1 /* ubirename - port of the ubirename from the mtd-utils package
2  *
3  * A utility to rename one UBI volume.
4  *
5  * 2016-03-01 Sven Eisenberg <sven.eisenberg@novero.com>
6  *
7  * Licensed under GPLv2, see file LICENSE in this source tree.
8  */
9 //config:config UBIRENAME
10 //config:	bool "ubirename (2.4 kb)"
11 //config:	default y
12 //config:	help
13 //config:	Utility to rename UBI volumes
14 
15 //applet:IF_UBIRENAME(APPLET(ubirename, BB_DIR_USR_SBIN, BB_SUID_DROP))
16 /* not NOEXEC: if flash operation stalls, use less memory in "hung" process */
17 
18 //kbuild:lib-$(CONFIG_UBIRENAME) += ubirename.o
19 
20 //usage:#define ubirename_trivial_usage
21 //usage:	"UBI_DEVICE OLD_VOLNAME NEW_VOLNAME [OLD2 NEW2]..."
22 //usage:#define ubirename_full_usage "\n\n"
23 //usage:	"Rename UBI volumes on UBI_DEVICE"
24 
25 #include "libbb.h"
26 #include <mtd/mtd-user.h>
27 
28 #ifndef __packed
29 # define __packed __attribute__((packed))
30 #endif
31 
32 // from ubi-media.h
33 #define UBI_MAX_VOLUME_NAME 127
34 #define UBI_MAX_VOLUMES     128
35 // end ubi-media.h
36 
37 // from ubi-user.h
38 /* ioctl commands of UBI character devices */
39 #define UBI_IOC_MAGIC 'o'
40 
41 /* Re-name volumes */
42 #define UBI_IOCRNVOL _IOW(UBI_IOC_MAGIC, 3, struct ubi_rnvol_req)
43 
44 /* Maximum amount of UBI volumes that can be re-named at one go */
45 #define UBI_MAX_RNVOL 32
46 
47 struct ubi_rnvol_req {
48 	int32_t count;
49 	int8_t  padding1[12];
50 	struct {
51 		int32_t vol_id;
52 		int16_t name_len;
53 		int8_t  padding2[2];
54 		char    name[UBI_MAX_VOLUME_NAME + 1];
55 	} ents[UBI_MAX_RNVOL];
56 } __packed;
57 // end ubi-user.h
58 
59 int ubirename_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
ubirename_main(int argc,char ** argv)60 int ubirename_main(int argc, char **argv)
61 {
62 	struct ubi_rnvol_req *rnvol;
63 	const char *ubi_devname;
64 	unsigned ubi_devnum;
65 	unsigned n;
66 
67 	/* argc can be 4, 6, 8, ... */
68 	if ((argc & 1) || (argc >>= 1) < 2)
69 		bb_show_usage();
70 
71 	rnvol = xzalloc(sizeof(*rnvol));
72 	rnvol->count = --argc;
73 	if (argc > ARRAY_SIZE(rnvol->ents))
74 		bb_simple_error_msg_and_die("too many renames requested");
75 
76 	ubi_devname = argv[1];
77 	ubi_devnum = ubi_devnum_from_devname(ubi_devname);
78 
79 	n = 0;
80 	argv += 2;
81 	while (argv[0]) {
82 		rnvol->ents[n].vol_id = ubi_get_volid_by_name(ubi_devnum, argv[0]);
83 
84 		/* strnlen avoids overflow of 16-bit field (paranoia) */
85 		rnvol->ents[n].name_len = strnlen(argv[1], sizeof(rnvol->ents[n].name));
86 		if (rnvol->ents[n].name_len >= sizeof(rnvol->ents[n].name))
87 			bb_error_msg_and_die("new name '%s' is too long", argv[1]);
88 
89 		strcpy(rnvol->ents[n].name, argv[1]);
90 		n++;
91 		argv += 2;
92 	}
93 
94 	xioctl(xopen(ubi_devname, O_RDONLY), UBI_IOCRNVOL, rnvol);
95 
96 	return 0;
97 }
98