1 /*
2  * Copyright (C) 2005 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "Parcel"
18 //#define LOG_NDEBUG 0
19 
20 #include <binder/Parcel.h>
21 
22 #include <binder/IPCThreadState.h>
23 #include <binder/Binder.h>
24 #include <binder/BpBinder.h>
25 #include <binder/ProcessState.h>
26 #include <binder/TextOutput.h>
27 
28 #include <errno.h>
29 #include <utils/Debug.h>
30 #include <utils/Log.h>
31 #include <utils/String8.h>
32 #include <utils/String16.h>
33 #include <utils/misc.h>
34 #include <utils/Flattenable.h>
35 #include <cutils/ashmem.h>
36 
37 #include <private/binder/binder_module.h>
38 #include <private/binder/Static.h>
39 
40 #include <inttypes.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <stdint.h>
44 #include <sys/mman.h>
45 
46 #ifndef INT32_MAX
47 #define INT32_MAX ((int32_t)(2147483647))
48 #endif
49 
50 #define LOG_REFS(...)
51 //#define LOG_REFS(...) ALOG(LOG_DEBUG, "Parcel", __VA_ARGS__)
52 #define LOG_ALLOC(...)
53 //#define LOG_ALLOC(...) ALOG(LOG_DEBUG, "Parcel", __VA_ARGS__)
54 
55 // ---------------------------------------------------------------------------
56 
57 // This macro should never be used at runtime, as a too large value
58 // of s could cause an integer overflow. Instead, you should always
59 // use the wrapper function pad_size()
60 #define PAD_SIZE_UNSAFE(s) (((s)+3)&~3)
61 
pad_size(size_t s)62 static size_t pad_size(size_t s) {
63     if (s > (SIZE_T_MAX - 3)) {
64         abort();
65     }
66     return PAD_SIZE_UNSAFE(s);
67 }
68 
69 // Note: must be kept in sync with android/os/StrictMode.java's PENALTY_GATHER
70 #define STRICT_MODE_PENALTY_GATHER (0x40 << 16)
71 
72 // Note: must be kept in sync with android/os/Parcel.java's EX_HAS_REPLY_HEADER
73 #define EX_HAS_REPLY_HEADER -128
74 
75 // XXX This can be made public if we want to provide
76 // support for typed data.
77 struct small_flat_data
78 {
79     uint32_t type;
80     uint32_t data;
81 };
82 
83 namespace android {
84 
85 static pthread_mutex_t gParcelGlobalAllocSizeLock = PTHREAD_MUTEX_INITIALIZER;
86 static size_t gParcelGlobalAllocSize = 0;
87 static size_t gParcelGlobalAllocCount = 0;
88 
89 // Maximum size of a blob to transfer in-place.
90 static const size_t BLOB_INPLACE_LIMIT = 16 * 1024;
91 
92 enum {
93     BLOB_INPLACE = 0,
94     BLOB_ASHMEM_IMMUTABLE = 1,
95     BLOB_ASHMEM_MUTABLE = 2,
96 };
97 
acquire_object(const sp<ProcessState> & proc,const flat_binder_object & obj,const void * who)98 void acquire_object(const sp<ProcessState>& proc,
99     const flat_binder_object& obj, const void* who)
100 {
101     switch (obj.type) {
102         case BINDER_TYPE_BINDER:
103             if (obj.binder) {
104                 LOG_REFS("Parcel %p acquiring reference on local %p", who, obj.cookie);
105                 reinterpret_cast<IBinder*>(obj.cookie)->incStrong(who);
106             }
107             return;
108         case BINDER_TYPE_WEAK_BINDER:
109             if (obj.binder)
110                 reinterpret_cast<RefBase::weakref_type*>(obj.binder)->incWeak(who);
111             return;
112         case BINDER_TYPE_HANDLE: {
113             const sp<IBinder> b = proc->getStrongProxyForHandle(obj.handle);
114             if (b != NULL) {
115                 LOG_REFS("Parcel %p acquiring reference on remote %p", who, b.get());
116                 b->incStrong(who);
117             }
118             return;
119         }
120         case BINDER_TYPE_WEAK_HANDLE: {
121             const wp<IBinder> b = proc->getWeakProxyForHandle(obj.handle);
122             if (b != NULL) b.get_refs()->incWeak(who);
123             return;
124         }
125         case BINDER_TYPE_FD: {
126             // intentionally blank -- nothing to do to acquire this, but we do
127             // recognize it as a legitimate object type.
128             return;
129         }
130     }
131 
132     ALOGD("Invalid object type 0x%08x", obj.type);
133 }
134 
release_object(const sp<ProcessState> & proc,const flat_binder_object & obj,const void * who)135 void release_object(const sp<ProcessState>& proc,
136     const flat_binder_object& obj, const void* who)
137 {
138     switch (obj.type) {
139         case BINDER_TYPE_BINDER:
140             if (obj.binder) {
141                 LOG_REFS("Parcel %p releasing reference on local %p", who, obj.cookie);
142                 reinterpret_cast<IBinder*>(obj.cookie)->decStrong(who);
143             }
144             return;
145         case BINDER_TYPE_WEAK_BINDER:
146             if (obj.binder)
147                 reinterpret_cast<RefBase::weakref_type*>(obj.binder)->decWeak(who);
148             return;
149         case BINDER_TYPE_HANDLE: {
150             const sp<IBinder> b = proc->getStrongProxyForHandle(obj.handle);
151             if (b != NULL) {
152                 LOG_REFS("Parcel %p releasing reference on remote %p", who, b.get());
153                 b->decStrong(who);
154             }
155             return;
156         }
157         case BINDER_TYPE_WEAK_HANDLE: {
158             const wp<IBinder> b = proc->getWeakProxyForHandle(obj.handle);
159             if (b != NULL) b.get_refs()->decWeak(who);
160             return;
161         }
162         case BINDER_TYPE_FD: {
163             if (obj.cookie != 0) close(obj.handle);
164             return;
165         }
166     }
167 
168     ALOGE("Invalid object type 0x%08x", obj.type);
169 }
170 
finish_flatten_binder(const sp<IBinder> &,const flat_binder_object & flat,Parcel * out)171 inline static status_t finish_flatten_binder(
172     const sp<IBinder>& /*binder*/, const flat_binder_object& flat, Parcel* out)
173 {
174     return out->writeObject(flat, false);
175 }
176 
flatten_binder(const sp<ProcessState> &,const sp<IBinder> & binder,Parcel * out)177 status_t flatten_binder(const sp<ProcessState>& /*proc*/,
178     const sp<IBinder>& binder, Parcel* out)
179 {
180     flat_binder_object obj;
181 
182     obj.flags = 0x7f | FLAT_BINDER_FLAG_ACCEPTS_FDS;
183     if (binder != NULL) {
184         IBinder *local = binder->localBinder();
185         if (!local) {
186             BpBinder *proxy = binder->remoteBinder();
187             if (proxy == NULL) {
188                 ALOGE("null proxy");
189             }
190             const int32_t handle = proxy ? proxy->handle() : 0;
191             obj.type = BINDER_TYPE_HANDLE;
192             obj.binder = 0; /* Don't pass uninitialized stack data to a remote process */
193             obj.handle = handle;
194             obj.cookie = 0;
195         } else {
196             obj.type = BINDER_TYPE_BINDER;
197             obj.binder = reinterpret_cast<uintptr_t>(local->getWeakRefs());
198             obj.cookie = reinterpret_cast<uintptr_t>(local);
199         }
200     } else {
201         obj.type = BINDER_TYPE_BINDER;
202         obj.binder = 0;
203         obj.cookie = 0;
204     }
205 
206     return finish_flatten_binder(binder, obj, out);
207 }
208 
flatten_binder(const sp<ProcessState> &,const wp<IBinder> & binder,Parcel * out)209 status_t flatten_binder(const sp<ProcessState>& /*proc*/,
210     const wp<IBinder>& binder, Parcel* out)
211 {
212     flat_binder_object obj;
213 
214     obj.flags = 0x7f | FLAT_BINDER_FLAG_ACCEPTS_FDS;
215     if (binder != NULL) {
216         sp<IBinder> real = binder.promote();
217         if (real != NULL) {
218             IBinder *local = real->localBinder();
219             if (!local) {
220                 BpBinder *proxy = real->remoteBinder();
221                 if (proxy == NULL) {
222                     ALOGE("null proxy");
223                 }
224                 const int32_t handle = proxy ? proxy->handle() : 0;
225                 obj.type = BINDER_TYPE_WEAK_HANDLE;
226                 obj.binder = 0; /* Don't pass uninitialized stack data to a remote process */
227                 obj.handle = handle;
228                 obj.cookie = 0;
229             } else {
230                 obj.type = BINDER_TYPE_WEAK_BINDER;
231                 obj.binder = reinterpret_cast<uintptr_t>(binder.get_refs());
232                 obj.cookie = reinterpret_cast<uintptr_t>(binder.unsafe_get());
233             }
234             return finish_flatten_binder(real, obj, out);
235         }
236 
237         // XXX How to deal?  In order to flatten the given binder,
238         // we need to probe it for information, which requires a primary
239         // reference...  but we don't have one.
240         //
241         // The OpenBinder implementation uses a dynamic_cast<> here,
242         // but we can't do that with the different reference counting
243         // implementation we are using.
244         ALOGE("Unable to unflatten Binder weak reference!");
245         obj.type = BINDER_TYPE_BINDER;
246         obj.binder = 0;
247         obj.cookie = 0;
248         return finish_flatten_binder(NULL, obj, out);
249 
250     } else {
251         obj.type = BINDER_TYPE_BINDER;
252         obj.binder = 0;
253         obj.cookie = 0;
254         return finish_flatten_binder(NULL, obj, out);
255     }
256 }
257 
finish_unflatten_binder(BpBinder *,const flat_binder_object &,const Parcel &)258 inline static status_t finish_unflatten_binder(
259     BpBinder* /*proxy*/, const flat_binder_object& /*flat*/,
260     const Parcel& /*in*/)
261 {
262     return NO_ERROR;
263 }
264 
unflatten_binder(const sp<ProcessState> & proc,const Parcel & in,sp<IBinder> * out)265 status_t unflatten_binder(const sp<ProcessState>& proc,
266     const Parcel& in, sp<IBinder>* out)
267 {
268     const flat_binder_object* flat = in.readObject(false);
269 
270     if (flat) {
271         switch (flat->type) {
272             case BINDER_TYPE_BINDER:
273                 *out = reinterpret_cast<IBinder*>(flat->cookie);
274                 return finish_unflatten_binder(NULL, *flat, in);
275             case BINDER_TYPE_HANDLE:
276                 *out = proc->getStrongProxyForHandle(flat->handle);
277                 return finish_unflatten_binder(
278                     static_cast<BpBinder*>(out->get()), *flat, in);
279         }
280     }
281     return BAD_TYPE;
282 }
283 
unflatten_binder(const sp<ProcessState> & proc,const Parcel & in,wp<IBinder> * out)284 status_t unflatten_binder(const sp<ProcessState>& proc,
285     const Parcel& in, wp<IBinder>* out)
286 {
287     const flat_binder_object* flat = in.readObject(false);
288 
289     if (flat) {
290         switch (flat->type) {
291             case BINDER_TYPE_BINDER:
292                 *out = reinterpret_cast<IBinder*>(flat->cookie);
293                 return finish_unflatten_binder(NULL, *flat, in);
294             case BINDER_TYPE_WEAK_BINDER:
295                 if (flat->binder != 0) {
296                     out->set_object_and_refs(
297                         reinterpret_cast<IBinder*>(flat->cookie),
298                         reinterpret_cast<RefBase::weakref_type*>(flat->binder));
299                 } else {
300                     *out = NULL;
301                 }
302                 return finish_unflatten_binder(NULL, *flat, in);
303             case BINDER_TYPE_HANDLE:
304             case BINDER_TYPE_WEAK_HANDLE:
305                 *out = proc->getWeakProxyForHandle(flat->handle);
306                 return finish_unflatten_binder(
307                     static_cast<BpBinder*>(out->unsafe_get()), *flat, in);
308         }
309     }
310     return BAD_TYPE;
311 }
312 
313 // ---------------------------------------------------------------------------
314 
Parcel()315 Parcel::Parcel()
316 {
317     LOG_ALLOC("Parcel %p: constructing", this);
318     initState();
319 }
320 
~Parcel()321 Parcel::~Parcel()
322 {
323     freeDataNoInit();
324     LOG_ALLOC("Parcel %p: destroyed", this);
325 }
326 
getGlobalAllocSize()327 size_t Parcel::getGlobalAllocSize() {
328     pthread_mutex_lock(&gParcelGlobalAllocSizeLock);
329     size_t size = gParcelGlobalAllocSize;
330     pthread_mutex_unlock(&gParcelGlobalAllocSizeLock);
331     return size;
332 }
333 
getGlobalAllocCount()334 size_t Parcel::getGlobalAllocCount() {
335     pthread_mutex_lock(&gParcelGlobalAllocSizeLock);
336     size_t count = gParcelGlobalAllocCount;
337     pthread_mutex_unlock(&gParcelGlobalAllocSizeLock);
338     return count;
339 }
340 
data() const341 const uint8_t* Parcel::data() const
342 {
343     return mData;
344 }
345 
dataSize() const346 size_t Parcel::dataSize() const
347 {
348     return (mDataSize > mDataPos ? mDataSize : mDataPos);
349 }
350 
dataAvail() const351 size_t Parcel::dataAvail() const
352 {
353     // TODO: decide what to do about the possibility that this can
354     // report an available-data size that exceeds a Java int's max
355     // positive value, causing havoc.  Fortunately this will only
356     // happen if someone constructs a Parcel containing more than two
357     // gigabytes of data, which on typical phone hardware is simply
358     // not possible.
359     return dataSize() - dataPosition();
360 }
361 
dataPosition() const362 size_t Parcel::dataPosition() const
363 {
364     return mDataPos;
365 }
366 
dataCapacity() const367 size_t Parcel::dataCapacity() const
368 {
369     return mDataCapacity;
370 }
371 
setDataSize(size_t size)372 status_t Parcel::setDataSize(size_t size)
373 {
374     if (size > INT32_MAX) {
375         // don't accept size_t values which may have come from an
376         // inadvertent conversion from a negative int.
377         return BAD_VALUE;
378     }
379 
380     status_t err;
381     err = continueWrite(size);
382     if (err == NO_ERROR) {
383         mDataSize = size;
384         ALOGV("setDataSize Setting data size of %p to %zu", this, mDataSize);
385     }
386     return err;
387 }
388 
setDataPosition(size_t pos) const389 void Parcel::setDataPosition(size_t pos) const
390 {
391     if (pos > INT32_MAX) {
392         // don't accept size_t values which may have come from an
393         // inadvertent conversion from a negative int.
394         abort();
395     }
396 
397     mDataPos = pos;
398     mNextObjectHint = 0;
399 }
400 
setDataCapacity(size_t size)401 status_t Parcel::setDataCapacity(size_t size)
402 {
403     if (size > INT32_MAX) {
404         // don't accept size_t values which may have come from an
405         // inadvertent conversion from a negative int.
406         return BAD_VALUE;
407     }
408 
409     if (size > mDataCapacity) return continueWrite(size);
410     return NO_ERROR;
411 }
412 
setData(const uint8_t * buffer,size_t len)413 status_t Parcel::setData(const uint8_t* buffer, size_t len)
414 {
415     if (len > INT32_MAX) {
416         // don't accept size_t values which may have come from an
417         // inadvertent conversion from a negative int.
418         return BAD_VALUE;
419     }
420 
421     status_t err = restartWrite(len);
422     if (err == NO_ERROR) {
423         memcpy(const_cast<uint8_t*>(data()), buffer, len);
424         mDataSize = len;
425         mFdsKnown = false;
426     }
427     return err;
428 }
429 
appendFrom(const Parcel * parcel,size_t offset,size_t len)430 status_t Parcel::appendFrom(const Parcel *parcel, size_t offset, size_t len)
431 {
432     const sp<ProcessState> proc(ProcessState::self());
433     status_t err;
434     const uint8_t *data = parcel->mData;
435     const binder_size_t *objects = parcel->mObjects;
436     size_t size = parcel->mObjectsSize;
437     int startPos = mDataPos;
438     int firstIndex = -1, lastIndex = -2;
439 
440     if (len == 0) {
441         return NO_ERROR;
442     }
443 
444     if (len > INT32_MAX) {
445         // don't accept size_t values which may have come from an
446         // inadvertent conversion from a negative int.
447         return BAD_VALUE;
448     }
449 
450     // range checks against the source parcel size
451     if ((offset > parcel->mDataSize)
452             || (len > parcel->mDataSize)
453             || (offset + len > parcel->mDataSize)) {
454         return BAD_VALUE;
455     }
456 
457     // Count objects in range
458     for (int i = 0; i < (int) size; i++) {
459         size_t off = objects[i];
460         if ((off >= offset) && (off + sizeof(flat_binder_object) <= offset + len)) {
461             if (firstIndex == -1) {
462                 firstIndex = i;
463             }
464             lastIndex = i;
465         }
466     }
467     int numObjects = lastIndex - firstIndex + 1;
468 
469     if ((mDataSize+len) > mDataCapacity) {
470         // grow data
471         err = growData(len);
472         if (err != NO_ERROR) {
473             return err;
474         }
475     }
476 
477     // append data
478     memcpy(mData + mDataPos, data + offset, len);
479     mDataPos += len;
480     mDataSize += len;
481 
482     err = NO_ERROR;
483 
484     if (numObjects > 0) {
485         // grow objects
486         if (mObjectsCapacity < mObjectsSize + numObjects) {
487             size_t newSize = ((mObjectsSize + numObjects)*3)/2;
488             if (newSize < mObjectsSize) return NO_MEMORY;   // overflow
489             binder_size_t *objects =
490                 (binder_size_t*)realloc(mObjects, newSize*sizeof(binder_size_t));
491             if (objects == (binder_size_t*)0) {
492                 return NO_MEMORY;
493             }
494             mObjects = objects;
495             mObjectsCapacity = newSize;
496         }
497 
498         // append and acquire objects
499         int idx = mObjectsSize;
500         for (int i = firstIndex; i <= lastIndex; i++) {
501             size_t off = objects[i] - offset + startPos;
502             mObjects[idx++] = off;
503             mObjectsSize++;
504 
505             flat_binder_object* flat
506                 = reinterpret_cast<flat_binder_object*>(mData + off);
507             acquire_object(proc, *flat, this);
508 
509             if (flat->type == BINDER_TYPE_FD) {
510                 // If this is a file descriptor, we need to dup it so the
511                 // new Parcel now owns its own fd, and can declare that we
512                 // officially know we have fds.
513                 flat->handle = dup(flat->handle);
514                 flat->cookie = 1;
515                 mHasFds = mFdsKnown = true;
516                 if (!mAllowFds) {
517                     err = FDS_NOT_ALLOWED;
518                 }
519             }
520         }
521     }
522 
523     return err;
524 }
525 
allowFds() const526 bool Parcel::allowFds() const
527 {
528     return mAllowFds;
529 }
530 
pushAllowFds(bool allowFds)531 bool Parcel::pushAllowFds(bool allowFds)
532 {
533     const bool origValue = mAllowFds;
534     if (!allowFds) {
535         mAllowFds = false;
536     }
537     return origValue;
538 }
539 
restoreAllowFds(bool lastValue)540 void Parcel::restoreAllowFds(bool lastValue)
541 {
542     mAllowFds = lastValue;
543 }
544 
hasFileDescriptors() const545 bool Parcel::hasFileDescriptors() const
546 {
547     if (!mFdsKnown) {
548         scanForFds();
549     }
550     return mHasFds;
551 }
552 
553 // Write RPC headers.  (previously just the interface token)
writeInterfaceToken(const String16 & interface)554 status_t Parcel::writeInterfaceToken(const String16& interface)
555 {
556     writeInt32(IPCThreadState::self()->getStrictModePolicy() |
557                STRICT_MODE_PENALTY_GATHER);
558     // currently the interface identification token is just its name as a string
559     return writeString16(interface);
560 }
561 
checkInterface(IBinder * binder) const562 bool Parcel::checkInterface(IBinder* binder) const
563 {
564     return enforceInterface(binder->getInterfaceDescriptor());
565 }
566 
enforceInterface(const String16 & interface,IPCThreadState * threadState) const567 bool Parcel::enforceInterface(const String16& interface,
568                               IPCThreadState* threadState) const
569 {
570     int32_t strictPolicy = readInt32();
571     if (threadState == NULL) {
572         threadState = IPCThreadState::self();
573     }
574     if ((threadState->getLastTransactionBinderFlags() &
575          IBinder::FLAG_ONEWAY) != 0) {
576       // For one-way calls, the callee is running entirely
577       // disconnected from the caller, so disable StrictMode entirely.
578       // Not only does disk/network usage not impact the caller, but
579       // there's no way to commuicate back any violations anyway.
580       threadState->setStrictModePolicy(0);
581     } else {
582       threadState->setStrictModePolicy(strictPolicy);
583     }
584     const String16 str(readString16());
585     if (str == interface) {
586         return true;
587     } else {
588         ALOGW("**** enforceInterface() expected '%s' but read '%s'",
589                 String8(interface).string(), String8(str).string());
590         return false;
591     }
592 }
593 
objects() const594 const binder_size_t* Parcel::objects() const
595 {
596     return mObjects;
597 }
598 
objectsCount() const599 size_t Parcel::objectsCount() const
600 {
601     return mObjectsSize;
602 }
603 
errorCheck() const604 status_t Parcel::errorCheck() const
605 {
606     return mError;
607 }
608 
setError(status_t err)609 void Parcel::setError(status_t err)
610 {
611     mError = err;
612 }
613 
finishWrite(size_t len)614 status_t Parcel::finishWrite(size_t len)
615 {
616     if (len > INT32_MAX) {
617         // don't accept size_t values which may have come from an
618         // inadvertent conversion from a negative int.
619         return BAD_VALUE;
620     }
621 
622     //printf("Finish write of %d\n", len);
623     mDataPos += len;
624     ALOGV("finishWrite Setting data pos of %p to %zu", this, mDataPos);
625     if (mDataPos > mDataSize) {
626         mDataSize = mDataPos;
627         ALOGV("finishWrite Setting data size of %p to %zu", this, mDataSize);
628     }
629     //printf("New pos=%d, size=%d\n", mDataPos, mDataSize);
630     return NO_ERROR;
631 }
632 
writeUnpadded(const void * data,size_t len)633 status_t Parcel::writeUnpadded(const void* data, size_t len)
634 {
635     if (len > INT32_MAX) {
636         // don't accept size_t values which may have come from an
637         // inadvertent conversion from a negative int.
638         return BAD_VALUE;
639     }
640 
641     size_t end = mDataPos + len;
642     if (end < mDataPos) {
643         // integer overflow
644         return BAD_VALUE;
645     }
646 
647     if (end <= mDataCapacity) {
648 restart_write:
649         memcpy(mData+mDataPos, data, len);
650         return finishWrite(len);
651     }
652 
653     status_t err = growData(len);
654     if (err == NO_ERROR) goto restart_write;
655     return err;
656 }
657 
write(const void * data,size_t len)658 status_t Parcel::write(const void* data, size_t len)
659 {
660     if (len > INT32_MAX) {
661         // don't accept size_t values which may have come from an
662         // inadvertent conversion from a negative int.
663         return BAD_VALUE;
664     }
665 
666     void* const d = writeInplace(len);
667     if (d) {
668         memcpy(d, data, len);
669         return NO_ERROR;
670     }
671     return mError;
672 }
673 
writeInplace(size_t len)674 void* Parcel::writeInplace(size_t len)
675 {
676     if (len > INT32_MAX) {
677         // don't accept size_t values which may have come from an
678         // inadvertent conversion from a negative int.
679         return NULL;
680     }
681 
682     const size_t padded = pad_size(len);
683 
684     // sanity check for integer overflow
685     if (mDataPos+padded < mDataPos) {
686         return NULL;
687     }
688 
689     if ((mDataPos+padded) <= mDataCapacity) {
690 restart_write:
691         //printf("Writing %ld bytes, padded to %ld\n", len, padded);
692         uint8_t* const data = mData+mDataPos;
693 
694         // Need to pad at end?
695         if (padded != len) {
696 #if BYTE_ORDER == BIG_ENDIAN
697             static const uint32_t mask[4] = {
698                 0x00000000, 0xffffff00, 0xffff0000, 0xff000000
699             };
700 #endif
701 #if BYTE_ORDER == LITTLE_ENDIAN
702             static const uint32_t mask[4] = {
703                 0x00000000, 0x00ffffff, 0x0000ffff, 0x000000ff
704             };
705 #endif
706             //printf("Applying pad mask: %p to %p\n", (void*)mask[padded-len],
707             //    *reinterpret_cast<void**>(data+padded-4));
708             *reinterpret_cast<uint32_t*>(data+padded-4) &= mask[padded-len];
709         }
710 
711         finishWrite(padded);
712         return data;
713     }
714 
715     status_t err = growData(padded);
716     if (err == NO_ERROR) goto restart_write;
717     return NULL;
718 }
719 
writeInt32(int32_t val)720 status_t Parcel::writeInt32(int32_t val)
721 {
722     return writeAligned(val);
723 }
724 
writeUint32(uint32_t val)725 status_t Parcel::writeUint32(uint32_t val)
726 {
727     return writeAligned(val);
728 }
729 
writeInt32Array(size_t len,const int32_t * val)730 status_t Parcel::writeInt32Array(size_t len, const int32_t *val) {
731     if (len > INT32_MAX) {
732         // don't accept size_t values which may have come from an
733         // inadvertent conversion from a negative int.
734         return BAD_VALUE;
735     }
736 
737     if (!val) {
738         return writeInt32(-1);
739     }
740     status_t ret = writeInt32(static_cast<uint32_t>(len));
741     if (ret == NO_ERROR) {
742         ret = write(val, len * sizeof(*val));
743     }
744     return ret;
745 }
writeByteArray(size_t len,const uint8_t * val)746 status_t Parcel::writeByteArray(size_t len, const uint8_t *val) {
747     if (len > INT32_MAX) {
748         // don't accept size_t values which may have come from an
749         // inadvertent conversion from a negative int.
750         return BAD_VALUE;
751     }
752 
753     if (!val) {
754         return writeInt32(-1);
755     }
756     status_t ret = writeInt32(static_cast<uint32_t>(len));
757     if (ret == NO_ERROR) {
758         ret = write(val, len * sizeof(*val));
759     }
760     return ret;
761 }
762 
writeInt64(int64_t val)763 status_t Parcel::writeInt64(int64_t val)
764 {
765     return writeAligned(val);
766 }
767 
writeUint64(uint64_t val)768 status_t Parcel::writeUint64(uint64_t val)
769 {
770     return writeAligned(val);
771 }
772 
writePointer(uintptr_t val)773 status_t Parcel::writePointer(uintptr_t val)
774 {
775     return writeAligned<binder_uintptr_t>(val);
776 }
777 
writeFloat(float val)778 status_t Parcel::writeFloat(float val)
779 {
780     return writeAligned(val);
781 }
782 
783 #if defined(__mips__) && defined(__mips_hard_float)
784 
writeDouble(double val)785 status_t Parcel::writeDouble(double val)
786 {
787     union {
788         double d;
789         unsigned long long ll;
790     } u;
791     u.d = val;
792     return writeAligned(u.ll);
793 }
794 
795 #else
796 
writeDouble(double val)797 status_t Parcel::writeDouble(double val)
798 {
799     return writeAligned(val);
800 }
801 
802 #endif
803 
writeCString(const char * str)804 status_t Parcel::writeCString(const char* str)
805 {
806     return write(str, strlen(str)+1);
807 }
808 
writeString8(const String8 & str)809 status_t Parcel::writeString8(const String8& str)
810 {
811     status_t err = writeInt32(str.bytes());
812     // only write string if its length is more than zero characters,
813     // as readString8 will only read if the length field is non-zero.
814     // this is slightly different from how writeString16 works.
815     if (str.bytes() > 0 && err == NO_ERROR) {
816         err = write(str.string(), str.bytes()+1);
817     }
818     return err;
819 }
820 
writeString16(const String16 & str)821 status_t Parcel::writeString16(const String16& str)
822 {
823     return writeString16(str.string(), str.size());
824 }
825 
writeString16(const char16_t * str,size_t len)826 status_t Parcel::writeString16(const char16_t* str, size_t len)
827 {
828     if (str == NULL) return writeInt32(-1);
829 
830     status_t err = writeInt32(len);
831     if (err == NO_ERROR) {
832         len *= sizeof(char16_t);
833         uint8_t* data = (uint8_t*)writeInplace(len+sizeof(char16_t));
834         if (data) {
835             memcpy(data, str, len);
836             *reinterpret_cast<char16_t*>(data+len) = 0;
837             return NO_ERROR;
838         }
839         err = mError;
840     }
841     return err;
842 }
843 
writeStrongBinder(const sp<IBinder> & val)844 status_t Parcel::writeStrongBinder(const sp<IBinder>& val)
845 {
846     return flatten_binder(ProcessState::self(), val, this);
847 }
848 
writeWeakBinder(const wp<IBinder> & val)849 status_t Parcel::writeWeakBinder(const wp<IBinder>& val)
850 {
851     return flatten_binder(ProcessState::self(), val, this);
852 }
853 
writeNativeHandle(const native_handle * handle)854 status_t Parcel::writeNativeHandle(const native_handle* handle)
855 {
856     if (!handle || handle->version != sizeof(native_handle))
857         return BAD_TYPE;
858 
859     status_t err;
860     err = writeInt32(handle->numFds);
861     if (err != NO_ERROR) return err;
862 
863     err = writeInt32(handle->numInts);
864     if (err != NO_ERROR) return err;
865 
866     for (int i=0 ; err==NO_ERROR && i<handle->numFds ; i++)
867         err = writeDupFileDescriptor(handle->data[i]);
868 
869     if (err != NO_ERROR) {
870         ALOGD("write native handle, write dup fd failed");
871         return err;
872     }
873     err = write(handle->data + handle->numFds, sizeof(int)*handle->numInts);
874     return err;
875 }
876 
writeFileDescriptor(int fd,bool takeOwnership)877 status_t Parcel::writeFileDescriptor(int fd, bool takeOwnership)
878 {
879     flat_binder_object obj;
880     obj.type = BINDER_TYPE_FD;
881     obj.flags = 0x7f | FLAT_BINDER_FLAG_ACCEPTS_FDS;
882     obj.binder = 0; /* Don't pass uninitialized stack data to a remote process */
883     obj.handle = fd;
884     obj.cookie = takeOwnership ? 1 : 0;
885     return writeObject(obj, true);
886 }
887 
writeDupFileDescriptor(int fd)888 status_t Parcel::writeDupFileDescriptor(int fd)
889 {
890     int dupFd = dup(fd);
891     if (dupFd < 0) {
892         return -errno;
893     }
894     status_t err = writeFileDescriptor(dupFd, true /*takeOwnership*/);
895     if (err) {
896         close(dupFd);
897     }
898     return err;
899 }
900 
writeBlob(size_t len,bool mutableCopy,WritableBlob * outBlob)901 status_t Parcel::writeBlob(size_t len, bool mutableCopy, WritableBlob* outBlob)
902 {
903     if (len > INT32_MAX) {
904         // don't accept size_t values which may have come from an
905         // inadvertent conversion from a negative int.
906         return BAD_VALUE;
907     }
908 
909     status_t status;
910     if (!mAllowFds || len <= BLOB_INPLACE_LIMIT) {
911         ALOGV("writeBlob: write in place");
912         status = writeInt32(BLOB_INPLACE);
913         if (status) return status;
914 
915         void* ptr = writeInplace(len);
916         if (!ptr) return NO_MEMORY;
917 
918         outBlob->init(-1, ptr, len, false);
919         return NO_ERROR;
920     }
921 
922     ALOGV("writeBlob: write to ashmem");
923     int fd = ashmem_create_region("Parcel Blob", len);
924     if (fd < 0) return NO_MEMORY;
925 
926     mBlobAshmemSize += len;
927 
928     int result = ashmem_set_prot_region(fd, PROT_READ | PROT_WRITE);
929     if (result < 0) {
930         status = result;
931     } else {
932         void* ptr = ::mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
933         if (ptr == MAP_FAILED) {
934             status = -errno;
935         } else {
936             if (!mutableCopy) {
937                 result = ashmem_set_prot_region(fd, PROT_READ);
938             }
939             if (result < 0) {
940                 status = result;
941             } else {
942                 status = writeInt32(mutableCopy ? BLOB_ASHMEM_MUTABLE : BLOB_ASHMEM_IMMUTABLE);
943                 if (!status) {
944                     status = writeFileDescriptor(fd, true /*takeOwnership*/);
945                     if (!status) {
946                         outBlob->init(fd, ptr, len, mutableCopy);
947                         return NO_ERROR;
948                     }
949                 }
950             }
951         }
952         ::munmap(ptr, len);
953     }
954     ::close(fd);
955     return status;
956 }
957 
writeDupImmutableBlobFileDescriptor(int fd)958 status_t Parcel::writeDupImmutableBlobFileDescriptor(int fd)
959 {
960     // Must match up with what's done in writeBlob.
961     if (!mAllowFds) return FDS_NOT_ALLOWED;
962     status_t status = writeInt32(BLOB_ASHMEM_IMMUTABLE);
963     if (status) return status;
964     return writeDupFileDescriptor(fd);
965 }
966 
write(const FlattenableHelperInterface & val)967 status_t Parcel::write(const FlattenableHelperInterface& val)
968 {
969     status_t err;
970 
971     // size if needed
972     const size_t len = val.getFlattenedSize();
973     const size_t fd_count = val.getFdCount();
974 
975     if ((len > INT32_MAX) || (fd_count > INT32_MAX)) {
976         // don't accept size_t values which may have come from an
977         // inadvertent conversion from a negative int.
978         return BAD_VALUE;
979     }
980 
981     err = this->writeInt32(len);
982     if (err) return err;
983 
984     err = this->writeInt32(fd_count);
985     if (err) return err;
986 
987     // payload
988     void* const buf = this->writeInplace(pad_size(len));
989     if (buf == NULL)
990         return BAD_VALUE;
991 
992     int* fds = NULL;
993     if (fd_count) {
994         fds = new int[fd_count];
995     }
996 
997     err = val.flatten(buf, len, fds, fd_count);
998     for (size_t i=0 ; i<fd_count && err==NO_ERROR ; i++) {
999         err = this->writeDupFileDescriptor( fds[i] );
1000     }
1001 
1002     if (fd_count) {
1003         delete [] fds;
1004     }
1005 
1006     return err;
1007 }
1008 
writeObject(const flat_binder_object & val,bool nullMetaData)1009 status_t Parcel::writeObject(const flat_binder_object& val, bool nullMetaData)
1010 {
1011     const bool enoughData = (mDataPos+sizeof(val)) <= mDataCapacity;
1012     const bool enoughObjects = mObjectsSize < mObjectsCapacity;
1013     if (enoughData && enoughObjects) {
1014 restart_write:
1015         *reinterpret_cast<flat_binder_object*>(mData+mDataPos) = val;
1016 
1017         // remember if it's a file descriptor
1018         if (val.type == BINDER_TYPE_FD) {
1019             if (!mAllowFds) {
1020                 // fail before modifying our object index
1021                 return FDS_NOT_ALLOWED;
1022             }
1023             mHasFds = mFdsKnown = true;
1024         }
1025 
1026         // Need to write meta-data?
1027         if (nullMetaData || val.binder != 0) {
1028             mObjects[mObjectsSize] = mDataPos;
1029             acquire_object(ProcessState::self(), val, this);
1030             mObjectsSize++;
1031         }
1032 
1033         return finishWrite(sizeof(flat_binder_object));
1034     }
1035 
1036     if (!enoughData) {
1037         const status_t err = growData(sizeof(val));
1038         if (err != NO_ERROR) return err;
1039     }
1040     if (!enoughObjects) {
1041         size_t newSize = ((mObjectsSize+2)*3)/2;
1042         if (newSize < mObjectsSize) return NO_MEMORY;   // overflow
1043         binder_size_t* objects = (binder_size_t*)realloc(mObjects, newSize*sizeof(binder_size_t));
1044         if (objects == NULL) return NO_MEMORY;
1045         mObjects = objects;
1046         mObjectsCapacity = newSize;
1047     }
1048 
1049     goto restart_write;
1050 }
1051 
writeNoException()1052 status_t Parcel::writeNoException()
1053 {
1054     return writeInt32(0);
1055 }
1056 
remove(size_t,size_t)1057 void Parcel::remove(size_t /*start*/, size_t /*amt*/)
1058 {
1059     LOG_ALWAYS_FATAL("Parcel::remove() not yet implemented!");
1060 }
1061 
read(void * outData,size_t len) const1062 status_t Parcel::read(void* outData, size_t len) const
1063 {
1064     if (len > INT32_MAX) {
1065         // don't accept size_t values which may have come from an
1066         // inadvertent conversion from a negative int.
1067         return BAD_VALUE;
1068     }
1069 
1070     if ((mDataPos+pad_size(len)) >= mDataPos && (mDataPos+pad_size(len)) <= mDataSize
1071             && len <= pad_size(len)) {
1072         memcpy(outData, mData+mDataPos, len);
1073         mDataPos += pad_size(len);
1074         ALOGV("read Setting data pos of %p to %zu", this, mDataPos);
1075         return NO_ERROR;
1076     }
1077     return NOT_ENOUGH_DATA;
1078 }
1079 
readInplace(size_t len) const1080 const void* Parcel::readInplace(size_t len) const
1081 {
1082     if (len > INT32_MAX) {
1083         // don't accept size_t values which may have come from an
1084         // inadvertent conversion from a negative int.
1085         return NULL;
1086     }
1087 
1088     if ((mDataPos+pad_size(len)) >= mDataPos && (mDataPos+pad_size(len)) <= mDataSize
1089             && len <= pad_size(len)) {
1090         const void* data = mData+mDataPos;
1091         mDataPos += pad_size(len);
1092         ALOGV("readInplace Setting data pos of %p to %zu", this, mDataPos);
1093         return data;
1094     }
1095     return NULL;
1096 }
1097 
1098 template<class T>
readAligned(T * pArg) const1099 status_t Parcel::readAligned(T *pArg) const {
1100     COMPILE_TIME_ASSERT_FUNCTION_SCOPE(PAD_SIZE_UNSAFE(sizeof(T)) == sizeof(T));
1101 
1102     if ((mDataPos+sizeof(T)) <= mDataSize) {
1103         const void* data = mData+mDataPos;
1104         mDataPos += sizeof(T);
1105         *pArg =  *reinterpret_cast<const T*>(data);
1106         return NO_ERROR;
1107     } else {
1108         return NOT_ENOUGH_DATA;
1109     }
1110 }
1111 
1112 template<class T>
readAligned() const1113 T Parcel::readAligned() const {
1114     T result;
1115     if (readAligned(&result) != NO_ERROR) {
1116         result = 0;
1117     }
1118 
1119     return result;
1120 }
1121 
1122 template<class T>
writeAligned(T val)1123 status_t Parcel::writeAligned(T val) {
1124     COMPILE_TIME_ASSERT_FUNCTION_SCOPE(PAD_SIZE_UNSAFE(sizeof(T)) == sizeof(T));
1125 
1126     if ((mDataPos+sizeof(val)) <= mDataCapacity) {
1127 restart_write:
1128         *reinterpret_cast<T*>(mData+mDataPos) = val;
1129         return finishWrite(sizeof(val));
1130     }
1131 
1132     status_t err = growData(sizeof(val));
1133     if (err == NO_ERROR) goto restart_write;
1134     return err;
1135 }
1136 
readInt32(int32_t * pArg) const1137 status_t Parcel::readInt32(int32_t *pArg) const
1138 {
1139     return readAligned(pArg);
1140 }
1141 
readInt32() const1142 int32_t Parcel::readInt32() const
1143 {
1144     return readAligned<int32_t>();
1145 }
1146 
readUint32(uint32_t * pArg) const1147 status_t Parcel::readUint32(uint32_t *pArg) const
1148 {
1149     return readAligned(pArg);
1150 }
1151 
readUint32() const1152 uint32_t Parcel::readUint32() const
1153 {
1154     return readAligned<uint32_t>();
1155 }
1156 
readInt64(int64_t * pArg) const1157 status_t Parcel::readInt64(int64_t *pArg) const
1158 {
1159     return readAligned(pArg);
1160 }
1161 
1162 
readInt64() const1163 int64_t Parcel::readInt64() const
1164 {
1165     return readAligned<int64_t>();
1166 }
1167 
readUint64(uint64_t * pArg) const1168 status_t Parcel::readUint64(uint64_t *pArg) const
1169 {
1170     return readAligned(pArg);
1171 }
1172 
readUint64() const1173 uint64_t Parcel::readUint64() const
1174 {
1175     return readAligned<uint64_t>();
1176 }
1177 
readPointer(uintptr_t * pArg) const1178 status_t Parcel::readPointer(uintptr_t *pArg) const
1179 {
1180     status_t ret;
1181     binder_uintptr_t ptr;
1182     ret = readAligned(&ptr);
1183     if (!ret)
1184         *pArg = ptr;
1185     return ret;
1186 }
1187 
readPointer() const1188 uintptr_t Parcel::readPointer() const
1189 {
1190     return readAligned<binder_uintptr_t>();
1191 }
1192 
1193 
readFloat(float * pArg) const1194 status_t Parcel::readFloat(float *pArg) const
1195 {
1196     return readAligned(pArg);
1197 }
1198 
1199 
readFloat() const1200 float Parcel::readFloat() const
1201 {
1202     return readAligned<float>();
1203 }
1204 
1205 #if defined(__mips__) && defined(__mips_hard_float)
1206 
readDouble(double * pArg) const1207 status_t Parcel::readDouble(double *pArg) const
1208 {
1209     union {
1210       double d;
1211       unsigned long long ll;
1212     } u;
1213     u.d = 0;
1214     status_t status;
1215     status = readAligned(&u.ll);
1216     *pArg = u.d;
1217     return status;
1218 }
1219 
readDouble() const1220 double Parcel::readDouble() const
1221 {
1222     union {
1223       double d;
1224       unsigned long long ll;
1225     } u;
1226     u.ll = readAligned<unsigned long long>();
1227     return u.d;
1228 }
1229 
1230 #else
1231 
readDouble(double * pArg) const1232 status_t Parcel::readDouble(double *pArg) const
1233 {
1234     return readAligned(pArg);
1235 }
1236 
readDouble() const1237 double Parcel::readDouble() const
1238 {
1239     return readAligned<double>();
1240 }
1241 
1242 #endif
1243 
readIntPtr(intptr_t * pArg) const1244 status_t Parcel::readIntPtr(intptr_t *pArg) const
1245 {
1246     return readAligned(pArg);
1247 }
1248 
1249 
readIntPtr() const1250 intptr_t Parcel::readIntPtr() const
1251 {
1252     return readAligned<intptr_t>();
1253 }
1254 
1255 
readCString() const1256 const char* Parcel::readCString() const
1257 {
1258     const size_t avail = mDataSize-mDataPos;
1259     if (avail > 0) {
1260         const char* str = reinterpret_cast<const char*>(mData+mDataPos);
1261         // is the string's trailing NUL within the parcel's valid bounds?
1262         const char* eos = reinterpret_cast<const char*>(memchr(str, 0, avail));
1263         if (eos) {
1264             const size_t len = eos - str;
1265             mDataPos += pad_size(len+1);
1266             ALOGV("readCString Setting data pos of %p to %zu", this, mDataPos);
1267             return str;
1268         }
1269     }
1270     return NULL;
1271 }
1272 
readString8() const1273 String8 Parcel::readString8() const
1274 {
1275     int32_t size = readInt32();
1276     // watch for potential int overflow adding 1 for trailing NUL
1277     if (size > 0 && size < INT32_MAX) {
1278         const char* str = (const char*)readInplace(size+1);
1279         if (str) return String8(str, size);
1280     }
1281     return String8();
1282 }
1283 
readString16() const1284 String16 Parcel::readString16() const
1285 {
1286     size_t len;
1287     const char16_t* str = readString16Inplace(&len);
1288     if (str) return String16(str, len);
1289     ALOGE("Reading a NULL string not supported here.");
1290     return String16();
1291 }
1292 
readString16Inplace(size_t * outLen) const1293 const char16_t* Parcel::readString16Inplace(size_t* outLen) const
1294 {
1295     int32_t size = readInt32();
1296     // watch for potential int overflow from size+1
1297     if (size >= 0 && size < INT32_MAX) {
1298         *outLen = size;
1299         const char16_t* str = (const char16_t*)readInplace((size+1)*sizeof(char16_t));
1300         if (str != NULL) {
1301             return str;
1302         }
1303     }
1304     *outLen = 0;
1305     return NULL;
1306 }
1307 
readStrongBinder() const1308 sp<IBinder> Parcel::readStrongBinder() const
1309 {
1310     sp<IBinder> val;
1311     unflatten_binder(ProcessState::self(), *this, &val);
1312     return val;
1313 }
1314 
readWeakBinder() const1315 wp<IBinder> Parcel::readWeakBinder() const
1316 {
1317     wp<IBinder> val;
1318     unflatten_binder(ProcessState::self(), *this, &val);
1319     return val;
1320 }
1321 
readExceptionCode() const1322 int32_t Parcel::readExceptionCode() const
1323 {
1324   int32_t exception_code = readAligned<int32_t>();
1325   if (exception_code == EX_HAS_REPLY_HEADER) {
1326     int32_t header_start = dataPosition();
1327     int32_t header_size = readAligned<int32_t>();
1328     // Skip over fat responses headers.  Not used (or propagated) in
1329     // native code
1330     setDataPosition(header_start + header_size);
1331     // And fat response headers are currently only used when there are no
1332     // exceptions, so return no error:
1333     return 0;
1334   }
1335   return exception_code;
1336 }
1337 
readNativeHandle() const1338 native_handle* Parcel::readNativeHandle() const
1339 {
1340     int numFds, numInts;
1341     status_t err;
1342     err = readInt32(&numFds);
1343     if (err != NO_ERROR) return 0;
1344     err = readInt32(&numInts);
1345     if (err != NO_ERROR) return 0;
1346 
1347     native_handle* h = native_handle_create(numFds, numInts);
1348     if (!h) {
1349         return 0;
1350     }
1351 
1352     for (int i=0 ; err==NO_ERROR && i<numFds ; i++) {
1353         h->data[i] = dup(readFileDescriptor());
1354         if (h->data[i] < 0) err = BAD_VALUE;
1355     }
1356     err = read(h->data + numFds, sizeof(int)*numInts);
1357     if (err != NO_ERROR) {
1358         native_handle_close(h);
1359         native_handle_delete(h);
1360         h = 0;
1361     }
1362     return h;
1363 }
1364 
1365 
readFileDescriptor() const1366 int Parcel::readFileDescriptor() const
1367 {
1368     const flat_binder_object* flat = readObject(true);
1369     if (flat) {
1370         switch (flat->type) {
1371             case BINDER_TYPE_FD:
1372                 //ALOGI("Returning file descriptor %ld from parcel %p", flat->handle, this);
1373                 return flat->handle;
1374         }
1375     }
1376     return BAD_TYPE;
1377 }
1378 
readBlob(size_t len,ReadableBlob * outBlob) const1379 status_t Parcel::readBlob(size_t len, ReadableBlob* outBlob) const
1380 {
1381     int32_t blobType;
1382     status_t status = readInt32(&blobType);
1383     if (status) return status;
1384 
1385     if (blobType == BLOB_INPLACE) {
1386         ALOGV("readBlob: read in place");
1387         const void* ptr = readInplace(len);
1388         if (!ptr) return BAD_VALUE;
1389 
1390         outBlob->init(-1, const_cast<void*>(ptr), len, false);
1391         return NO_ERROR;
1392     }
1393 
1394     ALOGV("readBlob: read from ashmem");
1395     bool isMutable = (blobType == BLOB_ASHMEM_MUTABLE);
1396     int fd = readFileDescriptor();
1397     if (fd == int(BAD_TYPE)) return BAD_VALUE;
1398 
1399     void* ptr = ::mmap(NULL, len, isMutable ? PROT_READ | PROT_WRITE : PROT_READ,
1400             MAP_SHARED, fd, 0);
1401     if (ptr == MAP_FAILED) return NO_MEMORY;
1402 
1403     outBlob->init(fd, ptr, len, isMutable);
1404     return NO_ERROR;
1405 }
1406 
read(FlattenableHelperInterface & val) const1407 status_t Parcel::read(FlattenableHelperInterface& val) const
1408 {
1409     // size
1410     const size_t len = this->readInt32();
1411     const size_t fd_count = this->readInt32();
1412 
1413     if (len > INT32_MAX) {
1414         // don't accept size_t values which may have come from an
1415         // inadvertent conversion from a negative int.
1416         return BAD_VALUE;
1417     }
1418 
1419     // payload
1420     void const* const buf = this->readInplace(pad_size(len));
1421     if (buf == NULL)
1422         return BAD_VALUE;
1423 
1424     int* fds = NULL;
1425     if (fd_count) {
1426         fds = new int[fd_count];
1427     }
1428 
1429     status_t err = NO_ERROR;
1430     for (size_t i=0 ; i<fd_count && err==NO_ERROR ; i++) {
1431         fds[i] = dup(this->readFileDescriptor());
1432         if (fds[i] < 0) {
1433             err = BAD_VALUE;
1434             ALOGE("dup() failed in Parcel::read, i is %zu, fds[i] is %d, fd_count is %zu, error: %s",
1435                 i, fds[i], fd_count, strerror(errno));
1436         }
1437     }
1438 
1439     if (err == NO_ERROR) {
1440         err = val.unflatten(buf, len, fds, fd_count);
1441     }
1442 
1443     if (fd_count) {
1444         delete [] fds;
1445     }
1446 
1447     return err;
1448 }
readObject(bool nullMetaData) const1449 const flat_binder_object* Parcel::readObject(bool nullMetaData) const
1450 {
1451     const size_t DPOS = mDataPos;
1452     if ((DPOS+sizeof(flat_binder_object)) <= mDataSize) {
1453         const flat_binder_object* obj
1454                 = reinterpret_cast<const flat_binder_object*>(mData+DPOS);
1455         mDataPos = DPOS + sizeof(flat_binder_object);
1456         if (!nullMetaData && (obj->cookie == 0 && obj->binder == 0)) {
1457             // When transferring a NULL object, we don't write it into
1458             // the object list, so we don't want to check for it when
1459             // reading.
1460             ALOGV("readObject Setting data pos of %p to %zu", this, mDataPos);
1461             return obj;
1462         }
1463 
1464         // Ensure that this object is valid...
1465         binder_size_t* const OBJS = mObjects;
1466         const size_t N = mObjectsSize;
1467         size_t opos = mNextObjectHint;
1468 
1469         if (N > 0) {
1470             ALOGV("Parcel %p looking for obj at %zu, hint=%zu",
1471                  this, DPOS, opos);
1472 
1473             // Start at the current hint position, looking for an object at
1474             // the current data position.
1475             if (opos < N) {
1476                 while (opos < (N-1) && OBJS[opos] < DPOS) {
1477                     opos++;
1478                 }
1479             } else {
1480                 opos = N-1;
1481             }
1482             if (OBJS[opos] == DPOS) {
1483                 // Found it!
1484                 ALOGV("Parcel %p found obj %zu at index %zu with forward search",
1485                      this, DPOS, opos);
1486                 mNextObjectHint = opos+1;
1487                 ALOGV("readObject Setting data pos of %p to %zu", this, mDataPos);
1488                 return obj;
1489             }
1490 
1491             // Look backwards for it...
1492             while (opos > 0 && OBJS[opos] > DPOS) {
1493                 opos--;
1494             }
1495             if (OBJS[opos] == DPOS) {
1496                 // Found it!
1497                 ALOGV("Parcel %p found obj %zu at index %zu with backward search",
1498                      this, DPOS, opos);
1499                 mNextObjectHint = opos+1;
1500                 ALOGV("readObject Setting data pos of %p to %zu", this, mDataPos);
1501                 return obj;
1502             }
1503         }
1504         ALOGW("Attempt to read object from Parcel %p at offset %zu that is not in the object list",
1505              this, DPOS);
1506     }
1507     return NULL;
1508 }
1509 
closeFileDescriptors()1510 void Parcel::closeFileDescriptors()
1511 {
1512     size_t i = mObjectsSize;
1513     if (i > 0) {
1514         //ALOGI("Closing file descriptors for %zu objects...", i);
1515     }
1516     while (i > 0) {
1517         i--;
1518         const flat_binder_object* flat
1519             = reinterpret_cast<flat_binder_object*>(mData+mObjects[i]);
1520         if (flat->type == BINDER_TYPE_FD) {
1521             //ALOGI("Closing fd: %ld", flat->handle);
1522             close(flat->handle);
1523         }
1524     }
1525 }
1526 
ipcData() const1527 uintptr_t Parcel::ipcData() const
1528 {
1529     return reinterpret_cast<uintptr_t>(mData);
1530 }
1531 
ipcDataSize() const1532 size_t Parcel::ipcDataSize() const
1533 {
1534     return (mDataSize > mDataPos ? mDataSize : mDataPos);
1535 }
1536 
ipcObjects() const1537 uintptr_t Parcel::ipcObjects() const
1538 {
1539     return reinterpret_cast<uintptr_t>(mObjects);
1540 }
1541 
ipcObjectsCount() const1542 size_t Parcel::ipcObjectsCount() const
1543 {
1544     return mObjectsSize;
1545 }
1546 
ipcSetDataReference(const uint8_t * data,size_t dataSize,const binder_size_t * objects,size_t objectsCount,release_func relFunc,void * relCookie)1547 void Parcel::ipcSetDataReference(const uint8_t* data, size_t dataSize,
1548     const binder_size_t* objects, size_t objectsCount, release_func relFunc, void* relCookie)
1549 {
1550     binder_size_t minOffset = 0;
1551     freeDataNoInit();
1552     mError = NO_ERROR;
1553     mData = const_cast<uint8_t*>(data);
1554     mDataSize = mDataCapacity = dataSize;
1555     //ALOGI("setDataReference Setting data size of %p to %lu (pid=%d)", this, mDataSize, getpid());
1556     mDataPos = 0;
1557     ALOGV("setDataReference Setting data pos of %p to %zu", this, mDataPos);
1558     mObjects = const_cast<binder_size_t*>(objects);
1559     mObjectsSize = mObjectsCapacity = objectsCount;
1560     mNextObjectHint = 0;
1561     mOwner = relFunc;
1562     mOwnerCookie = relCookie;
1563     for (size_t i = 0; i < mObjectsSize; i++) {
1564         binder_size_t offset = mObjects[i];
1565         if (offset < minOffset) {
1566             ALOGE("%s: bad object offset %" PRIu64 " < %" PRIu64 "\n",
1567                   __func__, (uint64_t)offset, (uint64_t)minOffset);
1568             mObjectsSize = 0;
1569             break;
1570         }
1571         minOffset = offset + sizeof(flat_binder_object);
1572     }
1573     scanForFds();
1574 }
1575 
print(TextOutput & to,uint32_t) const1576 void Parcel::print(TextOutput& to, uint32_t /*flags*/) const
1577 {
1578     to << "Parcel(";
1579 
1580     if (errorCheck() != NO_ERROR) {
1581         const status_t err = errorCheck();
1582         to << "Error: " << (void*)(intptr_t)err << " \"" << strerror(-err) << "\"";
1583     } else if (dataSize() > 0) {
1584         const uint8_t* DATA = data();
1585         to << indent << HexDump(DATA, dataSize()) << dedent;
1586         const binder_size_t* OBJS = objects();
1587         const size_t N = objectsCount();
1588         for (size_t i=0; i<N; i++) {
1589             const flat_binder_object* flat
1590                 = reinterpret_cast<const flat_binder_object*>(DATA+OBJS[i]);
1591             to << endl << "Object #" << i << " @ " << (void*)OBJS[i] << ": "
1592                 << TypeCode(flat->type & 0x7f7f7f00)
1593                 << " = " << flat->binder;
1594         }
1595     } else {
1596         to << "NULL";
1597     }
1598 
1599     to << ")";
1600 }
1601 
releaseObjects()1602 void Parcel::releaseObjects()
1603 {
1604     const sp<ProcessState> proc(ProcessState::self());
1605     size_t i = mObjectsSize;
1606     uint8_t* const data = mData;
1607     binder_size_t* const objects = mObjects;
1608     while (i > 0) {
1609         i--;
1610         const flat_binder_object* flat
1611             = reinterpret_cast<flat_binder_object*>(data+objects[i]);
1612         release_object(proc, *flat, this);
1613     }
1614 }
1615 
acquireObjects()1616 void Parcel::acquireObjects()
1617 {
1618     const sp<ProcessState> proc(ProcessState::self());
1619     size_t i = mObjectsSize;
1620     uint8_t* const data = mData;
1621     binder_size_t* const objects = mObjects;
1622     while (i > 0) {
1623         i--;
1624         const flat_binder_object* flat
1625             = reinterpret_cast<flat_binder_object*>(data+objects[i]);
1626         acquire_object(proc, *flat, this);
1627     }
1628 }
1629 
freeData()1630 void Parcel::freeData()
1631 {
1632     freeDataNoInit();
1633     initState();
1634 }
1635 
freeDataNoInit()1636 void Parcel::freeDataNoInit()
1637 {
1638     if (mOwner) {
1639         LOG_ALLOC("Parcel %p: freeing other owner data", this);
1640         //ALOGI("Freeing data ref of %p (pid=%d)", this, getpid());
1641         mOwner(this, mData, mDataSize, mObjects, mObjectsSize, mOwnerCookie);
1642     } else {
1643         LOG_ALLOC("Parcel %p: freeing allocated data", this);
1644         releaseObjects();
1645         if (mData) {
1646             LOG_ALLOC("Parcel %p: freeing with %zu capacity", this, mDataCapacity);
1647             pthread_mutex_lock(&gParcelGlobalAllocSizeLock);
1648             gParcelGlobalAllocSize -= mDataCapacity;
1649             gParcelGlobalAllocCount--;
1650             pthread_mutex_unlock(&gParcelGlobalAllocSizeLock);
1651             free(mData);
1652         }
1653         if (mObjects) free(mObjects);
1654     }
1655 }
1656 
growData(size_t len)1657 status_t Parcel::growData(size_t len)
1658 {
1659     if (len > INT32_MAX) {
1660         // don't accept size_t values which may have come from an
1661         // inadvertent conversion from a negative int.
1662         return BAD_VALUE;
1663     }
1664 
1665     size_t newSize = ((mDataSize+len)*3)/2;
1666     return (newSize <= mDataSize)
1667             ? (status_t) NO_MEMORY
1668             : continueWrite(newSize);
1669 }
1670 
restartWrite(size_t desired)1671 status_t Parcel::restartWrite(size_t desired)
1672 {
1673     if (desired > INT32_MAX) {
1674         // don't accept size_t values which may have come from an
1675         // inadvertent conversion from a negative int.
1676         return BAD_VALUE;
1677     }
1678 
1679     if (mOwner) {
1680         freeData();
1681         return continueWrite(desired);
1682     }
1683 
1684     uint8_t* data = (uint8_t*)realloc(mData, desired);
1685     if (!data && desired > mDataCapacity) {
1686         mError = NO_MEMORY;
1687         return NO_MEMORY;
1688     }
1689 
1690     releaseObjects();
1691 
1692     if (data) {
1693         LOG_ALLOC("Parcel %p: restart from %zu to %zu capacity", this, mDataCapacity, desired);
1694         pthread_mutex_lock(&gParcelGlobalAllocSizeLock);
1695         gParcelGlobalAllocSize += desired;
1696         gParcelGlobalAllocSize -= mDataCapacity;
1697         pthread_mutex_unlock(&gParcelGlobalAllocSizeLock);
1698         mData = data;
1699         mDataCapacity = desired;
1700     }
1701 
1702     mDataSize = mDataPos = 0;
1703     ALOGV("restartWrite Setting data size of %p to %zu", this, mDataSize);
1704     ALOGV("restartWrite Setting data pos of %p to %zu", this, mDataPos);
1705 
1706     free(mObjects);
1707     mObjects = NULL;
1708     mObjectsSize = mObjectsCapacity = 0;
1709     mNextObjectHint = 0;
1710     mHasFds = false;
1711     mFdsKnown = true;
1712     mAllowFds = true;
1713 
1714     return NO_ERROR;
1715 }
1716 
continueWrite(size_t desired)1717 status_t Parcel::continueWrite(size_t desired)
1718 {
1719     if (desired > INT32_MAX) {
1720         // don't accept size_t values which may have come from an
1721         // inadvertent conversion from a negative int.
1722         return BAD_VALUE;
1723     }
1724 
1725     // If shrinking, first adjust for any objects that appear
1726     // after the new data size.
1727     size_t objectsSize = mObjectsSize;
1728     if (desired < mDataSize) {
1729         if (desired == 0) {
1730             objectsSize = 0;
1731         } else {
1732             while (objectsSize > 0) {
1733                 if (mObjects[objectsSize-1] < desired)
1734                     break;
1735                 objectsSize--;
1736             }
1737         }
1738     }
1739 
1740     if (mOwner) {
1741         // If the size is going to zero, just release the owner's data.
1742         if (desired == 0) {
1743             freeData();
1744             return NO_ERROR;
1745         }
1746 
1747         // If there is a different owner, we need to take
1748         // posession.
1749         uint8_t* data = (uint8_t*)malloc(desired);
1750         if (!data) {
1751             mError = NO_MEMORY;
1752             return NO_MEMORY;
1753         }
1754         binder_size_t* objects = NULL;
1755 
1756         if (objectsSize) {
1757             objects = (binder_size_t*)calloc(objectsSize, sizeof(binder_size_t));
1758             if (!objects) {
1759                 free(data);
1760 
1761                 mError = NO_MEMORY;
1762                 return NO_MEMORY;
1763             }
1764 
1765             // Little hack to only acquire references on objects
1766             // we will be keeping.
1767             size_t oldObjectsSize = mObjectsSize;
1768             mObjectsSize = objectsSize;
1769             acquireObjects();
1770             mObjectsSize = oldObjectsSize;
1771         }
1772 
1773         if (mData) {
1774             memcpy(data, mData, mDataSize < desired ? mDataSize : desired);
1775         }
1776         if (objects && mObjects) {
1777             memcpy(objects, mObjects, objectsSize*sizeof(binder_size_t));
1778         }
1779         //ALOGI("Freeing data ref of %p (pid=%d)", this, getpid());
1780         mOwner(this, mData, mDataSize, mObjects, mObjectsSize, mOwnerCookie);
1781         mOwner = NULL;
1782 
1783         LOG_ALLOC("Parcel %p: taking ownership of %zu capacity", this, desired);
1784         pthread_mutex_lock(&gParcelGlobalAllocSizeLock);
1785         gParcelGlobalAllocSize += desired;
1786         gParcelGlobalAllocCount++;
1787         pthread_mutex_unlock(&gParcelGlobalAllocSizeLock);
1788 
1789         mData = data;
1790         mObjects = objects;
1791         mDataSize = (mDataSize < desired) ? mDataSize : desired;
1792         ALOGV("continueWrite Setting data size of %p to %zu", this, mDataSize);
1793         mDataCapacity = desired;
1794         mObjectsSize = mObjectsCapacity = objectsSize;
1795         mNextObjectHint = 0;
1796 
1797     } else if (mData) {
1798         if (objectsSize < mObjectsSize) {
1799             // Need to release refs on any objects we are dropping.
1800             const sp<ProcessState> proc(ProcessState::self());
1801             for (size_t i=objectsSize; i<mObjectsSize; i++) {
1802                 const flat_binder_object* flat
1803                     = reinterpret_cast<flat_binder_object*>(mData+mObjects[i]);
1804                 if (flat->type == BINDER_TYPE_FD) {
1805                     // will need to rescan because we may have lopped off the only FDs
1806                     mFdsKnown = false;
1807                 }
1808                 release_object(proc, *flat, this);
1809             }
1810             binder_size_t* objects =
1811                 (binder_size_t*)realloc(mObjects, objectsSize*sizeof(binder_size_t));
1812             if (objects) {
1813                 mObjects = objects;
1814             }
1815             mObjectsSize = objectsSize;
1816             mNextObjectHint = 0;
1817         }
1818 
1819         // We own the data, so we can just do a realloc().
1820         if (desired > mDataCapacity) {
1821             uint8_t* data = (uint8_t*)realloc(mData, desired);
1822             if (data) {
1823                 LOG_ALLOC("Parcel %p: continue from %zu to %zu capacity", this, mDataCapacity,
1824                         desired);
1825                 pthread_mutex_lock(&gParcelGlobalAllocSizeLock);
1826                 gParcelGlobalAllocSize += desired;
1827                 gParcelGlobalAllocSize -= mDataCapacity;
1828                 pthread_mutex_unlock(&gParcelGlobalAllocSizeLock);
1829                 mData = data;
1830                 mDataCapacity = desired;
1831             } else if (desired > mDataCapacity) {
1832                 mError = NO_MEMORY;
1833                 return NO_MEMORY;
1834             }
1835         } else {
1836             if (mDataSize > desired) {
1837                 mDataSize = desired;
1838                 ALOGV("continueWrite Setting data size of %p to %zu", this, mDataSize);
1839             }
1840             if (mDataPos > desired) {
1841                 mDataPos = desired;
1842                 ALOGV("continueWrite Setting data pos of %p to %zu", this, mDataPos);
1843             }
1844         }
1845 
1846     } else {
1847         // This is the first data.  Easy!
1848         uint8_t* data = (uint8_t*)malloc(desired);
1849         if (!data) {
1850             mError = NO_MEMORY;
1851             return NO_MEMORY;
1852         }
1853 
1854         if(!(mDataCapacity == 0 && mObjects == NULL
1855              && mObjectsCapacity == 0)) {
1856             ALOGE("continueWrite: %zu/%p/%zu/%zu", mDataCapacity, mObjects, mObjectsCapacity, desired);
1857         }
1858 
1859         LOG_ALLOC("Parcel %p: allocating with %zu capacity", this, desired);
1860         pthread_mutex_lock(&gParcelGlobalAllocSizeLock);
1861         gParcelGlobalAllocSize += desired;
1862         gParcelGlobalAllocCount++;
1863         pthread_mutex_unlock(&gParcelGlobalAllocSizeLock);
1864 
1865         mData = data;
1866         mDataSize = mDataPos = 0;
1867         ALOGV("continueWrite Setting data size of %p to %zu", this, mDataSize);
1868         ALOGV("continueWrite Setting data pos of %p to %zu", this, mDataPos);
1869         mDataCapacity = desired;
1870     }
1871 
1872     return NO_ERROR;
1873 }
1874 
initState()1875 void Parcel::initState()
1876 {
1877     LOG_ALLOC("Parcel %p: initState", this);
1878     mError = NO_ERROR;
1879     mData = 0;
1880     mDataSize = 0;
1881     mDataCapacity = 0;
1882     mDataPos = 0;
1883     ALOGV("initState Setting data size of %p to %zu", this, mDataSize);
1884     ALOGV("initState Setting data pos of %p to %zu", this, mDataPos);
1885     mObjects = NULL;
1886     mObjectsSize = 0;
1887     mObjectsCapacity = 0;
1888     mNextObjectHint = 0;
1889     mHasFds = false;
1890     mFdsKnown = true;
1891     mAllowFds = true;
1892     mOwner = NULL;
1893     mBlobAshmemSize = 0;
1894 }
1895 
scanForFds() const1896 void Parcel::scanForFds() const
1897 {
1898     bool hasFds = false;
1899     for (size_t i=0; i<mObjectsSize; i++) {
1900         const flat_binder_object* flat
1901             = reinterpret_cast<const flat_binder_object*>(mData + mObjects[i]);
1902         if (flat->type == BINDER_TYPE_FD) {
1903             hasFds = true;
1904             break;
1905         }
1906     }
1907     mHasFds = hasFds;
1908     mFdsKnown = true;
1909 }
1910 
getBlobAshmemSize() const1911 size_t Parcel::getBlobAshmemSize() const
1912 {
1913     return mBlobAshmemSize;
1914 }
1915 
1916 // --- Parcel::Blob ---
1917 
Blob()1918 Parcel::Blob::Blob() :
1919         mFd(-1), mData(NULL), mSize(0), mMutable(false) {
1920 }
1921 
~Blob()1922 Parcel::Blob::~Blob() {
1923     release();
1924 }
1925 
release()1926 void Parcel::Blob::release() {
1927     if (mFd != -1 && mData) {
1928         ::munmap(mData, mSize);
1929     }
1930     clear();
1931 }
1932 
init(int fd,void * data,size_t size,bool isMutable)1933 void Parcel::Blob::init(int fd, void* data, size_t size, bool isMutable) {
1934     mFd = fd;
1935     mData = data;
1936     mSize = size;
1937     mMutable = isMutable;
1938 }
1939 
clear()1940 void Parcel::Blob::clear() {
1941     mFd = -1;
1942     mData = NULL;
1943     mSize = 0;
1944     mMutable = false;
1945 }
1946 
1947 }; // namespace android
1948