#include <string.h>

#include <errno.h>

#include <sys/mman.h>

#include <mntent.h>

#include <libcryptsetup.h>

#include <libudev.h>

#include "log.h"

#include "util.h"

#include "strv.h"

#include "ask-password-api.h"

#include "def.h"

static const char *opt_type = NULL; /* LUKS1 or PLAIN */

static char *opt_cipher = NULL;

static unsigned opt_key_size = 0;

static char *opt_hash = NULL;

static unsigned opt_tries = 0;

static bool opt_readonly = false;

static bool opt_verify = false;

static usec_t opt_timeout = DEFAULT_TIMEOUT_USEC;

static int parse_one_option(const char *option) {

assert(option);

/* Handled outside of this tool */

if (streq(option, "noauto"))

return 0;

if (startswith(option, "cipher=")) {

char *t;

if (!(t = strdup(option+7)))

return -ENOMEM;

free(opt_cipher);

opt_cipher = t;

} else if (startswith(option, "size=")) {

if (safe_atou(option+5, &opt_key_size) < 0) {

log_error("size= parse failure, ignoring.");

return 0;

}

} else if (startswith(option, "hash=")) {

char *t;

if (!(t = strdup(option+5)))

return -ENOMEM;

free(opt_hash);

opt_hash = t;

} else if (startswith(option, "tries=")) {

if (safe_atou(option+6, &opt_tries) < 0) {

log_error("tries= parse failure, ignoring.");

return 0;

}

} else if (streq(option, "readonly"))

opt_readonly = true;

else if (streq(option, "verify"))

opt_verify = true;

else if (streq(option, "luks"))

opt_type = CRYPT_LUKS1;

else if (streq(option, "plain") ||

streq(option, "swap") ||

streq(option, "tmp"))

opt_type = CRYPT_PLAIN;

else if (startswith(option, "timeout=")) {

if (parse_usec(option+8, &opt_timeout) < 0) {

log_error("timeout= parse failure, ignoring.");

return 0;

}

} else if (!streq(option, "none"))

log_error("Encountered unknown /etc/crypttab option '%s', ignoring.", option);

return 0;

}

static int parse_options(const char *options) {

char *state;

char *w;

size_t l;

assert(options);

FOREACH_WORD_SEPARATOR(w, l, options, ",", state) {

char *o;

int r;

if (!(o = strndup(w, l)))

return -ENOMEM;

r = parse_one_option(o);

free(o);

if (r < 0)

return r;

}

return 0;

}

static void log_glue(int level, const char *msg, void *usrptr) {

log_debug("%s", msg);

}

static char *disk_description(const char *path) {

struct udev *udev = NULL;

struct udev_device *device = NULL;

struct stat st;

char *description = NULL;

const char *model;

assert(path);

if (stat(path, &st) < 0)

return NULL;

if (!S_ISBLK(st.st_mode))

return NULL;

if (!(udev = udev_new()))

return NULL;

if (!(device = udev_device_new_from_devnum(udev, 'b', st.st_rdev)))

goto finish;

if ((model = udev_device_get_property_value(device, "ID_MODEL_FROM_DATABASE")) ||

(model = udev_device_get_property_value(device, "ID_MODEL")) ||

(model = udev_device_get_property_value(device, "DM_NAME")))

description = strdup(model);

finish:

if (device)

udev_device_unref(device);

if (udev)

udev_unref(udev);

return description;

}

static char *disk_mount_point(const char *label) {

char *mp = NULL, *device = NULL;

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)

goto finish;

if (!(f = setmntent("/etc/fstab", "r")))

goto finish;

while ((m = getmntent(f)))

if (path_equal(m->mnt_fsname, device)) {

mp = strdup(m->mnt_dir);

break;

}

finish:

if (f)

endmntent(f);

free(device);

return mp;

}

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;

char **passwords = NULL, *truncated_cipher = NULL;

const char *cipher = NULL, *cipher_mode = NULL, *hash = NULL, *name = NULL;

char *description = NULL, *name_buffer = NULL, *mount_point = NULL;

unsigned keyfile_size = 0;

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 try;

const char *key_file = NULL;

usec_t until;

crypt_status_info status;

/* 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], "-"))

parse_options(argv[5]);

/* A delicious drop of snake oil */

mlockall(MCL_FUTURE);

description = disk_description(argv[3]);

mount_point = disk_mount_point(argv[2]);

if (description && streq(argv[2], description)) {

/* If the description string is simply the

free(description);

description = NULL;

}

if (mount_point && description)

asprintf(&name_buffer, "%s (%s) on %s", description, argv[2], mount_point);

else if (mount_point)

asprintf(&name_buffer, "%s on %s", argv[2], mount_point);

else if (description)

asprintf(&name_buffer, "%s (%s)", description, argv[2]);

name = name_buffer ? name_buffer : argv[2];

if ((k = crypt_init(&cd, argv[3]))) {

log_error("crypt_init() failed: %s", strerror(-k));

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 (opt_readonly)

flags |= CRYPT_ACTIVATE_READONLY;

if (opt_timeout > 0)

until = now(CLOCK_MONOTONIC) + opt_timeout;

else

until = 0;

opt_tries = opt_tries > 0 ? opt_tries : 3;

opt_key_size = (opt_key_size > 0 ? opt_key_size : 256);

hash = opt_hash ? opt_hash : "ripemd160";

if (opt_cipher) {

size_t l;

l = strcspn(opt_cipher, "-");

if (!(truncated_cipher = strndup(opt_cipher, l))) {

log_error("Out of memory");

goto finish;

}

cipher = truncated_cipher;

cipher_mode = opt_cipher[l] ? opt_cipher+l+1 : "plain";

} else {

cipher = "aes";

cipher_mode = "cbc-essiv:sha256";

}

for (try = 0; try < opt_tries; try++) {

bool pass_volume_key = false;

strv_free(passwords);

passwords = NULL;

if (!key_file) {

char *text;

char **p;

if (asprintf(&text, "Please enter passphrase for disk %s!", name) < 0) {

log_error("Out of memory");

goto finish;

}

k = ask_password_auto(text, "drive-harddisk", until, try == 0 && !opt_verify, &passwords);

free(text);

if (k < 0) {

log_error("Failed to query password: %s", strerror(-k));

goto finish;

}

if (opt_verify) {

char **passwords2 = NULL;

assert(strv_length(passwords) == 1);

if (asprintf(&text, "Please enter passphrase for disk %s! (verification)", name) < 0) {

log_error("Out of memory");

goto finish;

}

k = ask_password_auto(text, "drive-harddisk", until, false, &passwords2);

free(text);

if (k < 0) {

log_error("Failed to query verification password: %s", strerror(-k));

goto finish;

}

assert(strv_length(passwords2) == 1);

if (!streq(passwords[0], passwords2[0])) {

log_warning("Passwords did not match, retrying.");

strv_free(passwords2);

continue;

}

strv_free(passwords2);

}

strv_uniq(passwords);

STRV_FOREACH(p, passwords) {

char *c;

if (strlen(*p)+1 >= opt_key_size)

continue;

/* Pad password if necessary */

if (!(c = new(char, opt_key_size))) {

log_error("Out of memory.");

goto finish;

}

strncpy(c, *p, opt_key_size);

free(*p);

*p = c;

}

}

k = 0;

if (!opt_type || streq(opt_type, CRYPT_LUKS1))

k = crypt_load(cd, CRYPT_LUKS1, NULL);

if ((!opt_type && k < 0) || streq_ptr(opt_type, CRYPT_PLAIN)) {

struct crypt_params_plain params;

zero(params);

params.hash = hash;

/* In contrast to what the name

k = crypt_format(cd, CRYPT_PLAIN,

cipher,

cipher_mode,

NULL,

NULL,

opt_key_size / 8,

&params);

pass_volume_key = streq(hash, "plain");

/* for CRYPT_PLAIN limit reads

keyfile_size = opt_key_size / 8;

}

if (k < 0) {

log_error("Loading of cryptographic parameters failed: %s", strerror(-k));

goto finish;

}

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,

argv[3]);

if (key_file)

k = crypt_activate_by_keyfile(cd, argv[2], CRYPT_ANY_SLOT, key_file, keyfile_size, flags);

else {

char **p;

STRV_FOREACH(p, passwords) {

if (pass_volume_key)

k = crypt_activate_by_volume_key(cd, argv[2], *p, opt_key_size, flags);

else

k = crypt_activate_by_passphrase(cd, argv[2], CRYPT_ANY_SLOT, *p, strlen(*p), flags);

if (k >= 0)

break;

}

}

if (k >= 0)

break;

if (k != -EPERM) {

log_error("Failed to activate: %s", strerror(-k));

goto finish;

}

log_warning("Invalid passphrase.");

}

if (try >= opt_tries) {

log_error("Too many attempts.");

r = EXIT_FAILURE;

goto finish;

}

} else if (streq(argv[1], "detach")) {

int k;

if ((k = crypt_init_by_name(&cd, argv[2]))) {

log_error("crypt_init() failed: %s", strerror(-k));

goto finish;

}

crypt_set_log_callback(cd, log_glue, NULL);

if ((k = crypt_deactivate(cd, argv[2])) < 0) {

log_error("Failed to deactivate: %s", strerror(-k));

goto finish;

}

} else {

log_error("Unknown verb %s.", argv[1]);

goto finish;

}

r = EXIT_SUCCESS;

finish:

if (cd)

crypt_free(cd);

free(opt_cipher);

free(opt_hash);

free(truncated_cipher);

strv_free(passwords);

free(description);

free(mount_point);

free(name_buffer);

return r;

}