xref: /freebsd/sys/geom/label/g_label_gpt.c (revision 63a938566d524836885917d95bd491aa4400b181)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2008 Marius Nuennerich
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/kobj.h>
37 #include <sys/gpt.h>
38 #include <sys/sbuf.h>
39 
40 #include <geom/geom.h>
41 #include <geom/label/g_label.h>
42 #include <geom/part/g_part.h>
43 
44 #define	PART_CLASS_NAME	"PART"
45 #define	SCHEME_NAME	"GPT"
46 
47 #define	G_LABEL_GPT_VOLUME_DIR	"gpt"
48 #define	G_LABEL_GPT_ID_DIR	"gptid"
49 
50 /* XXX: Also defined in geom/part/g_part_gpt.c */
51 struct g_part_gpt_entry {
52 	struct g_part_entry     base;
53 	struct gpt_ent          ent;
54 };
55 
56 /* XXX: Shamelessly stolen from g_part_gpt.c */
57 static void
58 sbuf_nprintf_utf16(struct sbuf *sb, uint16_t *str, size_t len)
59 {
60 	u_int bo;
61 	uint32_t ch;
62 	uint16_t c;
63 
64 	bo = LITTLE_ENDIAN;	/* GPT is little-endian */
65 	while (len > 0 && *str != 0) {
66 		ch = (bo == BIG_ENDIAN) ? be16toh(*str) : le16toh(*str);
67 		str++, len--;
68 		if ((ch & 0xf800) == 0xd800) {
69 			if (len > 0) {
70 				c = (bo == BIG_ENDIAN) ? be16toh(*str)
71 				    : le16toh(*str);
72 				str++, len--;
73 			} else
74 				c = 0xfffd;
75 			if ((ch & 0x400) == 0 && (c & 0xfc00) == 0xdc00) {
76 				ch = ((ch & 0x3ff) << 10) + (c & 0x3ff);
77 				ch += 0x10000;
78 			} else
79 				ch = 0xfffd;
80 		} else if (ch == 0xfffe) { /* BOM (U+FEFF) swapped. */
81 			bo = (bo == BIG_ENDIAN) ? LITTLE_ENDIAN : BIG_ENDIAN;
82 			continue;
83 		} else if (ch == 0xfeff) /* BOM (U+FEFF) unswapped. */
84 			continue;
85 
86 		/* Write the Unicode character in UTF-8 */
87 		if (ch < 0x80)
88 			sbuf_printf(sb, "%c", ch);
89 		else if (ch < 0x800)
90 			sbuf_printf(sb, "%c%c", 0xc0 | (ch >> 6),
91 			    0x80 | (ch & 0x3f));
92 		else if (ch < 0x10000)
93 			sbuf_printf(sb, "%c%c%c", 0xe0 | (ch >> 12),
94 			    0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
95 		else if (ch < 0x200000)
96 			sbuf_printf(sb, "%c%c%c%c", 0xf0 | (ch >> 18),
97 			    0x80 | ((ch >> 12) & 0x3f),
98 			    0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
99 	}
100 }
101 
102 static void
103 g_label_gpt_taste(struct g_consumer *cp, char *label, size_t size)
104 {
105 	struct g_provider *pp;
106 	struct g_part_table *tp;
107 	struct g_part_gpt_entry *part_gpt_entry;
108 	struct sbuf *lbl;
109 
110 	g_topology_assert_not();
111 	pp = cp->provider;
112 	tp = (struct g_part_table *)pp->geom->softc;
113 	label[0] = '\0';
114 
115 	/* We taste only partitions handled by GPART */
116 	if (strncmp(pp->geom->class->name, PART_CLASS_NAME, sizeof(PART_CLASS_NAME)))
117 		return;
118 	/* and only GPT */
119 	if (strncmp(tp->gpt_scheme->name, SCHEME_NAME, sizeof(SCHEME_NAME)))
120 		return;
121 
122 	part_gpt_entry = (struct g_part_gpt_entry *)pp->private;
123 
124 	/*
125 	 * Create sbuf with biggest possible size.
126 	 * We need max. 4 bytes for every 2-byte utf16 char.
127 	 */
128 	lbl = sbuf_new(NULL, NULL, sizeof(part_gpt_entry->ent.ent_name) << 1, SBUF_FIXEDLEN);
129 	/* Size is the number of characters, not bytes */
130 	sbuf_nprintf_utf16(lbl, part_gpt_entry->ent.ent_name, sizeof(part_gpt_entry->ent.ent_name) >> 1);
131 	sbuf_finish(lbl);
132 	strlcpy(label, sbuf_data(lbl), size);
133 	sbuf_delete(lbl);
134 }
135 
136 static void
137 g_label_gpt_uuid_taste(struct g_consumer *cp, char *label, size_t size)
138 {
139 	struct g_provider *pp;
140 	struct g_part_table *tp;
141 	struct g_part_gpt_entry *part_gpt_entry;
142 
143 	g_topology_assert_not();
144 	pp = cp->provider;
145 	tp = (struct g_part_table *)pp->geom->softc;
146 	label[0] = '\0';
147 
148 	/* We taste only partitions handled by GPART */
149 	if (strncmp(pp->geom->class->name, PART_CLASS_NAME, sizeof(PART_CLASS_NAME)))
150 		return;
151 	/* and only GPT */
152 	if (strncmp(tp->gpt_scheme->name, SCHEME_NAME, sizeof(SCHEME_NAME)))
153 		return;
154 
155 	part_gpt_entry = (struct g_part_gpt_entry *)pp->private;
156 	snprintf_uuid(label, size, &part_gpt_entry->ent.ent_uuid);
157 }
158 
159 struct g_label_desc g_label_gpt = {
160 	.ld_taste = g_label_gpt_taste,
161 	.ld_dir = G_LABEL_GPT_VOLUME_DIR,
162 	.ld_enabled = 1
163 };
164 
165 struct g_label_desc g_label_gpt_uuid = {
166 	.ld_taste = g_label_gpt_uuid_taste,
167 	.ld_dir = G_LABEL_GPT_ID_DIR,
168 	.ld_enabled = 1
169 };
170 
171 G_LABEL_INIT(gpt, g_label_gpt, "Create device nodes for GPT labels");
172 G_LABEL_INIT(gptid, g_label_gpt_uuid, "Create device nodes for GPT UUIDs");
173