/* libguestfs - the guestfsd daemon
- * Copyright (C) 2009 Red Hat Inc.
+ * Copyright (C) 2009 Red Hat Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <mntent.h>
#include "daemon.h"
#include "actions.h"
-/* You must mount something on "/" first, hence: */
-int root_mounted = 0;
+/* You must mount something on "/" first before many operations.
+ * Hence we have an internal function which can test if something is
+ * mounted on *or under* the sysroot directory. (It has to be *or
+ * under* because of mkmountpoint and friends).
+ */
+int
+is_root_mounted (void)
+{
+ FILE *fp;
+ struct mntent *m;
+
+ /* NB: Eventually we should aim to parse /proc/self/mountinfo, but
+ * that requires custom parsing code.
+ */
+ fp = setmntent ("/proc/mounts", "r");
+ if (fp == NULL) {
+ perror ("/proc/mounts");
+ exit (EXIT_FAILURE);
+ }
+
+ while ((m = getmntent (fp)) != NULL) {
+ /* Allow a mount directory like "/sysroot". */
+ if (sysroot_len > 0 && STREQ (m->mnt_dir, sysroot)) {
+ gotit:
+ endmntent (fp);
+ return 1;
+ }
+ /* Or allow a mount directory like "/sysroot/...". */
+ if (STRPREFIX (m->mnt_dir, sysroot) && m->mnt_dir[sysroot_len] == '/')
+ goto gotit;
+ }
+
+ endmntent (fp);
+ return 0;
+}
/* The "simple mount" call offers no complex options, you can just
* mount a device on a mountpoint. The variations like mount_ro,
int
do_mount_vfs (const char *options, const char *vfstype,
- const char *device, const char *mountpoint)
+ const char *device, const char *mountpoint)
{
- int len, r, is_root;
+ int r;
char *mp;
char *error;
+ struct stat statbuf;
- is_root = strcmp (mountpoint, "/") == 0;
-
- if (!root_mounted && !is_root) {
- reply_with_error ("mount: you must mount something on / first");
- return -1;
- }
-
- len = strlen (mountpoint) + 9;
+ ABS_PATH (mountpoint, , return -1);
- mp = malloc (len);
+ mp = sysroot_path (mountpoint);
if (!mp) {
reply_with_perror ("malloc");
return -1;
}
- snprintf (mp, len, "/sysroot%s", mountpoint);
+ /* Check the mountpoint exists and is a directory. */
+ if (stat (mp, &statbuf) == -1) {
+ reply_with_perror ("mount: %s", mountpoint);
+ free (mp);
+ return -1;
+ }
+ if (!S_ISDIR (statbuf.st_mode)) {
+ reply_with_perror ("mount: %s: mount point is not a directory", mountpoint);
+ free (mp);
+ return -1;
+ }
if (vfstype)
r = command (NULL, &error,
- "mount", "-o", options, "-t", vfstype, device, mp, NULL);
+ "mount", "-o", options, "-t", vfstype, device, mp, NULL);
else
r = command (NULL, &error,
- "mount", "-o", options, device, mp, NULL);
+ "mount", "-o", options, device, mp, NULL);
+ free (mp);
if (r == -1) {
- reply_with_error ("mount: %s on %s: %s", device, mountpoint, error);
+ reply_with_error ("%s on %s: %s", device, mountpoint, error);
free (error);
return -1;
}
- if (is_root)
- root_mounted = 1;
-
+ free (error);
return 0;
}
int
do_mount_options (const char *options, const char *device,
- const char *mountpoint)
+ const char *mountpoint)
{
return do_mount_vfs (options, NULL, device, mountpoint);
}
int
do_umount (const char *pathordevice)
{
- int len, freeit = 0, r;
- char *buf;
+ int r;
char *err;
+ char *buf;
+ int is_dev;
- if (strncmp (pathordevice, "/dev/", 5) == 0)
- buf = (char *) pathordevice;
- else {
- len = strlen (pathordevice) + 9;
- freeit = 1;
- buf = malloc (len);
- if (buf == NULL) {
- reply_with_perror ("malloc");
- return -1;
- }
- snprintf (buf, len, "/sysroot%s", pathordevice);
+ is_dev = STREQLEN (pathordevice, "/dev/", 5);
+ buf = is_dev ? strdup (pathordevice)
+ : sysroot_path (pathordevice);
+ if (buf == NULL) {
+ reply_with_perror ("malloc");
+ return -1;
}
+ if (is_dev)
+ RESOLVE_DEVICE (buf, , { free (buf); return -1; });
+
r = command (NULL, &err, "umount", buf, NULL);
- if (freeit) free (buf);
+ free (buf);
+
if (r == -1) {
- reply_with_error ("umount: %s: %s", pathordevice, err);
+ reply_with_error ("%s: %s", pathordevice, err);
free (err);
return -1;
}
free (err);
- /* update root_mounted? */
-
return 0;
}
-char **
-do_mounts (void)
+/* Implement 'mounts' (mp==0) and 'mountpoints' (mp==1) calls. */
+static char **
+mounts_or_mountpoints (int mp)
{
- char *out, *err;
- int r;
+ FILE *fp;
+ struct mntent *m;
char **ret = NULL;
int size = 0, alloc = 0;
- char *p, *pend, *p2;
+ size_t i;
+ int r;
- r = command (&out, &err, "mount", NULL);
- if (r == -1) {
- reply_with_error ("mount: %s", err);
- free (out);
- free (err);
- return NULL;
+ /* NB: Eventually we should aim to parse /proc/self/mountinfo, but
+ * that requires custom parsing code.
+ */
+ fp = setmntent ("/proc/mounts", "r");
+ if (fp == NULL) {
+ perror ("/proc/mounts");
+ exit (EXIT_FAILURE);
}
- free (err);
-
- p = out;
- while (p) {
- pend = strchr (p, '\n');
- if (pend) {
- *pend = '\0';
- pend++;
- }
-
- /* Lines have the format:
- * /dev/foo on /mountpoint type ...
- */
- p2 = strstr (p, " on /sysroot");
- if (p2 != NULL) {
- *p2 = '\0';
- if (add_string (&ret, &size, &alloc, p) == -1) {
- free (out);
- return NULL;
+ while ((m = getmntent (fp)) != NULL) {
+ /* Allow a mount directory like "/sysroot". */
+ if (sysroot_len > 0 && STREQ (m->mnt_dir, sysroot)) {
+ if (add_string (&ret, &size, &alloc, m->mnt_fsname) == -1) {
+ error:
+ endmntent (fp);
+ return NULL;
}
+ if (mp &&
+ add_string (&ret, &size, &alloc, "/") == -1)
+ goto error;
+ }
+ /* Or allow a mount directory like "/sysroot/...". */
+ if (STRPREFIX (m->mnt_dir, sysroot) && m->mnt_dir[sysroot_len] == '/') {
+ if (add_string (&ret, &size, &alloc, m->mnt_fsname) == -1)
+ goto error;
+ if (mp &&
+ add_string (&ret, &size, &alloc, &m->mnt_dir[sysroot_len]) == -1)
+ goto error;
}
-
- p = pend;
}
- free (out);
+ endmntent (fp);
if (add_string (&ret, &size, &alloc, NULL) == -1)
return NULL;
+ /* Convert /dev/mapper LV paths into canonical paths (RHBZ#646432). */
+ for (i = 0; ret[i] != NULL; i += mp ? 2 : 1) {
+ if (STRPREFIX (ret[i], "/dev/mapper/") || STRPREFIX (ret[i], "/dev/dm-")) {
+ char *canonical;
+ r = lv_canonical (ret[i], &canonical);
+ if (r == -1) {
+ free_strings (ret);
+ return NULL;
+ }
+ if (r == 1) {
+ free (ret[i]);
+ ret[i] = canonical;
+ }
+ /* Ignore the case where r == 0. This might happen where
+ * eg. a LUKS /dev/mapper device is mounted, but that won't
+ * correspond to any LV.
+ */
+ }
+ }
+
return ret;
}
+char **
+do_mounts (void)
+{
+ return mounts_or_mountpoints (0);
+}
+
+char **
+do_mountpoints (void)
+{
+ return mounts_or_mountpoints (1);
+}
+
/* Unmount everything mounted under /sysroot.
*
* We have to unmount in the correct order, so we sort the paths by
int
do_umount_all (void)
{
- char *out, *err;
- int i, r;
+ FILE *fp;
+ struct mntent *m;
char **mounts = NULL;
int size = 0, alloc = 0;
- char *p, *p2, *p3, *pend;
+ char *err;
+ int i, r;
- r = command (&out, &err, "mount", NULL);
- if (r == -1) {
- reply_with_error ("mount: %s", err);
- free (out);
- free (err);
- return -1;
+ /* NB: Eventually we should aim to parse /proc/self/mountinfo, but
+ * that requires custom parsing code.
+ */
+ fp = setmntent ("/proc/mounts", "r");
+ if (fp == NULL) {
+ perror ("/proc/mounts");
+ exit (EXIT_FAILURE);
}
- free (err);
-
- p = out;
- while (p) {
- pend = strchr (p, '\n');
- if (pend) {
- *pend = '\0';
- pend++;
+ while ((m = getmntent (fp)) != NULL) {
+ /* Allow a mount directory like "/sysroot". */
+ if (sysroot_len > 0 && STREQ (m->mnt_dir, sysroot)) {
+ if (add_string (&mounts, &size, &alloc, m->mnt_dir) == -1) {
+ endmntent (fp);
+ return -1;
+ }
}
-
- /* Lines have the format:
- * /dev/foo on /mountpoint type ...
- */
- p2 = strstr (p, " on /sysroot");
- if (p2 != NULL) {
- p2 += 4;
- p3 = p2 + strcspn (p2, " ");
- *p3 = '\0';
- if (add_string (&mounts, &size, &alloc, p2) == -1) {
- free (out);
- return -1;
+ /* Or allow a mount directory like "/sysroot/...". */
+ if (STRPREFIX (m->mnt_dir, sysroot) && m->mnt_dir[sysroot_len] == '/') {
+ if (add_string (&mounts, &size, &alloc, m->mnt_dir) == -1) {
+ endmntent (fp);
+ return -1;
}
}
-
- p = pend;
}
- free (out);
+
+ endmntent (fp);
qsort (mounts, size, sizeof (char *), compare_longest_first);
free_stringslen (mounts, size);
- /* We've unmounted root now, so ... */
- root_mounted = 0;
+ return 0;
+}
+
+/* Mount using the loopback device. You can't use the generic
+ * do_mount call for this because the first parameter isn't a
+ * device.
+ */
+int
+do_mount_loop (const char *file, const char *mountpoint)
+{
+ int r;
+ char *buf, *mp;
+ char *error;
+
+ /* We have to prefix /sysroot on both the filename and the mountpoint. */
+ mp = sysroot_path (mountpoint);
+ if (!mp) {
+ reply_with_perror ("malloc");
+ return -1;
+ }
+
+ buf = sysroot_path (file);
+ if (!buf) {
+ reply_with_perror ("malloc");
+ free (mp);
+ return -1;
+ }
+
+ r = command (NULL, &error, "mount", "-o", "loop", buf, mp, NULL);
+ free (mp);
+ free (buf);
+ if (r == -1) {
+ reply_with_error ("%s on %s: %s", file, mountpoint, error);
+ free (error);
+ return -1;
+ }
+
+ free (error);
+ return 0;
+}
+
+/* Specialized calls mkmountpoint and rmmountpoint are really
+ * variations on mkdir and rmdir which do no checking of the
+ * is_root_mounted() flag.
+ */
+int
+do_mkmountpoint (const char *path)
+{
+ int r;
+
+ /* NEED_ROOT (return -1); - we don't want this test for this call. */
+ ABS_PATH (path, , return -1);
+
+ CHROOT_IN;
+ r = mkdir (path, 0777);
+ CHROOT_OUT;
+
+ if (r == -1) {
+ reply_with_perror ("%s", path);
+ return -1;
+ }
+
+ return 0;
+}
+
+int
+do_rmmountpoint (const char *path)
+{
+ int r;
+
+ /* NEED_ROOT (return -1); - we don't want this test for this call. */
+ ABS_PATH (path, , return -1);
+
+ CHROOT_IN;
+ r = rmdir (path);
+ CHROOT_OUT;
+
+ if (r == -1) {
+ reply_with_perror ("%s", path);
+ return -1;
+ }
return 0;
}