1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #include <sys/stat.h>
28 #include <sys/types.h>
29 #include <fcntl.h>
30 #include <sys/openpromio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <stdio.h> /* sprintf() */
34 #include <unistd.h>
35
36 /*
37 * opp_zalloc(): allocates and initializes a struct openpromio
38 *
39 * input: size_t: the size of the variable-length part of the openpromio
40 * const char *: an initial value for oprom_array, if non-NULL
41 * output: struct openpromio: the allocated, initialized openpromio
42 */
43
44 static struct openpromio *
opp_zalloc(size_t size,const char * prop)45 opp_zalloc(size_t size, const char *prop)
46 {
47 struct openpromio *opp = malloc(sizeof (struct openpromio) + size);
48
49 if (opp != NULL) {
50 (void) memset(opp, 0, sizeof (struct openpromio) + size);
51 opp->oprom_size = size;
52 if (prop != NULL)
53 (void) strcpy(opp->oprom_array, prop);
54 }
55 return (opp);
56 }
57
58 /*
59 * goto_rootnode(): moves to the root of the devinfo tree
60 *
61 * input: int: an open descriptor to /dev/openprom
62 * output: int: nonzero on success
63 */
64
65 static int
goto_rootnode(int prom_fd)66 goto_rootnode(int prom_fd)
67 {
68 struct openpromio op = { sizeof (int), 0 };
69
70 /* zero it explicitly since a union is involved */
71 op.oprom_node = 0;
72 return (ioctl(prom_fd, OPROMNEXT, &op) == 0);
73 }
74
75 /*
76 * return_property(): returns the value of a given property
77 *
78 * input: int: an open descriptor to /dev/openprom
79 * const char *: the property to look for in the current devinfo node
80 * output: the value of that property (dynamically allocated)
81 */
82
83 static char *
return_property(int prom_fd,const char * prop)84 return_property(int prom_fd, const char *prop)
85 {
86 int proplen;
87 char *result;
88 struct openpromio *opp = opp_zalloc(strlen(prop) + 1, prop);
89
90 if (opp == NULL)
91 return (NULL);
92
93 if (ioctl(prom_fd, OPROMGETPROPLEN, opp) == -1) {
94 free(opp);
95 return (NULL);
96 }
97
98 proplen = opp->oprom_len;
99 if (proplen > (strlen(prop) + 1)) {
100 free(opp);
101 opp = opp_zalloc(proplen, prop);
102 if (opp == NULL)
103 return (NULL);
104 }
105
106 if (ioctl(prom_fd, OPROMGETPROP, opp) == -1) {
107 free(opp);
108 return (NULL);
109 }
110
111 result = strdup(opp->oprom_array);
112 free(opp);
113 return (result);
114 }
115
116 /*
117 * sanitize_class_id(): translates the class id into a canonical format,
118 * so that it can be used easily with dhcptab(5).
119 *
120 * input: char *: the class id to canonicalize
121 * output: void
122 */
123
124 static void
sanitize_class_id(char * src_ptr)125 sanitize_class_id(char *src_ptr)
126 {
127 char *dst_ptr = src_ptr;
128
129 /* remove all spaces and change all commas to periods */
130 while (*src_ptr != '\0') {
131
132 switch (*src_ptr) {
133
134 case ' ':
135 break;
136
137 case ',':
138 *dst_ptr++ = '.';
139 break;
140
141 default:
142 *dst_ptr++ = *src_ptr;
143 break;
144 }
145 src_ptr++;
146 }
147 *dst_ptr = '\0';
148 }
149
150 /*
151 * get_class_id(): retrieves the class id from the prom, then canonicalizes it
152 *
153 * input: void
154 * output: char *: the class id (dynamically allocated and sanitized)
155 */
156
157 char *
get_class_id(void)158 get_class_id(void)
159 {
160 int prom_fd;
161 char *name, *class_id = NULL;
162 size_t len;
163
164 prom_fd = open("/dev/openprom", O_RDONLY);
165 if (prom_fd == -1)
166 return (NULL);
167
168 if (goto_rootnode(prom_fd) == 0) {
169 (void) close(prom_fd);
170 return (NULL);
171 }
172
173 /*
174 * the `name' property is the same as the result of `uname -i', modulo
175 * some stylistic issues we fix up via sanitize_class_id() below.
176 */
177
178 name = return_property(prom_fd, "name");
179 (void) close(prom_fd);
180 if (name == NULL)
181 return (NULL);
182
183 /*
184 * if the name is not prefixed with a vendor name, add "SUNW," to make
185 * it more likely to be globally unique; see PSARC/2004/674.
186 */
187
188 if (strchr(name, ',') == NULL) {
189 len = strlen(name) + sizeof ("SUNW,");
190 class_id = malloc(len);
191 if (class_id == NULL) {
192 free(name);
193 return (NULL);
194 }
195 (void) snprintf(class_id, len, "SUNW,%s", name);
196 free(name);
197 } else {
198 class_id = name;
199 }
200
201 sanitize_class_id(class_id);
202 return (class_id);
203 }
204