Improve Error Reporting

Adds more meaningful error reporting where possible to the DrmEngine. Adds translation of CDM and OEMCrypto errors to Android errors. Bug: 8621516 Change-Id: Ibab8a8711c3929ed72870ec7e138cd42358d9fb3
2013-04-17 19:02:54 -07:00
parent 40abceaaed
commit ded298688c
9 changed files with 218 additions and 120 deletions
--- a/libwvdrmengine/include/WVErrors.h
+++ b/libwvdrmengine/include/WVErrors.h
@@ -0,0 +1,23 @@
+//
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+
+#ifndef WV_ERRORS_H_
+#define WV_ERRORS_H_
+
+#include "media/stagefright/MediaErrors.h"
+
+namespace wvdrm {
+
+using android::ERROR_DRM_VENDOR_MIN;
+
+enum {
+  kErrorNeedProvisioning       = ERROR_DRM_VENDOR_MIN,
+  kErrorDeviceRevoked          = ERROR_DRM_VENDOR_MIN + 1,
+  kErrorIncorrectBufferSize    = ERROR_DRM_VENDOR_MIN + 2,
+  kErrorCDMGeneric             = ERROR_DRM_VENDOR_MIN + 3,
+};
+
+} // namespace wvdrm
+
+#endif // WV_ERRORS_H_
--- a/libwvdrmengine/include/mapErrors-inl.h
+++ b/libwvdrmengine/include/mapErrors-inl.h
@@ -0,0 +1,49 @@
+//
+// Copyright 2013 Google Inc. All Rights Reserved.
+//
+
+#ifndef WV_MAP_ERRORS_H_
+#define WV_MAP_ERRORS_H_
+
+#include "media/stagefright/MediaErrors.h"
+#include "utils/Errors.h"
+#include "wv_cdm_types.h"
+#include "WVErrors.h"
+
+namespace wvdrm {
+
+static android::status_t mapCdmResponseType(wvcdm::CdmResponseType res) {
+  switch (res) {
+    case wvcdm::NO_ERROR:
+    case wvcdm::KEY_ADDED:
+    case wvcdm::KEY_MESSAGE:
+    case wvcdm::KEY_CANCELED:
+      // KEY_ADDED, KEY_MESSAGE, and KEY_CANCELLED are all alternative
+      // success messages for certain CDM methods instead of NO_ERROR.
+      return android::OK;
+    case wvcdm::NEED_KEY:
+      return android::ERROR_DRM_NO_LICENSE;
+    case wvcdm::NEED_PROVISIONING:
+      return kErrorNeedProvisioning;
+    case wvcdm::DEVICE_REVOKED:
+      return kErrorDeviceRevoked;
+    case wvcdm::KEY_ERROR:
+      // KEY_ERROR is used by the CDM to mean just about any kind of error, not
+      // just license errors, so it is mapped to the generic response.
+      return kErrorCDMGeneric;
+    case wvcdm::UNKNOWN_ERROR:
+      return android::ERROR_DRM_UNKNOWN;
+  }
+
+  // Return here instead of as a default case so that the compiler will warn
+  // us if we forget to include an enum member in the switch statement.
+  return android::UNKNOWN_ERROR;
+}
+
+static inline bool isCdmResponseTypeSuccess(wvcdm::CdmResponseType res) {
+  return mapCdmResponseType(res) == android::OK;
+}
+
+} // namespace wvdrm
+
+#endif // WV_MAP_ERRORS_H_
--- a/libwvdrmengine/mediacrypto/Android.mk
+++ b/libwvdrmengine/mediacrypto/Android.mk
@@ -12,6 +12,7 @@ LOCAL_C_INCLUDES := \
  frameworks/native/include \
  vendor/widevine/libwvdrmengine/cdm/core/include \
  vendor/widevine/libwvdrmengine/cdm/include \
+  vendor/widevine/libwvdrmengine/include \
  vendor/widevine/libwvdrmengine/mediacrypto/include \

 LOCAL_MODULE := libwvdrmcryptoplugin
--- a/libwvdrmengine/mediacrypto/include/WVCryptoPlugin.h
+++ b/libwvdrmengine/mediacrypto/include/WVCryptoPlugin.h
@@ -5,6 +5,8 @@
 #ifndef WV_CRYPTO_PLUGIN_H_
 #define WV_CRYPTO_PLUGIN_H_

+#include <stdint.h>
+
 #include "media/hardware/CryptoAPI.h"
 #include "media/stagefright/foundation/ABase.h"
 #include "media/stagefright/foundation/AString.h"
@@ -26,13 +28,14 @@ class WVCryptoPlugin : public android::CryptoPlugin {
                          void* dstPtr, android::AString* errorDetailMsg);

 private:
-  wvcdm::CdmSessionId configureTestMode(const void* data, size_t size);
  DISALLOW_EVIL_CONSTRUCTORS(WVCryptoPlugin);

  wvcdm::WvContentDecryptionModule* const mCDM;

  bool mTestMode;
  const wvcdm::CdmSessionId mSessionId;
+
+  wvcdm::CdmSessionId configureTestMode(const void* data, size_t size);
 };

 } // namespace wvdrm
--- a/libwvdrmengine/mediacrypto/src/WVCryptoPlugin.cpp
+++ b/libwvdrmengine/mediacrypto/src/WVCryptoPlugin.cpp
@@ -11,12 +11,13 @@
 #include <string.h>
 #include <string>
 #include <vector>
-#include <openssl/sha.h>

+#include "mapErrors-inl.h"
+#include "media/stagefright/MediaErrors.h"
+#include "openssl/sha.h"
 #include "utils/Errors.h"
 #include "utils/String8.h"
 #include "wv_cdm_constants.h"
-#include "media/stagefright/MediaErrors.h"

 namespace wvdrm {

@@ -26,11 +27,12 @@ using namespace wvcdm;

 WVCryptoPlugin::WVCryptoPlugin(const void* data, size_t size,
                               WvContentDecryptionModule* cdm)
-    : mCDM(cdm),
+  : mCDM(cdm),
    mTestMode(false),
    mSessionId(configureTestMode(data, size)) {}

-wvcdm::CdmSessionId WVCryptoPlugin::configureTestMode(const void* data, size_t size) {
+wvcdm::CdmSessionId WVCryptoPlugin::configureTestMode(const void* data,
+                                                      size_t size) {
  wvcdm::CdmSessionId sessionId(static_cast<const char *>(data), size);
  size_t index = sessionId.find("test_mode");
  if (index != string::npos) {
@@ -40,7 +42,6 @@ wvcdm::CdmSessionId WVCryptoPlugin::configureTestMode(const void* data, size_t s
  return sessionId;
 }

-
 bool WVCryptoPlugin::requiresSecureDecoderComponent(const char* mime) const {
  if (!strncasecmp(mime, "video/", 6)) {
    // Type is video, so query CDM to see if we require a secure decoder.
@@ -48,7 +49,7 @@ bool WVCryptoPlugin::requiresSecureDecoderComponent(const char* mime) const {

    CdmResponseType res = mCDM->QueryStatus(&status);

-    if (res != wvcdm::NO_ERROR) {
+    if (!isCdmResponseTypeSuccess(res)) {
      ALOGE("Error querying CDM status: %u", res);
      return false;
    }
@@ -70,7 +71,7 @@ ssize_t WVCryptoPlugin::decrypt(bool secure, const uint8_t key[KEY_ID_SIZE],
                                size_t numSubSamples, void* dstPtr,
                                AString* errorDetailMsg) {
  if (mode != kMode_Unencrypted && mode != kMode_AES_CTR) {
-    return BAD_TYPE;
+    return ERROR_DRM_CANNOT_HANDLE;
  }

  // If the caller requested secure decrypt, verify that we can comply.
@@ -79,12 +80,12 @@ ssize_t WVCryptoPlugin::decrypt(bool secure, const uint8_t key[KEY_ID_SIZE],

    CdmResponseType res = mCDM->QueryStatus(&status);

-    if (res != wvcdm::NO_ERROR) {
+    if (!isCdmResponseTypeSuccess(res)) {
      ALOGE("Error querying CDM status: %u", res);
-      return PERMISSION_DENIED;
+      return ERROR_DRM_CANNOT_HANDLE;
    } else if (status[QUERY_KEY_SECURITY_LEVEL] !=
               QUERY_VALUE_SECURITY_LEVEL_L1) {
-      return PERMISSION_DENIED;
+      return ERROR_DRM_CANNOT_HANDLE;
    }
  }

@@ -102,7 +103,7 @@ ssize_t WVCryptoPlugin::decrypt(bool secure, const uint8_t key[KEY_ID_SIZE],
    const SubSample &subSample = subSamples[i];

    if (mode == kMode_Unencrypted && subSample.mNumBytesOfEncryptedData != 0) {
-      return -EINVAL;
+      return ERROR_DRM_DECRYPT;
    }

    // "Decrypt" any unencrypted data.  Per the ISO-CENC standard, clear data
@@ -113,10 +114,10 @@ ssize_t WVCryptoPlugin::decrypt(bool secure, const uint8_t key[KEY_ID_SIZE],
                                          subSample.mNumBytesOfClearData,
                                          ivVector, 0, dest + offset);

-      if (res != wvcdm::NO_ERROR) {
+      if (!isCdmResponseTypeSuccess(res)) {
        ALOGE("Decrypt error result in session %s during unencrypted block: %d",
              mSessionId.c_str(), res);
-        return -EINVAL;
+        return mapCdmResponseType(res);
      }

      offset += subSample.mNumBytesOfClearData;
@@ -130,10 +131,10 @@ ssize_t WVCryptoPlugin::decrypt(bool secure, const uint8_t key[KEY_ID_SIZE],
                                          subSample.mNumBytesOfEncryptedData,
                                          ivVector, encrypted_offset % 16, dest + offset);

-      if (res != wvcdm::NO_ERROR) {
+      if (!isCdmResponseTypeSuccess(res)) {
        ALOGE("Decrypt error result in session %s during encrypted block: %d",
              mSessionId.c_str(), res);
-        return -EINVAL;
+        return mapCdmResponseType(res);
      }

      offset += subSample.mNumBytesOfEncryptedData;
--- a/libwvdrmengine/mediadrm/Android.mk
+++ b/libwvdrmengine/mediadrm/Android.mk
@@ -11,6 +11,7 @@ LOCAL_C_INCLUDES := \
  frameworks/native/include \
  vendor/widevine/libwvdrmengine/cdm/core/include \
  vendor/widevine/libwvdrmengine/cdm/include \
+  vendor/widevine/libwvdrmengine/include \
  vendor/widevine/libwvdrmengine/mediadrm/include \
  vendor/widevine/libwvdrmengine/oemcrypto/include \

--- a/libwvdrmengine/mediadrm/include/WVDrmPlugin.h
+++ b/libwvdrmengine/mediadrm/include/WVDrmPlugin.h
@@ -5,6 +5,7 @@
 #ifndef WV_DRM_PLUGIN_H_
 #define WV_DRM_PLUGIN_H_

+#include <stdint.h>
 #include <map>

 #include "media/drm/DrmAPI.h"
@@ -159,6 +160,8 @@ class WVDrmPlugin : public android::DrmPlugin,
  WvContentDecryptionModule* mCDM;
  WVGenericCryptoInterface* mCrypto;
  map<CdmSessionId, CryptoSession> mCryptoSessions;
+
+  static status_t mapOEMCryptoResult(OEMCryptoResult res);
 };

 } // namespace wvdrm
--- a/libwvdrmengine/mediadrm/include/WVGenericCryptoInterface.h
+++ b/libwvdrmengine/mediadrm/include/WVGenericCryptoInterface.h
@@ -5,6 +5,8 @@
 #ifndef WV_GENERIC_CRYPTO_INTERFACE_H_
 #define WV_GENERIC_CRYPTO_INTERFACE_H_

+#include <stdint.h>
+
 #include "OEMCryptoCENC.h"

 namespace wvdrm {
--- a/libwvdrmengine/mediadrm/src/WVDrmPlugin.cpp
+++ b/libwvdrmengine/mediadrm/src/WVDrmPlugin.cpp
@@ -12,6 +12,7 @@
 #include <string>
 #include <vector>

+#include "mapErrors-inl.h"
 #include "media/stagefright/MediaErrors.h"
 #include "utils/Errors.h"
 #include "wv_cdm_constants.h"
@@ -45,8 +46,8 @@ status_t WVDrmPlugin::openSession(Vector<uint8_t>& sessionId) {
  CdmSessionId cdmSessionId;
  CdmResponseType res = mCDM->OpenSession("com.widevine", &cdmSessionId);

-  if (res != wvcdm::NO_ERROR) {
-    return android::UNKNOWN_ERROR;
+  if (!isCdmResponseTypeSuccess(res)) {
+    return mapCdmResponseType(res);
  }

  bool success = false;
@@ -58,15 +59,18 @@ status_t WVDrmPlugin::openSession(Vector<uint8_t>& sessionId) {
    // Construct a CryptoSession
    CdmQueryMap info;

-    CdmResponseType res = mCDM->QueryKeyControlInfo(cdmSessionId, &info);
+    res = mCDM->QueryKeyControlInfo(cdmSessionId, &info);

-    if (res == wvcdm::NO_ERROR && info.count(QUERY_KEY_OEMCRYPTO_SESSION_ID)) {
+    if (isCdmResponseTypeSuccess(res) &&
+        info.count(QUERY_KEY_OEMCRYPTO_SESSION_ID)) {
      OEMCrypto_SESSION oecSessionId;
      istringstream(info[QUERY_KEY_OEMCRYPTO_SESSION_ID]) >> oecSessionId;

      mCryptoSessions[cdmSessionId] = CryptoSession(oecSessionId);

      success = true;
+    } else {
+      ALOGE("Unable to query key control info.");
    }
  } else {
    ALOGE("Received failure when trying to attach WVDrmPlugin as an event"
@@ -87,7 +91,14 @@ status_t WVDrmPlugin::openSession(Vector<uint8_t>& sessionId) {

    mCDM->CloseSession(cdmSessionId);

-    return android::UNKNOWN_ERROR;
+    if (!isCdmResponseTypeSuccess(res)) {
+      // We got an error code we can return.
+      return mapCdmResponseType(res);
+    } else {
+      // We got a failure that did not give us an error code, such as a failure
+      // of AttachEventListener() or the key being missing from the map.
+      return kErrorCDMGeneric;
+    }
  }
 }

@@ -95,12 +106,11 @@ status_t WVDrmPlugin::closeSession(const Vector<uint8_t>& sessionId) {
  CdmSessionId cdmSessionId(sessionId.begin(), sessionId.end());
  CdmResponseType res = mCDM->CloseSession(cdmSessionId);

-  if (res == wvcdm::NO_ERROR) {
+  if (isCdmResponseTypeSuccess(res)) {
    mCryptoSessions.erase(cdmSessionId);
-    return android::OK;
-  } else {
-    return android::UNKNOWN_ERROR;
  }
+
+  return mapCdmResponseType(res);
 }

 status_t WVDrmPlugin::getKeyRequest(
@@ -117,7 +127,7 @@ status_t WVDrmPlugin::getKeyRequest(
  } else if (keyType == kKeyType_Streaming) {
    cdmLicenseType = kLicenseTypeStreaming;
  } else {
-    return BAD_TYPE;
+    return android::ERROR_DRM_CANNOT_HANDLE;
  }

  CdmSessionId cdmSessionId(sessionId.begin(), sessionId.end());
@@ -140,17 +150,15 @@ status_t WVDrmPlugin::getKeyRequest(
                                                 cdmLicenseType,
                                                 cdmParameters, &keyRequest);

-  if (res != wvcdm::KEY_MESSAGE) {
-    return android::UNKNOWN_ERROR;
+  if (isCdmResponseTypeSuccess(res)) {
+    defaultUrl.clear();
+
+    request.clear();
+    request.appendArray(reinterpret_cast<const uint8_t*>(keyRequest.data()),
+                        keyRequest.size());
  }

-  defaultUrl.clear();
-
-  request.clear();
-  request.appendArray(reinterpret_cast<const uint8_t*>(keyRequest.data()),
-                      keyRequest.size());
-
-  return android::OK;
+  return mapCdmResponseType(res);
 }

 status_t WVDrmPlugin::provideKeyResponse(
@@ -163,11 +171,7 @@ status_t WVDrmPlugin::provideKeyResponse(

  CdmResponseType res = mCDM->AddKey(cdmSessionId, cdmResponse);

-  if (res == wvcdm::KEY_ADDED || res == wvcdm::NO_ERROR) {
-    return android::OK;
-  } else {
-    return android::UNKNOWN_ERROR;
-  }
+  return mapCdmResponseType(res);
 }

 status_t WVDrmPlugin::removeKeys(const Vector<uint8_t>& keySetId) {
@@ -189,24 +193,22 @@ status_t WVDrmPlugin::queryKeyStatus(

  CdmResponseType res = mCDM->QueryKeyStatus(cdmSessionId, &cdmLicenseInfo);

-  if (res != wvcdm::NO_ERROR) {
-    return android::UNKNOWN_ERROR;
+  if (isCdmResponseTypeSuccess(res)) {
+    infoMap.clear();
+    for (CdmQueryMap::const_iterator iter = cdmLicenseInfo.begin();
+         iter != cdmLicenseInfo.end();
+         ++iter) {
+      const string& cdmKey = iter->first;
+      const string& cdmValue = iter->second;
+
+      String8 key(cdmKey.data(), cdmKey.size());
+      String8 value(cdmValue.data(), cdmValue.size());
+
+      infoMap.add(key, value);
+    }
  }

-  infoMap.clear();
-  for (CdmQueryMap::const_iterator iter = cdmLicenseInfo.begin();
-       iter != cdmLicenseInfo.end();
-       ++iter) {
-    const string& cdmKey = iter->first;
-    const string& cdmValue = iter->second;
-
-    String8 key(cdmKey.data(), cdmKey.size());
-    String8 value(cdmValue.data(), cdmValue.size());
-
-    infoMap.add(key, value);
-  }
-
-  return android::OK;
+  return mapCdmResponseType(res);
 }

 status_t WVDrmPlugin::getProvisionRequest(Vector<uint8_t>& request,
@@ -217,19 +219,17 @@ status_t WVDrmPlugin::getProvisionRequest(Vector<uint8_t>& request,
  CdmResponseType res = mCDM->GetProvisioningRequest(&cdmProvisionRequest,
                                                     &cdmDefaultUrl);

-  if (res != wvcdm::NO_ERROR) {
-    return android::UNKNOWN_ERROR;
+  if (isCdmResponseTypeSuccess(res)) {
+    request.clear();
+    request.appendArray(reinterpret_cast<const uint8_t*>(
+                            cdmProvisionRequest.data()),
+                        cdmProvisionRequest.size());
+
+    defaultUrl.clear();
+    defaultUrl.setTo(cdmDefaultUrl.data(), cdmDefaultUrl.size());
  }

-  request.clear();
-  request.appendArray(reinterpret_cast<const uint8_t*>(
-                          cdmProvisionRequest.data()),
-                      cdmProvisionRequest.size());
-
-  defaultUrl.clear();
-  defaultUrl.setTo(cdmDefaultUrl.data(), cdmDefaultUrl.size());
-
-  return android::OK;
+  return mapCdmResponseType(res);
 }

 status_t WVDrmPlugin::provideProvisionResponse(
@@ -239,11 +239,7 @@ status_t WVDrmPlugin::provideProvisionResponse(

  CdmResponseType res = mCDM->HandleProvisioningResponse(cdmResponse);

-  if (res == wvcdm::NO_ERROR) {
-    return android::OK;
-  } else {
-    return android::UNKNOWN_ERROR;
-  }
+  return mapCdmResponseType(res);
 }

 status_t WVDrmPlugin::getSecureStops(List<Vector<uint8_t> >& secureStops) {
@@ -251,24 +247,22 @@ status_t WVDrmPlugin::getSecureStops(List<Vector<uint8_t> >& secureStops) {

  CdmResponseType res = mCDM->GetSecureStops(&cdmSecureStops);

-  if (res != wvcdm::NO_ERROR) {
-    return android::UNKNOWN_ERROR;
+  if (isCdmResponseTypeSuccess(res)) {
+    secureStops.clear();
+    for (CdmSecureStops::const_iterator iter = cdmSecureStops.begin();
+         iter != cdmSecureStops.end();
+         ++iter) {
+      const string& cdmStop = *iter;
+
+      Vector<uint8_t> stop;
+      stop.appendArray(reinterpret_cast<const uint8_t*>(cdmStop.data()),
+                       cdmStop.size());
+
+      secureStops.push_back(stop);
+    }
  }

-  secureStops.clear();
-  for (CdmSecureStops::const_iterator iter = cdmSecureStops.begin();
-       iter != cdmSecureStops.end();
-       ++iter) {
-    const string& cdmStop = *iter;
-
-    Vector<uint8_t> stop;
-    stop.appendArray(reinterpret_cast<const uint8_t*>(cdmStop.data()),
-                     cdmStop.size());
-
-    secureStops.push_back(stop);
-  }
-
-  return android::OK;
+  return mapCdmResponseType(res);
 }

 status_t WVDrmPlugin::releaseSecureStops(const Vector<uint8_t>& ssRelease) {
@@ -276,11 +270,7 @@ status_t WVDrmPlugin::releaseSecureStops(const Vector<uint8_t>& ssRelease) {

  CdmResponseType res = mCDM->ReleaseSecureStops(cdmMessage);

-  if (res == wvcdm::NO_ERROR) {
-    return android::OK;
-  } else {
-    return android::UNKNOWN_ERROR;
-  }
+  return mapCdmResponseType(res);
 }

 status_t WVDrmPlugin::getPropertyString(const String8& name,
@@ -298,12 +288,12 @@ status_t WVDrmPlugin::getPropertyString(const String8& name,

    CdmResponseType res = mCDM->QueryStatus(&status);

-    if (res != wvcdm::NO_ERROR) {
+    if (!isCdmResponseTypeSuccess(res)) {
      ALOGE("Error querying CDM status: %u", res);
-      return android::UNKNOWN_ERROR;
+      return mapCdmResponseType(res);
    } else if (!status.count(QUERY_KEY_SECURITY_LEVEL)) {
      ALOGE("CDM did not report a security level");
-      return android::UNKNOWN_ERROR;
+      return kErrorCDMGeneric;
    }

    const string& securityLevel = status[QUERY_KEY_SECURITY_LEVEL];
@@ -312,7 +302,7 @@ status_t WVDrmPlugin::getPropertyString(const String8& name,
    value.append(securityLevel.data(), securityLevel.size());
  } else {
    ALOGE("App requested unknown property %s", name.string());
-    return android::ERROR_UNSUPPORTED;
+    return android::ERROR_DRM_CANNOT_HANDLE;
  }

  return android::OK;
@@ -325,12 +315,12 @@ status_t WVDrmPlugin::getPropertyByteArray(const String8& name,

    CdmResponseType res = mCDM->QueryStatus(&status);

-    if (res != wvcdm::NO_ERROR) {
+    if (!isCdmResponseTypeSuccess(res)) {
      ALOGE("Error querying CDM status: %u", res);
-      return android::UNKNOWN_ERROR;
+      return mapCdmResponseType(res);
    } else if (!status.count(QUERY_KEY_DEVICE_ID)) {
      ALOGE("CDM did not report a unique ID");
-      return android::UNKNOWN_ERROR;
+      return kErrorCDMGeneric;
    }

    const string& uniqueId = status[QUERY_KEY_DEVICE_ID];
@@ -340,7 +330,7 @@ status_t WVDrmPlugin::getPropertyByteArray(const String8& name,
                      uniqueId.size());
  } else {
    ALOGE("App requested unknown property %s", name.string());
-    return android::ERROR_UNSUPPORTED;
+    return android::ERROR_DRM_CANNOT_HANDLE;
  }

  return android::OK;
@@ -348,12 +338,12 @@ status_t WVDrmPlugin::getPropertyByteArray(const String8& name,

 status_t WVDrmPlugin::setPropertyString(const String8& name,
                                        const String8& value) {
-  return android::ERROR_UNSUPPORTED;
+  return android::ERROR_DRM_CANNOT_HANDLE;
 }

 status_t WVDrmPlugin::setPropertyByteArray(const String8& name,
                                           const Vector<uint8_t>& value) {
-  return android::ERROR_UNSUPPORTED;
+  return android::ERROR_DRM_CANNOT_HANDLE;
 }

 status_t WVDrmPlugin::setCipherAlgorithm(const Vector<uint8_t>& sessionId,
@@ -361,7 +351,7 @@ status_t WVDrmPlugin::setCipherAlgorithm(const Vector<uint8_t>& sessionId,
  CdmSessionId cdmSessionId(sessionId.begin(), sessionId.end());

  if (!mCryptoSessions.count(cdmSessionId)) {
-    return android::NO_INIT;
+    return android::ERROR_DRM_SESSION_NOT_OPENED;
  }

  CryptoSession& cryptoSession = mCryptoSessions[cdmSessionId];
@@ -369,7 +359,7 @@ status_t WVDrmPlugin::setCipherAlgorithm(const Vector<uint8_t>& sessionId,
  if (algorithm == "AES/CBC/NoPadding") {
    cryptoSession.setCipherAlgorithm(OEMCrypto_AES_CBC_128_NO_PADDING);
  } else {
-    return android::BAD_VALUE;
+    return android::ERROR_DRM_CANNOT_HANDLE;
  }

  return android::OK;
@@ -380,7 +370,7 @@ status_t WVDrmPlugin::setMacAlgorithm(const Vector<uint8_t>& sessionId,
  CdmSessionId cdmSessionId(sessionId.begin(), sessionId.end());

  if (!mCryptoSessions.count(cdmSessionId)) {
-    return android::NO_INIT;
+    return android::ERROR_DRM_SESSION_NOT_OPENED;
  }

  CryptoSession& cryptoSession = mCryptoSessions[cdmSessionId];
@@ -388,7 +378,7 @@ status_t WVDrmPlugin::setMacAlgorithm(const Vector<uint8_t>& sessionId,
  if (algorithm == "HmacSHA256") {
    cryptoSession.setMacAlgorithm(OEMCrypto_HMAC_SHA256);
  } else {
-    return android::BAD_VALUE;
+    return android::ERROR_DRM_CANNOT_HANDLE;
  }

  return android::OK;
@@ -402,7 +392,7 @@ status_t WVDrmPlugin::encrypt(const Vector<uint8_t>& sessionId,
  CdmSessionId cdmSessionId(sessionId.begin(), sessionId.end());

  if (!mCryptoSessions.count(cdmSessionId)) {
-    return android::NO_INIT;
+    return android::ERROR_DRM_SESSION_NOT_OPENED;
  }

  const CryptoSession& cryptoSession = mCryptoSessions[cdmSessionId];
@@ -416,7 +406,7 @@ status_t WVDrmPlugin::encrypt(const Vector<uint8_t>& sessionId,

  if (res != OEMCrypto_SUCCESS) {
    ALOGE("OEMCrypto_SelectKey failed with %u", res);
-    return android::UNKNOWN_ERROR;
+    return mapOEMCryptoResult(res);
  }

  output.resize(input.size());
@@ -429,7 +419,7 @@ status_t WVDrmPlugin::encrypt(const Vector<uint8_t>& sessionId,
    return android::OK;
  } else {
    ALOGE("OEMCrypto_Generic_Encrypt failed with %u", res);
-    return android::UNKNOWN_ERROR;
+    return mapOEMCryptoResult(res);
  }
 }

@@ -441,7 +431,7 @@ status_t WVDrmPlugin::decrypt(const Vector<uint8_t>& sessionId,
  CdmSessionId cdmSessionId(sessionId.begin(), sessionId.end());

  if (!mCryptoSessions.count(cdmSessionId)) {
-    return android::NO_INIT;
+    return android::ERROR_DRM_SESSION_NOT_OPENED;
  }

  const CryptoSession& cryptoSession = mCryptoSessions[cdmSessionId];
@@ -455,7 +445,7 @@ status_t WVDrmPlugin::decrypt(const Vector<uint8_t>& sessionId,

  if (res != OEMCrypto_SUCCESS) {
    ALOGE("OEMCrypto_SelectKey failed with %u", res);
-    return android::UNKNOWN_ERROR;
+    return mapOEMCryptoResult(res);
  }

  output.resize(input.size());
@@ -468,7 +458,7 @@ status_t WVDrmPlugin::decrypt(const Vector<uint8_t>& sessionId,
    return android::OK;
  } else {
    ALOGE("OEMCrypto_Generic_Decrypt failed with %u", res);
-    return android::UNKNOWN_ERROR;
+    return mapOEMCryptoResult(res);
  }
 }

@@ -479,7 +469,7 @@ status_t WVDrmPlugin::sign(const Vector<uint8_t>& sessionId,
  CdmSessionId cdmSessionId(sessionId.begin(), sessionId.end());

  if (!mCryptoSessions.count(cdmSessionId)) {
-    return android::NO_INIT;
+    return android::ERROR_DRM_SESSION_NOT_OPENED;
  }

  const CryptoSession& cryptoSession = mCryptoSessions[cdmSessionId];
@@ -493,7 +483,7 @@ status_t WVDrmPlugin::sign(const Vector<uint8_t>& sessionId,

  if (res != OEMCrypto_SUCCESS) {
    ALOGE("OEMCrypto_SelectKey failed with %u", res);
-    return android::UNKNOWN_ERROR;
+    return mapOEMCryptoResult(res);
  }

  size_t signatureSize = 0;
@@ -505,7 +495,11 @@ status_t WVDrmPlugin::sign(const Vector<uint8_t>& sessionId,
  if (res != OEMCrypto_ERROR_SHORT_BUFFER) {
    ALOGE("OEMCrypto_Generic_Sign failed with %u when requesting signature "
          "size", res);
-    return android::UNKNOWN_ERROR;
+    if (res != OEMCrypto_SUCCESS) {
+      return mapOEMCryptoResult(res);
+    } else {
+      return android::ERROR_DRM_UNKNOWN;
+    }
  }

  signature.resize(signatureSize);
@@ -518,7 +512,7 @@ status_t WVDrmPlugin::sign(const Vector<uint8_t>& sessionId,
    return android::OK;
  } else {
    ALOGE("OEMCrypto_Generic_Sign failed with %u", res);
-    return android::UNKNOWN_ERROR;
+    return mapOEMCryptoResult(res);
  }
 }

@@ -530,7 +524,7 @@ status_t WVDrmPlugin::verify(const Vector<uint8_t>& sessionId,
  CdmSessionId cdmSessionId(sessionId.begin(), sessionId.end());

  if (!mCryptoSessions.count(cdmSessionId)) {
-    return android::NO_INIT;
+    return android::ERROR_DRM_SESSION_NOT_OPENED;
  }

  const CryptoSession& cryptoSession = mCryptoSessions[cdmSessionId];
@@ -544,7 +538,7 @@ status_t WVDrmPlugin::verify(const Vector<uint8_t>& sessionId,

  if (res != OEMCrypto_SUCCESS) {
    ALOGE("OEMCrypto_SelectKey failed with %u", res);
-    return android::UNKNOWN_ERROR;
+    return mapOEMCryptoResult(res);
  }

  res = mCrypto->verify(cryptoSession.oecSessionId(), message.array(),
@@ -559,7 +553,7 @@ status_t WVDrmPlugin::verify(const Vector<uint8_t>& sessionId,
    return android::OK;
  } else {
    ALOGE("OEMCrypto_Generic_Verify failed with %u", res);
-    return android::UNKNOWN_ERROR;
+    return mapOEMCryptoResult(res);
  }
 }

@@ -587,4 +581,25 @@ void WVDrmPlugin::onEvent(const CdmSessionId& cdmSessionId,
  sendEvent(eventType, 0, &sessionId, NULL);
 }

+status_t WVDrmPlugin::mapOEMCryptoResult(OEMCryptoResult res) {
+  // Note that we only cover those errors that OEMCryptoCENC.h states may be
+  // returned by the generic crypto methods.
+  switch (res) {
+    case OEMCrypto_SUCCESS:
+      return android::OK;
+    case OEMCrypto_ERROR_SIGNATURE_FAILURE:
+      return android::ERROR_DRM_TAMPER_DETECTED;
+    case OEMCrypto_ERROR_SHORT_BUFFER:
+      return kErrorIncorrectBufferSize;
+    case OEMCrypto_ERROR_NO_DEVICE_KEY:
+      return kErrorNeedProvisioning;
+    case OEMCrypto_ERROR_INVALID_SESSION:
+      return android::ERROR_DRM_SESSION_NOT_OPENED;
+    case OEMCrypto_ERROR_UNKNOWN_FAILURE:
+      return android::ERROR_DRM_UNKNOWN;
+    default:
+      return android::UNKNOWN_ERROR;
+  }
+}
+
 }  // namespace wvdrm