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 <fcntl.h>
18 #include <string.h>
19 #include <sys/wait.h>
20
21 #define LOG_TAG "Netd"
22
23 #include <cutils/log.h>
24 #include <logwrap/logwrap.h>
25
26 #include "NetdConstants.h"
27
28 const char * const OEM_SCRIPT_PATH = "/system/bin/oem-iptables-init.sh";
29 const char * const IPTABLES_PATH = "/system/bin/iptables";
30 const char * const IP6TABLES_PATH = "/system/bin/ip6tables";
31 const char * const TC_PATH = "/system/bin/tc";
32 const char * const IP_PATH = "/system/bin/ip";
33 const char * const ADD = "add";
34 const char * const DEL = "del";
35
logExecError(const char * argv[],int res,int status)36 static void logExecError(const char* argv[], int res, int status) {
37 const char** argp = argv;
38 std::string args = "";
39 while (*argp) {
40 args += *argp;
41 args += ' ';
42 argp++;
43 }
44 ALOGE("exec() res=%d, status=%d for %s", res, status, args.c_str());
45 }
46
execIptablesCommand(int argc,const char * argv[],bool silent)47 static int execIptablesCommand(int argc, const char *argv[], bool silent) {
48 int res;
49 int status;
50
51 res = android_fork_execvp(argc, (char **)argv, &status, false,
52 !silent);
53 if (res || !WIFEXITED(status) || WEXITSTATUS(status)) {
54 if (!silent) {
55 logExecError(argv, res, status);
56 }
57 if (res)
58 return res;
59 if (!WIFEXITED(status))
60 return ECHILD;
61 }
62 return WEXITSTATUS(status);
63 }
64
execIptables(IptablesTarget target,bool silent,va_list args)65 static int execIptables(IptablesTarget target, bool silent, va_list args) {
66 /* Read arguments from incoming va_list; we expect the list to be NULL terminated. */
67 std::list<const char*> argsList;
68 argsList.push_back(NULL);
69 const char* arg;
70 do {
71 arg = va_arg(args, const char *);
72 argsList.push_back(arg);
73 } while (arg);
74
75 int i = 0;
76 const char* argv[argsList.size()];
77 std::list<const char*>::iterator it;
78 for (it = argsList.begin(); it != argsList.end(); it++, i++) {
79 argv[i] = *it;
80 }
81
82 int res = 0;
83 if (target == V4 || target == V4V6) {
84 argv[0] = IPTABLES_PATH;
85 res |= execIptablesCommand(argsList.size(), argv, silent);
86 }
87 if (target == V6 || target == V4V6) {
88 argv[0] = IP6TABLES_PATH;
89 res |= execIptablesCommand(argsList.size(), argv, silent);
90 }
91 return res;
92 }
93
execIptables(IptablesTarget target,...)94 int execIptables(IptablesTarget target, ...) {
95 va_list args;
96 va_start(args, target);
97 int res = execIptables(target, false, args);
98 va_end(args);
99 return res;
100 }
101
execIptablesSilently(IptablesTarget target,...)102 int execIptablesSilently(IptablesTarget target, ...) {
103 va_list args;
104 va_start(args, target);
105 int res = execIptables(target, true, args);
106 va_end(args);
107 return res;
108 }
109
writeFile(const char * path,const char * value,int size)110 int writeFile(const char *path, const char *value, int size) {
111 int fd = open(path, O_WRONLY);
112 if (fd < 0) {
113 ALOGE("Failed to open %s: %s", path, strerror(errno));
114 return -1;
115 }
116
117 if (write(fd, value, size) != size) {
118 ALOGE("Failed to write %s: %s", path, strerror(errno));
119 close(fd);
120 return -1;
121 }
122 close(fd);
123 return 0;
124 }
125
readFile(const char * path,char * buf,int * sizep)126 int readFile(const char *path, char *buf, int *sizep)
127 {
128 int fd = open(path, O_RDONLY);
129 int size;
130
131 if (fd < 0) {
132 ALOGE("Failed to open %s: %s", path, strerror(errno));
133 return -1;
134 }
135
136 size = read(fd, buf, *sizep);
137 if (size < 0) {
138 ALOGE("Failed to write %s: %s", path, strerror(errno));
139 close(fd);
140 return -1;
141 }
142 *sizep = size;
143 close(fd);
144 return 0;
145 }
146