OLD | NEW |
| (Empty) |
1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. | |
2 // Use of this source code is governed by a BSD-style license that can be | |
3 // found in the LICENSE file. | |
4 | |
5 #include "chrome/nacl/nacl_listener.h" | |
6 | |
7 #include <errno.h> | |
8 #include <stdlib.h> | |
9 | |
10 #if defined(OS_POSIX) | |
11 #include <unistd.h> | |
12 #endif | |
13 | |
14 #include "base/command_line.h" | |
15 #include "base/logging.h" | |
16 #include "base/memory/scoped_ptr.h" | |
17 #include "base/message_loop.h" | |
18 #include "base/rand_util.h" | |
19 #include "chrome/common/nacl_messages.h" | |
20 #include "chrome/nacl/nacl_ipc_adapter.h" | |
21 #include "chrome/nacl/nacl_validation_db.h" | |
22 #include "chrome/nacl/nacl_validation_query.h" | |
23 #include "ipc/ipc_channel_handle.h" | |
24 #include "ipc/ipc_switches.h" | |
25 #include "ipc/ipc_sync_channel.h" | |
26 #include "ipc/ipc_sync_message_filter.h" | |
27 #include "native_client/src/trusted/service_runtime/sel_main_chrome.h" | |
28 #include "native_client/src/trusted/validator/nacl_file_info.h" | |
29 | |
30 #if defined(OS_POSIX) | |
31 #include "base/file_descriptor_posix.h" | |
32 #endif | |
33 | |
34 #if defined(OS_LINUX) | |
35 #include "content/public/common/child_process_sandbox_support_linux.h" | |
36 #endif | |
37 | |
38 #if defined(OS_WIN) | |
39 #include <fcntl.h> | |
40 #include <io.h> | |
41 | |
42 #include "content/public/common/sandbox_init.h" | |
43 #endif | |
44 | |
45 namespace { | |
46 #if defined(OS_MACOSX) | |
47 | |
48 // On Mac OS X, shm_open() works in the sandbox but does not give us | |
49 // an FD that we can map as PROT_EXEC. Rather than doing an IPC to | |
50 // get an executable SHM region when CreateMemoryObject() is called, | |
51 // we preallocate one on startup, since NaCl's sel_ldr only needs one | |
52 // of them. This saves a round trip. | |
53 | |
54 base::subtle::Atomic32 g_shm_fd = -1; | |
55 | |
56 int CreateMemoryObject(size_t size, int executable) { | |
57 if (executable && size > 0) { | |
58 int result_fd = base::subtle::NoBarrier_AtomicExchange(&g_shm_fd, -1); | |
59 if (result_fd != -1) { | |
60 // ftruncate() is disallowed by the Mac OS X sandbox and | |
61 // returns EPERM. Luckily, we can get the same effect with | |
62 // lseek() + write(). | |
63 if (lseek(result_fd, size - 1, SEEK_SET) == -1) { | |
64 LOG(ERROR) << "lseek() failed: " << errno; | |
65 return -1; | |
66 } | |
67 if (write(result_fd, "", 1) != 1) { | |
68 LOG(ERROR) << "write() failed: " << errno; | |
69 return -1; | |
70 } | |
71 return result_fd; | |
72 } | |
73 } | |
74 // Fall back to NaCl's default implementation. | |
75 return -1; | |
76 } | |
77 | |
78 #elif defined(OS_LINUX) | |
79 | |
80 int CreateMemoryObject(size_t size, int executable) { | |
81 return content::MakeSharedMemorySegmentViaIPC(size, executable); | |
82 } | |
83 | |
84 #elif defined(OS_WIN) | |
85 | |
86 NaClListener* g_listener; | |
87 | |
88 // We wrap the function to convert the bool return value to an int. | |
89 int BrokerDuplicateHandle(NaClHandle source_handle, | |
90 uint32_t process_id, | |
91 NaClHandle* target_handle, | |
92 uint32_t desired_access, | |
93 uint32_t options) { | |
94 return content::BrokerDuplicateHandle(source_handle, process_id, | |
95 target_handle, desired_access, | |
96 options); | |
97 } | |
98 | |
99 int AttachDebugExceptionHandler(const void* info, size_t info_size) { | |
100 std::string info_string(reinterpret_cast<const char*>(info), info_size); | |
101 bool result = false; | |
102 if (!g_listener->Send(new NaClProcessMsg_AttachDebugExceptionHandler( | |
103 info_string, &result))) | |
104 return false; | |
105 return result; | |
106 } | |
107 | |
108 #endif | |
109 | |
110 } // namespace | |
111 | |
112 class BrowserValidationDBProxy : public NaClValidationDB { | |
113 public: | |
114 explicit BrowserValidationDBProxy(NaClListener* listener) | |
115 : listener_(listener) { | |
116 } | |
117 | |
118 virtual bool QueryKnownToValidate(const std::string& signature) OVERRIDE { | |
119 // Initialize to false so that if the Send fails to write to the return | |
120 // value we're safe. For example if the message is (for some reason) | |
121 // dispatched as an async message the return parameter will not be written. | |
122 bool result = false; | |
123 if (!listener_->Send(new NaClProcessMsg_QueryKnownToValidate(signature, | |
124 &result))) { | |
125 LOG(ERROR) << "Failed to query NaCl validation cache."; | |
126 result = false; | |
127 } | |
128 return result; | |
129 } | |
130 | |
131 virtual void SetKnownToValidate(const std::string& signature) OVERRIDE { | |
132 // Caching is optional: NaCl will still work correctly if the IPC fails. | |
133 if (!listener_->Send(new NaClProcessMsg_SetKnownToValidate(signature))) { | |
134 LOG(ERROR) << "Failed to update NaCl validation cache."; | |
135 } | |
136 } | |
137 | |
138 virtual bool ResolveFileToken(struct NaClFileToken* file_token, | |
139 int32* fd, std::string* path) OVERRIDE { | |
140 *fd = -1; | |
141 *path = ""; | |
142 if (file_token->lo == 0 && file_token->hi == 0) { | |
143 return false; | |
144 } | |
145 IPC::PlatformFileForTransit ipc_fd = IPC::InvalidPlatformFileForTransit(); | |
146 base::FilePath ipc_path; | |
147 if (!listener_->Send(new NaClProcessMsg_ResolveFileToken(file_token->lo, | |
148 file_token->hi, | |
149 &ipc_fd, | |
150 &ipc_path))) { | |
151 return false; | |
152 } | |
153 if (ipc_fd == IPC::InvalidPlatformFileForTransit()) { | |
154 return false; | |
155 } | |
156 base::PlatformFile handle = | |
157 IPC::PlatformFileForTransitToPlatformFile(ipc_fd); | |
158 #if defined(OS_WIN) | |
159 // On Windows, valid handles are 32 bit unsigned integers so this is safe. | |
160 *fd = reinterpret_cast<uintptr_t>(handle); | |
161 #else | |
162 *fd = handle; | |
163 #endif | |
164 // It doesn't matter if the path is invalid UTF8 as long as it's consistent | |
165 // and unforgeable. | |
166 *path = ipc_path.AsUTF8Unsafe(); | |
167 return true; | |
168 } | |
169 | |
170 private: | |
171 // The listener never dies, otherwise this might be a dangling reference. | |
172 NaClListener* listener_; | |
173 }; | |
174 | |
175 | |
176 NaClListener::NaClListener() : shutdown_event_(true, false), | |
177 io_thread_("NaCl_IOThread"), | |
178 #if defined(OS_LINUX) | |
179 prereserved_sandbox_size_(0), | |
180 #endif | |
181 #if defined(OS_POSIX) | |
182 number_of_cores_(-1), // unknown/error | |
183 #endif | |
184 main_loop_(NULL) { | |
185 io_thread_.StartWithOptions( | |
186 base::Thread::Options(base::MessageLoop::TYPE_IO, 0)); | |
187 #if defined(OS_WIN) | |
188 DCHECK(g_listener == NULL); | |
189 g_listener = this; | |
190 #endif | |
191 } | |
192 | |
193 NaClListener::~NaClListener() { | |
194 NOTREACHED(); | |
195 shutdown_event_.Signal(); | |
196 #if defined(OS_WIN) | |
197 g_listener = NULL; | |
198 #endif | |
199 } | |
200 | |
201 bool NaClListener::Send(IPC::Message* msg) { | |
202 DCHECK(main_loop_ != NULL); | |
203 if (base::MessageLoop::current() == main_loop_) { | |
204 // This thread owns the channel. | |
205 return channel_->Send(msg); | |
206 } else { | |
207 // This thread does not own the channel. | |
208 return filter_->Send(msg); | |
209 } | |
210 } | |
211 | |
212 void NaClListener::Listen() { | |
213 std::string channel_name = | |
214 CommandLine::ForCurrentProcess()->GetSwitchValueASCII( | |
215 switches::kProcessChannelID); | |
216 channel_.reset(new IPC::SyncChannel( | |
217 this, io_thread_.message_loop_proxy().get(), &shutdown_event_)); | |
218 filter_ = new IPC::SyncMessageFilter(&shutdown_event_); | |
219 channel_->AddFilter(filter_.get()); | |
220 channel_->Init(channel_name, IPC::Channel::MODE_CLIENT, true); | |
221 main_loop_ = base::MessageLoop::current(); | |
222 main_loop_->Run(); | |
223 } | |
224 | |
225 bool NaClListener::OnMessageReceived(const IPC::Message& msg) { | |
226 bool handled = true; | |
227 IPC_BEGIN_MESSAGE_MAP(NaClListener, msg) | |
228 IPC_MESSAGE_HANDLER(NaClProcessMsg_Start, OnStart) | |
229 IPC_MESSAGE_UNHANDLED(handled = false) | |
230 IPC_END_MESSAGE_MAP() | |
231 return handled; | |
232 } | |
233 | |
234 void NaClListener::OnStart(const nacl::NaClStartParams& params) { | |
235 struct NaClChromeMainArgs *args = NaClChromeMainArgsCreate(); | |
236 if (args == NULL) { | |
237 LOG(ERROR) << "NaClChromeMainArgsCreate() failed"; | |
238 return; | |
239 } | |
240 | |
241 if (params.enable_ipc_proxy) { | |
242 // Create the initial PPAPI IPC channel between the NaCl IRT and the | |
243 // browser process. The IRT uses this channel to communicate with the | |
244 // browser and to create additional IPC channels to renderer processes. | |
245 IPC::ChannelHandle handle = | |
246 IPC::Channel::GenerateVerifiedChannelID("nacl"); | |
247 scoped_refptr<NaClIPCAdapter> ipc_adapter( | |
248 new NaClIPCAdapter(handle, io_thread_.message_loop_proxy().get())); | |
249 ipc_adapter->ConnectChannel(); | |
250 | |
251 // Pass a NaClDesc to the untrusted side. This will hold a ref to the | |
252 // NaClIPCAdapter. | |
253 args->initial_ipc_desc = ipc_adapter->MakeNaClDesc(); | |
254 #if defined(OS_POSIX) | |
255 handle.socket = base::FileDescriptor( | |
256 ipc_adapter->TakeClientFileDescriptor(), true); | |
257 #endif | |
258 if (!Send(new NaClProcessHostMsg_PpapiChannelCreated(handle))) | |
259 LOG(ERROR) << "Failed to send IPC channel handle to NaClProcessHost."; | |
260 } | |
261 | |
262 std::vector<nacl::FileDescriptor> handles = params.handles; | |
263 | |
264 #if defined(OS_LINUX) || defined(OS_MACOSX) | |
265 args->urandom_fd = dup(base::GetUrandomFD()); | |
266 if (args->urandom_fd < 0) { | |
267 LOG(ERROR) << "Failed to dup() the urandom FD"; | |
268 return; | |
269 } | |
270 args->number_of_cores = number_of_cores_; | |
271 args->create_memory_object_func = CreateMemoryObject; | |
272 # if defined(OS_MACOSX) | |
273 CHECK(handles.size() >= 1); | |
274 g_shm_fd = nacl::ToNativeHandle(handles[handles.size() - 1]); | |
275 handles.pop_back(); | |
276 # endif | |
277 #endif | |
278 | |
279 if (params.uses_irt) { | |
280 CHECK(handles.size() >= 1); | |
281 NaClHandle irt_handle = nacl::ToNativeHandle(handles[handles.size() - 1]); | |
282 handles.pop_back(); | |
283 | |
284 #if defined(OS_WIN) | |
285 args->irt_fd = _open_osfhandle(reinterpret_cast<intptr_t>(irt_handle), | |
286 _O_RDONLY | _O_BINARY); | |
287 if (args->irt_fd < 0) { | |
288 LOG(ERROR) << "_open_osfhandle() failed"; | |
289 return; | |
290 } | |
291 #else | |
292 args->irt_fd = irt_handle; | |
293 #endif | |
294 } else { | |
295 // Otherwise, the IRT handle is not even sent. | |
296 args->irt_fd = -1; | |
297 } | |
298 | |
299 if (params.validation_cache_enabled) { | |
300 // SHA256 block size. | |
301 CHECK_EQ(params.validation_cache_key.length(), (size_t) 64); | |
302 // The cache structure is not freed and exists until the NaCl process exits. | |
303 args->validation_cache = CreateValidationCache( | |
304 new BrowserValidationDBProxy(this), params.validation_cache_key, | |
305 params.version); | |
306 } | |
307 | |
308 CHECK(handles.size() == 1); | |
309 args->imc_bootstrap_handle = nacl::ToNativeHandle(handles[0]); | |
310 args->enable_exception_handling = params.enable_exception_handling; | |
311 args->enable_debug_stub = params.enable_debug_stub; | |
312 args->enable_dyncode_syscalls = params.enable_dyncode_syscalls; | |
313 #if defined(OS_LINUX) || defined(OS_MACOSX) | |
314 args->debug_stub_server_bound_socket_fd = nacl::ToNativeHandle( | |
315 params.debug_stub_server_bound_socket); | |
316 #endif | |
317 #if defined(OS_WIN) | |
318 args->broker_duplicate_handle_func = BrokerDuplicateHandle; | |
319 args->attach_debug_exception_handler_func = AttachDebugExceptionHandler; | |
320 #endif | |
321 #if defined(OS_LINUX) | |
322 args->prereserved_sandbox_size = prereserved_sandbox_size_; | |
323 #endif | |
324 NaClChromeMainStart(args); | |
325 NOTREACHED(); | |
326 } | |
OLD | NEW |