1 /* blkid.c - Prints type, label and UUID of filesystem(s).
2 *
3 * Copyright 2013 Brad Conroy <bconroy@uis.edu>
4 *
5 * See ftp://ftp.kernel.org/pub/linux/utils/util-linux/v2.24/libblkid-docs/api-index-full.html
6
7 USE_BLKID(NEWTOY(blkid, "<1", TOYFLAG_BIN))
8 USE_FSTYPE(NEWTOY(fstype, "<1", TOYFLAG_BIN))
9
10 config BLKID
11 bool "blkid"
12 default y
13 help
14 usage: blkid DEV...
15
16 Prints type, label and UUID of filesystem on a block device or image.
17
18 config FSTYPE
19 bool "fstype"
20 default y
21 help
22 usage: fstype DEV...
23
24 Prints type of filesystem on a block device or image.
25 */
26
27 #define FOR_blkid
28 #include "toys.h"
29
30 struct fstype {
31 char *name;
32 uint64_t magic;
33 int magic_len, magic_offset, uuid_off, label_len, label_off;
34 };
35
36 static const struct fstype fstypes[] = {
37 {"ext2", 0xEF53, 2, 1080, 1128, 16, 1144}, // keep this first for ext3/4 check
38 // NTFS label actually 8/16 0x4d80 but horrible: 16 bit wide characters via
39 // codepage, something called a uuid that's only 8 bytes long...
40 {"ntfs", 0x5346544e, 4, 3, 0x48+(8<<24), 0, 0},
41
42 {"adfs", 0xadf5, 2, 0xc00, 0,0,0},
43 {"bfs", 0x1badface, 4, 0, 0,0,0},
44 {"btrfs", 0x4D5F53665248425FULL, 8, 65600, 65803, 256, 65819},
45 {"cramfs", 0x28cd3d45, 4, 0, 0, 16, 48},
46 {"f2fs", 0xF2F52010, 4, 1024, 1132, 16, 1110},
47 {"jfs", 0x3153464a, 4, 32768, 32920, 16, 32904},
48 {"nilfs", 0x3434, 2, 1030, 1176, 80, 1192},
49 {"reiserfs", 0x724573496552ULL, 6, 8244, 8276, 16, 8292},
50 {"reiserfs", 0x724573496552ULL, 6, 65588, 65620, 16, 65536},
51 {"romfs", 0x2d6d6f72, 4, 0, 0,0,0},
52 {"squashfs", 0x73717368, 4, 0, 0,0,0},
53 {"xiafs", 0x012fd16d, 4, 572, 0,0,0},
54 {"xfs", 0x42534658, 4, 0, 32, 12, 108},
55 {"vfat", 0x3233544146ULL, 5, 82, 67+(4<<24), 11, 71}, // fat32
56 {"vfat", 0x31544146, 4, 54, 39+(4<<24), 11, 43} // fat1
57 };
58
59 /* TODO if no args use proc/partitions */
do_blkid(int fd,char * name)60 void do_blkid(int fd, char *name)
61 {
62 int off, i, j;
63 char *type;
64
65 off = i = 0;
66
67 for (;;) {
68 int pass = 0, len;
69
70 // Read next block of data
71 len = readall(fd, toybuf, sizeof(toybuf));
72 if (len != sizeof(toybuf)) return;
73
74 // Iterate through types in range
75 for (i=0; i < sizeof(fstypes)/sizeof(struct fstype); i++) {
76 uint64_t test;
77
78 // Skip tests not in this 4k block
79 if (fstypes[i].magic_offset > off+sizeof(toybuf)) {
80 pass++;
81 continue;
82 }
83 if (fstypes[i].magic_offset < off) continue;
84
85 // Populate 64 bit little endian magic value
86 test = 0;
87 for (j = 0; j < fstypes[i].magic_len; j++)
88 test += ((uint64_t)toybuf[j+fstypes[i].magic_offset-off])<<(8*j);
89 if (test == fstypes[i].magic) break;
90 }
91
92 if (i == sizeof(fstypes)/sizeof(struct fstype)) {
93 off += len;
94 if (pass) continue;
95 return;
96 }
97 break;
98 }
99
100 // distinguish ext2/3/4
101 type = fstypes[i].name;
102 if (!i) {
103 if (toybuf[1116]&4) type = "ext3";
104 if (toybuf[1120]&64) type = "ext4";
105 }
106
107 // Could special case NTFS here...
108
109 // Output for fstype
110 if (*toys.which->name == 'f') {
111 puts(type);
112 return;
113 }
114
115 // output for blkid
116 printf("%s:",name);
117
118 if (fstypes[i].label_len)
119 printf(" LABEL=\"%.*s\"", fstypes[i].label_len,
120 toybuf+fstypes[i].label_off-off);
121
122 if (fstypes[i].uuid_off) {
123 int bits = 0x550, size = fstypes[i].uuid_off >> 24,
124 uoff = (fstypes[i].uuid_off & ((1<<24)-1))-off;
125
126 if (size) bits = 4*(size == 4);
127 else size = 16;
128
129 printf(" UUID=\"");
130 for (j = 0; j < size; j++) printf("-%02x"+!(bits & (1<<j)), toybuf[uoff+j]);
131 printf("\"");
132 }
133
134 printf(" TYPE=\"%s\"\n", type);
135 }
136
blkid_main(void)137 void blkid_main(void)
138 {
139 loopfiles(toys.optargs, do_blkid);
140 }
141
fstype_main(void)142 void fstype_main(void)
143 {
144 blkid_main();
145 }
146