Modular DRM for MediaPlayer

Bug:  34559906
Test: Manual through the test app

Change-Id: I286f9ff199c34563b7b8643de725f8d1534ea06c
diff --git a/media/libmediaplayerservice/nuplayer/NuPlayerDrm.cpp b/media/libmediaplayerservice/nuplayer/NuPlayerDrm.cpp
new file mode 100644
index 0000000..cb9a5f8
--- /dev/null
+++ b/media/libmediaplayerservice/nuplayer/NuPlayerDrm.cpp
@@ -0,0 +1,366 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+//#define LOG_NDEBUG 0
+#define LOG_TAG "NuPlayerDrm"
+
+#include "NuPlayerDrm.h"
+
+#include <binder/IServiceManager.h>
+#include <media/IMediaDrmService.h>
+#include <utils/Log.h>
+
+
+namespace android {
+
+// static helpers - internal
+
+sp<IDrm> NuPlayerDrm::CreateDrm(status_t *pstatus)
+{
+    status_t &status = *pstatus;
+    sp<IServiceManager> sm = defaultServiceManager();
+    sp<IBinder> binder = sm->getService(String16("media.drm"));
+    ALOGV("CreateDrm binder %p", (binder != NULL ? binder.get() : 0));
+
+    sp<IMediaDrmService> service = interface_cast<IMediaDrmService>(binder);
+    if (service == NULL) {
+        ALOGE("CreateDrm failed at IMediaDrmService");
+        return NULL;
+    }
+
+    sp<IDrm> drm = service->makeDrm();
+    if (drm == NULL) {
+        ALOGE("CreateDrm failed at makeDrm");
+        return NULL;
+    }
+
+    // this is before plugin creation so NO_INIT is fine
+    status = drm->initCheck();
+    if (status != OK && status != NO_INIT) {
+        ALOGE("CreateDrm failed drm->initCheck(): %d", status);
+        return NULL;
+    }
+    return drm;
+}
+
+sp<ICrypto> NuPlayerDrm::createCrypto(status_t *pstatus)
+{
+    status_t &status = *pstatus;
+    sp<IServiceManager> sm = defaultServiceManager();
+    sp<IBinder> binder = sm->getService(String16("media.drm"));
+
+    sp<IMediaDrmService> service = interface_cast<IMediaDrmService>(binder);
+    if (service == NULL) {
+        status = UNKNOWN_ERROR;
+        ALOGE("CreateCrypto failed at IMediaDrmService");
+        return NULL;
+    }
+
+    sp<ICrypto> crypto = service->makeCrypto();
+    if (crypto == NULL) {
+        status = UNKNOWN_ERROR;
+        ALOGE("createCrypto failed");
+        return NULL;
+    }
+
+    // this is before plugin creation so NO_INIT is fine
+    status = crypto->initCheck();
+    if (status != OK && status != NO_INIT) {
+        ALOGE("createCrypto failed crypto->initCheck(): %d", status);
+        return NULL;
+    }
+
+    return crypto;
+}
+
+Vector<DrmUUID> NuPlayerDrm::parsePSSH(const void *pssh, size_t psshsize)
+{
+    Vector<DrmUUID> drmSchemes, empty;
+    const int DATALEN_SIZE = 4;
+
+    // the format of the buffer is 1 or more of:
+    //    {
+    //        16 byte uuid
+    //        4 byte data length N
+    //        N bytes of data
+    //    }
+    // Determine the number of entries in the source data.
+    // Since we got the data from stagefright, we trust it is valid and properly formatted.
+
+    const uint8_t *data = (const uint8_t*)pssh;
+    size_t len = psshsize;
+    size_t numentries = 0;
+    while (len > 0) {
+        if (len < DrmUUID::UUID_SIZE) {
+            ALOGE("ParsePSSH: invalid PSSH data");
+            return empty;
+        }
+
+        const uint8_t *uuidPtr = data;
+
+        // skip uuid
+        data += DrmUUID::UUID_SIZE;
+        len -= DrmUUID::UUID_SIZE;
+
+        // get data length
+        if (len < DATALEN_SIZE) {
+            ALOGE("ParsePSSH: invalid PSSH data");
+            return empty;
+        }
+
+        uint32_t datalen = *((uint32_t*)data);
+        data += DATALEN_SIZE;
+        len -= DATALEN_SIZE;
+
+        if (len < datalen) {
+            ALOGE("ParsePSSH: invalid PSSH data");
+            return empty;
+        }
+
+        // skip the data
+        data += datalen;
+        len -= datalen;
+
+        DrmUUID _uuid(uuidPtr);
+        drmSchemes.add(_uuid);
+
+        ALOGV("ParsePSSH[%zu]: %s: %s", numentries,
+                _uuid.toHexString().string(),
+                DrmUUID::arrayToHex(data, datalen).string()
+             );
+
+        numentries++;
+    }
+
+    return drmSchemes;
+}
+
+Vector<DrmUUID> NuPlayerDrm::getSupportedDrmSchemes(const void *pssh, size_t psshsize)
+{
+    Vector<DrmUUID> psshDRMs = parsePSSH(pssh, psshsize);
+
+    Vector<DrmUUID> supportedDRMs;
+     // temporary DRM object for crypto Scheme enquiry (without creating a plugin)
+    status_t status = OK;
+    sp<IDrm> drm = CreateDrm(&status);
+    if (drm != NULL) {
+        for (size_t i = 0; i < psshDRMs.size(); i++) {
+            DrmUUID uuid = psshDRMs[i];
+            if (drm->isCryptoSchemeSupported(uuid.ptr(), String8()))
+                supportedDRMs.add(uuid);
+        }
+
+        drm.clear();
+    } else {
+        ALOGE("getSupportedDrmSchemes: Can't create Drm obj: %d", status);
+    }
+
+    ALOGV("getSupportedDrmSchemes: psshDRMs: %zu supportedDRMs: %zu",
+            psshDRMs.size(), supportedDRMs.size());
+
+    return supportedDRMs;
+}
+
+// static helpers - public
+
+sp<ICrypto> NuPlayerDrm::createCryptoAndPlugin(const uint8_t uuid[16],
+        const Vector<uint8_t> &drmSessionId, status_t &status)
+{
+    // Extra check
+    if (drmSessionId.isEmpty()) {
+        status = INVALID_OPERATION;
+        ALOGE("createCryptoAndPlugin: Failed. Empty drmSessionId. status: %d", status);
+        return NULL;
+    }
+
+    status = OK;
+    sp<ICrypto> crypto = createCrypto(&status);
+    if (crypto == NULL) {
+        ALOGE("createCryptoAndPlugin: createCrypto failed. status: %d", status);
+        return NULL;
+    }
+    ALOGV("createCryptoAndPlugin: createCrypto succeeded");
+
+    status = crypto->createPlugin(uuid, drmSessionId.array(), drmSessionId.size());
+    if (status != OK) {
+        ALOGE("createCryptoAndPlugin: createCryptoPlugin failed. status: %d", status);
+        // crypto will clean itself when leaving the current scope
+        return NULL;
+    }
+
+    return crypto;
+}
+
+// Parcel has only private copy constructor so passing it in rather than returning
+void NuPlayerDrm::retrieveDrmInfo(const void *pssh, size_t psshsize,
+        const Vector<String8> &mimes_in, Parcel *parcel)
+{
+    // 0) Make mimes a vector of unique items while keeping the original order; video first
+    Vector<String8> mimes;
+    for (size_t j = 0; j < mimes_in.size(); j++) {
+        String8 mime = mimes_in[j];
+        bool exists = false;
+        for (size_t i = 0; i < mimes.size() && !exists; i++) {
+            if (mimes[i] == mime) {
+                exists = true;
+            }
+        } // for i
+
+        if (!exists) {
+            mimes.add(mime);
+        }
+    } // for j
+
+
+    // 1) PSSH bytes
+    parcel->writeUint32(psshsize);
+    parcel->writeByteArray(psshsize, (const uint8_t*)pssh);
+
+    ALOGV("retrieveDrmInfo: MEDIA_DRM_INFO  PSSH: size: %zu %s", psshsize,
+            DrmUUID::arrayToHex((uint8_t*)pssh, psshsize).string());
+
+    // 2) supportedDRMs
+    Vector<DrmUUID> supportedDRMs = getSupportedDrmSchemes(pssh, psshsize);
+    parcel->writeUint32(supportedDRMs.size());
+    for (size_t i = 0; i < supportedDRMs.size(); i++) {
+        DrmUUID uuid = supportedDRMs[i];
+        parcel->writeByteArray(DrmUUID::UUID_SIZE, uuid.ptr());
+
+        ALOGV("retrieveDrmInfo: MEDIA_DRM_INFO  supportedScheme[%zu] %s", i,
+                uuid.toHexString().string());
+    }
+
+    // TODO: remove mimes after it's removed from Java DrmInfo
+    // 3) mimes
+    parcel->writeUint32(mimes.size());
+    for (size_t i = 0; i < mimes.size(); i++) {
+        // writing as String16 so the Java framework side can unpack it to Java String
+        String16 mime(mimes[i]);
+        parcel->writeString16(mime);
+
+        ALOGV("retrieveDrmInfo: MEDIA_DRM_INFO  MIME[%zu] %s",
+                i, mimes[i].string());
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////
+/// Helpers for NuPlayerDecoder
+////////////////////////////////////////////////////////////////////////////////////////////
+
+NuPlayerDrm::CryptoInfo *NuPlayerDrm::makeCryptoInfo(
+        int numSubSamples,
+        uint8_t key[kBlockSize],
+        uint8_t iv[kBlockSize],
+        CryptoPlugin::Mode mode,
+        size_t *clearbytes,
+        size_t *encryptedbytes)
+{
+    // size needed to store all the crypto data
+    size_t cryptosize = sizeof(CryptoInfo) +
+                        sizeof(CryptoPlugin::SubSample) * numSubSamples;
+    CryptoInfo *ret = (CryptoInfo*) malloc(cryptosize);
+    if (ret == NULL) {
+        ALOGE("couldn't allocate %zu bytes", cryptosize);
+        return NULL;
+    }
+    ret->numSubSamples = numSubSamples;
+    memcpy(ret->key, key, kBlockSize);
+    memcpy(ret->iv, iv, kBlockSize);
+    ret->mode = mode;
+    ret->pattern.mEncryptBlocks = 0;
+    ret->pattern.mSkipBlocks = 0;
+    ret->subSamples = (CryptoPlugin::SubSample*)(ret + 1);
+    CryptoPlugin::SubSample *subSamples = ret->subSamples;
+
+    for (int i = 0; i < numSubSamples; i++) {
+        subSamples[i].mNumBytesOfClearData = (clearbytes == NULL) ? 0 : clearbytes[i];
+        subSamples[i].mNumBytesOfEncryptedData = (encryptedbytes == NULL) ?
+                                                  0 :
+                                                  encryptedbytes[i];
+    }
+
+    return ret;
+}
+
+NuPlayerDrm::CryptoInfo *NuPlayerDrm::getSampleCryptoInfo(sp<MetaData> meta)
+{
+    uint32_t type;
+    const void *crypteddata;
+    size_t cryptedsize;
+
+    if (meta == NULL) {
+        ALOGE("getSampleCryptoInfo: Unexpected. No meta data for sample.");
+        return NULL;
+    }
+
+    if (!meta->findData(kKeyEncryptedSizes, &type, &crypteddata, &cryptedsize)) {
+        return NULL;
+    }
+    size_t numSubSamples = cryptedsize / sizeof(size_t);
+
+    if (numSubSamples <= 0) {
+        ALOGE("getSampleCryptoInfo INVALID numSubSamples: %zu", numSubSamples);
+        return NULL;
+    }
+
+    const void *cleardata;
+    size_t clearsize;
+    if (meta->findData(kKeyPlainSizes, &type, &cleardata, &clearsize)) {
+        if (clearsize != cryptedsize) {
+            // The two must be of the same length.
+            ALOGE("getSampleCryptoInfo mismatch cryptedsize: %zu != clearsize: %zu",
+                    cryptedsize, clearsize);
+            return NULL;
+        }
+    }
+
+    const void *key;
+    size_t keysize;
+    if (meta->findData(kKeyCryptoKey, &type, &key, &keysize)) {
+        if (keysize != kBlockSize) {
+            ALOGE("getSampleCryptoInfo Keys must be %zu bytes in length: %zu",
+                    kBlockSize, keysize);
+            // Keys must be 16 bytes in length.
+            return NULL;
+        }
+    }
+
+    const void *iv;
+    size_t ivsize;
+    if (meta->findData(kKeyCryptoIV, &type, &iv, &ivsize)) {
+        if (ivsize != kBlockSize) {
+            ALOGE("getSampleCryptoInfo IV must be %zu bytes in length: %zu",
+                    kBlockSize, ivsize);
+            // IVs must be 16 bytes in length.
+            return NULL;
+        }
+    }
+
+    int32_t mode;
+    if (!meta->findInt32(kKeyCryptoMode, &mode)) {
+        mode = CryptoPlugin::kMode_AES_CTR;
+    }
+
+    return makeCryptoInfo(numSubSamples,
+            (uint8_t*) key,
+            (uint8_t*) iv,
+            (CryptoPlugin::Mode)mode,
+            (size_t*) cleardata,
+            (size_t*) crypteddata);
+}
+
+}   // namespace android
+