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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: sw=2 ts=4 et :
* 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 "GMPLoader.h"
#include <stdio.h>
#include "mozilla/Attributes.h"
#include "nsExceptionHandler.h"
#include "gmp-entrypoints.h"
#include "prlink.h"
#include "prenv.h"
#include "prerror.h"
#if defined(XP_WIN) && defined(MOZ_SANDBOX)
# include "mozilla/sandboxTarget.h"
# include "mozilla/sandboxing/SandboxInitialization.h"
# include "mozilla/sandboxing/sandboxLogging.h"
#endif
#if defined(XP_LINUX) && defined(MOZ_SANDBOX)
# include "mozilla/Sandbox.h"
# include "mozilla/SandboxInfo.h"
#endif
#include <string>
#ifdef XP_WIN
# include <windows.h>
#endif
namespace mozilla::gmp {
class PassThroughGMPAdapter : public GMPAdapter {
public:
~PassThroughGMPAdapter() override {
// Ensure we're always shutdown, even if caller forgets to call
// GMPShutdown().
GMPShutdown();
}
void SetAdaptee(PRLibrary* aLib) override { mLib = aLib; }
GMPErr GMPInit(const GMPPlatformAPI* aPlatformAPI) override {
if (NS_WARN_IF(!mLib)) {
MOZ_CRASH("Missing library!");
return GMPGenericErr;
}
GMPInitFunc initFunc =
reinterpret_cast<GMPInitFunc>(PR_FindFunctionSymbol(mLib, "GMPInit"));
if (!initFunc) {
MOZ_CRASH("Missing init method!");
return GMPNotImplementedErr;
}
return initFunc(aPlatformAPI);
}
GMPErr GMPGetAPI(const char* aAPIName, void* aHostAPI, void** aPluginAPI,
const nsACString& /* aKeySystem */) override {
if (!mLib) {
return GMPGenericErr;
}
GMPGetAPIFunc getapiFunc = reinterpret_cast<GMPGetAPIFunc>(
PR_FindFunctionSymbol(mLib, "GMPGetAPI"));
if (!getapiFunc) {
return GMPNotImplementedErr;
}
return getapiFunc(aAPIName, aHostAPI, aPluginAPI);
}
void GMPShutdown() override {
if (mLib) {
GMPShutdownFunc shutdownFunc = reinterpret_cast<GMPShutdownFunc>(
PR_FindFunctionSymbol(mLib, "GMPShutdown"));
if (shutdownFunc) {
shutdownFunc();
}
PR_UnloadLibrary(mLib);
mLib = nullptr;
}
}
private:
PRLibrary* mLib = nullptr;
};
bool GMPLoader::Load(const char* aUTF8LibPath, uint32_t aUTF8LibPathLen,
const GMPPlatformAPI* aPlatformAPI, GMPAdapter* aAdapter) {
CrashReporter::AutoRecordAnnotation autoLibPath(
CrashReporter::Annotation::GMPLibraryPath,
nsDependentCString(aUTF8LibPath));
if (!getenv("MOZ_DISABLE_GMP_SANDBOX") && mSandboxStarter &&
!mSandboxStarter->Start(aUTF8LibPath)) {
MOZ_CRASH("Cannot start sandbox!");
return false;
}
// Load the GMP.
PRLibSpec libSpec;
#ifdef XP_WIN
int pathLen = MultiByteToWideChar(CP_UTF8, 0, aUTF8LibPath, -1, nullptr, 0);
if (pathLen == 0) {
MOZ_CRASH("Cannot get path length as wide char!");
return false;
}
auto widePath = MakeUnique<wchar_t[]>(pathLen);
if (MultiByteToWideChar(CP_UTF8, 0, aUTF8LibPath, -1, widePath.get(),
pathLen) == 0) {
MOZ_CRASH("Cannot convert path to wide char!");
return false;
}
libSpec.value.pathname_u = widePath.get();
libSpec.type = PR_LibSpec_PathnameU;
#else
libSpec.value.pathname = aUTF8LibPath;
libSpec.type = PR_LibSpec_Pathname;
#endif
PRLibrary* lib = PR_LoadLibraryWithFlags(libSpec, 0);
if (!lib) {
MOZ_CRASH_UNSAFE_PRINTF("Cannot load plugin as library %d %d",
PR_GetError(), PR_GetOSError());
return false;
}
mAdapter.reset((!aAdapter) ? new PassThroughGMPAdapter() : aAdapter);
mAdapter->SetAdaptee(lib);
if (mAdapter->GMPInit(aPlatformAPI) != GMPNoErr) {
MOZ_CRASH("Cannot initialize plugin adapter!");
return false;
}
return true;
}
GMPErr GMPLoader::GetAPI(const char* aAPIName, void* aHostAPI,
void** aPluginAPI, const nsACString& aKeySystem) {
return mAdapter->GMPGetAPI(aAPIName, aHostAPI, aPluginAPI, aKeySystem);
}
void GMPLoader::Shutdown() {
if (mAdapter) {
mAdapter->GMPShutdown();
}
}
#if defined(XP_WIN) && defined(MOZ_SANDBOX)
class WinSandboxStarter : public mozilla::gmp::SandboxStarter {
public:
bool Start(const char* aLibPath) override {
// Cause advapi32 to load before the sandbox is turned on, as
// Widevine version 970 and later require it and the sandbox
// blocks it on Win7.
unsigned int dummy_rand;
rand_s(&dummy_rand);
mozilla::SandboxTarget::Instance()->StartSandbox();
return true;
}
};
#endif
#if defined(XP_LINUX) && defined(MOZ_SANDBOX)
namespace {
class LinuxSandboxStarter : public mozilla::gmp::SandboxStarter {
private:
LinuxSandboxStarter() = default;
friend mozilla::detail::UniqueSelector<LinuxSandboxStarter>::SingleObject
mozilla::MakeUnique<LinuxSandboxStarter>();
public:
static UniquePtr<SandboxStarter> Make() {
if (mozilla::SandboxInfo::Get().CanSandboxMedia()) {
return MakeUnique<LinuxSandboxStarter>();
}
// Sandboxing isn't possible, but the parent has already
// checked that this plugin doesn't require it. (Bug 1074561)
return nullptr;
}
bool Start(const char* aLibPath) override {
mozilla::SetMediaPluginSandbox(aLibPath);
return true;
}
};
} // anonymous namespace
#endif // XP_LINUX && MOZ_SANDBOX
static UniquePtr<SandboxStarter> MakeSandboxStarter() {
#if defined(XP_WIN) && defined(MOZ_SANDBOX)
return mozilla::MakeUnique<WinSandboxStarter>();
#elif defined(XP_LINUX) && defined(MOZ_SANDBOX)
return LinuxSandboxStarter::Make();
#else
return nullptr;
#endif
}
GMPLoader::GMPLoader() : mSandboxStarter(MakeSandboxStarter()) {}
bool GMPLoader::CanSandbox() const { return !!mSandboxStarter; }
} // namespace mozilla::gmp