diff options
Diffstat (limited to 'src/systemd-fstab-generator/fstab-generator.c')
| -rw-r--r-- | src/systemd-fstab-generator/fstab-generator.c | 713 |
1 files changed, 713 insertions, 0 deletions
diff --git a/src/systemd-fstab-generator/fstab-generator.c b/src/systemd-fstab-generator/fstab-generator.c new file mode 100644 index 0000000000..108522873e --- /dev/null +++ b/src/systemd-fstab-generator/fstab-generator.c @@ -0,0 +1,713 @@ +/*** + This file is part of systemd. + + Copyright 2012 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 <mntent.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> + +#include "alloc-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "fstab-util.h" +#include "generator.h" +#include "log.h" +#include "mkdir.h" +#include "mount-setup.h" +#include "mount-util.h" +#include "parse-util.h" +#include "path-util.h" +#include "proc-cmdline.h" +#include "special.h" +#include "stat-util.h" +#include "string-util.h" +#include "strv.h" +#include "unit-name.h" +#include "util.h" +#include "virt.h" + +static const char *arg_dest = "/tmp"; +static bool arg_fstab_enabled = true; +static char *arg_root_what = NULL; +static char *arg_root_fstype = NULL; +static char *arg_root_options = NULL; +static int arg_root_rw = -1; +static char *arg_usr_what = NULL; +static char *arg_usr_fstype = NULL; +static char *arg_usr_options = NULL; + +static int add_swap( + const char *what, + struct mntent *me, + bool noauto, + bool nofail) { + + _cleanup_free_ char *name = NULL, *unit = NULL, *lnk = NULL; + _cleanup_fclose_ FILE *f = NULL; + int r; + + assert(what); + assert(me); + + if (access("/proc/swaps", F_OK) < 0) { + log_info("Swap not supported, ignoring fstab swap entry for %s.", what); + return 0; + } + + if (detect_container() > 0) { + log_info("Running in a container, ignoring fstab swap entry for %s.", what); + return 0; + } + + r = unit_name_from_path(what, ".swap", &name); + if (r < 0) + return log_error_errno(r, "Failed to generate unit name: %m"); + + unit = strjoin(arg_dest, "/", name, NULL); + if (!unit) + return log_oom(); + + f = fopen(unit, "wxe"); + if (!f) { + if (errno == EEXIST) + log_error("Failed to create swap unit file %s, as it already exists. Duplicate entry in /etc/fstab?", unit); + else + log_error_errno(errno, "Failed to create unit file %s: %m", unit); + return -errno; + } + + fprintf(f, + "# Automatically generated by systemd-fstab-generator\n\n" + "[Unit]\n" + "SourcePath=/etc/fstab\n" + "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n\n" + "[Swap]\n" + "What=%s\n", + what); + + if (!isempty(me->mnt_opts) && !streq(me->mnt_opts, "defaults")) + fprintf(f, "Options=%s\n", me->mnt_opts); + + r = fflush_and_check(f); + if (r < 0) + return log_error_errno(r, "Failed to write unit file %s: %m", unit); + + /* use what as where, to have a nicer error message */ + r = generator_write_timeouts(arg_dest, what, what, me->mnt_opts, NULL); + if (r < 0) + return r; + + if (!noauto) { + lnk = strjoin(arg_dest, "/" SPECIAL_SWAP_TARGET, + nofail ? ".wants/" : ".requires/", name, NULL); + if (!lnk) + return log_oom(); + + mkdir_parents_label(lnk, 0755); + if (symlink(unit, lnk) < 0) + return log_error_errno(errno, "Failed to create symlink %s: %m", lnk); + } + + return 0; +} + +static bool mount_is_network(struct mntent *me) { + assert(me); + + return fstab_test_option(me->mnt_opts, "_netdev\0") || + fstype_is_network(me->mnt_type); +} + +static bool mount_in_initrd(struct mntent *me) { + assert(me); + + return fstab_test_option(me->mnt_opts, "x-initrd.mount\0") || + streq(me->mnt_dir, "/usr"); +} + +static int write_idle_timeout(FILE *f, const char *where, const char *opts) { + _cleanup_free_ char *timeout = NULL; + char timespan[FORMAT_TIMESPAN_MAX]; + usec_t u; + int r; + + r = fstab_filter_options(opts, "x-systemd.idle-timeout\0", NULL, &timeout, NULL); + if (r < 0) + return log_warning_errno(r, "Failed to parse options: %m"); + if (r == 0) + return 0; + + r = parse_sec(timeout, &u); + if (r < 0) { + log_warning("Failed to parse timeout for %s, ignoring: %s", where, timeout); + return 0; + } + + fprintf(f, "TimeoutIdleSec=%s\n", format_timespan(timespan, sizeof(timespan), u, 0)); + + return 0; +} + +static int write_requires_after(FILE *f, const char *opts) { + _cleanup_strv_free_ char **names = NULL, **units = NULL; + _cleanup_free_ char *res = NULL; + char **s; + int r; + + assert(f); + assert(opts); + + r = fstab_extract_values(opts, "x-systemd.requires", &names); + if (r < 0) + return log_warning_errno(r, "Failed to parse options: %m"); + if (r == 0) + return 0; + + STRV_FOREACH(s, names) { + char *x; + + r = unit_name_mangle_with_suffix(*s, UNIT_NAME_NOGLOB, ".mount", &x); + if (r < 0) + return log_error_errno(r, "Failed to generate unit name: %m"); + r = strv_consume(&units, x); + if (r < 0) + return log_oom(); + } + + if (units) { + res = strv_join(units, " "); + if (!res) + return log_oom(); + fprintf(f, "After=%1$s\nRequires=%1$s\n", res); + } + + return 0; +} + +static int write_requires_mounts_for(FILE *f, const char *opts) { + _cleanup_strv_free_ char **paths = NULL; + _cleanup_free_ char *res = NULL; + int r; + + assert(f); + assert(opts); + + r = fstab_extract_values(opts, "x-systemd.requires-mounts-for", &paths); + if (r < 0) + return log_warning_errno(r, "Failed to parse options: %m"); + if (r == 0) + return 0; + + res = strv_join(paths, " "); + if (!res) + return log_oom(); + + fprintf(f, "RequiresMountsFor=%s\n", res); + + return 0; +} + +static int add_mount( + const char *what, + const char *where, + const char *fstype, + const char *opts, + int passno, + bool noauto, + bool nofail, + bool automount, + const char *post, + const char *source) { + + _cleanup_free_ char + *name = NULL, *unit = NULL, *lnk = NULL, + *automount_name = NULL, *automount_unit = NULL, + *filtered = NULL; + _cleanup_fclose_ FILE *f = NULL; + int r; + + assert(what); + assert(where); + assert(opts); + assert(post); + assert(source); + + if (streq_ptr(fstype, "autofs")) + return 0; + + if (!is_path(where)) { + log_warning("Mount point %s is not a valid path, ignoring.", where); + return 0; + } + + if (mount_point_is_api(where) || + mount_point_ignore(where)) + return 0; + + if (path_equal(where, "/")) { + if (noauto) + log_warning("Ignoring \"noauto\" for root device"); + if (nofail) + log_warning("Ignoring \"nofail\" for root device"); + if (automount) + log_warning("Ignoring automount option for root device"); + + noauto = nofail = automount = false; + } + + r = unit_name_from_path(where, ".mount", &name); + if (r < 0) + return log_error_errno(r, "Failed to generate unit name: %m"); + + unit = strjoin(arg_dest, "/", name, NULL); + if (!unit) + return log_oom(); + + f = fopen(unit, "wxe"); + if (!f) { + if (errno == EEXIST) + log_error("Failed to create mount unit file %s, as it already exists. Duplicate entry in /etc/fstab?", unit); + else + log_error_errno(errno, "Failed to create unit file %s: %m", unit); + return -errno; + } + + fprintf(f, + "# Automatically generated by systemd-fstab-generator\n\n" + "[Unit]\n" + "SourcePath=%s\n" + "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n", + source); + + if (!noauto && !nofail && !automount) + fprintf(f, "Before=%s\n", post); + + if (!automount && opts) { + r = write_requires_after(f, opts); + if (r < 0) + return r; + r = write_requires_mounts_for(f, opts); + if (r < 0) + return r; + } + + if (passno != 0) { + r = generator_write_fsck_deps(f, arg_dest, what, where, fstype); + if (r < 0) + return r; + } + + fprintf(f, + "\n" + "[Mount]\n" + "What=%s\n" + "Where=%s\n", + what, + where); + + if (!isempty(fstype) && !streq(fstype, "auto")) + fprintf(f, "Type=%s\n", fstype); + + r = generator_write_timeouts(arg_dest, what, where, opts, &filtered); + if (r < 0) + return r; + + if (!isempty(filtered) && !streq(filtered, "defaults")) + fprintf(f, "Options=%s\n", filtered); + + r = fflush_and_check(f); + if (r < 0) + return log_error_errno(r, "Failed to write unit file %s: %m", unit); + + if (!noauto && !automount) { + lnk = strjoin(arg_dest, "/", post, nofail ? ".wants/" : ".requires/", name, NULL); + if (!lnk) + return log_oom(); + + mkdir_parents_label(lnk, 0755); + if (symlink(unit, lnk) < 0) + return log_error_errno(errno, "Failed to create symlink %s: %m", lnk); + } + + if (automount) { + r = unit_name_from_path(where, ".automount", &automount_name); + if (r < 0) + return log_error_errno(r, "Failed to generate unit name: %m"); + + automount_unit = strjoin(arg_dest, "/", automount_name, NULL); + if (!automount_unit) + return log_oom(); + + fclose(f); + f = fopen(automount_unit, "wxe"); + if (!f) + return log_error_errno(errno, "Failed to create unit file %s: %m", automount_unit); + + fprintf(f, + "# Automatically generated by systemd-fstab-generator\n\n" + "[Unit]\n" + "SourcePath=%s\n" + "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n", + source); + + fprintf(f, "Before=%s\n", post); + + if (opts) { + r = write_requires_after(f, opts); + if (r < 0) + return r; + r = write_requires_mounts_for(f, opts); + if (r < 0) + return r; + } + + fprintf(f, + "\n" + "[Automount]\n" + "Where=%s\n", + where); + + r = write_idle_timeout(f, where, opts); + if (r < 0) + return r; + + r = fflush_and_check(f); + if (r < 0) + return log_error_errno(r, "Failed to write unit file %s: %m", automount_unit); + + free(lnk); + lnk = strjoin(arg_dest, "/", post, nofail ? ".wants/" : ".requires/", automount_name, NULL); + if (!lnk) + return log_oom(); + + mkdir_parents_label(lnk, 0755); + if (symlink(automount_unit, lnk) < 0) + return log_error_errno(errno, "Failed to create symlink %s: %m", lnk); + } + + return 0; +} + +static int parse_fstab(bool initrd) { + _cleanup_endmntent_ FILE *f = NULL; + const char *fstab_path; + struct mntent *me; + int r = 0; + + fstab_path = initrd ? "/sysroot/etc/fstab" : "/etc/fstab"; + f = setmntent(fstab_path, "re"); + if (!f) { + if (errno == ENOENT) + return 0; + + log_error_errno(errno, "Failed to open %s: %m", fstab_path); + return -errno; + } + + while ((me = getmntent(f))) { + _cleanup_free_ char *where = NULL, *what = NULL; + bool noauto, nofail; + int k; + + if (initrd && !mount_in_initrd(me)) + continue; + + what = fstab_node_to_udev_node(me->mnt_fsname); + if (!what) + return log_oom(); + + if (is_device_path(what) && path_is_read_only_fs("sys") > 0) { + log_info("Running in a container, ignoring fstab device entry for %s.", what); + continue; + } + + where = initrd ? strappend("/sysroot/", me->mnt_dir) : strdup(me->mnt_dir); + if (!where) + return log_oom(); + + if (is_path(where)) + path_kill_slashes(where); + + noauto = fstab_test_yes_no_option(me->mnt_opts, "noauto\0" "auto\0"); + nofail = fstab_test_yes_no_option(me->mnt_opts, "nofail\0" "fail\0"); + log_debug("Found entry what=%s where=%s type=%s nofail=%s noauto=%s", + what, where, me->mnt_type, + yes_no(noauto), yes_no(nofail)); + + if (streq(me->mnt_type, "swap")) + k = add_swap(what, me, noauto, nofail); + else { + bool automount; + const char *post; + + automount = fstab_test_option(me->mnt_opts, + "comment=systemd.automount\0" + "x-systemd.automount\0"); + if (initrd) + post = SPECIAL_INITRD_FS_TARGET; + else if (mount_is_network(me)) + post = SPECIAL_REMOTE_FS_TARGET; + else + post = SPECIAL_LOCAL_FS_TARGET; + + k = add_mount(what, + where, + me->mnt_type, + me->mnt_opts, + me->mnt_passno, + noauto, + nofail, + automount, + post, + fstab_path); + } + + if (k < 0) + r = k; + } + + return r; +} + +static int add_sysroot_mount(void) { + _cleanup_free_ char *what = NULL; + const char *opts; + int r; + + if (isempty(arg_root_what)) { + log_debug("Could not find a root= entry on the kernel command line."); + return 0; + } + + what = fstab_node_to_udev_node(arg_root_what); + if (!what) + return log_oom(); + + if (!arg_root_options) + opts = arg_root_rw > 0 ? "rw" : "ro"; + else if (arg_root_rw >= 0 || + !fstab_test_option(arg_root_options, "ro\0" "rw\0")) + opts = strjoina(arg_root_options, ",", arg_root_rw > 0 ? "rw" : "ro"); + else + opts = arg_root_options; + + log_debug("Found entry what=%s where=/sysroot type=%s", what, strna(arg_root_fstype)); + + if (is_device_path(what)) { + r = generator_write_initrd_root_device_deps(arg_dest, what); + if (r < 0) + return r; + } + + return add_mount(what, + "/sysroot", + arg_root_fstype, + opts, + is_device_path(what) ? 1 : 0, + false, + false, + false, + SPECIAL_INITRD_ROOT_FS_TARGET, + "/proc/cmdline"); +} + +static int add_sysroot_usr_mount(void) { + _cleanup_free_ char *what = NULL; + const char *opts; + + if (!arg_usr_what && !arg_usr_fstype && !arg_usr_options) + return 0; + + if (arg_root_what && !arg_usr_what) { + arg_usr_what = strdup(arg_root_what); + + if (!arg_usr_what) + return log_oom(); + } + + if (arg_root_fstype && !arg_usr_fstype) { + arg_usr_fstype = strdup(arg_root_fstype); + + if (!arg_usr_fstype) + return log_oom(); + } + + if (arg_root_options && !arg_usr_options) { + arg_usr_options = strdup(arg_root_options); + + if (!arg_usr_options) + return log_oom(); + } + + if (!arg_usr_what) + return 0; + + what = fstab_node_to_udev_node(arg_usr_what); + if (!path_is_absolute(what)) { + log_debug("Skipping entry what=%s where=/sysroot/usr type=%s", what, strna(arg_usr_fstype)); + return -1; + } + + if (!arg_usr_options) + opts = arg_root_rw > 0 ? "rw" : "ro"; + else if (!fstab_test_option(arg_usr_options, "ro\0" "rw\0")) + opts = strjoina(arg_usr_options, ",", arg_root_rw > 0 ? "rw" : "ro"); + else + opts = arg_usr_options; + + log_debug("Found entry what=%s where=/sysroot/usr type=%s", what, strna(arg_usr_fstype)); + return add_mount(what, + "/sysroot/usr", + arg_usr_fstype, + opts, + 1, + false, + false, + false, + SPECIAL_INITRD_FS_TARGET, + "/proc/cmdline"); +} + +static int parse_proc_cmdline_item(const char *key, const char *value) { + int r; + + /* root=, usr=, usrfstype= and roofstype= may occur more than once, the last + * instance should take precedence. In the case of multiple rootflags= + * or usrflags= the arguments should be concatenated */ + + if (STR_IN_SET(key, "fstab", "rd.fstab") && value) { + + r = parse_boolean(value); + if (r < 0) + log_warning("Failed to parse fstab switch %s. Ignoring.", value); + else + arg_fstab_enabled = r; + + } else if (streq(key, "root") && value) { + + if (free_and_strdup(&arg_root_what, value) < 0) + return log_oom(); + + } else if (streq(key, "rootfstype") && value) { + + if (free_and_strdup(&arg_root_fstype, value) < 0) + return log_oom(); + + } else if (streq(key, "rootflags") && value) { + char *o; + + o = arg_root_options ? + strjoin(arg_root_options, ",", value, NULL) : + strdup(value); + if (!o) + return log_oom(); + + free(arg_root_options); + arg_root_options = o; + + } else if (streq(key, "mount.usr") && value) { + + if (free_and_strdup(&arg_usr_what, value) < 0) + return log_oom(); + + } else if (streq(key, "mount.usrfstype") && value) { + + if (free_and_strdup(&arg_usr_fstype, value) < 0) + return log_oom(); + + } else if (streq(key, "mount.usrflags") && value) { + char *o; + + o = arg_usr_options ? + strjoin(arg_usr_options, ",", value, NULL) : + strdup(value); + if (!o) + return log_oom(); + + free(arg_usr_options); + arg_usr_options = o; + + } else if (streq(key, "rw") && !value) + arg_root_rw = true; + else if (streq(key, "ro") && !value) + arg_root_rw = false; + + return 0; +} + +int main(int argc, char *argv[]) { + int r = 0; + + 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); + + r = parse_proc_cmdline(parse_proc_cmdline_item); + if (r < 0) + log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m"); + + /* Always honour root= and usr= in the kernel command line if we are in an initrd */ + if (in_initrd()) { + r = add_sysroot_mount(); + if (r == 0) + r = add_sysroot_usr_mount(); + } + + /* Honour /etc/fstab only when that's enabled */ + if (arg_fstab_enabled) { + int k; + + log_debug("Parsing /etc/fstab"); + + /* Parse the local /etc/fstab, possibly from the initrd */ + k = parse_fstab(false); + if (k < 0) + r = k; + + /* If running in the initrd also parse the /etc/fstab from the host */ + if (in_initrd()) { + log_debug("Parsing /sysroot/etc/fstab"); + + k = parse_fstab(true); + if (k < 0) + r = k; + } + } + + free(arg_root_what); + free(arg_root_fstype); + free(arg_root_options); + + free(arg_usr_what); + free(arg_usr_fstype); + free(arg_usr_options); + + return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; +} |