diff options
Diffstat (limited to 'src/integritysetup/integritysetup-generator.c')
| -rw-r--r-- | src/integritysetup/integritysetup-generator.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/src/integritysetup/integritysetup-generator.c b/src/integritysetup/integritysetup-generator.c new file mode 100644 index 0000000..72b8905 --- /dev/null +++ b/src/integritysetup/integritysetup-generator.c @@ -0,0 +1,176 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <errno.h> +#include <stdbool.h> +#include <stdlib.h> +#include <sys/stat.h> +#include <unistd.h> + +#include "alloc-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "fstab-util.h" +#include "generator.h" +#include "hexdecoct.h" +#include "id128-util.h" +#include "integrity-util.h" +#include "main-func.h" +#include "mkdir.h" +#include "parse-util.h" +#include "path-util.h" +#include "proc-cmdline.h" +#include "specifier.h" +#include "string-util.h" +#include "unit-name.h" + +static const char *arg_dest = NULL; +static const char *arg_integritytab = NULL; +static char *arg_options = NULL; +STATIC_DESTRUCTOR_REGISTER(arg_options, freep); + +static int create_disk( + const char *name, + const char *device, + const char *key_file, + const char *options) { + + _cleanup_free_ char *n = NULL, *dd = NULL, *e = NULL, *name_escaped = NULL, *key_file_escaped = NULL; + _cleanup_fclose_ FILE *f = NULL; + int r; + char *dmname = NULL; + + assert(name); + assert(device); + + name_escaped = specifier_escape(name); + if (!name_escaped) + return log_oom(); + + e = unit_name_escape(name); + if (!e) + return log_oom(); + + r = unit_name_build("systemd-integritysetup", e, ".service", &n); + if (r < 0) + return log_error_errno(r, "Failed to generate unit name: %m"); + + r = unit_name_from_path(device, ".device", &dd); + if (r < 0) + return log_error_errno(r, "Failed to generate unit name: %m"); + + r = generator_open_unit_file(arg_dest, NULL, n, &f); + if (r < 0) + return r; + + if (key_file) { + if (!path_is_absolute(key_file)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "key file not absolute file path %s", key_file); + + key_file_escaped = specifier_escape(key_file); + if (!key_file_escaped) + return log_oom(); + } + + if (options) { + r = parse_integrity_options(options, NULL, NULL, NULL, NULL, NULL); + if (r < 0) + return r; + } + + fprintf(f, + "[Unit]\n" + "Description=Integrity Setup for %%I\n" + "Documentation=man:integritytab(5) man:systemd-integritysetup-generator(8) man:systemd-integritysetup@.service(8)\n" + "SourcePath=%s\n" + "DefaultDependencies=no\n" + "IgnoreOnIsolate=true\n" + "After=integritysetup-pre.target systemd-udevd-kernel.socket\n" + "Before=blockdev@dev-mapper-%%i.target\n" + "Wants=blockdev@dev-mapper-%%i.target\n" + "Conflicts=umount.target\n" + "Before=integritysetup.target\n" + "BindsTo=%s\n" + "After=%s\n" + "Before=umount.target\n", + arg_integritytab, + dd, dd); + + fprintf(f, + "\n" + "[Service]\n" + "Type=oneshot\n" + "RemainAfterExit=yes\n" + "TimeoutSec=infinity\n" + "ExecStart=" LIBEXECDIR "/systemd-integritysetup attach '%s' '%s' '%s' '%s'\n" + "ExecStop=" LIBEXECDIR "/systemd-integritysetup detach '%s'\n", + name_escaped, device, empty_to_dash(key_file_escaped), empty_to_dash(options), + name_escaped); + + r = fflush_and_check(f); + if (r < 0) + return log_error_errno(r, "Failed to write unit file %s: %m", n); + + r = generator_add_symlink(arg_dest, "integritysetup.target", "requires", n); + if (r < 0) + return r; + + dmname = strjoina("dev-mapper-", e, ".device"); + return generator_add_symlink(arg_dest, dmname, "requires", n); +} + +static int add_integritytab_devices(void) { + _cleanup_fclose_ FILE *f = NULL; + unsigned integritytab_line = 0; + int r; + + r = fopen_unlocked(arg_integritytab, "re", &f); + if (r < 0) { + if (errno != ENOENT) + log_error_errno(errno, "Failed to open %s: %m", arg_integritytab); + return 0; + } + + for (;;) { + _cleanup_free_ char *line = NULL, *name = NULL, *device_id = NULL, *device_path = NULL, *key_file = NULL, *options = NULL; + + r = read_stripped_line(f, LONG_LINE_MAX, &line); + if (r < 0) + return log_error_errno(r, "Failed to read %s: %m", arg_integritytab); + if (r == 0) + break; + + integritytab_line++; + + if (IN_SET(line[0], 0, '#')) + continue; + + /* The key file and the options are optional */ + r = sscanf(line, "%ms %ms %ms %ms", &name, &device_id, &key_file, &options); + if (!IN_SET(r, 2, 3, 4)) { + log_error("Failed to parse %s:%u, ignoring.", arg_integritytab, integritytab_line); + continue; + } + + device_path = fstab_node_to_udev_node(device_id); + if (!device_path) { + log_error("Failed to find device %s:%u, ignoring.", device_id, integritytab_line); + continue; + } + + r = create_disk(name, device_path, empty_or_dash_to_null(key_file), empty_or_dash_to_null(options)); + if (r < 0) + return r; + } + + return 0; +} + +static int run(const char *dest, const char *dest_early, const char *dest_late) { + assert_se(arg_dest = dest); + + arg_integritytab = getenv("SYSTEMD_INTEGRITYTAB") ?: "/etc/integritytab"; + + return add_integritytab_devices(); +} + +DEFINE_MAIN_GENERATOR_FUNCTION(run); |