Provide fallback for keymaster implementations
Some implementations won't support ECDSA or DSA, so provide a fallback
for them by using the softkeymaster implementation. This will allow us
to universally support ECDSA and DSA on all platforms regardless of HAL
version.
Bug: 10600582
Change-Id: Ib842816cc1415ec00abb7d22c8e9b6bbe58f6a86
diff --git a/keystore/Android.mk b/keystore/Android.mk
index f495f34..47b7e84 100644
--- a/keystore/Android.mk
+++ b/keystore/Android.mk
@@ -20,7 +20,15 @@
LOCAL_CFLAGS := -Wall -Wextra -Werror
LOCAL_SRC_FILES := keystore.cpp keyblob_utils.cpp
LOCAL_C_INCLUDES := external/openssl/include
-LOCAL_SHARED_LIBRARIES := libcutils libcrypto libhardware libkeystore_binder libutils liblog libbinder
+LOCAL_SHARED_LIBRARIES := \
+ libbinder \
+ libcutils \
+ libcrypto \
+ libhardware \
+ libkeystore_binder \
+ liblog \
+ libsoftkeymaster \
+ libutils
LOCAL_MODULE := keystore
LOCAL_MODULE_TAGS := optional
LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
diff --git a/keystore/include/keystore/keystore.h b/keystore/include/keystore/keystore.h
index 973c447..32354df 100644
--- a/keystore/include/keystore/keystore.h
+++ b/keystore/include/keystore/keystore.h
@@ -48,7 +48,8 @@
*/
enum {
KEYSTORE_FLAG_NONE = 0,
- KEYSTORE_FLAG_ENCRYPTED = 1,
+ KEYSTORE_FLAG_ENCRYPTED = 1 << 0,
+ KEYSTORE_FLAG_FALLBACK = 1 << 1,
};
/**
diff --git a/keystore/keyblob_utils.cpp b/keystore/keyblob_utils.cpp
index fd82d2a..b208073 100644
--- a/keystore/keyblob_utils.cpp
+++ b/keystore/keyblob_utils.cpp
@@ -26,9 +26,11 @@
*
* 4-byte SOFT_KEY_MAGIC
*
- * 4-byte 32-bit integer big endian for public_key_length
+ * 4-byte 32-bit integer big endian for public_key_length. This may be zero
+ * length which indicates the public key should be derived from the
+ * private key.
*
- * public_key_length bytes of public key
+ * public_key_length bytes of public key (may be empty)
*
* 4-byte 32-bit integer big endian for private_key_length
*
diff --git a/keystore/keystore.cpp b/keystore/keystore.cpp
index 12d3b44..b4cb64d 100644
--- a/keystore/keystore.cpp
+++ b/keystore/keystore.cpp
@@ -42,6 +42,8 @@
#include <hardware/keymaster.h>
+#include <keymaster/softkeymaster.h>
+
#include <utils/String8.h>
#include <utils/UniquePtr.h>
#include <utils/Vector.h>
@@ -471,6 +473,18 @@
}
}
+ bool isFallback() const {
+ return mBlob.flags & KEYSTORE_FLAG_FALLBACK;
+ }
+
+ void setFallback(bool fallback) {
+ if (fallback) {
+ mBlob.flags |= KEYSTORE_FLAG_FALLBACK;
+ } else {
+ mBlob.flags &= ~KEYSTORE_FLAG_FALLBACK;
+ }
+ }
+
void setVersion(uint8_t version) {
mBlob.version = version;
}
@@ -1004,6 +1018,23 @@
}
}
+ /*
+ * This will upgrade software-backed keys to hardware-backed keys when
+ * the HAL for the device supports the newer key types.
+ */
+ if (rc == NO_ERROR && type == TYPE_KEY_PAIR
+ && mDevice->common.module->module_api_version >= KEYMASTER_MODULE_API_VERSION_0_2
+ && keyBlob->isFallback()) {
+ ResponseCode imported = importKey(keyBlob->getValue(), keyBlob->getLength(), filename,
+ uid, keyBlob->isEncrypted() ? KEYSTORE_FLAG_ENCRYPTED : KEYSTORE_FLAG_NONE);
+
+ // The HAL allowed the import, reget the key to have the "fresh"
+ // version.
+ if (imported == NO_ERROR) {
+ rc = get(filename, keyBlob, TYPE_KEY_PAIR, uid);
+ }
+ }
+
if (type != TYPE_ANY && keyBlob->getType() != type) {
ALOGW("key found but type doesn't match: %d vs %d", keyBlob->getType(), type);
return KEY_NOT_FOUND;
@@ -1056,16 +1087,26 @@
return SYSTEM_ERROR;
}
+ bool isFallback = false;
rc = mDevice->import_keypair(mDevice, key, keyLen, &data, &dataLength);
if (rc) {
- ALOGE("Error while importing keypair: %d", rc);
- return SYSTEM_ERROR;
+ // If this is an old device HAL, try to fall back to an old version
+ if (mDevice->common.module->module_api_version < KEYMASTER_MODULE_API_VERSION_0_2) {
+ rc = openssl_import_keypair(mDevice, key, keyLen, &data, &dataLength);
+ isFallback = true;
+ }
+
+ if (rc) {
+ ALOGE("Error while importing keypair: %d", rc);
+ return SYSTEM_ERROR;
+ }
}
Blob keyBlob(data, dataLength, NULL, 0, TYPE_KEY_PAIR);
free(data);
keyBlob.setEncrypted(flags & KEYSTORE_FLAG_ENCRYPTED);
+ keyBlob.setFallback(isFallback);
return put(filename, &keyBlob, uid);
}
@@ -1688,6 +1729,7 @@
uint8_t* data;
size_t dataLength;
int rc;
+ bool isFallback = false;
const keymaster_device_t* device = mKeyStore->getDevice();
if (device == NULL) {
@@ -1698,7 +1740,7 @@
return ::SYSTEM_ERROR;
}
- if (keyType == EVP_PKEY_DSA && device->client_version >= 2) {
+ if (keyType == EVP_PKEY_DSA) {
keymaster_dsa_keygen_params_t dsa_params;
memset(&dsa_params, '\0', sizeof(dsa_params));
@@ -1734,8 +1776,13 @@
return ::SYSTEM_ERROR;
}
- rc = device->generate_keypair(device, TYPE_DSA, &dsa_params, &data, &dataLength);
- } else if (keyType == EVP_PKEY_EC && device->client_version >= 2) {
+ if (device->common.module->module_api_version >= KEYMASTER_MODULE_API_VERSION_0_2) {
+ rc = device->generate_keypair(device, TYPE_DSA, &dsa_params, &data, &dataLength);
+ } else {
+ isFallback = true;
+ rc = openssl_generate_keypair(device, TYPE_DSA, &dsa_params, &data, &dataLength);
+ }
+ } else if (keyType == EVP_PKEY_EC) {
keymaster_ec_keygen_params_t ec_params;
memset(&ec_params, '\0', sizeof(ec_params));
@@ -1747,7 +1794,12 @@
}
ec_params.field_size = keySize;
- rc = device->generate_keypair(device, TYPE_EC, &ec_params, &data, &dataLength);
+ if (device->common.module->module_api_version >= KEYMASTER_MODULE_API_VERSION_0_2) {
+ rc = device->generate_keypair(device, TYPE_EC, &ec_params, &data, &dataLength);
+ } else {
+ isFallback = true;
+ rc = openssl_generate_keypair(device, TYPE_EC, &ec_params, &data, &dataLength);
+ }
} else if (keyType == EVP_PKEY_RSA) {
keymaster_rsa_keygen_params_t rsa_params;
memset(&rsa_params, '\0', sizeof(rsa_params));
@@ -1799,6 +1851,8 @@
Blob keyBlob(data, dataLength, NULL, 0, TYPE_KEY_PAIR);
free(data);
+ keyBlob.setFallback(isFallback);
+
return mKeyStore->put(filename.string(), &keyBlob, callingUid);
}
@@ -1863,8 +1917,13 @@
params.digest_type = DIGEST_NONE;
params.padding_type = PADDING_NONE;
- rc = device->sign_data(device, ¶ms, keyBlob.getValue(), keyBlob.getLength(),
- data, length, out, outLength);
+ if (keyBlob.isFallback()) {
+ rc = openssl_sign_data(device, ¶ms, keyBlob.getValue(), keyBlob.getLength(), data,
+ length, out, outLength);
+ } else {
+ rc = device->sign_data(device, ¶ms, keyBlob.getValue(), keyBlob.getLength(), data,
+ length, out, outLength);
+ }
if (rc) {
ALOGW("device couldn't sign data");
return ::SYSTEM_ERROR;
@@ -1910,8 +1969,13 @@
params.digest_type = DIGEST_NONE;
params.padding_type = PADDING_NONE;
- rc = device->verify_data(device, ¶ms, keyBlob.getValue(), keyBlob.getLength(),
- data, dataLength, signature, signatureLength);
+ if (keyBlob.isFallback()) {
+ rc = openssl_verify_data(device, ¶ms, keyBlob.getValue(), keyBlob.getLength(), data,
+ dataLength, signature, signatureLength);
+ } else {
+ rc = device->verify_data(device, ¶ms, keyBlob.getValue(), keyBlob.getLength(), data,
+ dataLength, signature, signatureLength);
+ }
if (rc) {
return ::SYSTEM_ERROR;
} else {
@@ -1958,8 +2022,14 @@
return ::SYSTEM_ERROR;
}
- int rc = device->get_keypair_public(device, keyBlob.getValue(), keyBlob.getLength(), pubkey,
- pubkeyLength);
+ int rc;
+ if (keyBlob.isFallback()) {
+ rc = openssl_get_keypair_public(device, keyBlob.getValue(), keyBlob.getLength(), pubkey,
+ pubkeyLength);
+ } else {
+ rc = device->get_keypair_public(device, keyBlob.getValue(), keyBlob.getLength(), pubkey,
+ pubkeyLength);
+ }
if (rc) {
return ::SYSTEM_ERROR;
}
@@ -1997,7 +2067,7 @@
rc = ::SYSTEM_ERROR;
} else {
// A device doesn't have to implement delete_keypair.
- if (device->delete_keypair != NULL) {
+ if (device->delete_keypair != NULL && !keyBlob.isFallback()) {
if (device->delete_keypair(device, keyBlob.getValue(), keyBlob.getLength())) {
rc = ::SYSTEM_ERROR;
}
@@ -2210,7 +2280,7 @@
if (keyBlob.getType() == ::TYPE_KEY_PAIR) {
// A device doesn't have to implement delete_keypair.
- if (device->delete_keypair != NULL) {
+ if (device->delete_keypair != NULL && !keyBlob.isFallback()) {
if (device->delete_keypair(device, keyBlob.getValue(), keyBlob.getLength())) {
rc = ::SYSTEM_ERROR;
ALOGW("device couldn't remove %s", filename.string());
diff --git a/softkeymaster/Android.mk b/softkeymaster/Android.mk
index 8e19a93..0064d01 100644
--- a/softkeymaster/Android.mk
+++ b/softkeymaster/Android.mk
@@ -15,23 +15,27 @@
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
-
LOCAL_MODULE := keystore.default
-
LOCAL_MODULE_PATH := $(TARGET_OUT_SHARED_LIBRARIES)/hw
-
-LOCAL_SRC_FILES := keymaster_openssl.cpp
-
+LOCAL_SRC_FILES := module.cpp
LOCAL_C_INCLUDES := \
system/security/keystore \
external/openssl/include
-
-LOCAL_C_FLAGS = -fvisibility=hidden -Wall -Werror
-
-LOCAL_SHARED_LIBRARIES := libcrypto liblog libkeystore_binder
-
+LOCAL_CFLAGS = -fvisibility=hidden -Wall -Werror
+LOCAL_SHARED_LIBRARIES := libcrypto liblog libkeystore_binder libsoftkeymaster
LOCAL_MODULE_TAGS := optional
-
LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
+include $(BUILD_SHARED_LIBRARY)
+include $(CLEAR_VARS)
+LOCAL_MODULE := libsoftkeymaster
+LOCAL_SRC_FILES := keymaster_openssl.cpp
+LOCAL_C_INCLUDES := \
+ system/security/keystore \
+ external/openssl/include
+LOCAL_CFLAGS = -fvisibility=hidden -Wall -Werror
+LOCAL_SHARED_LIBRARIES := libcrypto liblog libkeystore_binder
+LOCAL_MODULE_TAGS := optional
+LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)/include
+LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
include $(BUILD_SHARED_LIBRARY)
diff --git a/softkeymaster/include/keymaster/softkeymaster.h b/softkeymaster/include/keymaster/softkeymaster.h
new file mode 100644
index 0000000..7d43099
--- /dev/null
+++ b/softkeymaster/include/keymaster/softkeymaster.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2013 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.
+ */
+
+#include <hardware/keymaster.h>
+
+#ifndef SOFTKEYMASTER_INCLUDE_KEYMASTER_SOFTKEYMASTER_H
+#define SOFTKEYMASTER_INCLUDE_KEYMASTER_SOFTKEYMASTER_H
+
+int openssl_generate_keypair(const keymaster_device_t* dev,
+ const keymaster_keypair_t key_type, const void* key_params,
+ uint8_t** keyBlob, size_t* keyBlobLength);
+
+int openssl_import_keypair(const keymaster_device_t* dev,
+ const uint8_t* key, const size_t key_length,
+ uint8_t** key_blob, size_t* key_blob_length);
+
+int openssl_get_keypair_public(const struct keymaster_device* dev,
+ const uint8_t* key_blob, const size_t key_blob_length,
+ uint8_t** x509_data, size_t* x509_data_length);
+
+int openssl_sign_data(const keymaster_device_t* dev,
+ const void* params,
+ const uint8_t* keyBlob, const size_t keyBlobLength,
+ const uint8_t* data, const size_t dataLength,
+ uint8_t** signedData, size_t* signedDataLength);
+
+int openssl_verify_data(const keymaster_device_t* dev,
+ const void* params,
+ const uint8_t* keyBlob, const size_t keyBlobLength,
+ const uint8_t* signedData, const size_t signedDataLength,
+ const uint8_t* signature, const size_t signatureLength);
+
+#endif /* SOFTKEYMASTER_INCLUDE_KEYMASTER_SOFTKEYMASTER_H */
diff --git a/softkeymaster/keymaster_openssl.cpp b/softkeymaster/keymaster_openssl.cpp
index 19ec999..4aaaea2 100644
--- a/softkeymaster/keymaster_openssl.cpp
+++ b/softkeymaster/keymaster_openssl.cpp
@@ -194,7 +194,6 @@
ALOGE("public key length encoding error: size=%ld, end=%d", publicLen, end - p);
return NULL;
}
- const uint8_t *pubKey = p;
p += publicLen;
if (end - p < 2) {
@@ -378,11 +377,10 @@
return 0;
}
-static int openssl_generate_keypair(const keymaster_device_t* dev,
+__attribute__ ((visibility ("default")))
+int openssl_generate_keypair(const keymaster_device_t*,
const keymaster_keypair_t key_type, const void* key_params,
uint8_t** keyBlob, size_t* keyBlobLength) {
- ssize_t privateLen, publicLen;
-
Unique_EVP_PKEY pkey(EVP_PKEY_new());
if (pkey.get() == NULL) {
logOpenSSLError("openssl_generate_keypair");
@@ -416,11 +414,10 @@
return 0;
}
-static int openssl_import_keypair(const keymaster_device_t* dev,
+__attribute__ ((visibility ("default")))
+int openssl_import_keypair(const keymaster_device_t*,
const uint8_t* key, const size_t key_length,
uint8_t** key_blob, size_t* key_blob_length) {
- int response = -1;
-
if (key == NULL) {
ALOGW("input key == NULL");
return -1;
@@ -450,7 +447,8 @@
return 0;
}
-static int openssl_get_keypair_public(const struct keymaster_device* dev,
+__attribute__ ((visibility ("default")))
+int openssl_get_keypair_public(const struct keymaster_device*,
const uint8_t* key_blob, const size_t key_blob_length,
uint8_t** x509_data, size_t* x509_data_length) {
@@ -588,16 +586,12 @@
return 0;
}
-static int openssl_sign_data(const keymaster_device_t* dev,
+__attribute__ ((visibility ("default")))
+int openssl_sign_data(const keymaster_device_t*,
const void* params,
const uint8_t* keyBlob, const size_t keyBlobLength,
const uint8_t* data, const size_t dataLength,
uint8_t** signedData, size_t* signedDataLength) {
-
- int result = -1;
- EVP_MD_CTX ctx;
- size_t maxSize;
-
if (data == NULL) {
ALOGW("input data to sign == NULL");
return -1;
@@ -711,7 +705,8 @@
return result == 0 ? 0 : -1;
}
-static int openssl_verify_data(const keymaster_device_t* dev,
+__attribute__ ((visibility ("default")))
+int openssl_verify_data(const keymaster_device_t*,
const void* params,
const uint8_t* keyBlob, const size_t keyBlobLength,
const uint8_t* signedData, const size_t signedDataLength,
@@ -728,7 +723,11 @@
}
int type = EVP_PKEY_type(pkey->type);
- if (type == EVP_PKEY_RSA) {
+ if (type == EVP_PKEY_DSA) {
+ keymaster_dsa_sign_params_t* sign_params = (keymaster_dsa_sign_params_t*) params;
+ return verify_dsa(pkey.get(), sign_params, signedData, signedDataLength, signature,
+ signatureLength);
+ } else if (type == EVP_PKEY_RSA) {
keymaster_rsa_sign_params_t* sign_params = (keymaster_rsa_sign_params_t*) params;
return verify_rsa(pkey.get(), sign_params, signedData, signedDataLength, signature,
signatureLength);
@@ -741,63 +740,3 @@
return -1;
}
}
-
-/* Close an opened OpenSSL instance */
-static int openssl_close(hw_device_t *dev) {
- delete dev;
- return 0;
-}
-
-/*
- * Generic device handling
- */
-static int openssl_open(const hw_module_t* module, const char* name,
- hw_device_t** device) {
- if (strcmp(name, KEYSTORE_KEYMASTER) != 0)
- return -EINVAL;
-
- Unique_keymaster_device_t dev(new keymaster_device_t);
- if (dev.get() == NULL)
- return -ENOMEM;
-
- dev->common.tag = HARDWARE_DEVICE_TAG;
- dev->common.version = 1;
- dev->common.module = (struct hw_module_t*) module;
- dev->common.close = openssl_close;
-
- dev->flags = KEYMASTER_SOFTWARE_ONLY;
-
- dev->generate_keypair = openssl_generate_keypair;
- dev->import_keypair = openssl_import_keypair;
- dev->get_keypair_public = openssl_get_keypair_public;
- dev->delete_keypair = NULL;
- dev->delete_all = NULL;
- dev->sign_data = openssl_sign_data;
- dev->verify_data = openssl_verify_data;
-
- ERR_load_crypto_strings();
- ERR_load_BIO_strings();
-
- *device = reinterpret_cast<hw_device_t*>(dev.release());
-
- return 0;
-}
-
-static struct hw_module_methods_t keystore_module_methods = {
- open: openssl_open,
-};
-
-struct keystore_module HAL_MODULE_INFO_SYM
-__attribute__ ((visibility ("default"))) = {
- common: {
- tag: HARDWARE_MODULE_TAG,
- version_major: 1,
- version_minor: 0,
- id: KEYSTORE_HARDWARE_MODULE_ID,
- name: "Keymaster OpenSSL HAL",
- author: "The Android Open Source Project",
- methods: &keystore_module_methods,
- dso: 0,
- reserved: {},
- },
-};
diff --git a/softkeymaster/module.cpp b/softkeymaster/module.cpp
new file mode 100644
index 0000000..758dfe7
--- /dev/null
+++ b/softkeymaster/module.cpp
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2012 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.
+ */
+#include <errno.h>
+#include <string.h>
+#include <stdint.h>
+
+#include <keymaster/softkeymaster.h>
+
+#include <keystore/keystore.h>
+
+#include <hardware/hardware.h>
+#include <hardware/keymaster.h>
+
+#include <openssl/err.h>
+
+#include <utils/UniquePtr.h>
+
+// For debugging
+//#define LOG_NDEBUG 0
+
+#define LOG_TAG "OpenSSLKeyMaster"
+#include <cutils/log.h>
+
+typedef UniquePtr<keymaster_device_t> Unique_keymaster_device_t;
+
+/* Close an opened OpenSSL instance */
+static int openssl_close(hw_device_t *dev) {
+ delete dev;
+ return 0;
+}
+
+/*
+ * Generic device handling
+ */
+static int openssl_open(const hw_module_t* module, const char* name,
+ hw_device_t** device) {
+ if (strcmp(name, KEYSTORE_KEYMASTER) != 0)
+ return -EINVAL;
+
+ Unique_keymaster_device_t dev(new keymaster_device_t);
+ if (dev.get() == NULL)
+ return -ENOMEM;
+
+ dev->common.tag = HARDWARE_DEVICE_TAG;
+ dev->common.version = 1;
+ dev->common.module = (struct hw_module_t*) module;
+ dev->common.close = openssl_close;
+
+ dev->flags = KEYMASTER_SOFTWARE_ONLY;
+
+ dev->generate_keypair = openssl_generate_keypair;
+ dev->import_keypair = openssl_import_keypair;
+ dev->get_keypair_public = openssl_get_keypair_public;
+ dev->delete_keypair = NULL;
+ dev->delete_all = NULL;
+ dev->sign_data = openssl_sign_data;
+ dev->verify_data = openssl_verify_data;
+
+ ERR_load_crypto_strings();
+ ERR_load_BIO_strings();
+
+ *device = reinterpret_cast<hw_device_t*>(dev.release());
+
+ return 0;
+}
+
+static struct hw_module_methods_t keystore_module_methods = {
+ open: openssl_open,
+};
+
+struct keystore_module HAL_MODULE_INFO_SYM
+__attribute__ ((visibility ("default"))) = {
+ common: {
+ tag: HARDWARE_MODULE_TAG,
+ module_api_version: KEYMASTER_MODULE_API_VERSION_0_2,
+ hal_api_version: HARDWARE_HAL_API_VERSION,
+ id: KEYSTORE_HARDWARE_MODULE_ID,
+ name: "Keymaster OpenSSL HAL",
+ author: "The Android Open Source Project",
+ methods: &keystore_module_methods,
+ dso: 0,
+ reserved: {},
+ },
+};