xref: /freebsd/sys/geom/label/g_label_gpt.c (revision d7d962ead0b6e5e8a39202d0590022082bf5bfb6)
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 /* XXX: Also defined in geom/part/g_part_gpt.c */
48 struct g_part_gpt_entry {
49 	struct g_part_entry     base;
50 	struct gpt_ent          ent;
51 };
52 
53 /* XXX: Shamelessly stolen from g_part_gpt.c */
54 static void
55 sbuf_nprintf_utf16(struct sbuf *sb, uint16_t *str, size_t len)
56 {
57 	u_int bo;
58 	uint32_t ch;
59 	uint16_t c;
60 
61 	bo = LITTLE_ENDIAN;	/* GPT is little-endian */
62 	while (len > 0 && *str != 0) {
63 		ch = (bo == BIG_ENDIAN) ? be16toh(*str) : le16toh(*str);
64 		str++, len--;
65 		if ((ch & 0xf800) == 0xd800) {
66 			if (len > 0) {
67 				c = (bo == BIG_ENDIAN) ? be16toh(*str)
68 				    : le16toh(*str);
69 				str++, len--;
70 			} else
71 				c = 0xfffd;
72 			if ((ch & 0x400) == 0 && (c & 0xfc00) == 0xdc00) {
73 				ch = ((ch & 0x3ff) << 10) + (c & 0x3ff);
74 				ch += 0x10000;
75 			} else
76 				ch = 0xfffd;
77 		} else if (ch == 0xfffe) { /* BOM (U+FEFF) swapped. */
78 			bo = (bo == BIG_ENDIAN) ? LITTLE_ENDIAN : BIG_ENDIAN;
79 			continue;
80 		} else if (ch == 0xfeff) /* BOM (U+FEFF) unswapped. */
81 			continue;
82 
83 		/* Write the Unicode character in UTF-8 */
84 		if (ch < 0x80)
85 			sbuf_printf(sb, "%c", ch);
86 		else if (ch < 0x800)
87 			sbuf_printf(sb, "%c%c", 0xc0 | (ch >> 6),
88 			    0x80 | (ch & 0x3f));
89 		else if (ch < 0x10000)
90 			sbuf_printf(sb, "%c%c%c", 0xe0 | (ch >> 12),
91 			    0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
92 		else if (ch < 0x200000)
93 			sbuf_printf(sb, "%c%c%c%c", 0xf0 | (ch >> 18),
94 			    0x80 | ((ch >> 12) & 0x3f),
95 			    0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f));
96 	}
97 }
98 
99 static void
100 g_label_gpt_taste(struct g_consumer *cp, char *label, size_t size)
101 {
102 	struct g_provider *pp;
103 	struct g_part_table *tp;
104 	struct g_part_gpt_entry *part_gpt_entry;
105 	struct sbuf *lbl;
106 
107 	g_topology_assert_not();
108 	pp = cp->provider;
109 	tp = (struct g_part_table *)pp->geom->softc;
110 	label[0] = '\0';
111 
112 	/* We taste only partitions handled by GPART */
113 	if (strncmp(pp->geom->class->name, PART_CLASS_NAME, sizeof(PART_CLASS_NAME)))
114 		return;
115 	/* and only GPT */
116 	if (strncmp(tp->gpt_scheme->name, SCHEME_NAME, sizeof(SCHEME_NAME)))
117 		return;
118 
119 	part_gpt_entry = (struct g_part_gpt_entry *)pp->private;
120 
121 	/*
122 	 * Create sbuf with biggest possible size.
123 	 * We need max. 4 bytes for every 2-byte utf16 char.
124 	 */
125 	lbl = sbuf_new(NULL, NULL, sizeof(part_gpt_entry->ent.ent_name) << 1, SBUF_FIXEDLEN);
126 	/* Size is the number of characters, not bytes */
127 	sbuf_nprintf_utf16(lbl, part_gpt_entry->ent.ent_name, sizeof(part_gpt_entry->ent.ent_name) >> 1);
128 	sbuf_finish(lbl);
129 	strlcpy(label, sbuf_data(lbl), size);
130 	sbuf_delete(lbl);
131 }
132 
133 static void
134 g_label_gpt_uuid_taste(struct g_consumer *cp, char *label, size_t size)
135 {
136 	struct g_provider *pp;
137 	struct g_part_table *tp;
138 	struct g_part_gpt_entry *part_gpt_entry;
139 
140 	g_topology_assert_not();
141 	pp = cp->provider;
142 	tp = (struct g_part_table *)pp->geom->softc;
143 	label[0] = '\0';
144 
145 	/* We taste only partitions handled by GPART */
146 	if (strncmp(pp->geom->class->name, PART_CLASS_NAME, sizeof(PART_CLASS_NAME)))
147 		return;
148 	/* and only GPT */
149 	if (strncmp(tp->gpt_scheme->name, SCHEME_NAME, sizeof(SCHEME_NAME)))
150 		return;
151 
152 	part_gpt_entry = (struct g_part_gpt_entry *)pp->private;
153 	snprintf_uuid(label, size, &part_gpt_entry->ent.ent_uuid);
154 }
155 
156 struct g_label_desc g_label_gpt = {
157 	.ld_taste = g_label_gpt_taste,
158 	.ld_dirprefix = "gpt/",
159 	.ld_enabled = 1
160 };
161 
162 struct g_label_desc g_label_gpt_uuid = {
163 	.ld_taste = g_label_gpt_uuid_taste,
164 	.ld_dirprefix = "gptid/",
165 	.ld_enabled = 1
166 };
167 
168 G_LABEL_INIT(gpt, g_label_gpt, "Create device nodes for GPT labels");
169 G_LABEL_INIT(gptid, g_label_gpt_uuid, "Create device nodes for GPT UUIDs");
170