summaryrefslogtreecommitdiff
path: root/src/dissect/dissect.c
blob: 50de0afce6f006cac3d36b72434f51a04618e82d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
/* SPDX-License-Identifier: LGPL-2.1+ */

#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 "main-func.h"
#include "string-util.h"
#include "strv.h"
#include "user-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_REQUIRE_ROOT|DISSECT_IMAGE_DISCARD_ON_LOOP;
static void *arg_root_hash = NULL;
static size_t arg_root_hash_size = 0;

STATIC_DESTRUCTOR_REGISTER(arg_root_hash, freep);

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
                                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                                       "Unknown --discard= parameter: %s",
                                                       optarg);
                        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': %m", 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)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected a file path as only argument.");

                arg_image = argv[optind];
                arg_flags |= DISSECT_IMAGE_READ_ONLY;
                break;

        case ACTION_MOUNT:
                if (optind + 2 != argc)
                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
                                               "Expected a file path and mount point path as only arguments.");

                arg_image = argv[optind];
                arg_path = argv[optind + 1];
                break;

        default:
                assert_not_reached("Unknown action.");
        }

        return 1;
}

static int run(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)
                return r;

        r = loop_device_make_by_path(arg_image, (arg_flags & DISSECT_IMAGE_READ_ONLY) ? O_RDONLY : O_RDWR, &d);
        if (r < 0)
                return log_error_errno(r, "Failed to set up loopback device: %m");

        if (!arg_root_hash) {
                r = root_hash_load(arg_image, &arg_root_hash, &arg_root_hash_size);
                if (r < 0)
                        return log_error_errno(r, "Failed to read root hash file for %s: %m", arg_image);
        }

        r = dissect_image_and_warn(d->fd, arg_image, arg_root_hash, arg_root_hash_size, arg_flags, &m);
        if (r < 0)
                return r;

        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 (!sd_id128_is_null(p->uuid))
                                printf(" (UUID " SD_ID128_FORMAT_STR ")", SD_ID128_FORMAT_VAL(p->uuid));

                        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');
                }

                r = dissected_image_acquire_metadata(m);
                if (r < 0)
                        return log_error_errno(r, "Failed to acquire image metadata: %m");

                if (m->hostname)
                        printf("  Hostname: %s\n", m->hostname);

                if (!sd_id128_is_null(m->machine_id))
                        printf("Machine ID: " SD_ID128_FORMAT_STR "\n", SD_ID128_FORMAT_VAL(m->machine_id));

                if (!strv_isempty(m->machine_info)) {
                        char **p, **q;

                        STRV_FOREACH_PAIR(p, q, m->machine_info)
                                printf("%s %s=%s\n",
                                       p == m->machine_info ? "Mach. Info:" : "           ",
                                       *p, *q);
                }

                if (!strv_isempty(m->os_release)) {
                        char **p, **q;

                        STRV_FOREACH_PAIR(p, q, m->os_release)
                                printf("%s %s=%s\n",
                                       p == m->os_release ? "OS Release:" : "           ",
                                       *p, *q);
                }

                break;
        }

        case ACTION_MOUNT:
                r = dissected_image_decrypt_interactively(m, NULL, arg_root_hash, arg_root_hash_size, arg_flags, &di);
                if (r < 0)
                        return r;

                r = dissected_image_mount(m, arg_path, UID_INVALID, arg_flags);
                if (r < 0)
                        return log_error_errno(r, "Failed to mount image: %m");

                if (di) {
                        r = decrypted_image_relinquish(di);
                        if (r < 0)
                                return log_error_errno(r, "Failed to relinquish DM devices: %m");
                }

                loop_device_relinquish(d);
                break;

        default:
                assert_not_reached("Unknown action.");
        }

        return 0;
}

DEFINE_MAIN_FUNCTION(run);