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Diffstat (limited to 'src/systemd-cryptsetup/cryptsetup-generator.c')
-rw-r--r--src/systemd-cryptsetup/cryptsetup-generator.c509
1 files changed, 509 insertions, 0 deletions
diff --git a/src/systemd-cryptsetup/cryptsetup-generator.c b/src/systemd-cryptsetup/cryptsetup-generator.c
new file mode 100644
index 0000000000..8ac5ab730a
--- /dev/null
+++ b/src/systemd-cryptsetup/cryptsetup-generator.c
@@ -0,0 +1,509 @@
+/***
+ 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 "alloc-util.h"
+#include "dropin.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "fstab-util.h"
+#include "generator.h"
+#include "hashmap.h"
+#include "log.h"
+#include "mkdir.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "proc-cmdline.h"
+#include "string-util.h"
+#include "strv.h"
+#include "unit-name.h"
+#include "util.h"
+
+typedef struct crypto_device {
+ char *uuid;
+ char *keyfile;
+ char *name;
+ char *options;
+ bool create;
+} crypto_device;
+
+static const char *arg_dest = "/tmp";
+static bool arg_enabled = true;
+static bool arg_read_crypttab = true;
+static bool arg_whitelist = false;
+static Hashmap *arg_disks = NULL;
+static char *arg_default_options = NULL;
+static char *arg_default_keyfile = NULL;
+
+static int create_disk(
+ const char *name,
+ const char *device,
+ const char *password,
+ const char *options) {
+
+ _cleanup_free_ char *p = NULL, *n = NULL, *d = NULL, *u = NULL, *to = NULL, *e = NULL,
+ *filtered = NULL;
+ _cleanup_fclose_ FILE *f = NULL;
+ bool noauto, nofail, tmp, swap;
+ char *from;
+ int r;
+
+ assert(name);
+ assert(device);
+
+ noauto = fstab_test_yes_no_option(options, "noauto\0" "auto\0");
+ nofail = fstab_test_yes_no_option(options, "nofail\0" "fail\0");
+ tmp = fstab_test_option(options, "tmp\0");
+ swap = fstab_test_option(options, "swap\0");
+
+ if (tmp && swap) {
+ log_error("Device '%s' cannot be both 'tmp' and 'swap'. Ignoring.", name);
+ return -EINVAL;
+ }
+
+ e = unit_name_escape(name);
+ if (!e)
+ return log_oom();
+
+ r = unit_name_build("systemd-cryptsetup", e, ".service", &n);
+ if (r < 0)
+ return log_error_errno(r, "Failed to generate unit name: %m");
+
+ p = strjoin(arg_dest, "/", n, NULL);
+ if (!p)
+ return log_oom();
+
+ u = fstab_node_to_udev_node(device);
+ if (!u)
+ return log_oom();
+
+ r = unit_name_from_path(u, ".device", &d);
+ if (r < 0)
+ return log_error_errno(r, "Failed to generate unit name: %m");
+
+ f = fopen(p, "wxe");
+ if (!f)
+ return log_error_errno(errno, "Failed to create unit file %s: %m", p);
+
+ fputs(
+ "# Automatically generated by systemd-cryptsetup-generator\n\n"
+ "[Unit]\n"
+ "Description=Cryptography Setup for %I\n"
+ "Documentation=man:crypttab(5) man:systemd-cryptsetup-generator(8) man:systemd-cryptsetup@.service(8)\n"
+ "SourcePath=/etc/crypttab\n"
+ "DefaultDependencies=no\n"
+ "Conflicts=umount.target\n"
+ "BindsTo=dev-mapper-%i.device\n"
+ "IgnoreOnIsolate=true\n"
+ "After=cryptsetup-pre.target\n",
+ f);
+
+ if (!nofail)
+ fprintf(f,
+ "Before=cryptsetup.target\n");
+
+ if (password) {
+ if (STR_IN_SET(password, "/dev/urandom", "/dev/random", "/dev/hw_random"))
+ fputs("After=systemd-random-seed.service\n", f);
+ else if (!streq(password, "-") && !streq(password, "none")) {
+ _cleanup_free_ char *uu;
+
+ uu = fstab_node_to_udev_node(password);
+ if (!uu)
+ return log_oom();
+
+ if (!path_equal(uu, "/dev/null")) {
+
+ if (is_device_path(uu)) {
+ _cleanup_free_ char *dd = NULL;
+
+ r = unit_name_from_path(uu, ".device", &dd);
+ if (r < 0)
+ return log_error_errno(r, "Failed to generate unit name: %m");
+
+ fprintf(f, "After=%1$s\nRequires=%1$s\n", dd);
+ } else
+ fprintf(f, "RequiresMountsFor=%s\n", password);
+ }
+ }
+ }
+
+ if (is_device_path(u))
+ fprintf(f,
+ "BindsTo=%s\n"
+ "After=%s\n"
+ "Before=umount.target\n",
+ d, d);
+ else
+ fprintf(f,
+ "RequiresMountsFor=%s\n",
+ u);
+
+ r = generator_write_timeouts(arg_dest, device, name, options, &filtered);
+ if (r < 0)
+ return r;
+
+ fprintf(f,
+ "\n[Service]\n"
+ "Type=oneshot\n"
+ "RemainAfterExit=yes\n"
+ "TimeoutSec=0\n" /* the binary handles timeouts anyway */
+ "ExecStart=" SYSTEMD_CRYPTSETUP_PATH " attach '%s' '%s' '%s' '%s'\n"
+ "ExecStop=" SYSTEMD_CRYPTSETUP_PATH " detach '%s'\n",
+ name, u, strempty(password), strempty(filtered),
+ name);
+
+ if (tmp)
+ fprintf(f,
+ "ExecStartPost=/sbin/mke2fs '/dev/mapper/%s'\n",
+ name);
+
+ if (swap)
+ fprintf(f,
+ "ExecStartPost=/sbin/mkswap '/dev/mapper/%s'\n",
+ name);
+
+ r = fflush_and_check(f);
+ if (r < 0)
+ return log_error_errno(r, "Failed to write file %s: %m", p);
+
+ from = strjoina("../", n);
+
+ if (!noauto) {
+
+ to = strjoin(arg_dest, "/", d, ".wants/", n, NULL);
+ if (!to)
+ return log_oom();
+
+ mkdir_parents_label(to, 0755);
+ if (symlink(from, to) < 0)
+ return log_error_errno(errno, "Failed to create symlink %s: %m", to);
+
+ free(to);
+ if (!nofail)
+ to = strjoin(arg_dest, "/cryptsetup.target.requires/", n, NULL);
+ else
+ to = strjoin(arg_dest, "/cryptsetup.target.wants/", n, NULL);
+ if (!to)
+ return log_oom();
+
+ mkdir_parents_label(to, 0755);
+ if (symlink(from, to) < 0)
+ return log_error_errno(errno, "Failed to create symlink %s: %m", to);
+ }
+
+ free(to);
+ to = strjoin(arg_dest, "/dev-mapper-", e, ".device.requires/", n, NULL);
+ if (!to)
+ return log_oom();
+
+ mkdir_parents_label(to, 0755);
+ if (symlink(from, to) < 0)
+ return log_error_errno(errno, "Failed to create symlink %s: %m", to);
+
+ if (!noauto && !nofail) {
+ _cleanup_free_ char *dmname;
+ dmname = strjoin("dev-mapper-", e, ".device", NULL);
+ if (!dmname)
+ return log_oom();
+
+ r = write_drop_in(arg_dest, dmname, 90, "device-timeout",
+ "# Automatically generated by systemd-cryptsetup-generator \n\n"
+ "[Unit]\nJobTimeoutSec=0");
+ if (r < 0)
+ return log_error_errno(r, "Failed to write device drop-in: %m");
+ }
+
+ return 0;
+}
+
+static void free_arg_disks(void) {
+ crypto_device *d;
+
+ while ((d = hashmap_steal_first(arg_disks))) {
+ free(d->uuid);
+ free(d->keyfile);
+ free(d->name);
+ free(d->options);
+ free(d);
+ }
+
+ hashmap_free(arg_disks);
+}
+
+static crypto_device *get_crypto_device(const char *uuid) {
+ int r;
+ crypto_device *d;
+
+ assert(uuid);
+
+ d = hashmap_get(arg_disks, uuid);
+ if (!d) {
+ d = new0(struct crypto_device, 1);
+ if (!d)
+ return NULL;
+
+ d->create = false;
+ d->keyfile = d->options = d->name = NULL;
+
+ d->uuid = strdup(uuid);
+ if (!d->uuid) {
+ free(d);
+ return NULL;
+ }
+
+ r = hashmap_put(arg_disks, d->uuid, d);
+ if (r < 0) {
+ free(d->uuid);
+ free(d);
+ return NULL;
+ }
+ }
+
+ return d;
+}
+
+static int parse_proc_cmdline_item(const char *key, const char *value) {
+ int r;
+ crypto_device *d;
+ _cleanup_free_ char *uuid = NULL, *uuid_value = NULL;
+
+ if (STR_IN_SET(key, "luks", "rd.luks") && value) {
+
+ r = parse_boolean(value);
+ if (r < 0)
+ log_warning("Failed to parse luks switch %s. Ignoring.", value);
+ else
+ arg_enabled = r;
+
+ } else if (STR_IN_SET(key, "luks.crypttab", "rd.luks.crypttab") && value) {
+
+ r = parse_boolean(value);
+ if (r < 0)
+ log_warning("Failed to parse luks crypttab switch %s. Ignoring.", value);
+ else
+ arg_read_crypttab = r;
+
+ } else if (STR_IN_SET(key, "luks.uuid", "rd.luks.uuid") && value) {
+
+ d = get_crypto_device(startswith(value, "luks-") ? value+5 : value);
+ if (!d)
+ return log_oom();
+
+ d->create = arg_whitelist = true;
+
+ } else if (STR_IN_SET(key, "luks.options", "rd.luks.options") && value) {
+
+ r = sscanf(value, "%m[0-9a-fA-F-]=%ms", &uuid, &uuid_value);
+ if (r == 2) {
+ d = get_crypto_device(uuid);
+ if (!d)
+ return log_oom();
+
+ free(d->options);
+ d->options = uuid_value;
+ uuid_value = NULL;
+ } else if (free_and_strdup(&arg_default_options, value) < 0)
+ return log_oom();
+
+ } else if (STR_IN_SET(key, "luks.key", "rd.luks.key") && value) {
+
+ r = sscanf(value, "%m[0-9a-fA-F-]=%ms", &uuid, &uuid_value);
+ if (r == 2) {
+ d = get_crypto_device(uuid);
+ if (!d)
+ return log_oom();
+
+ free(d->keyfile);
+ d->keyfile = uuid_value;
+ uuid_value = NULL;
+ } else if (free_and_strdup(&arg_default_keyfile, value) < 0)
+ return log_oom();
+
+ } else if (STR_IN_SET(key, "luks.name", "rd.luks.name") && value) {
+
+ r = sscanf(value, "%m[0-9a-fA-F-]=%ms", &uuid, &uuid_value);
+ if (r == 2) {
+ d = get_crypto_device(uuid);
+ if (!d)
+ return log_oom();
+
+ d->create = arg_whitelist = true;
+
+ free(d->name);
+ d->name = uuid_value;
+ uuid_value = NULL;
+ } else
+ log_warning("Failed to parse luks name switch %s. Ignoring.", value);
+
+ }
+
+ return 0;
+}
+
+static int add_crypttab_devices(void) {
+ struct stat st;
+ unsigned crypttab_line = 0;
+ _cleanup_fclose_ FILE *f = NULL;
+
+ if (!arg_read_crypttab)
+ return 0;
+
+ f = fopen("/etc/crypttab", "re");
+ if (!f) {
+ if (errno != ENOENT)
+ log_error_errno(errno, "Failed to open /etc/crypttab: %m");
+ return 0;
+ }
+
+ if (fstat(fileno(f), &st) < 0) {
+ log_error_errno(errno, "Failed to stat /etc/crypttab: %m");
+ return 0;
+ }
+
+ for (;;) {
+ int r, k;
+ char line[LINE_MAX], *l, *uuid;
+ crypto_device *d = NULL;
+ _cleanup_free_ char *name = NULL, *device = NULL, *keyfile = NULL, *options = NULL;
+
+ if (!fgets(line, sizeof(line), f))
+ break;
+
+ crypttab_line++;
+
+ l = strstrip(line);
+ if (*l == '#' || *l == 0)
+ continue;
+
+ k = sscanf(l, "%ms %ms %ms %ms", &name, &device, &keyfile, &options);
+ if (k < 2 || k > 4) {
+ log_error("Failed to parse /etc/crypttab:%u, ignoring.", crypttab_line);
+ continue;
+ }
+
+ uuid = startswith(device, "UUID=");
+ if (!uuid)
+ uuid = path_startswith(device, "/dev/disk/by-uuid/");
+ if (!uuid)
+ uuid = startswith(name, "luks-");
+ if (uuid)
+ d = hashmap_get(arg_disks, uuid);
+
+ if (arg_whitelist && !d) {
+ log_info("Not creating device '%s' because it was not specified on the kernel command line.", name);
+ continue;
+ }
+
+ r = create_disk(name, device, keyfile, (d && d->options) ? d->options : options);
+ if (r < 0)
+ return r;
+
+ if (d)
+ d->create = false;
+ }
+
+ return 0;
+}
+
+static int add_proc_cmdline_devices(void) {
+ int r;
+ Iterator i;
+ crypto_device *d;
+
+ HASHMAP_FOREACH(d, arg_disks, i) {
+ const char *options;
+ _cleanup_free_ char *device = NULL;
+
+ if (!d->create)
+ continue;
+
+ if (!d->name) {
+ d->name = strappend("luks-", d->uuid);
+ if (!d->name)
+ return log_oom();
+ }
+
+ device = strappend("UUID=", d->uuid);
+ if (!device)
+ return log_oom();
+
+ if (d->options)
+ options = d->options;
+ else if (arg_default_options)
+ options = arg_default_options;
+ else
+ options = "timeout=0";
+
+ r = create_disk(d->name, device, d->keyfile ?: arg_default_keyfile, options);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+int main(int argc, char *argv[]) {
+ int r = EXIT_FAILURE;
+
+ if (argc > 1 && argc != 4) {
+ log_error("This program takes three or no arguments.");
+ return EXIT_FAILURE;
+ }
+
+ if (argc > 1)
+ arg_dest = argv[1];
+
+ log_set_target(LOG_TARGET_SAFE);
+ log_parse_environment();
+ log_open();
+
+ umask(0022);
+
+ arg_disks = hashmap_new(&string_hash_ops);
+ if (!arg_disks)
+ goto cleanup;
+
+ r = parse_proc_cmdline(parse_proc_cmdline_item);
+ if (r < 0) {
+ log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
+ r = EXIT_FAILURE;
+ }
+
+ if (!arg_enabled) {
+ r = EXIT_SUCCESS;
+ goto cleanup;
+ }
+
+ if (add_crypttab_devices() < 0)
+ goto cleanup;
+
+ if (add_proc_cmdline_devices() < 0)
+ goto cleanup;
+
+ r = EXIT_SUCCESS;
+
+cleanup:
+ free_arg_disks();
+ free(arg_default_options);
+ free(arg_default_keyfile);
+
+ return r;
+}