Martin,
I am happy with the latest suggestions and the userAgent fields: app / tech / os
JG - I will go ahead and post draft-ietf-regext-login-security-01 with this
change.
JG – For the blocking and rate limiting, I believe that the existing “stat”
event type will serve the purpose.
I think draft-gould-casanova-regext-unhandled-namespaces would allow to put
loginSec:event in the <extValue> element analogous to the RGP example in
chapter 4.0 so when we are implementing loginSec we would do it in compliance
to the unhandled-namespaces in case the
urn:ietf:params:xml:ns:epp:loginSec-0.3 was not specified in <svcExtension>
<svcs>...
JG – Yes, draft-gould-casanova-regext-unhandled-namespaces can be used to
return the security event information to clients that don’t explicitly support
the urn:ietf:params:xml:ns:epp:loginSec-0.3 and now the
urn:ietf:params:xml:ns:epp:loginSec-0.4 namespaces. Below is an example of
returning the password expiry warning event using
draft-gould-casanova-regext-unhandled-namespaces.
<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
<response>
<result code="1000">
<msg>Command completed successfully</msg>
<extValue>
<value>
<loginSec:loginSecData
xmlns:loginSec=
"urn:ietf:params:xml:ns:epp:loginSec-0.4">
<loginSec:event
type="password"
level="warning"
exDate="2018-04-01T22:00:00.0Z"
lang="en">
Password expiration soon
</loginSec:event>
</loginSec:loginSecData>
</value>
<reason>
urn:ietf:params:xml:ns:epp:loginSec-0.4 not in login services
</reason>
</extValue>
</result>
<trID>
<clTRID>ABC-12345</clTRID>
<svTRID>54321-XYZ</svTRID>
</trID>
</response>
</epp>
—
JG
[cid:[email protected]]
James Gould
Distinguished Engineer
[email protected]
703-948-3271
12061 Bluemont Way
Reston, VA 20190
Verisign.com<http://verisigninc.com/>
From: regext <[email protected]> on behalf of Martin Casanova
<[email protected]>
Date: Tuesday, April 9, 2019 at 7:14 AM
To: "[email protected]" <[email protected]>
Subject: [EXTERNAL] Re: [regext] review of draft-ietf-regext-login-security-03
Jim
I am happy with the latest suggestions and the userAgent fields: app / tech / os
JG – Do you block the connection or new logins attempts? If it’s the ladder,
is there the need for a new Login Security event type to cover this use case?
Something like the following could be returned on a failed login response due
to a blocked client. I view the blocking as a separate security event from the
“stat” event type, since the “stat” event type is meant to be informative.
<loginSec:event
type=”blocked”
level=”error”
duration=”PT5M”>
Client login blocked for 5 more minutes
</loginSec:event>
MC - In fact we do disconnect the TLS connection immediately (without even
sending a greeting) if the client is in status BLOCKED.
But I was thinking it would maybe be interesting to the client that this
BLOCKED state occurred at the next successful login (which is only possible
after the BLOCKED period has expired).
Maybe there are similar mechanisms in place at other registries that prevent
brute force attacks on the credentials of registrars. I think this could be
handled with the existing stat event.
<loginSec:event
type="stat"
name="failed blocked"
level="warning"
value="x failed commands / y min"
duration="P1D">
Client has been blocked because of too many failed requests
</loginSec:event>
We also do have a rate limit in place that checks that clients only can send x
requests in y seconds... If the rate is exceeded for too long the response of
the current command is delayed x seconds (timeout)
and the new commands are not accepted anymore but answered right away with
<response>
<result code="2500">
<msg lang="en">Command failed; server closing connection</msg>
<extValue>
<value>
<epp />
</value>
<reason lang="en">Too many requests per second! Timeout ms.:
#####</reason>
</extValue>
</result>
<trID>
<dont_check>$dont_check$</dont_check>
</trID>
</response>
this could also result in a waring event at next login but the above response
gives already a hint:
<loginSec:event
type="stat"
name="quota timeout"
level="warning"
value="x commands / y min"
duration="P1D">
Quota was exceeded
</loginSec:event>
Do you have similar mechanisms in place ?
I think draft-gould-casanova-regext-unhandled-namespaces would allow to put
loginSec:event in the <extValue> element analogous to the RGP example in
chapter 4.0 so when we are implementing loginSec we would do it in compliance
to the unhandled-namespaces in case the
urn:ietf:params:xml:ns:epp:loginSec-0.3 was not specified in <svcExtension>
<svcs>...
Martin
On 08.04.19 15:23, Gould, James wrote:
Martin,
I include my comments embedded below.
—
JG
[cid:[email protected]]
James Gould
Distinguished Engineer
[email protected]
703-948-3271
12061 Bluemont Way
Reston, VA 20190
Verisign.com<http://verisigninc.com/>
From: Martin Casanova
<[email protected]><mailto:[email protected]>
Date: Monday, April 8, 2019 at 6:28 AM
To: James Gould <[email protected]><mailto:[email protected]>,
"[email protected]"<mailto:[email protected]>
<[email protected]><mailto:[email protected]>
Subject: [EXTERNAL] Re: [regext] review of draft-ietf-regext-login-security-03
Jim
Below my comments. Thanks.
MC
On 04.04.19 00:20, Gould, James wrote:
Martin,
Thank you for doing a detailed review of draft-ietf-regext-login-security. I
provide my responses to your feedback embedded below.
—
JG
[cid:[email protected]]
James Gould
Distinguished Engineer
[email protected]
703-948-3271
12061 Bluemont Way
Reston, VA 20190
Verisign.com<http://verisigninc.com/>
From: regext <[email protected]><mailto:[email protected]> on
behalf of Martin Casanova
<[email protected]><mailto:[email protected]>
Date: Tuesday, March 26, 2019 at 1:56 PM
To: "[email protected]"<mailto:[email protected]>
<[email protected]><mailto:[email protected]>
Subject: [EXTERNAL] [regext] review of draft-ietf-regext-login-security-03
Jim
Since we support that draft I started implementing and read it again more
carefully. I have the following comments / feedback
1. (comment) Event type "cipher" or "tlsProtocol" :
In case the client uses deprecated protocol or cipher we currently hang up the
TLS connection immediately so there is no possibility to send a type "error"
security event.
At chapter 3.1 near "exDate" is written that "At expiry there MAY be an error
to connect or MAY be an error to login." So in case of an error to connect you
run in the same situation and will not be able to send back a "error" level
event but thats OK. However it is useful to warn the client during a transition
period when we know that we are going to disable a certain cipher or TLS
protocol on a specific day in the future.
JG – Yes, connectivity events like “cipher”, “tlsProtocol”, and “certificate”
are really only useful when they are provided as a warning with an optional
exDate to indicate when the event will result in a connection error. The
policies for the possible set of events can be defined using the Login Security
Policy Extension
(https://tools.ietf.org/html/draft-gould-regext-login-security-policy), which
is an extension of the Registry Mapping
(https://tools.ietf.org/html/draft-gould-carney-regext-registry). The clients
need to look for the security events in the login response to act on them.
MC -Agreed.
2 . (comment) Event type “newPw”:
Here we currently use 2306 “Parameter value policy error” and write in the
<reason> of <extValue> element that the new password was too weak.
I guess we would use the loginSec Event in the future in case the extension was
specified at login whether the pw was changed via login-security extension or
not.
I know that you have foreseen draft-gould-regext-login-security-policy to query
about password complexity but I think for convenience of the registrar it would
still be nice to somehow include the password requirement in the response even
if it is redundant. Otherwise one has to implement
draft-gould-regext-login-security-policy at the same time or communicate the
requirement out of band.
Maybe like that
S: <loginSec:event
S: type=”newPW”
S: value=”expression:
(?=.*\d)(?=.*[a-zA-Z])(?=.*[\x21-\x2F\x3A-\x40\x5B-\x60\x7B-\x7E]) (?!^\s+)
(?!.*\s+$)(?!.*\s{2,})^[\x20-\x7e]{16,128}$”
S: level=”error”>
S: New password does not meet complexity requirements
S: </loginSec:event>
S: <result code=”2200”>
S: <msg>Authentication error</msg>
Are you sure you want to return a 2200 and not a 2306 Parameter value policy
error in this case (page 10). I don’t see a reason why this should be another
return code with or without extension.
JG – On the first part of your feedback, I’m not sure that we want to inject
policy elements into the error response. Of course the policy information
could be embedded within the human readable message, such as below. I don’t
recommend the client parsing the human readable message for policy information,
but this would be useful for logging and troubleshooting on the client-side.
One issue is that the client can only receive the password complexity
expression upon an error. It’s best to handle the password complexity
expression out-of-band or via the Login Security Policy Extension
(draft-gould-regext-login-security-policy) to enable the client to know about
the policy prior to an error.
S: <loginSec:event
S: type=”newPW”
S: level=”error”>
S: New password does not meet complexity requirement:
(?=.*\d)(?=.*[a-zA-Z])(?=.*[\x21-\x2F\x3A-\x40\x5B-\x60\x7B-\x7E]) (?!^\s+)
(?!.*\s+$)(?!.*\s{2,})^[\x20-\x7e]{16,128}$
S: </loginSec:event>
MC - agreed: - useful for logging and troubleshooting on the client-side,
shouldn't be parsed.. Generally I think error feedback should be as indicative
of the problem as possible so the registrar would not open a ticket at the
registry to ask why the error occurred or how it could be prevented. The out of
band documentation is a must anyway so these tickets will be answered by RTFM!
as in many cases :)
I guess this is a "nice to have" but I also don't see a problem with including
this piece of policy information. It's not a policy information that is
enforced by XML Schema or so..
JG – Inclusion of the password complexity policy can be included in the event
message as a “nice to have”, but I recommend that we leave this out of the
draft.
JG – On the second part of your feedback, I believe that the login should fail
if an invalid new password is passed with a 2200 “Authentication error”. The
use of 2200 is not normative, so the server could choose a different result
code, such as 2306. The Login Security Extension will provide more specific
information associated with the error. Are there thoughts from others related
to which error result code (2200, 2306, or other) should be used for an invalid
new password and whether it should be normative?
MC - RFC 5730
2200 "Authentication error"
This response code MUST be returned when a server notes an
error when validating client credentials.
So I think 2200 is OK if you see <newpw> already as client credentials. However
a client could get confused with 2200 thinking the error code relates to the
<pw> filed which is correct. (if it wasn't for the <loginSec:event>) What is
your current return code when pw complexity is not OK without using loginSec
extension ? Ours is 2306..
JG – If passing an invalid new password results in a failure of the login, then
we would return a 2200. Inclusion of the “newPw” Login Security Extension
event in the error response should help to clarify the cause of the 2200.
3. (question) Event type "stat" :
How often would you send back this event
<loginSec:event
type="stat"
name="failedLogins"
level="warning"
value="100"
duration="P1D">
Excessive invalid daily logins
</loginSec:event>
Only once with first successful login after the series of failed ones or for a
whole day ? I suggest one time with first successful login.
JG – My thought is that returning the statistical information should not be
stateful, so that means that the interval would be up to the server (e.g., for
a one day duration start calculating the statistic based on a start / end of
midnight UTC), but all applicable events would be returned in all login
responses. I do not recommend the server keeping track of which events have
been returned and which have not been returned. What are your thoughts on this?
MC - Agreed that this should not be stateful and I wouldn't want to persist
anything for this. Currently we have a mechanism in place that hangs up the
existing session and blocks new TLS sessions for x seconds when there were too
many failed request in the past y seconds. We do have a "sliding window"
algorithm in place to determine whether a client is currently blocked or nor
not. We could use the same to inform at every successful login that a blocking
event occurred in the last 24 hours (since now)
JG – Do you block the connection or new logins attempts? If it’s the ladder,
is there the need for a new Login Security event type to cover this use case?
Something like the following could be returned on a failed login response due
to a blocked client. I view the blocking as a separate security event from the
“stat” event type, since the “stat” event type is meant to be informative.
<loginSec:event
type=”blocked”
level=”error”
duration=”PT5M”>
Client login blocked for 5 more minutes
</loginSec:event>
4. (question) In chapter 4.1 EPP <login> Command is written
..
internal contiguous
whitespace that includes #x9 (tab), #xA (linefeed), #xD (carriage
return), and #x20 (space) is replaced with a single #x20 (space).
...
Since this is “normal” XML parsing behavior should there not be reference to
where this is described for general XML processing. (I don’t know where that
would be though)
JG – The choice was to directly include the definition within the draft in
place of referencing out. I’m not aware of an RFC that can be referenced for
the XML processing of an XML schema “token” type. My recommendation is to
leave the definition directly in the draft without an external reference.
MC – OK
5. (suggestion) The element <loginSec:userAgent> could be more structured to
make it easier for the registry to parse the different fields and to give a
hint to the registrar what information should be provided.
Therefore I suggest child elements for example
<os> Operating System
<client> Client technology (eg. Java)
<version> Client software version (eg. 1.8.0) etc.
JG – If we were going to make the <loginSec:userAgent> structured, my
recommendation is to handle it with the following definition:
<complexType name=”userAgentType”>
<sequence>
<element name=”client” type=”token”
minOccurs=”0”/>
<element name=”lang” type=”token”
minOccurs=”0”/>
<element name=”os” type=”token”
minOccurs=”0”/>
</sequence>
</complexType>
JG – Below would be an example structured <loginSec:userAgent> element:
<loginSec:userAgent>
<loginSec:client>EPP SDK 1.0.0</loginSec:client>
<loginSec:lang>Java 11.0.2</loginSec:lang>
<loginSec:os>x86_64 Mac OS X 10.21</loginSec:os>
</loginSec:userAgent>
JG – What are your thoughts on the structured version of the
<loginSec:userAgent> element. If this works, I will revise the draft to
support it.
MC - Maybe the “lang” field is a bit misleading since “lang” also exists in
RFC 5730 where it has another meaning.
<element name=”lang” type=”language”
maxOccurs=”unbounded”/>
Hopefully nobody would fill it out with “EN”.. So maybe we could find another
terminology. How about “tec” for technology ?
The information that would be interesting to us is
- Client application and version (eg. EPP SDK 1.0.0)
- Client technology and version (eg. Openjdk version “1.8.0_191” or Perl or ?)
- Client OS and version (eg. Distributor ID: Ubuntu Description: Ubuntu
16.04.5 LTS))
So the version is important too to decide if a client is affected by some
security issues but maybe this would be an overkill to enforce / “ask for” or
not ?
JG – The <loginSec:client> element can be changed to the <loginSec:app>
element. To remove confusion for “lang”, how about changing the
<loginSec:lang> element to the <loginSec:tech> element. The description of the
app, tech, and os elements would encourage the inclusion of the version. The
following is the proposed description of the elements:
<loginSec:app>: OPTIONAL name of the client application software with
version if available, such as the name of the client SDK "EPP SDK 1.0.0".
<loginSec:tech>: OPTIONAL technology used for the client software with
version if available, such as "Java 11.0.2".
<loginSec:os>: OPTIONAL client operating system used with version if
available, such as "x86_64 Mac OS X 10.11.6"
The resulting <loginSec:userAgent> would be:
<loginSec:userAgent>
<loginSec:app>EPP SDK 1.0.0</loginSec:app>
<loginSec:tech>Java 11.0.2</loginSec:tech>
<loginSec:os>x86_64 Mac OS X 10.21</loginSec:os>
</loginSec:userAgent>
Does this work?
Other than that I have currently no feedback - so looking forward to the next
next revision..
Thanks
Martin Casanova
--
---
SWITCH
Martin Casanova, Domain Applications
Werdstrasse 2, P.O. Box, 8021 Zurich, Switzerland
phone +41 44 268 15 55, direct +41 44 268 16 25
[email protected]<mailto:[email protected]>,
www.switch.ch<http://www.switch.ch>
Working for a better digital world
--
---
SWITCH
Martin Casanova, Domain Applications
Werdstrasse 2, P.O. Box, 8021 Zurich, Switzerland
phone +41 44 268 15 55, direct +41 44 268 16 25
[email protected]<mailto:[email protected]>,
www.switch.ch<http://www.switch.ch>
Working for a better digital world
--
---
SWITCH
Martin Casanova, Domain Applications
Werdstrasse 2, P.O. Box, 8021 Zurich, Switzerland
phone +41 44 268 15 55, direct +41 44 268 16 25
[email protected]<mailto:[email protected]>,
www.switch.ch<http://www.switch.ch>
Working for a better digital world
_______________________________________________
regext mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/regext
