xref: /illumos-gate/usr/src/boot/efi/libefi/devicename.c (revision 9b9d39d2a32ff806d2431dbcc50968ef1e6d46b2)
1 /*
2  * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3  * Copyright (c) 2006 Marcel Moolenaar
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 
30 #include <stand.h>
31 #include <string.h>
32 #include <sys/disklabel.h>
33 #include <sys/param.h>
34 #include <bootstrap.h>
35 #include <disk.h>
36 #include <libzfs.h>
37 
38 #include <efi.h>
39 #include <efilib.h>
40 
41 static int efi_parsedev(struct devdesc **, const char *, const char **);
42 
43 /*
44  * Point (dev) at an allocated device specifier for the device matching the
45  * path in (devspec). If it contains an explicit device specification,
46  * use that.  If not, use the default device.
47  */
48 int
49 efi_getdev(void **vdev, const char *devspec, const char **path)
50 {
51 	struct devdesc **dev = (struct devdesc **)vdev;
52 	int rv;
53 
54 	/*
55 	 * If it looks like this is just a path and no device, then
56 	 * use the current device instead.
57 	 */
58 	if (devspec == NULL || *devspec == '/' || !strchr(devspec, ':')) {
59 		rv = efi_parsedev(dev, getenv("currdev"), NULL);
60 		if (rv == 0 && path != NULL)
61 			*path = devspec;
62 		return (rv);
63 	}
64 
65 	/* Parse the device name off the beginning of the devspec. */
66 	return (efi_parsedev(dev, devspec, path));
67 }
68 
69 /*
70  * Point (dev) at an allocated device specifier matching the string version
71  * at the beginning of (devspec).  Return a pointer to the remaining
72  * text in (path).
73  *
74  * In all cases, the beginning of (devspec) is compared to the names
75  * of known devices in the device switch, and then any following text
76  * is parsed according to the rules applied to the device type.
77  *
78  * For disk-type devices, the syntax is:
79  *
80  * fs<unit>:
81  */
82 static int
83 efi_parsedev(struct devdesc **dev, const char *devspec, const char **path)
84 {
85 	struct devdesc *idev;
86 	struct devsw *dv;
87 	int i, unit, err;
88 	char *cp;
89 	const char *np;
90 
91 	/* minimum length check */
92 	if (strlen(devspec) < 2)
93 		return (EINVAL);
94 
95 	/* look for a device that matches */
96 	for (i = 0; devsw[i] != NULL; i++) {
97 		dv = devsw[i];
98 		if (strncmp(devspec, dv->dv_name, strlen(dv->dv_name)) == 0)
99 			break;
100 	}
101 	if (devsw[i] == NULL)
102 		return (ENOENT);
103 
104 	np = devspec + strlen(dv->dv_name);
105 	idev = NULL;
106 	err = 0;
107 
108 	switch (dv->dv_type) {
109 	case DEVT_NONE:
110 		break;
111 
112 	case DEVT_DISK:
113 		idev = malloc(sizeof (struct disk_devdesc));
114 		if (idev == NULL)
115 			return (ENOMEM);
116 
117 		err = disk_parsedev((struct disk_devdesc *)idev, np, path);
118 		if (err != 0)
119 			goto fail;
120 		break;
121 
122 	case DEVT_ZFS:
123 		idev = malloc(sizeof (struct zfs_devdesc));
124 		if (idev == NULL)
125 			return (ENOMEM);
126 
127 		err = zfs_parsedev((struct zfs_devdesc *)idev, np, path);
128 		if (err != 0)
129 			goto fail;
130 		break;
131 
132 	default:
133 		idev = malloc(sizeof (struct devdesc));
134 		if (idev == NULL)
135 			return (ENOMEM);
136 
137 		unit = 0;
138 		cp = (char *)np;
139 
140 		if (*np != '\0' && *np != ':') {
141 			/* get unit number if present */
142 			errno = 0;
143 			unit = strtol(np, &cp, 0);
144 			if (errno != 0 || cp == np) {
145 				err = EUNIT;
146 				goto fail;
147 			}
148 		}
149 		if (*cp != '\0' && *cp != ':') {
150 			err = EINVAL;
151 			goto fail;
152 		}
153 
154 		idev->d_unit = unit;
155 		if (path != NULL)
156 			*path = (*cp == '\0') ? cp : cp + 1;
157 		break;
158 	}
159 
160 	idev->d_dev = dv;
161 
162 	if (dev != NULL)
163 		*dev = idev;
164 	else
165 		free(idev);
166 	return (0);
167 
168 fail:
169 	free(idev);
170 	return (err);
171 }
172 
173 char *
174 efi_fmtdev(void *vdev)
175 {
176 	struct devdesc *dev = (struct devdesc *)vdev;
177 	static char buf[SPECNAMELEN + 1];
178 
179 	switch (dev->d_dev->dv_type) {
180 	case DEVT_NONE:
181 		strlcpy(buf, "(no device)", sizeof (buf));
182 		break;
183 
184 	case DEVT_DISK:
185 		return (disk_fmtdev(vdev));
186 
187 	case DEVT_ZFS:
188 		return (zfs_fmtdev(dev));
189 
190 	default:
191 		snprintf(buf, sizeof (buf), "%s%d:", dev->d_dev->dv_name,
192 		    dev->d_unit);
193 		break;
194 	}
195 
196 	return (buf);
197 }
198 
199 /*
200  * Set currdev to suit the value being supplied in (value)
201  */
202 int
203 efi_setcurrdev(struct env_var *ev, int flags, const void *value)
204 {
205 	struct devdesc *ncurr;
206 	int rv;
207 
208 	rv = efi_parsedev(&ncurr, value, NULL);
209 	if (rv != 0)
210 		return (rv);
211 
212 	free(ncurr);
213 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
214 	return (0);
215 }
216