1 /*
2  * Copyright 2016 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  * IptablesBaseTest.cpp - utility class for tests that use iptables
17  */
18 
19 #include <string>
20 #include <vector>
21 
22 #include <gtest/gtest.h>
23 
24 #include "IptablesBaseTest.h"
25 #include "NetdConstants.h"
26 
IptablesBaseTest()27 IptablesBaseTest::IptablesBaseTest() {
28     sCmds.clear();
29     sRestoreCmds.clear();
30 }
31 
fake_android_fork_exec(int argc,char * argv[],int * status,bool,bool)32 int IptablesBaseTest::fake_android_fork_exec(int argc, char* argv[], int *status, bool, bool) {
33     std::string cmd = argv[0];
34     for (int i = 1; i < argc; i++) {
35         cmd += " ";
36         cmd += argv[i];
37     }
38     sCmds.push_back(cmd);
39     *status = 0;
40     return 0;
41 }
42 
fakeExecIptables(IptablesTarget target,...)43 int IptablesBaseTest::fakeExecIptables(IptablesTarget target, ...) {
44     std::string cmd = " -w";
45     va_list args;
46     va_start(args, target);
47     const char *arg;
48     do {
49         arg = va_arg(args, const char *);
50         if (arg != nullptr) {
51             cmd += " ";
52             cmd += arg;
53         }
54     } while (arg);
55 
56     if (target == V4 || target == V4V6) {
57         sCmds.push_back(IPTABLES_PATH + cmd);
58     }
59     if (target == V6 || target == V4V6) {
60         sCmds.push_back(IP6TABLES_PATH + cmd);
61     }
62 
63     return 0;
64 }
65 
fakeExecIptablesRestore(IptablesTarget target,const std::string & commands)66 int IptablesBaseTest::fakeExecIptablesRestore(IptablesTarget target, const std::string& commands) {
67     sRestoreCmds.push_back({ target, commands });
68     return 0;
69 }
70 
expectIptablesCommand(IptablesTarget target,int pos,const std::string & cmd)71 int IptablesBaseTest::expectIptablesCommand(IptablesTarget target, int pos,
72                                             const std::string& cmd) {
73 
74     if ((unsigned) pos >= sCmds.size()) {
75         ADD_FAILURE() << "Expected too many iptables commands, want command "
76                << pos + 1 << "/" << sCmds.size();
77         return -1;
78     }
79 
80     if (target == V4 || target == V4V6) {
81         EXPECT_EQ("/system/bin/iptables -w " + cmd, sCmds[pos++]);
82     }
83     if (target == V6 || target == V4V6) {
84         EXPECT_EQ("/system/bin/ip6tables -w " + cmd, sCmds[pos++]);
85     }
86 
87     return target == V4V6 ? 2 : 1;
88 }
89 
expectIptablesCommands(const std::vector<std::string> & expectedCmds)90 void IptablesBaseTest::expectIptablesCommands(const std::vector<std::string>& expectedCmds) {
91     ExpectedIptablesCommands expected;
92     for (auto cmd : expectedCmds) {
93         expected.push_back({ V4V6, cmd });
94     }
95     expectIptablesCommands(expected);
96 }
97 
expectIptablesCommands(const ExpectedIptablesCommands & expectedCmds)98 void IptablesBaseTest::expectIptablesCommands(const ExpectedIptablesCommands& expectedCmds) {
99     size_t pos = 0;
100     for (size_t i = 0; i < expectedCmds.size(); i ++) {
101         auto target = expectedCmds[i].first;
102         auto cmd = expectedCmds[i].second;
103         int numConsumed = expectIptablesCommand(target, pos, cmd);
104         if (numConsumed < 0) {
105             // Read past the end of the array.
106             break;
107         }
108         pos += numConsumed;
109     }
110 
111     EXPECT_EQ(pos, sCmds.size());
112     sCmds.clear();
113 }
114 
expectIptablesRestoreCommands(const std::vector<std::string> & expectedCmds)115 void IptablesBaseTest::expectIptablesRestoreCommands(const std::vector<std::string>& expectedCmds) {
116     ExpectedIptablesCommands expected;
117     for (auto cmd : expectedCmds) {
118         expected.push_back({ V4V6, cmd });
119     }
120     expectIptablesRestoreCommands(expected);
121 }
122 
expectIptablesRestoreCommands(const ExpectedIptablesCommands & expectedCmds)123 void IptablesBaseTest::expectIptablesRestoreCommands(const ExpectedIptablesCommands& expectedCmds) {
124     EXPECT_EQ(expectedCmds.size(), sRestoreCmds.size());
125     for (size_t i = 0; i < expectedCmds.size(); i++) {
126         EXPECT_EQ(expectedCmds[i], sRestoreCmds[i]) <<
127             "iptables-restore command " << i << " differs";
128     }
129     sRestoreCmds.clear();
130 }
131 
132 std::vector<std::string> IptablesBaseTest::sCmds = {};
133 IptablesBaseTest::ExpectedIptablesCommands IptablesBaseTest::sRestoreCmds = {};
134