Change seunshare to send kill signals to the childs session.

Also add signal handler to catch sigint, so if user enters ctrl-C sandbox will shutdown.
This commit is contained in:
Dan Walsh 2011-07-07 14:37:24 -04:00
parent 8dbd4d49f6
commit af0f4926da
2 changed files with 158 additions and 55 deletions

View File

@ -1664,7 +1664,7 @@ index ff0ee7c..0c8a085 100644
test:
@python test_sandbox.py -v
diff --git a/policycoreutils/sandbox/sandbox b/policycoreutils/sandbox/sandbox
index 48a26c2..41a3204 100644
index 48a26c2..4d17385 100644
--- a/policycoreutils/sandbox/sandbox
+++ b/policycoreutils/sandbox/sandbox
@@ -1,5 +1,6 @@
@ -1869,7 +1869,7 @@ index 48a26c2..41a3204 100644
if len(cmds) == 0:
self.usage(_("Command required"))
cmds[0] = fullpath(cmds[0])
@@ -329,44 +374,45 @@ sandbox [-h] [-[X|M] [-l level ] [-H homedir] [-T tempdir]] [-I includefile ] [-
@@ -329,44 +374,47 @@ sandbox [-h] [-[X|M] [-l level ] [-H homedir] [-T tempdir]] [-I includefile ] [-
def __setup_dir(self):
if self.__options.level or self.__options.session:
return
@ -1910,10 +1910,12 @@ index 48a26c2..41a3204 100644
- return rc
-
+ cmds = [ SEUNSHARE, "-Z", self.__execcon ]
+ if self.__options.usecgroup == True:
+ if self.__options.usecgroup:
+ cmds.append('-c')
+ if self.__options.usecaps == True:
+ if self.__options.usecaps:
+ cmds.append('-C')
+ if not self.__options.level:
+ cmds.append('-k')
if self.__mount:
- cmds = [ '/usr/sbin/seunshare', "-t", self.__tmpdir, "-h", self.__homedir, "--", self.__execcon ] + self.__paths
- rc = subprocess.Popen(cmds).wait()
@ -1935,7 +1937,7 @@ index 48a26c2..41a3204 100644
selinux.setexeccon(self.__execcon)
rc = subprocess.Popen(self.__cmds).wait()
@@ -404,7 +450,7 @@ if __name__ == '__main__':
@@ -404,7 +452,7 @@ if __name__ == '__main__':
sandbox = Sandbox()
rc = sandbox.main()
except OSError, error:
@ -2104,11 +2106,12 @@ index ff8b3ef..66aadfd 100644
}
diff --git a/policycoreutils/sandbox/sandboxX.sh b/policycoreutils/sandbox/sandboxX.sh
index 8338203..9648100 100644
index 8338203..0b0239c 100644
--- a/policycoreutils/sandbox/sandboxX.sh
+++ b/policycoreutils/sandbox/sandboxX.sh
@@ -1,13 +1,18 @@
@@ -1,15 +1,21 @@
#!/bin/bash
+trap "" TERM
context=`id -Z | secon -t -l -P`
export TITLE="Sandbox $context -- `grep ^#TITLE: ~/.sandboxrc | /usr/bin/cut -b8-80`"
-export SCREENSIZE="1000x700"
@ -2128,20 +2131,23 @@ index 8338203..9648100 100644
+ chmod +x ~/seremote
+ /usr/share/sandbox/start $HOME/.sandboxrc
export EXITCODE=$?
kill -HUP 0
- kill -HUP 0
+ kill -TERM 0
break
done
exit 0
diff --git a/policycoreutils/sandbox/seunshare.8 b/policycoreutils/sandbox/seunshare.8
new file mode 100644
index 0000000..eeb2218
index 0000000..c69ceda
--- /dev/null
+++ b/policycoreutils/sandbox/seunshare.8
@@ -0,0 +1,40 @@
@@ -0,0 +1,43 @@
+.TH SEUNSHARE "8" "May 2010" "seunshare" "User Commands"
+.SH NAME
+seunshare \- Run cmd with alternate homedir, tmpdir and/or SELinux context
+.SH SYNOPSIS
+.B seunshare
+[ -v ] [-c] [-C] [ -t tmpdir ] [ -h homedir ] [ -Z context ] -- executable [args]
+[-v] [-c] [-C] [-k] [ -t tmpdir ] [ -h homedir ] [ -Z context ] -- executable [args]
+.br
+.SH DESCRIPTION
+.PP
@ -2162,6 +2168,9 @@ index 0000000..eeb2218
+\fB\-C --capabilities\fR
+Allow apps executed within the namespace to use capabilities. Default is no capabilities.
+.TP
+\fB\-k --kill\fR
+Kill all processes with matching MCS level.
+.TP
+\fB\-Z\ context
+Use alternate SELinux context while runing the executable.
+.TP
@ -2177,10 +2186,10 @@ index 0000000..eeb2218
+and
+.I Thomas Liu <tliu@fedoraproject.org>
diff --git a/policycoreutils/sandbox/seunshare.c b/policycoreutils/sandbox/seunshare.c
index ec692e7..e3fa6bd 100644
index ec692e7..431271f 100644
--- a/policycoreutils/sandbox/seunshare.c
+++ b/policycoreutils/sandbox/seunshare.c
@@ -1,28 +1,35 @@
@@ -1,27 +1,35 @@
+/*
+ * Authors: Dan Walsh <dwalsh@redhat.com>
+ * Authors: Thomas Liu <tliu@fedoraproject.org>
@ -2213,15 +2222,15 @@ index ec692e7..e3fa6bd 100644
#include <selinux/selinux.h>
#include <selinux/context.h> /* for context-mangling functions */
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <unistd.h>
-
+#include <dirent.h>
#ifdef USE_NLS
#include <locale.h> /* for setlocale() */
#include <libintl.h> /* for gettext() */
@@ -39,29 +46,48 @@
@@ -39,29 +47,56 @@
#define MS_PRIVATE 1<<18
#endif
@ -2235,6 +2244,7 @@ index ec692e7..e3fa6bd 100644
+#define USAGE_STRING _("USAGE: seunshare [ -v ] [ -c ] -C -t tmpdir -h homedir [-Z context] -- executable [args]")
+
+static int verbose = 0;
+static int child = 0;
+
+static capng_select_t cap_set = CAPNG_SELECT_BOTH;
+
@ -2249,16 +2259,27 @@ index ec692e7..e3fa6bd 100644
- capng_clear(CAPNG_SELECT_BOTH);
-
- if (capng_lock() < 0)
- return -1;
- /* Change uid */
- if (setresuid(uid, uid, uid)) {
- fprintf(stderr, _("Error changing uid, aborting.\n"));
+ if (capng_have_capabilities(cap_set) == CAPNG_NONE)
+ return 0;
+ capng_clear(cap_set);
+ if (capng_lock() == -1 || capng_apply(cap_set) == -1) {
+ fprintf(stderr, _("Failed to drop all capabilities\n"));
return -1;
- /* Change uid */
- if (setresuid(uid, uid, uid)) {
- fprintf(stderr, _("Error changing uid, aborting.\n"));
+ }
+ return 0;
+}
+
+/**
+ * This function will drop all privileges.
+ */
+static int drop_privs(uid_t uid)
+{
+ if (drop_caps() == -1 || setresuid(uid, uid, uid) == -1) {
+ fprintf(stderr, _("Failed to drop privileges\n"));
return -1;
}
- return capng_apply(CAPNG_SELECT_BOTH);
+ return 0;
@ -2267,15 +2288,10 @@ index ec692e7..e3fa6bd 100644
-#define DEFAULT_PATH "/usr/bin:/bin"
-static int verbose = 0;
+/**
+ * This function will drop all privileges.
+ * If the user sends a siginto to seunshare, kill the child's session
+ */
+static int drop_privs(uid_t uid)
+{
+ if (drop_caps() == -1 || setresuid(uid, uid, uid) == -1) {
+ fprintf(stderr, _("Failed to drop privileges\n"));
+ return -1;
+ }
+ return 0;
+void handler(int sig) {
+ if (child > 0) kill(-child,sig);
+}
/**
@ -2284,21 +2300,25 @@ index ec692e7..e3fa6bd 100644
*/
static int set_signal_handles(void)
{
@@ -75,8 +101,8 @@ static int set_signal_handles(void)
@@ -75,32 +110,117 @@ static int set_signal_handles(void)
(void)sigprocmask(SIG_SETMASK, &empty, NULL);
- /* Terminate on SIGHUP. */
- if (signal(SIGHUP, SIG_DFL) == SIG_ERR) {
+ /* Terminate on SIGHUP */
+ if (signal(SIGHUP, SIG_IGN) == SIG_ERR) {
if (signal(SIGHUP, SIG_DFL) == SIG_ERR) {
perror("Unable to set SIGHUP handler");
return -1;
}
@@ -84,23 +110,103 @@ static int set_signal_handles(void)
return 0;
}
+ if (signal(SIGINT, handler) == SIG_ERR) {
+ perror("Unable to set SIGHUP handler");
+ return -1;
+ }
+
+ return 0;
+}
+
+#define status_to_retval(status,retval) do { \
+ if ((status) == -1) \
+ retval = -1; \
@ -2365,9 +2385,9 @@ index ec692e7..e3fa6bd 100644
+ fprintf(stderr, _("Error: %s not owned by GID %d\n"), file, gid);
+ return -1;
+ }
+ return 0;
+}
+
return 0;
}
+#define equal_stats(one,two) \
+ ((one)->st_dev == (two)->st_dev && (one)->st_ino == (two)->st_ino && \
+ (one)->st_uid == (two)->st_uid && (one)->st_gid == (two)->st_gid && \
@ -2409,7 +2429,7 @@ index ec692e7..e3fa6bd 100644
return 0;
}
@@ -123,7 +229,7 @@ static int verify_shell(const char *shell_name)
@@ -123,7 +243,7 @@ static int verify_shell(const char *shell_name)
/* check the shell skipping newline char */
if (!strcmp(shell_name, buf)) {
@ -2418,7 +2438,7 @@ index ec692e7..e3fa6bd 100644
break;
}
}
@@ -131,45 +237,530 @@ static int verify_shell(const char *shell_name)
@@ -131,45 +251,594 @@ static int verify_shell(const char *shell_name)
return rc;
}
@ -2817,9 +2837,8 @@ index ec692e7..e3fa6bd 100644
+ setfsuid(pwd->pw_uid);
+
+ return 0;
}
-#define USAGE_STRING _("USAGE: seunshare [ -v ] [ -t tmpdir ] [ -h homedir ] -- CONTEXT executable [args] ")
+}
+
+/**
+ * seunshare will create a tmpdir in /tmp, with root ownership. The parent
+ * process waits for it child to exit to attempt to remove the directory. If
@ -2931,6 +2950,69 @@ index ec692e7..e3fa6bd 100644
+ if (fd_t >= 0) close(fd_t);
+ if (fd_s >= 0) close(fd_s);
+ return tmpdir;
}
-#define USAGE_STRING _("USAGE: seunshare [ -v ] [ -t tmpdir ] [ -h homedir ] -- CONTEXT executable [args] ")
+#define PROC_BASE "/proc"
+
+static int
+killall (security_context_t execcon)
+{
+ DIR *dir;
+ security_context_t scon;
+ struct dirent *de;
+ pid_t *pid_table, pid, self;
+ int i;
+ int pids, max_pids;
+ int running = 0;
+ self = getpid();
+ if (!(dir = opendir(PROC_BASE))) {
+ return -1;
+ }
+ max_pids = 256;
+ pid_table = malloc(max_pids * sizeof (pid_t));
+ if (!pid_table) {
+ return -1;
+ }
+ pids = 0;
+ context_t con;
+ con = context_new(execcon);
+ const char *mcs = context_range_get(con);
+ printf("mcs=%s\n", mcs);
+ while ((de = readdir (dir)) != NULL) {
+ if (!(pid = (pid_t)atoi(de->d_name)) || pid == self)
+ continue;
+
+ if (pids == max_pids) {
+ if (!(pid_table = realloc(pid_table, 2*pids*sizeof(pid_t)))) {
+ return -1;
+ }
+ max_pids *= 2;
+ }
+ pid_table[pids++] = pid;
+ }
+
+ (void)closedir(dir);
+
+ for (i = 0; i < pids; i++) {
+ pid_t id = pid_table[i];
+
+ if (getpidcon(id, &scon) == 0) {
+
+ context_t pidcon = context_new(scon);
+ /* Attempt to kill remaining processes */
+ if (strcmp(context_range_get(pidcon), mcs) == 0)
+ kill(id, SIGKILL);
+
+ context_free(pidcon);
+ freecon(scon);
+ }
+ running++;
+ }
+
+ context_free(con);
+ free(pid_table);
+ return running;
+}
int main(int argc, char **argv) {
@ -2944,6 +3026,7 @@ index ec692e7..e3fa6bd 100644
int clflag; /* holds codes for command line flags */
- char *tmpdir_s = NULL; /* tmpdir spec'd by user in argv[] */
+ int usecgroups = 0;
+ int kill_all = 0;
+
char *homedir_s = NULL; /* homedir spec'd by user in argv[] */
+ char *tmpdir_s = NULL; /* tmpdir spec'd by user in argv[] */
@ -2956,6 +3039,7 @@ index ec692e7..e3fa6bd 100644
const struct option long_options[] = {
{"homedir", 1, 0, 'h'},
{"tmpdir", 1, 0, 't'},
+ {"kill", 1, 0, 'k'},
{"verbose", 1, 0, 'v'},
+ {"cgroups", 1, 0, 'c'},
+ {"context", 1, 0, 'Z'},
@ -2963,7 +3047,7 @@ index ec692e7..e3fa6bd 100644
{NULL, 0, 0, 0}
};
@@ -180,6 +771,12 @@ int main(int argc, char **argv) {
@@ -180,6 +849,12 @@ int main(int argc, char **argv) {
return -1;
}
@ -2976,7 +3060,7 @@ index ec692e7..e3fa6bd 100644
struct passwd *pwd=getpwuid(uid);
if (!pwd) {
perror(_("getpwduid failed"));
@@ -187,34 +784,33 @@ int main(int argc, char **argv) {
@@ -187,34 +862,36 @@ int main(int argc, char **argv) {
}
if (verify_shell(pwd->pw_shell) < 0) {
@ -3000,6 +3084,9 @@ index ec692e7..e3fa6bd 100644
- }
- if (verify_mount(tmpdir_s, pwd) < 0) return -1;
+ tmpdir_s = optarg;
+ break;
+ case 'k':
+ kill_all = 1;
break;
case 'h':
- if (!(homedir_s = realpath(optarg, NULL))) {
@ -3025,7 +3112,7 @@ index ec692e7..e3fa6bd 100644
break;
default:
fprintf(stderr, "%s\n", USAGE_STRING);
@@ -223,76 +819,84 @@ int main(int argc, char **argv) {
@@ -223,76 +900,84 @@ int main(int argc, char **argv) {
}
if (! homedir_s && ! tmpdir_s) {
@ -3067,9 +3154,6 @@ index ec692e7..e3fa6bd 100644
- if (tmpdir_s && seunshare_mount(tmpdir_s, "/tmp", pwd) < 0)
- return -1;
- }
-
- if (drop_capabilities(uid)) {
- perror(_("Failed to drop all capabilities"));
+ if (set_signal_handles()) return -1;
+
+ if (usecgroups && setup_cgroups() < 0) return -1;
@ -3088,7 +3172,9 @@ index ec692e7..e3fa6bd 100644
+ verify_directory(tmpdir_s, NULL, &st_tmpdir_s) < 0 ||
+ check_owner_uid(uid, tmpdir_s, &st_tmpdir_s))) return -1;
+ setfsuid(0);
+
- if (drop_capabilities(uid)) {
- perror(_("Failed to drop all capabilities"));
+ /* create runtime tmpdir */
+ if (tmpdir_s && (tmpdir_r = create_tmpdir(tmpdir_s, &st_tmpdir_s,
+ &st_tmpdir_r, pwd, execcon)) == NULL) {
@ -3096,8 +3182,9 @@ index ec692e7..e3fa6bd 100644
return -1;
}
- int child = fork();
+ /* spawn child process */
int child = fork();
+ child = fork();
if (child == -1) {
perror(_("Unable to fork"));
- return -1;
@ -3159,7 +3246,7 @@ index ec692e7..e3fa6bd 100644
if (display)
rc |= setenv("DISPLAY", display, 1);
rc |= setenv("HOME", pwd->pw_dir, 1);
@@ -300,22 +904,41 @@ int main(int argc, char **argv) {
@@ -300,22 +985,47 @@ int main(int argc, char **argv) {
rc |= setenv("USER", pwd->pw_name, 1);
rc |= setenv("LOGNAME", pwd->pw_name, 1);
rc |= setenv("PATH", DEFAULT_PATH, 1);
@ -3195,10 +3282,16 @@ index ec692e7..e3fa6bd 100644
- free(tmpdir_s);
- free(homedir_s);
+ drop_caps();
+
+ /* parent waits for child exit to do the cleanup */
+ waitpid(child, &status, 0);
+ status_to_retval(status, status);
+ /* Make sure all child processes exit */
+ kill(-child,SIGTERM);
+
+ if (execcon && kill)
+ killall(execcon);
+
+ if (tmpdir_r) cleanup_tmpdir(tmpdir_r, tmpdir_s, pwd, 1);
+

View File

@ -7,7 +7,7 @@
Summary: SELinux policy core utilities
Name: policycoreutils
Version: 2.0.86
Release: 15%{?dist}
Release: 18%{?dist}
License: GPLv2
Group: System Environment/Base
# Based on git repository with tag 20101221
@ -349,7 +349,17 @@ fi
/bin/systemctl try-restart restorecond.service >/dev/null 2>&1 || :
%changelog
* Mon Jul 5 2011 Dan Walsh <dwalsh@redhat.com> 2.0.86-16
* Thu Jul 7 2011 Dan Walsh <dwalsh@redhat.com> 2.0.86-18
- Change seunshare to send kill signals to the childs session.
- Also add signal handler to catch sigint, so if user enters ctrl-C sandbox will shutdown.
* Wed Jul 6 2011 Dan Walsh <dwalsh@redhat.com> 2.0.86-17
- Add -k qualifier to seunshare to have it attempt to kill all processes with
the matching MCS label.
sandbox will default to using the -k, if the level was not specified.
This is added to make sure all processes are killed with the sandbox exits.
* Tue Jul 5 2011 Dan Walsh <dwalsh@redhat.com> 2.0.86-16
- Add -C option to sandbox and seunshare to maintain capabilities, otherwise
the bounding set will be dropped.
- Change --cgroups short name -c rather then -C for consistancy