diff options
Diffstat (limited to 'src/firejail/netns.c')
-rw-r--r-- | src/firejail/netns.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/src/firejail/netns.c b/src/firejail/netns.c new file mode 100644 index 000000000..477d56b3d --- /dev/null +++ b/src/firejail/netns.c | |||
@@ -0,0 +1,114 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2017 Firejail Authors | ||
3 | * | ||
4 | * This file is part of firejail project | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or modify | ||
7 | * it under the terms of the GNU General Public License as published by | ||
8 | * the Free Software Foundation; either version 2 of the License, or | ||
9 | * (at your option) any later version. | ||
10 | * | ||
11 | * This program is distributed in the hope that it will be useful, | ||
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
14 | * GNU General Public License for more details. | ||
15 | * | ||
16 | * You should have received a copy of the GNU General Public License along | ||
17 | * with this program; if not, write to the Free Software Foundation, Inc., | ||
18 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. | ||
19 | */ | ||
20 | #include "firejail.h" | ||
21 | #include <stdio.h> | ||
22 | #include <string.h> | ||
23 | #include <errno.h> | ||
24 | #include <sys/types.h> | ||
25 | #include <sys/mount.h> | ||
26 | #include <sys/stat.h> | ||
27 | #include <sys/syscall.h> | ||
28 | #include <dirent.h> | ||
29 | #include <fcntl.h> | ||
30 | #include <sched.h> | ||
31 | #include <unistd.h> | ||
32 | |||
33 | static char *netns_control_file(const char *nsname) { | ||
34 | char *rv = 0; | ||
35 | if (asprintf(&rv, "/var/run/netns/%s", nsname) <= 0) | ||
36 | errExit("asprintf"); | ||
37 | return rv; | ||
38 | } | ||
39 | |||
40 | static char *netns_etc_dir(const char *nsname) { | ||
41 | char *rv = 0; | ||
42 | if (asprintf(&rv, "/etc/netns/%s", nsname) <= 0) | ||
43 | errExit("asprintf"); | ||
44 | return rv; | ||
45 | } | ||
46 | |||
47 | void check_netns(const char *nsname) { | ||
48 | if (strchr(nsname, '/') || strstr(nsname, "..")) { | ||
49 | fprintf(stderr, "Error: invalid netns name %s\n", nsname); | ||
50 | exit(1); | ||
51 | } | ||
52 | invalid_filename(nsname); | ||
53 | char *control_file = netns_control_file(nsname); | ||
54 | |||
55 | EUID_ASSERT(); | ||
56 | |||
57 | struct stat st; | ||
58 | if (lstat(control_file, &st)) { | ||
59 | fprintf(stderr, "Error: invalid netns '%s' (%s: %s)\n", | ||
60 | nsname, control_file, strerror(errno)); | ||
61 | exit(1); | ||
62 | } | ||
63 | if (!S_ISREG(st.st_mode)) { | ||
64 | fprintf(stderr, "Error: invalid netns '%s' (%s: not a regular file)\n", | ||
65 | nsname, control_file); | ||
66 | exit(1); | ||
67 | } | ||
68 | free(control_file); | ||
69 | } | ||
70 | |||
71 | void netns(const char *nsname) { | ||
72 | char *control_file = netns_control_file(nsname); | ||
73 | int nsfd = open(control_file, O_RDONLY|O_CLOEXEC); | ||
74 | if (nsfd < 0) { | ||
75 | fprintf(stderr, "Error: cannot open netns '%s' (%s: %s)\n", | ||
76 | nsname, control_file, strerror(errno)); | ||
77 | exit(1); | ||
78 | } | ||
79 | if (syscall(__NR_setns, nsfd, CLONE_NEWNET) < 0) { | ||
80 | fprintf(stderr, "Error: cannot join netns '%s': %s\n", | ||
81 | nsname, strerror(errno)); | ||
82 | exit(1); | ||
83 | } | ||
84 | close(nsfd); | ||
85 | free(control_file); | ||
86 | } | ||
87 | |||
88 | void netns_mounts(const char *nsname) { | ||
89 | char *etcdir = netns_etc_dir(nsname); | ||
90 | char *netns_name, *etc_name; | ||
91 | struct dirent *entry; | ||
92 | DIR *dir; | ||
93 | |||
94 | dir = opendir(etcdir); | ||
95 | if (!dir) { | ||
96 | free(etcdir); | ||
97 | return; | ||
98 | } | ||
99 | while ((entry = readdir(dir))) { | ||
100 | if (!strcmp(entry->d_name, ".") || !strcmp(entry->d_name, "..")) | ||
101 | continue; | ||
102 | if (asprintf(&netns_name, "%s/%s", etcdir, entry->d_name) < 0 || | ||
103 | asprintf(&etc_name, "/etc/%s", entry->d_name) < 0) | ||
104 | errExit("asprintf"); | ||
105 | if (mount(netns_name, etc_name, "none", MS_BIND, 0) < 0) { | ||
106 | fprintf(stderr, "Warning: bind %s -> %s failed: %s\n", | ||
107 | netns_name, etc_name, strerror(errno)); | ||
108 | } | ||
109 | free(netns_name); | ||
110 | free(etc_name); | ||
111 | } | ||
112 | closedir(dir); | ||
113 | free(etcdir); | ||
114 | } | ||