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-rw-r--r--dom/media/gmp/GMPDiskStorage.cpp499
1 files changed, 499 insertions, 0 deletions
diff --git a/dom/media/gmp/GMPDiskStorage.cpp b/dom/media/gmp/GMPDiskStorage.cpp
new file mode 100644
index 000000000..11f49c8fe
--- /dev/null
+++ b/dom/media/gmp/GMPDiskStorage.cpp
@@ -0,0 +1,499 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "plhash.h"
+#include "nsDirectoryServiceUtils.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsAppDirectoryServiceDefs.h"
+#include "GMPParent.h"
+#include "gmp-storage.h"
+#include "mozilla/Unused.h"
+#include "mozilla/EndianUtils.h"
+#include "nsClassHashtable.h"
+#include "prio.h"
+#include "mozIGeckoMediaPluginService.h"
+#include "nsContentCID.h"
+#include "nsServiceManagerUtils.h"
+#include "nsISimpleEnumerator.h"
+
+namespace mozilla {
+
+#ifdef LOG
+#undef LOG
+#endif
+
+extern LogModule* GetGMPLog();
+
+#define LOGD(msg) MOZ_LOG(GetGMPLog(), mozilla::LogLevel::Debug, msg)
+#define LOG(level, msg) MOZ_LOG(GetGMPLog(), (level), msg)
+
+namespace gmp {
+
+// We store the records for a given GMP as files in the profile dir.
+// $profileDir/gmp/$platform/$gmpName/storage/$nodeId/
+static nsresult
+GetGMPStorageDir(nsIFile** aTempDir,
+ const nsString& aGMPName,
+ const nsCString& aNodeId)
+{
+ if (NS_WARN_IF(!aTempDir)) {
+ return NS_ERROR_INVALID_ARG;
+ }
+
+ nsCOMPtr<mozIGeckoMediaPluginChromeService> mps =
+ do_GetService("@mozilla.org/gecko-media-plugin-service;1");
+ if (NS_WARN_IF(!mps)) {
+ return NS_ERROR_FAILURE;
+ }
+
+ nsCOMPtr<nsIFile> tmpFile;
+ nsresult rv = mps->GetStorageDir(getter_AddRefs(tmpFile));
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ rv = tmpFile->Append(aGMPName);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ rv = tmpFile->Create(nsIFile::DIRECTORY_TYPE, 0700);
+ if (rv != NS_ERROR_FILE_ALREADY_EXISTS && NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ rv = tmpFile->AppendNative(NS_LITERAL_CSTRING("storage"));
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ rv = tmpFile->Create(nsIFile::DIRECTORY_TYPE, 0700);
+ if (rv != NS_ERROR_FILE_ALREADY_EXISTS && NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ rv = tmpFile->AppendNative(aNodeId);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ rv = tmpFile->Create(nsIFile::DIRECTORY_TYPE, 0700);
+ if (rv != NS_ERROR_FILE_ALREADY_EXISTS && NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ tmpFile.forget(aTempDir);
+
+ return NS_OK;
+}
+
+// Disk-backed GMP storage. Records are stored in files on disk in
+// the profile directory. The record name is a hash of the filename,
+// and we resolve hash collisions by just adding 1 to the hash code.
+// The format of records on disk is:
+// 4 byte, uint32_t $recordNameLength, in little-endian byte order,
+// record name (i.e. $recordNameLength bytes, no null terminator)
+// record bytes (entire remainder of file)
+class GMPDiskStorage : public GMPStorage {
+public:
+ explicit GMPDiskStorage(const nsCString& aNodeId,
+ const nsString& aGMPName)
+ : mNodeId(aNodeId)
+ , mGMPName(aGMPName)
+ {
+ }
+
+ ~GMPDiskStorage() {
+ // Close all open file handles.
+ for (auto iter = mRecords.ConstIter(); !iter.Done(); iter.Next()) {
+ Record* record = iter.UserData();
+ if (record->mFileDesc) {
+ PR_Close(record->mFileDesc);
+ record->mFileDesc = nullptr;
+ }
+ }
+ }
+
+ nsresult Init() {
+ // Build our index of records on disk.
+ nsCOMPtr<nsIFile> storageDir;
+ nsresult rv = GetGMPStorageDir(getter_AddRefs(storageDir), mGMPName, mNodeId);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return NS_ERROR_FAILURE;
+ }
+
+ DirectoryEnumerator iter(storageDir, DirectoryEnumerator::FilesAndDirs);
+ for (nsCOMPtr<nsIFile> dirEntry; (dirEntry = iter.Next()) != nullptr;) {
+ PRFileDesc* fd = nullptr;
+ if (NS_FAILED(dirEntry->OpenNSPRFileDesc(PR_RDONLY, 0, &fd))) {
+ continue;
+ }
+ int32_t recordLength = 0;
+ nsCString recordName;
+ nsresult err = ReadRecordMetadata(fd, recordLength, recordName);
+ PR_Close(fd);
+ if (NS_FAILED(err)) {
+ // File is not a valid storage file. Don't index it. Delete the file,
+ // to make our indexing faster in future.
+ dirEntry->Remove(false);
+ continue;
+ }
+
+ nsAutoString filename;
+ rv = dirEntry->GetLeafName(filename);
+ if (NS_FAILED(rv)) {
+ continue;
+ }
+
+ mRecords.Put(recordName, new Record(filename, recordName));
+ }
+
+ return NS_OK;
+ }
+
+ GMPErr Open(const nsCString& aRecordName) override
+ {
+ MOZ_ASSERT(!IsOpen(aRecordName));
+ nsresult rv;
+ Record* record = nullptr;
+ if (!mRecords.Get(aRecordName, &record)) {
+ // New file.
+ nsAutoString filename;
+ rv = GetUnusedFilename(aRecordName, filename);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return GMPGenericErr;
+ }
+ record = new Record(filename, aRecordName);
+ mRecords.Put(aRecordName, record);
+ }
+
+ MOZ_ASSERT(record);
+ if (record->mFileDesc) {
+ NS_WARNING("Tried to open already open record");
+ return GMPRecordInUse;
+ }
+
+ rv = OpenStorageFile(record->mFilename, ReadWrite, &record->mFileDesc);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return GMPGenericErr;
+ }
+
+ MOZ_ASSERT(IsOpen(aRecordName));
+
+ return GMPNoErr;
+ }
+
+ bool IsOpen(const nsCString& aRecordName) const override {
+ // We are open if we have a record indexed, and it has a valid
+ // file descriptor.
+ const Record* record = mRecords.Get(aRecordName);
+ return record && !!record->mFileDesc;
+ }
+
+ GMPErr Read(const nsCString& aRecordName,
+ nsTArray<uint8_t>& aOutBytes) override
+ {
+ if (!IsOpen(aRecordName)) {
+ return GMPClosedErr;
+ }
+
+ Record* record = nullptr;
+ mRecords.Get(aRecordName, &record);
+ MOZ_ASSERT(record && !!record->mFileDesc); // IsOpen() guarantees this.
+
+ // Our error strategy is to report records with invalid contents as
+ // containing 0 bytes. Zero length records are considered "deleted" by
+ // the GMPStorage API.
+ aOutBytes.SetLength(0);
+
+ int32_t recordLength = 0;
+ nsCString recordName;
+ nsresult err = ReadRecordMetadata(record->mFileDesc,
+ recordLength,
+ recordName);
+ if (NS_FAILED(err) || recordLength == 0) {
+ // We failed to read the record metadata. Or the record is 0 length.
+ // Treat damaged records as empty.
+ // ReadRecordMetadata() could fail if the GMP opened a new record and
+ // tried to read it before anything was written to it..
+ return GMPNoErr;
+ }
+
+ if (!aRecordName.Equals(recordName)) {
+ NS_WARNING("Record file contains some other record's contents!");
+ return GMPRecordCorrupted;
+ }
+
+ // After calling ReadRecordMetadata, we should be ready to read the
+ // record data.
+ if (PR_Available(record->mFileDesc) != recordLength) {
+ NS_WARNING("Record file length mismatch!");
+ return GMPRecordCorrupted;
+ }
+
+ aOutBytes.SetLength(recordLength);
+ int32_t bytesRead = PR_Read(record->mFileDesc, aOutBytes.Elements(), recordLength);
+ return (bytesRead == recordLength) ? GMPNoErr : GMPRecordCorrupted;
+ }
+
+ GMPErr Write(const nsCString& aRecordName,
+ const nsTArray<uint8_t>& aBytes) override
+ {
+ if (!IsOpen(aRecordName)) {
+ return GMPClosedErr;
+ }
+
+ Record* record = nullptr;
+ mRecords.Get(aRecordName, &record);
+ MOZ_ASSERT(record && !!record->mFileDesc); // IsOpen() guarantees this.
+
+ // Write operations overwrite the entire record. So close it now.
+ PR_Close(record->mFileDesc);
+ record->mFileDesc = nullptr;
+
+ // Writing 0 bytes means removing (deleting) the file.
+ if (aBytes.Length() == 0) {
+ nsresult rv = RemoveStorageFile(record->mFilename);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ // Could not delete file -> Continue with trying to erase the contents.
+ } else {
+ return GMPNoErr;
+ }
+ }
+
+ // Write operations overwrite the entire record. So re-open the file
+ // in truncate mode, to clear its contents.
+ if (NS_FAILED(OpenStorageFile(record->mFilename,
+ Truncate,
+ &record->mFileDesc))) {
+ return GMPGenericErr;
+ }
+
+ // Store the length of the record name followed by the record name
+ // at the start of the file.
+ int32_t bytesWritten = 0;
+ char buf[sizeof(uint32_t)] = {0};
+ LittleEndian::writeUint32(buf, aRecordName.Length());
+ bytesWritten = PR_Write(record->mFileDesc, buf, MOZ_ARRAY_LENGTH(buf));
+ if (bytesWritten != MOZ_ARRAY_LENGTH(buf)) {
+ NS_WARNING("Failed to write GMPStorage record name length.");
+ return GMPRecordCorrupted;
+ }
+ bytesWritten = PR_Write(record->mFileDesc,
+ aRecordName.get(),
+ aRecordName.Length());
+ if (bytesWritten != (int32_t)aRecordName.Length()) {
+ NS_WARNING("Failed to write GMPStorage record name.");
+ return GMPRecordCorrupted;
+ }
+
+ bytesWritten = PR_Write(record->mFileDesc, aBytes.Elements(), aBytes.Length());
+ if (bytesWritten != (int32_t)aBytes.Length()) {
+ NS_WARNING("Failed to write GMPStorage record data.");
+ return GMPRecordCorrupted;
+ }
+
+ // Try to sync the file to disk, so that in the event of a crash,
+ // the record is less likely to be corrupted.
+ PR_Sync(record->mFileDesc);
+
+ return GMPNoErr;
+ }
+
+ GMPErr GetRecordNames(nsTArray<nsCString>& aOutRecordNames) const override
+ {
+ for (auto iter = mRecords.ConstIter(); !iter.Done(); iter.Next()) {
+ aOutRecordNames.AppendElement(iter.UserData()->mRecordName);
+ }
+ return GMPNoErr;
+ }
+
+ void Close(const nsCString& aRecordName) override
+ {
+ Record* record = nullptr;
+ mRecords.Get(aRecordName, &record);
+ if (record && !!record->mFileDesc) {
+ PR_Close(record->mFileDesc);
+ record->mFileDesc = nullptr;
+ }
+ MOZ_ASSERT(!IsOpen(aRecordName));
+ }
+
+private:
+
+ // We store records in a file which is a hash of the record name.
+ // If there is a hash collision, we just keep adding 1 to the hash
+ // code, until we find a free slot.
+ nsresult GetUnusedFilename(const nsACString& aRecordName,
+ nsString& aOutFilename)
+ {
+ nsCOMPtr<nsIFile> storageDir;
+ nsresult rv = GetGMPStorageDir(getter_AddRefs(storageDir), mGMPName, mNodeId);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+
+ uint64_t recordNameHash = HashString(PromiseFlatCString(aRecordName).get());
+ for (int i = 0; i < 1000000; i++) {
+ nsCOMPtr<nsIFile> f;
+ rv = storageDir->Clone(getter_AddRefs(f));
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+ nsAutoString hashStr;
+ hashStr.AppendInt(recordNameHash);
+ rv = f->Append(hashStr);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+ bool exists = false;
+ f->Exists(&exists);
+ if (!exists) {
+ // Filename not in use, we can write into this file.
+ aOutFilename = hashStr;
+ return NS_OK;
+ } else {
+ // Hash collision; just increment the hash name and try that again.
+ ++recordNameHash;
+ continue;
+ }
+ }
+ // Somehow, we've managed to completely fail to find a vacant file name.
+ // Give up.
+ NS_WARNING("GetUnusedFilename had extreme hash collision!");
+ return NS_ERROR_FAILURE;
+ }
+
+ enum OpenFileMode { ReadWrite, Truncate };
+
+ nsresult OpenStorageFile(const nsAString& aFileLeafName,
+ const OpenFileMode aMode,
+ PRFileDesc** aOutFD)
+ {
+ MOZ_ASSERT(aOutFD);
+
+ nsCOMPtr<nsIFile> f;
+ nsresult rv = GetGMPStorageDir(getter_AddRefs(f), mGMPName, mNodeId);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+ f->Append(aFileLeafName);
+
+ auto mode = PR_RDWR | PR_CREATE_FILE;
+ if (aMode == Truncate) {
+ mode |= PR_TRUNCATE;
+ }
+
+ return f->OpenNSPRFileDesc(mode, PR_IRWXU, aOutFD);
+ }
+
+ nsresult ReadRecordMetadata(PRFileDesc* aFd,
+ int32_t& aOutRecordLength,
+ nsACString& aOutRecordName)
+ {
+ int32_t offset = PR_Seek(aFd, 0, PR_SEEK_END);
+ PR_Seek(aFd, 0, PR_SEEK_SET);
+
+ if (offset < 0 || offset > GMP_MAX_RECORD_SIZE) {
+ // Refuse to read big records, or records where we can't get a length.
+ return NS_ERROR_FAILURE;
+ }
+ const uint32_t fileLength = static_cast<uint32_t>(offset);
+
+ // At the start of the file the length of the record name is stored in a
+ // uint32_t (little endian byte order) followed by the record name at the
+ // start of the file. The record name is not null terminated. The remainder
+ // of the file is the record's data.
+
+ if (fileLength < sizeof(uint32_t)) {
+ // Record file doesn't have enough contents to store the record name
+ // length. Fail.
+ return NS_ERROR_FAILURE;
+ }
+
+ // Read length, and convert to host byte order.
+ uint32_t recordNameLength = 0;
+ char buf[sizeof(recordNameLength)] = { 0 };
+ int32_t bytesRead = PR_Read(aFd, &buf, sizeof(recordNameLength));
+ recordNameLength = LittleEndian::readUint32(buf);
+ if (sizeof(recordNameLength) != bytesRead ||
+ recordNameLength == 0 ||
+ recordNameLength + sizeof(recordNameLength) > fileLength ||
+ recordNameLength > GMP_MAX_RECORD_NAME_SIZE) {
+ // Record file has invalid contents. Fail.
+ return NS_ERROR_FAILURE;
+ }
+
+ nsCString recordName;
+ recordName.SetLength(recordNameLength);
+ bytesRead = PR_Read(aFd, recordName.BeginWriting(), recordNameLength);
+ if ((uint32_t)bytesRead != recordNameLength) {
+ // Read failed.
+ return NS_ERROR_FAILURE;
+ }
+
+ MOZ_ASSERT(fileLength >= sizeof(recordNameLength) + recordNameLength);
+ int32_t recordLength = fileLength - (sizeof(recordNameLength) + recordNameLength);
+
+ aOutRecordLength = recordLength;
+ aOutRecordName = recordName;
+
+ // Read cursor should be positioned after the record name, before the record contents.
+ if (PR_Seek(aFd, 0, PR_SEEK_CUR) != (int32_t)(sizeof(recordNameLength) + recordNameLength)) {
+ NS_WARNING("Read cursor mismatch after ReadRecordMetadata()");
+ return NS_ERROR_FAILURE;
+ }
+
+ return NS_OK;
+ }
+
+ nsresult RemoveStorageFile(const nsString& aFilename)
+ {
+ nsCOMPtr<nsIFile> f;
+ nsresult rv = GetGMPStorageDir(getter_AddRefs(f), mGMPName, mNodeId);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+ rv = f->Append(aFilename);
+ if (NS_WARN_IF(NS_FAILED(rv))) {
+ return rv;
+ }
+ return f->Remove(/* bool recursive= */ false);
+ }
+
+ struct Record {
+ Record(const nsAString& aFilename,
+ const nsACString& aRecordName)
+ : mFilename(aFilename)
+ , mRecordName(aRecordName)
+ , mFileDesc(0)
+ {}
+ ~Record() {
+ MOZ_ASSERT(!mFileDesc);
+ }
+ nsString mFilename;
+ nsCString mRecordName;
+ PRFileDesc* mFileDesc;
+ };
+
+ // Hash record name to record data.
+ nsClassHashtable<nsCStringHashKey, Record> mRecords;
+ const nsCString mNodeId;
+ const nsString mGMPName;
+};
+
+already_AddRefed<GMPStorage> CreateGMPDiskStorage(const nsCString& aNodeId,
+ const nsString& aGMPName)
+{
+ RefPtr<GMPDiskStorage> storage(new GMPDiskStorage(aNodeId, aGMPName));
+ if (NS_FAILED(storage->Init())) {
+ NS_WARNING("Failed to initialize on disk GMP storage");
+ return nullptr;
+ }
+ return storage.forget();
+}
+
+} // namespace gmp
+} // namespace mozilla