/*
* Copyright (c) Huawei Technologies Co., Ltd., 2015
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version. This program 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 General
* Public License for more details. You should have received a copy of the GNU
* General Public License along with this program.
*/
/*
* Verify that:
* /proc/PID/uid_map and /proc/PID/gid_map contains three values separated by
* white space:
* ID-inside-ns ID-outside-ns length
*
* ID-outside-ns is interpreted according to which process is opening the file.
* If the process opening the file is in the same user namespace as the process
* PID, then ID-outside-ns is defined with respect to the parent user namespace.
* If the process opening the file is in a different user namespace, then
* ID-outside-ns is defined with respect to the user namespace of the process
* opening the file.
*
* The string "deny" would be written to /proc/self/setgroups before GID
* check if setgroups is allowed, see kernel commits:
*
* commit 9cc46516ddf497ea16e8d7cb986ae03a0f6b92f8
* Author: Eric W. Biederman <ebiederm@xmission.com>
* Date: Tue Dec 2 12:27:26 2014 -0600
* userns: Add a knob to disable setgroups on a per user namespace basis
*
* commit 66d2f338ee4c449396b6f99f5e75cd18eb6df272
* Author: Eric W. Biederman <ebiederm@xmission.com>
* Date: Fri Dec 5 19:36:04 2014 -0600
* userns: Allow setting gid_maps without privilege when setgroups is disabled
*
*/
#define _GNU_SOURCE
#include <sys/wait.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include "userns_helper.h"
#include "test.h"
#define CHILD1UID 0
#define CHILD1GID 0
#define CHILD2UID 200
#define CHILD2GID 200
#define UID_MAP 0
#define GID_MAP 1
char *TCID = "user_namespace3";
int TST_TOTAL = 1;
static int cpid1, parentuid, parentgid;
/*
* child_fn1() - Inside a new user namespace
*/
static int child_fn1(void)
{
TST_SAFE_CHECKPOINT_WAIT(NULL, 0);
return 0;
}
/*
* child_fn2() - Inside a new user namespace
*/
static int child_fn2(void)
{
int exit_val = 0;
int uid, gid;
char cpid1uidpath[BUFSIZ];
char cpid1gidpath[BUFSIZ];
int idinsidens, idoutsidens, length;
TST_SAFE_CHECKPOINT_WAIT(NULL, 1);
uid = geteuid();
gid = getegid();
if (uid != CHILD2UID || gid != CHILD2GID) {
printf("unexpected uid=%d gid=%d\n", uid, gid);
exit_val = 1;
}
/*Get the uid parameters of the child_fn2 process.*/
SAFE_FILE_SCANF(NULL, "/proc/self/uid_map", "%d %d %d", &idinsidens,
&idoutsidens, &length);
/* map file format:ID-inside-ns ID-outside-ns length
If the process opening the file is in the same user namespace as
the process PID, then ID-outside-ns is defined with respect to the
parent user namespace.*/
if (idinsidens != CHILD2UID || idoutsidens != parentuid) {
printf("child_fn2 checks /proc/cpid2/uid_map:\n");
printf("unexpected: idinsidens=%d idoutsidens=%d\n",
idinsidens, idoutsidens);
exit_val = 1;
}
sprintf(cpid1uidpath, "/proc/%d/uid_map", cpid1);
SAFE_FILE_SCANF(NULL, cpid1uidpath, "%d %d %d", &idinsidens,
&idoutsidens, &length);
/* If the process opening the file is in a different user namespace,
then ID-outside-ns is defined with respect to the user namespace
of the process opening the file.*/
if (idinsidens != CHILD1UID || idoutsidens != CHILD2UID) {
printf("child_fn2 checks /proc/cpid1/uid_map:\n");
printf("unexpected: idinsidens=%d idoutsidens=%d\n",
idinsidens, idoutsidens);
exit_val = 1;
}
sprintf(cpid1gidpath, "/proc/%d/gid_map", cpid1);
SAFE_FILE_SCANF(NULL, "/proc/self/gid_map", "%d %d %d",
&idinsidens, &idoutsidens, &length);
if (idinsidens != CHILD2GID || idoutsidens != parentgid) {
printf("child_fn2 checks /proc/cpid2/gid_map:\n");
printf("unexpected: idinsidens=%d idoutsidens=%d\n",
idinsidens, idoutsidens);
exit_val = 1;
}
SAFE_FILE_SCANF(NULL, cpid1gidpath, "%d %d %d", &idinsidens,
&idoutsidens, &length);
if (idinsidens != CHILD1GID || idoutsidens != CHILD2GID) {
printf("child_fn1 checks /proc/cpid1/gid_map:\n");
printf("unexpected: idinsidens=%d idoutsidens=%d\n",
idinsidens, idoutsidens);
exit_val = 1;
}
TST_SAFE_CHECKPOINT_WAKE(NULL, 0);
TST_SAFE_CHECKPOINT_WAKE(NULL, 1);
return exit_val;
}
static void cleanup(void)
{
tst_rmdir();
}
static void setup(void)
{
check_newuser();
tst_tmpdir();
TST_CHECKPOINT_INIT(NULL);
}
int main(int argc, char *argv[])
{
pid_t cpid2;
char path[BUFSIZ];
int lc;
int fd;
int ret;
tst_parse_opts(argc, argv, NULL, NULL);
setup();
for (lc = 0; TEST_LOOPING(lc); lc++) {
tst_count = 0;
parentuid = geteuid();
parentgid = getegid();
cpid1 = ltp_clone_quick(CLONE_NEWUSER | SIGCHLD,
(void *)child_fn1, NULL);
if (cpid1 < 0)
tst_brkm(TBROK | TERRNO, cleanup,
"cpid1 clone failed");
cpid2 = ltp_clone_quick(CLONE_NEWUSER | SIGCHLD,
(void *)child_fn2, NULL);
if (cpid2 < 0)
tst_brkm(TBROK | TERRNO, cleanup,
"cpid2 clone failed");
if (access("/proc/self/setgroups", F_OK) == 0) {
sprintf(path, "/proc/%d/setgroups", cpid1);
fd = SAFE_OPEN(cleanup, path, O_WRONLY, 0644);
SAFE_WRITE(cleanup, 1, fd, "deny", 4);
SAFE_CLOSE(cleanup, fd);
/* If the setgroups file has the value "deny",
* then the setgroups(2) system call can't
* subsequently be reenabled (by writing "allow" to
* the file) in this user namespace. (Attempts to
* do so will fail with the error EPERM.)
*/
/* test that setgroups can't be re-enabled */
fd = SAFE_OPEN(cleanup, path, O_WRONLY, 0644);
ret = write(fd, "allow", 5);
if (ret != -1) {
tst_brkm(TBROK | TERRNO, cleanup,
"write action should fail");
} else if (errno != EPERM) {
tst_brkm(TBROK | TERRNO, cleanup,
"unexpected error: \n");
}
SAFE_CLOSE(cleanup, fd);
tst_resm(TPASS, "setgroups can't be re-enabled");
sprintf(path, "/proc/%d/setgroups", cpid2);
fd = SAFE_OPEN(cleanup, path, O_WRONLY, 0644);
SAFE_WRITE(cleanup, 1, fd, "deny", 4);
SAFE_CLOSE(cleanup, fd);
}
updatemap(cpid1, UID_MAP, CHILD1UID, parentuid, cleanup);
updatemap(cpid2, UID_MAP, CHILD2UID, parentuid, cleanup);
updatemap(cpid1, GID_MAP, CHILD1GID, parentgid, cleanup);
updatemap(cpid2, GID_MAP, CHILD2GID, parentgid, cleanup);
TST_SAFE_CHECKPOINT_WAKE_AND_WAIT(cleanup, 1);
tst_record_childstatus(cleanup, cpid1);
tst_record_childstatus(cleanup, cpid2);
}
cleanup();
tst_exit();
}