Hi Tom, I have reflected your two comments in the revision: https://tools.ietf.org/html/draft-ietf-i2nsf-consumer-facing-interface-dm-11
Please see my answers inline below. On Sat, Aug 29, 2020 at 1:31 AM tom petch <[email protected]> wrote: > On 28/08/2020 14:46, Mr. Jaehoon Paul Jeong wrote: > > Hi Tom, > > I have addressed all your comments in the following revision: > > > https://tools.ietf.org/html/draft-ietf-i2nsf-consumer-facing-interface-dm-10 > > > > Inline > > > > Here are my answers for your comments: > > > ------------------------------------------------------------------------------------ > > Some more minor tweaks > > s.5.1 /gorup/group/ > > => The replacement is done. > > > > YANG module > > > > WG Chairs are not usually listed in the module - they used to be > > => The information of WG Chairs is removed. > > > > description is a bit terse - some quote the Abstract > > => I have improved the descriptions in the YANG module. > > > > YARA, SNORT, SURICATA would benefit from references; they are not ones I > > see in TLS or SSH! > > => I have added the references to YARA, SNORT, and SURICATA. > > > > typedef time I see in RFC6991bis > > => I used typedef time in RFC6991bis. > > See my other note about importing from 6991-bis rather than from 6991 > => I replaced 6991 with 6991-bis. > > > > > does the ipv6 addresss ever need the interface? > > => Yes, the IPv6 address needs the CFI interface. > > I added an XML example using IPv6 addresses. > > > > start/end ipv4/ipv6 could do with a must end > start > > => I put a description that an IPv4/IPv6 start address is lower than > > an IPv4/IPv6 end address. > > > > "A range match for IPv4 addresses is provided. Note that the > > start IPv4 address must be lower than the end IPv4 address."; > > > > "A range match for IPv6 addresses is provided. Note that the > > start IPv6 address must be lower than the end IPv4 address."; > > > > geo-ip could do with a reference > > => I added a reference to geo-ip as follows. > > RFC8805: A Format for Self-Published IP Geolocation Feeds > > > > s.9.1 221.159 is not a documentation address - see RFC5737 > > => I used documentation addresses for IPv4 from RFC5737. > > I also used documentation addresses for IPv6 from RFC3849. > > good > > > > IESG often expect an ipv6 example alongside ipv4 > > => I added an XML example using IPv6 addresses in Figure 19. > > > > s.12 Registrant should be IESG > > => I modified the IANA considerations section such that Registrant is the > > IESG. > > > > prefix is not that of the module > > => I am not sure of this comment. I think we use the correct prefix of > > "cfi-policy". > > CFI stands for Consumer-Facing Interface. > > Yes indeed you do - my mistake. What I had intended to say, looking at > other NSF modules, was that there are a number of NSF modules and the > chosen prefix have nothing in common. Bear in mind that all the YANG > modules get mixed up together on the box so while the prefix need to be > compact, there is something to be said for them to be meaningful so > RTGWG modules could start rt... or MPLS ones mpls... or PCE ones pce.. > and so on so you could consider using a prefix of nsf... such as nsfcfi > or if there are several such nsfcfi-p or some such (but that is getting > a bit long) > => I used nsfcfi for the prefix for Consumer-Facing Interface (CFI). Thanks. Best Regards, Paul > > Tom Petch > > > > ------------------------------------------------------------------------------------ > > > > Thanks for your valuable comments. > > > > Best Regards, > > Paul > > > > On Fri, Jul 17, 2020 at 8:07 PM tom petch <[email protected]> > wrote: > > > >> On 17/07/2020 10:51, tom petch wrote: > >>> On 11/07/2020 08:44, Mr. Jaehoon Paul Jeong wrote: > >>>> Hi Jan and Tom, > >>>> I have revised our I2NSF Consumer-Facing Interface (CFI) Data Model > >> Draft > >>>> according to both your comments. > >>>> > >>>> Jan, > >>>> I attach the revised draft and the revision letter to explain how I > have > >>>> reflected your comments one by one. > >>>> > >>>> Tom, > >>>> the references to RFC inside our YANG module cannot be cited in my I-D > >>>> XML > >>>> file, so I cannot include them > >>>> in Normative References. > >>> > >>> Yes you can and in fact you must:-) > >>> You can put anything you want to in Normative References with a > >>> corresponding [RFC0913] in the text part of the I-D so you add Section > >>> 8.1 "This YANG module imports from [RFC6991], ... and makes reference > to > >>> [RFC0854], [RFC0913], ......" > >>> > >>> Note that all import must have a reference clause and the referenced > >>> work must appear in Normative References; same technique applies. > >> > >> Some more minor tweaks > >> > >> s.5.1 /gorup/group/ > >> > >> YANG module > >> > >> WG Chairs are not usually listed in the module - they used to be > >> > >> descripton is a bit terse - some quote the Abstract > >> > >> YARA, SNORT, SURICATA would benefit from references; they are not ones I > >> see in TLS or SSH! > >> > >> typedef time I see in RFC6991bis > >> > >> does the ipv6 addresss ever need the interface? > >> > >> start/end ipv4/ipv6 could do with a must end > start > >> > >> geo-ip could do with a reference > >> > >> s.9.1 221.159 is not a documentation address - see RFC5737 > >> > >> IESG often expect an ipv6 example alongside ipv4 > >> > >> s.12 Registrant should be IESG > >> > >> prefix is not that of the module > >> > >> > >> Tom Petch > >> > >> > >>> Tom Petch > >>> > >>>> > >>>> Also, the choice of the prefix is i2nsf-cfi. > >>>> > >>>> I put "Note: This section is informative" for Sections 7 and 10, which > >>>> include XML configuration examples. > >>>> > >>>> If you have further comments, please let me know by July 12, 2020, in > >>>> EST. > >>>> If possible, I want to post this revision on July 13, 2020 after > >>>> reflecting > >>>> your further comments on the revision. > >>>> > >>>> Thanks. > >>>> > >>>> Paul > >>>> > >>>> > >>>> On Fri, Mar 20, 2020 at 2:25 AM Jan Lindblad <[email protected]> wrote: > >>>> > >>>>> Paul, > >>>>> > >>>>> Thank you for all your work with the module, and for the reminder for > >> me > >>>>> to verify all the changes. > >>>>> > >>>>> I am afraid I think the module is still not ready for last call, even > >> if > >>>>> it is better shape than ever thanks to your efforts. I went through > the > >>>>> module from top to bottom, so this is sorted in order of appearance. > >>>>> > >>>>> Line 107-204: The following identities are declared in the module, > but > >>>>> never referenced. They should either have a common base with > >>>>> something, or > >>>>> be referenced somewhere. If not, why are they defined here? They > >>>>> currently > >>>>> serve no purpose in this YANG module. > >>>>> identity ddos { > >>>>> identity enforce-type { > >>>>> identity admin { > >>>>> identity time { > >>>>> > >>>>> Line 377: Defining a custom date-and-time type seems odd. You should > >>>>> probably use one that has already been defined > >>>>> typedef date-and-time { > >>>>> > >>>>> Line 513: The leaf represents the name of a user, but the format is > >>>>> undefined. What should be the format for the string value? How would > >>>>> a user > >>>>> know what to configure here? Email addresses? If implementation > >>>>> dependent, > >>>>> say so. > >>>>> leaf name { > >>>>> type string; > >>>>> description > >>>>> "This represents the name of a user."; > >>>>> > >>>>> Line 518: If no IP address information is specified for the > user-group, > >>>>> what happens then? Is the user access accepted, rejected, or > >>>>> something else? > >>>>> uses ip-address-info; > >>>>> > >>>>> Line 658: Key leaf declared mandatory. All keys are mandatory, so > >>>>> mandatory is not needed on this leaf. > >>>>> leaf policy-name { > >>>>> type string; > >>>>> mandatory true; > >>>>> > >>>>> Line 664: Users mentioned in the owners-ref should have full CRUD > >>>>> privileges to the policy. But what about everyone else? Should they > >> have > >>>>> R(ead) privileges? Can anyone create new policies? If not, who can? > If > >>>>> someone creates a policy, but does not mention his own name among > >> owners > >>>>> (e.g. misspells or does not get the format right), he will not be > >>>>> able to > >>>>> modify or remove the policy. If no owner is mentioned, then noone > can. > >>>>> uses owners-ref; > >>>>> > >>>>> Line 673: Key leaf declared mandatory. All keys are mandatory, so > >>>>> mandatory is not needed on this leaf. > >>>>> leaf rule-name { > >>>>> type string; > >>>>> mandatory true; > >>>>> > >>>>> Line 682: Users mentioned in the owners-ref should have full CRUD > >>>>> privileges to the rule. But what about everyone else? Should they > have > >>>>> R(ead) privileges? Can anyone create new rules, or only those that > have > >>>>> full CRUD privileges for the policy? If someone creates a rule, but > >> does > >>>>> not mention his own name among owners (e.g. misspells or does not get > >>>>> the > >>>>> format right), he will not be able to modify or remove the rule. > >>>>> uses owners-ref; > >>>>> > >>>>> Line 697: Choice enforce-type has a description that I can't > >> understand. > >>>>> What does this mean? > >>>>> choice enforce-type { > >>>>> description > >>>>> "There are two different enforcement types; > >>>>> admin, and time. > >>>>> It cannot be allowed to configure > >>>>> admin=='time' or enforce-time=='admin'."; > >>>>> > >>>>> Line 703: In case of enforce-type admin (whatever that means), a > string > >>>>> value needs to be configured. What are the valid values for this > leaf? > >>>>> case enforce-admin { > >>>>> leaf admin { > >>>>> type string; > >>>>> description > >>>>> "This represents the enforcement type > >>>>> based on admin's decision."; > >>>>> > >>>>> Line 711: In case of enforce-type time, three times can be > configured. > >>>>> What is the relation between enforce-time, and the other two > >>>>> (begin-time, > >>>>> end-time)? > >>>>> case time { > >>>>> container time-information { > >>>>> description > >>>>> "The begin-time and end-time information > >>>>> when the security rule should be applied."; > >>>>> leaf enforce-time { > >>>>> type date-and-time; > >>>>> description > >>>>> "The enforcement type is time-enforced."; > >>>>> } > >>>>> leaf begin-time { > >>>>> type date-and-time; > >>>>> description > >>>>> "This is start time for time zone"; > >>>>> } > >>>>> leaf end-time { > >>>>> type date-and-time; > >>>>> description > >>>>> "This is end time for time zone"; > >>>>> } > >>>>> > >>>>> Furthermore, the locally defined date-and-time type used includes > both > >> a > >>>>> date and time, which seems to be at odds with the example > >>>>> configurations in > >>>>> the draft. Example 9.2: > >>>>> <rules> > >>>>> <rule> > >>>>> > <rule-name>block_access_to_sns_during_office_hours</rule-name> > >>>>> <event> > >>>>> <time-information> > >>>>> <begin-time>2020-03-11T09:00:00.00Z</begin-time> > >>>>> <end-time>2020-03-11T18:00:00.00Z</end-time> > >>>>> > >>>>> In the example, the rule-name > "block_access_to_sns_during_office_hours > >> " > >>>>> suggests that the begin-time and end-time should be times of day > >> between > >>>>> which the policy should be enforced. E.g. every day between 9.00 and > >>>>> 18.00. > >>>>> If that is a valid use case, using a time type with a date doesn't > make > >>>>> much sense. In the context of the policy that repeats "daily", how > >>>>> should > >>>>> the start date-and-time value "2020-03-11T09:00:00.00Z " be > >> interpreted? > >>>>> What if it was "monthly"? > >>>>> > >>>>> Line 736: In the frequency leaf, the enumeration value only-once is > for > >>>>> rules that don't repeat. But how long do they apply? A single > packet? A > >>>>> single time the rule is triggered? How does a user know if the rule > is > >>>>> still in effect, i.e. if the "once" has happened or not? > >>>>> enum only-once { > >>>>> > >>>>> Line 835: Maybe it's just my limited understanding of how > threat-feeds > >>>>> work, but I wonder i this construct with source and destinations for > >>>>> threat > >>>>> feeds is meaningful? > >>>>> container threat-feed-condition { > >>>>> description > >>>>> "The condition based on the threat-feed > information."; > >>>>> leaf-list source { > >>>>> type leafref { > >>>>> path > >>>>> "/i2nsf-cfi-policy/threat-preventions/threat-feed-list/name"; > >>>>> } > >>>>> description > >>>>> "Describes the threat-feed condition source."; > >>>>> } > >>>>> leaf dest-target { > >>>>> type leafref { > >>>>> path > >>>>> "/i2nsf-cfi-policy/threat-preventions/threat-feed-list/name"; > >>>>> } > >>>>> description > >>>>> "Describes the threat-feed condition destination."; > >>>>> > >>>>> Line 920: Location groups can be configured, but there seems to be no > >>>>> references to them. How are they supposed to be used? > >>>>> list location-group{ > >>>>> key "name"; > >>>>> uses location-group; > >>>>> > >>>>> Line 931: Regarding point 16.1 in your revision letter, you say "We > >>>>> think > >>>>> list type of threat-feed-list can be configured more than one feed of > >>>>> the > >>>>> same type". I'm afraid that is not the case with the current YANG > >>>>> model. If > >>>>> you do wish to allow more than one threat-feed-list for the same > >>>>> threat-feed-type, you need to add an additional key to your > >>>>> threat-feed-list. > >>>>> list threat-feed-list { > >>>>> key "name"; > >>>>> description > >>>>> "There can be a single or multiple number of > >>>>> threat-feeds."; > >>>>> uses threat-feed-info; > >>>>> > >>>>> ... > >>>>> grouping threat-feed-info { > >>>>> description > >>>>> "This is the grouping for the threat-feed-list"; > >>>>> leaf name { > >>>>> type identityref { > >>>>> base threat-feed-type; > >>>>> > >>>>> > >>>>> Generally, the indentation in the module is much improved. Some lines > >>>>> are > >>>>> still a bit off, however, so I would recommend using a tool that > >> indents > >>>>> consistently. > >>>>> > >>>>> Generally, I also wonder whether there has been any discussion with > >>>>> implementors around the admin security model proposed here. As noted > >>>>> before, it's a bit different from everything else I have seen. Is it > >>>>> well > >>>>> thought through? Do implementors feel this is doable and user > friendly? > >>>>> Currently there are no examples involving owner. Perhaps an example > >> that > >>>>> sheds some light over how different users create, modify and see the > >>>>> various rules would shed some light over this. > >>>>> > >>>>> Best Regards, > >>>>> /jan > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> > >>>>> On 18 Mar 2020, at 18:41, Mr. Jaehoon Paul Jeong > >>>>> <[email protected]> > >>>>> wrote: > >>>>> > >>>>> Hi Jan, > >>>>> Could you update the state of YANGDOCTORS Last Call Review on > >>>>> I2NSF Consumer-Facing Interface YANG Data Model if the updates are > >> fine > >>>>> to you? > >>>>> > >>>>> > >>>>> > >> > https://datatracker.ietf.org/doc/draft-ietf-i2nsf-consumer-facing-interface-dm/ > >>>>> > >>>>> > >>>>> I think your comments are all addressed in this version. > >>>>> > >>>>> Thanks. > >>>>> > >>>>> Best Regards, > >>>>> Paul > >>>>> > >>>>> On Thu, Mar 12, 2020 at 1:15 AM Mr. Jaehoon Paul Jeong < > >>>>> [email protected]> wrote: > >>>>> > >>>>>> Hi Jan, > >>>>>> We authors have addressed your comments with the revision: > >>>>>> > >>>>>> > >> > https://tools.ietf.org/html/draft-ietf-i2nsf-consumer-facing-interface-dm-08 > >>>>>> > >>>>>> > >>>>>> I attach a revision letter to explain how to respond to your > comments. > >>>>>> > >>>>>> If you have further comments, please let me know. > >>>>>> > >>>>>> Thanks. > >>>>>> > >>>>>> Best Regards, > >>>>>> Paul > >>>>>> > >>>>>> On Tue, Nov 12, 2019 at 1:53 AM Jan Lindblad via Datatracker < > >>>>>> [email protected]> wrote: > >>>>>> > >>>>>>> Reviewer: Jan Lindblad > >>>>>>> Review result: Almost Ready > >>>>>>> > >>>>>>> This is my YD review of > >>>>>>> draft-ietf-i2nsf-consumer-facing-interface-dm-07. I > >>>>>>> have previously reviewed the -05 revision (~end June). I find the > new > >>>>>>> revision > >>>>>>> much improved, but still with much to discuss. I will call this > >>>>>>> "almost > >>>>>>> ready". > >>>>>>> > >>>>>>> Generally speaking, I think the YANG module lacks the precision and > >>>>>>> descriptions needed to foster interoperability. The examples at the > >>>>>>> end > >>>>>>> are > >>>>>>> very enlightening however, and compensate for much of that, but > their > >>>>>>> informal > >>>>>>> nature can never replace proper YANG. The module usage needs to be > >>>>>>> mostly clear > >>>>>>> from the module itself. > >>>>>>> > >>>>>>> The management access control model proposed here is, even with its > >>>>>>> latest > >>>>>>> adaptation towards NACM, is still quite different from NACM > author's > >>>>>>> original > >>>>>>> ideas. I will therefore bring this use case up in the NETMOD WG for > >>>>>>> discussion. > >>>>>>> > >>>>>>> 1. Network access control principles > >>>>>>> > >>>>>>> Network access control is about which users are able to use the > >>>>>>> network > >>>>>>> being > >>>>>>> managed, for example connect to facebook. The purpose of the NSF > >>>>>>> module > >>>>>>> is to > >>>>>>> control this access. This version of the YANG module is now based > on > >> a > >>>>>>> list of > >>>>>>> policies. > >>>>>>> > >>>>>>> Each policy has a list of rules. Each rule has an event -- > >>>>>>> condition -- > >>>>>>> action > >>>>>>> triplet. This resembles traditional firewall management, which is a > >>>>>>> good > >>>>>>> thing, > >>>>>>> because that concept is stable and much tried. This allows > >>>>>>> operators to > >>>>>>> create > >>>>>>> lists of rules in this style: > >>>>>>> > >>>>>>> if pkt.x == 1: drop // Rule 1 > >>>>>>> elif pkt.y > 2: alert // Rule 2 > >>>>>>> elif pkt.z == 10: pass // Rule 3 > >>>>>>> else: drop // Rule 4 > >>>>>>> > >>>>>>> This pattern relies heavily on the ability to control the order of > >> the > >>>>>>> rules. > >>>>>>> The current model relies on the alphabetical sorting of names rules > >>>>>>> for > >>>>>>> the > >>>>>>> ordering. The YANG trick I would recommend to give operators the > >>>>>>> ability > >>>>>>> to > >>>>>>> insert and move rules as they wish is to add ordered-by user on the > >>>>>>> list: > >>>>>>> > >>>>>>> list rule { > >>>>>>> ordered-by user; // <== Add this line > >>>>>>> leaf rule-name { > >>>>>>> > >>>>>>> Nothing is said about what the system should do in case policies > >>>>>>> conflict. What > >>>>>>> if one policy says pass, the other drop for the same packet? Please > >>>>>>> clarify. > >>>>>>> What should happen to packets that do not match any of the > policies? > >>>>>>> > >>>>>>> This module also assumes that all users in the operator's > >> organization > >>>>>>> are > >>>>>>> listed in one or more NACM groups (e.g. "employees"). That wasn't > >>>>>>> really > >>>>>>> the > >>>>>>> NACM authors' original intent. Even if this could be made to work > >>>>>>> maybe, > >>>>>>> there > >>>>>>> is no strong reason to repurpose the NACM group concept for user > >>>>>>> network > >>>>>>> access > >>>>>>> purposes. It could easily be modeled differently. So in the cases > >>>>>>> where > >>>>>>> there > >>>>>>> are leafrefs to NACM groups when dealing with network access rather > >>>>>>> than > >>>>>>> management access, don't use NACM groups. > >>>>>>> > >>>>>>> leaf src-target { > >>>>>>> type leafref { > >>>>>>> path > >>>>>>> /nacm:nacm/nacm:groups/nacm:group/nacm:user-name; // > >>>>>>> <== Point to some other list of network users > >>>>>>> > >>>>>>> 2. Management access control principles > >>>>>>> > >>>>>>> Management access control is about which users are able to > >>>>>>> configure/run > >>>>>>> actions/the policies and rules. IMO, the most controversial aspect > of > >>>>>>> this > >>>>>>> module has always been its new and creative management access > control > >>>>>>> model. In > >>>>>>> this revision, the management principles have been remodeled > >>>>>>> greatly to > >>>>>>> fit in > >>>>>>> with NACM. I find this redesign very promising, but the result is > >>>>>>> still > >>>>>>> not > >>>>>>> quite ready for publication. > >>>>>>> > >>>>>>> The point where integration with NACM concepts is important is when > >> it > >>>>>>> comes to > >>>>>>> allow some users to CRUD the NSF policies and rules themselves. > >>>>>>> There is > >>>>>>> now a > >>>>>>> leaf-list "owners" on each policy and rule which point to a list of > >>>>>>> NACM > >>>>>>> groups. My understanding is that the idea is that the NSF module > >>>>>>> should > >>>>>>> be seen > >>>>>>> as a service model that translate high level ownership information > to > >>>>>>> specific > >>>>>>> NACM rules. It would be good to mention these ideas somewhere in > >>>>>>> the NSF > >>>>>>> document. > >>>>>>> > >>>>>>> leaf-list owners { > >>>>>>> type leafref { > >>>>>>> path /nacm:nacm/nacm:groups/nacm:group/nacm:name; > >>>>>>> > >>>>>>> I expect the intent is that any user listed in a NACM group > >>>>>>> mentioned in > >>>>>>> the > >>>>>>> owners list would get full CRUD privileges for the contents of the > >>>>>>> rule > >>>>>>> the > >>>>>>> owners leaf sits on. That is never spelled out anywhere, however. > >>>>>>> > >>>>>>> It is a little less clear how leaf-list owners on policy objects > >>>>>>> should > >>>>>>> be > >>>>>>> handled. Should owners listed on a policy object get full CRUD > powers > >>>>>>> over the > >>>>>>> entire policy, including all the rules inside? Or would they need > >>>>>>> to be > >>>>>>> listed > >>>>>>> on the rules as well? Not clear. Is the intent that users not > >>>>>>> listed on > >>>>>>> the > >>>>>>> policy object are unable to create new rules, but to be able to > >> update > >>>>>>> rules > >>>>>>> they are listed as owners of, if any? > >>>>>>> > >>>>>>> Who is allowed to create new policy objects? Should users that are > >> not > >>>>>>> owners > >>>>>>> get read access to all the policies and rules? > >>>>>>> > >>>>>>> Finally, there is an "owner" leaf on each rule with an identityref > >>>>>>> allowing > >>>>>>> operators to configure a role name like dept-head or sec-admin. It > is > >>>>>>> marked > >>>>>>> mandatory, but never included in any of the examples at the end of > >> the > >>>>>>> document. This makes me think this may be a remnant from bygone > >>>>>>> times and > >>>>>>> should be removed from the YANG. If not, an explanation of how to > use > >>>>>>> this > >>>>>>> leaf, and how it interacts with "owners" needs to be added, and the > >>>>>>> examples > >>>>>>> updated. > >>>>>>> > >>>>>>> 3. leafrefs crosspointing between policy instances > >>>>>>> > >>>>>>> There are six leafrefs that point to various objects inside a > policy, > >>>>>>> e.g. a > >>>>>>> rule condition pointing to a device group name. None of them > restrict > >>>>>>> what can > >>>>>>> be pointed to so that only names within the current policy are > >>>>>>> valid. It > >>>>>>> is > >>>>>>> therefore possible to configure the name of a device group defined > >>>>>>> in a > >>>>>>> different policy. I suspect this is not the intention. In order to > >>>>>>> restrict the > >>>>>>> leafrefs to the same policy, the following predicate can be added: > >>>>>>> > >>>>>>> leaf-list src-target { > >>>>>>> type leafref { > >>>>>>> path > >>>>>>> > >>>>>>> > >> > "/i2nsf-cfi-policy[policy-name=current()/../../../../../policy-name]/endpoint-group/device-group/name"; > >>>>>>> > >>>>>>> // <== Add predicate > >>>>>>> > >>>>>>> 4. Mandatory to implement all events, conditions, actions > >>>>>>> > >>>>>>> Each rule is defined with a choice of different events (admin, > time), > >>>>>>> conditions (firewall, ddos, custom, threat-feed) and actions (pass, > >>>>>>> drop, > >>>>>>> alert, mirror, ...). Is the intent that all of these options should > >> be > >>>>>>> mandatory to implement? The current model requires this. Also, > >>>>>>> would it > >>>>>>> make > >>>>>>> sense to allow additional mechanisms here? If so, it may be good to > >>>>>>> explain to > >>>>>>> readers how the set of choices and identities can be extended by > >>>>>>> implementations. > >>>>>>> > >>>>>>> 5. Optional and mandatory elements > >>>>>>> > >>>>>>> In this revision of the module, 8 leafs have been marked > mandatory. A > >>>>>>> few of > >>>>>>> them are list keys, which are conventionally not marked mandatory, > >>>>>>> since > >>>>>>> list > >>>>>>> keys are always mandatory. A few others are skipped in the XML > >>>>>>> examples > >>>>>>> at the > >>>>>>> end of the NSF document, which makes me believe they might not > >>>>>>> really be > >>>>>>> mandatory after all. > >>>>>>> > >>>>>>> Three leafs have a default, but most leafs are left optional > >>>>>>> without any > >>>>>>> default. In many cases I think I understand what it means to not > set > >> a > >>>>>>> leaf, > >>>>>>> but with the ones listed here, I don't think it clear at all. > >>>>>>> Either add > >>>>>>> a > >>>>>>> default to make it clear, make them mandatory if they should be, or > >>>>>>> explain in > >>>>>>> the leaf description what happens if not set. > >>>>>>> > >>>>>>> 493: leaf-list name > >>>>>>> 513: leaf-list protocol > >>>>>>> 531: leaf geo-ip-ipv4 > >>>>>>> 541: leaf continent > >>>>>>> 562: leaf feed-server-ipv4 > >>>>>>> 585: leaf payload-description > >>>>>>> 590: leaf-list content > >>>>>>> 600: leaf-list owners > >>>>>>> 870: leaf method > >>>>>>> > >>>>>>> 6. Indentation > >>>>>>> > >>>>>>> The YANG indentation is mostly wrong. Run the YANG text through > >>>>>>> pyang or > >>>>>>> some > >>>>>>> other tool that can indent the content correctly before you put it > >>>>>>> into a > >>>>>>> document. > >>>>>>> > >>>>>>> 7. YANG element naming > >>>>>>> > >>>>>>> The YANG convention is to not have lists on the top level in the > YANG > >>>>>>> module, > >>>>>>> but to surround lists with a container. The surrounding container > >>>>>>> often > >>>>>>> has a > >>>>>>> name in the plural and the list in singluar, like this > >>>>>>> > >>>>>>> container interfaces { > >>>>>>> list interface { > >>>>>>> > >>>>>>> To better fit into the world of IETF YANG modules, I'd recommend > >>>>>>> turning > >>>>>>> the > >>>>>>> top level list i2nsf-cfi-policy into this instead: > >>>>>>> > >>>>>>> container i2nsf-cfi-policies { > >>>>>>> list policy { > >>>>>>> > >>>>>>> Further down, I would change container rule to rules: > >>>>>>> > >>>>>>> container rules { > >>>>>>> list rule { > >>>>>>> > >>>>>>> Finally, it is customary to not repeat the names of parent object > >>>>>>> in the > >>>>>>> names > >>>>>>> of elements. For example, in the following: > >>>>>>> > >>>>>>> list threat-feed-list > >>>>>>> leaf feed-name > >>>>>>> leaf feed-server-ipv4 > >>>>>>> leaf feed-server-ipv6 > >>>>>>> leaf feed-description > >>>>>>> > >>>>>>> all the leafs should normally not repeat "feed-". Just leaf name, > >> leaf > >>>>>>> server-ipv4, leaf server-ipv6, leaf description. There are many > more > >>>>>>> examples > >>>>>>> of this throughout the module. > >>>>>>> > >>>>>>> The condition choice has many containers with a single leaf inside > >>>>>>> (e.g. > >>>>>>> ddos-source). Their purpose is rather unclear to me. Remove? > >>>>>>> > >>>>>>> container ddos-source { > >>>>>>> description > >>>>>>> "This represents the source."; > >>>>>>> leaf-list src-target { > >>>>>>> > >>>>>>> Also, I find the name "src-target" rather confusing. How about > >>>>>>> "source"? > >>>>>>> > >>>>>>> 8. No date leaf > >>>>>>> > >>>>>>> The draft text near fig 2 talks about a date leaf. There is no date > >>>>>>> object in > >>>>>>> this revision of te YANG. > >>>>>>> > >>>>>>> "Date: Date when this object was created or last modified" > >>>>>>> > >>>>>>> 9. leaf owner > >>>>>>> > >>>>>>> Near fig.3 leaf Owner is mentioned. Is this leaf still current? > >>>>>>> > >>>>>>> "Owner: This field contains the onwer of the rule. For example, > >>>>>>> the person who created it, and eligible for > modifying > >>>>>>> it." > >>>>>>> > >>>>>>> 10. leaf packet-per-second > >>>>>>> > >>>>>>> This is now modeled as uint16. Is this future proof? Many packet > >> flows > >>>>>>> on the > >>>>>>> internet exceed 64k pps. > >>>>>>> > >>>>>>> 11. container custon-source > >>>>>>> > >>>>>>> Misspelled. Should be custom-source > >>>>>>> > >>>>>>> 12. identity ddos > >>>>>>> > >>>>>>> Is ddos a malware file-type? This is not exactly in line with my > >>>>>>> intuition. > >>>>>>> > >>>>>>> 13. identity protocol-type > >>>>>>> > >>>>>>> There are other modules that already define protocol-types. Would > >>>>>>> it be > >>>>>>> worth > >>>>>>> reusing one of them? > >>>>>>> > >>>>>>> 14. identity palo-alto > >>>>>>> > >>>>>>> Is it a good IETF practice to list vendor names in modules? Can we > >>>>>>> consider > >>>>>>> this a protocol name? Is there perhaps an RFC/specification name > >>>>>>> for it > >>>>>>> that we > >>>>>>> could reference instead? > >>>>>>> > >>>>>>> 15. grouping ipsec-based-method > >>>>>>> > >>>>>>> This grouping contains a list which allows listing none of, either > >>>>>>> of or > >>>>>>> both > >>>>>>> of ipsecike and ikeless. Are all valid configurations? > >>>>>>> > >>>>>>> 16. leaf feed-name > >>>>>>> > >>>>>>> This leaf is the key in a list, which makes it possible to have at > >>>>>>> most > >>>>>>> one > >>>>>>> feed of each type. If it would make sense to configure more than > one > >>>>>>> feed of > >>>>>>> the same type, the YANG needs to be updated here. > >>>>>>> > >>>>>>> 17. leaf-list content > >>>>>>> > >>>>>>> This leaflist is of type string. What is the format of this string? > >>>>>>> Does > >>>>>>> the > >>>>>>> name refer to something? > >>>>>>> > >>>>>>> 18. Event types > >>>>>>> > >>>>>>> container event has a choice between enforce-admin and time > >>>>>>> alternatives. Each > >>>>>>> of those choices have a leaf that allows the operator to configure > an > >>>>>>> identityref to an enforce-type value. What does that mean? What > >>>>>>> would it > >>>>>>> mean > >>>>>>> if an operator configured admin == 'time' (or enforce-time == > >>>>>>> 'admin')? > >>>>>>> > >>>>>>> 19. leaf begin-time, end-time > >>>>>>> > >>>>>>> >From the examples, it can be seen that these are meant to be a > >>>>>>> time of > >>>>>>> day > >>>>>>> values. Currently they are modeled as yang:date-and-time, which > means > >>>>>>> they are > >>>>>>> a concrete time a specific day, e.g. 2019-11-11T16:07. This needs > >>>>>>> to be > >>>>>>> changed > >>>>>>> in order to be what the modeler intended. Perhaps like this: > >>>>>>> > >>>>>>> typedef time-of-day { > >>>>>>> type string { > >>>>>>> pattern '(2[0-3]|[01]?[0-9]):[0-5][0-9]'; > >>>>>>> } > >>>>>>> } > >>>>>>> > >>>>>>> 20. leaf frequency > >>>>>>> > >>>>>>> This leaf is now modeled properly from a YANG perspective. But what > >>>>>>> does > >>>>>>> it > >>>>>>> mean? If this leaf is set to 'once-only', what exactly will happen > >>>>>>> only > >>>>>>> once? > >>>>>>> Please write a description that explains this. > >>>>>>> > >>>>>>> 21. Example in Fig.17 > >>>>>>> > >>>>>>> The example contains XML that refers to > "endpoint-group/user-group". > >>>>>>> There is > >>>>>>> no such element in the YANG. > >>>>>>> > >>>>>>> <endpoint-group > >>>>>>> xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy"> > >>>>>>> <user-group> > >>>>>>> > >>>>>>> Furthermore, there is nothing called range-ip-address, > >>>>>>> start-ip-address, > >>>>>>> end-ip-address. They are called range-ipv4-address, > >>>>>>> start-ipv4-address, > >>>>>>> end-ipv4-address. > >>>>>>> > >>>>>>> <range-ip-address> > >>>>>>> <start-ip-address>221.159.112.1</start-ip-address> > >>>>>>> <end-ip-address>221.159.112.90</end-ip-address> > >>>>>>> </range-ip-address> > >>>>>>> > >>>>>>> Finally, there must not be any xmlns attribute on an closing XML > >>>>>>> tag. So > >>>>>>> > >>>>>>> </endpoint-group > >>>>>>> xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy"> > >>>>>>> > >>>>>>> should be > >>>>>>> > >>>>>>> </endpoint-group> > >>>>>>> > >>>>>>> This happens in several of the examples. > >>>>>>> > >>>>>>> 22. Example in Fig.18 > >>>>>>> > >>>>>>> There is no element called policy any more. It's now > >> i2nsf-cfi-policy. > >>>>>>> > >>>>>>> <policy > >> xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy"> > >>>>>>> <policy-name>security_policy_for_blocking_sns</policy-name> > >>>>>>> > >>>>>>> The rules are modeled in a container and list, both by the name > >>>>>>> rule. So > >>>>>>> there > >>>>>>> needs to be two <rule> tags. > >>>>>>> > >>>>>>> <rule> > >>>>>>> > >> <rule-name>block_access_to_sns_during_office_hours</rule-name> > >>>>>>> > >>>>>>> The security-event element is marked mandatory in the YANG, but > >>>>>>> missing > >>>>>>> in the > >>>>>>> example. The times given below may be what is intended, but do not > >>>>>>> match > >>>>>>> the > >>>>>>> date format for the type used (which include a date, etc). > >>>>>>> > >>>>>>> <event> > >>>>>>> <time-information> > >>>>>>> <begin-time>09:00</begin-time> > >>>>>>> <end-time>18:00</end-time> > >>>>>>> </time-information> > >>>>>>> </event> > >>>>>>> > >>>>>>> Since the example is not mentioning leaf frequency, it will have > the > >>>>>>> value > >>>>>>> 'once-only'. Maybe explain what that means in the context of the > >>>>>>> example? > >>>>>>> > >>>>>>> The condition/firewall-condition says the src-target is mandatory > and > >>>>>>> dest-target optional, exactly like below. > >>>>>>> condition/custom-destination/dest-target is mandatory and > >>>>>>> src-target is > >>>>>>> optional, exactly like below. Is this pure luck, or is there a > >> logical > >>>>>>> explanation why exactly those should be mandatory, and the example > >> use > >>>>>>> precisely those? > >>>>>>> > >>>>>>> <condition> > >>>>>>> <firewall-condition> > >>>>>>> <source-target> > >>>>>>> <src-target>employees</src-target> > >>>>>>> </source-target> > >>>>>>> </firewall-condition> > >>>>>>> <custom-condition> > >>>>>>> <destination-target> > >>>>>>> <dest-target>sns-websites</dest-target> > >>>>>>> </destination-target> > >>>>>>> </custom-condition> > >>>>>>> > >>>>>>> The current YANG model does not allow setting both a > >>>>>>> firewall-condition > >>>>>>> and > >>>>>>> custom-condition. If that should be allowed, the model needs to > >>>>>>> change. > >>>>>>> Should > >>>>>>> it be possible to have multiple firewall- or other conditions? That > >> is > >>>>>>> not > >>>>>>> currently possible. > >>>>>>> > >>>>>>> This example leaves out the mandatory leaf owner. Is that a sign > >>>>>>> that it > >>>>>>> should > >>>>>>> not be mandatory, or perhaps not exist at all? > >>>>>>> > >>>>>>> 23. Example in Fig.19 > >>>>>>> > >>>>>>> This example lists a firewall-condition with no src-target, which > is > >>>>>>> mandatory. > >>>>>>> > >>>>>>> <firewall-condition> > >>>>>>> <destination-target> > >>>>>>> <dest-target>employees</dest-target> > >>>>>>> </destination-target> > >>>>>>> </firewall-condition> > >>>>>>> > >>>>>>> Under condition, there is a container rate-limit with a leaf > >>>>>>> packet-per-second. > >>>>>>> Is this a trigger value for the condition, or is it an actual limit > >>>>>>> that > >>>>>>> the > >>>>>>> system is expected to enforce? If it's a trigger, it may be good to > >>>>>>> find > >>>>>>> a > >>>>>>> clearer name. If it's enforced, it's placement under condition is > >>>>>>> deceiving. > >>>>>>> > >>>>>>> If a rule's action is set to 'rate-limit', to which rate will it be > >>>>>>> limited? > >>>>>>> > >>>>>>> 24. Security Considerations > >>>>>>> > >>>>>>> Section 10 in the NSF document under review is the Security > >>>>>>> Considerations. I > >>>>>>> think it would make sense to mention something about the management > >>>>>>> access > >>>>>>> control mechanism here, and its relation to NACM. > >>>>>>> > >>>>>>> (End of list) > >>>>>>> > >>>>>>> > >>>>>>> _______________________________________________ > >>>>>>> I2nsf mailing list > >>>>>>> [email protected] > >>>>>>> https://www.ietf.org/mailman/listinfo/i2nsf > >>>>>>> > >>>>>> > >>>>>> > >>>>>> -- > >>>>>> =========================== > >>>>>> Mr. Jaehoon (Paul) Jeong, Ph.D. > >>>>>> Associate Professor > >>>>>> Department of Software > >>>>>> Sungkyunkwan University > >>>>>> Office: +82-31-299-4957 > >>>>>> Email: [email protected], [email protected] > >>>>>> Personal Homepage: http://iotlab.skku.edu/people-jaehoon-jeong.php > >>>>>> <http://cpslab.skku.edu/people-jaehoon-jeong.php> > >>>>>> > >>>>> > >>>>> > >>>>> -- > >>>>> =========================== > >>>>> Mr. Jaehoon (Paul) Jeong, Ph.D. > >>>>> Associate Professor > >>>>> Department of Software > >>>>> Sungkyunkwan University > >>>>> Office: +82-31-299-4957 > >>>>> Email: [email protected], [email protected] > >>>>> Personal Homepage: http://iotlab.skku.edu/people-jaehoon-jeong.php > >>>>> <http://cpslab.skku.edu/people-jaehoon-jeong.php> > >>>>> > >>>>> > >>>>> > >>>> > >> > > > > > -- =========================== Mr. Jaehoon (Paul) Jeong, Ph.D. Associate Professor Department of Computer Science and Engineering Sungkyunkwan University Office: +82-31-299-4957 Email: [email protected], [email protected] Personal Homepage: http://iotlab.skku.edu/people-jaehoon-jeong.php <http://cpslab.skku.edu/people-jaehoon-jeong.php>
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