usr/src/boot/sys/boot/efi/loader/devicename.c

   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 #include "loader_efi.h"
  42
  43 static int efi_parsedev(struct devdesc **, const char *, const char **);
  44
  45 /*
  46  * Point (dev) at an allocated device specifier for the device matching the
  47  * path in (devspec). If it contains an explicit device specification,
  48  * use that.  If not, use the default device.
  49  */
  50 int
  51 efi_getdev(void **vdev, const char *devspec, const char **path)
  52 {
  53         struct devdesc **dev = (struct devdesc **)vdev;
  54         int rv;
  55
  56         /*
  57          * If it looks like this is just a path and no device, then
  58          * use the current device instead.
  59          */
  60         if (devspec == NULL || *devspec == '/' || !strchr(devspec, ':')) {
  61                 rv = efi_parsedev(dev, getenv("currdev"), NULL);
  62                 if (rv == 0 && path != NULL)
  63                         *path = devspec;
  64                 return (rv);
  65         }
  66
  67         /* Parse the device name off the beginning of the devspec. */
  68         return (efi_parsedev(dev, devspec, path));
  69 }
  70
  71 /*
  72  * Point (dev) at an allocated device specifier matching the string version
  73  * at the beginning of (devspec).  Return a pointer to the remaining
  74  * text in (path).
  75  *
  76  * In all cases, the beginning of (devspec) is compared to the names
  77  * of known devices in the device switch, and then any following text
  78  * is parsed according to the rules applied to the device type.
  79  *
  80  * For disk-type devices, the syntax is:
  81  *
  82  * fs<unit>:
  83  */
  84 static int
  85 efi_parsedev(struct devdesc **dev, const char *devspec, const char **path)
  86 {
  87         struct devdesc *idev;
  88         struct devsw *dv;
  89         int i, unit, err;
  90         char *cp;
  91         const char *np;
  92
  93         /* minimum length check */
  94         if (strlen(devspec) < 2)
  95                 return (EINVAL);
  96
  97         /* look for a device that matches */
  98         for (i = 0; devsw[i] != NULL; i++) {
  99                 dv = devsw[i];
 100                 if (strncmp(devspec, dv->dv_name, strlen(dv->dv_name)) == 0)
 101                         break;
 102         }
 103         if (devsw[i] == NULL)
 104                 return (ENOENT);
 105
 106         np = devspec + strlen(dv->dv_name);
 107         idev = NULL;
 108         err = 0;
 109
 110         switch (dv->dv_type) {
 111         case DEVT_NONE:
 112                 break;
 113
 114         case DEVT_DISK:
 115                 idev = malloc(sizeof (struct disk_devdesc));
 116                 if (idev == NULL)
 117                         return (ENOMEM);
 118
 119                 err = disk_parsedev((struct disk_devdesc *)idev, np, path);
 120                 if (err != 0)
 121                         goto fail;
 122                 break;
 123
 124         case DEVT_ZFS:
 125                 idev = malloc(sizeof (struct zfs_devdesc));
 126                 if (idev == NULL)
 127                         return (ENOMEM);
 128
 129                 err = zfs_parsedev((struct zfs_devdesc *)idev, np, path);
 130                 if (err != 0)
 131                         goto fail;
 132                 break;
 133
 134         default:
 135                 idev = malloc(sizeof (struct devdesc));
 136                 if (idev == NULL)
 137                         return (ENOMEM);
 138
 139                 unit = 0;
 140                 cp = (char *)np;
 141
 142                 if (*np != '\0' && *np != ':') {
 143                         /* get unit number if present */
 144                         errno = 0;
 145                         unit = strtol(np, &cp, 0);
 146                         if (errno != 0 || cp == np) {
 147                                 err = EUNIT;
 148                                 goto fail;
 149                         }
 150                 }
 151                 if (*cp != '\0' && *cp != ':') {
 152                         err = EINVAL;
 153                         goto fail;
 154                 }
 155
 156                 idev->d_unit = unit;
 157                 if (path != NULL)
 158                         *path = (*cp == '\0') ? cp : cp + 1;
 159                 break;
 160         }
 161
 162         idev->d_dev = dv;
 163         idev->d_type = dv->dv_type;
 164
 165         if (dev != NULL)
 166                 *dev = idev;
 167         else
 168                 free(idev);
 169         return (0);
 170
 171 fail:
 172         free(idev);
 173         return (err);
 174 }
 175
 176 char *
 177 efi_fmtdev(void *vdev)
 178 {
 179         struct devdesc *dev = (struct devdesc *)vdev;
 180         static char buf[SPECNAMELEN + 1];
 181
 182         switch (dev->d_type) {
 183         case DEVT_NONE:
 184                 strlcpy(buf, "(no device)", sizeof (buf));
 185                 break;
 186
 187         case DEVT_DISK:
 188                 return (disk_fmtdev(vdev));
 189
 190         case DEVT_ZFS:
 191                 return (zfs_fmtdev(dev));
 192
 193         default:
 194                 snprintf(buf, sizeof (buf), "%s%d:", dev->d_dev->dv_name,
 195                     dev->d_unit);
 196                 break;
 197         }
 198
 199         return (buf);
 200 }
 201
 202 /*
 203  * Set currdev to suit the value being supplied in (value)
 204  */
 205 int
 206 efi_setcurrdev(struct env_var *ev, int flags, const void *value)
 207 {
 208         struct devdesc *ncurr;
 209         int rv;
 210
 211         rv = efi_parsedev(&ncurr, value, NULL);
 212         if (rv != 0)
 213                 return (rv);
 214
 215         free(ncurr);
 216         env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
 217         return (0);
 218 }