1 /*
2 * Copyright (C) 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
17 #include "descriptors.h"
18
19 #include <ctype.h>
20 #include <fcntl.h>
21 #include <sys/stat.h>
22 #include <sys/types.h>
23 #include <unistd.h>
24
25 #include <android-base/stringprintf.h>
26 #include <android-base/unique_fd.h>
27 #include <cutils/android_get_control_file.h>
28 #include <cutils/sockets.h>
29
30 #include "init.h"
31 #include "log.h"
32 #include "util.h"
33
DescriptorInfo(const std::string & name,const std::string & type,uid_t uid,gid_t gid,int perm,const std::string & context)34 DescriptorInfo::DescriptorInfo(const std::string& name, const std::string& type, uid_t uid,
35 gid_t gid, int perm, const std::string& context)
36 : name_(name), type_(type), uid_(uid), gid_(gid), perm_(perm), context_(context) {
37 }
38
~DescriptorInfo()39 DescriptorInfo::~DescriptorInfo() {
40 }
41
operator <<(std::ostream & os,const DescriptorInfo & info)42 std::ostream& operator<<(std::ostream& os, const DescriptorInfo& info) {
43 return os << " descriptors " << info.name_ << " " << info.type_ << " " << std::oct << info.perm_;
44 }
45
operator ==(const DescriptorInfo & other) const46 bool DescriptorInfo::operator==(const DescriptorInfo& other) const {
47 return name_ == other.name_ && type_ == other.type_ && key() == other.key();
48 }
49
CreateAndPublish(const std::string & globalContext) const50 void DescriptorInfo::CreateAndPublish(const std::string& globalContext) const {
51 // Create
52 const std::string& contextStr = context_.empty() ? globalContext : context_;
53 int fd = Create(contextStr);
54 if (fd < 0) return;
55
56 // Publish
57 std::string publishedName = key() + name_;
58 std::for_each(publishedName.begin(), publishedName.end(),
59 [] (char& c) { c = isalnum(c) ? c : '_'; });
60
61 std::string val = android::base::StringPrintf("%d", fd);
62 add_environment(publishedName.c_str(), val.c_str());
63
64 // make sure we don't close on exec
65 fcntl(fd, F_SETFD, 0);
66 }
67
Clean() const68 void DescriptorInfo::Clean() const {
69 }
70
SocketInfo(const std::string & name,const std::string & type,uid_t uid,gid_t gid,int perm,const std::string & context)71 SocketInfo::SocketInfo(const std::string& name, const std::string& type, uid_t uid,
72 gid_t gid, int perm, const std::string& context)
73 : DescriptorInfo(name, type, uid, gid, perm, context) {
74 }
75
Clean() const76 void SocketInfo::Clean() const {
77 unlink(android::base::StringPrintf(ANDROID_SOCKET_DIR "/%s", name().c_str()).c_str());
78 }
79
Create(const std::string & context) const80 int SocketInfo::Create(const std::string& context) const {
81 int flags = ((type() == "stream" ? SOCK_STREAM :
82 (type() == "dgram" ? SOCK_DGRAM :
83 SOCK_SEQPACKET)));
84 return create_socket(name().c_str(), flags, perm(), uid(), gid(), context.c_str());
85 }
86
key() const87 const std::string SocketInfo::key() const {
88 return ANDROID_SOCKET_ENV_PREFIX;
89 }
90
FileInfo(const std::string & name,const std::string & type,uid_t uid,gid_t gid,int perm,const std::string & context)91 FileInfo::FileInfo(const std::string& name, const std::string& type, uid_t uid,
92 gid_t gid, int perm, const std::string& context)
93 // defaults OK for uid,..., they are ignored for this class.
94 : DescriptorInfo(name, type, uid, gid, perm, context) {
95 }
96
Create(const std::string &) const97 int FileInfo::Create(const std::string&) const {
98 int flags = (type() == "r") ? O_RDONLY :
99 (type() == "w") ? O_WRONLY :
100 O_RDWR;
101
102 // Make sure we do not block on open (eg: devices can chose to block on
103 // carrier detect). Our intention is never to delay launch of a service
104 // for such a condition. The service can perform its own blocking on
105 // carrier detect.
106 android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(name().c_str(),
107 flags | O_NONBLOCK)));
108
109 if (fd < 0) {
110 PLOG(ERROR) << "Failed to open file '" << name().c_str() << "'";
111 return -1;
112 }
113
114 // Fixup as we set O_NONBLOCK for open, the intent for fd is to block reads.
115 fcntl(fd, F_SETFL, flags);
116
117 LOG(INFO) << "Opened file '" << name().c_str() << "'"
118 << ", flags " << std::oct << flags << std::dec;
119
120 return fd.release();
121 }
122
key() const123 const std::string FileInfo::key() const {
124 return ANDROID_FILE_ENV_PREFIX;
125 }
126