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.
(cherry picked from commit 17208e0de5a42722901d803118745cca25fd10c1)
Bug: 10600582
Change-Id: Ic02102cb2b7f66e2ad3469f4edd9d03c4ae3fdf4
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: {},
+ },
+};