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 "NetdConstants.h"
30
31 namespace {
32
33 const char OEM_SCRIPT_PATH[] = "/system/bin/oem-iptables-init.sh";
34
oemCleanupHooks()35 bool oemCleanupHooks() {
36 static const std::string cmd4 =
37 "*filter\n"
38 ":oem_out -\n"
39 ":oem_fwd -\n"
40 "COMMIT\n"
41 "*nat\n"
42 ":oem_nat_pre -\n"
43 "COMMIT\n";
44
45 static const std::string cmd6 =
46 "*filter\n"
47 ":oem_out -\n"
48 ":oem_fwd -\n"
49 "COMMIT\n";
50
51 return (execIptablesRestore(V4, cmd4) == 0 && execIptablesRestore(V6, cmd6) == 0);
52 }
53
oemInitChains()54 bool oemInitChains() {
55 int ret = system(OEM_SCRIPT_PATH); // NOLINT(cert-env33-c)
56 if ((-1 == ret) || (0 != WEXITSTATUS(ret))) {
57 ALOGE("%s failed: %s", OEM_SCRIPT_PATH, strerror(errno));
58 oemCleanupHooks();
59 return false;
60 }
61 return true;
62 }
63
64 } // namespace
65
setupOemIptablesHook()66 void setupOemIptablesHook() {
67 if (0 == access(OEM_SCRIPT_PATH, R_OK | X_OK)) {
68 // The call to oemCleanupHooks() is superfluous when done on bootup,
69 // but is needed for the case where netd has crashed/stopped and is
70 // restarted.
71 if (oemCleanupHooks() && oemInitChains()) {
72 ALOGI("OEM iptable hook installed.");
73 }
74 }
75 }
76