diff options
Diffstat (limited to 'src/systemd-sysusers')
-rw-r--r-- | src/systemd-sysusers/Makefile | 61 | ||||
-rw-r--r-- | src/systemd-sysusers/sysusers.c | 1919 |
2 files changed, 1980 insertions, 0 deletions
diff --git a/src/systemd-sysusers/Makefile b/src/systemd-sysusers/Makefile new file mode 100644 index 0000000000..c9aaad0369 --- /dev/null +++ b/src/systemd-sysusers/Makefile @@ -0,0 +1,61 @@ +# -*- Mode: makefile; indent-tabs-mode: t -*- +# +# This file is part of systemd. +# +# Copyright 2010-2012 Lennart Poettering +# Copyright 2010-2012 Kay Sievers +# Copyright 2013 Zbigniew Jędrzejewski-Szmek +# Copyright 2013 David Strauss +# Copyright 2016 Luke Shumaker +# +# 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 $(dir $(lastword $(MAKEFILE_LIST)))/../../config.mk +include $(topsrcdir)/build-aux/Makefile.head.mk + +ifneq ($(ENABLE_SYSUSERS),) +systemd_sysusers_SOURCES = \ + src/sysusers/sysusers.c + +systemd_sysusers_LDADD = \ + libshared.la + +bin_PROGRAMS += \ + systemd-sysusers + +nodist_systemunit_DATA += \ + units/systemd-sysusers.service + +SYSINIT_TARGET_WANTS += \ + systemd-sysusers.service + +nodist_sysusers_DATA = \ + sysusers.d/systemd.conf \ + sysusers.d/basic.conf + +ifneq ($(HAVE_REMOTE),) +nodist_sysusers_DATA += \ + sysusers.d/systemd-remote.conf +endif # HAVE_REMOTE + +INSTALL_DIRS += \ + $(sysusersdir) +endif # ENABLE_SYSUSERS + +EXTRA_DIST += \ + units/systemd-sysusers.service.in \ + sysusers.d/systemd.conf.m4 \ + sysusers.d/systemd-remote.conf.m4 \ + sysusers.d/basic.conf.in + +include $(topsrcdir)/build-aux/Makefile.tail.mk diff --git a/src/systemd-sysusers/sysusers.c b/src/systemd-sysusers/sysusers.c new file mode 100644 index 0000000000..4377f1b910 --- /dev/null +++ b/src/systemd-sysusers/sysusers.c @@ -0,0 +1,1919 @@ +/*** + This file is part of systemd. + + Copyright 2014 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 <getopt.h> +#include <grp.h> +#include <gshadow.h> +#include <pwd.h> +#include <shadow.h> +#include <utmp.h> + +#include "alloc-util.h" +#include "conf-files.h" +#include "copy.h" +#include "def.h" +#include "fd-util.h" +#include "fileio-label.h" +#include "formats-util.h" +#include "hashmap.h" +#include "path-util.h" +#include "selinux-util.h" +#include "smack-util.h" +#include "specifier.h" +#include "string-util.h" +#include "strv.h" +#include "uid-range.h" +#include "user-util.h" +#include "utf8.h" +#include "util.h" + +typedef enum ItemType { + ADD_USER = 'u', + ADD_GROUP = 'g', + ADD_MEMBER = 'm', + ADD_RANGE = 'r', +} ItemType; +typedef struct Item { + ItemType type; + + char *name; + char *uid_path; + char *gid_path; + char *description; + char *home; + + gid_t gid; + uid_t uid; + + bool gid_set:1; + bool uid_set:1; + + bool todo_user:1; + bool todo_group:1; +} Item; + +static char *arg_root = NULL; + +static const char conf_file_dirs[] = CONF_PATHS_NULSTR("sysusers.d"); + +static Hashmap *users = NULL, *groups = NULL; +static Hashmap *todo_uids = NULL, *todo_gids = NULL; +static Hashmap *members = NULL; + +static Hashmap *database_uid = NULL, *database_user = NULL; +static Hashmap *database_gid = NULL, *database_group = NULL; + +static uid_t search_uid = UID_INVALID; +static UidRange *uid_range = NULL; +static unsigned n_uid_range = 0; + +static int load_user_database(void) { + _cleanup_fclose_ FILE *f = NULL; + const char *passwd_path; + struct passwd *pw; + int r; + + passwd_path = prefix_roota(arg_root, "/etc/passwd"); + f = fopen(passwd_path, "re"); + if (!f) + return errno == ENOENT ? 0 : -errno; + + r = hashmap_ensure_allocated(&database_user, &string_hash_ops); + if (r < 0) + return r; + + r = hashmap_ensure_allocated(&database_uid, NULL); + if (r < 0) + return r; + + errno = 0; + while ((pw = fgetpwent(f))) { + char *n; + int k, q; + + n = strdup(pw->pw_name); + if (!n) + return -ENOMEM; + + k = hashmap_put(database_user, n, UID_TO_PTR(pw->pw_uid)); + if (k < 0 && k != -EEXIST) { + free(n); + return k; + } + + q = hashmap_put(database_uid, UID_TO_PTR(pw->pw_uid), n); + if (q < 0 && q != -EEXIST) { + if (k < 0) + free(n); + return q; + } + + if (q < 0 && k < 0) + free(n); + + errno = 0; + } + if (!IN_SET(errno, 0, ENOENT)) + return -errno; + + return 0; +} + +static int load_group_database(void) { + _cleanup_fclose_ FILE *f = NULL; + const char *group_path; + struct group *gr; + int r; + + group_path = prefix_roota(arg_root, "/etc/group"); + f = fopen(group_path, "re"); + if (!f) + return errno == ENOENT ? 0 : -errno; + + r = hashmap_ensure_allocated(&database_group, &string_hash_ops); + if (r < 0) + return r; + + r = hashmap_ensure_allocated(&database_gid, NULL); + if (r < 0) + return r; + + errno = 0; + while ((gr = fgetgrent(f))) { + char *n; + int k, q; + + n = strdup(gr->gr_name); + if (!n) + return -ENOMEM; + + k = hashmap_put(database_group, n, GID_TO_PTR(gr->gr_gid)); + if (k < 0 && k != -EEXIST) { + free(n); + return k; + } + + q = hashmap_put(database_gid, GID_TO_PTR(gr->gr_gid), n); + if (q < 0 && q != -EEXIST) { + if (k < 0) + free(n); + return q; + } + + if (q < 0 && k < 0) + free(n); + + errno = 0; + } + if (!IN_SET(errno, 0, ENOENT)) + return -errno; + + return 0; +} + +static int make_backup(const char *target, const char *x) { + _cleanup_close_ int src = -1; + _cleanup_fclose_ FILE *dst = NULL; + char *backup, *temp; + struct timespec ts[2]; + struct stat st; + int r; + + src = open(x, O_RDONLY|O_CLOEXEC|O_NOCTTY); + if (src < 0) { + if (errno == ENOENT) /* No backup necessary... */ + return 0; + + return -errno; + } + + if (fstat(src, &st) < 0) + return -errno; + + r = fopen_temporary_label(target, x, &dst, &temp); + if (r < 0) + return r; + + r = copy_bytes(src, fileno(dst), (uint64_t) -1, true); + if (r < 0) + goto fail; + + /* Don't fail on chmod() or chown(). If it stays owned by us + * and/or unreadable by others, then it isn't too bad... */ + + backup = strjoina(x, "-"); + + /* Copy over the access mask */ + if (fchmod(fileno(dst), st.st_mode & 07777) < 0) + log_warning_errno(errno, "Failed to change mode on %s: %m", backup); + + if (fchown(fileno(dst), st.st_uid, st.st_gid)< 0) + log_warning_errno(errno, "Failed to change ownership of %s: %m", backup); + + ts[0] = st.st_atim; + ts[1] = st.st_mtim; + if (futimens(fileno(dst), ts) < 0) + log_warning_errno(errno, "Failed to fix access and modification time of %s: %m", backup); + + if (rename(temp, backup) < 0) + goto fail; + + return 0; + +fail: + unlink(temp); + return r; +} + +static int putgrent_with_members(const struct group *gr, FILE *group) { + char **a; + + assert(gr); + assert(group); + + a = hashmap_get(members, gr->gr_name); + if (a) { + _cleanup_strv_free_ char **l = NULL; + bool added = false; + char **i; + + l = strv_copy(gr->gr_mem); + if (!l) + return -ENOMEM; + + STRV_FOREACH(i, a) { + if (strv_find(l, *i)) + continue; + + if (strv_extend(&l, *i) < 0) + return -ENOMEM; + + added = true; + } + + if (added) { + struct group t; + + strv_uniq(l); + strv_sort(l); + + t = *gr; + t.gr_mem = l; + + errno = 0; + if (putgrent(&t, group) != 0) + return errno > 0 ? -errno : -EIO; + + return 1; + } + } + + errno = 0; + if (putgrent(gr, group) != 0) + return errno > 0 ? -errno : -EIO; + + return 0; +} + +static int putsgent_with_members(const struct sgrp *sg, FILE *gshadow) { + char **a; + + assert(sg); + assert(gshadow); + + a = hashmap_get(members, sg->sg_namp); + if (a) { + _cleanup_strv_free_ char **l = NULL; + bool added = false; + char **i; + + l = strv_copy(sg->sg_mem); + if (!l) + return -ENOMEM; + + STRV_FOREACH(i, a) { + if (strv_find(l, *i)) + continue; + + if (strv_extend(&l, *i) < 0) + return -ENOMEM; + + added = true; + } + + if (added) { + struct sgrp t; + + strv_uniq(l); + strv_sort(l); + + t = *sg; + t.sg_mem = l; + + errno = 0; + if (putsgent(&t, gshadow) != 0) + return errno > 0 ? -errno : -EIO; + + return 1; + } + } + + errno = 0; + if (putsgent(sg, gshadow) != 0) + return errno > 0 ? -errno : -EIO; + + return 0; +} + +static int sync_rights(FILE *from, FILE *to) { + struct stat st; + + if (fstat(fileno(from), &st) < 0) + return -errno; + + if (fchmod(fileno(to), st.st_mode & 07777) < 0) + return -errno; + + if (fchown(fileno(to), st.st_uid, st.st_gid) < 0) + return -errno; + + return 0; +} + +static int rename_and_apply_smack(const char *temp_path, const char *dest_path) { + int r = 0; + if (rename(temp_path, dest_path) < 0) + return -errno; + +#ifdef SMACK_RUN_LABEL + r = mac_smack_apply(dest_path, SMACK_ATTR_ACCESS, SMACK_FLOOR_LABEL); + if (r < 0) + return r; +#endif + return r; +} + +static int write_files(void) { + + _cleanup_fclose_ FILE *passwd = NULL, *group = NULL, *shadow = NULL, *gshadow = NULL; + _cleanup_free_ char *passwd_tmp = NULL, *group_tmp = NULL, *shadow_tmp = NULL, *gshadow_tmp = NULL; + const char *passwd_path = NULL, *group_path = NULL, *shadow_path = NULL, *gshadow_path = NULL; + bool group_changed = false; + Iterator iterator; + Item *i; + int r; + + if (hashmap_size(todo_gids) > 0 || hashmap_size(members) > 0) { + _cleanup_fclose_ FILE *original = NULL; + + /* First we update the actual group list file */ + group_path = prefix_roota(arg_root, "/etc/group"); + r = fopen_temporary_label("/etc/group", group_path, &group, &group_tmp); + if (r < 0) + goto finish; + + original = fopen(group_path, "re"); + if (original) { + struct group *gr; + + r = sync_rights(original, group); + if (r < 0) + goto finish; + + errno = 0; + while ((gr = fgetgrent(original))) { + /* Safety checks against name and GID + * collisions. Normally, this should + * be unnecessary, but given that we + * look at the entries anyway here, + * let's make an extra verification + * step that we don't generate + * duplicate entries. */ + + i = hashmap_get(groups, gr->gr_name); + if (i && i->todo_group) { + log_error("%s: Group \"%s\" already exists.", group_path, gr->gr_name); + r = -EEXIST; + goto finish; + } + + if (hashmap_contains(todo_gids, GID_TO_PTR(gr->gr_gid))) { + log_error("%s: Detected collision for GID " GID_FMT ".", group_path, gr->gr_gid); + r = -EEXIST; + goto finish; + } + + r = putgrent_with_members(gr, group); + if (r < 0) + goto finish; + if (r > 0) + group_changed = true; + + errno = 0; + } + if (!IN_SET(errno, 0, ENOENT)) { + r = -errno; + goto finish; + } + + } else if (errno != ENOENT) { + r = -errno; + goto finish; + } else if (fchmod(fileno(group), 0644) < 0) { + r = -errno; + goto finish; + } + + HASHMAP_FOREACH(i, todo_gids, iterator) { + struct group n = { + .gr_name = i->name, + .gr_gid = i->gid, + .gr_passwd = (char*) "x", + }; + + r = putgrent_with_members(&n, group); + if (r < 0) + goto finish; + + group_changed = true; + } + + r = fflush_and_check(group); + if (r < 0) + goto finish; + + if (original) { + fclose(original); + original = NULL; + } + + /* OK, now also update the shadow file for the group list */ + gshadow_path = prefix_roota(arg_root, "/etc/gshadow"); + r = fopen_temporary_label("/etc/gshadow", gshadow_path, &gshadow, &gshadow_tmp); + if (r < 0) + goto finish; + + original = fopen(gshadow_path, "re"); + if (original) { + struct sgrp *sg; + + r = sync_rights(original, gshadow); + if (r < 0) + goto finish; + + errno = 0; + while ((sg = fgetsgent(original))) { + + i = hashmap_get(groups, sg->sg_namp); + if (i && i->todo_group) { + log_error("%s: Group \"%s\" already exists.", gshadow_path, sg->sg_namp); + r = -EEXIST; + goto finish; + } + + r = putsgent_with_members(sg, gshadow); + if (r < 0) + goto finish; + if (r > 0) + group_changed = true; + + errno = 0; + } + if (!IN_SET(errno, 0, ENOENT)) { + r = -errno; + goto finish; + } + + } else if (errno != ENOENT) { + r = -errno; + goto finish; + } else if (fchmod(fileno(gshadow), 0000) < 0) { + r = -errno; + goto finish; + } + + HASHMAP_FOREACH(i, todo_gids, iterator) { + struct sgrp n = { + .sg_namp = i->name, + .sg_passwd = (char*) "!!", + }; + + r = putsgent_with_members(&n, gshadow); + if (r < 0) + goto finish; + + group_changed = true; + } + + r = fflush_and_check(gshadow); + if (r < 0) + goto finish; + } + + if (hashmap_size(todo_uids) > 0) { + _cleanup_fclose_ FILE *original = NULL; + long lstchg; + + /* First we update the user database itself */ + passwd_path = prefix_roota(arg_root, "/etc/passwd"); + r = fopen_temporary_label("/etc/passwd", passwd_path, &passwd, &passwd_tmp); + if (r < 0) + goto finish; + + original = fopen(passwd_path, "re"); + if (original) { + struct passwd *pw; + + r = sync_rights(original, passwd); + if (r < 0) + goto finish; + + errno = 0; + while ((pw = fgetpwent(original))) { + + i = hashmap_get(users, pw->pw_name); + if (i && i->todo_user) { + log_error("%s: User \"%s\" already exists.", passwd_path, pw->pw_name); + r = -EEXIST; + goto finish; + } + + if (hashmap_contains(todo_uids, UID_TO_PTR(pw->pw_uid))) { + log_error("%s: Detected collision for UID " UID_FMT ".", passwd_path, pw->pw_uid); + r = -EEXIST; + goto finish; + } + + errno = 0; + if (putpwent(pw, passwd) < 0) { + r = errno ? -errno : -EIO; + goto finish; + } + + errno = 0; + } + if (!IN_SET(errno, 0, ENOENT)) { + r = -errno; + goto finish; + } + + } else if (errno != ENOENT) { + r = -errno; + goto finish; + } else if (fchmod(fileno(passwd), 0644) < 0) { + r = -errno; + goto finish; + } + + HASHMAP_FOREACH(i, todo_uids, iterator) { + struct passwd n = { + .pw_name = i->name, + .pw_uid = i->uid, + .pw_gid = i->gid, + .pw_gecos = i->description, + + /* "x" means the password is stored in + * the shadow file */ + .pw_passwd = (char*) "x", + + /* We default to the root directory as home */ + .pw_dir = i->home ? i->home : (char*) "/", + + /* Initialize the shell to nologin, + * with one exception: for root we + * patch in something special */ + .pw_shell = i->uid == 0 ? (char*) "/bin/sh" : (char*) "/sbin/nologin", + }; + + errno = 0; + if (putpwent(&n, passwd) != 0) { + r = errno ? -errno : -EIO; + goto finish; + } + } + + r = fflush_and_check(passwd); + if (r < 0) + goto finish; + + if (original) { + fclose(original); + original = NULL; + } + + /* The we update the shadow database */ + shadow_path = prefix_roota(arg_root, "/etc/shadow"); + r = fopen_temporary_label("/etc/shadow", shadow_path, &shadow, &shadow_tmp); + if (r < 0) + goto finish; + + lstchg = (long) (now(CLOCK_REALTIME) / USEC_PER_DAY); + + original = fopen(shadow_path, "re"); + if (original) { + struct spwd *sp; + + r = sync_rights(original, shadow); + if (r < 0) + goto finish; + + errno = 0; + while ((sp = fgetspent(original))) { + + i = hashmap_get(users, sp->sp_namp); + if (i && i->todo_user) { + /* we will update the existing entry */ + sp->sp_lstchg = lstchg; + + /* only the /etc/shadow stage is left, so we can + * safely remove the item from the todo set */ + i->todo_user = false; + hashmap_remove(todo_uids, UID_TO_PTR(i->uid)); + } + + errno = 0; + if (putspent(sp, shadow) < 0) { + r = errno ? -errno : -EIO; + goto finish; + } + + errno = 0; + } + if (!IN_SET(errno, 0, ENOENT)) { + r = -errno; + goto finish; + } + } else if (errno != ENOENT) { + r = -errno; + goto finish; + } else if (fchmod(fileno(shadow), 0000) < 0) { + r = -errno; + goto finish; + } + + HASHMAP_FOREACH(i, todo_uids, iterator) { + struct spwd n = { + .sp_namp = i->name, + .sp_pwdp = (char*) "!!", + .sp_lstchg = lstchg, + .sp_min = -1, + .sp_max = -1, + .sp_warn = -1, + .sp_inact = -1, + .sp_expire = -1, + .sp_flag = (unsigned long) -1, /* this appears to be what everybody does ... */ + }; + + errno = 0; + if (putspent(&n, shadow) != 0) { + r = errno ? -errno : -EIO; + goto finish; + } + } + + r = fflush_and_check(shadow); + if (r < 0) + goto finish; + } + + /* Make a backup of the old files */ + if (group_changed) { + if (group) { + r = make_backup("/etc/group", group_path); + if (r < 0) + goto finish; + } + if (gshadow) { + r = make_backup("/etc/gshadow", gshadow_path); + if (r < 0) + goto finish; + } + } + + if (passwd) { + r = make_backup("/etc/passwd", passwd_path); + if (r < 0) + goto finish; + } + if (shadow) { + r = make_backup("/etc/shadow", shadow_path); + if (r < 0) + goto finish; + } + + /* And make the new files count */ + if (group_changed) { + if (group) { + r = rename_and_apply_smack(group_tmp, group_path); + if (r < 0) + goto finish; + + group_tmp = mfree(group_tmp); + } + if (gshadow) { + r = rename_and_apply_smack(gshadow_tmp, gshadow_path); + if (r < 0) + goto finish; + + gshadow_tmp = mfree(gshadow_tmp); + } + } + + if (passwd) { + r = rename_and_apply_smack(passwd_tmp, passwd_path); + if (r < 0) + goto finish; + + passwd_tmp = mfree(passwd_tmp); + } + if (shadow) { + r = rename_and_apply_smack(shadow_tmp, shadow_path); + if (r < 0) + goto finish; + + shadow_tmp = mfree(shadow_tmp); + } + + r = 0; + +finish: + if (passwd_tmp) + unlink(passwd_tmp); + if (shadow_tmp) + unlink(shadow_tmp); + if (group_tmp) + unlink(group_tmp); + if (gshadow_tmp) + unlink(gshadow_tmp); + + return r; +} + +static int uid_is_ok(uid_t uid, const char *name) { + struct passwd *p; + struct group *g; + const char *n; + Item *i; + + /* Let's see if we already have assigned the UID a second time */ + if (hashmap_get(todo_uids, UID_TO_PTR(uid))) + return 0; + + /* Try to avoid using uids that are already used by a group + * that doesn't have the same name as our new user. */ + i = hashmap_get(todo_gids, GID_TO_PTR(uid)); + if (i && !streq(i->name, name)) + return 0; + + /* Let's check the files directly */ + if (hashmap_contains(database_uid, UID_TO_PTR(uid))) + return 0; + + n = hashmap_get(database_gid, GID_TO_PTR(uid)); + if (n && !streq(n, name)) + return 0; + + /* Let's also check via NSS, to avoid UID clashes over LDAP and such, just in case */ + if (!arg_root) { + errno = 0; + p = getpwuid(uid); + if (p) + return 0; + if (!IN_SET(errno, 0, ENOENT)) + return -errno; + + errno = 0; + g = getgrgid((gid_t) uid); + if (g) { + if (!streq(g->gr_name, name)) + return 0; + } else if (!IN_SET(errno, 0, ENOENT)) + return -errno; + } + + return 1; +} + +static int root_stat(const char *p, struct stat *st) { + const char *fix; + + fix = prefix_roota(arg_root, p); + if (stat(fix, st) < 0) + return -errno; + + return 0; +} + +static int read_id_from_file(Item *i, uid_t *_uid, gid_t *_gid) { + struct stat st; + bool found_uid = false, found_gid = false; + uid_t uid = 0; + gid_t gid = 0; + + assert(i); + + /* First, try to get the gid directly */ + if (_gid && i->gid_path && root_stat(i->gid_path, &st) >= 0) { + gid = st.st_gid; + found_gid = true; + } + + /* Then, try to get the uid directly */ + if ((_uid || (_gid && !found_gid)) + && i->uid_path + && root_stat(i->uid_path, &st) >= 0) { + + uid = st.st_uid; + found_uid = true; + + /* If we need the gid, but had no success yet, also derive it from the uid path */ + if (_gid && !found_gid) { + gid = st.st_gid; + found_gid = true; + } + } + + /* If that didn't work yet, then let's reuse the gid as uid */ + if (_uid && !found_uid && i->gid_path) { + + if (found_gid) { + uid = (uid_t) gid; + found_uid = true; + } else if (root_stat(i->gid_path, &st) >= 0) { + uid = (uid_t) st.st_gid; + found_uid = true; + } + } + + if (_uid) { + if (!found_uid) + return 0; + + *_uid = uid; + } + + if (_gid) { + if (!found_gid) + return 0; + + *_gid = gid; + } + + return 1; +} + +static int add_user(Item *i) { + void *z; + int r; + + assert(i); + + /* Check the database directly */ + z = hashmap_get(database_user, i->name); + if (z) { + log_debug("User %s already exists.", i->name); + i->uid = PTR_TO_UID(z); + i->uid_set = true; + return 0; + } + + if (!arg_root) { + struct passwd *p; + + /* Also check NSS */ + errno = 0; + p = getpwnam(i->name); + if (p) { + log_debug("User %s already exists.", i->name); + i->uid = p->pw_uid; + i->uid_set = true; + + r = free_and_strdup(&i->description, p->pw_gecos); + if (r < 0) + return log_oom(); + + return 0; + } + if (!IN_SET(errno, 0, ENOENT)) + return log_error_errno(errno, "Failed to check if user %s already exists: %m", i->name); + } + + /* Try to use the suggested numeric uid */ + if (i->uid_set) { + r = uid_is_ok(i->uid, i->name); + if (r < 0) + return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid); + if (r == 0) { + log_debug("Suggested user ID " UID_FMT " for %s already used.", i->uid, i->name); + i->uid_set = false; + } + } + + /* If that didn't work, try to read it from the specified path */ + if (!i->uid_set) { + uid_t c; + + if (read_id_from_file(i, &c, NULL) > 0) { + + if (c <= 0 || !uid_range_contains(uid_range, n_uid_range, c)) + log_debug("User ID " UID_FMT " of file not suitable for %s.", c, i->name); + else { + r = uid_is_ok(c, i->name); + if (r < 0) + return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid); + else if (r > 0) { + i->uid = c; + i->uid_set = true; + } else + log_debug("User ID " UID_FMT " of file for %s is already used.", c, i->name); + } + } + } + + /* Otherwise, try to reuse the group ID */ + if (!i->uid_set && i->gid_set) { + r = uid_is_ok((uid_t) i->gid, i->name); + if (r < 0) + return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid); + if (r > 0) { + i->uid = (uid_t) i->gid; + i->uid_set = true; + } + } + + /* And if that didn't work either, let's try to find a free one */ + if (!i->uid_set) { + for (;;) { + r = uid_range_next_lower(uid_range, n_uid_range, &search_uid); + if (r < 0) { + log_error("No free user ID available for %s.", i->name); + return r; + } + + r = uid_is_ok(search_uid, i->name); + if (r < 0) + return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid); + else if (r > 0) + break; + } + + i->uid_set = true; + i->uid = search_uid; + } + + r = hashmap_ensure_allocated(&todo_uids, NULL); + if (r < 0) + return log_oom(); + + r = hashmap_put(todo_uids, UID_TO_PTR(i->uid), i); + if (r < 0) + return log_oom(); + + i->todo_user = true; + log_info("Creating user %s (%s) with uid " UID_FMT " and gid " GID_FMT ".", i->name, strna(i->description), i->uid, i->gid); + + return 0; +} + +static int gid_is_ok(gid_t gid) { + struct group *g; + struct passwd *p; + + if (hashmap_get(todo_gids, GID_TO_PTR(gid))) + return 0; + + /* Avoid reusing gids that are already used by a different user */ + if (hashmap_get(todo_uids, UID_TO_PTR(gid))) + return 0; + + if (hashmap_contains(database_gid, GID_TO_PTR(gid))) + return 0; + + if (hashmap_contains(database_uid, UID_TO_PTR(gid))) + return 0; + + if (!arg_root) { + errno = 0; + g = getgrgid(gid); + if (g) + return 0; + if (!IN_SET(errno, 0, ENOENT)) + return -errno; + + errno = 0; + p = getpwuid((uid_t) gid); + if (p) + return 0; + if (!IN_SET(errno, 0, ENOENT)) + return -errno; + } + + return 1; +} + +static int add_group(Item *i) { + void *z; + int r; + + assert(i); + + /* Check the database directly */ + z = hashmap_get(database_group, i->name); + if (z) { + log_debug("Group %s already exists.", i->name); + i->gid = PTR_TO_GID(z); + i->gid_set = true; + return 0; + } + + /* Also check NSS */ + if (!arg_root) { + struct group *g; + + errno = 0; + g = getgrnam(i->name); + if (g) { + log_debug("Group %s already exists.", i->name); + i->gid = g->gr_gid; + i->gid_set = true; + return 0; + } + if (!IN_SET(errno, 0, ENOENT)) + return log_error_errno(errno, "Failed to check if group %s already exists: %m", i->name); + } + + /* Try to use the suggested numeric gid */ + if (i->gid_set) { + r = gid_is_ok(i->gid); + if (r < 0) + return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid); + if (r == 0) { + log_debug("Suggested group ID " GID_FMT " for %s already used.", i->gid, i->name); + i->gid_set = false; + } + } + + /* Try to reuse the numeric uid, if there's one */ + if (!i->gid_set && i->uid_set) { + r = gid_is_ok((gid_t) i->uid); + if (r < 0) + return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid); + if (r > 0) { + i->gid = (gid_t) i->uid; + i->gid_set = true; + } + } + + /* If that didn't work, try to read it from the specified path */ + if (!i->gid_set) { + gid_t c; + + if (read_id_from_file(i, NULL, &c) > 0) { + + if (c <= 0 || !uid_range_contains(uid_range, n_uid_range, c)) + log_debug("Group ID " GID_FMT " of file not suitable for %s.", c, i->name); + else { + r = gid_is_ok(c); + if (r < 0) + return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid); + else if (r > 0) { + i->gid = c; + i->gid_set = true; + } else + log_debug("Group ID " GID_FMT " of file for %s already used.", c, i->name); + } + } + } + + /* And if that didn't work either, let's try to find a free one */ + if (!i->gid_set) { + for (;;) { + /* We look for new GIDs in the UID pool! */ + r = uid_range_next_lower(uid_range, n_uid_range, &search_uid); + if (r < 0) { + log_error("No free group ID available for %s.", i->name); + return r; + } + + r = gid_is_ok(search_uid); + if (r < 0) + return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid); + else if (r > 0) + break; + } + + i->gid_set = true; + i->gid = search_uid; + } + + r = hashmap_ensure_allocated(&todo_gids, NULL); + if (r < 0) + return log_oom(); + + r = hashmap_put(todo_gids, GID_TO_PTR(i->gid), i); + if (r < 0) + return log_oom(); + + i->todo_group = true; + log_info("Creating group %s with gid " GID_FMT ".", i->name, i->gid); + + return 0; +} + +static int process_item(Item *i) { + int r; + + assert(i); + + switch (i->type) { + + case ADD_USER: + r = add_group(i); + if (r < 0) + return r; + + return add_user(i); + + case ADD_GROUP: { + Item *j; + + j = hashmap_get(users, i->name); + if (j) { + /* There's already user to be created for this + * name, let's process that in one step */ + + if (i->gid_set) { + j->gid = i->gid; + j->gid_set = true; + } + + if (i->gid_path) { + r = free_and_strdup(&j->gid_path, i->gid_path); + if (r < 0) + return log_oom(); + } + + return 0; + } + + return add_group(i); + } + + default: + assert_not_reached("Unknown item type"); + } +} + +static void item_free(Item *i) { + + if (!i) + return; + + free(i->name); + free(i->uid_path); + free(i->gid_path); + free(i->description); + free(i); +} + +DEFINE_TRIVIAL_CLEANUP_FUNC(Item*, item_free); + +static int add_implicit(void) { + char *g, **l; + Iterator iterator; + int r; + + /* Implicitly create additional users and groups, if they were listed in "m" lines */ + + HASHMAP_FOREACH_KEY(l, g, members, iterator) { + Item *i; + char **m; + + i = hashmap_get(groups, g); + if (!i) { + _cleanup_(item_freep) Item *j = NULL; + + r = hashmap_ensure_allocated(&groups, &string_hash_ops); + if (r < 0) + return log_oom(); + + j = new0(Item, 1); + if (!j) + return log_oom(); + + j->type = ADD_GROUP; + j->name = strdup(g); + if (!j->name) + return log_oom(); + + r = hashmap_put(groups, j->name, j); + if (r < 0) + return log_oom(); + + log_debug("Adding implicit group '%s' due to m line", j->name); + j = NULL; + } + + STRV_FOREACH(m, l) { + + i = hashmap_get(users, *m); + if (!i) { + _cleanup_(item_freep) Item *j = NULL; + + r = hashmap_ensure_allocated(&users, &string_hash_ops); + if (r < 0) + return log_oom(); + + j = new0(Item, 1); + if (!j) + return log_oom(); + + j->type = ADD_USER; + j->name = strdup(*m); + if (!j->name) + return log_oom(); + + r = hashmap_put(users, j->name, j); + if (r < 0) + return log_oom(); + + log_debug("Adding implicit user '%s' due to m line", j->name); + j = NULL; + } + } + } + + return 0; +} + +static bool item_equal(Item *a, Item *b) { + assert(a); + assert(b); + + if (a->type != b->type) + return false; + + if (!streq_ptr(a->name, b->name)) + return false; + + if (!streq_ptr(a->uid_path, b->uid_path)) + return false; + + if (!streq_ptr(a->gid_path, b->gid_path)) + return false; + + if (!streq_ptr(a->description, b->description)) + return false; + + if (a->uid_set != b->uid_set) + return false; + + if (a->uid_set && a->uid != b->uid) + return false; + + if (a->gid_set != b->gid_set) + return false; + + if (a->gid_set && a->gid != b->gid) + return false; + + if (!streq_ptr(a->home, b->home)) + return false; + + return true; +} + +static bool valid_user_group_name(const char *u) { + const char *i; + long sz; + + if (isempty(u)) + return false; + + if (!(u[0] >= 'a' && u[0] <= 'z') && + !(u[0] >= 'A' && u[0] <= 'Z') && + u[0] != '_') + return false; + + for (i = u+1; *i; i++) { + if (!(*i >= 'a' && *i <= 'z') && + !(*i >= 'A' && *i <= 'Z') && + !(*i >= '0' && *i <= '9') && + *i != '_' && + *i != '-') + return false; + } + + sz = sysconf(_SC_LOGIN_NAME_MAX); + assert_se(sz > 0); + + if ((size_t) (i-u) > (size_t) sz) + return false; + + if ((size_t) (i-u) > UT_NAMESIZE - 1) + return false; + + return true; +} + +static bool valid_gecos(const char *d) { + + if (!d) + return false; + + if (!utf8_is_valid(d)) + return false; + + if (string_has_cc(d, NULL)) + return false; + + /* Colons are used as field separators, and hence not OK */ + if (strchr(d, ':')) + return false; + + return true; +} + +static bool valid_home(const char *p) { + + if (isempty(p)) + return false; + + if (!utf8_is_valid(p)) + return false; + + if (string_has_cc(p, NULL)) + return false; + + if (!path_is_absolute(p)) + return false; + + if (!path_is_safe(p)) + return false; + + /* Colons are used as field separators, and hence not OK */ + if (strchr(p, ':')) + return false; + + return true; +} + +static int parse_line(const char *fname, unsigned line, const char *buffer) { + + static const Specifier specifier_table[] = { + { 'm', specifier_machine_id, NULL }, + { 'b', specifier_boot_id, NULL }, + { 'H', specifier_host_name, NULL }, + { 'v', specifier_kernel_release, NULL }, + {} + }; + + _cleanup_free_ char *action = NULL, *name = NULL, *id = NULL, *resolved_name = NULL, *resolved_id = NULL, *description = NULL, *home = NULL; + _cleanup_(item_freep) Item *i = NULL; + Item *existing; + Hashmap *h; + int r; + const char *p; + + assert(fname); + assert(line >= 1); + assert(buffer); + + /* Parse columns */ + p = buffer; + r = extract_many_words(&p, NULL, EXTRACT_QUOTES, &action, &name, &id, &description, &home, NULL); + if (r < 0) { + log_error("[%s:%u] Syntax error.", fname, line); + return r; + } + if (r < 2) { + log_error("[%s:%u] Missing action and name columns.", fname, line); + return -EINVAL; + } + if (!isempty(p)) { + log_error("[%s:%u] Trailing garbage.", fname, line); + return -EINVAL; + } + + /* Verify action */ + if (strlen(action) != 1) { + log_error("[%s:%u] Unknown modifier '%s'", fname, line, action); + return -EINVAL; + } + + if (!IN_SET(action[0], ADD_USER, ADD_GROUP, ADD_MEMBER, ADD_RANGE)) { + log_error("[%s:%u] Unknown command command type '%c'.", fname, line, action[0]); + return -EBADMSG; + } + + /* Verify name */ + if (isempty(name) || streq(name, "-")) + name = mfree(name); + + if (name) { + r = specifier_printf(name, specifier_table, NULL, &resolved_name); + if (r < 0) { + log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, name); + return r; + } + + if (!valid_user_group_name(resolved_name)) { + log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_name); + return -EINVAL; + } + } + + /* Verify id */ + if (isempty(id) || streq(id, "-")) + id = mfree(id); + + if (id) { + r = specifier_printf(id, specifier_table, NULL, &resolved_id); + if (r < 0) { + log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, name); + return r; + } + } + + /* Verify description */ + if (isempty(description) || streq(description, "-")) + description = mfree(description); + + if (description) { + if (!valid_gecos(description)) { + log_error("[%s:%u] '%s' is not a valid GECOS field.", fname, line, description); + return -EINVAL; + } + } + + /* Verify home */ + if (isempty(home) || streq(home, "-")) + home = mfree(home); + + if (home) { + if (!valid_home(home)) { + log_error("[%s:%u] '%s' is not a valid home directory field.", fname, line, home); + return -EINVAL; + } + } + + switch (action[0]) { + + case ADD_RANGE: + if (resolved_name) { + log_error("[%s:%u] Lines of type 'r' don't take a name field.", fname, line); + return -EINVAL; + } + + if (!resolved_id) { + log_error("[%s:%u] Lines of type 'r' require a ID range in the third field.", fname, line); + return -EINVAL; + } + + if (description) { + log_error("[%s:%u] Lines of type 'r' don't take a GECOS field.", fname, line); + return -EINVAL; + } + + if (home) { + log_error("[%s:%u] Lines of type 'r' don't take a home directory field.", fname, line); + return -EINVAL; + } + + r = uid_range_add_str(&uid_range, &n_uid_range, resolved_id); + if (r < 0) { + log_error("[%s:%u] Invalid UID range %s.", fname, line, resolved_id); + return -EINVAL; + } + + return 0; + + case ADD_MEMBER: { + char **l; + + /* Try to extend an existing member or group item */ + if (!name) { + log_error("[%s:%u] Lines of type 'm' require a user name in the second field.", fname, line); + return -EINVAL; + } + + if (!resolved_id) { + log_error("[%s:%u] Lines of type 'm' require a group name in the third field.", fname, line); + return -EINVAL; + } + + if (!valid_user_group_name(resolved_id)) { + log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_id); + return -EINVAL; + } + + if (description) { + log_error("[%s:%u] Lines of type 'm' don't take a GECOS field.", fname, line); + return -EINVAL; + } + + if (home) { + log_error("[%s:%u] Lines of type 'm' don't take a home directory field.", fname, line); + return -EINVAL; + } + + r = hashmap_ensure_allocated(&members, &string_hash_ops); + if (r < 0) + return log_oom(); + + l = hashmap_get(members, resolved_id); + if (l) { + /* A list for this group name already exists, let's append to it */ + r = strv_push(&l, resolved_name); + if (r < 0) + return log_oom(); + + resolved_name = NULL; + + assert_se(hashmap_update(members, resolved_id, l) >= 0); + } else { + /* No list for this group name exists yet, create one */ + + l = new0(char *, 2); + if (!l) + return -ENOMEM; + + l[0] = resolved_name; + l[1] = NULL; + + r = hashmap_put(members, resolved_id, l); + if (r < 0) { + free(l); + return log_oom(); + } + + resolved_id = resolved_name = NULL; + } + + return 0; + } + + case ADD_USER: + if (!name) { + log_error("[%s:%u] Lines of type 'u' require a user name in the second field.", fname, line); + return -EINVAL; + } + + r = hashmap_ensure_allocated(&users, &string_hash_ops); + if (r < 0) + return log_oom(); + + i = new0(Item, 1); + if (!i) + return log_oom(); + + if (resolved_id) { + if (path_is_absolute(resolved_id)) { + i->uid_path = resolved_id; + resolved_id = NULL; + + path_kill_slashes(i->uid_path); + } else { + r = parse_uid(resolved_id, &i->uid); + if (r < 0) { + log_error("Failed to parse UID: %s", id); + return -EBADMSG; + } + + i->uid_set = true; + } + } + + i->description = description; + description = NULL; + + i->home = home; + home = NULL; + + h = users; + break; + + case ADD_GROUP: + if (!name) { + log_error("[%s:%u] Lines of type 'g' require a user name in the second field.", fname, line); + return -EINVAL; + } + + if (description) { + log_error("[%s:%u] Lines of type 'g' don't take a GECOS field.", fname, line); + return -EINVAL; + } + + if (home) { + log_error("[%s:%u] Lines of type 'g' don't take a home directory field.", fname, line); + return -EINVAL; + } + + r = hashmap_ensure_allocated(&groups, &string_hash_ops); + if (r < 0) + return log_oom(); + + i = new0(Item, 1); + if (!i) + return log_oom(); + + if (resolved_id) { + if (path_is_absolute(resolved_id)) { + i->gid_path = resolved_id; + resolved_id = NULL; + + path_kill_slashes(i->gid_path); + } else { + r = parse_gid(resolved_id, &i->gid); + if (r < 0) { + log_error("Failed to parse GID: %s", id); + return -EBADMSG; + } + + i->gid_set = true; + } + } + + h = groups; + break; + + default: + return -EBADMSG; + } + + i->type = action[0]; + i->name = resolved_name; + resolved_name = NULL; + + existing = hashmap_get(h, i->name); + if (existing) { + + /* Two identical items are fine */ + if (!item_equal(existing, i)) + log_warning("Two or more conflicting lines for %s configured, ignoring.", i->name); + + return 0; + } + + r = hashmap_put(h, i->name, i); + if (r < 0) + return log_oom(); + + i = NULL; + return 0; +} + +static int read_config_file(const char *fn, bool ignore_enoent) { + _cleanup_fclose_ FILE *rf = NULL; + FILE *f = NULL; + char line[LINE_MAX]; + unsigned v = 0; + int r = 0; + + assert(fn); + + if (streq(fn, "-")) + f = stdin; + else { + r = search_and_fopen_nulstr(fn, "re", arg_root, conf_file_dirs, &rf); + if (r < 0) { + if (ignore_enoent && r == -ENOENT) + return 0; + + return log_error_errno(r, "Failed to open '%s', ignoring: %m", fn); + } + + f = rf; + } + + FOREACH_LINE(line, f, break) { + char *l; + int k; + + v++; + + l = strstrip(line); + if (*l == '#' || *l == 0) + continue; + + k = parse_line(fn, v, l); + if (k < 0 && r == 0) + r = k; + } + + if (ferror(f)) { + log_error_errno(errno, "Failed to read from file %s: %m", fn); + if (r == 0) + r = -EIO; + } + + return r; +} + +static void free_database(Hashmap *by_name, Hashmap *by_id) { + char *name; + + for (;;) { + name = hashmap_first(by_id); + if (!name) + break; + + hashmap_remove(by_name, name); + + hashmap_steal_first_key(by_id); + free(name); + } + + while ((name = hashmap_steal_first_key(by_name))) + free(name); + + hashmap_free(by_name); + hashmap_free(by_id); +} + +static void help(void) { + printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n" + "Creates system user accounts.\n\n" + " -h --help Show this help\n" + " --version Show package version\n" + " --root=PATH Operate on an alternate filesystem root\n" + , program_invocation_short_name); +} + +static int parse_argv(int argc, char *argv[]) { + + enum { + ARG_VERSION = 0x100, + ARG_ROOT, + }; + + static const struct option options[] = { + { "help", no_argument, NULL, 'h' }, + { "version", no_argument, NULL, ARG_VERSION }, + { "root", required_argument, NULL, ARG_ROOT }, + {} + }; + + int c, r; + + assert(argc >= 0); + assert(argv); + + while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) + + switch (c) { + + case 'h': + help(); + return 0; + + case ARG_VERSION: + return version(); + + case ARG_ROOT: + r = parse_path_argument_and_warn(optarg, true, &arg_root); + if (r < 0) + return r; + break; + + case '?': + return -EINVAL; + + default: + assert_not_reached("Unhandled option"); + } + + return 1; +} + +int main(int argc, char *argv[]) { + + _cleanup_close_ int lock = -1; + Iterator iterator; + int r, k; + Item *i; + char *n; + + r = parse_argv(argc, argv); + if (r <= 0) + goto finish; + + log_set_target(LOG_TARGET_AUTO); + log_parse_environment(); + log_open(); + + umask(0022); + + r = mac_selinux_init(); + if (r < 0) { + log_error_errno(r, "SELinux setup failed: %m"); + goto finish; + } + + if (optind < argc) { + int j; + + for (j = optind; j < argc; j++) { + k = read_config_file(argv[j], false); + if (k < 0 && r == 0) + r = k; + } + } else { + _cleanup_strv_free_ char **files = NULL; + char **f; + + r = conf_files_list_nulstr(&files, ".conf", arg_root, conf_file_dirs); + if (r < 0) { + log_error_errno(r, "Failed to enumerate sysusers.d files: %m"); + goto finish; + } + + STRV_FOREACH(f, files) { + k = read_config_file(*f, true); + if (k < 0 && r == 0) + r = k; + } + } + + if (!uid_range) { + /* Default to default range of 1..SYSTEMD_UID_MAX */ + r = uid_range_add(&uid_range, &n_uid_range, 1, SYSTEM_UID_MAX); + if (r < 0) { + log_oom(); + goto finish; + } + } + + r = add_implicit(); + if (r < 0) + goto finish; + + lock = take_etc_passwd_lock(arg_root); + if (lock < 0) { + log_error_errno(lock, "Failed to take lock: %m"); + goto finish; + } + + r = load_user_database(); + if (r < 0) { + log_error_errno(r, "Failed to load user database: %m"); + goto finish; + } + + r = load_group_database(); + if (r < 0) { + log_error_errno(r, "Failed to read group database: %m"); + goto finish; + } + + HASHMAP_FOREACH(i, groups, iterator) + process_item(i); + + HASHMAP_FOREACH(i, users, iterator) + process_item(i); + + r = write_files(); + if (r < 0) + log_error_errno(r, "Failed to write files: %m"); + +finish: + while ((i = hashmap_steal_first(groups))) + item_free(i); + + while ((i = hashmap_steal_first(users))) + item_free(i); + + while ((n = hashmap_first_key(members))) { + strv_free(hashmap_steal_first(members)); + free(n); + } + + hashmap_free(groups); + hashmap_free(users); + hashmap_free(members); + hashmap_free(todo_uids); + hashmap_free(todo_gids); + + free_database(database_user, database_uid); + free_database(database_group, database_gid); + + free(arg_root); + + return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS; +} |