1 /*
2 * Copyright (C) 2017 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 <vector>
18
19 #include <string.h>
20
21 #include "log.h"
22 #include "namespace.h"
23 #include "proxy.h"
24
usage(const char * program)25 void usage(const char* program) {
26 loge("Usage: %s -n [namespace|pid] -o <outer if> -i <inner ifs>\n",
27 program);
28 loge(" -o Outer interface that connects to an existing IPv6 network.\n"
29 " -i Comma separated list of inner interfaces that would like\n"
30 " to access the IPv6 network available on the outer interface.\n"
31 " -n Optional parameter that causes the proxy to run in the given\n"
32 " network namespace. If a name is given instead of a PID the\n"
33 " namespace is expected to be set up by iproute2 or with a\n"
34 " similar approach where the namespace is linked in\n"
35 " /var/run/netns. A PID is assumed if the argument is numeric.\n"
36 " If providing a PID the same namespace that the PID is\n"
37 " running in will be used. In this scenario there is no\n"
38 " requirement for a file in /var/run/netns.\n"
39 "\n"
40 " The proxy will ensure that router solicitations from inner\n"
41 " interfaces are forwarded to the outer interface and that\n"
42 " router advertisements from the outer interface are forwarded\n"
43 " to the inner interfaces. In addition to this neighbor\n"
44 " solicitations and advertisements will also be forwarded in a\n"
45 " way that enables IPv6 connectivity and routes will be set up\n"
46 " for source addresses on the inner interfaces so that replies\n"
47 " can reach those sources as expected.\n"
48 );
49 }
50
splitString(char * str,char delimiter)51 static std::vector<const char*> splitString(char* str, char delimiter) {
52 std::vector<const char*> parts;
53 char* part = nullptr;
54 do {
55 parts.push_back(str);
56 part = strchr(str, delimiter);
57 if (part != nullptr) {
58 *part = '\0';
59 str = part + 1;
60 }
61 } while (part != nullptr);
62 return parts;
63 }
64
main(int argc,char * argv[])65 int main(int argc, char* argv[]) {
66 char* inner = nullptr;
67 const char* outer = nullptr;
68 const char* netNamespace = nullptr;
69 for (int i = 1; i < argc; ++i) {
70 if (strcmp(argv[i], "-o") == 0) {
71 outer = argv[++i];
72 } else if (strcmp(argv[i], "-i") == 0) {
73 inner = argv[++i];
74 } else if (strcmp(argv[i], "-h") == 0 ||
75 strcmp(argv[i], "--help") == 0) {
76 usage(argv[0]);
77 return 1;
78 } else if (strcmp(argv[i], "-n") == 0) {
79 netNamespace = argv[++i];
80 } else {
81 loge("ERROR: Unknown argument '%s'\n\n", argv[i]);
82 usage(argv[0]);
83 return 1;
84 }
85 }
86 bool error = false;
87 if (inner == nullptr) {
88 loge("ERROR: Missing inner interface\n");
89 error = true;
90 }
91 if (outer == nullptr) {
92 loge("ERROR: Missing outer interface\n");
93 error = true;
94 }
95 if (netNamespace) {
96 if (!setNetworkNamespace(netNamespace)) {
97 error = true;
98 }
99 }
100 if (error) {
101 usage(argv[0]);
102 return 1;
103 }
104
105 std::vector<const char*> innerInterfaces = splitString(inner, ',');
106
107 Proxy proxy(outer, innerInterfaces.begin(), innerInterfaces.end());
108
109 return proxy.run();
110 }
111
112