Split up main engine from methods
We need to add more methods to the keystore engine, so split out RSA so
it doesn't become too unwieldy.
This doesn't affect the size of the symbol table since the default
visibility for this module is "hidden."
Change-Id: I806553a8d1a01ff0ffd7b67054932ddf783bb502
diff --git a/keystore-engine/rsa_meth.cpp b/keystore-engine/rsa_meth.cpp
new file mode 100644
index 0000000..c1d643c
--- /dev/null
+++ b/keystore-engine/rsa_meth.cpp
@@ -0,0 +1,274 @@
+/*
+ * Copyright 2012 The Android Open Source Project
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <utils/UniquePtr.h>
+
+//#define LOG_NDEBUG 0
+#define LOG_TAG "OpenSSL-keystore-rsa"
+#include <cutils/log.h>
+
+#include <binder/IServiceManager.h>
+#include <keystore/IKeystoreService.h>
+
+#include <openssl/rsa.h>
+#include <openssl/engine.h>
+
+#include "methods.h"
+
+
+/*
+ * RSA ex_data index for keystore's key handle.
+ */
+static int rsa_key_handle;
+
+/*
+ * Only initialize the rsa_key_handle once.
+ */
+static pthread_once_t rsa_key_handle_control = PTHREAD_ONCE_INIT;
+
+struct RSA_Delete {
+ void operator()(RSA* p) const {
+ RSA_free(p);
+ }
+};
+typedef UniquePtr<RSA, RSA_Delete> Unique_RSA;
+
+
+using namespace android;
+
+/**
+ * Called to initialize RSA's ex_data for the key_id handle. This should
+ * only be called when protected by a lock.
+ */
+static void init_rsa_key_handle() {
+ rsa_key_handle = RSA_get_ex_new_index(0, NULL, keyhandle_new, keyhandle_dup,
+ keyhandle_free);
+}
+
+int keystore_rsa_priv_enc(int flen, const unsigned char* from, unsigned char* to, RSA* rsa,
+ int padding) {
+ ALOGV("keystore_rsa_priv_enc(%d, %p, %p, %p, %d)", flen, from, to, rsa, padding);
+
+ int num = RSA_size(rsa);
+ UniquePtr<uint8_t> padded(new uint8_t[num]);
+ if (padded.get() == NULL) {
+ ALOGE("could not allocate padded signature");
+ return 0;
+ }
+
+ switch (padding) {
+ case RSA_PKCS1_PADDING:
+ if (!RSA_padding_add_PKCS1_type_1(padded.get(), num, from, flen)) {
+ return 0;
+ }
+ break;
+ case RSA_X931_PADDING:
+ if (!RSA_padding_add_X931(padded.get(), num, from, flen)) {
+ return 0;
+ }
+ break;
+ case RSA_NO_PADDING:
+ if (!RSA_padding_add_none(padded.get(), num, from, flen)) {
+ return 0;
+ }
+ break;
+ default:
+ ALOGE("Unknown padding type: %d", padding);
+ return 0;
+ }
+
+ uint8_t* key_id = reinterpret_cast<uint8_t*>(RSA_get_ex_data(rsa, rsa_key_handle));
+ if (key_id == NULL) {
+ ALOGE("key had no key_id!");
+ return 0;
+ }
+
+ sp<IServiceManager> sm = defaultServiceManager();
+ sp<IBinder> binder = sm->getService(String16("android.security.keystore"));
+ sp<IKeystoreService> service = interface_cast<IKeystoreService>(binder);
+
+ if (service == NULL) {
+ ALOGE("could not contact keystore");
+ return 0;
+ }
+
+ uint8_t* reply = NULL;
+ size_t replyLen;
+ int32_t ret = service->sign(String16(reinterpret_cast<const char*>(key_id)), padded.get(),
+ num, &reply, &replyLen);
+ if (ret < 0) {
+ ALOGW("There was an error during signing: could not connect");
+ free(reply);
+ return 0;
+ } else if (ret != 0) {
+ ALOGW("Error during signing from keystore: %d", ret);
+ free(reply);
+ return 0;
+ } else if (replyLen <= 0) {
+ ALOGW("No valid signature returned");
+ return 0;
+ }
+
+ memcpy(to, reply, replyLen);
+ free(reply);
+
+ ALOGV("rsa=%p keystore_rsa_priv_enc => returning %p len %llu", rsa, to,
+ (unsigned long long) replyLen);
+ return static_cast<int>(replyLen);
+}
+
+int keystore_rsa_priv_dec(int flen, const unsigned char* from, unsigned char* to, RSA* rsa,
+ int padding) {
+ ALOGV("keystore_rsa_priv_dec(%d, %p, %p, %p, %d)", flen, from, to, rsa, padding);
+
+ uint8_t* key_id = reinterpret_cast<uint8_t*>(RSA_get_ex_data(rsa, rsa_key_handle));
+ if (key_id == NULL) {
+ ALOGE("key had no key_id!");
+ return 0;
+ }
+
+ sp<IServiceManager> sm = defaultServiceManager();
+ sp<IBinder> binder = sm->getService(String16("android.security.keystore"));
+ sp<IKeystoreService> service = interface_cast<IKeystoreService>(binder);
+
+ if (service == NULL) {
+ ALOGE("could not contact keystore");
+ return 0;
+ }
+
+ int num = RSA_size(rsa);
+
+ uint8_t* reply = NULL;
+ size_t replyLen;
+ int32_t ret = service->sign(String16(reinterpret_cast<const char*>(key_id)), from,
+ flen, &reply, &replyLen);
+ if (ret < 0) {
+ ALOGW("There was an error during rsa_mod_exp: could not connect");
+ return 0;
+ } else if (ret != 0) {
+ ALOGW("Error during sign from keystore: %d", ret);
+ return 0;
+ } else if (replyLen <= 0) {
+ ALOGW("No valid signature returned");
+ return 0;
+ }
+
+ /* Trim off the top zero if it's there */
+ uint8_t* alignedReply;
+ if (*reply == 0x00) {
+ alignedReply = reply + 1;
+ replyLen--;
+ } else {
+ alignedReply = reply;
+ }
+
+ int outSize;
+ switch (padding) {
+ case RSA_PKCS1_PADDING:
+ outSize = RSA_padding_check_PKCS1_type_2(to, num, alignedReply, replyLen, num);
+ break;
+ case RSA_X931_PADDING:
+ outSize = RSA_padding_check_X931(to, num, alignedReply, replyLen, num);
+ break;
+ case RSA_NO_PADDING:
+ outSize = RSA_padding_check_none(to, num, alignedReply, replyLen, num);
+ break;
+ default:
+ ALOGE("Unknown padding type: %d", padding);
+ outSize = -1;
+ break;
+ }
+
+ free(reply);
+
+ ALOGV("rsa=%p keystore_rsa_priv_dec => returning %p len %llu", rsa, to, outSize);
+ return outSize;
+}
+
+static RSA_METHOD keystore_rsa_meth = {
+ kKeystoreEngineId,
+ NULL, /* rsa_pub_enc (wrap) */
+ NULL, /* rsa_pub_dec (verification) */
+ keystore_rsa_priv_enc, /* rsa_priv_enc (signing) */
+ keystore_rsa_priv_dec, /* rsa_priv_dec (unwrap) */
+ NULL, /* rsa_mod_exp */
+ NULL, /* bn_mod_exp */
+ NULL, /* init */
+ NULL, /* finish */
+ RSA_FLAG_EXT_PKEY | RSA_FLAG_NO_BLINDING, /* flags */
+ NULL, /* app_data */
+ NULL, /* rsa_sign */
+ NULL, /* rsa_verify */
+ NULL, /* rsa_keygen */
+};
+
+static int register_rsa_methods() {
+ const RSA_METHOD* rsa_meth = RSA_PKCS1_SSLeay();
+
+ keystore_rsa_meth.rsa_pub_enc = rsa_meth->rsa_pub_enc;
+ keystore_rsa_meth.rsa_pub_dec = rsa_meth->rsa_pub_dec;
+ keystore_rsa_meth.rsa_mod_exp = rsa_meth->rsa_mod_exp;
+ keystore_rsa_meth.bn_mod_exp = rsa_meth->bn_mod_exp;
+
+ return 1;
+}
+
+int rsa_pkey_setup(ENGINE *e, EVP_PKEY *pkey, const char *key_id) {
+ Unique_RSA rsa(EVP_PKEY_get1_RSA(pkey));
+ if (!RSA_set_ex_data(rsa.get(), rsa_key_handle, reinterpret_cast<void*>(strdup(key_id)))) {
+ ALOGW("Could not set ex_data for loaded RSA key");
+ return 0;
+ }
+
+ RSA_set_method(rsa.get(), &keystore_rsa_meth);
+ RSA_blinding_off(rsa.get());
+
+ /*
+ * This should probably be an OpenSSL API, but EVP_PKEY_free calls
+ * ENGINE_finish(), so we need to call ENGINE_init() here.
+ */
+ ENGINE_init(e);
+ rsa->engine = e;
+ rsa->flags |= RSA_FLAG_EXT_PKEY;
+
+ return 1;
+}
+
+int rsa_register(ENGINE* e) {
+ if (!ENGINE_set_RSA(e, &keystore_rsa_meth)
+ || !register_rsa_methods()) {
+ ALOGE("Could not set up keystore RSA methods");
+ return 0;
+ }
+
+ /* We need a handle in the RSA keys as well for keygen if it's not already initialized. */
+ pthread_once(&rsa_key_handle_control, init_rsa_key_handle);
+ if (rsa_key_handle < 0) {
+ ALOGE("Could not set up RSA ex_data index");
+ return 0;
+ }
+
+ return 1;
+}