xref: /NextBSD/sys/boot/efi/loader/devicename.c (revision ea41b2069698db5cfd8b1d3888556269b4fdc668)
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 __FBSDID("$FreeBSD$");
30 
31 #include <stand.h>
32 #include <string.h>
33 #include <sys/disklabel.h>
34 #include "bootstrap.h"
35 
36 #include <efi.h>
37 #include <efilib.h>
38 
39 static int efi_parsedev(struct devdesc **, const char *, const char **);
40 
41 /*
42  * Point (dev) at an allocated device specifier for the device matching the
43  * path in (devspec). If it contains an explicit device specification,
44  * use that.  If not, use the default device.
45  */
46 int
efi_getdev(void ** vdev,const char * devspec,const char ** path)47 efi_getdev(void **vdev, const char *devspec, const char **path)
48 {
49 	struct devdesc **dev = (struct devdesc **)vdev;
50 	int rv;
51 
52 	/*
53 	 * If it looks like this is just a path and no device, then
54 	 * use the current device instead.
55 	 */
56 	if (devspec == NULL || *devspec == '/' || !strchr(devspec, ':')) {
57 		rv = efi_parsedev(dev, getenv("currdev"), NULL);
58 		if (rv == 0 && path != NULL)
59 			*path = devspec;
60 		return (rv);
61 	}
62 
63 	/* Parse the device name off the beginning of the devspec. */
64 	return (efi_parsedev(dev, devspec, path));
65 }
66 
67 /*
68  * Point (dev) at an allocated device specifier matching the string version
69  * at the beginning of (devspec).  Return a pointer to the remaining
70  * text in (path).
71  *
72  * In all cases, the beginning of (devspec) is compared to the names
73  * of known devices in the device switch, and then any following text
74  * is parsed according to the rules applied to the device type.
75  *
76  * For disk-type devices, the syntax is:
77  *
78  * fs<unit>:
79  */
80 static int
efi_parsedev(struct devdesc ** dev,const char * devspec,const char ** path)81 efi_parsedev(struct devdesc **dev, const char *devspec, const char **path)
82 {
83 	struct devdesc *idev;
84 	struct devsw *dv;
85 	char *cp;
86 	const char *np;
87 	int i, err;
88 
89 	/* minimum length check */
90 	if (strlen(devspec) < 2)
91 		return (EINVAL);
92 
93 	/* look for a device that matches */
94 	for (i = 0; devsw[i] != NULL; i++) {
95 		dv = devsw[i];
96 		if (!strncmp(devspec, dv->dv_name, strlen(dv->dv_name)))
97 			break;
98 	}
99 	if (devsw[i] == NULL)
100 		return (ENOENT);
101 
102 	idev = malloc(sizeof(struct devdesc));
103 	if (idev == NULL)
104 		return (ENOMEM);
105 
106 	idev->d_dev = dv;
107 	idev->d_type = dv->dv_type;
108 	idev->d_unit = -1;
109 
110 	err = 0;
111 	np = devspec + strlen(dv->dv_name);
112 	if (*np != '\0' && *np != ':') {
113 		idev->d_unit = strtol(np, &cp, 0);
114 		if (cp == np) {
115 			idev->d_unit = -1;
116 			free(idev);
117 			return (EUNIT);
118 		}
119 	}
120 	if (*cp != '\0' && *cp != ':') {
121 		free(idev);
122 		return (EINVAL);
123 	}
124 
125 	if (path != NULL)
126 		*path = (*cp == 0) ? cp : cp + 1;
127 	if (dev != NULL)
128 		*dev = idev;
129 	else
130 		free(idev);
131 	return (0);
132 }
133 
134 char *
efi_fmtdev(void * vdev)135 efi_fmtdev(void *vdev)
136 {
137 	struct devdesc *dev = (struct devdesc *)vdev;
138 	static char buf[32];	/* XXX device length constant? */
139 
140 	switch(dev->d_type) {
141 	case DEVT_NONE:
142 		strcpy(buf, "(no device)");
143 		break;
144 
145 	default:
146 		sprintf(buf, "%s%d:", dev->d_dev->dv_name, dev->d_unit);
147 		break;
148 	}
149 
150 	return (buf);
151 }
152 
153 /*
154  * Set currdev to suit the value being supplied in (value)
155  */
156 int
efi_setcurrdev(struct env_var * ev,int flags,const void * value)157 efi_setcurrdev(struct env_var *ev, int flags, const void *value)
158 {
159 	struct devdesc *ncurr;
160 	int rv;
161 
162 	rv = efi_parsedev(&ncurr, value, NULL);
163 	if (rv != 0)
164 		return (rv);
165 
166 	free(ncurr);
167 	env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
168 	return (0);
169 }
170