feat(core): Verify the server signature with SASL2

This commit is contained in:
PapaTutuWawa 2023-03-31 23:52:48 +02:00
parent 478b5b8770
commit f86dbe6af8
5 changed files with 222 additions and 10 deletions

View File

@ -134,7 +134,6 @@ abstract class XmppFeatureNegotiatorBase {
NegotiatorAttributes get attributes => _attributes;
/// Run after all negotiators are registered. Useful for registering callbacks against
/// other negotiators.
@visibleForOverriding
/// other negotiators. By default this function does nothing.
Future<void> postRegisterCallback() async {}
}

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@ -93,8 +93,9 @@ class SaslPlainNegotiator extends Sasl2AuthenticationNegotiator {
}
@override
Future<void> onSasl2Success(XMLNode response) async {
Future<Result<bool, NegotiatorError>> onSasl2Success(XMLNode response) async {
state = NegotiatorState.done;
return const Result(true);
}
@override

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@ -15,6 +15,18 @@ import 'package:moxxmpp/src/types/result.dart';
import 'package:random_string/random_string.dart';
import 'package:saslprep/saslprep.dart';
abstract class SaslScramError extends NegotiatorError {}
class NoAdditionalDataError extends SaslScramError {
@override
bool isRecoverable() => false;
}
class InvalidServerSignatureError extends SaslScramError {
@override
bool isRecoverable() => false;
}
// NOTE: Inspired by https://github.com/vukoye/xmpp_dart/blob/3b1a0588562b9e591488c99d834088391840911d/lib/src/features/sasl/ScramSaslHandler.dart
enum ScramHashType { sha1, sha256, sha512 }
@ -230,6 +242,12 @@ class SaslScramNegotiator extends Sasl2AuthenticationNegotiator {
return false;
}
bool _checkSignature(String base64Signature) {
final signature =
parseKeyValue(utf8.decode(base64.decode(base64Signature)));
return signature['v']! == _serverSignature;
}
@override
Future<Result<NegotiatorState, NegotiatorError>> negotiate(
XMLNode nonza,
@ -271,10 +289,7 @@ class SaslScramNegotiator extends Sasl2AuthenticationNegotiator {
);
}
// NOTE: This assumes that the string is always "v=..." and contains no other parameters
final signature =
parseKeyValue(utf8.decode(base64.decode(nonza.innerText())));
if (signature['v']! != _serverSignature) {
if (!_checkSignature(nonza.innerText())) {
// TODO(Unknown): Notify of a signature mismatch
//final error = nonza.children.first.tag;
//attributes.sendEvent(AuthenticationFailedEvent(error));
@ -329,13 +344,32 @@ class SaslScramNegotiator extends Sasl2AuthenticationNegotiator {
}
}
@override
Future<void> postRegisterCallback() async {
attributes
.getNegotiatorById<Sasl2Negotiator>(sasl2Negotiator)
?.registerSaslNegotiator(this);
}
@override
Future<List<XMLNode>> onSasl2FeaturesReceived(XMLNode sasl2Features) async {
return [];
}
@override
Future<void> onSasl2Success(XMLNode response) async {
Future<Result<bool, NegotiatorError>> onSasl2Success(XMLNode response) async {
// When we're done with SASL2, check the additional data to verify the server
// signature.
state = NegotiatorState.done;
final additionalData = response.firstTag('additional-data');
if (additionalData == null) {
return Result(NoAdditionalDataError());
}
if (!_checkSignature(additionalData.innerText())) {
return Result(InvalidServerSignatureError());
}
return const Result(true);
}
}

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@ -21,7 +21,7 @@ abstract class Sasl2FeatureNegotiator extends XmppFeatureNegotiatorBase {
/// Called by the SASL2 negotiator when the SASL2 negotiations are done. [response]
/// is the entire response nonza.
Future<void> onSasl2Success(XMLNode response);
Future<Result<bool, NegotiatorError>> onSasl2Success(XMLNode response);
}
/// A special type of [SaslNegotiator] that is aware of SASL2.
@ -184,13 +184,25 @@ class Sasl2Negotiator extends XmppFeatureNegotiatorBase {
if (nonza.tag == 'success') {
// Tell the dependent negotiators about the result
for (final negotiator in _featureNegotiators) {
await negotiator.onSasl2Success(nonza);
final result = await negotiator.onSasl2Success(nonza);
if (!result.isType<bool>()) {
return Result(result.get<NegotiatorError>());
}
}
// We're done
attributes.setAuthenticated();
attributes.removeNegotiatingFeature(saslXmlns);
return const Result(NegotiatorState.done);
} else if (nonza.tag == 'challenge') {
// We still have to negotiate
final challenge = nonza.innerText();
final response = XMLNode.xmlns(
tag: 'response',
xmlns: sasl2Xmlns,
text: await _currentSaslNegotiator!.getRawStep(challenge),
);
attributes.sendNonza(response);
}
}

View File

@ -74,6 +74,92 @@ void main() {
),
]);
final result = await conn.connect(
waitUntilLogin: true,
shouldReconnect: false,
enableReconnectOnSuccess: false,
);
expect(result.isType<NegotiatorError>(), false);
});
test('Test SCRAM-SHA-1 SASL2 negotiation with a valid signature', () async {
final fakeSocket = StubTCPSocket([
StringExpectation(
"<stream:stream xmlns='jabber:client' version='1.0' xmlns:stream='http://etherx.jabber.org/streams' to='server' xml:lang='en'>",
'''
<stream:stream
xmlns="jabber:client"
version="1.0"
xmlns:stream="http://etherx.jabber.org/streams"
from="server"
xml:lang="en">
<stream:features xmlns="http://etherx.jabber.org/streams">
<mechanisms xmlns="urn:ietf:params:xml:ns:xmpp-sasl">
<mechanism>PLAIN</mechanism>
<mechanism>SCRAM-SHA-256</mechanism>
</mechanisms>
<authentication xmlns='urn:xmpp:sasl:2'>
<mechanism>PLAIN</mechanism>
<mechanism>SCRAM-SHA-256</mechanism>
</authentication>
<bind xmlns="urn:ietf:params:xml:ns:xmpp-bind">
<required/>
</bind>
</stream:features>''',
),
StanzaExpectation(
"<authenticate xmlns='urn:xmpp:sasl:2' mechanism='SCRAM-SHA-256'><user-agent id='d4565fa7-4d72-4749-b3d3-740edbf87770'><software>moxxmpp</software><device>PapaTutuWawa's awesome device</device></user-agent><initial-response>biwsbj11c2VyLHI9ck9wck5HZndFYmVSV2diTkVrcU8=</initial-response></authenticate>",
'''
<challenge xmlns='urn:xmpp:sasl:2'>cj1yT3ByTkdmd0ViZVJXZ2JORWtxTyVodllEcFdVYTJSYVRDQWZ1eEZJbGopaE5sRiRrMCxzPVcyMlphSjBTTlk3c29Fc1VFamI2Z1E9PSxpPTQwOTY=</challenge>
''',
),
StanzaExpectation(
'<response xmlns="urn:xmpp:sasl:2">Yz1iaXdzLHI9ck9wck5HZndFYmVSV2diTkVrcU8laHZZRHBXVWEyUmFUQ0FmdXhGSWxqKWhObEYkazAscD1kSHpiWmFwV0lrNGpVaE4rVXRlOXl0YWc5empmTUhnc3FtbWl6N0FuZFZRPQ==</response>',
'<success xmlns="urn:xmpp:sasl:2"><additional-data>dj02cnJpVFJCaTIzV3BSUi93dHVwK21NaFVaVW4vZEI1bkxUSlJzamw5NUc0PQ==</additional-data><authorization-identifier>user@server</authorization-identifier></success>',
),
StanzaExpectation(
"<iq xmlns='jabber:client' type='set' id='aaaa'><bind xmlns='urn:ietf:params:xml:ns:xmpp-bind' /></iq>",
'''
'<iq xmlns="jabber:client" type="result" id="a"><bind xmlns="urn:ietf:params:xml:ns:xmpp-bind"><jid>polynomdivision@test.server/MU29eEZn</jid></bind></iq>',
''',
adjustId: true,
ignoreId: true,
),
]);
final conn = XmppConnection(
TestingReconnectionPolicy(),
AlwaysConnectedConnectivityManager(),
fakeSocket,
)..setConnectionSettings(
ConnectionSettings(
jid: JID.fromString('user@server'),
password: 'pencil',
useDirectTLS: true,
),
);
await conn.registerManagers([
PresenceManager(),
RosterManager(TestingRosterStateManager('', [])),
DiscoManager([]),
]);
await conn.registerFeatureNegotiators([
SaslPlainNegotiator(),
SaslScramNegotiator(
10,
'n=user,r=rOprNGfwEbeRWgbNEkqO',
'rOprNGfwEbeRWgbNEkqO',
ScramHashType.sha256,
),
ResourceBindingNegotiator(),
Sasl2Negotiator(
userAgent: const UserAgent(
id: 'd4565fa7-4d72-4749-b3d3-740edbf87770',
software: 'moxxmpp',
device: "PapaTutuWawa's awesome device",
),
),
]);
final result = await conn.connect(
waitUntilLogin: true,
shouldReconnect: false,
@ -81,4 +167,84 @@ void main() {
);
expect(result.isType<XmppError>(), false);
});
test('Test SCRAM-SHA-1 SASL2 negotiation with an invalid signature',
() async {
final fakeSocket = StubTCPSocket([
StringExpectation(
"<stream:stream xmlns='jabber:client' version='1.0' xmlns:stream='http://etherx.jabber.org/streams' to='server' xml:lang='en'>",
'''
<stream:stream
xmlns="jabber:client"
version="1.0"
xmlns:stream="http://etherx.jabber.org/streams"
from="server"
xml:lang="en">
<stream:features xmlns="http://etherx.jabber.org/streams">
<mechanisms xmlns="urn:ietf:params:xml:ns:xmpp-sasl">
<mechanism>PLAIN</mechanism>
<mechanism>SCRAM-SHA-256</mechanism>
</mechanisms>
<authentication xmlns='urn:xmpp:sasl:2'>
<mechanism>PLAIN</mechanism>
<mechanism>SCRAM-SHA-256</mechanism>
</authentication>
<bind xmlns="urn:ietf:params:xml:ns:xmpp-bind">
<required/>
</bind>
</stream:features>''',
),
StanzaExpectation(
"<authenticate xmlns='urn:xmpp:sasl:2' mechanism='SCRAM-SHA-256'><user-agent id='d4565fa7-4d72-4749-b3d3-740edbf87770'><software>moxxmpp</software><device>PapaTutuWawa's awesome device</device></user-agent><initial-response>biwsbj11c2VyLHI9ck9wck5HZndFYmVSV2diTkVrcU8=</initial-response></authenticate>",
'''
<challenge xmlns='urn:xmpp:sasl:2'>cj1yT3ByTkdmd0ViZVJXZ2JORWtxTyVodllEcFdVYTJSYVRDQWZ1eEZJbGopaE5sRiRrMCxzPVcyMlphSjBTTlk3c29Fc1VFamI2Z1E9PSxpPTQwOTY=</challenge>
''',
),
StanzaExpectation(
'<response xmlns="urn:xmpp:sasl:2">Yz1iaXdzLHI9ck9wck5HZndFYmVSV2diTkVrcU8laHZZRHBXVWEyUmFUQ0FmdXhGSWxqKWhObEYkazAscD1kSHpiWmFwV0lrNGpVaE4rVXRlOXl0YWc5empmTUhnc3FtbWl6N0FuZFZRPQ==</response>',
'<success xmlns="urn:xmpp:sasl:2"><additional-data>dj1zbUY5cHFWOFM3c3VBb1pXamE0ZEpSa0ZzS1E9</additional-data><authorization-identifier>user@server</authorization-identifier></success>',
),
]);
final conn = XmppConnection(
TestingReconnectionPolicy(),
AlwaysConnectedConnectivityManager(),
fakeSocket,
)..setConnectionSettings(
ConnectionSettings(
jid: JID.fromString('user@server'),
password: 'pencil',
useDirectTLS: true,
),
);
await conn.registerManagers([
PresenceManager(),
RosterManager(TestingRosterStateManager('', [])),
DiscoManager([]),
]);
await conn.registerFeatureNegotiators([
SaslPlainNegotiator(),
SaslScramNegotiator(
10,
'n=user,r=rOprNGfwEbeRWgbNEkqO',
'rOprNGfwEbeRWgbNEkqO',
ScramHashType.sha256,
),
ResourceBindingNegotiator(),
Sasl2Negotiator(
userAgent: const UserAgent(
id: 'd4565fa7-4d72-4749-b3d3-740edbf87770',
software: 'moxxmpp',
device: "PapaTutuWawa's awesome device",
),
),
]);
final result = await conn.connect(
waitUntilLogin: true,
shouldReconnect: false,
enableReconnectOnSuccess: false,
);
expect(result.isType<NegotiatorError>(), true);
expect(result.get<NegotiatorError>() is InvalidServerSignatureError, true);
});
}