/***
This file is part of systemd.
Copyright 2016 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <fcntl.h>
#include <stdio.h>
#include <getopt.h>
#include "architecture.h"
#include "dissect-image.h"
#include "hexdecoct.h"
#include "log.h"
#include "loop-util.h"
#include "string-util.h"
#include "util.h"
static enum {
ACTION_DISSECT,
ACTION_MOUNT,
} arg_action = ACTION_DISSECT;
static const char *arg_image = NULL;
static const char *arg_path = NULL;
static DissectImageFlags arg_flags = DISSECT_IMAGE_DISCARD_ON_LOOP;
static void *arg_root_hash = NULL;
static size_t arg_root_hash_size = 0;
static void help(void) {
printf("%s [OPTIONS...] IMAGE\n"
"%s [OPTIONS...] --mount IMAGE PATH\n"
"Dissect a file system OS image.\n\n"
" -h --help Show this help\n"
" --version Show package version\n"
" -m --mount Mount the image to the specified directory\n"
" -r --read-only Mount read-only\n"
" --discard=MODE Choose 'discard' mode (disabled, loop, all, crypto)\n"
" --root-hash=HASH Specify root hash for verity\n",
program_invocation_short_name,
program_invocation_short_name);
}
static int parse_argv(int argc, char *argv[]) {
enum {
ARG_VERSION = 0x100,
ARG_DISCARD,
ARG_ROOT_HASH,
};
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, ARG_VERSION },
{ "mount", no_argument, NULL, 'm' },
{ "read-only", no_argument, NULL, 'r' },
{ "discard", required_argument, NULL, ARG_DISCARD },
{ "root-hash", required_argument, NULL, ARG_ROOT_HASH },
{}
};
int c, r;
assert(argc >= 0);
assert(argv);
while ((c = getopt_long(argc, argv, "hmr", options, NULL)) >= 0) {
switch (c) {
case 'h':
help();
return 0;
case ARG_VERSION:
return version();
case 'm':
arg_action = ACTION_MOUNT;
break;
case 'r':
arg_flags |= DISSECT_IMAGE_READ_ONLY;
break;
case ARG_DISCARD: {
DissectImageFlags flags;
if (streq(optarg, "disabled"))
flags = 0;
else if (streq(optarg, "loop"))
flags = DISSECT_IMAGE_DISCARD_ON_LOOP;
else if (streq(optarg, "all"))
flags = DISSECT_IMAGE_DISCARD_ON_LOOP | DISSECT_IMAGE_DISCARD;
else if (streq(optarg, "crypt"))
flags = DISSECT_IMAGE_DISCARD_ANY;
else {
log_error("Unknown --discard= parameter: %s", optarg);
return -EINVAL;
}
arg_flags = (arg_flags & ~DISSECT_IMAGE_DISCARD_ANY) | flags;
break;
}
case ARG_ROOT_HASH: {
void *p;
size_t l;
r = unhexmem(optarg, strlen(optarg), &p, &l);
if (r < 0)
return log_error_errno(r, "Failed to parse root hash: %s", optarg);
if (l < sizeof(sd_id128_t)) {
log_error("Root hash must be at least 128bit long: %s", optarg);
free(p);
return -EINVAL;
}
free(arg_root_hash);
arg_root_hash = p;
arg_root_hash_size = l;
break;
}
case '?':
return -EINVAL;
default:
assert_not_reached("Unhandled option");
}
}
switch (arg_action) {
case ACTION_DISSECT:
if (optind + 1 != argc) {
log_error("Expected a file path as only argument.");
return -EINVAL;
}
arg_image = argv[optind];
arg_flags |= DISSECT_IMAGE_READ_ONLY;
break;
case ACTION_MOUNT:
if (optind + 2 != argc) {
log_error("Expected a file path and mount point path as only arguments.");
return -EINVAL;
}
arg_image = argv[optind];
arg_path = argv[optind + 1];
break;
default:
assert_not_reached("Unknown action.");
}
return 1;
}
int main(int argc, char *argv[]) {
_cleanup_(loop_device_unrefp) LoopDevice *d = NULL;
_cleanup_(decrypted_image_unrefp) DecryptedImage *di = NULL;
_cleanup_(dissected_image_unrefp) DissectedImage *m = NULL;
int r;
log_parse_environment();
log_open();
r = parse_argv(argc, argv);
if (r <= 0)
goto finish;
r = loop_device_make_by_path(arg_image, (arg_flags & DISSECT_IMAGE_READ_ONLY) ? O_RDONLY : O_RDWR, &d);
if (r < 0) {
log_error_errno(r, "Failed to set up loopback device: %m");
goto finish;
}
r = dissect_image(d->fd, arg_root_hash, arg_root_hash_size, &m);
if (r == -ENOPKG) {
log_error_errno(r, "Couldn't identify a suitable partition table or file system in %s.", arg_image);
goto finish;
}
if (r == -EADDRNOTAVAIL) {
log_error_errno(r, "No root partition for specified root hash found in %s.", arg_image);
goto finish;
}
if (r < 0) {
log_error_errno(r, "Failed to dissect image: %m");
goto finish;
}
switch (arg_action) {
case ACTION_DISSECT: {
unsigned i;
for (i = 0; i < _PARTITION_DESIGNATOR_MAX; i++) {
DissectedPartition *p = m->partitions + i;
int k;
if (!p->found)
continue;
printf("Found %s '%s' partition",
p->rw ? "writable" : "read-only",
partition_designator_to_string(i));
if (p->fstype)
printf(" of type %s", p->fstype);
if (p->architecture != _ARCHITECTURE_INVALID)
printf(" for %s", architecture_to_string(p->architecture));
k = PARTITION_VERITY_OF(i);
if (k >= 0)
printf(" %s verity", m->partitions[k].found ? "with" : "without");
if (p->partno >= 0)
printf(" on partition #%i", p->partno);
if (p->node)
printf(" (%s)", p->node);
putchar('\n');
}
break;
}
case ACTION_MOUNT:
r = dissected_image_decrypt_interactively(m, NULL, arg_root_hash, arg_root_hash_size, arg_flags, &di);
if (r < 0)
goto finish;
r = dissected_image_mount(m, arg_path, arg_flags);
if (r < 0) {
log_error_errno(r, "Failed to mount image: %m");
goto finish;
}
if (di) {
r = decrypted_image_relinquish(di);
if (r < 0) {
log_error_errno(r, "Failed to relinquish DM devices: %m");
goto finish;
}
}
loop_device_relinquish(d);
break;
default:
assert_not_reached("Unknown action.");
}
finish:
free(arg_root_hash);
return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
}