OLMKit: add Short Authentication String verification
(cherry picked from commit 3e954ca2729d3333ea853c878602d1696f616573)
This commit is contained in:
parent
3609227c6e
commit
5de295da3e
6 changed files with 280 additions and 7 deletions
|
@ -12,6 +12,7 @@
|
||||||
3274F6071D9A633A005282E4 /* OLMKitTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 3274F6061D9A633A005282E4 /* OLMKitTests.m */; };
|
3274F6071D9A633A005282E4 /* OLMKitTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 3274F6061D9A633A005282E4 /* OLMKitTests.m */; };
|
||||||
3274F6131D9A698E005282E4 /* OLMKit.h in Headers */ = {isa = PBXBuildFile; fileRef = 3274F6121D9A698E005282E4 /* OLMKit.h */; };
|
3274F6131D9A698E005282E4 /* OLMKit.h in Headers */ = {isa = PBXBuildFile; fileRef = 3274F6121D9A698E005282E4 /* OLMKit.h */; };
|
||||||
32A151311DABDD4300400192 /* OLMKitGroupTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 32A151301DABDD4300400192 /* OLMKitGroupTests.m */; };
|
32A151311DABDD4300400192 /* OLMKitGroupTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 32A151301DABDD4300400192 /* OLMKitGroupTests.m */; };
|
||||||
|
32F143AF2236B4100077CF37 /* OLMKitSASTests.m in Sources */ = {isa = PBXBuildFile; fileRef = 32F143AE2236B4100077CF37 /* OLMKitSASTests.m */; };
|
||||||
7DBAD311AEA85CF6DB80DCFA /* libPods-OLMKitTests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 7123FABE917D0FB140E036B7 /* libPods-OLMKitTests.a */; };
|
7DBAD311AEA85CF6DB80DCFA /* libPods-OLMKitTests.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 7123FABE917D0FB140E036B7 /* libPods-OLMKitTests.a */; };
|
||||||
D667051A0BA47E17CCC4E5D7 /* libPods-OLMKit.a in Frameworks */ = {isa = PBXBuildFile; fileRef = F2F22FE8F173AF845B882805 /* libPods-OLMKit.a */; };
|
D667051A0BA47E17CCC4E5D7 /* libPods-OLMKit.a in Frameworks */ = {isa = PBXBuildFile; fileRef = F2F22FE8F173AF845B882805 /* libPods-OLMKit.a */; };
|
||||||
/* End PBXBuildFile section */
|
/* End PBXBuildFile section */
|
||||||
|
@ -36,6 +37,7 @@
|
||||||
3274F6081D9A633A005282E4 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
|
3274F6081D9A633A005282E4 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
|
||||||
3274F6121D9A698E005282E4 /* OLMKit.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = OLMKit.h; sourceTree = "<group>"; };
|
3274F6121D9A698E005282E4 /* OLMKit.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = OLMKit.h; sourceTree = "<group>"; };
|
||||||
32A151301DABDD4300400192 /* OLMKitGroupTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OLMKitGroupTests.m; sourceTree = "<group>"; };
|
32A151301DABDD4300400192 /* OLMKitGroupTests.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = OLMKitGroupTests.m; sourceTree = "<group>"; };
|
||||||
|
32F143AE2236B4100077CF37 /* OLMKitSASTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = OLMKitSASTests.m; sourceTree = "<group>"; };
|
||||||
7123FABE917D0FB140E036B7 /* libPods-OLMKitTests.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = "libPods-OLMKitTests.a"; sourceTree = BUILT_PRODUCTS_DIR; };
|
7123FABE917D0FB140E036B7 /* libPods-OLMKitTests.a */ = {isa = PBXFileReference; explicitFileType = archive.ar; includeInIndex = 0; path = "libPods-OLMKitTests.a"; sourceTree = BUILT_PRODUCTS_DIR; };
|
||||||
875BA7A520258EA15A31DD82 /* Pods-OLMKitTests.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-OLMKitTests.debug.xcconfig"; path = "Pods/Target Support Files/Pods-OLMKitTests/Pods-OLMKitTests.debug.xcconfig"; sourceTree = "<group>"; };
|
875BA7A520258EA15A31DD82 /* Pods-OLMKitTests.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-OLMKitTests.debug.xcconfig"; path = "Pods/Target Support Files/Pods-OLMKitTests/Pods-OLMKitTests.debug.xcconfig"; sourceTree = "<group>"; };
|
||||||
D48E486DAE1F59F4F7EA8C25 /* Pods-OLMKitTests.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-OLMKitTests.release.xcconfig"; path = "Pods/Target Support Files/Pods-OLMKitTests/Pods-OLMKitTests.release.xcconfig"; sourceTree = "<group>"; };
|
D48E486DAE1F59F4F7EA8C25 /* Pods-OLMKitTests.release.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-OLMKitTests.release.xcconfig"; path = "Pods/Target Support Files/Pods-OLMKitTests/Pods-OLMKitTests.release.xcconfig"; sourceTree = "<group>"; };
|
||||||
|
@ -107,6 +109,7 @@
|
||||||
3274F6051D9A633A005282E4 /* OLMKitTests */ = {
|
3274F6051D9A633A005282E4 /* OLMKitTests */ = {
|
||||||
isa = PBXGroup;
|
isa = PBXGroup;
|
||||||
children = (
|
children = (
|
||||||
|
32F143AE2236B4100077CF37 /* OLMKitSASTests.m */,
|
||||||
3244277C2175EF700023EDF1 /* OLMKitPkTests.m */,
|
3244277C2175EF700023EDF1 /* OLMKitPkTests.m */,
|
||||||
3274F6061D9A633A005282E4 /* OLMKitTests.m */,
|
3274F6061D9A633A005282E4 /* OLMKitTests.m */,
|
||||||
32A151301DABDD4300400192 /* OLMKitGroupTests.m */,
|
32A151301DABDD4300400192 /* OLMKitGroupTests.m */,
|
||||||
|
@ -282,6 +285,7 @@
|
||||||
buildActionMask = 2147483647;
|
buildActionMask = 2147483647;
|
||||||
files = (
|
files = (
|
||||||
3274F6071D9A633A005282E4 /* OLMKitTests.m in Sources */,
|
3274F6071D9A633A005282E4 /* OLMKitTests.m in Sources */,
|
||||||
|
32F143AF2236B4100077CF37 /* OLMKitSASTests.m in Sources */,
|
||||||
3244277D2175EF700023EDF1 /* OLMKitPkTests.m in Sources */,
|
3244277D2175EF700023EDF1 /* OLMKitPkTests.m in Sources */,
|
||||||
32A151311DABDD4300400192 /* OLMKitGroupTests.m in Sources */,
|
32A151311DABDD4300400192 /* OLMKitGroupTests.m in Sources */,
|
||||||
);
|
);
|
||||||
|
|
|
@ -28,6 +28,7 @@
|
||||||
#import <OLMKit/OLMOutboundGroupSession.h>
|
#import <OLMKit/OLMOutboundGroupSession.h>
|
||||||
#import <OLMKit/OLMPkEncryption.h>
|
#import <OLMKit/OLMPkEncryption.h>
|
||||||
#import <OLMKit/OLMPkDecryption.h>
|
#import <OLMKit/OLMPkDecryption.h>
|
||||||
|
#import <OLMKit/OLMSAS.h>
|
||||||
|
|
||||||
@interface OLMKit : NSObject
|
@interface OLMKit : NSObject
|
||||||
|
|
||||||
|
|
59
xcode/OLMKit/OLMSAS.h
Normal file
59
xcode/OLMKit/OLMSAS.h
Normal file
|
@ -0,0 +1,59 @@
|
||||||
|
/*
|
||||||
|
Copyright 2019 New Vector Ltd
|
||||||
|
|
||||||
|
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.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#import <Foundation/Foundation.h>
|
||||||
|
|
||||||
|
NS_ASSUME_NONNULL_BEGIN
|
||||||
|
|
||||||
|
/**
|
||||||
|
Short Authentication String verification utility class.
|
||||||
|
*/
|
||||||
|
@interface OLMSAS : NSObject
|
||||||
|
|
||||||
|
/**
|
||||||
|
Get the public key of the SAS object.
|
||||||
|
*/
|
||||||
|
- (NSString * _Nullable)publicKey;
|
||||||
|
|
||||||
|
/**
|
||||||
|
Set the public key of other user.
|
||||||
|
|
||||||
|
@param theirPublicKey the other user's public key.
|
||||||
|
@return error the error if any.
|
||||||
|
*/
|
||||||
|
- (NSError* _Nullable)setTheirPublicKey:(NSString*)theirPublicKey;
|
||||||
|
|
||||||
|
/**
|
||||||
|
Generate bytes to use for the short authentication string.
|
||||||
|
|
||||||
|
@param info extra information to mix in when generating the bytes, as per the Matrix spec.
|
||||||
|
@param length the size of the output buffer. For hex-based SAS as in the Matrix spec, this will be 5.
|
||||||
|
@return generated bytes
|
||||||
|
*/
|
||||||
|
- (NSData *)generateBytes:(NSString*)info length:(NSUInteger)length;
|
||||||
|
|
||||||
|
/**
|
||||||
|
Generate a message authentication code (MAC) based on the shared secret.
|
||||||
|
|
||||||
|
@param input the message to produce the authentication code for.
|
||||||
|
@param info extra information to mix in when generating the MAC, as per the Matrix spec.
|
||||||
|
@param error the error if any.
|
||||||
|
@return the MAC.
|
||||||
|
*/
|
||||||
|
- (NSString *)calculateMac:(NSString*)input info:(NSString*)info error:(NSError* _Nullable *)error; // TODO: NSError?
|
||||||
|
|
||||||
|
@end
|
||||||
|
|
||||||
|
NS_ASSUME_NONNULL_END
|
140
xcode/OLMKit/OLMSAS.m
Normal file
140
xcode/OLMKit/OLMSAS.m
Normal file
|
@ -0,0 +1,140 @@
|
||||||
|
/*
|
||||||
|
Copyright 2018 New Vector Ltd
|
||||||
|
|
||||||
|
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.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#import "OLMSAS.h"
|
||||||
|
|
||||||
|
#include "olm/olm.h"
|
||||||
|
#include "olm/sas.h"
|
||||||
|
#include "OLMUtility.h"
|
||||||
|
|
||||||
|
@interface OLMSAS () {
|
||||||
|
void *olmSASbuffer;
|
||||||
|
OlmSAS *olmSAS;
|
||||||
|
}
|
||||||
|
@end
|
||||||
|
|
||||||
|
@implementation OLMSAS
|
||||||
|
|
||||||
|
- (void)dealloc {
|
||||||
|
olm_clear_sas(olmSAS);
|
||||||
|
free(olmSASbuffer);
|
||||||
|
}
|
||||||
|
|
||||||
|
- (instancetype)init {
|
||||||
|
self = [super init];
|
||||||
|
if (self) {
|
||||||
|
olmSASbuffer = malloc(olm_sas_size());
|
||||||
|
olmSAS = olm_sas(olmSASbuffer);
|
||||||
|
|
||||||
|
size_t randomLength = olm_create_sas_random_length(olmSAS);
|
||||||
|
NSMutableData *random = [OLMUtility randomBytesOfLength:randomLength];
|
||||||
|
if (!random) {
|
||||||
|
return nil;
|
||||||
|
}
|
||||||
|
|
||||||
|
olm_create_sas(olmSAS, random.mutableBytes, randomLength);
|
||||||
|
|
||||||
|
[random resetBytesInRange:NSMakeRange(0, randomLength)];
|
||||||
|
}
|
||||||
|
return self;
|
||||||
|
}
|
||||||
|
|
||||||
|
- (NSString * _Nullable)publicKey {
|
||||||
|
size_t publicKeyLength = olm_sas_pubkey_length(olmSAS);
|
||||||
|
NSMutableData *publicKeyData = [NSMutableData dataWithLength:publicKeyLength];
|
||||||
|
if (!publicKeyData) {
|
||||||
|
return nil;
|
||||||
|
}
|
||||||
|
|
||||||
|
size_t result = olm_sas_get_pubkey(olmSAS, publicKeyData.mutableBytes, publicKeyLength);
|
||||||
|
if (result == olm_error()) {
|
||||||
|
const char *olm_error = olm_sas_last_error(olmSAS);
|
||||||
|
NSLog(@"[OLMSAS] publicKey: olm_sas_get_pubkey error: %s", olm_error);
|
||||||
|
return nil;
|
||||||
|
}
|
||||||
|
|
||||||
|
NSString *publicKey = [[NSString alloc] initWithData:publicKeyData encoding:NSUTF8StringEncoding];
|
||||||
|
return publicKey;
|
||||||
|
}
|
||||||
|
|
||||||
|
- (NSError * _Nullable)setTheirPublicKey:(NSString*)theirPublicKey {
|
||||||
|
NSMutableData *theirPublicKeyData = [theirPublicKey dataUsingEncoding:NSUTF8StringEncoding].mutableCopy;
|
||||||
|
|
||||||
|
size_t result = olm_sas_set_their_key(olmSAS, theirPublicKeyData.mutableBytes, theirPublicKeyData.length);
|
||||||
|
if (result == olm_error()) {
|
||||||
|
const char *olm_error = olm_sas_last_error(olmSAS);
|
||||||
|
NSLog(@"[OLMSAS] setTheirPublicKey: olm_sas_set_their_key error: %s", olm_error);
|
||||||
|
|
||||||
|
NSString *errorString = [NSString stringWithUTF8String:olm_error];
|
||||||
|
if (olm_error && errorString) {
|
||||||
|
return [NSError errorWithDomain:OLMErrorDomain
|
||||||
|
code:0
|
||||||
|
userInfo:@{
|
||||||
|
NSLocalizedDescriptionKey: errorString,
|
||||||
|
NSLocalizedFailureReasonErrorKey: [NSString stringWithFormat:@"olm_sas_set_their_key error: %@", errorString]
|
||||||
|
}];
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
return nil;
|
||||||
|
}
|
||||||
|
|
||||||
|
- (NSData *)generateBytes:(NSString *)info length:(NSUInteger)length {
|
||||||
|
NSData *infoData = [info dataUsingEncoding:NSUTF8StringEncoding];
|
||||||
|
|
||||||
|
NSMutableData *bytes = [NSMutableData dataWithLength:length];
|
||||||
|
if (!bytes) {
|
||||||
|
return nil;
|
||||||
|
}
|
||||||
|
|
||||||
|
olm_sas_generate_bytes(olmSAS, infoData.bytes, infoData.length, bytes.mutableBytes, length);
|
||||||
|
return bytes;
|
||||||
|
}
|
||||||
|
|
||||||
|
- (NSString *)calculateMac:(NSString *)input info:(NSString *)info error:(NSError *__autoreleasing _Nullable *)error {
|
||||||
|
NSMutableData *inputData = [input dataUsingEncoding:NSUTF8StringEncoding].mutableCopy;
|
||||||
|
NSData *infoData = [info dataUsingEncoding:NSUTF8StringEncoding];
|
||||||
|
|
||||||
|
size_t macLength = olm_sas_mac_length(olmSAS);
|
||||||
|
NSMutableData *macData = [NSMutableData dataWithLength:macLength];
|
||||||
|
if (!macData) {
|
||||||
|
return nil;
|
||||||
|
}
|
||||||
|
|
||||||
|
size_t result = olm_sas_calculate_mac(olmSAS,
|
||||||
|
inputData.mutableBytes, inputData.length,
|
||||||
|
infoData.bytes, infoData.length,
|
||||||
|
macData.mutableBytes, macLength);
|
||||||
|
if (result == olm_error()) {
|
||||||
|
const char *olm_error = olm_sas_last_error(olmSAS);
|
||||||
|
NSLog(@"[OLMSAS] calculateMac: olm_sas_calculate_mac error: %s", olm_error);
|
||||||
|
|
||||||
|
NSString *errorString = [NSString stringWithUTF8String:olm_error];
|
||||||
|
if (error && olm_error && errorString) {
|
||||||
|
*error = [NSError errorWithDomain:OLMErrorDomain
|
||||||
|
code:0
|
||||||
|
userInfo:@{
|
||||||
|
NSLocalizedDescriptionKey: errorString,
|
||||||
|
NSLocalizedFailureReasonErrorKey: [NSString stringWithFormat:@"olm_sas_calculate_mac error: %@", errorString]
|
||||||
|
}];
|
||||||
|
}
|
||||||
|
return nil;
|
||||||
|
}
|
||||||
|
|
||||||
|
NSString *mac = [[NSString alloc] initWithData:macData encoding:NSUTF8StringEncoding];
|
||||||
|
return mac;
|
||||||
|
}
|
||||||
|
|
||||||
|
@end
|
69
xcode/OLMKitTests/OLMKitSASTests.m
Normal file
69
xcode/OLMKitTests/OLMKitSASTests.m
Normal file
|
@ -0,0 +1,69 @@
|
||||||
|
/*
|
||||||
|
Copyright 2019 New Vector Ltd
|
||||||
|
|
||||||
|
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.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#import <XCTest/XCTest.h>
|
||||||
|
#import <OLMKit/OLMKit.h>
|
||||||
|
|
||||||
|
@interface OLMKitSASTests : XCTestCase {
|
||||||
|
OLMSAS *alice;
|
||||||
|
OLMSAS *bob;
|
||||||
|
}
|
||||||
|
|
||||||
|
@end
|
||||||
|
|
||||||
|
@implementation OLMKitSASTests
|
||||||
|
|
||||||
|
- (void)setUp {
|
||||||
|
alice = [OLMSAS new];
|
||||||
|
bob = [OLMSAS new];
|
||||||
|
}
|
||||||
|
|
||||||
|
- (void)tearDown {
|
||||||
|
alice = nil;
|
||||||
|
bob = nil;
|
||||||
|
}
|
||||||
|
|
||||||
|
- (void)testSASRandomness
|
||||||
|
{
|
||||||
|
XCTAssertNotEqualObjects(alice.publicKey, bob.publicKey);
|
||||||
|
}
|
||||||
|
|
||||||
|
- (void)testSASBytesMatch {
|
||||||
|
[alice setTheirPublicKey:bob.publicKey];
|
||||||
|
[bob setTheirPublicKey:alice.publicKey];
|
||||||
|
|
||||||
|
NSString *sas = @"SAS";
|
||||||
|
NSUInteger length = 5;
|
||||||
|
|
||||||
|
XCTAssertEqualObjects([alice generateBytes:sas length:length],
|
||||||
|
[bob generateBytes:sas length:length]);
|
||||||
|
}
|
||||||
|
|
||||||
|
- (void)testMACsMatch {
|
||||||
|
[alice setTheirPublicKey:bob.publicKey];
|
||||||
|
[bob setTheirPublicKey:alice.publicKey];
|
||||||
|
|
||||||
|
NSString *string = @"test";
|
||||||
|
NSString *info = @"MAC";
|
||||||
|
|
||||||
|
NSError *aliceError, *bobError;
|
||||||
|
XCTAssertEqualObjects([alice calculateMac:string info:info error:&aliceError],
|
||||||
|
[bob calculateMac:string info:info error:&bobError]);
|
||||||
|
XCTAssertNil(aliceError);
|
||||||
|
XCTAssertNil(bobError);
|
||||||
|
}
|
||||||
|
|
||||||
|
@end
|
|
@ -1,9 +1,9 @@
|
||||||
PODS:
|
PODS:
|
||||||
- OLMKit (2.3.0):
|
- OLMKit (3.0.0):
|
||||||
- OLMKit/olmc (= 2.3.0)
|
- OLMKit/olmc (= 3.0.0)
|
||||||
- OLMKit/olmcpp (= 2.3.0)
|
- OLMKit/olmcpp (= 3.0.0)
|
||||||
- OLMKit/olmc (2.3.0)
|
- OLMKit/olmc (3.0.0)
|
||||||
- OLMKit/olmcpp (2.3.0)
|
- OLMKit/olmcpp (3.0.0)
|
||||||
|
|
||||||
DEPENDENCIES:
|
DEPENDENCIES:
|
||||||
- OLMKit (from `../OLMKit.podspec`)
|
- OLMKit (from `../OLMKit.podspec`)
|
||||||
|
@ -13,8 +13,8 @@ EXTERNAL SOURCES:
|
||||||
:path: "../OLMKit.podspec"
|
:path: "../OLMKit.podspec"
|
||||||
|
|
||||||
SPEC CHECKSUMS:
|
SPEC CHECKSUMS:
|
||||||
OLMKit: 6af55a19917c35f86df5198c213979ecdf8ba76e
|
OLMKit: 88eda69110489f817d59bcb4353b7c247570aa4f
|
||||||
|
|
||||||
PODFILE CHECKSUM: 4e261dae61d833ec5585ced2473023b98909fd35
|
PODFILE CHECKSUM: 4e261dae61d833ec5585ced2473023b98909fd35
|
||||||
|
|
||||||
COCOAPODS: 1.6.0.beta.2
|
COCOAPODS: 1.6.0
|
||||||
|
|
Loading…
Reference in a new issue