freebsd-dev/sbin/bectl/bectl.c
Kyle Evans 4163bae030 bectl: document the -r flag to bectl
Independent of all of the commands, bectl itself takes an `-r` flag that
specifies the BE root to use.  This was originally added to facilitate
testing, but it was later discovered to be incredibly useful in other
scenarios; e.g., trying to recover some boot environments in rescue
media.

The "BE root" described here is the parent dataset that holds boot
environments, but I've no idea if that's an accepted definition for that
dataset.

Reviewed by:	gallatin, imp, Pau Amma
MFC after:	1 week
Differential Review:	https://reviews.freebsd.org/D39710
2023-04-26 00:33:25 -05:00

601 lines
13 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2017 Kyle J. Kneitinger <kyle@kneit.in>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/mount.h>
#include <errno.h>
#include <libutil.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <time.h>
#include <unistd.h>
#include <be.h>
#include "bectl.h"
static int bectl_cmd_activate(int argc, char *argv[]);
static int bectl_cmd_check(int argc, char *argv[]);
static int bectl_cmd_create(int argc, char *argv[]);
static int bectl_cmd_destroy(int argc, char *argv[]);
static int bectl_cmd_export(int argc, char *argv[]);
static int bectl_cmd_import(int argc, char *argv[]);
#if SOON
static int bectl_cmd_add(int argc, char *argv[]);
#endif
static int bectl_cmd_mount(int argc, char *argv[]);
static int bectl_cmd_rename(int argc, char *argv[]);
static int bectl_cmd_unmount(int argc, char *argv[]);
libbe_handle_t *be;
int
usage(bool explicit)
{
FILE *fp;
fp = explicit ? stdout : stderr;
fprintf(fp, "%s",
"Usage:\tbectl {-h | -? | subcommand [args...]}\n"
#if SOON
"\tbectl [-r beroot] add (path)*\n"
#endif
"\tbectl [-r beroot] activate [-t] beName\n"
"\tbectl [-r beroot] activate [-T]\n"
"\tbectl [-r beroot] check\n"
"\tbectl [-r beroot] create [-r] [-e {nonActiveBe | beName@snapshot}] beName\n"
"\tbectl [-r beroot] create [-r] beName@snapshot\n"
"\tbectl [-r beroot] destroy [-Fo] {beName | beName@snapshot}\n"
"\tbectl [-r beroot] export sourceBe\n"
"\tbectl [-r beroot] import targetBe\n"
"\tbectl [-r beroot] jail [-bU] [{-o key=value | -u key}]... beName\n"
"\t [utility [argument ...]]\n"
"\tbectl [-r beroot] list [-aDHs] [{-c property | -C property}]\n"
"\tbectl [-r beroot] mount beName [mountpoint]\n"
"\tbectl [-r beroot] rename origBeName newBeName\n"
"\tbectl [-r beroot] {ujail | unjail} {jailID | jailName | beName}\n"
"\tbectl [-r beroot] {umount | unmount} [-f] beName\n");
return (explicit ? 0 : EX_USAGE);
}
/*
* Represents a relationship between the command name and the parser action
* that handles it.
*/
struct command_map_entry {
const char *command;
int (*fn)(int argc, char *argv[]);
/* True if libbe_print_on_error should be disabled */
bool silent;
};
static struct command_map_entry command_map[] =
{
{ "activate", bectl_cmd_activate,false },
{ "create", bectl_cmd_create, false },
{ "destroy", bectl_cmd_destroy, false },
{ "export", bectl_cmd_export, false },
{ "import", bectl_cmd_import, false },
#if SOON
{ "add", bectl_cmd_add, false },
#endif
{ "jail", bectl_cmd_jail, false },
{ "list", bectl_cmd_list, false },
{ "mount", bectl_cmd_mount, false },
{ "rename", bectl_cmd_rename, false },
{ "unjail", bectl_cmd_unjail, false },
{ "unmount", bectl_cmd_unmount, false },
{ "check", bectl_cmd_check, true },
};
static struct command_map_entry *
get_cmd_info(const char *cmd)
{
size_t i;
for (i = 0; i < nitems(command_map); ++i) {
if (strcmp(cmd, command_map[i].command) == 0)
return (&command_map[i]);
}
return (NULL);
}
static int
bectl_cmd_activate(int argc, char *argv[])
{
int err, opt;
bool temp, reset;
temp = false;
reset = false;
while ((opt = getopt(argc, argv, "tT")) != -1) {
switch (opt) {
case 't':
if (reset)
return (usage(false));
temp = true;
break;
case 'T':
if (temp)
return (usage(false));
reset = true;
break;
default:
fprintf(stderr, "bectl activate: unknown option '-%c'\n",
optopt);
return (usage(false));
}
}
argc -= optind;
argv += optind;
if (argc != 1 && (!reset || argc != 0)) {
fprintf(stderr, "bectl activate: wrong number of arguments\n");
return (usage(false));
}
if (reset) {
if ((err = be_deactivate(be, NULL, reset)) == 0)
printf("Temporary activation removed\n");
else
printf("Failed to remove temporary activation\n");
return (err);
}
/* activate logic goes here */
if ((err = be_activate(be, argv[0], temp)) != 0)
/* XXX TODO: more specific error msg based on err */
printf("Did not successfully activate boot environment %s\n",
argv[0]);
else
printf("Successfully activated boot environment %s\n", argv[0]);
if (temp)
printf("for next boot\n");
return (err);
}
/*
* TODO: when only one arg is given, and it contains an "@" the this should
* create that snapshot
*/
static int
bectl_cmd_create(int argc, char *argv[])
{
char snapshot[BE_MAXPATHLEN];
char *atpos, *bootenv, *snapname;
int err, opt;
bool recursive;
snapname = NULL;
recursive = false;
while ((opt = getopt(argc, argv, "e:r")) != -1) {
switch (opt) {
case 'e':
snapname = optarg;
break;
case 'r':
recursive = true;
break;
default:
fprintf(stderr, "bectl create: unknown option '-%c'\n",
optopt);
return (usage(false));
}
}
argc -= optind;
argv += optind;
if (argc != 1) {
fprintf(stderr, "bectl create: wrong number of arguments\n");
return (usage(false));
}
bootenv = *argv;
err = BE_ERR_SUCCESS;
if ((atpos = strchr(bootenv, '@')) != NULL) {
/*
* This is the "create a snapshot variant". No new boot
* environment is to be created here.
*/
*atpos++ = '\0';
err = be_snapshot(be, bootenv, atpos, recursive, NULL);
} else {
if (snapname == NULL)
/* Create from currently booted BE */
err = be_snapshot(be, be_active_path(be), NULL,
recursive, snapshot);
else if (strchr(snapname, '@') != NULL)
/* Create from given snapshot */
strlcpy(snapshot, snapname, sizeof(snapshot));
else
/* Create from given BE */
err = be_snapshot(be, snapname, NULL, recursive,
snapshot);
if (err == BE_ERR_SUCCESS)
err = be_create_depth(be, bootenv, snapshot,
recursive == true ? -1 : 0);
}
switch (err) {
case BE_ERR_SUCCESS:
break;
case BE_ERR_INVALIDNAME:
fprintf(stderr,
"bectl create: boot environment name must not contain spaces\n");
break;
default:
if (atpos != NULL)
fprintf(stderr,
"Failed to create a snapshot '%s' of '%s'\n",
atpos, bootenv);
else if (snapname == NULL)
fprintf(stderr,
"Failed to create bootenv %s\n", bootenv);
else
fprintf(stderr,
"Failed to create bootenv %s from snapshot %s\n",
bootenv, snapname);
}
return (err);
}
static int
bectl_cmd_export(int argc, char *argv[])
{
char *bootenv;
if (argc == 1) {
fprintf(stderr, "bectl export: missing boot environment name\n");
return (usage(false));
}
if (argc > 2) {
fprintf(stderr, "bectl export: extra arguments provided\n");
return (usage(false));
}
bootenv = argv[1];
if (isatty(STDOUT_FILENO)) {
fprintf(stderr, "bectl export: must redirect output\n");
return (EX_USAGE);
}
be_export(be, bootenv, STDOUT_FILENO);
return (0);
}
static int
bectl_cmd_import(int argc, char *argv[])
{
char *bootenv;
int err;
if (argc == 1) {
fprintf(stderr, "bectl import: missing boot environment name\n");
return (usage(false));
}
if (argc > 2) {
fprintf(stderr, "bectl import: extra arguments provided\n");
return (usage(false));
}
bootenv = argv[1];
if (isatty(STDIN_FILENO)) {
fprintf(stderr, "bectl import: input can not be from terminal\n");
return (EX_USAGE);
}
err = be_import(be, bootenv, STDIN_FILENO);
return (err);
}
#if SOON
static int
bectl_cmd_add(int argc, char *argv[])
{
if (argc < 2) {
fprintf(stderr, "bectl add: must provide at least one path\n");
return (usage(false));
}
for (int i = 1; i < argc; ++i) {
printf("arg %d: %s\n", i, argv[i]);
/* XXX TODO catch err */
be_add_child(be, argv[i], true);
}
return (0);
}
#endif
static int
bectl_cmd_destroy(int argc, char *argv[])
{
nvlist_t *props;
char *target, targetds[BE_MAXPATHLEN];
const char *origin;
int err, flags, opt;
flags = 0;
while ((opt = getopt(argc, argv, "Fo")) != -1) {
switch (opt) {
case 'F':
flags |= BE_DESTROY_FORCE;
break;
case 'o':
flags |= BE_DESTROY_ORIGIN;
break;
default:
fprintf(stderr, "bectl destroy: unknown option '-%c'\n",
optopt);
return (usage(false));
}
}
argc -= optind;
argv += optind;
if (argc != 1) {
fprintf(stderr, "bectl destroy: wrong number of arguments\n");
return (usage(false));
}
target = argv[0];
/* We'll emit a notice if there's an origin to be cleaned up */
if ((flags & BE_DESTROY_ORIGIN) == 0 && strchr(target, '@') == NULL) {
flags |= BE_DESTROY_AUTOORIGIN;
if (be_root_concat(be, target, targetds) != 0)
goto destroy;
if (be_prop_list_alloc(&props) != 0)
goto destroy;
if (be_get_dataset_props(be, targetds, props) != 0) {
be_prop_list_free(props);
goto destroy;
}
if (nvlist_lookup_string(props, "origin", &origin) == 0 &&
!be_is_auto_snapshot_name(be, origin))
fprintf(stderr, "bectl destroy: leaving origin '%s' intact\n",
origin);
be_prop_list_free(props);
}
destroy:
err = be_destroy(be, target, flags);
return (err);
}
static int
bectl_cmd_mount(int argc, char *argv[])
{
char result_loc[BE_MAXPATHLEN];
char *bootenv, *mountpoint;
int err, mntflags;
/* XXX TODO: Allow shallow */
mntflags = BE_MNT_DEEP;
if (argc < 2) {
fprintf(stderr, "bectl mount: missing argument(s)\n");
return (usage(false));
}
if (argc > 3) {
fprintf(stderr, "bectl mount: too many arguments\n");
return (usage(false));
}
bootenv = argv[1];
mountpoint = ((argc == 3) ? argv[2] : NULL);
err = be_mount(be, bootenv, mountpoint, mntflags, result_loc);
switch (err) {
case BE_ERR_SUCCESS:
printf("Successfully mounted %s at %s\n", bootenv, result_loc);
break;
default:
fprintf(stderr,
(argc == 3) ? "Failed to mount bootenv %s at %s\n" :
"Failed to mount bootenv %s at temporary path %s\n",
bootenv, mountpoint);
}
return (err);
}
static int
bectl_cmd_rename(int argc, char *argv[])
{
char *dest, *src;
int err;
if (argc < 3) {
fprintf(stderr, "bectl rename: missing argument\n");
return (usage(false));
}
if (argc > 3) {
fprintf(stderr, "bectl rename: too many arguments\n");
return (usage(false));
}
src = argv[1];
dest = argv[2];
err = be_rename(be, src, dest);
switch (err) {
case BE_ERR_SUCCESS:
break;
default:
fprintf(stderr, "Failed to rename bootenv %s to %s\n",
src, dest);
}
return (err);
}
static int
bectl_cmd_unmount(int argc, char *argv[])
{
char *bootenv, *cmd;
int err, flags, opt;
/* Store alias used */
cmd = argv[0];
flags = 0;
while ((opt = getopt(argc, argv, "f")) != -1) {
switch (opt) {
case 'f':
flags |= BE_MNT_FORCE;
break;
default:
fprintf(stderr, "bectl %s: unknown option '-%c'\n",
cmd, optopt);
return (usage(false));
}
}
argc -= optind;
argv += optind;
if (argc != 1) {
fprintf(stderr, "bectl %s: wrong number of arguments\n", cmd);
return (usage(false));
}
bootenv = argv[0];
err = be_unmount(be, bootenv, flags);
switch (err) {
case BE_ERR_SUCCESS:
break;
default:
fprintf(stderr, "Failed to unmount bootenv %s\n", bootenv);
}
return (err);
}
static int
bectl_cmd_check(int argc, char *argv[] __unused)
{
/* The command is left as argv[0] */
if (argc != 1) {
fprintf(stderr, "bectl check: wrong number of arguments\n");
return (usage(false));
}
return (0);
}
int
main(int argc, char *argv[])
{
struct command_map_entry *cmd;
const char *command;
char *root;
int rc;
cmd = NULL;
root = NULL;
if (argc < 2)
return (usage(false));
if (strcmp(argv[1], "-r") == 0) {
if (argc < 4)
return (usage(false));
root = strdup(argv[2]);
command = argv[3];
argc -= 3;
argv += 3;
} else {
command = argv[1];
argc -= 1;
argv += 1;
}
/* Handle command aliases */
if (strcmp(command, "umount") == 0)
command = "unmount";
if (strcmp(command, "ujail") == 0)
command = "unjail";
if ((strcmp(command, "-?") == 0) || (strcmp(command, "-h") == 0))
return (usage(true));
if ((cmd = get_cmd_info(command)) == NULL) {
fprintf(stderr, "Unknown command: %s\n", command);
return (usage(false));
}
if ((be = libbe_init(root)) == NULL) {
if (!cmd->silent)
fprintf(stderr, "libbe_init(\"%s\") failed.\n",
root != NULL ? root : "");
return (-1);
}
libbe_print_on_error(be, !cmd->silent);
rc = cmd->fn(argc, argv);
libbe_close(be);
return (rc);
}