chiark / gitweb /
cryptsetup-generator: Split main() into more functions and use hasmaps
[elogind.git] / src / cryptsetup / cryptsetup-generator.c
index 4056d1ddd205bf23e88b0335e305f21b32ca453c..c1581ef9c8a7be55a18044eed0c2356803780631 100644 (file)
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
-#include <string.h>
 #include <errno.h>
+#include <string.h>
 #include <unistd.h>
 
+#include "dropin.h"
+#include "fileio.h"
+#include "generator.h"
+#include "hashmap.h"
 #include "log.h"
-#include "util.h"
-#include "unit-name.h"
 #include "mkdir.h"
-#include "virt.h"
+#include "path-util.h"
 #include "strv.h"
+#include "unit-name.h"
+#include "util.h"
+
+typedef struct crypto_device {
+        char *uuid;
+        char *options;
+        bool create;
+} crypto_device;
 
 static const char *arg_dest = "/tmp";
 static bool arg_enabled = true;
 static bool arg_read_crypttab = true;
-static char **arg_proc_cmdline_disks = NULL;
+static bool arg_whitelist = false;
+static Hashmap *arg_disks = NULL;
+static char *arg_default_options = NULL;
+static char *arg_default_keyfile = NULL;
 
 static bool has_option(const char *haystack, const char *needle) {
         const char *f = haystack;
@@ -70,75 +83,107 @@ static int create_disk(
                 const char *password,
                 const char *options) {
 
-        char *p = NULL, *n = NULL, *d = NULL, *u = NULL, *from = NULL, *to = NULL, *e = NULL;
+        _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;
-        FILE *f = NULL;
-        bool noauto, nofail;
 
         assert(name);
         assert(device);
 
         noauto = has_option(options, "noauto");
         nofail = has_option(options, "nofail");
+        tmp = has_option(options, "tmp");
+        swap = has_option(options, "swap");
 
-        n = unit_name_from_path_instance("systemd-cryptsetup", name, ".service");
-        if (!n) {
-                r = -ENOMEM;
-                log_error("Failed to allocate unit name.");
-                goto fail;
+        if (tmp && swap) {
+                log_error("Device '%s' cannot be both 'tmp' and 'swap'. Ignoring.", name);
+                return -EINVAL;
         }
 
-        p = join(arg_dest, "/", n, NULL);
-        if (!p) {
-                r = -ENOMEM;
-                log_error("Failed to allocate unit file name.");
-                goto fail;
-        }
+        e = unit_name_escape(name);
+        if (!e)
+                return log_oom();
+
+        n = unit_name_build("systemd-cryptsetup", e, ".service");
+        if (!n)
+                return log_oom();
+
+        p = strjoin(arg_dest, "/", n, NULL);
+        if (!p)
+                return log_oom();
 
         u = fstab_node_to_udev_node(device);
-        if (!u) {
-                r = -ENOMEM;
-                log_error("Failed to allocate device node.");
-                goto fail;
-        }
+        if (!u)
+                return log_oom();
 
         d = unit_name_from_path(u, ".device");
-        if (!d) {
-                r = -ENOMEM;
-                log_error("Failed to allocate device name.");
-                goto fail;
-        }
+        if (!d)
+                return log_oom();
 
         f = fopen(p, "wxe");
-        if (!f) {
-                r = -errno;
-                log_error("Failed to create unit file: %m");
-                goto fail;
-        }
+        if (!f)
+                return log_error_errno(errno, "Failed to create unit file %s: %m", p);
 
-        fprintf(f,
+        fputs(
                 "# Automatically generated by systemd-cryptsetup-generator\n\n"
                 "[Unit]\n"
-                "Description=Cryptography Setup for %%I\n"
-                "Documentation=man:systemd-cryptsetup@.service(8)\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"
-                "Conflicts=umount.target\n"
                 "DefaultDependencies=no\n"
-                "BindTo=%s dev-mapper-%%i.device\n"
-                "After=systemd-readahead-collect.service systemd-readahead-replay.service %s\n"
-                "Before=umount.target\n",
-                d, d);
+                "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 && (streq(password, "/dev/urandom") ||
-                         streq(password, "/dev/random") ||
-                         streq(password, "/dev/hw_random")))
-                fputs("After=systemd-random-seed-load.service\n", f);
+        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;
+
+                                        dd = unit_name_from_path(uu, ".device");
+                                        if (!dd)
+                                                return log_oom();
+
+                                        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
-                fputs("Before=local-fs.target\n", f);
+                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"
@@ -147,305 +192,321 @@ static int create_disk(
                 "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(options),
+                name, u, strempty(password), strempty(filtered),
                 name);
 
-        if (has_option(options, "tmp"))
+        if (tmp)
                 fprintf(f,
                         "ExecStartPost=/sbin/mke2fs '/dev/mapper/%s'\n",
                         name);
 
-        if (has_option(options, "swap"))
+        if (swap)
                 fprintf(f,
                         "ExecStartPost=/sbin/mkswap '/dev/mapper/%s'\n",
                         name);
 
         fflush(f);
+        if (ferror(f))
+                return log_error_errno(errno, "Failed to write file %s: %m", p);
 
-        if (ferror(f)) {
-                r = -errno;
-                log_error("Failed to write file: %m");
-                goto fail;
-        }
-
-        if (asprintf(&from, "../%s", n) < 0) {
-                r = -ENOMEM;
-                goto fail;
-        }
+        from = strappenda("../", n);
 
         if (!noauto) {
 
-                to = join(arg_dest, "/", d, ".wants/", n, NULL);
-                if (!to) {
-                        r = -ENOMEM;
-                        goto fail;
-                }
+                to = strjoin(arg_dest, "/", d, ".wants/", n, NULL);
+                if (!to)
+                        return log_oom();
 
                 mkdir_parents_label(to, 0755);
-                if (symlink(from, to) < 0) {
-                        log_error("Failed to create symlink '%s' to '%s': %m", from, to);
-                        r = -errno;
-                        goto fail;
-                }
+                if (symlink(from, to) < 0)
+                        return log_error_errno(errno, "Failed to create symlink %s: %m", to);
 
                 free(to);
-
                 if (!nofail)
-                        to = join(arg_dest, "/cryptsetup.target.requires/", n, NULL);
+                        to = strjoin(arg_dest, "/cryptsetup.target.requires/", n, NULL);
                 else
-                        to = join(arg_dest, "/cryptsetup.target.wants/", n, NULL);
-                if (!to) {
-                        r = -ENOMEM;
-                        goto fail;
-                }
+                        to = strjoin(arg_dest, "/cryptsetup.target.wants/", n, NULL);
+                if (!to)
+                        return log_oom();
 
                 mkdir_parents_label(to, 0755);
-                if (symlink(from, to) < 0) {
-                        log_error("Failed to create symlink '%s' to '%s': %m", from, to);
-                        r = -errno;
-                        goto fail;
-                }
-
-                free(to);
-                to = NULL;
+                if (symlink(from, to) < 0)
+                        return log_error_errno(errno, "Failed to create symlink %s: %m", to);
         }
 
-        e = unit_name_escape(name);
-        to = join(arg_dest, "/dev-mapper-", e, ".device.requires/", n, NULL);
-        if (!to) {
-                r = -ENOMEM;
-                goto fail;
-        }
+        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) {
-                log_error("Failed to create symlink '%s' to '%s': %m", from, to);
-                r = -errno;
-                goto fail;
+        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");
         }
 
-        r = 0;
-
-fail:
-        free(p);
-        free(n);
-        free(d);
-        free(e);
+        return 0;
+}
 
-        free(from);
-        free(to);
+static void free_arg_disks(void) {
+        crypto_device *d;
 
-        if (f)
-                fclose(f);
+        while ((d = hashmap_steal_first(arg_disks))) {
+                free(d->uuid);
+                free(d->options);
+                free(d);
+        }
 
-        return r;
+        hashmap_free(arg_disks);
 }
 
-static int parse_proc_cmdline(void) {
-        char *line, *w, *state;
+static crypto_device *get_crypto_device(const char *uuid) {
         int r;
-        size_t l;
+        crypto_device *d;
 
-        if (detect_container(NULL) > 0)
-                return 0;
+        assert(uuid);
 
-        r = read_one_line_file("/proc/cmdline", &line);
-        if (r < 0) {
-                log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
-                return 0;
-        }
+        d = hashmap_get(arg_disks, uuid);
+        if (!d) {
+                d = new0(struct crypto_device, 1);
+                if (!d)
+                        return NULL;
 
-        FOREACH_WORD_QUOTED(w, l, line, state) {
-                char *word;
+                d->create = false;
+                d->options = NULL;
 
-                word = strndup(w, l);
-                if (!word) {
-                        r = -ENOMEM;
-                        goto finish;
+                d->uuid = strdup(uuid);
+                if (!d->uuid) {
+                        free(d);
+                        return NULL;
                 }
 
-                if (startswith(word, "luks=")) {
-                        r = parse_boolean(word + 5);
-                        if (r < 0)
-                                log_warning("Failed to parse luks switch %s. Ignoring.", word + 5);
-                        else
-                                arg_enabled = r;
-
-                } else if (startswith(word, "rd.luks=")) {
-
-                        if (in_initrd()) {
-                                r = parse_boolean(word + 8);
-                                if (r < 0)
-                                        log_warning("Failed to parse luks switch %s. Ignoring.", word + 8);
-                                else
-                                        arg_enabled = r;
-                        }
-
-                } else if (startswith(word, "luks.crypttab=")) {
-                        r = parse_boolean(word + 14);
-                        if (r < 0)
-                                log_warning("Failed to parse luks crypttab switch %s. Ignoring.", word + 14);
-                        else
-                                arg_read_crypttab = r;
-
-                } else if (startswith(word, "rd.luks.crypttab=")) {
-
-                        if (in_initrd()) {
-                                r = parse_boolean(word + 17);
-                                if (r < 0)
-                                        log_warning("Failed to parse luks crypttab switch %s. Ignoring.", word + 17);
-                                else
-                                        arg_read_crypttab = r;
-                        }
-
-                } else if (startswith(word, "luks.uuid=")) {
-                        char **t;
-
-                        t = strv_append(arg_proc_cmdline_disks, word + 10);
-                        if (!t) {
-                                log_error("Out of memory");
-                                r = -ENOMEM;
-                                goto finish;
-                        }
-                        strv_free(arg_proc_cmdline_disks);
-                        arg_proc_cmdline_disks = t;
-
-                } else if (startswith(word, "rd.luks.uuid=")) {
-
-                        if (in_initrd()) {
-                                char **t;
-
-                                t = strv_append(arg_proc_cmdline_disks, word + 13);
-                                if (!t) {
-                                        log_error("Out of memory");
-                                        r = -ENOMEM;
-                                        goto finish;
-                                }
-                                strv_free(arg_proc_cmdline_disks);
-                                arg_proc_cmdline_disks = t;
-                        }
-
-                } else if (startswith(word, "luks.") ||
-                           (in_initrd() && startswith(word, "rd.luks."))) {
-
-                        log_warning("Unknown kernel switch %s. Ignoring.", word);
+                r = hashmap_put(arg_disks, d->uuid, d);
+                if (r < 0) {
+                        free(d->uuid);
+                        free(d);
+                        return NULL;
                 }
-
-                free(word);
         }
 
-        r = 0;
-
-finish:
-        free(line);
-        return r;
+        return d;
 }
 
-int main(int argc, char *argv[]) {
-        FILE *f = NULL;
-        int r = EXIT_SUCCESS;
-        unsigned n = 0;
-        char **i;
+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 (argc > 1 && argc != 4) {
-                log_error("This program takes three or no arguments.");
-                return EXIT_FAILURE;
-        }
+        if (STR_IN_SET(key, "luks", "rd.luks") && value) {
 
-        if (argc > 1)
-                arg_dest = argv[1];
+                r = parse_boolean(value);
+                if (r < 0)
+                        log_warning("Failed to parse luks switch %s. Ignoring.", value);
+                else
+                        arg_enabled = r;
 
-        log_set_target(LOG_TARGET_SAFE);
-        log_parse_environment();
-        log_open();
+        } else if (STR_IN_SET(key, "luks.crypttab", "rd.luks.crypttab") && value) {
 
-        umask(0022);
+                r = parse_boolean(value);
+                if (r < 0)
+                        log_warning("Failed to parse luks crypttab switch %s. Ignoring.", value);
+                else
+                        arg_read_crypttab = r;
 
-        if (parse_proc_cmdline() < 0)
-                return EXIT_FAILURE;
+        } else if (STR_IN_SET(key, "luks.uuid", "rd.luks.uuid") && value) {
 
-        if (!arg_enabled) {
-                r = EXIT_SUCCESS;
-                goto finish;
-        }
+                d = get_crypto_device(startswith(value, "luks-") ? value+5 : value);
+                if (!d)
+                        return log_oom();
 
-        STRV_FOREACH(i, arg_proc_cmdline_disks) {
-                char *name, *device;
-                const char *p = *i;
+                d->create = arg_whitelist = true;
 
-                if (startswith(p, "luks-"))
-                        p += 5;
+        } else if (STR_IN_SET(key, "luks.options", "rd.luks.options") && value) {
 
-                name = strappend("luks-", *i);
-                device = strappend("UUID=", *i);
+                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();
 
-                if (!name || !device) {
-                        log_error("Out of memory");
-                        r = EXIT_FAILURE;
-                        free(name);
-                        free(device);
-                        goto finish;
-                }
+                        free(d->options);
+                        d->options = uuid_value;
+                        uuid_value = NULL;
+                } else if (free_and_strdup(&arg_default_options, value) < 0)
+                        return log_oom();
 
-                if (create_disk(name, device, NULL, NULL) < 0)
-                        r = EXIT_FAILURE;
+        } else if (STR_IN_SET(key, "luks.key", "rd.luks.key") && value) {
+
+                if (free_and_strdup(&arg_default_keyfile, value))
+                        return log_oom();
 
-                free(name);
-                free(device);
         }
 
+        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 r;
+                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 (errno == ENOENT)
-                        r = EXIT_SUCCESS;
-                else {
-                        r = EXIT_FAILURE;
-                        log_error("Failed to open /etc/crypttab: %m");
-                }
-
-                goto finish;
+        if (fstat(fileno(f), &st) < 0) {
+                log_error_errno(errno, "Failed to stat /etc/crypttab: %m");
+                return 0;
         }
 
+        /* If we readd support for specifying passphrases
+         * directly in crypttab we should upgrade the warning
+         * below, though possibly only if a passphrase is
+         * specified directly. */
+        if (st.st_mode & 0005)
+                log_debug("/etc/crypttab is world-readable. This is usually not a good idea.");
+
         for (;;) {
-                char line[LINE_MAX], *l;
-                char *name = NULL, *device = NULL, *password = NULL, *options = NULL;
-                int k;
+                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;
 
-                n++;
+                crypttab_line++;
 
                 l = strstrip(line);
                 if (*l == '#' || *l == 0)
                         continue;
 
-                k = sscanf(l, "%ms %ms %ms %ms", &name, &device, &password, &options);
+                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.", n);
-                        r = EXIT_FAILURE;
-                        goto next;
+                        log_error("Failed to parse /etc/crypttab:%u, ignoring.", crypttab_line);
+                        continue;
                 }
 
-                if (create_disk(name, device, password, options) < 0)
-                        r = EXIT_FAILURE;
+                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 *name = NULL, *device = NULL;
+
+                if (!d->create)
+                        continue;
+
+                name = strappend("luks-", d->uuid);
+                if (!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(name, device, 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;
 
-        next:
-                free(name);
-                free(device);
-                free(password);
-                free(options);
+        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;
         }
 
-finish:
-        if (f)
-                fclose(f);
+        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;
 
-        strv_free(arg_proc_cmdline_disks);
+cleanup:
+        free_arg_disks();
+        free(arg_default_options);
+        free(arg_default_keyfile);
 
         return r;
 }