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 #pragma once
18 
19 #include <ifaddrs.h>
20 #include <netdb.h>
21 #include <stddef.h>
22 #include <stdint.h>
23 
24 #include <mutex>
25 #include <string>
26 
27 #include <netdutils/UidConstants.h>
28 #include <private/android_filesystem_config.h>
29 
30 enum IptablesTarget { V4, V6, V4V6 };
31 
32 int execIptablesRestore(IptablesTarget target, const std::string& commands);
33 int execIptablesRestoreWithOutput(IptablesTarget target, const std::string& commands,
34                                   std::string *output);
35 int execIptablesRestoreCommand(IptablesTarget target, const std::string& table,
36                                const std::string& command, std::string *output);
37 bool isIfaceName(const std::string& name);
38 int parsePrefix(const char *prefix, uint8_t *family, void *address, int size, uint8_t *prefixlen);
39 void blockSigpipe();
40 void setCloseOnExec(const char *sock);
41 
42 // TODO: use std::size() instead.
43 #define ARRAY_SIZE(a) (sizeof(a) / sizeof(*(a)))
44 
45 #define __INT_STRLEN(i) sizeof(#i)
46 #define _INT_STRLEN(i) __INT_STRLEN(i)
47 #define INT32_STRLEN _INT_STRLEN(INT32_MIN)
48 #define UINT32_STRLEN _INT_STRLEN(UINT32_MAX)
49 #define UINT32_HEX_STRLEN sizeof("0x12345678")
50 #define IPSEC_IFACE_PREFIX "ipsec"
51 
52 const uid_t INVALID_UID = static_cast<uid_t>(-1);
53 
54 constexpr char TCP_RMEM_PROC_FILE[] = "/proc/sys/net/ipv4/tcp_rmem";
55 constexpr char TCP_WMEM_PROC_FILE[] = "/proc/sys/net/ipv4/tcp_wmem";
56 
57 struct IfaddrsDeleter {
operatorIfaddrsDeleter58     void operator()(struct ifaddrs *p) const {
59         if (p != nullptr) {
60             freeifaddrs(p);
61         }
62     }
63 };
64 
65 typedef std::unique_ptr<struct ifaddrs, struct IfaddrsDeleter> ScopedIfaddrs;
66 
67 namespace android::net {
68 
69 /**
70  * This lock exists to make NetdNativeService RPCs (which come in on multiple Binder threads)
71  * coexist with the commands in CommandListener.cpp. These are presumed not thread-safe because
72  * CommandListener has only one user (NetworkManagementService), which is connected through a
73  * FrameworkListener that passes in commands one at a time.
74  */
75 extern std::mutex gBigNetdLock;
76 
77 }  // namespace android::net
78