2 * Copyright (C) 2019 Michael Jeanson <mjeanson@efficios.com>
4 * This library is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU Lesser General Public License as published by the
6 * Free Software Foundation; version 2.1 of the License.
8 * This library is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
13 * You should have received a copy of the GNU Lesser General Public License
14 * along with this library; if not, write to the Free Software Foundation,
15 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 #include <sys/types.h>
32 #include <common/compat/tid.h>
34 #include "signal-helper.h"
37 #define LTTNG_PROC_NS_PATH_MAX 40
40 static char *ns_opt
= NULL
;
41 static char *before_unshare_wait_file_path
= NULL
;
42 static char *after_unshare_wait_file_path
= NULL
;
43 static char *after_unshare_signal_file_path
= NULL
;
45 static struct poptOption opts
[] = {
46 /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
47 { "debug", 'd', POPT_ARG_NONE
, &debug
, 0, "Enable debug output", NULL
},
48 { "ns", 'n', POPT_ARG_STRING
, &ns_opt
, 0, "Namespace short identifier", NULL
},
49 { "before", 'b', POPT_ARG_STRING
, &before_unshare_wait_file_path
, 0, "Wait for file before unshare", NULL
},
50 { "after", 'a', POPT_ARG_STRING
, &after_unshare_wait_file_path
, 0, "Wait for file after unshare", NULL
},
51 { "signal", 's', POPT_ARG_STRING
, &after_unshare_signal_file_path
, 0, "Create signal file after unshare", NULL
},
53 { NULL
, 0, 0, NULL
, 0 }
56 static void debug_printf(const char *format
, ...)
59 va_start(args
, format
);
62 vfprintf(stderr
, format
, args
);
68 static int get_ns_inum(const char *ns
, ino_t
*ns_inum
)
72 char proc_ns_path
[LTTNG_PROC_NS_PATH_MAX
];
75 * /proc/thread-self was introduced in kernel v3.17
77 if (snprintf(proc_ns_path
, LTTNG_PROC_NS_PATH_MAX
,
78 "/proc/thread-self/ns/%s", ns
) >= 0) {
79 if (stat(proc_ns_path
, &sb
) == 0) {
87 if (snprintf(proc_ns_path
, LTTNG_PROC_NS_PATH_MAX
,
88 "/proc/self/task/%d/%s/net", lttng_gettid(), ns
) >= 0) {
89 if (stat(proc_ns_path
, &sb
) == 0) {
100 static int do_the_needful(int ns_flag
, const char *ns_str
)
105 ret
= get_ns_inum(ns_str
, &ns1
);
107 debug_printf("Failed to get ns inode number for namespace %s",
112 debug_printf("Initial %s ns inode number: %lu\n", ns_str
, ns1
);
114 /* Wait on synchronization before unshare. */
115 if (before_unshare_wait_file_path
) {
116 ret
= wait_on_file(before_unshare_wait_file_path
);
122 ret
= unshare(ns_flag
);
124 perror("Failed to unshare namespace");
128 ret
= get_ns_inum(ns_str
, &ns2
);
130 debug_printf("Failed to get ns inode number for namespace %s",
135 debug_printf("Post unshare %s ns inode number: %lu\n", ns_str
, ns2
);
137 /* Signal that the unshare call is completed. */
138 if (after_unshare_signal_file_path
) {
139 ret
= create_file(after_unshare_signal_file_path
);
145 /* Wait on synchronization after unshare. */
146 if (after_unshare_wait_file_path
) {
147 ret
= wait_on_file(after_unshare_wait_file_path
);
157 int main(int argc
, const char **argv
)
160 int ret
= EXIT_SUCCESS
;
163 pc
= poptGetContext(NULL
, argc
, argv
, opts
, 0);
164 poptReadDefaultConfig(pc
, 0);
167 poptPrintHelp(pc
, stderr
, 0);
172 while ((opt
= poptGetNextOpt(pc
)) >= 0) {
175 poptPrintUsage(pc
, stderr
, 0);
182 /* an error occurred during option processing */
183 poptPrintUsage(pc
, stderr
, 0);
184 fprintf(stderr
, "%s: %s\n",
185 poptBadOption(pc
, POPT_BADOPTION_NOALIAS
),
191 if (ns_opt
== NULL
) {
192 poptPrintUsage(pc
, stderr
, 0);
197 if (set_signal_handler()) {
202 if (strncmp(ns_opt
, "cgroup", 3) == 0) {
203 ret
= do_the_needful(CLONE_NEWCGROUP
, "cgroup");
204 } else if (strncmp(ns_opt
, "ipc", 3) == 0) {
205 ret
= do_the_needful(CLONE_NEWIPC
, "ipc");
206 } else if (strncmp(ns_opt
, "mnt", 3) == 0) {
207 ret
= do_the_needful(CLONE_NEWNS
, "mnt");
208 } else if (strncmp(ns_opt
, "net", 3) == 0) {
209 ret
= do_the_needful(CLONE_NEWNET
, "net");
210 } else if (strncmp(ns_opt
, "pid", 3) == 0) {
211 ret
= do_the_needful(CLONE_NEWPID
, "pid");
212 } else if (strncmp(ns_opt
, "user", 3) == 0) {
214 * Will always fail, requires a single threaded application,
215 * which can't happen with UST.
217 ret
= do_the_needful(CLONE_NEWUSER
, "user");
218 } else if (strncmp(ns_opt
, "uts", 3) == 0) {
219 ret
= do_the_needful(CLONE_NEWUTS
, "uts");
221 printf("invalid ns id\n");
225 ret
= ret
? EXIT_FAILURE
: EXIT_SUCCESS
;