xref: /freebsd/sys/geom/label/g_label_gpt.c (revision 6ae1554a5d9b318f8ad53ccc39fa5a961403da73)
1 /*-
2  * Copyright (c) 2008 Marius Nuennerich
3  * All rights reserved.
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  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/malloc.h>
34 #include <sys/kobj.h>
35 #include <sys/gpt.h>
36 #include <sys/sbuf.h>
37 
38 #include <geom/geom.h>
39 #include <geom/label/g_label.h>
40 #include <geom/part/g_part.h>
41 
42 #define	PART_CLASS_NAME	"PART"
43 #define	SCHEME_NAME	"GPT"
44 
45 #define	G_LABEL_GPT_VOLUME_DIR	"gpt"
46 #define	G_LABEL_GPT_ID_DIR	"gptid"
47 
48 /* XXX: Also defined in geom/part/g_part_gpt.c */
49 struct g_part_gpt_entry {
50 	struct g_part_entry     base;
51 	struct gpt_ent          ent;
52 };
53 
54 /* XXX: Shamelessly stolen from g_part_gpt.c */
55 static void
56 sbuf_nprintf_utf16(struct sbuf *sb, uint16_t *str, size_t len)
57 {
58 	u_int bo;
59 	uint32_t ch;
60 	uint16_t c;
61 
62 	bo = LITTLE_ENDIAN;	/* GPT is little-endian */
63 	while (len > 0 && *str != 0) {
64 		ch = (bo == BIG_ENDIAN) ? be16toh(*str) : le16toh(*str);
65 		str++, len--;
66 		if ((ch & 0xf800) == 0xd800) {
67 			if (len > 0) {
68 				c = (bo == BIG_ENDIAN) ? be16toh(*str)
69 				    : le16toh(*str);
70 				str++, len--;
71 			} else
72 				c = 0xfffd;
73 			if ((ch & 0x400) == 0 && (c & 0xfc00) == 0xdc00) {
74 				ch = ((ch & 0x3ff) << 10) + (c & 0x3ff);
75 				ch += 0x10000;
76 			} else
77 				ch = 0xfffd;
78 		} else if (ch == 0xfffe) { /* BOM (U+FEFF) swapped. */
79 			bo = (bo == BIG_ENDIAN) ? LITTLE_ENDIAN : BIG_ENDIAN;
80 			continue;
81 		} else if (ch == 0xfeff) /* BOM (U+FEFF) unswapped. */
82 			continue;
83 
84 		/* Write the Unicode character in UTF-8 */
85 		if (ch < 0x80)
86 			sbuf_printf(sb, "%c", ch);
87 		else if (ch < 0x800)
88 			sbuf_printf(sb, "%c%c", 0xc0 | (ch >> 6),
89 			    0x80 | (ch & 0x3f));
90 		else if (ch < 0x10000)
91 			sbuf_printf(sb, "%c%c%c", 0xe0 | (ch >> 12),
92 			    0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
93 		else if (ch < 0x200000)
94 			sbuf_printf(sb, "%c%c%c%c", 0xf0 | (ch >> 18),
95 			    0x80 | ((ch >> 12) & 0x3f),
96 			    0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
97 	}
98 }
99 
100 static void
101 g_label_gpt_taste(struct g_consumer *cp, char *label, size_t size)
102 {
103 	struct g_provider *pp;
104 	struct g_part_table *tp;
105 	struct g_part_gpt_entry *part_gpt_entry;
106 	struct sbuf *lbl;
107 
108 	g_topology_assert_not();
109 	pp = cp->provider;
110 	tp = (struct g_part_table *)pp->geom->softc;
111 	label[0] = '\0';
112 
113 	/* We taste only partitions handled by GPART */
114 	if (strncmp(pp->geom->class->name, PART_CLASS_NAME, sizeof(PART_CLASS_NAME)))
115 		return;
116 	/* and only GPT */
117 	if (strncmp(tp->gpt_scheme->name, SCHEME_NAME, sizeof(SCHEME_NAME)))
118 		return;
119 
120 	part_gpt_entry = (struct g_part_gpt_entry *)pp->private;
121 
122 	/*
123 	 * Create sbuf with biggest possible size.
124 	 * We need max. 4 bytes for every 2-byte utf16 char.
125 	 */
126 	lbl = sbuf_new(NULL, NULL, sizeof(part_gpt_entry->ent.ent_name) << 1, SBUF_FIXEDLEN);
127 	/* Size is the number of characters, not bytes */
128 	sbuf_nprintf_utf16(lbl, part_gpt_entry->ent.ent_name, sizeof(part_gpt_entry->ent.ent_name) >> 1);
129 	sbuf_finish(lbl);
130 	strlcpy(label, sbuf_data(lbl), size);
131 	sbuf_delete(lbl);
132 }
133 
134 static void
135 g_label_gpt_uuid_taste(struct g_consumer *cp, char *label, size_t size)
136 {
137 	struct g_provider *pp;
138 	struct g_part_table *tp;
139 	struct g_part_gpt_entry *part_gpt_entry;
140 
141 	g_topology_assert_not();
142 	pp = cp->provider;
143 	tp = (struct g_part_table *)pp->geom->softc;
144 	label[0] = '\0';
145 
146 	/* We taste only partitions handled by GPART */
147 	if (strncmp(pp->geom->class->name, PART_CLASS_NAME, sizeof(PART_CLASS_NAME)))
148 		return;
149 	/* and only GPT */
150 	if (strncmp(tp->gpt_scheme->name, SCHEME_NAME, sizeof(SCHEME_NAME)))
151 		return;
152 
153 	part_gpt_entry = (struct g_part_gpt_entry *)pp->private;
154 	snprintf_uuid(label, size, &part_gpt_entry->ent.ent_uuid);
155 }
156 
157 struct g_label_desc g_label_gpt = {
158 	.ld_taste = g_label_gpt_taste,
159 	.ld_dir = G_LABEL_GPT_VOLUME_DIR,
160 	.ld_enabled = 1
161 };
162 
163 struct g_label_desc g_label_gpt_uuid = {
164 	.ld_taste = g_label_gpt_uuid_taste,
165 	.ld_dir = G_LABEL_GPT_ID_DIR,
166 	.ld_enabled = 1
167 };
168 
169 G_LABEL_INIT(gpt, g_label_gpt, "Create device nodes for GPT labels");
170 G_LABEL_INIT(gptid, g_label_gpt_uuid, "Create device nodes for GPT UUIDs");
171