--- /dev/null
+/*
+ * Copyright (c) 2015 Apple Inc. All Rights Reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+
+// Our Header
+#include <Security/SecureObjectSync/SOSBackupSliceKeyBag.h>
+
+
+// Needed headers for implementation
+#include "AssertMacros.h"
+#include <utilities/SecCFWrappers.h>
+#include <utilities/SecAKSWrappers.h>
+#include <utilities/SecBuffer.h>
+#include <utilities/SecCFError.h>
+#include <utilities/der_set.h>
+#include <utilities/der_plist_internal.h>
+#include <Security/SecRandom.h>
+#include <Security/SecureObjectSync/SOSPeerInfo.h>
+#include <Security/SecureObjectSync/SOSPeerInfoCollections.h>
+#include <Security/SecureObjectSync/SOSInternal.h>
+
+#include <corecrypto/ccec.h>
+#include <corecrypto/ccsha2.h>
+#include <corecrypto/ccrng.h>
+
+#include <limits.h>
+
+#include "SOSInternal.h"
+
+//
+// MARK: Type creation
+//
+
+CFGiblisFor(SOSBackupSliceKeyBag);
+
+const int kAKSBagSecretLength = 32;
+
+struct __OpaqueSOSBackupSliceKeyBag {
+ CFRuntimeBase _base;
+
+ CFDataRef aks_bag;
+
+ CFSetRef peers;
+ CFDictionaryRef wrapped_keys;
+};
+
+static void SOSBackupSliceKeyBagDestroy(CFTypeRef aObj) {
+ SOSBackupSliceKeyBagRef vb = (SOSBackupSliceKeyBagRef) aObj;
+
+ CFReleaseNull(vb->aks_bag);
+ CFReleaseNull(vb->peers);
+ CFReleaseNull(vb->wrapped_keys);
+}
+
+static CFStringRef SOSBackupSliceKeyBagCopyFormatDescription(CFTypeRef aObj, CFDictionaryRef formatOptions) {
+ SOSBackupSliceKeyBagRef vb = (SOSBackupSliceKeyBagRef) aObj;
+
+ CFMutableStringRef description = CFStringCreateMutable(kCFAllocatorDefault, 0);
+
+ CFStringAppendFormat(description, NULL, CFSTR("<SOSBackupSliceKeyBag@%p %ld"), vb, vb->peers ? CFSetGetCount(vb->peers) : 0);
+ CFStringAppend(description, CFSTR(">"));
+
+ return description;
+}
+
+
+//
+// MARK: Encode/Decode
+//
+
+const uint8_t* der_decode_BackupSliceKeyBag(CFAllocatorRef allocator,
+ SOSBackupSliceKeyBagRef* BackupSliceKeyBag, CFErrorRef *error,
+ const uint8_t* der, const uint8_t *der_end) {
+ if (der == NULL) return der;
+
+ const uint8_t *result = NULL;
+ SOSBackupSliceKeyBagRef vb = CFTypeAllocate(SOSBackupSliceKeyBag, struct __OpaqueSOSBackupSliceKeyBag, allocator);
+ require_quiet(SecAllocationError(vb, error, CFSTR("View bag allocation failed")), fail);
+
+ const uint8_t *sequence_end = NULL;
+ der = ccder_decode_sequence_tl(&sequence_end, der, der_end);
+ require_quiet(sequence_end == der_end, fail);
+
+ der = der_decode_data(kCFAllocatorDefault, kCFPropertyListImmutable, &vb->aks_bag, error, der, sequence_end);
+ vb->peers = SOSPeerInfoSetCreateFromArrayDER(kCFAllocatorDefault, &kSOSPeerSetCallbacks, error,
+ &der, der_end);
+ der = der_decode_dictionary(kCFAllocatorDefault, kCFPropertyListImmutable, &vb->wrapped_keys, error, der, sequence_end);
+
+ require_quiet(SecRequirementError(der == der_end, error, CFSTR("Extra space in sequence")), fail);
+
+ if (BackupSliceKeyBag)
+ CFTransferRetained(*BackupSliceKeyBag, vb);
+
+ result = der;
+
+fail:
+ CFReleaseNull(vb);
+ return result;
+}
+
+size_t der_sizeof_BackupSliceKeyBag(SOSBackupSliceKeyBagRef BackupSliceKeyBag, CFErrorRef *error) {
+ size_t result = 0;
+
+ size_t bag_size = der_sizeof_data(BackupSliceKeyBag->aks_bag, error);
+ require_quiet(bag_size, fail);
+
+ size_t peers_size = SOSPeerInfoSetGetDEREncodedArraySize(BackupSliceKeyBag->peers, error);
+ require_quiet(peers_size, fail);
+
+ size_t wrapped_keys_size = der_sizeof_dictionary(BackupSliceKeyBag->wrapped_keys, error);
+ require_quiet(wrapped_keys_size, fail);
+
+ result = ccder_sizeof(CCDER_CONSTRUCTED_SEQUENCE, bag_size + peers_size + wrapped_keys_size);
+
+fail:
+ return result;
+}
+
+uint8_t* der_encode_BackupSliceKeyBag(SOSBackupSliceKeyBagRef set, CFErrorRef *error,
+ const uint8_t *der, uint8_t *der_end) {
+ uint8_t *result = NULL;
+ if (der_end == NULL) return der_end;
+
+ require_quiet(SecRequirementError(set != NULL, error, CFSTR("Null set passed to encode")), fail);
+
+ der_end = ccder_encode_constructed_tl(CCDER_CONSTRUCTED_SEQUENCE, der_end, der,
+ der_encode_data(set->aks_bag, error, der,
+ SOSPeerInfoSetEncodeToArrayDER(set->peers, error, der,
+ der_encode_dictionary(set->wrapped_keys, error, der, der_end))));
+
+ require_quiet(der_end == der, fail);
+
+ result = der_end;
+fail:
+ return result;
+}
+
+
+SOSBackupSliceKeyBagRef SOSBackupSliceKeyBagCreateFromData(CFAllocatorRef allocator, CFDataRef data, CFErrorRef *error) {
+ SOSBackupSliceKeyBagRef result = NULL;
+ SOSBackupSliceKeyBagRef decodedBag = NULL;
+
+ const uint8_t *der = CFDataGetBytePtr(data);
+ const uint8_t *der_end = der + CFDataGetLength(data);
+
+ der = der_decode_BackupSliceKeyBag(allocator, &decodedBag, error, der, der_end);
+
+ require_quiet(SecRequirementError(der == der_end, error, CFSTR("Didn't consume all data supplied")), fail);
+
+ CFTransferRetained(result, decodedBag);
+
+fail:
+ CFReleaseNull(decodedBag);
+ return result;
+}
+
+//
+// MARK: Construction
+//
+
+bool SOSBSKBIsGoodBackupPublic(CFDataRef publicKey, CFErrorRef *error) {
+ bool result = false;
+
+ ccec_pub_ctx_decl_cp(SOSGetBackupKeyCurveParameters(), pub_key);
+
+ int cc_result = ccec_compact_import_pub(SOSGetBackupKeyCurveParameters(), CFDataGetLength(publicKey), CFDataGetBytePtr(publicKey), pub_key);
+
+ require_action_quiet(cc_result == 0, exit, SOSErrorCreate(kSOSErrorDecodeFailure, error, NULL, CFSTR("Unable to decode public key: %@"), publicKey));
+
+ result = true;
+exit:
+ return result;
+
+}
+
+
+static CFDataRef SOSCopyECWrapped(CFDataRef publicKey, CFDataRef secret, CFErrorRef *error) {
+ CFDataRef result = NULL;
+
+ ccec_pub_ctx_decl_cp(SOSGetBackupKeyCurveParameters(), pub_key);
+
+ int cc_result = ccec_compact_import_pub(SOSGetBackupKeyCurveParameters(), CFDataGetLength(publicKey), CFDataGetBytePtr(publicKey), pub_key);
+
+ require_action_quiet(cc_result == 0, exit, SOSErrorCreate(kSOSErrorDecodeFailure, error, NULL, CFSTR("Unable to decode public key: %@"), publicKey));
+
+ result = SOSCopyECWrappedData(pub_key, secret, error);
+
+exit:
+ return result;
+}
+
+
+static CFDictionaryRef SOSBackupSliceKeyBagCopyWrappedKeys(SOSBackupSliceKeyBagRef vb, CFDataRef secret, CFErrorRef *error) {
+ CFDictionaryRef result = NULL;
+ CFMutableDictionaryRef wrappedKeys = CFDictionaryCreateMutableForCFTypes(kCFAllocatorDefault);
+
+ __block bool success = true;
+ CFSetForEach(vb->peers, ^(const void *value) {
+ SOSPeerInfoRef pi = (SOSPeerInfoRef) value;
+ if (isSOSPeerInfo(pi)) {
+ CFStringRef id = SOSPeerInfoGetPeerID(pi);
+ CFDataRef backupKey = SOSPeerInfoCopyBackupKey(pi);
+
+ if (backupKey) {
+ CFDataRef wrappedKey = SOSCopyECWrapped(backupKey, secret, error);
+ if (wrappedKey) {
+ CFDictionaryAddValue(wrappedKeys, id, wrappedKey);
+ } else {
+ success = false;
+ }
+ CFReleaseNull(wrappedKey);
+ CFReleaseNull(backupKey);
+ }
+
+ }
+ });
+
+ if (success)
+ CFTransferRetained(result, wrappedKeys);
+
+ CFReleaseNull(wrappedKeys);
+ return result;
+}
+
+static bool SOSBackupSliceKeyBagCreateBackupBag(SOSBackupSliceKeyBagRef vb, CFErrorRef* error) {
+ CFReleaseNull(vb->aks_bag);
+
+ // Choose a random key.
+ PerformWithBufferAndClear(kAKSBagSecretLength, ^(size_t size, uint8_t *buffer) {
+ SecRandomCopyBytes(kSecRandomDefault, size, buffer);
+ CFDataRef secret = CFDataCreateWithBytesNoCopy(kCFAllocatorDefault, buffer, size, kCFAllocatorNull);
+
+ CFAssignRetained(vb->wrapped_keys, SOSBackupSliceKeyBagCopyWrappedKeys(vb, secret, error));
+ CFAssignRetained(vb->aks_bag, SecAKSCopyBackupBagWithSecret(size, buffer, error));
+
+ CFReleaseSafe(secret);
+ });
+
+ return vb->aks_bag != NULL;
+}
+
+
+CFDataRef SOSBSKBCopyEncoded(SOSBackupSliceKeyBagRef BackupSliceKeyBag, CFErrorRef* error) {
+ CFDataRef result = NULL;
+ CFMutableDataRef encoded = NULL;
+
+ size_t encodedSize = der_sizeof_BackupSliceKeyBag(BackupSliceKeyBag, error);
+ require_quiet(encodedSize, fail);
+
+ encoded = CFDataCreateMutableWithScratch(kCFAllocatorDefault, encodedSize);
+ require_quiet(SecAllocationError(encoded, error, CFSTR("Faild to create scratch")), fail);
+
+ uint8_t *encode_to = CFDataGetMutableBytePtr(encoded);
+ uint8_t *encode_to_end = encode_to + CFDataGetLength(encoded);
+ require_quiet(encode_to == der_encode_BackupSliceKeyBag(BackupSliceKeyBag, error, encode_to, encode_to_end), fail);
+
+ CFTransferRetained(result, encoded);
+
+fail:
+ CFReleaseSafe(encoded);
+ return result;
+}
+
+static CFSetRef SOSBackupSliceKeyBagCreatePeerSet(CFAllocatorRef allocator, CFSetRef peers) {
+ CFMutableSetRef result = CFSetCreateMutableForSOSPeerInfosByID(allocator);
+
+ CFSetForEach(peers, ^(const void *value) {
+ CFSetAddValue(result, value);
+ });
+
+ return result;
+}
+
+SOSBackupSliceKeyBagRef SOSBackupSliceKeyBagCreate(CFAllocatorRef allocator, CFSetRef peers, CFErrorRef* error) {
+ SOSBackupSliceKeyBagRef result = NULL;
+ SOSBackupSliceKeyBagRef vb = CFTypeAllocate(SOSBackupSliceKeyBag, struct __OpaqueSOSBackupSliceKeyBag, allocator);
+ require_quiet(SecAllocationError(vb, error, CFSTR("View bag allocation failed")), fail);
+
+ require_quiet(SecRequirementError(CFSetGetCount(peers) > 0, error, CFSTR("Need peers")), fail);
+
+ vb->peers = SOSBackupSliceKeyBagCreatePeerSet(allocator, peers);
+ vb->wrapped_keys = CFDictionaryCreateMutableForCFTypes(allocator);
+
+ require_quiet(SOSBackupSliceKeyBagCreateBackupBag(vb, error), fail);
+
+ CFTransferRetained(result, vb);
+
+fail:
+ CFReleaseNull(vb);
+ return result;
+}
+
+SOSBackupSliceKeyBagRef SOSBackupSliceKeyBagCreateDirect(CFAllocatorRef allocator, CFDataRef aks_bag, CFErrorRef *error)
+{
+ SOSBackupSliceKeyBagRef result = NULL;
+ SOSBackupSliceKeyBagRef vb = CFTypeAllocate(SOSBackupSliceKeyBag, struct __OpaqueSOSBackupSliceKeyBag, allocator);
+ require_quiet(SecAllocationError(vb, error, CFSTR("View bag allocation failed")), fail);
+
+ require_quiet(SecRequirementError(aks_bag, error, CFSTR("Need aks bag")), fail);
+
+ vb->aks_bag = CFRetainSafe(aks_bag);
+ vb->peers = CFSetCreateMutableForSOSPeerInfosByID(allocator);
+ vb->wrapped_keys = CFDictionaryCreateMutableForCFTypes(allocator);
+
+ CFTransferRetained(result, vb);
+
+fail:
+ CFReleaseNull(vb);
+ return result;
+}
+
+//
+// MARK: Use
+//
+
+bool SOSBSKBIsDirect(SOSBackupSliceKeyBagRef backupSliceKeyBag)
+{
+ return 0 == CFSetGetCount(backupSliceKeyBag->peers);
+}
+
+CFDataRef SOSBSKBCopyAKSBag(SOSBackupSliceKeyBagRef backupSliceKeyBag, CFErrorRef* error)
+{
+ return CFRetainSafe(backupSliceKeyBag->aks_bag);
+}
+
+CFSetRef SOSBSKBGetPeers(SOSBackupSliceKeyBagRef backupSliceKeyBag){
+ return backupSliceKeyBag->peers;
+}
+
+static keybag_handle_t SOSBSKBLoadAndUnlockBagWithSecret(SOSBackupSliceKeyBagRef backupSliceKeyBag,
+ size_t secretSize, const uint8_t *secret,
+ CFErrorRef *error)
+{
+#if !TARGET_HAS_KEYSTORE
+ return bad_keybag_handle;
+#else
+ keybag_handle_t result = bad_keybag_handle;
+ keybag_handle_t bag_handle = bad_keybag_handle;
+
+ require_quiet(SecRequirementError(backupSliceKeyBag->aks_bag, error,
+ CFSTR("No aks bag to load")), exit);
+ require_quiet(SecRequirementError(CFDataGetLength(backupSliceKeyBag->aks_bag) < INT_MAX, error,
+ CFSTR("No aks bag to load")), exit);
+ require_quiet(SecRequirementError(secretSize <= INT_MAX, error,
+ CFSTR("secret too big")), exit);
+
+ kern_return_t aks_result;
+ aks_result = aks_load_bag(CFDataGetBytePtr(backupSliceKeyBag->aks_bag),
+ (int) CFDataGetLength(backupSliceKeyBag->aks_bag),
+ &bag_handle);
+ require_quiet(SecKernError(aks_result, error,
+ CFSTR("aks_load_bag failed: %d"), aks_result), exit);
+
+ aks_result = aks_unlock_bag(bag_handle, secret, (int) secretSize);
+ require_quiet(SecKernError(aks_result, error,
+ CFSTR("failed to unlock bag: %d"), aks_result), exit);
+
+ result = bag_handle;
+ bag_handle = bad_keybag_handle;
+
+exit:
+ if (bag_handle != bad_keybag_handle) {
+ (void) aks_unload_bag(bag_handle);
+ }
+
+ return result;
+#endif
+}
+
+keybag_handle_t SOSBSKBLoadAndUnlockWithPeerIDAndSecret(SOSBackupSliceKeyBagRef backupSliceKeyBag,
+ CFStringRef peerID, CFDataRef peerSecret,
+ CFErrorRef *error)
+{
+ __block keybag_handle_t result = bad_keybag_handle;
+
+ CFDataRef lookedUpData = CFDictionaryGetValue(backupSliceKeyBag->wrapped_keys, peerID);
+ require_quiet(SecRequirementError(lookedUpData != NULL, error, CFSTR("%@ has no wrapped key in %@"), peerID, backupSliceKeyBag), exit);
+
+ require_quiet(SOSPerformWithDeviceBackupFullKey(SOSGetBackupKeyCurveParameters(), peerSecret, error, ^(ccec_full_ctx_t fullKey) {
+ SOSPerformWithUnwrappedData(fullKey, lookedUpData, error, ^(size_t size, uint8_t *buffer) {
+ result = SOSBSKBLoadAndUnlockBagWithSecret(backupSliceKeyBag, size, buffer, error);
+ });
+ }), exit);
+
+exit:
+ return result;
+}
+
+
+keybag_handle_t SOSBSKBLoadAndUnlockWithPeerSecret(SOSBackupSliceKeyBagRef backupSliceKeyBag,
+ SOSPeerInfoRef peer, CFDataRef peerSecret,
+ CFErrorRef *error)
+{
+ return SOSBSKBLoadAndUnlockWithPeerIDAndSecret(backupSliceKeyBag, SOSPeerInfoGetPeerID(peer), peerSecret, error);
+}
+
+keybag_handle_t SOSBSKBLoadAndUnlockWithDirectSecret(SOSBackupSliceKeyBagRef backupSliceKeyBag,
+ CFDataRef secret,
+ CFErrorRef *error)
+{
+ keybag_handle_t result = bad_keybag_handle;
+ require_quiet(SecRequirementError(SOSBSKBIsDirect(backupSliceKeyBag), error, CFSTR("Not direct bag")), exit);
+
+ result = SOSBSKBLoadAndUnlockBagWithSecret(backupSliceKeyBag,
+ CFDataGetLength(secret),
+ CFDataGetBytePtr(secret),
+ error);
+
+exit:
+ return result;
+}
projects / apple / security.git / blobdiff