diff options
Diffstat (limited to 'src/dissect')
| l--------- | src/dissect/Makefile | 1 | ||||
| -rw-r--r-- | src/dissect/dissect.c | 271 |
2 files changed, 272 insertions, 0 deletions
diff --git a/src/dissect/Makefile b/src/dissect/Makefile new file mode 120000 index 0000000000..d0b0e8e008 --- /dev/null +++ b/src/dissect/Makefile @@ -0,0 +1 @@ +../Makefile
\ No newline at end of file diff --git a/src/dissect/dissect.c b/src/dissect/dissect.c new file mode 100644 index 0000000000..e3c96b7407 --- /dev/null +++ b/src/dissect/dissect.c @@ -0,0 +1,271 @@ +/*** + 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: + if (streq(optarg, "disabled")) + arg_flags &= ~(DISSECT_IMAGE_DISCARD_ON_LOOP|DISSECT_IMAGE_DISCARD|DISSECT_IMAGE_DISCARD_ON_CRYPTO); + else if (streq(optarg, "loop")) + arg_flags = (arg_flags & ~(DISSECT_IMAGE_DISCARD|DISSECT_IMAGE_DISCARD_ON_CRYPTO)) | DISSECT_IMAGE_DISCARD_ON_LOOP; + else if (streq(optarg, "all")) + arg_flags = (arg_flags & ~(DISSECT_IMAGE_DISCARD_ON_CRYPTO)) | DISSECT_IMAGE_DISCARD_ON_LOOP | DISSECT_IMAGE_DISCARD; + else if (streq(optarg, "crypt")) + arg_flags |= DISSECT_IMAGE_DISCARD_ON_LOOP | DISSECT_IMAGE_DISCARD | DISSECT_IMAGE_DISCARD_ON_CRYPTO; + else { + log_error("Unknown --discard= parameter: %s", optarg); + return -EINVAL; + } + + 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; +} |