Adding upstream version 252.22.upstream/252.22upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 304 insertions, 0 deletions

diff --git a/src/shared/userdb-dropin.c b/src/shared/userdb-dropin.c
new file mode 100644
index 0000000..5d79f46
--- /dev/null
+++ b/src/shared/userdb-dropin.c
@@ -0,0 +1,304 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "errno-util.h"
+#include "fd-util.h"
+#include "fileio.h"
+#include "format-util.h"
+#include "path-util.h"
+#include "stdio-util.h"
+#include "user-util.h"
+#include "userdb-dropin.h"
+
+static int load_user(
+                FILE *f,
+                const char *path,
+                const char *name,
+                uid_t uid,
+                UserDBFlags flags,
+                UserRecord **ret) {
+
+        _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
+        _cleanup_(user_record_unrefp) UserRecord *u = NULL;
+        bool have_privileged;
+        int r;
+
+        assert(f);
+
+        r = json_parse_file(f, path, 0, &v, NULL, NULL);
+        if (r < 0)
+                return r;
+
+        if (FLAGS_SET(flags, USERDB_SUPPRESS_SHADOW) || !path || !(name || uid_is_valid(uid)))
+                have_privileged = false;
+        else {
+                _cleanup_(json_variant_unrefp) JsonVariant *privileged_v = NULL;
+                _cleanup_free_ char *d = NULL, *j = NULL;
+
+                /* Let's load the "privileged" section from a companion file. But only if USERDB_AVOID_SHADOW
+                 * is not set. After all, the privileged section kinda takes the role of the data from the
+                 * shadow file, hence it makes sense to use the same flag here.
+                 *
+                 * The general assumption is that whoever provides these records makes the .user file
+                 * world-readable, but the .privilege file readable to root and the assigned UID only. But we
+                 * won't verify that here, as it would be too late. */
+
+                r = path_extract_directory(path, &d);
+                if (r < 0)
+                        return r;
+
+                if (name) {
+                        j = strjoin(d, "/", name, ".user-privileged");
+                        if (!j)
+                                return -ENOMEM;
+                } else {
+                        assert(uid_is_valid(uid));
+                        if (asprintf(&j, "%s/" UID_FMT ".user-privileged", d, uid) < 0)
+                                return -ENOMEM;
+                }
+
+                r = json_parse_file(NULL, j, JSON_PARSE_SENSITIVE, &privileged_v, NULL, NULL);
+                if (ERRNO_IS_PRIVILEGE(r))
+                        have_privileged = false;
+                else if (r == -ENOENT)
+                        have_privileged = true; /* if the privileged file doesn't exist, we are complete */
+                else if (r < 0)
+                        return r;
+                else {
+                        r = json_variant_merge(&v, privileged_v);
+                        if (r < 0)
+                                return r;
+
+                        have_privileged = true;
+                }
+        }
+
+        u = user_record_new();
+        if (!u)
+                return -ENOMEM;
+
+        r = user_record_load(
+                        u, v,
+                        USER_RECORD_REQUIRE_REGULAR|
+                        USER_RECORD_ALLOW_PER_MACHINE|
+                        USER_RECORD_ALLOW_BINDING|
+                        USER_RECORD_ALLOW_SIGNATURE|
+                        (have_privileged ? USER_RECORD_ALLOW_PRIVILEGED : 0)|
+                        USER_RECORD_PERMISSIVE);
+        if (r < 0)
+                return r;
+
+        if (name && !streq_ptr(name, u->user_name))
+                return -EINVAL;
+
+        if (uid_is_valid(uid) && uid != u->uid)
+                return -EINVAL;
+
+        u->incomplete = !have_privileged;
+
+        if (ret)
+                *ret = TAKE_PTR(u);
+
+        return 0;
+}
+
+int dropin_user_record_by_name(const char *name, const char *path, UserDBFlags flags, UserRecord **ret) {
+        _cleanup_free_ char *found_path = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        int r;
+
+        assert(name);
+
+        if (path) {
+                f = fopen(path, "re");
+                if (!f)
+                        return errno == ENOENT ? -ESRCH : -errno; /* We generally want ESRCH to indicate no such user */
+        } else {
+                const char *j;
+
+                j = strjoina(name, ".user");
+                if (!filename_is_valid(j)) /* Doesn't qualify as valid filename? Then it's definitely not provided as a drop-in */
+                        return -ESRCH;
+
+                r = search_and_fopen_nulstr(j, "re", NULL, USERDB_DROPIN_DIR_NULSTR("userdb"), &f, &found_path);
+                if (r == -ENOENT)
+                        return -ESRCH;
+                if (r < 0)
+                        return r;
+
+                path = found_path;
+        }
+
+        return load_user(f, path, name, UID_INVALID, flags, ret);
+}
+
+int dropin_user_record_by_uid(uid_t uid, const char *path, UserDBFlags flags, UserRecord **ret) {
+        _cleanup_free_ char *found_path = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        int r;
+
+        assert(uid_is_valid(uid));
+
+        if (path) {
+                f = fopen(path, "re");
+                if (!f)
+                        return errno == ENOENT ? -ESRCH : -errno;
+        } else {
+                char buf[DECIMAL_STR_MAX(uid_t) + STRLEN(".user") + 1];
+
+                xsprintf(buf, UID_FMT ".user", uid);
+                /* Note that we don't bother to validate this as a filename, as this is generated from a decimal
+                 * integer, i.e. is definitely OK as a filename */
+
+                r = search_and_fopen_nulstr(buf, "re", NULL, USERDB_DROPIN_DIR_NULSTR("userdb"), &f, &found_path);
+                if (r == -ENOENT)
+                        return -ESRCH;
+                if (r < 0)
+                        return r;
+
+                path = found_path;
+        }
+
+        return load_user(f, path, NULL, uid, flags, ret);
+}
+
+static int load_group(
+                FILE *f,
+                const char *path,
+                const char *name,
+                gid_t gid,
+                UserDBFlags flags,
+                GroupRecord **ret) {
+
+        _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
+        _cleanup_(group_record_unrefp) GroupRecord *g = NULL;
+        bool have_privileged;
+        int r;
+
+        assert(f);
+
+        r = json_parse_file(f, path, 0, &v, NULL, NULL);
+        if (r < 0)
+                return r;
+
+        if (FLAGS_SET(flags, USERDB_SUPPRESS_SHADOW) || !path || !(name || gid_is_valid(gid)))
+                have_privileged = false;
+        else {
+                _cleanup_(json_variant_unrefp) JsonVariant *privileged_v = NULL;
+                _cleanup_free_ char *d = NULL, *j = NULL;
+
+                r = path_extract_directory(path, &d);
+                if (r < 0)
+                        return r;
+
+                if (name) {
+                        j = strjoin(d, "/", name, ".group-privileged");
+                        if (!j)
+                                return -ENOMEM;
+                } else {
+                        assert(gid_is_valid(gid));
+                        if (asprintf(&j, "%s/" GID_FMT ".group-privileged", d, gid) < 0)
+                                return -ENOMEM;
+                }
+
+                r = json_parse_file(NULL, j, JSON_PARSE_SENSITIVE, &privileged_v, NULL, NULL);
+                if (ERRNO_IS_PRIVILEGE(r))
+                        have_privileged = false;
+                else if (r == -ENOENT)
+                        have_privileged = true; /* if the privileged file doesn't exist, we are complete */
+                else if (r < 0)
+                        return r;
+                else {
+                        r = json_variant_merge(&v, privileged_v);
+                        if (r < 0)
+                                return r;
+
+                        have_privileged = true;
+                }
+        }
+
+        g = group_record_new();
+        if (!g)
+                return -ENOMEM;
+
+        r = group_record_load(
+                        g, v,
+                        USER_RECORD_REQUIRE_REGULAR|
+                        USER_RECORD_ALLOW_PER_MACHINE|
+                        USER_RECORD_ALLOW_BINDING|
+                        USER_RECORD_ALLOW_SIGNATURE|
+                        (have_privileged ? USER_RECORD_ALLOW_PRIVILEGED : 0)|
+                        USER_RECORD_PERMISSIVE);
+        if (r < 0)
+                return r;
+
+        if (name && !streq_ptr(name, g->group_name))
+                return -EINVAL;
+
+        if (gid_is_valid(gid) && gid != g->gid)
+                return -EINVAL;
+
+        g->incomplete = !have_privileged;
+
+        if (ret)
+                *ret = TAKE_PTR(g);
+
+        return 0;
+}
+
+int dropin_group_record_by_name(const char *name, const char *path, UserDBFlags flags, GroupRecord **ret) {
+        _cleanup_free_ char *found_path = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        int r;
+
+        assert(name);
+
+        if (path) {
+                f = fopen(path, "re");
+                if (!f)
+                        return errno == ENOENT ? -ESRCH : -errno;
+        } else {
+                const char *j;
+
+                j = strjoina(name, ".group");
+                if (!filename_is_valid(j)) /* Doesn't qualify as valid filename? Then it's definitely not provided as a drop-in */
+                        return -ESRCH;
+
+                r = search_and_fopen_nulstr(j, "re", NULL, USERDB_DROPIN_DIR_NULSTR("userdb"), &f, &found_path);
+                if (r == -ENOENT)
+                        return -ESRCH;
+                if (r < 0)
+                        return r;
+
+                path = found_path;
+        }
+
+        return load_group(f, path, name, GID_INVALID, flags, ret);
+}
+
+int dropin_group_record_by_gid(gid_t gid, const char *path, UserDBFlags flags, GroupRecord **ret) {
+        _cleanup_free_ char *found_path = NULL;
+        _cleanup_fclose_ FILE *f = NULL;
+        int r;
+
+        assert(gid_is_valid(gid));
+
+        if (path) {
+                f = fopen(path, "re");
+                if (!f)
+                        return errno == ENOENT ? -ESRCH : -errno;
+        } else {
+                char buf[DECIMAL_STR_MAX(gid_t) + STRLEN(".group") + 1];
+
+                xsprintf(buf, GID_FMT ".group", gid);
+
+                r = search_and_fopen_nulstr(buf, "re", NULL, USERDB_DROPIN_DIR_NULSTR("userdb"), &f, &found_path);
+                if (r == -ENOENT)
+                        return -ESRCH;
+                if (r < 0)
+                        return r;
+
+                path = found_path;
+        }
+
+        return load_group(f, path, NULL, gid, flags, ret);
+}