init: service file keyword
Solve one more issue where privilege is required to open a file and
we do not want to grant such to the service. This is the service side
of the picture, android_get_control_file() in libcutils is the client.
The file's descriptor is placed into the environment as
"ANDROID_FILE_<path>". For socket and files where non-alpha and
non-numeric characters in the <name/path> are replaced with _. There
was an accompanying change in android_get_control_socket() to match
in commit 'libcutils: add android_get_control_socket() test'
Add a gTest unit test for this that tests create_file and
android_get_control_file().
Test: gTest init_tests --gtest_filter=util.create_file
Bug: 32450474
Change-Id: I96eb970c707db6d51a9885873329ba1cb1f23140
diff --git a/init/descriptors.cpp b/init/descriptors.cpp
new file mode 100644
index 0000000..10aae88
--- /dev/null
+++ b/init/descriptors.cpp
@@ -0,0 +1,104 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "descriptors.h"
+
+#include <ctype.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <android-base/stringprintf.h>
+#include <cutils/files.h>
+#include <cutils/sockets.h>
+
+#include "init.h"
+#include "log.h"
+#include "util.h"
+
+DescriptorInfo::DescriptorInfo(const std::string& name, const std::string& type, uid_t uid,
+ gid_t gid, int perm, const std::string& context)
+ : name_(name), type_(type), uid_(uid), gid_(gid), perm_(perm), context_(context) {
+}
+
+DescriptorInfo::~DescriptorInfo() {
+}
+
+std::ostream& operator<<(std::ostream& os, const DescriptorInfo& info) {
+ return os << " descriptors " << info.name_ << " " << info.type_ << " " << std::oct << info.perm_;
+}
+
+bool DescriptorInfo::operator==(const DescriptorInfo& other) const {
+ return name_ == other.name_ && type_ == other.type_ && key() == other.key();
+}
+
+void DescriptorInfo::CreateAndPublish(const std::string& globalContext) const {
+ // Create
+ const std::string& contextStr = context_.empty() ? globalContext : context_;
+ int fd = Create(contextStr);
+ if (fd < 0) return;
+
+ // Publish
+ std::string publishedName = key() + name_;
+ std::for_each(publishedName.begin(), publishedName.end(),
+ [] (char& c) { c = isalnum(c) ? c : '_'; });
+
+ std::string val = android::base::StringPrintf("%d", fd);
+ add_environment(publishedName.c_str(), val.c_str());
+
+ // make sure we don't close on exec
+ fcntl(fd, F_SETFD, 0);
+}
+
+void DescriptorInfo::Clean() const {
+}
+
+SocketInfo::SocketInfo(const std::string& name, const std::string& type, uid_t uid,
+ gid_t gid, int perm, const std::string& context)
+ : DescriptorInfo(name, type, uid, gid, perm, context) {
+}
+
+void SocketInfo::Clean() const {
+ unlink(android::base::StringPrintf(ANDROID_SOCKET_DIR "/%s", name().c_str()).c_str());
+}
+
+int SocketInfo::Create(const std::string& context) const {
+ int flags = ((type() == "stream" ? SOCK_STREAM :
+ (type() == "dgram" ? SOCK_DGRAM :
+ SOCK_SEQPACKET)));
+ return create_socket(name().c_str(), flags, perm(), uid(), gid(), context.c_str());
+}
+
+const std::string SocketInfo::key() const {
+ return ANDROID_SOCKET_ENV_PREFIX;
+}
+
+FileInfo::FileInfo(const std::string& name, const std::string& type, uid_t uid,
+ gid_t gid, int perm, const std::string& context)
+ : DescriptorInfo(name, type, uid, gid, perm, context) {
+}
+
+int FileInfo::Create(const std::string& context) const {
+ int flags = ((type() == "r" ? O_RDONLY :
+ (type() == "w" ? (O_WRONLY | O_CREAT) :
+ (O_RDWR | O_CREAT))));
+ return create_file(name().c_str(), flags, perm(), uid(), gid(), context.c_str());
+}
+
+const std::string FileInfo::key() const {
+ return ANDROID_FILE_ENV_PREFIX;
+}