1 /*
2  * Copyright (C) 2017 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_NDEBUG 0
18 #define LOG_TAG "CasManager"
19 #include "CasManager.h"
20 
21 #include <android/hardware/cas/1.0/ICas.h>
22 #include <android/hardware/cas/1.0/IMediaCasService.h>
23 #include <android/hardware/cas/native/1.0/IDescrambler.h>
24 #include <hidl/HidlSupport.h>
25 #include <media/stagefright/foundation/ABitReader.h>
26 #include <utils/Log.h>
27 
28 namespace android {
29 
30 using hardware::hidl_vec;
31 using hardware::Return;
32 using namespace hardware::cas::V1_0;
33 using namespace hardware::cas::native::V1_0;
34 
35 struct ATSParser::CasManager::ProgramCasManager : public RefBase {
36     ProgramCasManager(unsigned programNumber, const CADescriptor &descriptor);
37     ProgramCasManager(unsigned programNumber);
38 
39     bool addStream(unsigned elementaryPID, const CADescriptor &descriptor);
40 
41     status_t setMediaCas(const sp<ICas> &cas, PidToSessionMap &sessionMap);
42 
43     bool getCasSession(unsigned elementaryPID,
44             sp<IDescrambler> *descrambler, std::vector<uint8_t> *sessionId) const;
45 
46     void closeAllSessions(const sp<ICas>& cas);
47 
48 private:
49     struct CasSession {
CasSessionandroid::ATSParser::CasManager::ProgramCasManager::CasSession50         CasSession() {}
CasSessionandroid::ATSParser::CasManager::ProgramCasManager::CasSession51         CasSession(const CADescriptor &descriptor) :
52             mCADescriptor(descriptor) {}
53 
54         CADescriptor mCADescriptor;
55         std::vector<uint8_t> mSessionId;
56         sp<IDescrambler> mDescrambler;
57     };
58     status_t initSession(
59             const sp<ICas>& cas,
60             PidToSessionMap &sessionMap,
61             CasSession *session);
62     void closeSession(const sp<ICas>& cas, const CasSession &casSession);
63 
64     unsigned mProgramNumber;
65     bool mHasProgramCas;
66     CasSession mProgramCas;
67     KeyedVector<unsigned, CasSession> mStreamPidToCasMap;
68 };
69 
ProgramCasManager(unsigned programNumber,const CADescriptor & descriptor)70 ATSParser::CasManager::ProgramCasManager::ProgramCasManager(
71         unsigned programNumber, const CADescriptor &descriptor) :
72     mProgramNumber(programNumber),
73     mHasProgramCas(true),
74     mProgramCas(descriptor) {}
75 
ProgramCasManager(unsigned programNumber)76 ATSParser::CasManager::ProgramCasManager::ProgramCasManager(
77         unsigned programNumber) :
78     mProgramNumber(programNumber),
79     mHasProgramCas(false) {}
80 
addStream(unsigned elementaryPID,const CADescriptor & descriptor)81 bool ATSParser::CasManager::ProgramCasManager::addStream(
82         unsigned elementaryPID, const CADescriptor &descriptor) {
83     ssize_t index = mStreamPidToCasMap.indexOfKey(elementaryPID);
84     if (index >= 0) {
85         return false;
86     }
87     ALOGV("addStream: program=%d, elementaryPID=%d, CA_system_ID=0x%x",
88             mProgramNumber, elementaryPID, descriptor.mSystemID);
89     mStreamPidToCasMap.add(elementaryPID, CasSession(descriptor));
90     return true;
91 }
92 
setMediaCas(const sp<ICas> & cas,PidToSessionMap & sessionMap)93 status_t ATSParser::CasManager::ProgramCasManager::setMediaCas(
94         const sp<ICas> &cas, PidToSessionMap &sessionMap) {
95     if (mHasProgramCas) {
96         return initSession(cas, sessionMap, &mProgramCas);
97     }
98     // TODO: share session among streams that has identical CA_descriptors.
99     // For now, we open one session for each stream that has CA_descriptor.
100     for (size_t index = 0; index < mStreamPidToCasMap.size(); index++) {
101         status_t err = initSession(
102                 cas, sessionMap, &mStreamPidToCasMap.editValueAt(index));
103         if (err != OK) {
104             return err;
105         }
106     }
107     return OK;
108 }
109 
getCasSession(unsigned elementaryPID,sp<IDescrambler> * descrambler,std::vector<uint8_t> * sessionId) const110 bool ATSParser::CasManager::ProgramCasManager::getCasSession(
111         unsigned elementaryPID, sp<IDescrambler> *descrambler,
112         std::vector<uint8_t> *sessionId) const {
113     if (mHasProgramCas) {
114         *descrambler = mProgramCas.mDescrambler;
115         *sessionId = mProgramCas.mSessionId;
116         return true;
117     }
118     ssize_t index = mStreamPidToCasMap.indexOfKey(elementaryPID);
119     if (index < 0) {
120         return false;
121     }
122 
123     *descrambler = mStreamPidToCasMap[index].mDescrambler;
124     *sessionId = mStreamPidToCasMap[index].mSessionId;
125     return true;
126 }
127 
initSession(const sp<ICas> & cas,PidToSessionMap & sessionMap,CasSession * session)128 status_t ATSParser::CasManager::ProgramCasManager::initSession(
129          const sp<ICas>& cas,
130          PidToSessionMap &sessionMap,
131          CasSession *session) {
132     sp<IMediaCasService> casService = IMediaCasService::getService("default");
133     if (casService == NULL) {
134         ALOGE("Cannot obtain IMediaCasService");
135         return NO_INIT;
136     }
137 
138     Status status;
139     sp<IDescrambler> descrambler;
140     sp<IDescramblerBase> descramblerBase;
141     Return<Status> returnStatus(Status::OK);
142     Return<sp<IDescramblerBase> > returnDescrambler(NULL);
143     std::vector<uint8_t> sessionId;
144     const CADescriptor &descriptor = session->mCADescriptor;
145 
146     auto returnVoid = cas->openSession(
147             [&status, &sessionId] (Status _status, const hidl_vec<uint8_t>& _sessionId) {
148                 status = _status;
149                 sessionId = _sessionId;
150             });
151     if (!returnVoid.isOk() || status != Status::OK) {
152         ALOGE("Failed to open session: trans=%s, status=%d",
153                 returnVoid.description().c_str(), status);
154         goto l_fail;
155     }
156 
157     returnStatus = cas->setSessionPrivateData(sessionId, descriptor.mPrivateData);
158     if (!returnStatus.isOk() || returnStatus != Status::OK) {
159         ALOGE("Failed to set private data: trans=%s, status=%d",
160                 returnStatus.description().c_str(), (Status)returnStatus);
161         goto l_fail;
162     }
163 
164     returnDescrambler = casService->createDescrambler(descriptor.mSystemID);
165     if (!returnDescrambler.isOk()) {
166         ALOGE("Failed to create descrambler: trans=%s",
167                 returnDescrambler.description().c_str());
168         goto l_fail;
169     }
170     descramblerBase = (sp<IDescramblerBase>) returnDescrambler;
171     if (descramblerBase == NULL) {
172         ALOGE("Failed to create descrambler: null ptr");
173         goto l_fail;
174     }
175 
176     returnStatus = descramblerBase->setMediaCasSession(sessionId);
177     if (!returnStatus.isOk() || (Status) returnStatus != Status::OK) {
178         ALOGE("Failed to init descrambler: : trans=%s, status=%d",
179                 returnStatus.description().c_str(), (Status) returnStatus);
180         goto l_fail;
181     }
182 
183     descrambler = IDescrambler::castFrom(descramblerBase);
184     if (descrambler == NULL) {
185         ALOGE("Failed to cast from IDescramblerBase to IDescrambler");
186         goto l_fail;
187     }
188 
189     session->mSessionId = sessionId;
190     session->mDescrambler = descrambler;
191     sessionMap.add(descriptor.mPID, sessionId);
192 
193     return OK;
194 
195 l_fail:
196     if (!sessionId.empty()) {
197         cas->closeSession(sessionId);
198     }
199     if (descramblerBase != NULL) {
200         descramblerBase->release();
201     }
202     return NO_INIT;
203 }
204 
closeSession(const sp<ICas> & cas,const CasSession & casSession)205 void ATSParser::CasManager::ProgramCasManager::closeSession(
206         const sp<ICas>& cas, const CasSession &casSession) {
207     if (casSession.mDescrambler != NULL) {
208         casSession.mDescrambler->release();
209     }
210     if (!casSession.mSessionId.empty()) {
211         cas->closeSession(casSession.mSessionId);
212     }
213 }
214 
closeAllSessions(const sp<ICas> & cas)215 void ATSParser::CasManager::ProgramCasManager::closeAllSessions(
216         const sp<ICas>& cas) {
217     if (mHasProgramCas) {
218         closeSession(cas, mProgramCas);
219     }
220     for (size_t index = 0; index < mStreamPidToCasMap.size(); index++) {
221         closeSession(cas, mStreamPidToCasMap.editValueAt(index));
222     }
223 }
224 
225 ////////////////////////////////////////////////////////////////////////////////
226 
CasManager()227 ATSParser::CasManager::CasManager() : mSystemId(-1) {}
228 
~CasManager()229 ATSParser::CasManager::~CasManager() {
230     // Explictly close the sessions opened by us, since the CAS object is owned
231     // by the app and may not go away after the parser is destroyed, and the app
232     // may not have information about the sessions.
233     if (mICas != NULL) {
234         for (size_t index = 0; index < mProgramCasMap.size(); index++) {
235             mProgramCasMap.editValueAt(index)->closeAllSessions(mICas);
236         }
237     }
238 }
239 
setSystemId(int32_t CA_system_ID)240 bool ATSParser::CasManager::setSystemId(int32_t CA_system_ID) {
241     if (mSystemId == -1) {
242         // Verify the CA_system_ID is within range on the first program
243         if (CA_system_ID < 0 || CA_system_ID > 0xffff) {
244             ALOGE("Invalid CA_system_id: %d", CA_system_ID);
245             return false;
246         }
247         mSystemId = CA_system_ID;
248     } else if (mSystemId != CA_system_ID) {
249         // All sessions need to be under the same CA system
250         ALOGE("Multiple CA systems not allowed: %d vs %d",
251                 mSystemId, CA_system_ID);
252         return false;
253     }
254     return true;
255 }
256 
setMediaCas(const sp<ICas> & cas)257 status_t ATSParser::CasManager::setMediaCas(const sp<ICas> &cas) {
258     if (cas == NULL) {
259         ALOGE("setMediaCas: received NULL object");
260         return BAD_VALUE;
261     }
262     if (mICas != NULL) {
263         ALOGW("setMediaCas: already set");
264         return ALREADY_EXISTS;
265     }
266     for (size_t index = 0; index < mProgramCasMap.size(); index++) {
267         status_t err;
268         if ((err = mProgramCasMap.editValueAt(
269                 index)->setMediaCas(cas, mCAPidToSessionIdMap)) != OK) {
270             return err;
271         }
272     }
273     mICas = cas;
274     return OK;
275 }
276 
addProgram(unsigned programNumber,const CADescriptor & descriptor)277 bool ATSParser::CasManager::addProgram(
278         unsigned programNumber, const CADescriptor &descriptor) {
279     if (!setSystemId(descriptor.mSystemID)) {
280         return false;
281     }
282 
283     ssize_t index = mProgramCasMap.indexOfKey(programNumber);
284     if (index < 0) {
285         ALOGV("addProgram: programNumber=%d, CA_system_ID=0x%x",
286                 programNumber, descriptor.mSystemID);
287         mProgramCasMap.add(programNumber,
288                 new ProgramCasManager(programNumber, descriptor));
289         mCAPidSet.insert(descriptor.mPID);
290     }
291     return true;
292 }
293 
addStream(unsigned programNumber,unsigned elementaryPID,const CADescriptor & descriptor)294 bool ATSParser::CasManager::addStream(
295         unsigned programNumber, unsigned elementaryPID,
296         const CADescriptor &descriptor) {
297     if (!setSystemId(descriptor.mSystemID)) {
298         return false;
299     }
300 
301     ssize_t index = mProgramCasMap.indexOfKey(programNumber);
302     sp<ProgramCasManager> programCasManager;
303     if (index < 0) {
304         ALOGV("addProgram (no CADescriptor): programNumber=%d", programNumber);
305         programCasManager = new ProgramCasManager(programNumber);
306         mProgramCasMap.add(programNumber, programCasManager);
307     } else {
308         programCasManager = mProgramCasMap.editValueAt(index);
309     }
310     if (programCasManager->addStream(elementaryPID, descriptor)) {
311         mCAPidSet.insert(descriptor.mPID);
312     }
313     return true;
314 }
315 
getCasInfo(unsigned programNumber,unsigned elementaryPID,int32_t * systemId,sp<IDescrambler> * descrambler,std::vector<uint8_t> * sessionId) const316 bool ATSParser::CasManager::getCasInfo(
317         unsigned programNumber, unsigned elementaryPID,
318         int32_t *systemId, sp<IDescrambler> *descrambler,
319         std::vector<uint8_t> *sessionId) const {
320     ssize_t index = mProgramCasMap.indexOfKey(programNumber);
321     if (index < 0) {
322         return false;
323     }
324     *systemId = mSystemId;
325     return mProgramCasMap[index]->getCasSession(
326             elementaryPID, descrambler, sessionId);
327 }
328 
isCAPid(unsigned pid)329 bool ATSParser::CasManager::isCAPid(unsigned pid) {
330     return mCAPidSet.find(pid) != mCAPidSet.end();
331 }
332 
parsePID(ABitReader * br,unsigned pid)333 bool ATSParser::CasManager::parsePID(ABitReader *br, unsigned pid) {
334     ssize_t index = mCAPidToSessionIdMap.indexOfKey(pid);
335     if (index < 0) {
336         return false;
337     }
338     hidl_vec<uint8_t> ecm;
339     ecm.setToExternal((uint8_t*)br->data(), br->numBitsLeft() / 8);
340     auto returnStatus = mICas->processEcm(mCAPidToSessionIdMap[index], ecm);
341     if (!returnStatus.isOk() || (Status) returnStatus != Status::OK) {
342         ALOGE("Failed to process ECM: trans=%s, status=%d",
343                 returnStatus.description().c_str(), (Status) returnStatus);
344     }
345     return true; // handled
346 }
347 
348 }  // namespace android
349