src/cryptsetup.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <string.h>
  23 #include <errno.h>
  24
  25 #include <libcryptsetup.h>
  26
  27 #include "log.h"
  28 #include "util.h"
  29 #include "ask-password-api.h"
  30
  31 static const char *opt_type = NULL; /* LUKS1 or PLAIN */
  32 static char *opt_cipher = NULL;
  33 static char *opt_cipher_mode = NULL;
  34 static unsigned opt_key_size = 0;
  35 static char *opt_hash = NULL;
  36 static unsigned opt_tries = 0;
  37 static bool opt_readonly = false;
  38 static bool opt_verify = false;
  39 static usec_t opt_timeout = 0;
  40
  41 static int parse_one_option(const char *option) {
  42         assert(option);
  43
  44         /* Handled outside of this tool */
  45         if (streq(option, "noauto"))
  46                 return 0;
  47
  48         if (startswith(option, "cipher=")) {
  49                 char *t;
  50
  51                 if (!(t = strdup(option+7)))
  52                         return -ENOMEM;
  53
  54                 free(opt_cipher);
  55                 opt_cipher = t;
  56
  57         } else if (startswith(option, "size=")) {
  58
  59                 if (safe_atou(option+5, &opt_key_size) < 0) {
  60                         log_error("size= parse failure, ignoring.");
  61                         return 0;
  62                 }
  63
  64         } else if (startswith(option, "hash=")) {
  65                 char *t;
  66
  67                 if (!(t = strdup(option+5)))
  68                         return -ENOMEM;
  69
  70                 free(opt_hash);
  71                 opt_hash = t;
  72
  73         } else if (startswith(option, "mode=")) {
  74                 char *t;
  75
  76                 if (!(t = strdup(option+5)))
  77                         return -ENOMEM;
  78
  79                 free(opt_cipher_mode);
  80                 opt_cipher_mode = t;
  81
  82         } else if (startswith(option, "tries=")) {
  83
  84                 if (safe_atou(option+6, &opt_tries) < 0) {
  85                         log_error("tries= parse failure, ignoring.");
  86                         return 0;
  87                 }
  88
  89         } else if (streq(option, "readonly"))
  90                 opt_readonly = true;
  91         else if (streq(option, "verify"))
  92                 opt_verify = true;
  93         else if (streq(option, "luks"))
  94                 opt_type = CRYPT_LUKS1;
  95         else if (streq(option, "plain") ||
  96                  streq(option, "swap") ||
  97                  streq(option, "tmp"))
  98                 opt_type = CRYPT_PLAIN;
  99         else if (startswith(option, "timeout=")) {
 100
 101                 if (parse_usec(option+8, &opt_timeout) < 0) {
 102                         log_error("timeout= parse failure, ignoring.");
 103                         return 0;
 104                 }
 105
 106         } else
 107                 log_error("Encountered unknown /etc/crypttab option '%s', ignoring.", option);
 108
 109         return 0;
 110 }
 111
 112 static int parse_options(const char *options) {
 113         char *state;
 114         char *w;
 115         size_t l;
 116
 117         assert(options);
 118
 119         FOREACH_WORD_SEPARATOR(w, l, options, ",", state) {
 120                 char *o;
 121                 int r;
 122
 123                 if (!(o = strndup(w, l)))
 124                         return -ENOMEM;
 125
 126                 r = parse_one_option(o);
 127                 free(o);
 128
 129                 if (r < 0)
 130                         return r;
 131         }
 132
 133         return 0;
 134 }
 135
 136 static void log_glue(int level, const char *msg, void *usrptr) {
 137         log_debug("%s", msg);
 138 }
 139
 140 int main(int argc, char *argv[]) {
 141         int r = EXIT_FAILURE;
 142         struct crypt_device *cd = NULL;
 143         char *password = NULL;
 144         const char *cipher = NULL, *cipher_mode = NULL, *hash = NULL;
 145         crypt_status_info status;
 146
 147         if (argc < 3) {
 148                 log_error("This program requires at least two arguments.");
 149                 return EXIT_FAILURE;
 150         }
 151
 152         log_set_target(LOG_TARGET_AUTO);
 153         log_parse_environment();
 154         log_open();
 155
 156         if (streq(argv[1], "attach")) {
 157                 uint32_t flags = 0;
 158                 int k;
 159                 unsigned try;
 160                 const char *key_file = NULL;
 161                 usec_t until;
 162
 163                 if (argc < 4) {
 164                         log_error("attach requires at least two arguments.");
 165                         goto finish;
 166                 }
 167
 168                 if (argc >= 5 && argv[4][0] && !streq(argv[4], "-")) {
 169
 170                         if (!path_is_absolute(argv[4]))
 171                                 log_error("Password file path %s is not absolute. Ignoring.", argv[4]);
 172                         else
 173                                 key_file = argv[4];
 174                 }
 175
 176                 if (argc >= 6 && argv[5][0] && !streq(argv[5], "-"))
 177                         parse_options(argv[5]);
 178
 179                 if ((k = crypt_init(&cd, argv[3]))) {
 180                         log_error("crypt_init() failed: %s", strerror(-k));
 181                         goto finish;
 182                 }
 183
 184                 crypt_set_log_callback(cd, log_glue, NULL);
 185
 186                 status = crypt_status(cd, argv[2]);
 187                 if (status == CRYPT_ACTIVE || status == CRYPT_BUSY) {
 188                         log_info("Volume %s already active.", argv[2]);
 189                         r = EXIT_SUCCESS;
 190                         goto finish;
 191                 }
 192
 193                 if (opt_readonly)
 194                         flags |= CRYPT_ACTIVATE_READONLY;
 195
 196                 until = now(CLOCK_MONOTONIC) + (opt_timeout > 0 ? opt_timeout : 60 * USEC_PER_SEC);
 197
 198                 opt_tries = opt_tries > 0 ? opt_tries : 3;
 199                 opt_key_size = (opt_key_size > 0 ? opt_key_size : 256);
 200                 cipher = opt_cipher ? opt_cipher : "aes";
 201                 cipher_mode = opt_cipher_mode ? opt_cipher_mode : "cbc-essiv:sha256";
 202                 hash = opt_hash ? opt_hash : "ripemd160";
 203
 204                 for (try = 0; try < opt_tries; try++) {
 205                         bool pass_volume_key = false;
 206
 207                         free(password);
 208                         password = NULL;
 209
 210                         if (!key_file) {
 211
 212                                 if ((k = ask_password_auto("Please enter passphrase for disk:", "drive-harddisk", until, &password)) < 0) {
 213                                         log_error("Failed to query password: %s", strerror(-k));
 214                                         goto finish;
 215                                 }
 216
 217                                 if (opt_verify) {
 218                                         char *password2 = NULL;
 219
 220                                         if ((k = ask_password_auto("Please enter passphrase for disk (verification):", "drive-harddisk", until, &password2)) < 0) {
 221                                                 log_error("Failed to query verification password: %s", strerror(-k));
 222                                                 goto finish;
 223                                         }
 224
 225                                         if (!streq(password, password2)) {
 226                                                 log_warning("Passwords did not match, retrying.");
 227                                                 free(password2);
 228                                                 continue;
 229                                         }
 230
 231                                         free(password2);
 232                                 }
 233
 234                                 if (strlen(password)+1 < opt_key_size) {
 235                                         char *c;
 236
 237                                         /* Pad password if necessary */
 238
 239                                         if (!(c = new(char, opt_key_size))) {
 240                                                 log_error("Out of memory.");
 241                                                 goto finish;
 242                                         }
 243
 244                                         strncpy(c, password, opt_key_size);
 245                                         free(password);
 246                                         password = c;
 247                                 }
 248                         }
 249
 250                         if (!opt_type || streq(opt_type, CRYPT_LUKS1))
 251                                 k = crypt_load(cd, CRYPT_LUKS1, NULL);
 252
 253                         if ((!opt_type && k < 0) || streq_ptr(opt_type, CRYPT_PLAIN)) {
 254                                 struct crypt_params_plain params;
 255
 256                                 zero(params);
 257                                 params.hash = hash;
 258
 259                                 /* In contrast to what the name
 260                                  * crypt_setup() might suggest this
 261                                  * doesn't actually format anything,
 262                                  * it just configures encryption
 263                                  * parameters when used for plain
 264                                  * mode. */
 265                                 k = crypt_format(cd, CRYPT_PLAIN,
 266                                                  cipher,
 267                                                  cipher_mode,
 268                                                  NULL,
 269                                                  NULL,
 270                                                  opt_key_size / 8,
 271                                                  &params);
 272
 273                                 pass_volume_key = streq(hash, "plain");
 274                         }
 275
 276                         if (k < 0) {
 277                                 log_error("Loading of cryptographic parameters failed: %s", strerror(-k));
 278                                 goto finish;
 279                         }
 280
 281                         log_info("Set cipher %s, mode %s, key size %i bits for device %s.",
 282                                  crypt_get_cipher(cd),
 283                                  crypt_get_cipher_mode(cd),
 284                                  crypt_get_volume_key_size(cd)*8,
 285                                  argv[3]);
 286
 287                         if (key_file)
 288                                 k = crypt_activate_by_keyfile(cd, argv[2], CRYPT_ANY_SLOT, key_file, opt_key_size, flags);
 289                         else if (pass_volume_key)
 290                                 k = crypt_activate_by_volume_key(cd, argv[2], password, opt_key_size, flags);
 291                         else
 292                                 k = crypt_activate_by_passphrase(cd, argv[2], CRYPT_ANY_SLOT, password, strlen(password), flags);
 293
 294                         if (k >= 0)
 295                                 break;
 296
 297                         if (k != -EPERM) {
 298                                 log_error("Failed to activate: %s", strerror(-k));
 299                                 goto finish;
 300                         }
 301
 302                         log_warning("Invalid passphrase.");
 303                 }
 304
 305                 if (try >= opt_tries) {
 306                         log_error("Too many attempts.");
 307                         r = EXIT_FAILURE;
 308                 }
 309
 310         } else if (streq(argv[1], "detach")) {
 311                 int k;
 312
 313                 if ((k = crypt_init_by_name(&cd, argv[2]))) {
 314                         log_error("crypt_init() failed: %s", strerror(-k));
 315                         goto finish;
 316                 }
 317
 318                 crypt_set_log_callback(cd, log_glue, NULL);
 319
 320                 if ((k = crypt_deactivate(cd, argv[2])) < 0) {
 321                         log_error("Failed to deactivate: %s", strerror(-k));
 322                         goto finish;
 323                 }
 324
 325         } else {
 326                 log_error("Unknown verb %s.", argv[1]);
 327                 goto finish;
 328         }
 329
 330         r = EXIT_SUCCESS;
 331
 332 finish:
 333
 334         if (cd)
 335                 crypt_free(cd);
 336
 337         free(opt_cipher);
 338         free(opt_cipher_mode);
 339         free(opt_hash);
 340
 341         free(password);
 342
 343         return r;
 344 }