1 // Copyright 2014 The Crashpad Authors. All rights reserved.
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14
15 #include <fcntl.h>
16 #include <getopt.h>
17 #include <libgen.h>
18 #include <stdio.h>
19 #include <string.h>
20 #include <sys/types.h>
21 #include <unistd.h>
22
23 #include <algorithm>
24 #include <string>
25 #include <vector>
26
27 #include "base/files/scoped_file.h"
28 #include "base/logging.h"
29 #include "base/mac/mach_logging.h"
30 #include "tools/tool_support.h"
31 #include "util/mach/bootstrap.h"
32 #include "util/mach/exc_server_variants.h"
33 #include "util/mach/exception_behaviors.h"
34 #include "util/mach/exception_types.h"
35 #include "util/mach/mach_extensions.h"
36 #include "util/mach/mach_message.h"
37 #include "util/mach/mach_message_server.h"
38 #include "util/mach/symbolic_constants_mach.h"
39 #include "util/posix/symbolic_constants_posix.h"
40 #include "util/stdlib/string_number_conversion.h"
41
42 namespace crashpad {
43 namespace {
44
45 struct Options {
46 std::string file_path;
47 std::string mach_service;
48 FILE* file;
49 int timeout_secs;
50 bool has_timeout;
51 MachMessageServer::Persistent persistent;
52 };
53
54 class ExceptionServer final : public UniversalMachExcServer::Interface {
55 public:
ExceptionServer(const Options & options,const std::string & me,int * exceptions_handled)56 ExceptionServer(const Options& options,
57 const std::string& me,
58 int* exceptions_handled)
59 : UniversalMachExcServer::Interface(),
60 options_(options),
61 me_(me),
62 exceptions_handled_(exceptions_handled) {}
63
64 // UniversalMachExcServer::Interface:
CatchMachException(exception_behavior_t behavior,exception_handler_t exception_port,thread_t thread,task_t task,exception_type_t exception,const mach_exception_data_type_t * code,mach_msg_type_number_t code_count,thread_state_flavor_t * flavor,ConstThreadState old_state,mach_msg_type_number_t old_state_count,thread_state_t new_state,mach_msg_type_number_t * new_state_count,const mach_msg_trailer_t * trailer,bool * destroy_complex_request)65 virtual kern_return_t CatchMachException(
66 exception_behavior_t behavior,
67 exception_handler_t exception_port,
68 thread_t thread,
69 task_t task,
70 exception_type_t exception,
71 const mach_exception_data_type_t* code,
72 mach_msg_type_number_t code_count,
73 thread_state_flavor_t* flavor,
74 ConstThreadState old_state,
75 mach_msg_type_number_t old_state_count,
76 thread_state_t new_state,
77 mach_msg_type_number_t* new_state_count,
78 const mach_msg_trailer_t* trailer,
79 bool* destroy_complex_request) override {
80 *destroy_complex_request = true;
81 ++*exceptions_handled_;
82
83 fprintf(options_.file,
84 "%s: behavior %s",
85 me_.c_str(),
86 ExceptionBehaviorToString(
87 behavior, kUseFullName | kUnknownIsNumeric | kUseOr).c_str());
88
89 kern_return_t kr;
90 if (ExceptionBehaviorHasIdentity(behavior)) {
91 // It’s not possible to call pid_for_task() once EXC_CORPSE_NOTIFY has
92 // been generated. It is possible to obtain the process ID by mapping the
93 // corpse kcdata area from the task’s address space at code[0] (size
94 // code[1]) and locating TASK_CRASHINFO_PID within that area. This area
95 // also includes TASK_CRASHINFO_CRASHED_THREADID which could be used
96 // instead of thread_info() below, and TASK_CRASHINFO_EXCEPTION_CODES
97 // which could be used to recover the exception codes passed to the
98 // EXC_CRASH handler. None of this is currently done because corpses are a
99 // new 10.11-only feature. See 10.11 <corpses/task_corpse.h> and
100 // <kern/kern_cdata.h>.
101 if (exception != EXC_CORPSE_NOTIFY) {
102 pid_t pid;
103 kr = pid_for_task(task, &pid);
104 if (kr != KERN_SUCCESS) {
105 fprintf(options_.file, "\n");
106 fflush(options_.file);
107 MACH_LOG(ERROR, kr) << "pid_for_task";
108 return KERN_FAILURE;
109 }
110 fprintf(options_.file, ", pid %d", pid);
111 }
112
113 thread_identifier_info identifier_info;
114 mach_msg_type_number_t count = THREAD_IDENTIFIER_INFO_COUNT;
115 kr = thread_info(thread,
116 THREAD_IDENTIFIER_INFO,
117 reinterpret_cast<thread_info_t>(&identifier_info),
118 &count);
119 if (kr != KERN_SUCCESS) {
120 fprintf(options_.file, "\n");
121 fflush(options_.file);
122 MACH_LOG(ERROR, kr) << "thread_info";
123 return KERN_FAILURE;
124 }
125 fprintf(options_.file, ", thread %lld", identifier_info.thread_id);
126 }
127
128 fprintf(
129 options_.file,
130 ", exception %s, codes[%d]",
131 ExceptionToString(exception, kUseFullName | kUnknownIsNumeric).c_str(),
132 code_count);
133
134 for (size_t index = 0; index < code_count; ++index) {
135 fprintf(options_.file,
136 "%s %#llx",
137 index != 0 ? "," : "",
138 code[index]);
139 }
140
141 if (exception == EXC_CRASH) {
142 mach_exception_code_t original_code_0;
143 int signal;
144 exception_type_t original_exception =
145 ExcCrashRecoverOriginalException(code[0], &original_code_0, &signal);
146 fprintf(options_.file,
147 ", original exception %s, original code[0] %lld, signal %s",
148 ExceptionToString(original_exception,
149 kUseFullName | kUnknownIsNumeric).c_str(),
150 original_code_0,
151 SignalToString(signal, kUseFullName | kUnknownIsNumeric).c_str());
152 }
153
154 if (ExceptionBehaviorHasState(behavior)) {
155 std::string flavor_string =
156 ThreadStateFlavorToString(*flavor, kUseFullName | kUnknownIsNumeric);
157 fprintf(options_.file,
158 ", flavor %s, old_state_count %d",
159 flavor_string.c_str(),
160 old_state_count);
161 }
162
163 fprintf(options_.file, "\n");
164 fflush(options_.file);
165
166 if (exception != EXC_CRASH && exception != kMachExceptionSimulated) {
167 // Find another handler.
168 return KERN_FAILURE;
169 }
170
171 ExcServerCopyState(
172 behavior, old_state, old_state_count, new_state, new_state_count);
173
174 return ExcServerSuccessfulReturnValue(exception, behavior, false);
175 }
176
177 private:
178 const Options& options_;
179 const std::string& me_;
180 int* exceptions_handled_;
181 };
182
Usage(const std::string & me)183 void Usage(const std::string& me) {
184 fprintf(stderr,
185 "Usage: %s -m SERVICE [OPTION]...\n"
186 "Catch Mach exceptions and display information about them.\n"
187 "\n"
188 " -f, --file=FILE append information to FILE instead of stdout\n"
189 " -m, --mach-service=SERVICE register SERVICE with the bootstrap server\n"
190 " -p, --persistent continue processing exceptions after the first\n"
191 " -t, --timeout=TIMEOUT run for a maximum of TIMEOUT seconds\n"
192 " --help display this help and exit\n"
193 " --version output version information and exit\n",
194 me.c_str());
195 ToolSupport::UsageTail(me);
196 }
197
CatchExceptionToolMain(int argc,char * argv[])198 int CatchExceptionToolMain(int argc, char* argv[]) {
199 const std::string me(basename(argv[0]));
200
201 enum OptionFlags {
202 // “Short” (single-character) options.
203 kOptionFile = 'f',
204 kOptionMachService = 'm',
205 kOptionPersistent = 'p',
206 kOptionTimeout = 't',
207
208 // Long options without short equivalents.
209 kOptionLastChar = 255,
210
211 // Standard options.
212 kOptionHelp = -2,
213 kOptionVersion = -3,
214 };
215
216 Options options = {};
217
218 static constexpr option long_options[] = {
219 {"file", required_argument, nullptr, kOptionFile},
220 {"mach-service", required_argument, nullptr, kOptionMachService},
221 {"persistent", no_argument, nullptr, kOptionPersistent},
222 {"timeout", required_argument, nullptr, kOptionTimeout},
223 {"help", no_argument, nullptr, kOptionHelp},
224 {"version", no_argument, nullptr, kOptionVersion},
225 {nullptr, 0, nullptr, 0},
226 };
227
228 int opt;
229 while ((opt = getopt_long(argc, argv, "f:m:pt:", long_options, nullptr)) !=
230 -1) {
231 switch (opt) {
232 case kOptionFile:
233 options.file_path = optarg;
234 break;
235 case kOptionMachService:
236 options.mach_service = optarg;
237 break;
238 case kOptionPersistent:
239 options.persistent = MachMessageServer::kPersistent;
240 break;
241 case kOptionTimeout:
242 if (!StringToNumber(optarg, &options.timeout_secs) ||
243 options.timeout_secs < 0) {
244 ToolSupport::UsageHint(me, "-t requires a zero or positive TIMEOUT");
245 return EXIT_FAILURE;
246 }
247 options.has_timeout = true;
248 break;
249 case kOptionHelp:
250 Usage(me);
251 return EXIT_SUCCESS;
252 case kOptionVersion:
253 ToolSupport::Version(me);
254 return EXIT_SUCCESS;
255 default:
256 ToolSupport::UsageHint(me, nullptr);
257 return EXIT_FAILURE;
258 }
259 }
260 argc -= optind;
261 argv += optind;
262
263 if (options.mach_service.empty()) {
264 ToolSupport::UsageHint(me, "-m is required");
265 return EXIT_FAILURE;
266 }
267
268 base::mac::ScopedMachReceiveRight
269 service_port(BootstrapCheckIn(options.mach_service));
270 if (service_port == kMachPortNull) {
271 return EXIT_FAILURE;
272 }
273
274 base::ScopedFILE file_owner;
275 if (options.file_path.empty()) {
276 options.file = stdout;
277 } else {
278 file_owner.reset(fopen(options.file_path.c_str(), "a"));
279 if (!file_owner.get()) {
280 PLOG(ERROR) << "fopen " << options.file_path;
281 return EXIT_FAILURE;
282 }
283 options.file = file_owner.get();
284 if (fcntl(fileno(options.file), F_SETFD, FD_CLOEXEC) == -1) {
285 PLOG(ERROR) << "fcntl " << options.file_path;
286 return EXIT_FAILURE;
287 }
288 }
289
290 int exceptions_handled = 0;
291 ExceptionServer exception_server(options, me, &exceptions_handled);
292 UniversalMachExcServer universal_mach_exc_server(&exception_server);
293
294 // Assume that if persistent mode has been requested, it’s desirable to ignore
295 // large messages and keep running.
296 MachMessageServer::ReceiveLarge receive_large =
297 (options.persistent == MachMessageServer::kPersistent)
298 ? MachMessageServer::kReceiveLargeIgnore
299 : MachMessageServer::kReceiveLargeError;
300
301 mach_msg_timeout_t timeout_ms;
302 if (!options.has_timeout) {
303 timeout_ms = kMachMessageTimeoutWaitIndefinitely;
304 } else if (options.timeout_secs == 0) {
305 timeout_ms = kMachMessageTimeoutNonblocking;
306 } else {
307 timeout_ms = options.timeout_secs * 1000;
308 }
309
310 mach_msg_return_t mr = MachMessageServer::Run(&universal_mach_exc_server,
311 service_port.get(),
312 MACH_MSG_OPTION_NONE,
313 options.persistent,
314 receive_large,
315 timeout_ms);
316 if (mr == MACH_RCV_TIMED_OUT && options.has_timeout && options.persistent &&
317 exceptions_handled) {
318 // This is not an error: when exiting on timeout during persistent
319 // processing and at least one exception was handled, it’s considered a
320 // success.
321 } else if (mr != MACH_MSG_SUCCESS) {
322 MACH_LOG(ERROR, mr) << "MachMessageServer::Run";
323 return EXIT_FAILURE;
324 }
325
326 return EXIT_SUCCESS;
327 }
328
329 } // namespace
330 } // namespace crashpad
331
main(int argc,char * argv[])332 int main(int argc, char* argv[]) {
333 return crashpad::CatchExceptionToolMain(argc, argv);
334 }
335