Re: [Kimchi-devel] [PATCH V5] add a method to fix search permissions

From: ShaoHe Feng <shaohef(a)linux.vnet.ibm.com&gt; First will use setfacl to set the path search permission for user or group, if failed then set search permission for others on the path. Usage: check_path_permission("/tmp/need/to/fix/path", username) fix_path_permission("/tmp/need/to/fix/path", username) Signed-off-by: ShaoHe Feng <shaohef(a)linux.vnet.ibm.com&gt; Signed-off-by: Royce Lv <lvroyce(a)linux.vnet.ibm.com&gt; --- Makefile.am | 1 + src/kimchi/utils.py | 125 +++++++++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 125 insertions(+), 1 deletion(-) diff --git a/Makefile.am b/Makefile.am index 07b2aa0..bf8e0a0 100644 --- a/Makefile.am +++ b/Makefile.am @@ -46,6 +46,7 @@ PEP8_WHITELIST = \ src/kimchi/cachebust.py \ src/kimchi/config.py.in \ src/kimchi/control/*.py \ + src/kimchi/utils.py \ src/kimchi/disks.py \ src/kimchi/featuretests.py \ src/kimchi/iscsi.py \ diff --git a/src/kimchi/utils.py b/src/kimchi/utils.py index b6d84fd..5de982f 100644 --- a/src/kimchi/utils.py +++ b/src/kimchi/utils.py @@ -18,11 +18,16 @@ # # You should have received a copy of the GNU Lesser General Public # License along with this library; if not, write to the Free Software -# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA +# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA # import cherrypy +import grp import os +import pwd +import re +import stat +import subprocess from cherrypy.lib.reprconf import Parser @@ -33,6 +38,7 @@ from kimchi import config kimchi_log = cherrypy.log.error_log + def is_digit(value): if isinstance(value, int): return True @@ -84,3 +90,120 @@ def import_class(class_path): def import_module(module_name): return __import__(module_name, globals(), locals(), ['']) + + +def run_command(cmd): + try: + proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, + stderr=subprocess.PIPE) + out, error = proc.communicate() + + kimchi_log.debug("Run command '%s'", " ".join(cmd)) + if out or error: + kimchi_log.debug("out:\n %s\nerror:\n %s", out, error) + except OSError as e: + kimchi_log.error("Failed to run command %s. %s", " ".join(cmd), + e.message) + return (None, None, None) + if proc.returncode != 0: + kimchi_log.debug("Cmd '%s' failed, error code: %s", cmd, error) + return (out, error, proc.returncode) + + +def name_uid(user): + return pwd.getpwnam(user).pw_uid + + +def get_group_ids(user): + gids = [g.gr_gid for g in grp.getgrall() if user in g.gr_mem] + gid = pwd.getpwnam(user).pw_gid + gids.append(grp.getgrgid(gid).gr_gid) + return gids + + +def get_groups(user): + gids = get_group_ids(user) + return [grp.getgrgid(gid).gr_name for gid in gids] + + +def run_setfacl_set_x(path, user="qemu", group=None):

+ set_user = ["setfacl", "--modify", "user:%s:x" % user, path] + set_group = ["setfacl", "--modify", "group:%s:x" % group, path] + out, error, ret = run_command(set_user) + if ret != 0 and group: + out, error, ret = run_command(set_group) + return ret == 0 + + +def run_getfacl(path, user="qemu", groups=None):

+ cmd = ["getfacl", path] + out, error, ret = run_command(cmd) + if out and ret == 0: + res = re.findall("user:%s:..x" % user, out) + if res: + return True + res = re.findall("(?<=group:)(.*)(?=:..x)", + out) if groups else [] + return list(set(res) & set(groups)) != [] + return False + + +def set_x_on_path(path, who="other"): + S_IXWHO = ((stat.S_IXUSR if who == "user" else None) or + (stat.S_IXGRP if who == "group" else None) or + stat.S_IXOTH) + mode = os.stat(path).st_mode | S_IXWHO + os.chmod(path, mode) + ret = os.stat(path).st_mode == mode + if not ret: + kimchi_log.debug("faild to set +x attribute on %s", path) + return ret + + +def get_x_on_path(path, uid, gids=[]): + try: + st = os.stat(path) + mode = st.st_mode + return ((uid == st.st_uid and mode & stat.S_IXUSR == stat.S_IXUSR) or + (st.st_gid in gids and mode & stat.S_IXGRP == stat.S_IXGRP) or + mode & stat.S_IXOTH == stat.S_IXOTH) + except OSError as e: + kimchi_log.error("faild to get attribute on %s as user id: %s. %s", + path, uid, e.message) + return False + +

+def reverse_paths(path): + paths = [] + while path: + paths.append(path) + if path == "/": + break + path = os.path.dirname(path) + + paths.reverse() + return paths +

+ +def check_path_permission(path, user='qemu', groups=[]): + groups = groups if groups else get_groups(user) + gids = [grp.getgrnam(group).gr_gid for group in groups] if groups else [] + paths = reverse_paths(path) + for path in paths: + if not (get_x_on_path(path, name_uid(user), gids) or + run_getfacl(path, user, groups)): + return False + return True + +

+def fix_path_permission(path, user='qemu', groups=[]): + groups = groups if groups else get_groups(user) + gids = [grp.getgrnam(group).gr_gid for group in groups] if groups else [] + paths = reverse_paths(path) + for path in paths: + if not (get_x_on_path(path, name_uid(user), gids) or + run_getfacl(path, user, groups) or + run_setfacl_set_x(path, user) or + set_x_on_path(path)): + return False + return True