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Diffstat (limited to 'src/systemd-cryptsetup/cryptsetup.c')
-rw-r--r--src/systemd-cryptsetup/cryptsetup.c753
1 files changed, 753 insertions, 0 deletions
diff --git a/src/systemd-cryptsetup/cryptsetup.c b/src/systemd-cryptsetup/cryptsetup.c
new file mode 100644
index 0000000000..9d8156697d
--- /dev/null
+++ b/src/systemd-cryptsetup/cryptsetup.c
@@ -0,0 +1,753 @@
+/***
+ This file is part of systemd.
+
+ Copyright 2010 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 <errno.h>
+#include <libcryptsetup.h>
+#include <mntent.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#include <systemd/sd-device.h>
+
+#include "alloc-util.h"
+#include "ask-password-api.h"
+#include "device-util.h"
+#include "escape.h"
+#include "fileio.h"
+#include "log.h"
+#include "mount-util.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "util.h"
+
+static const char *arg_type = NULL; /* CRYPT_LUKS1, CRYPT_TCRYPT or CRYPT_PLAIN */
+static char *arg_cipher = NULL;
+static unsigned arg_key_size = 0;
+static int arg_key_slot = CRYPT_ANY_SLOT;
+static unsigned arg_keyfile_size = 0;
+static unsigned arg_keyfile_offset = 0;
+static char *arg_hash = NULL;
+static char *arg_header = NULL;
+static unsigned arg_tries = 3;
+static bool arg_readonly = false;
+static bool arg_verify = false;
+static bool arg_discards = false;
+static bool arg_tcrypt_hidden = false;
+static bool arg_tcrypt_system = false;
+static char **arg_tcrypt_keyfiles = NULL;
+static uint64_t arg_offset = 0;
+static uint64_t arg_skip = 0;
+static usec_t arg_timeout = 0;
+
+/* Options Debian's crypttab knows we don't:
+
+ precheck=
+ check=
+ checkargs=
+ noearly=
+ loud=
+ keyscript=
+*/
+
+static int parse_one_option(const char *option) {
+ assert(option);
+
+ /* Handled outside of this tool */
+ if (STR_IN_SET(option, "noauto", "auto", "nofail", "fail"))
+ return 0;
+
+ if (startswith(option, "cipher=")) {
+ char *t;
+
+ t = strdup(option+7);
+ if (!t)
+ return log_oom();
+
+ free(arg_cipher);
+ arg_cipher = t;
+
+ } else if (startswith(option, "size=")) {
+
+ if (safe_atou(option+5, &arg_key_size) < 0) {
+ log_error("size= parse failure, ignoring.");
+ return 0;
+ }
+
+ if (arg_key_size % 8) {
+ log_error("size= not a multiple of 8, ignoring.");
+ return 0;
+ }
+
+ arg_key_size /= 8;
+
+ } else if (startswith(option, "key-slot=")) {
+
+ arg_type = CRYPT_LUKS1;
+ if (safe_atoi(option+9, &arg_key_slot) < 0) {
+ log_error("key-slot= parse failure, ignoring.");
+ return 0;
+ }
+
+ } else if (startswith(option, "tcrypt-keyfile=")) {
+
+ arg_type = CRYPT_TCRYPT;
+ if (path_is_absolute(option+15)) {
+ if (strv_extend(&arg_tcrypt_keyfiles, option + 15) < 0)
+ return log_oom();
+ } else
+ log_error("Key file path '%s' is not absolute. Ignoring.", option+15);
+
+ } else if (startswith(option, "keyfile-size=")) {
+
+ if (safe_atou(option+13, &arg_keyfile_size) < 0) {
+ log_error("keyfile-size= parse failure, ignoring.");
+ return 0;
+ }
+
+ } else if (startswith(option, "keyfile-offset=")) {
+
+ if (safe_atou(option+15, &arg_keyfile_offset) < 0) {
+ log_error("keyfile-offset= parse failure, ignoring.");
+ return 0;
+ }
+
+ } else if (startswith(option, "hash=")) {
+ char *t;
+
+ t = strdup(option+5);
+ if (!t)
+ return log_oom();
+
+ free(arg_hash);
+ arg_hash = t;
+
+ } else if (startswith(option, "header=")) {
+ arg_type = CRYPT_LUKS1;
+
+ if (!path_is_absolute(option+7)) {
+ log_error("Header path '%s' is not absolute, refusing.", option+7);
+ return -EINVAL;
+ }
+
+ if (arg_header) {
+ log_error("Duplicate header= options, refusing.");
+ return -EINVAL;
+ }
+
+ arg_header = strdup(option+7);
+ if (!arg_header)
+ return log_oom();
+
+ } else if (startswith(option, "tries=")) {
+
+ if (safe_atou(option+6, &arg_tries) < 0) {
+ log_error("tries= parse failure, ignoring.");
+ return 0;
+ }
+
+ } else if (STR_IN_SET(option, "readonly", "read-only"))
+ arg_readonly = true;
+ else if (streq(option, "verify"))
+ arg_verify = true;
+ else if (STR_IN_SET(option, "allow-discards", "discard"))
+ arg_discards = true;
+ else if (streq(option, "luks"))
+ arg_type = CRYPT_LUKS1;
+ else if (streq(option, "tcrypt"))
+ arg_type = CRYPT_TCRYPT;
+ else if (streq(option, "tcrypt-hidden")) {
+ arg_type = CRYPT_TCRYPT;
+ arg_tcrypt_hidden = true;
+ } else if (streq(option, "tcrypt-system")) {
+ arg_type = CRYPT_TCRYPT;
+ arg_tcrypt_system = true;
+ } else if (STR_IN_SET(option, "plain", "swap", "tmp"))
+ arg_type = CRYPT_PLAIN;
+ else if (startswith(option, "timeout=")) {
+
+ if (parse_sec(option+8, &arg_timeout) < 0) {
+ log_error("timeout= parse failure, ignoring.");
+ return 0;
+ }
+
+ } else if (startswith(option, "offset=")) {
+
+ if (safe_atou64(option+7, &arg_offset) < 0) {
+ log_error("offset= parse failure, refusing.");
+ return -EINVAL;
+ }
+
+ } else if (startswith(option, "skip=")) {
+
+ if (safe_atou64(option+5, &arg_skip) < 0) {
+ log_error("skip= parse failure, refusing.");
+ return -EINVAL;
+ }
+
+ } else if (!streq(option, "none"))
+ log_error("Encountered unknown /etc/crypttab option '%s', ignoring.", option);
+
+ return 0;
+}
+
+static int parse_options(const char *options) {
+ const char *word, *state;
+ size_t l;
+ int r;
+
+ assert(options);
+
+ FOREACH_WORD_SEPARATOR(word, l, options, ",", state) {
+ _cleanup_free_ char *o;
+
+ o = strndup(word, l);
+ if (!o)
+ return -ENOMEM;
+ r = parse_one_option(o);
+ if (r < 0)
+ return r;
+ }
+
+ /* sanity-check options */
+ if (arg_type != NULL && !streq(arg_type, CRYPT_PLAIN)) {
+ if (arg_offset)
+ log_warning("offset= ignored with type %s", arg_type);
+ if (arg_skip)
+ log_warning("skip= ignored with type %s", arg_type);
+ }
+
+ return 0;
+}
+
+static void log_glue(int level, const char *msg, void *usrptr) {
+ log_debug("%s", msg);
+}
+
+static int disk_major_minor(const char *path, char **ret) {
+ struct stat st;
+
+ assert(path);
+
+ if (stat(path, &st) < 0)
+ return -errno;
+
+ if (!S_ISBLK(st.st_mode))
+ return -EINVAL;
+
+ if (asprintf(ret, "/dev/block/%d:%d", major(st.st_rdev), minor(st.st_rdev)) < 0)
+ return -errno;
+
+ return 0;
+}
+
+static char* disk_description(const char *path) {
+
+ static const char name_fields[] =
+ "ID_PART_ENTRY_NAME\0"
+ "DM_NAME\0"
+ "ID_MODEL_FROM_DATABASE\0"
+ "ID_MODEL\0";
+
+ _cleanup_(sd_device_unrefp) sd_device *device = NULL;
+ struct stat st;
+ const char *i;
+ int r;
+
+ assert(path);
+
+ if (stat(path, &st) < 0)
+ return NULL;
+
+ if (!S_ISBLK(st.st_mode))
+ return NULL;
+
+ r = sd_device_new_from_devnum(&device, 'b', st.st_rdev);
+ if (r < 0)
+ return NULL;
+
+ NULSTR_FOREACH(i, name_fields) {
+ const char *name;
+
+ r = sd_device_get_property_value(device, i, &name);
+ if (r >= 0 && !isempty(name))
+ return strdup(name);
+ }
+
+ return NULL;
+}
+
+static char *disk_mount_point(const char *label) {
+ _cleanup_free_ char *device = NULL;
+ _cleanup_endmntent_ FILE *f = NULL;
+ struct mntent *m;
+
+ /* Yeah, we don't support native systemd unit files here for now */
+
+ if (asprintf(&device, "/dev/mapper/%s", label) < 0)
+ return NULL;
+
+ f = setmntent("/etc/fstab", "r");
+ if (!f)
+ return NULL;
+
+ while ((m = getmntent(f)))
+ if (path_equal(m->mnt_fsname, device))
+ return strdup(m->mnt_dir);
+
+ return NULL;
+}
+
+static int get_password(const char *vol, const char *src, usec_t until, bool accept_cached, char ***ret) {
+ _cleanup_free_ char *description = NULL, *name_buffer = NULL, *mount_point = NULL, *maj_min = NULL, *text = NULL, *escaped_name = NULL;
+ _cleanup_strv_free_erase_ char **passwords = NULL;
+ const char *name = NULL;
+ char **p, *id;
+ int r = 0;
+
+ assert(vol);
+ assert(src);
+ assert(ret);
+
+ description = disk_description(src);
+ mount_point = disk_mount_point(vol);
+
+ if (description && streq(vol, description))
+ /* If the description string is simply the
+ * volume name, then let's not show this
+ * twice */
+ description = mfree(description);
+
+ if (mount_point && description)
+ r = asprintf(&name_buffer, "%s (%s) on %s", description, vol, mount_point);
+ else if (mount_point)
+ r = asprintf(&name_buffer, "%s on %s", vol, mount_point);
+ else if (description)
+ r = asprintf(&name_buffer, "%s (%s)", description, vol);
+
+ if (r < 0)
+ return log_oom();
+
+ name = name_buffer ? name_buffer : vol;
+
+ if (asprintf(&text, "Please enter passphrase for disk %s!", name) < 0)
+ return log_oom();
+
+ if (src)
+ (void) disk_major_minor(src, &maj_min);
+
+ if (maj_min) {
+ escaped_name = maj_min;
+ maj_min = NULL;
+ } else
+ escaped_name = cescape(name);
+
+ if (!escaped_name)
+ return log_oom();
+
+ id = strjoina("cryptsetup:", escaped_name);
+
+ r = ask_password_auto(text, "drive-harddisk", id, "cryptsetup", until,
+ ASK_PASSWORD_PUSH_CACHE | (accept_cached*ASK_PASSWORD_ACCEPT_CACHED),
+ &passwords);
+ if (r < 0)
+ return log_error_errno(r, "Failed to query password: %m");
+
+ if (arg_verify) {
+ _cleanup_strv_free_erase_ char **passwords2 = NULL;
+
+ assert(strv_length(passwords) == 1);
+
+ if (asprintf(&text, "Please enter passphrase for disk %s! (verification)", name) < 0)
+ return log_oom();
+
+ id = strjoina("cryptsetup-verification:", escaped_name);
+
+ r = ask_password_auto(text, "drive-harddisk", id, "cryptsetup", until, ASK_PASSWORD_PUSH_CACHE, &passwords2);
+ if (r < 0)
+ return log_error_errno(r, "Failed to query verification password: %m");
+
+ assert(strv_length(passwords2) == 1);
+
+ if (!streq(passwords[0], passwords2[0])) {
+ log_warning("Passwords did not match, retrying.");
+ return -EAGAIN;
+ }
+ }
+
+ strv_uniq(passwords);
+
+ STRV_FOREACH(p, passwords) {
+ char *c;
+
+ if (strlen(*p)+1 >= arg_key_size)
+ continue;
+
+ /* Pad password if necessary */
+ c = new(char, arg_key_size);
+ if (!c)
+ return log_oom();
+
+ strncpy(c, *p, arg_key_size);
+ free(*p);
+ *p = c;
+ }
+
+ *ret = passwords;
+ passwords = NULL;
+
+ return 0;
+}
+
+static int attach_tcrypt(
+ struct crypt_device *cd,
+ const char *name,
+ const char *key_file,
+ char **passwords,
+ uint32_t flags) {
+
+ int r = 0;
+ _cleanup_free_ char *passphrase = NULL;
+ struct crypt_params_tcrypt params = {
+ .flags = CRYPT_TCRYPT_LEGACY_MODES,
+ .keyfiles = (const char **)arg_tcrypt_keyfiles,
+ .keyfiles_count = strv_length(arg_tcrypt_keyfiles)
+ };
+
+ assert(cd);
+ assert(name);
+ assert(key_file || (passwords && passwords[0]));
+
+ if (arg_tcrypt_hidden)
+ params.flags |= CRYPT_TCRYPT_HIDDEN_HEADER;
+
+ if (arg_tcrypt_system)
+ params.flags |= CRYPT_TCRYPT_SYSTEM_HEADER;
+
+ if (key_file) {
+ r = read_one_line_file(key_file, &passphrase);
+ if (r < 0) {
+ log_error_errno(r, "Failed to read password file '%s': %m", key_file);
+ return -EAGAIN;
+ }
+
+ params.passphrase = passphrase;
+ } else
+ params.passphrase = passwords[0];
+ params.passphrase_size = strlen(params.passphrase);
+
+ r = crypt_load(cd, CRYPT_TCRYPT, &params);
+ if (r < 0) {
+ if (key_file && r == -EPERM) {
+ log_error("Failed to activate using password file '%s'.", key_file);
+ return -EAGAIN;
+ }
+ return r;
+ }
+
+ return crypt_activate_by_volume_key(cd, name, NULL, 0, flags);
+}
+
+static int attach_luks_or_plain(struct crypt_device *cd,
+ const char *name,
+ const char *key_file,
+ const char *data_device,
+ char **passwords,
+ uint32_t flags) {
+ int r = 0;
+ bool pass_volume_key = false;
+
+ assert(cd);
+ assert(name);
+ assert(key_file || passwords);
+
+ if (!arg_type || streq(arg_type, CRYPT_LUKS1)) {
+ r = crypt_load(cd, CRYPT_LUKS1, NULL);
+ if (r < 0) {
+ log_error("crypt_load() failed on device %s.\n", crypt_get_device_name(cd));
+ return r;
+ }
+
+ if (data_device)
+ r = crypt_set_data_device(cd, data_device);
+ }
+
+ if ((!arg_type && r < 0) || streq_ptr(arg_type, CRYPT_PLAIN)) {
+ struct crypt_params_plain params = {
+ .offset = arg_offset,
+ .skip = arg_skip,
+ };
+ const char *cipher, *cipher_mode;
+ _cleanup_free_ char *truncated_cipher = NULL;
+
+ if (arg_hash) {
+ /* plain isn't a real hash type. it just means "use no hash" */
+ if (!streq(arg_hash, "plain"))
+ params.hash = arg_hash;
+ } else if (!key_file)
+ /* for CRYPT_PLAIN, the behaviour of cryptsetup
+ * package is to not hash when a key file is provided */
+ params.hash = "ripemd160";
+
+ if (arg_cipher) {
+ size_t l;
+
+ l = strcspn(arg_cipher, "-");
+ truncated_cipher = strndup(arg_cipher, l);
+ if (!truncated_cipher)
+ return log_oom();
+
+ cipher = truncated_cipher;
+ cipher_mode = arg_cipher[l] ? arg_cipher+l+1 : "plain";
+ } else {
+ cipher = "aes";
+ cipher_mode = "cbc-essiv:sha256";
+ }
+
+ /* for CRYPT_PLAIN limit reads
+ * from keyfile to key length, and
+ * ignore keyfile-size */
+ arg_keyfile_size = arg_key_size;
+
+ /* In contrast to what the name
+ * crypt_setup() might suggest this
+ * doesn't actually format anything,
+ * it just configures encryption
+ * parameters when used for plain
+ * mode. */
+ r = crypt_format(cd, CRYPT_PLAIN, cipher, cipher_mode, NULL, NULL, arg_keyfile_size, &params);
+
+ /* hash == NULL implies the user passed "plain" */
+ pass_volume_key = (params.hash == NULL);
+ }
+
+ if (r < 0)
+ return log_error_errno(r, "Loading of cryptographic parameters failed: %m");
+
+ log_info("Set cipher %s, mode %s, key size %i bits for device %s.",
+ crypt_get_cipher(cd),
+ crypt_get_cipher_mode(cd),
+ crypt_get_volume_key_size(cd)*8,
+ crypt_get_device_name(cd));
+
+ if (key_file) {
+ r = crypt_activate_by_keyfile_offset(cd, name, arg_key_slot, key_file, arg_keyfile_size, arg_keyfile_offset, flags);
+ if (r < 0) {
+ log_error_errno(r, "Failed to activate with key file '%s': %m", key_file);
+ return -EAGAIN;
+ }
+ } else {
+ char **p;
+
+ STRV_FOREACH(p, passwords) {
+ if (pass_volume_key)
+ r = crypt_activate_by_volume_key(cd, name, *p, arg_key_size, flags);
+ else
+ r = crypt_activate_by_passphrase(cd, name, arg_key_slot, *p, strlen(*p), flags);
+
+ if (r >= 0)
+ break;
+ }
+ }
+
+ return r;
+}
+
+static int help(void) {
+
+ printf("%s attach VOLUME SOURCEDEVICE [PASSWORD] [OPTIONS]\n"
+ "%s detach VOLUME\n\n"
+ "Attaches or detaches an encrypted block device.\n",
+ program_invocation_short_name,
+ program_invocation_short_name);
+
+ return 0;
+}
+
+int main(int argc, char *argv[]) {
+ int r = EXIT_FAILURE;
+ struct crypt_device *cd = NULL;
+
+ if (argc <= 1) {
+ help();
+ return EXIT_SUCCESS;
+ }
+
+ if (argc < 3) {
+ log_error("This program requires at least two arguments.");
+ return EXIT_FAILURE;
+ }
+
+ log_set_target(LOG_TARGET_AUTO);
+ log_parse_environment();
+ log_open();
+
+ umask(0022);
+
+ if (streq(argv[1], "attach")) {
+ uint32_t flags = 0;
+ int k;
+ unsigned tries;
+ usec_t until;
+ crypt_status_info status;
+ const char *key_file = NULL;
+
+ /* Arguments: systemd-cryptsetup attach VOLUME SOURCE-DEVICE [PASSWORD] [OPTIONS] */
+
+ if (argc < 4) {
+ log_error("attach requires at least two arguments.");
+ goto finish;
+ }
+
+ if (argc >= 5 &&
+ argv[4][0] &&
+ !streq(argv[4], "-") &&
+ !streq(argv[4], "none")) {
+
+ if (!path_is_absolute(argv[4]))
+ log_error("Password file path '%s' is not absolute. Ignoring.", argv[4]);
+ else
+ key_file = argv[4];
+ }
+
+ if (argc >= 6 && argv[5][0] && !streq(argv[5], "-")) {
+ if (parse_options(argv[5]) < 0)
+ goto finish;
+ }
+
+ /* A delicious drop of snake oil */
+ mlockall(MCL_FUTURE);
+
+ if (arg_header) {
+ log_debug("LUKS header: %s", arg_header);
+ k = crypt_init(&cd, arg_header);
+ } else
+ k = crypt_init(&cd, argv[3]);
+ if (k) {
+ log_error_errno(k, "crypt_init() failed: %m");
+ goto finish;
+ }
+
+ crypt_set_log_callback(cd, log_glue, NULL);
+
+ status = crypt_status(cd, argv[2]);
+ if (status == CRYPT_ACTIVE || status == CRYPT_BUSY) {
+ log_info("Volume %s already active.", argv[2]);
+ r = EXIT_SUCCESS;
+ goto finish;
+ }
+
+ if (arg_readonly)
+ flags |= CRYPT_ACTIVATE_READONLY;
+
+ if (arg_discards)
+ flags |= CRYPT_ACTIVATE_ALLOW_DISCARDS;
+
+ if (arg_timeout > 0)
+ until = now(CLOCK_MONOTONIC) + arg_timeout;
+ else
+ until = 0;
+
+ arg_key_size = (arg_key_size > 0 ? arg_key_size : (256 / 8));
+
+ if (key_file) {
+ struct stat st;
+
+ /* Ideally we'd do this on the open fd, but since this is just a
+ * warning it's OK to do this in two steps. */
+ if (stat(key_file, &st) >= 0 && S_ISREG(st.st_mode) && (st.st_mode & 0005))
+ log_warning("Key file %s is world-readable. This is not a good idea!", key_file);
+ }
+
+ for (tries = 0; arg_tries == 0 || tries < arg_tries; tries++) {
+ _cleanup_strv_free_erase_ char **passwords = NULL;
+
+ if (!key_file) {
+ k = get_password(argv[2], argv[3], until, tries == 0 && !arg_verify, &passwords);
+ if (k == -EAGAIN)
+ continue;
+ else if (k < 0)
+ goto finish;
+ }
+
+ if (streq_ptr(arg_type, CRYPT_TCRYPT))
+ k = attach_tcrypt(cd, argv[2], key_file, passwords, flags);
+ else
+ k = attach_luks_or_plain(cd,
+ argv[2],
+ key_file,
+ arg_header ? argv[3] : NULL,
+ passwords,
+ flags);
+ if (k >= 0)
+ break;
+ else if (k == -EAGAIN) {
+ key_file = NULL;
+ continue;
+ } else if (k != -EPERM) {
+ log_error_errno(k, "Failed to activate: %m");
+ goto finish;
+ }
+
+ log_warning("Invalid passphrase.");
+ }
+
+ if (arg_tries != 0 && tries >= arg_tries) {
+ log_error("Too many attempts; giving up.");
+ r = EXIT_FAILURE;
+ goto finish;
+ }
+
+ } else if (streq(argv[1], "detach")) {
+ int k;
+
+ k = crypt_init_by_name(&cd, argv[2]);
+ if (k) {
+ log_error_errno(k, "crypt_init() failed: %m");
+ goto finish;
+ }
+
+ crypt_set_log_callback(cd, log_glue, NULL);
+
+ k = crypt_deactivate(cd, argv[2]);
+ if (k < 0) {
+ log_error_errno(k, "Failed to deactivate: %m");
+ goto finish;
+ }
+
+ } else {
+ log_error("Unknown verb %s.", argv[1]);
+ goto finish;
+ }
+
+ r = EXIT_SUCCESS;
+
+finish:
+
+ if (cd)
+ crypt_free(cd);
+
+ free(arg_cipher);
+ free(arg_hash);
+ free(arg_header);
+ strv_free(arg_tcrypt_keyfiles);
+
+ return r;
+}