xref: /freebsd/sys/geom/label/g_label_gpt.c (revision b76ef9a7cb8a7c62d10ae8101f41014f34819174)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
32 #include <sys/malloc.h>
33 #include <sys/kobj.h>
34 #include <sys/gpt.h>
35 #include <sys/sbuf.h>
36 
37 #include <geom/geom.h>
38 #include <geom/label/g_label.h>
39 #include <geom/part/g_part.h>
40 
41 #define	PART_CLASS_NAME	"PART"
42 #define	SCHEME_NAME	"GPT"
43 
44 /* XXX: Also defined in geom/part/g_part_gpt.c */
45 struct g_part_gpt_entry {
46 	struct g_part_entry     base;
47 	struct gpt_ent          ent;
48 };
49 
50 /* XXX: Shamelessly stolen from g_part_gpt.c */
51 static void
52 sbuf_nprintf_utf16(struct sbuf *sb, uint16_t *str, size_t len)
53 {
54 	u_int bo;
55 	uint32_t ch;
56 	uint16_t c;
57 
58 	bo = LITTLE_ENDIAN;	/* GPT is little-endian */
59 	while (len > 0 && *str != 0) {
60 		ch = (bo == BIG_ENDIAN) ? be16toh(*str) : le16toh(*str);
61 		str++, len--;
62 		if ((ch & 0xf800) == 0xd800) {
63 			if (len > 0) {
64 				c = (bo == BIG_ENDIAN) ? be16toh(*str)
65 				    : le16toh(*str);
66 				str++, len--;
67 			} else
68 				c = 0xfffd;
69 			if ((ch & 0x400) == 0 && (c & 0xfc00) == 0xdc00) {
70 				ch = ((ch & 0x3ff) << 10) + (c & 0x3ff);
71 				ch += 0x10000;
72 			} else
73 				ch = 0xfffd;
74 		} else if (ch == 0xfffe) { /* BOM (U+FEFF) swapped. */
75 			bo = (bo == BIG_ENDIAN) ? LITTLE_ENDIAN : BIG_ENDIAN;
76 			continue;
77 		} else if (ch == 0xfeff) /* BOM (U+FEFF) unswapped. */
78 			continue;
79 
80 		/* Write the Unicode character in UTF-8 */
81 		if (ch < 0x80)
82 			sbuf_printf(sb, "%c", ch);
83 		else if (ch < 0x800)
84 			sbuf_printf(sb, "%c%c", 0xc0 | (ch >> 6),
85 			    0x80 | (ch & 0x3f));
86 		else if (ch < 0x10000)
87 			sbuf_printf(sb, "%c%c%c", 0xe0 | (ch >> 12),
88 			    0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
89 		else if (ch < 0x200000)
90 			sbuf_printf(sb, "%c%c%c%c", 0xf0 | (ch >> 18),
91 			    0x80 | ((ch >> 12) & 0x3f),
92 			    0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
93 	}
94 }
95 
96 static void
97 g_label_gpt_taste(struct g_consumer *cp, char *label, size_t size)
98 {
99 	struct g_provider *pp;
100 	struct g_part_table *tp;
101 	struct g_part_gpt_entry *part_gpt_entry;
102 	struct sbuf *lbl;
103 
104 	g_topology_assert_not();
105 	pp = cp->provider;
106 	tp = (struct g_part_table *)pp->geom->softc;
107 	label[0] = '\0';
108 
109 	/* We taste only partitions handled by GPART */
110 	if (strncmp(pp->geom->class->name, PART_CLASS_NAME, sizeof(PART_CLASS_NAME)))
111 		return;
112 	/* and only GPT */
113 	if (strncmp(tp->gpt_scheme->name, SCHEME_NAME, sizeof(SCHEME_NAME)))
114 		return;
115 
116 	part_gpt_entry = (struct g_part_gpt_entry *)pp->private;
117 
118 	/*
119 	 * Create sbuf with biggest possible size.
120 	 * We need max. 4 bytes for every 2-byte utf16 char.
121 	 */
122 	lbl = sbuf_new(NULL, NULL, sizeof(part_gpt_entry->ent.ent_name) << 1, SBUF_FIXEDLEN);
123 	/* Size is the number of characters, not bytes */
124 	sbuf_nprintf_utf16(lbl, part_gpt_entry->ent.ent_name, sizeof(part_gpt_entry->ent.ent_name) >> 1);
125 	sbuf_finish(lbl);
126 	strlcpy(label, sbuf_data(lbl), size);
127 	sbuf_delete(lbl);
128 }
129 
130 static void
131 g_label_gpt_uuid_taste(struct g_consumer *cp, char *label, size_t size)
132 {
133 	struct g_provider *pp;
134 	struct g_part_table *tp;
135 	struct g_part_gpt_entry *part_gpt_entry;
136 
137 	g_topology_assert_not();
138 	pp = cp->provider;
139 	tp = (struct g_part_table *)pp->geom->softc;
140 	label[0] = '\0';
141 
142 	/* We taste only partitions handled by GPART */
143 	if (strncmp(pp->geom->class->name, PART_CLASS_NAME, sizeof(PART_CLASS_NAME)))
144 		return;
145 	/* and only GPT */
146 	if (strncmp(tp->gpt_scheme->name, SCHEME_NAME, sizeof(SCHEME_NAME)))
147 		return;
148 
149 	part_gpt_entry = (struct g_part_gpt_entry *)pp->private;
150 	snprintf_uuid(label, size, &part_gpt_entry->ent.ent_uuid);
151 }
152 
153 struct g_label_desc g_label_gpt = {
154 	.ld_taste = g_label_gpt_taste,
155 	.ld_dirprefix = "gpt/",
156 	.ld_enabled = 1
157 };
158 
159 struct g_label_desc g_label_gpt_uuid = {
160 	.ld_taste = g_label_gpt_uuid_taste,
161 	.ld_dirprefix = "gptid/",
162 	.ld_enabled = 1
163 };
164 
165 G_LABEL_INIT(gpt, g_label_gpt, "Create device nodes for GPT labels");
166 G_LABEL_INIT(gptid, g_label_gpt_uuid, "Create device nodes for GPT UUIDs");
167