 if (env == NULL) {
1694 info_logger(LOG_INFO, bb_msg_variable_not_found, tmp);
1695 return NULL;
1696 }
1697 len = strlen(env);
1698 if (len + *out_pos >= length)
1699 goto expand_variable_out;
1700
1701 memcpy(buffer + *out_pos, env, len + 1);
1702 *out_pos += len;
1703 return input;
1704 }
1705 /* Variable in braces: check for ':' tricks */
1706 ch = *++input;
1707 for (ptr = input; isalnum(ch) || (ch == '_'); ch = *++ptr)
1708 /* VOID */;
1709 if (ch == '}') {
1710 /* Must be simple variable expansion with "${var}" */
1711 len = ptr - input;
1712 if ((size_t)len >= sizeof tmp)
1713 goto expand_variable_out;
1714
1715 safe_memcpy(tmp, input, len);
1716 ptr = expand_variable(buffer, length, out_pos, tmp, func, info);
1717 if (ptr == NULL)
1718 return NULL;
1719 return input + len;
1720 }
1721 if (ch != ':' || ptr[1] != '-') {
1722 info_logger(LOG_INFO, "illegal char in var name");
1723 return NULL;
1724 }
1725 /* It's that handy "${var:-word}" expression. Check if var is defined */
1726 len = ptr - input;
1727 if ((size_t)len >= sizeof tmp)
1728 goto expand_variable_out;
1729
1730 safe_memcpy(tmp, input, len);
1731 /* Move input pointer to ':' */
1732 input = ptr;
1733 /* First skip to closing brace, taking note of nested expressions */
1734 ptr += 2;
1735 ch = ptr[0];
1736 for (open_braces = 1; open_braces > 0; ch = *++ptr) {
1737 switch (ch) {
1738 case '{':
1739 ++open_braces;
1740 break;
1741 case '}':
1742 --open_braces;
1743 break;
1744 case '\0':
1745 info_logger(LOG_INFO, "\"}\" not found in: %s", input);
1746 return NULL;
1747 default:
1748 break;
1749 }
1750 }
1751 --ptr;
1752 /* At this point ptr should point to closing brace of "${var:-word}" */
1753 env = get_variable_v2(tmp, func, info);
1754 if (env != NULL) {
1755 /* Found environment variable, so skip the input to the closing brace
1756 and return the variable */
1757 input = ptr;
1758 len = strlen(env);
1759 if (len + *out_pos >= length)
1760 goto expand_variable_out;
1761
1762 memcpy(buffer + *out_pos, env, len + 1);
1763 *out_pos += len;
1764 return input;
1765 }
1766 /* Environment variable was not found, so process word. Advance input
1767 pointer to start of word in "${var:-word}" */
1768 input += 2;
1769 len = ptr - input;
1770 if ((size_t)len >= sizeof tmp)
1771 goto expand_variable_out;
1772
1773 safe_memcpy(tmp, input, len);
1774 input = ptr;
1775 if (!st_expr_expand(tmp, STRING_LENGTH, tmp, func, info))
1776 return NULL;
1777 len = strlen(tmp);
1778 if (len + *out_pos >= length)
1779 goto expand_variable_out;
1780
1781 memcpy(buffer + *out_pos, tmp, len + 1);
1782 *out_pos += len;
1783 return input;
1784expand_variable_out:
1785 info_logger(LOG_INFO, bb_msg_small_buffer);
1786 return NULL;
1787} /* End Function expand_variable */
1788
1789
1790static const char *get_variable_v2(const char *variable,
1791 const char *(*func)(const char *variable, void *info),
1792 void *info)
1793/* [SUMMARY] Get a variable from the environment or .
1794 <variable> The variable name.
1795 <func> A function which will be used to get the variable. If this returns
1796 NULL, the environment is searched instead. If this is NULL, only the
1797 environment is searched.
1798 [RETURNS] The value of the variable on success, else NULL.
1799*/
1800{
1801 const char *value;
1802
1803 if (func != NULL) {
1804 value = (*func)(variable, info);
1805 if (value != NULL)
1806 return value;
1807 }
1808 return getenv(variable);
1809} /* End Function get_variable */
1810
1811/* END OF CODE */
1812
generated by cgit at 2024-05-15 15:42:00 (GMT)