1 /*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <stdio.h>
18 #include <stdlib.h>
19 #include <sys/types.h>
20 #include <sys/wait.h>
21 #include <errno.h>
22 #include <string.h>
23 #include <unistd.h>
24
25 #include <string>
26
27 #define LOG_TAG "OemIptablesHook"
28 #include <log/log.h>
29 #include <logwrap/logwrap.h>
30 #include "NetdConstants.h"
31
32 namespace {
33
34 const char OEM_SCRIPT_PATH[] = "/system/bin/oem-iptables-init.sh";
35
oemCleanupHooks()36 bool oemCleanupHooks() {
37 static const std::string cmd4 =
38 "*filter\n"
39 ":oem_out -\n"
40 ":oem_fwd -\n"
41 "COMMIT\n"
42 "*nat\n"
43 ":oem_nat_pre -\n"
44 "COMMIT\n";
45
46 static const std::string cmd6 =
47 "*filter\n"
48 ":oem_out -\n"
49 ":oem_fwd -\n"
50 "COMMIT\n";
51
52 return (execIptablesRestore(V4, cmd4) == 0 && execIptablesRestore(V6, cmd6) == 0);
53 }
54
oemInitChains()55 bool oemInitChains() {
56 int ret = system(OEM_SCRIPT_PATH); // NOLINT(cert-env33-c)
57 if ((-1 == ret) || (0 != WEXITSTATUS(ret))) {
58 ALOGE("%s failed: %s", OEM_SCRIPT_PATH, strerror(errno));
59 oemCleanupHooks();
60 return false;
61 }
62 return true;
63 }
64
65 } // namespace
66
setupOemIptablesHook()67 void setupOemIptablesHook() {
68 if (0 == access(OEM_SCRIPT_PATH, R_OK | X_OK)) {
69 // The call to oemCleanupHooks() is superfluous when done on bootup,
70 // but is needed for the case where netd has crashed/stopped and is
71 // restarted.
72 if (oemCleanupHooks() && oemInitChains()) {
73 ALOGI("OEM iptable hook installed.");
74 }
75 }
76 }
77