From f5b3ded656a491b59f8c9d5ce12cee665bb5d5f5 Mon Sep 17 00:00:00 2001 From: Louis Rannou Date: Thu, 15 Jun 2023 13:43:53 +0200 Subject: rootfs-postcommands: change sysusers.d command The configuration in sysusers.d used to be parsed to create users/groups at build time instead at runtime. This was leading to several conflicts with users/groups defined in base-passwd recipe and specific definitions in recipes inheriting the useradd class. Some of those conflicts raised unseen errors in the do_rootfs command's logs. As an example, the root home directory is set by default to `/home/root` but systemd expects it as `/root`. The new command `systemd_sysusers_check` checks each configuration for users/groups and compare their properties to what is actually defined in the `/etc/passwd` and `/etc/group` of the target rootfs. (From OE-Core rev: 0c7e76df68acfeca059a6b906d2a891d56f01e77) Signed-off-by: Louis Rannou Signed-off-by: Richard Purdie --- meta/classes-recipe/rootfs-postcommands.bbclass | 133 +++++++++++++++++++----- 1 file changed, 109 insertions(+), 24 deletions(-) (limited to 'meta') diff --git a/meta/classes-recipe/rootfs-postcommands.bbclass b/meta/classes-recipe/rootfs-postcommands.bbclass index 690fa976aa..652601b95f 100644 --- a/meta/classes-recipe/rootfs-postcommands.bbclass +++ b/meta/classes-recipe/rootfs-postcommands.bbclass @@ -43,7 +43,7 @@ ROOTFS_POSTUNINSTALL_COMMAND =+ "write_image_manifest ; " POSTINST_LOGFILE ?= "${localstatedir}/log/postinstall.log" # Set default target for systemd images SYSTEMD_DEFAULT_TARGET ?= '${@bb.utils.contains_any("IMAGE_FEATURES", [ "x11-base", "weston" ], "graphical.target", "multi-user.target", d)}' -ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains("DISTRO_FEATURES", "systemd", "set_systemd_default_target; systemd_create_users;", "", d)}' +ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains("DISTRO_FEATURES", "systemd", "set_systemd_default_target; systemd_sysusers_check;", "", d)}' ROOTFS_POSTPROCESS_COMMAND += 'empty_var_volatile;' @@ -69,29 +69,114 @@ python () { d.appendVar('ROOTFS_POSTPROCESS_COMMAND', 'rootfs_reproducible;') } -systemd_create_users () { - for conffile in ${IMAGE_ROOTFS}/usr/lib/sysusers.d/*.conf; do - [ -e $conffile ] || continue - grep -v "^#" $conffile | sed -e '/^$/d' | while read type name id comment; do - if [ "$type" = "u" ]; then - useradd_params="--shell /sbin/nologin" - [ "$id" != "-" ] && useradd_params="$useradd_params --uid $id" - [ "$comment" != "-" ] && useradd_params="$useradd_params --comment $comment" - useradd_params="$useradd_params --system $name" - eval useradd --root ${IMAGE_ROOTFS} $useradd_params || true - elif [ "$type" = "g" ]; then - groupadd_params="" - [ "$id" != "-" ] && groupadd_params="$groupadd_params --gid $id" - groupadd_params="$groupadd_params --system $name" - eval groupadd --root ${IMAGE_ROOTFS} $groupadd_params || true - elif [ "$type" = "m" ]; then - group=$id - eval groupadd --root ${IMAGE_ROOTFS} --system $group || true - eval useradd --root ${IMAGE_ROOTFS} --shell /sbin/nologin --system $name --no-user-group || true - eval usermod --root ${IMAGE_ROOTFS} -a -G $group $name - fi - done - done +# Resolve the ID as described in the sysusers.d(5) manual: ID can be a numeric +# uid, a couple uid:gid or uid:groupname or it is '-' meaning leaving it +# automatic or it can be a path. In the latter, the uid/gid matches the +# user/group owner of that file. +def resolve_sysusers_id(d, sid): + # If the id is a path, the uid/gid matchs to the target's uid/gid in the + # rootfs. + if '/' in sid: + try: + osstat = os.stat(os.path.join(d.getVar('IMAGE_ROOTFS'), sid)) + except FileNotFoundError: + bb.error('sysusers.d: file %s is required but it does not exist in the rootfs', sid) + return ('-', '-') + return (osstat.st_uid, osstat.st_gid) + # Else it is a uid:gid or uid:groupname syntax + if ':' in sid: + return sid.split(':') + else: + return (sid, '-') + +# Check a user exists in the rootfs password file and return its properties +def check_user_exists(d, uname=None, uid=None): + with open(os.path.join(d.getVar('IMAGE_ROOTFS'), 'etc/passwd'), 'r') as pwfile: + for line in pwfile: + (name, _, u_id, gid, comment, homedir, ushell) = line.strip().split(':') + if uname == name or uid == u_id: + return (name, u_id, gid, comment or '-', homedir or '/', ushell or '-') + return None + +# Check a group exists in the rootfs group file and return its properties +def check_group_exists(d, gname=None, gid=None): + with open(os.path.join(d.getVar('IMAGE_ROOTFS'), 'etc/group'), 'r') as gfile: + for line in gfile: + (name, _, g_id, _) = line.strip().split(':') + if name == gname or g_id == gid: + return (name, g_id) + return None + +def compare_users(user, e_user): + # user and e_user must not have None values. Unset values must be '-'. + (name, uid, gid, comment, homedir, ushell) = user + (e_name, e_uid, e_gid, e_comment, e_homedir, e_ushell) = e_user + # Ignore 'uid', 'gid' or 'comment' if they are not set + # Ignore 'shell' and 'ushell' if one is not set + return name == e_name \ + and (uid == '-' or uid == e_uid) \ + and (gid == '-' or gid == e_gid) \ + and (comment == '-' or e_comment == '-' or comment.lower() == e_comment.lower()) \ + and (homedir == '-' or e_homedir == '-' or homedir == e_homedir) \ + and (ushell == '-' or e_ushell == '-' or ushell == e_ushell) + +# Open sysusers.d configuration files and parse each line to check the users and +# groups are already defined in /etc/passwd and /etc/groups with similar +# properties. Refer to the sysusers.d(5) manual for its syntax. +python systemd_sysusers_check() { + import glob + import re + + pattern_comment = r'(-|\"[^:\"]+\")' + pattern_word = r'[^\s]+' + pattern_line = r'(' + pattern_word + r')\s+(' + pattern_word + r')\s+(' + pattern_word + r')(\s+' \ + + pattern_comment + r')?' + r'(\s+(' + pattern_word + r'))?' + r'(\s+(' + pattern_word + r'))?' + + for conffile in glob.glob(os.path.join(d.getVar('IMAGE_ROOTFS'), 'usr/lib/sysusers.d/*.conf')): + with open(conffile, 'r') as f: + for line in f: + line = line.strip() + if not len(line) or line[0] == '#': continue + ret = re.fullmatch(pattern_line, line.strip()) + if not ret: continue + (stype, sname, sid, _, scomment, _, shomedir, _, sshell) = ret.groups() + if stype == 'u': + if sid: + (suid, sgid) = resolve_sysusers_id(d, sid) + if sgid.isalpha(): + sgid = check_group_exists(d, gname=sgid) + elif sgid.isdigit(): + check_group_exists(d, gid=sgid) + else: + sgid = '-' + else: + suid = '-' + sgid = '-' + scomment = scomment.replace('"', '') if scomment else '-' + shomedir = shomedir or '-' + sshell = sshell or '-' + e_user = check_user_exists(d, uname=sname) + if not e_user: + bb.warn('User %s has never been defined' % sname) + elif not compare_users((sname, suid, sgid, scomment, shomedir, sshell), e_user): + bb.warn('User %s has been defined as (%s) but sysusers.d expects it as (%s)' + % (sname, ', '.join(e_user), + ', '.join((sname, suid, sgid, scomment, shomedir, sshell)))) + elif stype == 'g': + gid = sid or '-' + if '/' in gid: + (_, gid) = resolve_sysusers_id(d, sid) + e_group = check_group_exists(d, gname=sname) + if not e_group: + bb.warn('Group %s has never been defined' % sname) + elif gid != '-': + (_, e_gid) = e_group + if gid != e_gid: + bb.warn('Group %s has been defined with id (%s) but sysusers.d expects gid (%s)' + % (sname, e_gid, gid)) + elif stype == 'm': + check_user_exists(d, sname) + check_group_exists(d, sid) } # -- cgit v1.2.3-54-g00ecf