2 * Copyright (c) 2017 Netflix, Inc.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
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11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
29 #include <sys/param.h>
30 #include <sys/ucred.h>
31 #include <sys/mount.h>
46 #include "efi-osdep.h"
47 #include "efivar-dp.h"
49 #include "uefi-dplib.h"
51 #define MAX_DP_SANITY 4096 /* Biggest device path in bytes */
52 #define MAX_DP_TEXT_LEN 4096 /* Longest string rep of dp */
55 #define G_LABEL "LABEL"
59 geom_pp_attr(struct gmesh *mesh, struct gprovider *pp, const char *attr)
63 LIST_FOREACH(conf, &pp->lg_config, lg_config) {
64 if (strcmp(conf->lg_name, attr) != 0)
66 return (conf->lg_val);
71 static struct gprovider *
72 find_provider_by_efimedia(struct gmesh *mesh, const char *efimedia)
74 struct gclass *classp;
80 * Find the partition class so we can search it...
82 LIST_FOREACH(classp, &mesh->lg_class, lg_class) {
83 if (strcasecmp(classp->lg_name, G_PART) == 0)
90 * Each geom will have a number of providers, search each
91 * one of them for the efimedia that matches.
93 /* XXX just used gpart class since I know it's the only one, but maybe I should search all classes */
94 LIST_FOREACH(gp, &classp->lg_geom, lg_geom) {
95 LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
96 val = geom_pp_attr(mesh, pp, "efimedia");
99 if (strcasecmp(efimedia, val) == 0)
107 static struct gprovider *
108 find_provider_by_name(struct gmesh *mesh, const char *name)
110 struct gclass *classp;
112 struct gprovider *pp;
114 LIST_FOREACH(classp, &mesh->lg_class, lg_class) {
115 LIST_FOREACH(gp, &classp->lg_geom, lg_geom) {
116 LIST_FOREACH(pp, &gp->lg_provider, lg_provider) {
117 if (strcmp(pp->lg_name, name) == 0)
128 efi_hd_to_unix(struct gmesh *mesh, const_efidp dp, char **dev, char **relpath, char **abspath)
131 const_efidp media, file, walker;
133 char buf[MAX_DP_TEXT_LEN];
135 struct gprovider *pp, *provider;
136 struct gconsumer *cp;
142 * Now, we can either have a filepath node next, or the end.
143 * Otherwise, it's an error.
145 walker = (const_efidp)NextDevicePathNode(walker);
146 if ((uintptr_t)walker - (uintptr_t)dp > MAX_DP_SANITY)
148 if (DevicePathType(walker) == MEDIA_DEVICE_PATH &&
149 DevicePathSubType(walker) == MEDIA_FILEPATH_DP)
151 else if (DevicePathType(walker) == MEDIA_DEVICE_PATH &&
152 DevicePathType(walker) == END_DEVICE_PATH_TYPE)
158 * Format this node. We're going to look for it as a efimedia
159 * attribute of some geom node. Once we find that node, we use it
160 * as the device it comes from, at least provisionally.
162 len = efidp_format_device_path_node(buf, sizeof(buf), media);
163 if (len > sizeof(buf))
166 pp = find_provider_by_efimedia(mesh, buf);
172 *dev = strdup(pp->lg_name);
179 * No file specified, just return the device. Don't even look
180 * for a mountpoint. XXX Sane?
186 * Now extract the relative path. The next node in the device path should
187 * be a filesystem node. If not, we have issues.
189 *relpath = efidp_extract_file_path(file);
190 if (*relpath == NULL) {
194 for (pwalk = *relpath; *pwalk; pwalk++)
199 * To find the absolute path, we have to look for where we're mounted.
200 * We only look a little hard, since looking too hard can come up with
201 * false positives (imagine a graid, one of whose devices is *dev).
203 n = getfsstat(NULL, 0, MNT_NOWAIT) + 1;
208 mntlen = sizeof(struct statfs) * n;
209 mnt = malloc(mntlen);
210 n = getfsstat(mnt, mntlen, MNT_NOWAIT);
216 for (i = 0; i < n; i++) {
218 * Skip all pseudo filesystems. This also skips the real filesytsem
219 * of ZFS. There's no EFI designator for ZFS in the standard, so
220 * we'll need to invent one, but its decoding will be handled in
221 * a separate function.
223 if (mnt[i].f_mntfromname[0] != '/')
227 * First see if it is directly attached
229 if (strcmp(provider->lg_name, mnt[i].f_mntfromname + 5) == 0)
233 * Next see if it is attached via one of the physical disk's
236 LIST_FOREACH(cp, &provider->lg_consumers, lg_consumer) {
237 pp = cp->lg_provider;
238 if (strcmp(pp->lg_geom->lg_class->lg_name, G_LABEL) != 0)
240 if (strcmp(g_device_path(pp->lg_name), mnt[i].f_mntfromname) == 0)
243 /* Not the one, try the next mount point */
248 * No mountpoint found, no absolute path possible
254 * Construct absolute path and we're finally done.
256 if (strcmp(mnt[i].f_mntonname, "/") == 0)
257 asprintf(abspath, "/%s", *relpath);
259 asprintf(abspath, "%s/%s", mnt[i].f_mntonname, *relpath);
272 * Translate the passed in device_path to a unix path via the following
275 * If dp, dev or path NULL, return EDOOFUS. XXX wise?
277 * Set *path = NULL; *dev = NULL;
279 * Walk through the device_path until we find either a media device path.
280 * Return EINVAL if not found. Return EINVAL if walking dp would
281 * land us more than sanity size away from the start (4k).
283 * If we find a media descriptor, we search through the geom mesh to see if we
284 * can find a matching node. If no match is found in the mesh that matches,
287 * Once we find a matching node, we search to see if there is a filesystem
288 * mounted on it. If we find nothing, then search each of the devices that are
289 * mounted to see if we can work up the geom tree to find the matching node. if
290 * we still can't find anything, *dev = sprintf("/dev/%s", provider_name
291 * of the original node we found), but return ENOTBLK.
293 * Record the dev of the mountpoint in *dev.
295 * Once we find something, check to see if the next node in the device path is
296 * the end of list. If so, return the mountpoint.
298 * If the next node isn't a File path node, return EFTYPE.
300 * Extract the path from the File path node(s). translate any \ file separators
301 * to /. Append the result to the mount point. Copy the resulting path into
302 * *path. Stat that path. If it is not found, return the errorr from stat.
304 * Finally, check to make sure the resulting path is still on the same
305 * device. If not, return ENODEV.
307 * Otherwise return 0.
309 * The dev or full path that's returned is malloced, so needs to be freed when
310 * the caller is done about it. Unlike many other functions, we can return data
311 * with an error code, so pay attention.
314 efivar_device_path_to_unix_path(const_efidp dp, char **dev, char **relpath, char **abspath)
321 * Sanity check args, fail early
323 if (dp == NULL || dev == NULL || relpath == NULL || abspath == NULL)
331 * Find the first media device path we can. If we go too far,
332 * assume the passed in device path is bogus. If we hit the end
333 * then we didn't find a media device path, so signal that error.
336 while (DevicePathType(walker) != MEDIA_DEVICE_PATH &&
337 DevicePathType(walker) != END_DEVICE_PATH_TYPE) {
338 walker = (const_efidp)NextDevicePathNode(walker);
339 if ((uintptr_t)walker - (uintptr_t)dp > MAX_DP_SANITY)
342 if (DevicePathType(walker) != MEDIA_DEVICE_PATH)
346 * There's several types of media paths. We're only interested in the
347 * hard disk path, as it's really the only relevant one to booting. The
348 * CD path just might also be relevant, and would be easy to add, but
349 * isn't supported. A file path too is relevant, but at this stage, it's
350 * premature because we're trying to translate a specification for a device
351 * and path on that device into a unix path, or at the very least, a
352 * geom device : path-on-device.
354 * Also, ZFS throws a bit of a monkey wrench in here since it doesn't have
355 * a device path type (it creates a new virtual device out of one or more
358 * For all of them, we'll need to know the geoms, so allocate / free the
359 * geom mesh here since it's safer than doing it in each sub-function
360 * which may have many error exits.
362 if (geom_gettree(&mesh))
366 if (DevicePathSubType(walker) == MEDIA_HARDDRIVE_DP)
367 rv = efi_hd_to_unix(&mesh, walker, dev, relpath, abspath);
369 else if (is_cdrom_device(walker))
370 rv = efi_cdrom_to_unix(&mesh, walker, dev, relpath, abspath);
371 else if (is_floppy_device(walker))
372 rv = efi_floppy_to_unix(&mesh, walker, dev, relpath, abspath);
373 else if (is_zpool_device(walker))
374 rv = efi_zpool_to_unix(&mesh, walker, dev, relpath, abspath);
376 geom_deletetree(&mesh);
382 * Construct the EFI path to a current unix path as follows.
384 * The path may be of one of three forms:
385 * 1) /path/to/file -- full path to a file. The file need not be present,
386 * but /path/to must be. It must reside on a local filesystem
387 * mounted on a GPT or MBR partition.
388 * 2) //path/to/file -- Shorthand for 'On the EFI partition, \path\to\file'
389 * where 'The EFI Partition' is a partiton that's type is 'efi'
390 * on the same disk that / is mounted from. If there are multiple
391 * or no 'efi' parittions on that disk, or / isn't on a disk that
392 * we can trace back to a physical device, an error will result
393 * 3) [/dev/]geom-name:/path/to/file -- Use the specified partition
394 * (and it must be a GPT or MBR partition) with the specified
395 * path. The latter is not authenticated.
396 * all path forms translate any \ characters to / before further processing.
397 * When a file path node is created, all / characters are translated back
400 * For paths of the first form:
401 * find where the filesystem is mount (either the file directly, or
402 * its parent directory).
403 * translate any logical device name (eg lable) to a physical one
404 * If not possible, return ENXIO
405 * If the physical path is unsupported (Eg not on a GPT or MBR disk),
407 * Create a media device path node.
408 * append the relative path from the mountpoint to the media device node
411 * For paths matching the second form:
412 * find the EFI partition corresponding to the root fileystem.
413 * If none found, return ENXIO
414 * Create a media device path node for the found partition
415 * Append a File Path to the end for the rest of the file.
417 * For paths of the third form
418 * Translate the geom-name passed in into a physical partition
420 * Return ENXIO if the translation fails
421 * Make a media device path for it
422 * append the part after the : as a File path node.
426 path_to_file_dp(const char *relpath)
430 asprintf(&rv, "File(%s)", relpath);
435 find_geom_efi_on_root(struct gmesh *mesh)
439 struct gprovider *pp;
440 // struct ggeom *disk;
441 struct gconsumer *cp;
444 * Find /'s geom. Assume it's mounted on /dev/ and filter out all the
445 * filesystems that aren't.
447 if (statfs("/", &buf) != 0)
449 dev = buf.f_mntfromname;
450 if (*dev != '/' || strncmp(dev, _PATH_DEV, sizeof(_PATH_DEV) - 1) != 0)
452 dev += sizeof(_PATH_DEV) -1;
453 pp = find_provider_by_name(mesh, dev);
458 * If the provider is a LABEL, find it's outer PART class, if any. We
459 * only operate on partitions.
461 if (strcmp(pp->lg_geom->lg_class->lg_name, G_LABEL) == 0) {
462 LIST_FOREACH(cp, &pp->lg_consumers, lg_consumer) {
463 if (strcmp(cp->lg_provider->lg_geom->lg_class->lg_name, G_PART) == 0) {
464 pp = cp->lg_provider;
469 if (strcmp(pp->lg_geom->lg_class->lg_name, G_PART) != 0)
473 /* This doesn't work because we can't get the data to walk UP the tree it seems */
476 * Now that we've found the PART that we have mounted as root, find the
477 * first efi typed partition that's a peer, if any.
479 LIST_FOREACH(cp, &pp->lg_consumers, lg_consumer) {
480 if (strcmp(cp->lg_provider->lg_geom->lg_class->lg_name, G_DISK) == 0) {
481 disk = cp->lg_provider->lg_geom;
485 if (disk == NULL) /* This is very bad -- old nested partitions -- no support ? */
490 /* This doesn't work because we can't get the data to walk UP the tree it seems */
493 * With the disk provider, we can look for its consumers to see if any are the proper type.
495 LIST_FOREACH(pp, &disk->lg_consumer, lg_consumer) {
496 type = geom_pp_attr(mesh, pp, "type");
499 if (strcmp(type, "efi") != 0)
501 efimedia = geom_pp_attr(mesh, pp, "efimedia");
502 if (efimedia == NULL)
504 return strdup(efimedia);
512 find_geom_efimedia(struct gmesh *mesh, const char *dev)
514 struct gprovider *pp;
515 const char *efimedia;
517 pp = find_provider_by_name(mesh, dev);
520 efimedia = geom_pp_attr(mesh, pp, "efimedia");
521 if (efimedia == NULL)
523 return strdup(efimedia);
527 build_dp(const char *efimedia, const char *relpath, efidp *dp)
529 char *fp, *dptxt = NULL, *cp, *rp;
534 rp = strdup(relpath);
535 for (cp = rp; *cp; cp++)
538 fp = path_to_file_dp(rp);
545 asprintf(&dptxt, "%s/%s", efimedia, fp);
547 len = efidp_parse_device_path(dptxt, out, 8192);
568 /* Handles //path/to/file */
570 * Which means: find the disk that has /. Then look for a EFI partition
571 * and use that for the efimedia and /path/to/file as relative to that.
572 * Not sure how ZFS will work here since we can't easily make the leap
573 * to the geom from the zpool.
576 efipart_to_dp(struct gmesh *mesh, char *path, efidp *dp)
578 char *efimedia = NULL;
581 efimedia = find_geom_efi_on_root(mesh);
583 if (efimedia == NULL)
584 efimedia = find_efi_on_zfsroot(dev);
586 if (efimedia == NULL) {
591 rv = build_dp(efimedia, path + 1, dp);
598 /* Handles [/dev/]geom:[/]path/to/file */
599 /* Handles zfs-dataset:[/]path/to/file (this may include / ) */
601 dev_path_to_dp(struct gmesh *mesh, char *path, efidp *dp)
603 char *relpath, *dev, *efimedia = NULL;
606 relpath = strchr(path, ':');
607 assert(relpath != NULL);
611 if (strncmp(dev, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
612 dev += sizeof(_PATH_DEV) -1;
614 efimedia = find_geom_efimedia(mesh, dev);
616 if (efimedia == NULL)
617 find_zfs_efi_media(dev);
619 if (efimedia == NULL) {
623 rv = build_dp(efimedia, relpath, dp);
630 /* Handles /path/to/file */
632 path_to_dp(struct gmesh *mesh, char *path, efidp *dp)
635 char *rp = NULL, *ep, *dev, *efimedia = NULL;
638 rp = realpath(path, NULL);
644 if (statfs(rp, &buf) != 0) {
649 dev = buf.f_mntfromname;
650 if (strncmp(dev, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
651 dev += sizeof(_PATH_DEV) -1;
652 ep = rp + strlen(buf.f_mntonname);
654 efimedia = find_geom_efimedia(mesh, dev);
656 if (efimedia == NULL)
657 find_zfs_efi_media(dev);
659 if (efimedia == NULL) {
664 rv = build_dp(efimedia, ep, dp);
676 efivar_unix_path_to_device_path(const char *path, efidp *dp)
678 char *modpath = NULL, *cp;
683 * Fail early for clearly bogus things
685 if (path == NULL || dp == NULL)
689 * We'll need the goem mesh to grovel through it to find the
690 * efimedia attribute for any devices we find. Grab it here
691 * and release it to simplify the error paths out of the
692 * subordinate functions
694 if (geom_gettree(&mesh))
698 * Convert all \ to /. We'll convert them back again when
699 * we encode the file. Boot loaders are expected to cope.
701 modpath = strdup(path);
704 for (cp = modpath; *cp; cp++)
708 if (modpath[0] == '/' && modpath[1] == '/') /* Handle //foo/bar/baz */
709 rv = efipart_to_dp(&mesh, modpath, dp);
710 else if (strchr(modpath, ':')) /* Handle dev:/bar/baz */
711 rv = dev_path_to_dp(&mesh, modpath, dp);
712 else /* Handle /a/b/c */
713 rv = path_to_dp(&mesh, modpath, dp);
716 geom_deletetree(&mesh);