diff options
Diffstat (limited to 'src/shared/generator.c')
| -rw-r--r-- | src/shared/generator.c | 631 |
1 files changed, 631 insertions, 0 deletions
diff --git a/src/shared/generator.c b/src/shared/generator.c new file mode 100644 index 0000000..1eccc5a --- /dev/null +++ b/src/shared/generator.c @@ -0,0 +1,631 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <errno.h> +#include <unistd.h> + +#include "alloc-util.h" +#include "cgroup-util.h" +#include "dropin.h" +#include "escape.h" +#include "fd-util.h" +#include "fileio.h" +#include "fstab-util.h" +#include "generator.h" +#include "log.h" +#include "macro.h" +#include "mkdir.h" +#include "path-util.h" +#include "special.h" +#include "specifier.h" +#include "string-util.h" +#include "time-util.h" +#include "unit-name.h" +#include "util.h" + +int generator_open_unit_file( + const char *dest, + const char *source, + const char *name, + FILE **file) { + + const char *unit; + FILE *f; + int r; + + unit = prefix_roota(dest, name); + + r = fopen_unlocked(unit, "wxe", &f); + if (r < 0) { + if (source && r == -EEXIST) + return log_error_errno(r, + "Failed to create unit file %s, as it already exists. Duplicate entry in %s?", + unit, source); + else + return log_error_errno(r, + "Failed to create unit file %s: %m", + unit); + } + + fprintf(f, + "# Automatically generated by %s\n\n", + program_invocation_short_name); + + *file = f; + return 0; +} + +int generator_add_symlink(const char *dir, const char *dst, const char *dep_type, const char *src) { + /* Adds a symlink from <dst>.<dep_type>/ to <src> (if src is absolute) + * or ../<src> (otherwise). */ + + const char *from, *to; + + from = path_is_absolute(src) ? src : strjoina("../", src); + to = strjoina(dir, "/", dst, ".", dep_type, "/", basename(src)); + + mkdir_parents_label(to, 0755); + if (symlink(from, to) < 0) + if (errno != EEXIST) + return log_error_errno(errno, "Failed to create symlink \"%s\": %m", to); + + return 0; +} + +static int write_fsck_sysroot_service(const char *dir, const char *what) { + _cleanup_free_ char *device = NULL, *escaped = NULL, *escaped2 = NULL; + _cleanup_fclose_ FILE *f = NULL; + const char *unit; + int r; + + escaped = specifier_escape(what); + if (!escaped) + return log_oom(); + + escaped2 = cescape(escaped); + if (!escaped2) + return log_oom(); + + unit = strjoina(dir, "/"SPECIAL_FSCK_ROOT_SERVICE); + log_debug("Creating %s", unit); + + r = unit_name_from_path(what, ".device", &device); + if (r < 0) + return log_error_errno(r, "Failed to convert device \"%s\" to unit name: %m", what); + + f = fopen(unit, "wxe"); + if (!f) + return log_error_errno(errno, "Failed to create unit file %s: %m", unit); + + fprintf(f, + "# Automatically generated by %1$s\n\n" + "[Unit]\n" + "Description=File System Check on %2$s\n" + "Documentation=man:systemd-fsck-root.service(8)\n" + "DefaultDependencies=no\n" + "BindsTo=%3$s\n" + "Conflicts=shutdown.target\n" + "After=initrd-root-device.target local-fs-pre.target %3$s\n" + "Before=shutdown.target\n" + "\n" + "[Service]\n" + "Type=oneshot\n" + "RemainAfterExit=yes\n" + "ExecStart=" SYSTEMD_FSCK_PATH " %4$s\n" + "TimeoutSec=0\n", + program_invocation_short_name, + escaped, + device, + escaped2); + + r = fflush_and_check(f); + if (r < 0) + return log_error_errno(r, "Failed to write unit file %s: %m", unit); + + return 0; +} + +int generator_write_fsck_deps( + FILE *f, + const char *dir, + const char *what, + const char *where, + const char *fstype) { + + int r; + + assert(f); + assert(dir); + assert(what); + assert(where); + + if (!is_device_path(what)) { + log_warning("Checking was requested for \"%s\", but it is not a device.", what); + return 0; + } + + if (!isempty(fstype) && !streq(fstype, "auto")) { + r = fsck_exists(fstype); + if (r < 0) + log_warning_errno(r, "Checking was requested for %s, but couldn't detect if fsck.%s may be used, proceeding: %m", what, fstype); + else if (r == 0) { + /* treat missing check as essentially OK */ + log_debug("Checking was requested for %s, but fsck.%s does not exist.", what, fstype); + return 0; + } + } + + if (path_equal(where, "/")) { + const char *lnk; + + lnk = strjoina(dir, "/" SPECIAL_LOCAL_FS_TARGET ".wants/" SPECIAL_FSCK_ROOT_SERVICE); + + (void) mkdir_parents(lnk, 0755); + if (symlink(SYSTEM_DATA_UNIT_PATH "/" SPECIAL_FSCK_ROOT_SERVICE, lnk) < 0) + return log_error_errno(errno, "Failed to create symlink %s: %m", lnk); + + } else { + _cleanup_free_ char *_fsck = NULL; + const char *fsck, *dep; + + if (in_initrd() && path_equal(where, "/sysroot")) { + r = write_fsck_sysroot_service(dir, what); + if (r < 0) + return r; + + fsck = SPECIAL_FSCK_ROOT_SERVICE; + dep = "Requires"; + } else { + /* When this is /usr, then let's add a Wants= dependency, otherwise a Requires= + * dependency. Why? We can't possibly unmount /usr during shutdown, but if we have a + * Requires= from /usr onto a fsck@.service unit and that unit is shut down, then + * we'd have to unmount /usr too. */ + + dep = !in_initrd() && path_equal(where, "/usr") ? "Wants" : "Requires"; + + r = unit_name_from_path_instance("systemd-fsck", what, ".service", &_fsck); + if (r < 0) + return log_error_errno(r, "Failed to create fsck service name: %m"); + + fsck = _fsck; + } + + fprintf(f, + "%1$s=%2$s\n" + "After=%2$s\n", + dep, fsck); + } + + return 0; +} + +int generator_write_timeouts( + const char *dir, + const char *what, + const char *where, + const char *opts, + char **filtered) { + + /* Configure how long we wait for a device that backs a mount point or a + * swap partition to show up. This is useful to support endless device timeouts + * for devices that show up only after user input, like crypto devices. */ + + _cleanup_free_ char *node = NULL, *unit = NULL, *timeout = NULL; + usec_t u; + int r; + + r = fstab_filter_options(opts, "comment=systemd.device-timeout\0" + "x-systemd.device-timeout\0", + NULL, &timeout, filtered); + if (r <= 0) + return r; + + r = parse_sec_fix_0(timeout, &u); + if (r < 0) { + log_warning("Failed to parse timeout for %s, ignoring: %s", where, timeout); + return 0; + } + + node = fstab_node_to_udev_node(what); + if (!node) + return log_oom(); + if (!is_device_path(node)) { + log_warning("x-systemd.device-timeout ignored for %s", what); + return 0; + } + + r = unit_name_from_path(node, ".device", &unit); + if (r < 0) + return log_error_errno(r, "Failed to make unit name from path: %m"); + + return write_drop_in_format(dir, unit, 50, "device-timeout", + "# Automatically generated by %s\n" + "# from supplied options \"%s\"\n\n" + "[Unit]\n" + "JobRunningTimeoutSec=%s", + program_invocation_short_name, + opts, + timeout); +} + +int generator_write_device_deps( + const char *dir, + const char *what, + const char *where, + const char *opts) { + + /* fstab records that specify _netdev option should apply the network + * ordering on the actual device depending on network connection. If we + * are not mounting real device (NFS, CIFS), we rely on _netdev effect + * on the mount unit itself. */ + + _cleanup_free_ char *node = NULL, *unit = NULL; + int r; + + if (fstab_is_extrinsic(where, opts)) + return 0; + + if (!fstab_test_option(opts, "_netdev\0")) + return 0; + + node = fstab_node_to_udev_node(what); + if (!node) + return log_oom(); + + /* Nothing to apply dependencies to. */ + if (!is_device_path(node)) + return 0; + + r = unit_name_from_path(node, ".device", &unit); + if (r < 0) + return log_error_errno(r, "Failed to make unit name from path \"%s\": %m", + node); + + /* See mount_add_default_dependencies for explanation why we create such + * dependencies. */ + return write_drop_in_format(dir, unit, 50, "netdev-dependencies", + "# Automatically generated by %s\n\n" + "[Unit]\n" + "After=" SPECIAL_NETWORK_ONLINE_TARGET " " SPECIAL_NETWORK_TARGET "\n" + "Wants=" SPECIAL_NETWORK_ONLINE_TARGET "\n", + program_invocation_short_name); +} + +int generator_write_initrd_root_device_deps(const char *dir, const char *what) { + _cleanup_free_ char *unit = NULL; + int r; + + r = unit_name_from_path(what, ".device", &unit); + if (r < 0) + return log_error_errno(r, "Failed to make unit name from path \"%s\": %m", + what); + + return write_drop_in_format(dir, SPECIAL_INITRD_ROOT_DEVICE_TARGET, 50, "root-device", + "# Automatically generated by %s\n\n" + "[Unit]\n" + "Requires=%s\n" + "After=%s", + program_invocation_short_name, + unit, + unit); +} + +int generator_hook_up_mkswap( + const char *dir, + const char *what) { + + _cleanup_free_ char *node = NULL, *unit = NULL, *escaped = NULL, *where_unit = NULL; + _cleanup_fclose_ FILE *f = NULL; + const char *unit_file; + int r; + + node = fstab_node_to_udev_node(what); + if (!node) + return log_oom(); + + /* Nothing to work on. */ + if (!is_device_path(node)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "Cannot format something that is not a device node: %s", + node); + + r = unit_name_from_path_instance("systemd-mkswap", node, ".service", &unit); + if (r < 0) + return log_error_errno(r, "Failed to make unit instance name from path \"%s\": %m", + node); + + unit_file = prefix_roota(dir, unit); + log_debug("Creating %s", unit_file); + + escaped = cescape(node); + if (!escaped) + return log_oom(); + + r = unit_name_from_path(what, ".swap", &where_unit); + if (r < 0) + return log_error_errno(r, "Failed to make unit name from path \"%s\": %m", + what); + + f = fopen(unit_file, "wxe"); + if (!f) + return log_error_errno(errno, "Failed to create unit file %s: %m", + unit_file); + + fprintf(f, + "# Automatically generated by %s\n\n" + "[Unit]\n" + "Description=Make Swap on %%f\n" + "Documentation=man:systemd-mkswap@.service(8)\n" + "DefaultDependencies=no\n" + "BindsTo=%%i.device\n" + "Conflicts=shutdown.target\n" + "After=%%i.device\n" + "Before=shutdown.target %s\n" + "\n" + "[Service]\n" + "Type=oneshot\n" + "RemainAfterExit=yes\n" + "ExecStart="SYSTEMD_MAKEFS_PATH " swap %s\n" + "TimeoutSec=0\n", + program_invocation_short_name, + where_unit, + escaped); + + r = fflush_and_check(f); + if (r < 0) + return log_error_errno(r, "Failed to write unit file %s: %m", unit_file); + + return generator_add_symlink(dir, where_unit, "requires", unit); +} + +int generator_hook_up_mkfs( + const char *dir, + const char *what, + const char *where, + const char *type) { + + _cleanup_free_ char *node = NULL, *unit = NULL, *escaped = NULL, *where_unit = NULL; + _cleanup_fclose_ FILE *f = NULL; + const char *unit_file; + int r; + + node = fstab_node_to_udev_node(what); + if (!node) + return log_oom(); + + /* Nothing to work on. */ + if (!is_device_path(node)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "Cannot format something that is not a device node: %s", + node); + + if (!type || streq(type, "auto")) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "Cannot format partition %s, filesystem type is not specified", + node); + + r = unit_name_from_path_instance("systemd-makefs", node, ".service", &unit); + if (r < 0) + return log_error_errno(r, "Failed to make unit instance name from path \"%s\": %m", + node); + + unit_file = prefix_roota(dir, unit); + log_debug("Creating %s", unit_file); + + escaped = cescape(node); + if (!escaped) + return log_oom(); + + r = unit_name_from_path(where, ".mount", &where_unit); + if (r < 0) + return log_error_errno(r, "Failed to make unit name from path \"%s\": %m", + where); + + f = fopen(unit_file, "wxe"); + if (!f) + return log_error_errno(errno, "Failed to create unit file %s: %m", + unit_file); + + fprintf(f, + "# Automatically generated by %s\n\n" + "[Unit]\n" + "Description=Make File System on %%f\n" + "Documentation=man:systemd-makefs@.service(8)\n" + "DefaultDependencies=no\n" + "BindsTo=%%i.device\n" + "Conflicts=shutdown.target\n" + "After=%%i.device\n" + /* fsck might or might not be used, so let's be safe and order + * ourselves before both systemd-fsck@.service and the mount unit. */ + "Before=shutdown.target systemd-fsck@%%i.service %s\n" + "\n" + "[Service]\n" + "Type=oneshot\n" + "RemainAfterExit=yes\n" + "ExecStart="SYSTEMD_MAKEFS_PATH " %s %s\n" + "TimeoutSec=0\n", + program_invocation_short_name, + where_unit, + type, + escaped); + // XXX: what about local-fs-pre.target? + + r = fflush_and_check(f); + if (r < 0) + return log_error_errno(r, "Failed to write unit file %s: %m", unit_file); + + return generator_add_symlink(dir, where_unit, "requires", unit); +} + +int generator_hook_up_growfs( + const char *dir, + const char *where, + const char *target) { + + _cleanup_free_ char *unit = NULL, *escaped = NULL, *where_unit = NULL; + _cleanup_fclose_ FILE *f = NULL; + const char *unit_file; + int r; + + escaped = cescape(where); + if (!escaped) + return log_oom(); + + r = unit_name_from_path_instance("systemd-growfs", where, ".service", &unit); + if (r < 0) + return log_error_errno(r, "Failed to make unit instance name from path \"%s\": %m", + where); + + r = unit_name_from_path(where, ".mount", &where_unit); + if (r < 0) + return log_error_errno(r, "Failed to make unit name from path \"%s\": %m", + where); + + unit_file = prefix_roota(dir, unit); + log_debug("Creating %s", unit_file); + + f = fopen(unit_file, "wxe"); + if (!f) + return log_error_errno(errno, "Failed to create unit file %s: %m", + unit_file); + + fprintf(f, + "# Automatically generated by %s\n\n" + "[Unit]\n" + "Description=Grow File System on %%f\n" + "Documentation=man:systemd-growfs@.service(8)\n" + "DefaultDependencies=no\n" + "BindsTo=%%i.mount\n" + "Conflicts=shutdown.target\n" + "After=%%i.mount\n" + "Before=shutdown.target %s\n", + program_invocation_short_name, + target); + + if (empty_or_root(where)) /* Make sure the root fs is actually writable before we resize it */ + fprintf(f, + "After=systemd-remount-fs.service\n"); + + fprintf(f, + "\n" + "[Service]\n" + "Type=oneshot\n" + "RemainAfterExit=yes\n" + "ExecStart="SYSTEMD_GROWFS_PATH " %s\n" + "TimeoutSec=0\n", + escaped); + + return generator_add_symlink(dir, where_unit, "wants", unit); +} + +int generator_enable_remount_fs_service(const char *dir) { + /* Pull in systemd-remount-fs.service */ + return generator_add_symlink(dir, SPECIAL_LOCAL_FS_TARGET, "wants", + SYSTEM_DATA_UNIT_PATH "/" SPECIAL_REMOUNT_FS_SERVICE); +} + +int generator_write_blockdev_dependency( + FILE *f, + const char *what) { + + _cleanup_free_ char *escaped = NULL; + int r; + + assert(f); + assert(what); + + if (!path_startswith(what, "/dev/")) + return 0; + + r = unit_name_path_escape(what, &escaped); + if (r < 0) + return log_error_errno(r, "Failed to escape device node path %s: %m", what); + + fprintf(f, + "After=blockdev@%s.target\n", + escaped); + + return 0; +} + +int generator_write_cryptsetup_unit_section( + FILE *f, + const char *source) { + + assert(f); + + fprintf(f, + "[Unit]\n" + "Description=Cryptography Setup for %%I\n" + "Documentation=man:crypttab(5) man:systemd-cryptsetup-generator(8) man:systemd-cryptsetup@.service(8)\n"); + + if (source) + fprintf(f, "SourcePath=%s\n", source); + + fprintf(f, + "DefaultDependencies=no\n" + "IgnoreOnIsolate=true\n" + "After=cryptsetup-pre.target systemd-udevd-kernel.socket\n" + "Before=blockdev@dev-mapper-%%i.target\n" + "Wants=blockdev@dev-mapper-%%i.target\n"); + + return 0; +} + +int generator_write_cryptsetup_service_section( + FILE *f, + const char *name, + const char *what, + const char *password, + const char *options) { + + _cleanup_free_ char *name_escaped = NULL, *what_escaped = NULL, *password_escaped = NULL, *options_escaped = NULL; + + assert(f); + assert(name); + assert(what); + + name_escaped = specifier_escape(name); + if (!name_escaped) + return log_oom(); + + what_escaped = specifier_escape(what); + if (!what_escaped) + return log_oom(); + + if (password) { + password_escaped = specifier_escape(password); + if (!password_escaped) + return log_oom(); + } + + if (options) { + options_escaped = specifier_escape(options); + if (!options_escaped) + return log_oom(); + } + + fprintf(f, + "\n" + "[Service]\n" + "Type=oneshot\n" + "RemainAfterExit=yes\n" + "TimeoutSec=0\n" /* The binary handles timeouts on its own */ + "KeyringMode=shared\n" /* Make sure we can share cached keys among instances */ + "OOMScoreAdjust=500\n" /* Unlocking can allocate a lot of memory if Argon2 is used */ + "ExecStart=" SYSTEMD_CRYPTSETUP_PATH " attach '%s' '%s' '%s' '%s'\n" + "ExecStop=" SYSTEMD_CRYPTSETUP_PATH " detach '%s'\n", + name_escaped, what_escaped, strempty(password_escaped), strempty(options_escaped), + name_escaped); + + return 0; +} + +void log_setup_generator(void) { + /* Disable talking to syslog/journal (i.e. the two IPC-based loggers) if we run in system context. */ + if (cg_pid_get_owner_uid(0, NULL) == -ENXIO /* not running in a per-user slice */) + log_set_prohibit_ipc(true); + + log_set_target(LOG_TARGET_JOURNAL_OR_KMSG); /* This effectively means: journal for per-user generators, kmsg otherwise */ + log_parse_environment(); + (void) log_open(); +} |