SecDbKeychainItem.m   [plain text]

/*
* Copyright (c) 2006-2014 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@
*/

/*
* SecDbKeychainItem.c - CoreFoundation-based constants and functions for
access to Security items (certificates, keys, identities, and
passwords.)
*/

#include "keychain/securityd/SecDbKeychainItem.h"

#import "SecInternalReleasePriv.h"
#include "keychain/securityd/SecItemSchema.h"
#include "keychain/securityd/SecItemServer.h"
#include "keychain/securityd/SecItemDb.h"
#include <CommonCrypto/CommonCryptor.h>
#include <CommonCrypto/CommonCryptorSPI.h>
#include <Security/SecBasePriv.h>
#include <Security/SecItem.h>
#include <Security/SecItemPriv.h>
#include <Security/SecItemInternal.h>
#include <Security/SecRandom.h>
#include <Security/SecAccessControl.h>
#include <Security/SecAccessControlPriv.h>
#include <utilities/der_plist.h>
#include <utilities/der_plist_internal.h>
#include <utilities/SecCFCCWrappers.h>
#import "SecDbKeychainItemV7.h"
#import "SecDbKeychainMetadataKeyStore.h"
#import "sec_action.h"

#if USE_KEYSTORE
#include <LocalAuthentication/LAPublicDefines.h>
#include <LocalAuthentication/LAPrivateDefines.h>
#include <coreauthd_spi.h>
#include <libaks_acl_cf_keys.h>
#include "keychain/securityd/spi.h"

#endif /* USE_KEYSTORE */

#include "OSX/utilities/SecAKSWrappers.h"

pthread_key_t CURRENT_CONNECTION_KEY;

// From SecItemServer, should be a acl-check block
bool itemInAccessGroup(CFDictionaryRef item, CFArrayRef accessGroups);

static keyclass_t kc_parse_keyclass(CFTypeRef value, CFErrorRef *error);
static CFTypeRef kc_encode_keyclass(keyclass_t keyclass);
static CFDataRef kc_copy_protection_data(SecAccessControlRef access_control);
static CFTypeRef kc_copy_protection_from(const uint8_t *der, const uint8_t *der_end);
static CF_RETURNS_RETAINED CFMutableDictionaryRef s3dl_item_v2_decode(CFDataRef plain, CFErrorRef *error);
static CF_RETURNS_RETAINED CFMutableDictionaryRef s3dl_item_v3_decode(CFDataRef plain, CFErrorRef *error);
#if USE_KEYSTORE && !TARGET_OS_SIMULATOR
static bool kc_attribs_key_encrypted_data_from_blob(keybag_handle_t keybag, const SecDbClass *class, const void *blob_data, size_t blob_data_len, SecAccessControlRef access_control, uint32_t version,
CFMutableDictionaryRef *authenticated_attributes, aks_ref_key_t *ref_key, CFDataRef *encrypted_data, CFErrorRef *error);
static CFDataRef kc_create_auth_data(SecAccessControlRef access_control, CFDictionaryRef auth_attributes);
static CFDataRef kc_copy_access_groups_data(CFArrayRef access_groups, CFErrorRef *error);
#endif

static const uint8_t* der_decode_plist_with_repair(CFAllocatorRef pl, CFOptionFlags mutability, CFPropertyListRef* cf, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef allocator, CFOptionFlags mutability, CFPropertyListRef* pl, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end));
static const uint8_t* der_decode_dictionary_with_repair(CFAllocatorRef allocator, CFOptionFlags mutability, CFDictionaryRef* dictionary, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef allocator, CFOptionFlags mutability, CFPropertyListRef* pl, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end));
static const uint8_t* der_decode_key_value_with_repair(CFAllocatorRef allocator, CFOptionFlags mutability, CFPropertyListRef* key, CFPropertyListRef* value, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef allocator, CFOptionFlags mutability, CFPropertyListRef* pl, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end));
static const uint8_t* der_decode_array_with_repair(CFAllocatorRef allocator, CFOptionFlags mutability, CFArrayRef* array, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef allocator, CFOptionFlags mutability, CFPropertyListRef* pl, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end));
static const uint8_t* der_decode_set_with_repair(CFAllocatorRef allocator, CFOptionFlags mutability, CFSetRef* set, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef allocator, CFOptionFlags mutability, CFPropertyListRef* pl, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end));

const uint32_t kUseDefaultIVMask = 1<<31;
const int16_t kIVSizeAESGCM = 12;

// echo "keychainblobstaticiv" | openssl dgst -sha256 | cut -c1-24 | xargs -I {} echo "0x{}" | xxd -r | xxd -p -i
static const uint8_t gcmIV[kIVSizeAESGCM] = {
0x1e, 0xa0, 0x5c, 0xa9, 0x98, 0x2e, 0x87, 0xdc, 0xf1, 0x45, 0xe8, 0x24
};

/* Given plainText create and return a CFDataRef containing:
BULK_KEY = RandomKey()
version || keyclass|ACL || KeyStore_WRAP(keyclass, BULK_KEY) ||
AES(BULK_KEY, NULL_IV, plainText || padding)
*/
bool ks_encrypt_data_legacy(keybag_handle_t keybag, SecAccessControlRef access_control, CFDataRef acm_context,
CFDictionaryRef attributes, CFDictionaryRef authenticated_attributes, CFDataRef *pBlob, bool useDefaultIV, CFErrorRef *error) {
CFMutableDataRef blob = NULL;
CFDataRef ac_data = NULL;
bool ok = true;
//check(keybag >= 0);

/* Precalculate output blob length. */
const uint32_t bulkKeySize = 32; /* Use 256 bit AES key for bulkKey. */
const uint32_t maxKeyWrapOverHead = 8 + 32;
uint8_t bulkKey[bulkKeySize];
CFMutableDataRef bulkKeyWrapped = CFDataCreateMutable(NULL, 0);
CFDataSetLength(bulkKeyWrapped, bulkKeySize + maxKeyWrapOverHead);
uint32_t key_wrapped_size;
size_t ivLen = 0;
const uint8_t *iv = NULL;
const uint8_t *aad = NULL; // Additional Authenticated Data
ptrdiff_t aadLen = 0;

#if USE_KEYSTORE
CFDataRef auth_data = NULL;
#endif

/* If access_control specifies only protection and no ACL, use legacy blob format version 3,
which has better support for sync/backup. Otherwise, force new format v6 unless useDefaultIV is set. */
bool hasACLConstraints = SecAccessControlGetConstraints(access_control);
const uint32_t version = (hasACLConstraints ? 6 : 3);
CFDataRef plainText = NULL;
if (version < 4) {
CFMutableDictionaryRef attributes_dict = CFDictionaryCreateMutableCopy(NULL, 0, attributes);
if (authenticated_attributes) {
CFDictionaryForEach(authenticated_attributes, ^(const void *key, const void *value) {
CFDictionaryAddValue(attributes_dict, key, value);
});
}

if (attributes_dict) {
// Drop the accc attribute for non v6 items during encode.
CFDictionaryRemoveValue(attributes_dict, kSecAttrAccessControl);
plainText = CFPropertyListCreateDERData(kCFAllocatorDefault, attributes_dict, error);
CFRelease(attributes_dict);
}
} else {
#if USE_KEYSTORE && !TARGET_OS_SIMULATOR
if (attributes) {
plainText = CFPropertyListCreateDERData(kCFAllocatorDefault, attributes, error);
}
#else
CFMutableDictionaryRef attributes_dict = CFDictionaryCreateMutableCopy(NULL, 0, attributes);
if (authenticated_attributes) {
CFDictionaryForEach(authenticated_attributes, ^(const void *key, const void *value) {
CFDictionaryAddValue(attributes_dict, key, value);
});
}

if (attributes_dict) {
plainText = CFPropertyListCreateDERData(kCFAllocatorDefault, attributes_dict, error);
CFRelease(attributes_dict);
}
#endif
}

if (!plainText || CFGetTypeID(plainText) != CFDataGetTypeID()
|| access_control == 0) {
ok = SecError(errSecParam, error, CFSTR("ks_encrypt_data: invalid plain text"));
goto out;
}

size_t ptLen = CFDataGetLength(plainText);
size_t ctLen = ptLen;
size_t tagLen = 16;
keyclass_t actual_class = 0;

if (SecRandomCopyBytes(kSecRandomDefault, bulkKeySize, bulkKey)) {
ok = SecError(errSecAllocate, error, CFSTR("ks_encrypt_data: SecRandomCopyBytes failed"));
goto out;
}

/* Extract keyclass from access control. */
keyclass_t keyclass = kc_parse_keyclass(SecAccessControlGetProtection(access_control), error);
if (!keyclass)
goto out;

#if USE_KEYSTORE && !TARGET_OS_SIMULATOR
if (version >= 4) {
auth_data = kc_create_auth_data(access_control, authenticated_attributes);
require_quiet(ok = ks_encrypt_acl(keybag, keyclass, bulkKeySize, bulkKey, bulkKeyWrapped, auth_data, acm_context, access_control, error), out);
} else
#endif
{
/* Encrypt bulkKey. */
require_quiet(ok = ks_crypt(kAKSKeyOpEncrypt, keybag,
keyclass, bulkKeySize, bulkKey,
&actual_class, bulkKeyWrapped,
error), out);
}

key_wrapped_size = (uint32_t)CFDataGetLength(bulkKeyWrapped);
UInt8 *cursor;
size_t blobLen = sizeof(version);
uint32_t prot_length = 0;

if (!hasACLConstraints) {
blobLen += sizeof(actual_class);
} else {
require_quiet(ac_data = kc_copy_protection_data(access_control), out);
prot_length = (uint32_t)CFDataGetLength(ac_data);
blobLen += sizeof(prot_length) + prot_length;
}

blobLen += sizeof(key_wrapped_size) + key_wrapped_size + ctLen + tagLen;
require_quiet(blob = CFDataCreateMutable(NULL, blobLen), out);
CFDataSetLength(blob, blobLen);
cursor = CFDataGetMutableBytePtr(blob);

*((uint32_t *)cursor) = useDefaultIV ? (version | kUseDefaultIVMask) : version;
cursor += sizeof(version);

//secerror("class: %d actual class: %d", keyclass, actual_class);
if (!hasACLConstraints) {
*((keyclass_t *)cursor) = actual_class;
cursor += sizeof(keyclass);
} else {
*((uint32_t *)cursor) = prot_length;
cursor += sizeof(prot_length);

CFDataGetBytes(ac_data, CFRangeMake(0, prot_length), cursor);
cursor += prot_length;
}

*((uint32_t *)cursor) = key_wrapped_size;
cursor += sizeof(key_wrapped_size);

if (useDefaultIV) {
iv = gcmIV;
ivLen = kIVSizeAESGCM;
// AAD is (version || ac_data || key_wrapped_size)
aad = CFDataGetMutableBytePtr(blob);
aadLen = cursor - aad;
}

memcpy(cursor, CFDataGetBytePtr(bulkKeyWrapped), key_wrapped_size);
cursor += key_wrapped_size;

/* Encrypt the plainText with the bulkKey. */
CCCryptorStatus ccerr = CCCryptorGCM(kCCEncrypt, kCCAlgorithmAES128,
bulkKey, bulkKeySize,
iv, ivLen, /* iv */
aad, aadLen, /* auth data */
CFDataGetBytePtr(plainText), ptLen,
cursor,
cursor + ctLen, &tagLen);
if (ccerr) {
ok = SecError(errSecInternal, error, CFSTR("ks_encrypt_data: CCCryptorGCM failed: %d"), ccerr);
goto out;
}
if (tagLen != 16) {
ok = SecError(errSecInternal, error, CFSTR("ks_encrypt_data: CCCryptorGCM expected: 16 got: %ld byte tag"), tagLen);
goto out;
}

out:
memset(bulkKey, 0, sizeof(bulkKey));
CFReleaseSafe(ac_data);
CFReleaseSafe(bulkKeyWrapped);
CFReleaseSafe(plainText);
if (!ok) {
CFReleaseSafe(blob);
} else {
*pBlob = blob;
}

#if USE_KEYSTORE
CFReleaseSafe(auth_data);
#endif
return ok;
}

static void
ks_warn_non_device_keybag(void)
{
static dispatch_once_t once;
static sec_action_t action;

dispatch_once(&once, ^{
action = sec_action_create("non-device keybag", 2);
sec_action_set_handler(action, ^{
secwarning("ks_encrypt_data: called with non-device keybag - call should be rerouted to ks_encrypt_data_legacy");
});
});
sec_action_perform(action);
}

bool ks_encrypt_data(keybag_handle_t keybag, SecAccessControlRef access_control, CFDataRef acm_context,
CFDictionaryRef secretData, CFDictionaryRef attributes, CFDictionaryRef authenticated_attributes, CFDataRef *pBlob, bool useDefaultIV, CFErrorRef *error) {
return ks_encrypt_data_with_backupuuid(keybag, access_control, acm_context, secretData, attributes, authenticated_attributes, pBlob, NULL, useDefaultIV, error);
}

bool ks_encrypt_data_with_backupuuid(keybag_handle_t keybag, SecAccessControlRef access_control, CFDataRef acm_context,
CFDictionaryRef secretData, CFDictionaryRef attributes, CFDictionaryRef authenticated_attributes, CFDataRef *pBlob, CFDataRef *bkUUID, bool useDefaultIV, CFErrorRef *error) {
if (keybag != KEYBAG_DEVICE) {
ks_warn_non_device_keybag();

CFMutableDictionaryRef allAttributes = CFDictionaryCreateMutableCopy(NULL, CFDictionaryGetCount(secretData) + CFDictionaryGetCount(attributes), attributes);
CFDictionaryForEach(secretData, ^(const void *key, const void *value) {
CFDictionaryAddValue(allAttributes, key, value);
});
bool result = ks_encrypt_data_legacy(keybag, access_control, acm_context, allAttributes, authenticated_attributes, pBlob, useDefaultIV, error);
CFReleaseNull(allAttributes);
return result;
}

keyclass_t key_class = kc_parse_keyclass(SecAccessControlGetProtection(access_control), error);
if (!key_class) {
return false;
}

if (SecAccessControlGetConstraints(access_control)) {
NSMutableDictionary* allAttributes = [(__bridge NSDictionary*)attributes mutableCopy];
[allAttributes addEntriesFromDictionary:(__bridge NSDictionary*)secretData];
return ks_encrypt_data_legacy(keybag, access_control, acm_context, (__bridge CFDictionaryRef)allAttributes, authenticated_attributes, pBlob, useDefaultIV, error);
}

bool success = false;
@autoreleasepool {
NSMutableDictionary* metadataAttributes = attributes ? [(__bridge NSDictionary*)attributes mutableCopy] : [NSMutableDictionary dictionary];
[metadataAttributes addEntriesFromDictionary:(__bridge NSDictionary*)authenticated_attributes];
metadataAttributes[@"SecAccessControl"] = (__bridge_transfer NSData*)SecAccessControlCopyData(access_control);

NSString* tamperCheck = [[NSUUID UUID] UUIDString]; // can use the item persistent reference when that starts getting filled in
SecDbKeychainItemV7* item = [[SecDbKeychainItemV7 alloc] initWithSecretAttributes:(__bridge NSDictionary*)secretData metadataAttributes:metadataAttributes tamperCheck:tamperCheck keyclass:key_class];

NSError* localError = nil;
NSData* encryptedBlob = [item encryptedBlobWithKeybag:keybag accessControl:access_control acmContext:(__bridge NSData*)acm_context error:&localError];
if (encryptedBlob) {
NSMutableData* encryptedBlobWithVersion = [NSMutableData dataWithLength:encryptedBlob.length + sizeof(uint32_t)];
*((uint32_t*)encryptedBlobWithVersion.mutableBytes) = (uint32_t)7;
memcpy((uint32_t*)encryptedBlobWithVersion.mutableBytes + 1, encryptedBlob.bytes, encryptedBlob.length);
*pBlob = (__bridge_retained CFDataRef)encryptedBlobWithVersion;
if (bkUUID && item.backupUUID) { // TODO: Failing this should turn into at least a stern warning at some point
*bkUUID = (__bridge_retained CFDataRef)[item.backupUUID copy];
}
success = true;
}
else {
if (error) {
*error = (__bridge_retained CFErrorRef)localError;
}
}
}

return success;
}

/* Given cipherText containing:
version || keyclass || KeyStore_WRAP(keyclass, BULK_KEY) ||
AES(BULK_KEY, NULL_IV, plainText || padding)
return the plainText. */
bool ks_decrypt_data(keybag_handle_t keybag, CFTypeRef cryptoOp, SecAccessControlRef *paccess_control, CFDataRef acm_context,
CFDataRef blob, const SecDbClass *db_class, CFArrayRef caller_access_groups,
CFMutableDictionaryRef *attributes_p, uint32_t *version_p, bool decryptSecretData, keyclass_t* outKeyclass, CFErrorRef *error) {
const uint32_t v0KeyWrapOverHead = 8;
CFMutableDataRef bulkKey = CFDataCreateMutable(0, 32); /* Use 256 bit AES key for bulkKey. */
CFDataSetLength(bulkKey, 32); /* Use 256 bit AES key for bulkKey. */
bool ok = true;
SecAccessControlRef access_control = NULL;

if (attributes_p)
*attributes_p = NULL;
if (version_p)
*version_p = 0;

CFMutableDataRef plainText = NULL;
CFMutableDictionaryRef attributes = NULL;
uint32_t version = 0;
size_t ivLen = 0;
const uint8_t *iv = NULL;
const uint8_t *aad = NULL; // Additional Authenticated Data
ptrdiff_t aadLen = 0;

#if USE_KEYSTORE
CFMutableDictionaryRef authenticated_attributes = NULL;
CFDataRef caller_access_groups_data = NULL;
CFDataRef ed_data = NULL;
aks_ref_key_t ref_key = NULL;
#if TARGET_OS_IPHONE
check(keybag >= 0);
#else
check((keybag >= 0) || (keybag == session_keybag_handle));
#endif
#endif

if (!blob) {
ok = SecError(errSecParam, error, CFSTR("ks_decrypt_data: invalid blob"));
goto out;
}

size_t blobLen = CFDataGetLength(blob);
const uint8_t *cursor = CFDataGetBytePtr(blob);
keyclass_t keyclass;

if (blobLen < sizeof(version)) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: Check for underflow (length)"));
goto out;
}

version = *((uint32_t *)cursor);
if (version & kUseDefaultIVMask) {
version &= ~kUseDefaultIVMask;
iv = gcmIV;
ivLen = kIVSizeAESGCM;
}

cursor += sizeof(version);
blobLen -= sizeof(version);

bool hasProtectionData = (version >= 4 && version < 7);

if (version >= 7) {
@autoreleasepool {
NSError* localError = nil;
NSData* encryptedBlob = [NSData dataWithBytes:cursor length:blobLen];
SecDbKeychainItemV7* item = [[SecDbKeychainItemV7 alloc] initWithData:encryptedBlob decryptionKeybag:keybag error:&localError];
if (outKeyclass) {
*outKeyclass = item.keyclass;
}

NSMutableDictionary* itemAttributes = [[item metadataAttributesWithError:&localError] mutableCopy];
if (itemAttributes && !localError) {
NSData* accessControlData = itemAttributes[@"SecAccessControl"];
access_control = SecAccessControlCreateFromData(NULL, (__bridge CFDataRef)accessControlData, error);
[itemAttributes removeObjectForKey:@"SecAccessControl"];

if (decryptSecretData) {
NSDictionary* secretAttributes = [item secretAttributesWithAcmContext:(__bridge NSData*)acm_context accessControl:access_control callerAccessGroups:(__bridge NSArray*)caller_access_groups error:&localError];
if (secretAttributes) {
[itemAttributes addEntriesFromDictionary:secretAttributes];
}
else {
ok = false;
}
}

if (ok) {
if (CFEqual(kAKSKeyOpDelete, cryptoOp)) {
ok = [item deleteWithAcmContext:(__bridge NSData*)acm_context accessControl:access_control callerAccessGroups:(__bridge NSArray*)caller_access_groups error:&localError];
}

attributes = (__bridge_retained CFMutableDictionaryRef)itemAttributes;
}
}
else {
ok = false;
}

if (!ok && error) {
*error = (__bridge_retained CFErrorRef)localError;
}
}
goto out;
}

if (hasProtectionData) {
/* Deserialize SecAccessControl object from the blob. */
uint32_t prot_length;

/*
* Parse proto length
*/

if (blobLen < sizeof(prot_length)) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: Check for underflow (prot_length)"));
goto out;
}

prot_length = *((uint32_t *)cursor);
cursor += sizeof(prot_length);
blobLen -= sizeof(prot_length);

/*
* Parse proto itself
*/

if (blobLen < prot_length) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: Check for underflow (prot)"));
goto out;
}

CFTypeRef protection = kc_copy_protection_from(cursor, cursor + prot_length);
if (!protection) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: invalid ACL"));
goto out;
} else {
access_control = SecAccessControlCreate(NULL, NULL);
require_quiet(access_control, out);
ok = SecAccessControlSetProtection(access_control, protection, NULL);
CFRelease(protection);
if (!ok) {
SecError(errSecDecode, error, CFSTR("ks_decrypt_data: invalid ACL"));
goto out;
}
}

cursor += prot_length;
blobLen -= prot_length;

/*
* Get numeric value of keyclass from the access_control.
*/
keyclass = kc_parse_keyclass(SecAccessControlGetProtection(access_control), error);
if (!keyclass) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: invalid ACL"));
goto out;
}
} else {
if (blobLen < sizeof(keyclass)) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: Check for underflow (keyclass)"));
goto out;
}

keyclass = *((keyclass_t *)cursor);

#if USE_KEYSTORE
CFTypeRef protection = kc_encode_keyclass(keyclass & key_class_last); // mask out generation
#else
CFTypeRef protection = kc_encode_keyclass(keyclass);
#endif
require_action_quiet(protection, out, ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: invalid keyclass detected")));
require_action_quiet(access_control = SecAccessControlCreate(kCFAllocatorDefault, error), out,
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: SecAccessControlCreate failed")));
require_action_quiet(SecAccessControlSetProtection(access_control, protection, error), out,
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: SecAccessControlSetProtection failed")));

cursor += sizeof(keyclass);
blobLen -= sizeof(keyclass);
}

size_t tagLen = 0;
uint32_t wrapped_key_size = 0;

switch (version) {
case 0:
wrapped_key_size = (uint32_t)CFDataGetLength(bulkKey) + v0KeyWrapOverHead;
break;
case 2:
case 3:
/* DROPTHROUGH */
/* v2 and v3 have the same crypto, just different dictionary encodings. */
/* Difference between v3 and v6 is already handled above, so treat v3 as v6. */
case 4:
case 5:
case 6:
tagLen = 16;
/* DROPTHROUGH */
case 1:
if (blobLen < sizeof(wrapped_key_size)) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: Check for underflow (wrapped_key_size)"));
goto out;
}
wrapped_key_size = *((uint32_t *)cursor);

cursor += sizeof(wrapped_key_size);
blobLen -= sizeof(wrapped_key_size);

break;
default:
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: invalid version %d"), version);
goto out;
}

if (blobLen < tagLen + wrapped_key_size) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: Check for underflow (wrapped_key/taglen)"));
goto out;
}

size_t ctLen = blobLen - tagLen - wrapped_key_size;

/*
* Pre-version 2 have some additial constraints since it use AES in CBC mode
*/
if (version < 2) {
if (ctLen < kCCBlockSizeAES128) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: Check for underflow (CBC check)"));
goto out;
}
if ((ctLen & 0xF) != 0) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: invalid length on CBC data"));
goto out;
}
}

#if USE_KEYSTORE && !TARGET_OS_SIMULATOR
if (hasProtectionData) {
if (caller_access_groups) {
caller_access_groups_data = kc_copy_access_groups_data(caller_access_groups, error);
require_quiet(ok = (caller_access_groups_data != NULL), out);
}

require_quiet(ok = kc_attribs_key_encrypted_data_from_blob(keybag, db_class, cursor, wrapped_key_size, access_control, version,
&authenticated_attributes, &ref_key, &ed_data, error), out);
if (CFEqual(cryptoOp, kAKSKeyOpDecrypt)) {
require_quiet(ok = ks_decrypt_acl(ref_key, ed_data, bulkKey, acm_context, caller_access_groups_data, access_control, error), out);
} else if (CFEqual(cryptoOp, kAKSKeyOpDelete)) {
require_quiet(ok = ks_delete_acl(ref_key, ed_data, acm_context, caller_access_groups_data, access_control, error), out);
attributes = CFRetainSafe(authenticated_attributes);
goto out;
} else {
ok = SecError(errSecInternal, error, CFSTR("ks_decrypt_data: invalid operation"));
goto out;
}
} else
#endif
{
/* Now unwrap the bulk key using a key in the keybag. */
require_quiet(ok = ks_crypt(cryptoOp, keybag,
keyclass, wrapped_key_size, cursor, NULL, bulkKey, error), out);
}

if (iv) {
// AAD is (version || ... [|| key_wrapped_size ])
aad = CFDataGetBytePtr(blob);
aadLen = cursor - aad;
}

cursor += wrapped_key_size;

plainText = CFDataCreateMutable(NULL, ctLen);
if (!plainText) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: failed to allocate data for plain text"));
goto out;
}
CFDataSetLength(plainText, ctLen);

/* Decrypt the cipherText with the bulkKey. */
CCCryptorStatus ccerr;
if (tagLen) {
uint8_t tag[tagLen];
ccerr = CCCryptorGCM(kCCDecrypt, kCCAlgorithmAES128,
CFDataGetBytePtr(bulkKey), CFDataGetLength(bulkKey),
iv, ivLen, /* iv */
aad, aadLen, /* auth data */
cursor, ctLen,
CFDataGetMutableBytePtr(plainText),
tag, &tagLen);
if (ccerr) {
/* TODO: Should this be errSecDecode once AppleKeyStore correctly
identifies uuid unwrap failures? */
/* errSecInteractionNotAllowed; */
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: CCCryptorGCM failed: %d"), ccerr);
goto out;
}
if (tagLen != 16) {
ok = SecError(errSecInternal, error, CFSTR("ks_decrypt_data: CCCryptorGCM expected: 16 got: %ld byte tag"), tagLen);
goto out;
}
cursor += ctLen;
if (timingsafe_bcmp(tag, cursor, tagLen)) {
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: CCCryptorGCM computed tag not same as tag in blob"));
goto out;
}
} else {
size_t ptLen;
ccerr = CCCrypt(kCCDecrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding,
CFDataGetBytePtr(bulkKey), CFDataGetLength(bulkKey), NULL, cursor, ctLen,
CFDataGetMutableBytePtr(plainText), ctLen, &ptLen);
if (ccerr) {
/* TODO: Should this be errSecDecode once AppleKeyStore correctly
identifies uuid unwrap failures? */
/* errSecInteractionNotAllowed; */
ok = SecError(errSecDecode, error, CFSTR("ks_decrypt_data: CCCrypt failed: %d"), ccerr);
goto out;
}
CFDataSetLength(plainText, ptLen);
}

if (version < 2) {
attributes = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
CFDictionaryAddValue(attributes, CFSTR("v_Data"), plainText);
} else if (version < 3) {
attributes = s3dl_item_v2_decode(plainText, error);
} else {
attributes = s3dl_item_v3_decode(plainText, error);
}

require_action_quiet(attributes, out, { ok = false; secerror("decode v%d failed: %@", version, error ? *error : NULL); });

#if USE_KEYSTORE
if (version >= 4 && authenticated_attributes != NULL) {
CFDictionaryForEach(authenticated_attributes, ^(const void *key, const void *value) {
CFDictionaryAddValue(attributes, key, value);
});
}
#endif

out:
memset(CFDataGetMutableBytePtr(bulkKey), 0, CFDataGetLength(bulkKey));
CFReleaseNull(bulkKey);
CFReleaseNull(plainText);

// Always copy access control data (if present), because if we fail it may indicate why.
if (paccess_control)
*paccess_control = access_control;
else
CFReleaseNull(access_control);

if (ok) {
if (attributes_p)
CFRetainAssign(*attributes_p, attributes);
if (version_p)
*version_p = version;
}
CFReleaseNull(attributes);
#if USE_KEYSTORE
CFReleaseNull(authenticated_attributes);
CFReleaseNull(caller_access_groups_data);
CFReleaseNull(ed_data);
if (ref_key) aks_ref_key_free(&ref_key);
#endif
return ok;
}

static keyclass_t kc_parse_keyclass(CFTypeRef value, CFErrorRef *error) {
if (!isString(value)) {
SecError(errSecParam, error, CFSTR("accessible attribute %@ not a string"), value);
} else if (CFEqual(value, kSecAttrAccessibleWhenUnlocked)) {
return key_class_ak;
} else if (CFEqual(value, kSecAttrAccessibleAfterFirstUnlock)) {
return key_class_ck;
} else if (CFEqual(value, kSecAttrAccessibleAlwaysPrivate)) {
return key_class_dk;
} else if (CFEqual(value, kSecAttrAccessibleWhenUnlockedThisDeviceOnly)) {
return key_class_aku;
} else if (CFEqual(value, kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly)) {
return key_class_cku;
} else if (CFEqual(value, kSecAttrAccessibleAlwaysThisDeviceOnlyPrivate)) {
return key_class_dku;
} else if (CFEqual(value, kSecAttrAccessibleWhenPasscodeSetThisDeviceOnly)) {
return key_class_akpu;
} else {
SecError(errSecParam, error, CFSTR("accessible attribute %@ unknown"), value);
}
return 0;
}

static CFTypeRef kc_encode_keyclass(keyclass_t keyclass) {
switch (keyclass) {
case key_class_ak:
return kSecAttrAccessibleWhenUnlocked;
case key_class_ck:
return kSecAttrAccessibleAfterFirstUnlock;
case key_class_dk:
return kSecAttrAccessibleAlwaysPrivate;
case key_class_aku:
return kSecAttrAccessibleWhenUnlockedThisDeviceOnly;
case key_class_cku:
return kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly;
case key_class_dku:
return kSecAttrAccessibleAlwaysThisDeviceOnlyPrivate;
case key_class_akpu:
return kSecAttrAccessibleWhenPasscodeSetThisDeviceOnly;
default:
return 0;
}
}

// Simulator fakes security, this code is unused on it
#if USE_KEYSTORE && !TARGET_OS_SIMULATOR
static bool kc_attribs_key_encrypted_data_from_blob(keybag_handle_t keybag, const SecDbClass *class, const void *blob_data, size_t blob_data_len, SecAccessControlRef access_control, uint32_t version,
CFMutableDictionaryRef *authenticated_attributes, aks_ref_key_t *ref_key, CFDataRef *encrypted_data, CFErrorRef *error)
{
CFMutableDictionaryRef acl = NULL;
CFDictionaryRef blob_dict = NULL;
aks_ref_key_t tmp_ref_key = NULL;
CFDataRef key_data = NULL;
CFDataRef ed = NULL;
bool ok = false;

der_decode_plist(NULL, kCFPropertyListImmutable, (CFPropertyListRef*)&blob_dict, NULL, blob_data, blob_data + blob_data_len);
require_action_quiet(blob_dict, out, SecError(errSecDecode, error, CFSTR("kc_attribs_key_encrypted_data_from_blob: failed to decode 'blob data'")));

if (!ks_separate_data_and_key(blob_dict, &ed, &key_data)) {
ed = CFDataCreate(kCFAllocatorDefault, blob_data, blob_data_len);
key_data = CFRetain(ed);
}
require_action_quiet(ed, out, SecError(errSecDecode, error, CFSTR("kc_attribs_key_encrypted_data_from_blob: failed to decode 'encrypted data'")));
require_action_quiet(key_data, out, SecError(errSecDecode, error, CFSTR("kc_attribs_key_encrypted_data_from_blob: failed to decode 'key data'")));

const void *external_data = NULL;
size_t external_data_len = 0;
require_quiet(external_data = ks_ref_key_get_external_data(keybag, key_data, &tmp_ref_key, &external_data_len, error), out);

CFPropertyListRef external_data_dict = NULL;
der_decode_plist(NULL, kCFPropertyListImmutable, &external_data_dict, NULL, external_data, external_data + external_data_len);
require_action_quiet(external_data_dict, out, SecError(errSecDecode, error, CFSTR("kc_attribs_key_encrypted_data_from_blob: failed to decode 'encrypted data dictionary'")));
acl = CFDictionaryCreateMutableCopy(NULL, 0, external_data_dict);
SecDbForEachAttrWithMask(class, attr_desc, kSecDbInAuthenticatedDataFlag) {
CFDictionaryRemoveValue(acl, attr_desc->name);
CFTypeRef value = CFDictionaryGetValue(external_data_dict, attr_desc->name);
if (value) {
if (!*authenticated_attributes)
*authenticated_attributes = CFDictionaryCreateMutable(NULL, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);

CFDictionaryAddValue(*authenticated_attributes, attr_desc->name, value);
}
}
CFReleaseSafe(external_data_dict);

if (acl) {
/* v4 data format used wrong ACL placement, for backward compatibility we have to support both formats */
if (version == 4) {
SecAccessControlSetConstraints(access_control, acl);
} else {
CFDictionaryRef constraints = CFDictionaryGetValue(acl, kAKSKeyAcl);
require_action_quiet(isDictionary(constraints), out,
SecError(errSecDecode, error, CFSTR("kc_attribs_key_encrypted_data_from_blob: acl missing")));
SecAccessControlSetConstraints(access_control, constraints);
}

/* v4/v5 data format usualy does not contain kAKSKeyOpEncrypt, so add kAKSKeyOpEncrypt if is missing */
if (version < 6) {
SecAccessConstraintRef encryptConstraint = SecAccessControlGetConstraint(access_control, kAKSKeyOpEncrypt);
if (!encryptConstraint)
SecAccessControlAddConstraintForOperation(access_control, kAKSKeyOpEncrypt, kCFBooleanTrue, NULL);
}

}

if (encrypted_data)
*encrypted_data = CFRetain(ed);

if (ref_key) {
*ref_key = tmp_ref_key;
tmp_ref_key = NULL;
}

ok = true;

out:
if (tmp_ref_key)
aks_ref_key_free(&tmp_ref_key);
CFReleaseSafe(blob_dict);
CFReleaseSafe(key_data);
CFReleaseSafe(ed);
CFReleaseSafe(acl);

return ok;
}

static CFDataRef kc_create_auth_data(SecAccessControlRef access_control, CFDictionaryRef auth_attributes) {
CFDictionaryRef constraints = SecAccessControlGetConstraints(access_control);
CFMutableDictionaryRef auth_data = CFDictionaryCreateMutableCopy(NULL, 0, auth_attributes);
CFDictionarySetValue(auth_data, kAKSKeyAcl, constraints);
CFDataRef encoded = CFPropertyListCreateDERData(kCFAllocatorDefault, auth_data, NULL);
CFReleaseSafe(auth_data);
return encoded;
}

static CFDataRef kc_copy_access_groups_data(CFArrayRef access_groups, CFErrorRef *error)
{
size_t ag_size = der_sizeof_plist(access_groups, error);
CFMutableDataRef result = CFDataCreateMutable(kCFAllocatorDefault, 0);
CFDataSetLength(result, ag_size);
if (!der_encode_plist(access_groups, error, CFDataGetMutableBytePtr(result), CFDataGetMutableBytePtr(result) + ag_size)) {
CFRelease(result);
return NULL;
}
else
return result;
}

#endif /* USE_KEYSTORE */

static CFDataRef kc_copy_protection_data(SecAccessControlRef access_control)
{
CFTypeRef protection = SecAccessControlGetProtection(access_control);
size_t protection_size = der_sizeof_plist(protection, NULL);
CFMutableDataRef result = CFDataCreateMutable(NULL, 0);
CFDataSetLength(result, protection_size);
if (!der_encode_plist(protection, NULL, CFDataGetMutableBytePtr(result), CFDataGetMutableBytePtr(result) + protection_size)) {
CFRelease(result);
return NULL;
}
else
return result;
}

static CFTypeRef kc_copy_protection_from(const uint8_t *der, const uint8_t *der_end)
{
CFTypeRef result = NULL;
der_decode_plist(NULL, kCFPropertyListImmutable, &result, NULL, der, der_end);
return result;
}

/* Return a (mutable) dictionary if plist is a dictionary, return NULL and set error otherwise. Does nothing if plist is already NULL. */
static CF_RETURNS_RETAINED
CFMutableDictionaryRef dictionaryFromPlist(CFPropertyListRef plist CF_CONSUMED, CFErrorRef *error) {
if (plist && !isDictionary(plist)) {
CFStringRef typeName = CFCopyTypeIDDescription(CFGetTypeID((CFTypeRef)plist));
SecError(errSecDecode, error, CFSTR("plist is a %@, expecting a dictionary"), typeName);
CFReleaseSafe(typeName);
CFReleaseNull(plist);
}
return (CFMutableDictionaryRef)plist;
}

static CF_RETURNS_RETAINED
CFMutableDictionaryRef s3dl_item_v2_decode(CFDataRef plain, CFErrorRef *error) {
CFPropertyListRef item;
item = CFPropertyListCreateWithData(0, plain, kCFPropertyListMutableContainers, NULL, error);
return dictionaryFromPlist(item, error);
}

static const uint8_t* (^s3dl_item_v3_decode_repair_date)(CFAllocatorRef, CFOptionFlags, CFPropertyListRef*, CFErrorRef*, const uint8_t*, const uint8_t*) =
^const uint8_t*(CFAllocatorRef allocator, CFOptionFlags mutability, CFPropertyListRef* pl, CFErrorRef *error, const uint8_t* der, const uint8_t *der_end) {
if (error && CFEqualSafe(CFErrorGetDomain(*error), sSecDERErrorDomain) && CFErrorGetCode(*error) == kSecDERErrorUnknownEncoding) {
CFAbsoluteTime date = 0;
CFCalendarRef calendar = CFCalendarCreateWithIdentifier(allocator, kCFGregorianCalendar);
CFTimeZoneRef tz = CFTimeZoneCreateWithTimeIntervalFromGMT(allocator, 0);
CFCalendarSetTimeZone(calendar, tz);
CFCalendarComposeAbsoluteTime(calendar, &date, "yMd", 2001, 3, 24); // random date for <rdar://problem/20458954> 15A143: can't recover keychain
CFReleaseSafe(tz);
CFReleaseSafe(calendar);

*pl = CFDateCreate(allocator, date);
if (NULL != *pl) {
CFReleaseNull(*error);
return der_end;
}
}
return NULL;
};

static CF_RETURNS_RETAINED
CFMutableDictionaryRef s3dl_item_v3_decode(CFDataRef plain, CFErrorRef *error) {
CFPropertyListRef item = NULL;
const uint8_t *der_beg = CFDataGetBytePtr(plain);
const uint8_t *der_end = der_beg + CFDataGetLength(plain);
const uint8_t *der = der_decode_plist(0, kCFPropertyListMutableContainers, &item, error, der_beg, der_end);
if (!der && error && CFEqualSafe(CFErrorGetDomain(*error), sSecDERErrorDomain) && CFErrorGetCode(*error) == kSecDERErrorUnknownEncoding) {
CFReleaseNull(*error);
der = der_decode_plist_with_repair(0, kCFPropertyListMutableContainers, &item, error, der_beg, der_end, s3dl_item_v3_decode_repair_date);
}
if (der && der != der_end) {
SecCFCreateError(errSecDecode, kSecErrorDomain, CFSTR("trailing garbage at end of decrypted item"), NULL, error);
CFReleaseNull(item);
}
return dictionaryFromPlist(item, error);
}

bool s3dl_item_from_data(CFDataRef edata, Query *q, CFArrayRef accessGroups,
CFMutableDictionaryRef *item, SecAccessControlRef *access_control, keyclass_t* keyclass, CFErrorRef *error) {
SecAccessControlRef ac = NULL;
CFDataRef ac_data = NULL;
bool ok = false;

/* Decrypt and decode the item and check the decoded attributes against the query. */
uint32_t version = 0;

bool decryptSecretData = false;
if ((q->q_return_type & kSecReturnDataMask) || (q->q_return_type & kSecReturnRefMask)) {
decryptSecretData = true;
}
else if (q->q_match_policy || q->q_match_valid_on_date || q->q_match_trusted_only) {
decryptSecretData = true;
}

require_quiet((ok = ks_decrypt_data(q->q_keybag, kAKSKeyOpDecrypt, &ac, q->q_use_cred_handle, edata, q->q_class,
q->q_caller_access_groups, item, &version, decryptSecretData, keyclass, error)), out);
if (version < 2) {
SecError(errSecDecode, error, CFSTR("version is unexpected: %d"), (int)version);
ok = false;
goto out;
}

ac_data = SecAccessControlCopyData(ac);
if (!itemInAccessGroup(*item, accessGroups)) {
secerror("items accessGroup '%@' not in %@",
CFDictionaryGetValue(*item, kSecAttrAccessGroup),
accessGroups);
// We likely don't want to surface it to clients like this, but this is most accurate
SecError(errSecMissingEntitlement, error, CFSTR("item's access group '%@' not in %@"),
CFDictionaryGetValue(*item, kSecAttrAccessGroup), accessGroups);
CFReleaseNull(*item);
ok = false;
goto out;
}

/* AccessControl attribute does not exist in the db, so synthesize it. */
if (version > 3)
CFDictionarySetValue(*item, kSecAttrAccessControl, ac_data);

/* TODO: Validate access_control attribute. */

out:
if (access_control)
*access_control = CFRetainSafe(ac);
CFReleaseSafe(ac);
CFReleaseSafe(ac_data);
return ok;
}

/* Infer accessibility and access group for pre-v2 (iOS4.x and earlier) items
being imported from a backup. */
static bool SecDbItemImportMigrate(SecDbItemRef item, CFErrorRef *error) {
bool ok = true;
CFStringRef agrp = SecDbItemGetCachedValueWithName(item, kSecAttrAccessGroup);
CFStringRef accessible = SecDbItemGetCachedValueWithName(item, kSecAttrAccessible);

if (!isString(agrp) || !isString(accessible))
return ok;
if (SecDbItemGetClass(item) == genp_class() && CFEqual(accessible, kSecAttrAccessibleAlwaysPrivate)) {
CFStringRef svce = SecDbItemGetCachedValueWithName(item, kSecAttrService);
if (!isString(svce)) return ok;
if (CFEqual(agrp, CFSTR("apple"))) {
if (CFEqual(svce, CFSTR("AirPort"))) {
ok = SecDbItemSetValueWithName(item, kSecAttrAccessible, kSecAttrAccessibleAfterFirstUnlock, error);
} else if (CFEqual(svce, CFSTR("com.apple.airplay.password"))) {
ok = SecDbItemSetValueWithName(item, kSecAttrAccessible, kSecAttrAccessibleWhenUnlocked, error);
} else if (CFEqual(svce, CFSTR("YouTube"))) {
ok = (SecDbItemSetValueWithName(item, kSecAttrAccessible, kSecAttrAccessibleWhenUnlocked, error) &&
SecDbItemSetValueWithName(item, kSecAttrAccessGroup, CFSTR("com.apple.youtube.credentials"), error));
} else {
CFStringRef desc = SecDbItemGetCachedValueWithName(item, kSecAttrDescription);
if (!isString(desc)) return ok;
if (CFEqual(desc, CFSTR("IPSec Shared Secret")) || CFEqual(desc, CFSTR("PPP Password"))) {
ok = SecDbItemSetValueWithName(item, kSecAttrAccessible, kSecAttrAccessibleAfterFirstUnlock, error);
}
}
}
} else if (SecDbItemGetClass(item) == inet_class() && CFEqual(accessible, kSecAttrAccessibleAlwaysPrivate)) {
if (CFEqual(agrp, CFSTR("PrintKitAccessGroup"))) {
ok = SecDbItemSetValueWithName(item, kSecAttrAccessible, kSecAttrAccessibleWhenUnlocked, error);
} else if (CFEqual(agrp, CFSTR("apple"))) {
CFTypeRef ptcl = SecDbItemGetCachedValueWithName(item, kSecAttrProtocol);
bool is_proxy = false;
if (isNumber(ptcl)) {
SInt32 iptcl;
CFNumberGetValue(ptcl, kCFNumberSInt32Type, &iptcl);
is_proxy = (iptcl == FOUR_CHAR_CODE('htpx') ||
iptcl == FOUR_CHAR_CODE('htsx') ||
iptcl == FOUR_CHAR_CODE('ftpx') ||
iptcl == FOUR_CHAR_CODE('rtsx') ||
iptcl == FOUR_CHAR_CODE('xpth') ||
iptcl == FOUR_CHAR_CODE('xsth') ||
iptcl == FOUR_CHAR_CODE('xptf') ||
iptcl == FOUR_CHAR_CODE('xstr'));
} else if (isString(ptcl)) {
is_proxy = (CFEqual(ptcl, kSecAttrProtocolHTTPProxy) ||
CFEqual(ptcl, kSecAttrProtocolHTTPSProxy) ||
CFEqual(ptcl, kSecAttrProtocolRTSPProxy) ||
CFEqual(ptcl, kSecAttrProtocolFTPProxy));
}
if (is_proxy)
ok = SecDbItemSetValueWithName(item, kSecAttrAccessible, kSecAttrAccessibleWhenUnlocked, error);
}
}
return ok;
}

bool SecDbItemDecrypt(SecDbItemRef item, bool decryptSecretData, CFDataRef edata, CFErrorRef *error) {
bool ok = true;
CFMutableDictionaryRef dict = NULL;
SecAccessControlRef access_control = NULL;
uint32_t version = 0;

require_quiet(ok = ks_decrypt_data(SecDbItemGetKeybag(item), item->cryptoOp, &access_control, item->credHandle, edata,
item->class, item->callerAccessGroups, &dict, &version, decryptSecretData, NULL, error), out);

if (version < 2) {
/* Old V4 style keychain backup being imported. */
ok = SecDbItemSetValueWithName(item, CFSTR("v_Data"), CFDictionaryGetValue(dict, CFSTR("v_Data")), error) &&
SecDbItemImportMigrate(item, error);
} else {
ok = dict && SecDbItemSetValues(item, dict, error);
}

SecAccessControlRef my_access_control = SecDbItemCopyAccessControl(item, error);
if (!my_access_control) {
ok = false;
goto out;
}

/* Make sure that the protection of ACL in the dictionary (read from DB) matched what we got
back from decoding the data blob. */
if (!CFEqual(SecAccessControlGetProtection(my_access_control), SecAccessControlGetProtection(access_control))) {
ok = SecError(errSecDecode, error, CFSTR("ACL protection doesn't match the one in blob (%@ : %@)"),
SecAccessControlGetProtection(my_access_control),
SecAccessControlGetProtection(access_control));
}
CFRelease(my_access_control);

out:
// If we got protection back from ks_decrypt_data, update the appropriate attribute even if anything else
// (incl. actual decryption) failed. We need to access the protection type even if we are not able to actually
// decrypt the data.
ok = SecDbItemSetAccessControl(item, access_control, NULL) && ok;

CFReleaseSafe(dict);
CFReleaseSafe(access_control);
return ok;
}

/* Automagically make a item syncable, based on various attributes. */
bool SecDbItemInferSyncable(SecDbItemRef item, CFErrorRef *error)
{
CFStringRef agrp = SecDbItemGetCachedValueWithName(item, kSecAttrAccessGroup);

if (!isString(agrp))
return true;

if (CFEqual(agrp, CFSTR("com.apple.cfnetwork")) && SecDbItemGetClass(item) == inet_class()) {
CFTypeRef srvr = SecDbItemGetCachedValueWithName(item, kSecAttrServer);
CFTypeRef ptcl = SecDbItemGetCachedValueWithName(item, kSecAttrProtocol);
CFTypeRef atyp = SecDbItemGetCachedValueWithName(item, kSecAttrAuthenticationType);

if (isString(srvr) && isString(ptcl) && isString(atyp)) {
/* This looks like a Mobile Safari Password, make syncable */
secnotice("item", "Make this item syncable: %@", item);
return SecDbItemSetSyncable(item, true, error);
}
}

return true;
}

/* This create a SecDbItem from the item dictionnary that are exported for backups.
Item are stored in the backup as a dictionary containing two keys:
- v_Data: the encrypted data blob
- v_PersistentRef: a persistent Ref.
src_keybag is normally the backup keybag.
dst_keybag is normally the device keybag.
*/
SecDbItemRef SecDbItemCreateWithBackupDictionary(CFAllocatorRef allocator, const SecDbClass *dbclass, CFDictionaryRef dict, keybag_handle_t src_keybag, keybag_handle_t dst_keybag, CFErrorRef *error)
{
CFDataRef edata = CFDictionaryGetValue(dict, CFSTR("v_Data"));
SecDbItemRef item = NULL;

if (edata) {
item = SecDbItemCreateWithEncryptedData(kCFAllocatorDefault, dbclass, edata, src_keybag, error);
if (item)
if (!SecDbItemSetKeybag(item, dst_keybag, error))
CFReleaseNull(item);
} else {
SecError(errSecDecode, error, CFSTR("No v_Data in backup dictionary %@"), dict);
}

return item;
}

bool SecDbItemExtractRowIdFromBackupDictionary(SecDbItemRef item, CFDictionaryRef dict, CFErrorRef *error) {
CFDataRef ref = CFDictionaryGetValue(dict, CFSTR("v_PersistentRef"));
if (!ref)
return SecError(errSecDecode, error, CFSTR("No v_PersistentRef in backup dictionary %@"), dict);

CFStringRef className;
sqlite3_int64 rowid;
if (!_SecItemParsePersistentRef(ref, &className, &rowid, NULL))
return SecError(errSecDecode, error, CFSTR("v_PersistentRef %@ failed to decode"), ref);

if (!CFEqual(SecDbItemGetClass(item)->name, className))
return SecError(errSecDecode, error, CFSTR("v_PersistentRef has unexpected class %@"), className);

return SecDbItemSetRowId(item, rowid, error);
}

static CFDataRef SecDbItemCopyDERWithMask(SecDbItemRef item, CFOptionFlags mask, CFErrorRef *error) {
CFDataRef der = NULL;
CFMutableDictionaryRef dict = SecDbItemCopyPListWithMask(item, mask, error);
if (dict) {
der = CFPropertyListCreateDERData(kCFAllocatorDefault, dict, error);
CFRelease(dict);
}
return der;
}

static CFTypeRef SecDbItemCopyDigestWithMask(SecDbItemRef item, CFOptionFlags mask, CFErrorRef *error) {
CFDataRef digest = NULL;
CFDataRef der = SecDbItemCopyDERWithMask(item, mask, error);
if (der) {
digest = CFDataCopySHA1Digest(der, error);
CFRelease(der);
}
return digest;
}

static CFTypeRef SecDbItemCopySHA256DigestWithMask(SecDbItemRef item, CFOptionFlags mask, CFErrorRef *error) {
CFDataRef digest = NULL;
CFDataRef der = SecDbItemCopyDERWithMask(item, mask, error);
if (der) {
digest = CFDataCopySHA256Digest(der, error);
CFRelease(der);
}
return digest;
}

CFTypeRef SecDbKeychainItemCopyPrimaryKey(SecDbItemRef item, const SecDbAttr *attr, CFErrorRef *error) {
return SecDbItemCopyDigestWithMask(item, kSecDbPrimaryKeyFlag, error);
}

CFTypeRef SecDbKeychainItemCopySHA256PrimaryKey(SecDbItemRef item, CFErrorRef *error) {
return SecDbItemCopySHA256DigestWithMask(item, kSecDbPrimaryKeyFlag, error);
}

CFTypeRef SecDbKeychainItemCopySHA1(SecDbItemRef item, const SecDbAttr *attr, CFErrorRef *error) {
return SecDbItemCopyDigestWithMask(item, kSecDbInHashFlag, error);
}

CFTypeRef SecDbKeychainItemCopyEncryptedData(SecDbItemRef item, const SecDbAttr *attr, CFErrorRef *error) {
CFDataRef edata = NULL;
CFDataRef bkuuid = NULL;
CFMutableDictionaryRef secretStuff = SecDbItemCopyPListWithMask(item, kSecDbReturnDataFlag, error);
CFMutableDictionaryRef attributes = SecDbItemCopyPListWithMask(item, kSecDbInCryptoDataFlag, error);
CFMutableDictionaryRef auth_attributes = SecDbItemCopyPListWithMask(item, kSecDbInAuthenticatedDataFlag, error);
if (secretStuff || attributes || auth_attributes) {
SecAccessControlRef access_control = SecDbItemCopyAccessControl(item, error);
CFDataRef sha1 = SecDbKeychainItemCopySHA1(item, attr, error);
if (access_control && sha1) {
if (!auth_attributes) {
auth_attributes = CFDictionaryCreateMutable(NULL, 1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
}
CFDictionarySetValue(auth_attributes, kSecAttrSHA1, sha1);

CFDictionaryForEach(secretStuff, ^(const void *key, const void *value) {
CFDictionaryRemoveValue(attributes, key);
CFDictionaryRemoveValue(auth_attributes, key);
});

if (ks_encrypt_data_with_backupuuid(item->keybag, access_control, item->credHandle, secretStuff, attributes, auth_attributes, &edata, &bkuuid, true, error)) {
item->_edataState = kSecDbItemEncrypting;
} else if (!error || !*error || CFErrorGetCode(*error) != errSecAuthNeeded || !CFEqualSafe(CFErrorGetDomain(*error), kSecErrorDomain) ) {
seccritical("ks_encrypt_data (db): failed: %@", error ? *error : (CFErrorRef)CFSTR(""));
}
CFRelease(access_control);
}
CFReleaseNull(secretStuff);
CFReleaseNull(attributes);
CFReleaseNull(auth_attributes);
CFReleaseNull(sha1);
if (bkuuid) {
// "data" is defined first in the schema so called first. The UUID will therefore be in the cache when ForEach gets to it
CFErrorRef localError = NULL;
SecDbItemSetValueWithName(item, CFSTR("backupUUID"), bkuuid, &localError);
if (localError) {
// Don't want to propagate this. It's bad but should be handled in the manager and not interrupt production
secerror("Unable to wrap keychain item to backup: %@", localError);
CFReleaseNull(localError);
CFReleaseNull(bkuuid);
}
}
}
return edata;
}

CFTypeRef SecDbKeychainItemCopyCurrentDate(SecDbItemRef item, const SecDbAttr *attr, CFErrorRef *error) {
CFTypeRef value = NULL;
switch (attr->kind) {
case kSecDbDateAttr:
value = CFDateCreate(kCFAllocatorDefault, 0.0);
break;
case kSecDbCreationDateAttr:
case kSecDbModificationDateAttr:
value = CFDateCreate(kCFAllocatorDefault, CFAbsoluteTimeGetCurrent());
break;
default:
SecError(errSecInternal, error, CFSTR("attr %@ has no default value"), attr->name);
value = NULL;
}

return value;
}

SecAccessControlRef SecDbItemCopyAccessControl(SecDbItemRef item, CFErrorRef *error) {
SecAccessControlRef accc = NULL, pdmn = NULL, result = NULL;
CFTypeRef acccData = SecDbItemGetValue(item, SecDbClassAttrWithKind(item->class, kSecDbAccessControlAttr, error), error);
CFTypeRef pdmnValue = SecDbItemGetValue(item, SecDbClassAttrWithKind(item->class, kSecDbAccessAttr, error), error);

if (!acccData || !pdmnValue)
return NULL;
if (!CFEqual(acccData, kCFNull))
require_quiet(accc = SecAccessControlCreateFromData(CFGetAllocator(item), acccData, error), out);

if (!CFEqual(pdmnValue, kCFNull)) {
require_quiet(pdmn = SecAccessControlCreate(CFGetAllocator(item), error), out);
require_quiet(SecAccessControlSetProtection(pdmn, pdmnValue, error), out);
}

if (accc && pdmn) {
CFTypeRef acccProt = SecAccessControlGetProtection(accc);
CFTypeRef pdmnProt = SecAccessControlGetProtection(pdmn);
if (!acccProt || !pdmnProt || !CFEqual(acccProt, pdmnProt)) {
secerror("SecDbItemCopyAccessControl accc %@ != pdmn %@, setting pdmn to accc value", acccProt, pdmnProt);
__security_simulatecrash(CFSTR("Corrupted item on decrypt accc != pdmn"), __sec_exception_code_CorruptItem);
// Setting pdmn to accc prot value.
require_quiet(SecDbItemSetValue(item, SecDbClassAttrWithKind(item->class, kSecDbAccessAttr, error), acccProt, error), out);
}
}

if (accc)
CFRetainAssign(result, accc);
else if(pdmn)
CFRetainAssign(result, pdmn);

out:
CFReleaseSafe(accc);
CFReleaseSafe(pdmn);

return result;
}

static const uint8_t* der_decode_plist_with_repair(CFAllocatorRef allocator, CFOptionFlags mutability,
CFPropertyListRef* pl, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef, CFOptionFlags, CFPropertyListRef*, CFErrorRef*,
const uint8_t*, const uint8_t*))
{
if (NULL == der) {
SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Null DER"), NULL, error);
return NULL;
}

ccder_tag tag;
if (NULL == ccder_decode_tag(&tag, der, der_end)) {
SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Unknown data encoding"), NULL, error);
return NULL;
}

switch (tag) {
case CCDER_NULL:
return der_decode_null(allocator, mutability, (CFNullRef*)pl, error, der, der_end);
case CCDER_BOOLEAN:
return der_decode_boolean(allocator, mutability, (CFBooleanRef*)pl, error, der, der_end);
case CCDER_OCTET_STRING:
return der_decode_data(allocator, mutability, (CFDataRef*)pl, error, der, der_end);
case CCDER_GENERALIZED_TIME: {
const uint8_t* der_result = der_decode_date(allocator, mutability, (CFDateRef*)pl, error, der, der_end);
if (!der_result) {
der_result = repairBlock(allocator, mutability, pl, error, der, der_end);
}
return der_result;
}
case CCDER_CONSTRUCTED_SEQUENCE:
return der_decode_array_with_repair(allocator, mutability, (CFArrayRef*)pl, error, der, der_end, repairBlock);
case CCDER_UTF8_STRING:
return der_decode_string(allocator, mutability, (CFStringRef*)pl, error, der, der_end);
case CCDER_INTEGER:
return der_decode_number(allocator, mutability, (CFNumberRef*)pl, error, der, der_end);
case CCDER_CONSTRUCTED_SET:
return der_decode_dictionary_with_repair(allocator, mutability, (CFDictionaryRef*)pl, error, der, der_end, repairBlock);
case CCDER_CONSTRUCTED_CFSET:
return der_decode_set_with_repair(allocator, mutability, (CFSetRef*)pl, error, der, der_end, repairBlock);
default:
SecCFDERCreateError(kSecDERErrorUnsupportedDERType, CFSTR("Unsupported DER Type"), NULL, error);
return NULL;
}
}

static const uint8_t* der_decode_dictionary_with_repair(CFAllocatorRef allocator, CFOptionFlags mutability,
CFDictionaryRef* dictionary, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef, CFOptionFlags, CFPropertyListRef*, CFErrorRef*,
const uint8_t*, const uint8_t*))
{
if (NULL == der) {
SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Null DER"), NULL, error);
return NULL;
}

const uint8_t *payload_end = 0;
const uint8_t *payload = ccder_decode_constructed_tl(CCDER_CONSTRUCTED_SET, &payload_end, der, der_end);

if (NULL == payload) {
SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Unknown data encoding, expected CCDER_CONSTRUCTED_SET"), NULL, error);
return NULL;
}

CFMutableDictionaryRef dict = CFDictionaryCreateMutable(allocator, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);

if (NULL == dict) {
SecCFDERCreateError(kSecDERErrorAllocationFailure, CFSTR("Failed to create dictionary"), NULL, error);
payload = NULL;
goto exit;
}

while (payload != NULL && payload < payload_end) {
CFTypeRef key = NULL;
CFTypeRef value = NULL;

payload = der_decode_key_value_with_repair(allocator, mutability, &key, &value, error, payload, payload_end, repairBlock);

if (payload) {
CFDictionaryAddValue(dict, key, value);
}

CFReleaseNull(key);
CFReleaseNull(value);
}

exit:
if (payload == payload_end) {
*dictionary = dict;
dict = NULL;
}

CFReleaseNull(dict);

return payload;
}

static const uint8_t* der_decode_key_value_with_repair(CFAllocatorRef allocator, CFOptionFlags mutability,
CFPropertyListRef* key, CFPropertyListRef* value, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef, CFOptionFlags, CFPropertyListRef*, CFErrorRef*,
const uint8_t*, const uint8_t*))
{
const uint8_t *payload_end = 0;
const uint8_t *payload = ccder_decode_constructed_tl(CCDER_CONSTRUCTED_SEQUENCE, &payload_end, der, der_end);

if (NULL == payload) {
SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Unknown data encoding, expected CCDER_CONSTRUCTED_SEQUENCE"), NULL, error);
return NULL;
}

CFTypeRef keyObject = NULL;
CFTypeRef valueObject = NULL;

payload = der_decode_plist_with_repair(allocator, mutability, &keyObject, error, payload, payload_end, repairBlock);
payload = der_decode_plist_with_repair(allocator, mutability, &valueObject, error, payload, payload_end, repairBlock);

if (payload != NULL) {
*key = keyObject;
*value = valueObject;
} else {
CFReleaseNull(keyObject);
CFReleaseNull(valueObject);
}
return payload;
}

static const uint8_t* der_decode_array_with_repair(CFAllocatorRef allocator, CFOptionFlags mutability,
CFArrayRef* array, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef, CFOptionFlags, CFPropertyListRef*, CFErrorRef*,
const uint8_t*, const uint8_t*))
{
if (NULL == der) {
SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Null DER"), NULL, error);
return NULL;
}

CFMutableArrayRef result = CFArrayCreateMutable(allocator, 0, &kCFTypeArrayCallBacks);

const uint8_t *elements_end;
const uint8_t *current_element = ccder_decode_sequence_tl(&elements_end, der, der_end);

while (current_element != NULL && current_element < elements_end) {
CFPropertyListRef element = NULL;
current_element = der_decode_plist_with_repair(allocator, mutability, &element, error, current_element, elements_end, repairBlock);
if (current_element) {
CFArrayAppendValue(result, element);
CFReleaseNull(element);
}
}

if (current_element) {
*array = result;
result = NULL;
}

CFReleaseNull(result);
return current_element;
}

static const uint8_t* der_decode_set_with_repair(CFAllocatorRef allocator, CFOptionFlags mutability,
CFSetRef* set, CFErrorRef *error,
const uint8_t* der, const uint8_t *der_end,
const uint8_t* (^repairBlock)(CFAllocatorRef, CFOptionFlags, CFPropertyListRef*, CFErrorRef*,
const uint8_t*, const uint8_t*))
{
if (NULL == der) {
SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Null DER"), NULL, error);
return NULL;
}

const uint8_t *payload_end = 0;
const uint8_t *payload = ccder_decode_constructed_tl(CCDER_CONSTRUCTED_CFSET, &payload_end, der, der_end);

if (NULL == payload) {
SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Unknown data encoding, expected CCDER_CONSTRUCTED_CFSET"), NULL, error);
return NULL;
}

CFMutableSetRef theSet = (set && *set) ? CFSetCreateMutableCopy(allocator, 0, *set)
: CFSetCreateMutable(allocator, 0, &kCFTypeSetCallBacks);

if (NULL == theSet) {
SecCFDERCreateError(kSecDERErrorAllocationFailure, CFSTR("Failed to create set"), NULL, error);
payload = NULL;
goto exit;
}

while (payload != NULL && payload < payload_end) {
CFTypeRef value = NULL;

payload = der_decode_plist_with_repair(allocator, mutability, &value, error, payload, payload_end, repairBlock);

if (payload) {
CFSetAddValue(theSet, value);
}
CFReleaseNull(value);
}

exit:
if (set && payload == payload_end) {
CFTransferRetained(*set, theSet);
}

CFReleaseNull(theSet);

return payload;
}

void SecDbResetMetadataKeys(void) {
[SecDbKeychainMetadataKeyStore resetSharedStore];
}