On 6/13/21 3:36 PM, Jim Klimov via Nut-upsdev wrote:> Haven't got many ideas on this today, preoccupied with other > house-work, but can share a couple :) > > Regarding two implementations - I believe NSS and OpenSSL are licensed > differently and/or are (initially were?) available non-overlapping on > different OSes. A quick googling now showed that they both were > actually provided under different licenses over different releases and > years. > > As long as NUT consumes "some way to secure the packets" and does not > really care what that way is, leaching onto one or another library was > a decent choice (and better than using just one and offering nothing > on platforms that do not support it). > > I *think* the different ways of configuration apply to some features > only supported by (integration with?) one of those libraries, but > can't vouch for that OTOH :) > > Regarding self-signed certs vs. private (corporate) CA vs. commercial > - technically they are all the same, politics and setup policies and > responsibilities differ. Back in my sys-admining days, we had a > private CA with in-house scripting for openssl for engineering gear > (UPSes, PDUs, IPMIs and equivalents) which gave some measure of > security (encrypted comms) for many devices with some ease of setup > (one cert - engCA - to add trust for in a browser or similar client). > > Having an easy self-signed secure setup for small deployments (e.g. > home LAN) is certainly a welcome bonus - when several computers are > protected by one UPS and one upsd, but I'd expect (maybe biased) that > any sort of small office or larger deployment with more than a couple > of NUT clients and/or servers would go for a centralized cert setup. > It is not too hard to conjure up, with many free and commercial tools > available to orchestrate depending on the scale they would need. > > As for listening on several interfaces and/or ports from a single upsd > instance, can't quickly check, so would fathom a guess that NUT > codebase did not have a reason to bother yet to support that. > Otherwise, your points (4) and (5) make sense and are "doable" > generally, after some effort :)1. There are miriad of scripts written on top of openssl and certutil that allow implementing a CA and issuance of certificates, with easy-rsa probably leading the lot (and usage basically consists of running ./build-ca followed by ./build-key ( for v2 ) and equivalent parameters passed to the only script that easy-rsa v3 consists of ). Even f-droid provides one for android, if I am not mistaken. I really do not see the need for yet another set of scripts that reimplement the wheel, especially as the existing programs provide a full stack of tools implementing all the stages a certificate can have, from creating a CA to revoking a certificate. 2. nut can be very nicely wrapped behind stunnel if a point to point connection between master and slaves is needed. Other tools also exist, are reliable and well known, tested and vetted. Therefore, from my point of view, even if the python shim approach is smart and nice, I do not see it as being really needed. A link to stunnel and an example included in the docs would do just as well. With all due respect, the shim idea looks to me like a "not invented here" approach. To be clear: I am not opposed to it but I would certainly not use it when "yum install stunnel / apt install stunnel" are available. 3. Last but not least, for anyone with low to moderate knowledge, letsencrypt takes minutes to setup and use and has the advantage of not requiring anything but running their script every 3 months. wolfy
Let's not overlook the simple fact that a lot of deployments are behind secure firewalls, on secure networks, and on servers and lans that no users have access to (physical ormotherwise), and thus have negligible security requirements beyond what the environment already provides. Yes, the more advanced stuff may have validity and use some places, but the ability to stand up nut without that added layer of complexity has a lot of value as well . . . (I run one of those environments, and frankly, would likely instantly cease to upgrade of all this was rammed down my throat and not a choice. The idiotic deliberate breakage of Java in that many older systems can no longer have a functional network console, even on a secure network, is the perfect example of what *NOT* to do!) The end user should *ALWAYS* have the choice - never a mandate! On June 13, 2021 11:06:35 AM CDT, Manuel Wolfshant <wolfy at nobugconsulting.ro> wrote:>On 6/13/21 3:36 PM, Jim Klimov via Nut-upsdev wrote: >> Haven't got many ideas on this today, preoccupied with other >> house-work, but can share a couple :) >> >> Regarding two implementations - I believe NSS and OpenSSL are licensed >> differently and/or are (initially were?) available non-overlapping on >> different OSes. A quick googling now showed that they both were >> actually provided under different licenses over different releases and >> years. >> >> As long as NUT consumes "some way to secure the packets" and does not >> really care what that way is, leaching onto one or another library was >> a decent choice (and better than using just one and offering nothing >> on platforms that do not support it). >> >> I *think* the different ways of configuration apply to some features >> only supported by (integration with?) one of those libraries, but >> can't vouch for that OTOH :) >> >> Regarding self-signed certs vs. private (corporate) CA vs. commercial >> - technically they are all the same, politics and setup policies and >> responsibilities differ. Back in my sys-admining days, we had a >> private CA with in-house scripting for openssl for engineering gear >> (UPSes, PDUs, IPMIs and equivalents) which gave some measure of >> security (encrypted comms) for many devices with some ease of setup >> (one cert - engCA - to add trust for in a browser or similar client). >> >> Having an easy self-signed secure setup for small deployments (e.g. >> home LAN) is certainly a welcome bonus - when several computers are >> protected by one UPS and one upsd, but I'd expect (maybe biased) that >> any sort of small office or larger deployment with more than a couple >> of NUT clients and/or servers would go for a centralized cert setup. >> It is not too hard to conjure up, with many free and commercial tools >> available to orchestrate depending on the scale they would need. >> >> As for listening on several interfaces and/or ports from a single upsd >> instance, can't quickly check, so would fathom a guess that NUT >> codebase did not have a reason to bother yet to support that. >> Otherwise, your points (4) and (5) make sense and are "doable" >> generally, after some effort :) > >1. There are miriad of scripts written on top of openssl and certutil >that allow implementing a CA and issuance of certificates, with easy-rsa >probably leading the lot (and usage basically consists of running >./build-ca followed by ./build-key ( for v2 ) and equivalent parameters >passed to the only script that easy-rsa v3 consists of ). Even f-droid >provides one for android, if I am not mistaken. I really do not see the >need for yet another set of scripts that reimplement the wheel, >especially as the existing programs provide a full stack of tools >implementing all the stages a certificate can have, from creating a CA >to revoking a certificate. > >2. nut can be very nicely wrapped behind stunnel if a point to point >connection between master and slaves is needed. Other tools also exist, >are reliable and well known, tested and vetted. Therefore, from my point >of view, even if the python shim approach is smart and nice, I do not >see it as being really needed. A link to stunnel and an example included >in the docs would do just as well. With all due respect, the shim idea >looks to me like a "not invented here" approach. To be clear: I am not >opposed to it but I would certainly not use it when "yum install stunnel >/ apt install stunnel" are available. > >3. Last but not least, for anyone with low to moderate knowledge, >letsencrypt takes minutes to setup and use and has the advantage of not >requiring anything but running their script every 3 months. > > >wolfy > > >_______________________________________________ >Nut-upsdev mailing list >Nut-upsdev at alioth-lists.debian.net >https://alioth-lists.debian.net/cgi-bin/mailman/listinfo/nut-upsdev-- Sent from my Android device with K-9 Mail. Please excuse my brevity. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://alioth-lists.debian.net/pipermail/nut-upsdev/attachments/20210613/a4291801/attachment-0002.htm>
On June 13, 2021 9:02:46 PM GMT+03:00, Tim Dawson <tadawson at tpcsvc.com> wrote:>Let's not overlook the simple fact that a lot of deployments are behind >secure firewalls, on secure networks, and on servers and lans that no >users have access to (physical ormotherwise), and thus have negligible >security requirements beyond what the environment already provides. >Yes, the more advanced stuff may have validity and use some places, but >the ability to stand up nut without that added layer of complexity has >a lot of value as well . . .Absolutely correct.> >(I run one of those environments, and frankly, would likely instantly >cease to upgrade of all this was rammed down my throat and not a >choice.Same here>The idiotic deliberate breakage of Java in that many older >systems can no longer have a functional network console, even on a >secure network, is the perfect example of what *NOT* to do!)Incidentally I fight for 2 weeks trying to obtain again control over an IBM chassis which requires an old Java> The end >user should *ALWAYS* have the choice - never a mandate! >My thoughts exactly ! Thank you for phrasing it out loud, Tim.> >On June 13, 2021 11:06:35 AM CDT, Manuel Wolfshant ><wolfy at nobugconsulting.ro> wrote: >>On 6/13/21 3:36 PM, Jim Klimov via Nut-upsdev wrote: >>> Haven't got many ideas on this today, preoccupied with other >>> house-work, but can share a couple :) >>> >>> Regarding two implementations - I believe NSS and OpenSSL are >licensed >>> differently and/or are (initially were?) available non-overlapping >on >>> different OSes. A quick googling now showed that they both were >>> actually provided under different licenses over different releases >and >>> years. >>> >>> As long as NUT consumes "some way to secure the packets" and does >not >>> really care what that way is, leaching onto one or another library >was >>> a decent choice (and better than using just one and offering nothing > >>> on platforms that do not support it). >>> >>> I *think* the different ways of configuration apply to some features > >>> only supported by (integration with?) one of those libraries, but >>> can't vouch for that OTOH :) >>> >>> Regarding self-signed certs vs. private (corporate) CA vs. >commercial >>> - technically they are all the same, politics and setup policies and > >>> responsibilities differ. Back in my sys-admining days, we had a >>> private CA with in-house scripting for openssl for engineering gear >>> (UPSes, PDUs, IPMIs and equivalents) which gave some measure of >>> security (encrypted comms) for many devices with some ease of setup >>> (one cert - engCA - to add trust for in a browser or similar >client). >>> >>> Having an easy self-signed secure setup for small deployments (e.g. >>> home LAN) is certainly a welcome bonus - when several computers are >>> protected by one UPS and one upsd, but I'd expect (maybe biased) >that >>> any sort of small office or larger deployment with more than a >couple >>> of NUT clients and/or servers would go for a centralized cert setup. > >>> It is not too hard to conjure up, with many free and commercial >tools >>> available to orchestrate depending on the scale they would need. >>> >>> As for listening on several interfaces and/or ports from a single >upsd >>> instance, can't quickly check, so would fathom a guess that NUT >>> codebase did not have a reason to bother yet to support that. >>> Otherwise, your points (4) and (5) make sense and are "doable" >>> generally, after some effort :) >> >>1. There are miriad of scripts written on top of openssl and certutil >>that allow implementing a CA and issuance of certificates, with >easy-rsa >>probably leading the lot (and usage basically consists of running >>./build-ca followed by ./build-key ( for v2 ) and equivalent >parameters >>passed to the only script that easy-rsa v3 consists of ). Even f-droid > >>provides one for android, if I am not mistaken. I really do not see >the >>need for yet another set of scripts that reimplement the wheel, >>especially as the existing programs provide a full stack of tools >>implementing all the stages a certificate can have, from creating a CA > >>to revoking a certificate. >> >>2. nut can be very nicely wrapped behind stunnel if a point to point >>connection between master and slaves is needed. Other tools also >exist, >>are reliable and well known, tested and vetted. Therefore, from my >point >>of view, even if the python shim approach is smart and nice, I do not >>see it as being really needed. A link to stunnel and an example >included >>in the docs would do just as well. With all due respect, the shim idea > >>looks to me like a "not invented here" approach. To be clear: I am not > >>opposed to it but I would certainly not use it when "yum install >stunnel >>/ apt install stunnel" are available. >> >>3. Last but not least, for anyone with low to moderate knowledge, >>letsencrypt takes minutes to setup and use and has the advantage of >not >>requiring anything but running their script every 3 months. >> >> >>wolfy
On Sun, 13 Jun 2021, Manuel Wolfshant wrote:> 1. There are miriad of scripts written on top of openssl and certutil that > allow implementing a CA and issuance of certificates, with easy-rsa probably > leading the lot ... > > 2. nut can be very nicely wrapped behind stunnel if a point to point > connection between master and slaves is needed. ... . Therefore, from my point > of view, even if the python shim approach is smart and nice, I do not see it > as being really needed.The I-D has to have a Security Considerations chapter, and that chapter has to talk about secure communication. The shims described in the I-D are a very simple, stand-alone solution, and the implementation in upsdTLS.py and upsmonTLS.py provides a demonstration of what the I-D says. Nothing in the I-D says you have to use them: stunnel should be seen as the equivalent of "shims".> A link to stunnel and an example included in the docs would do > just as well.A volunteer to write that doc step forwards! Is stunnel maintained? Their tutorial at https://www.stunnel.org/howto.html was last updated in August 2019, but it still talks about TCP wrappers for which the last stable release 7.6 was by Wietse Venema himself April 08, 1997.> With all due respect, the shim idea looks to me like a "not > invented here" approach. To be clear: I am not opposed to it but I would > certainly not use it when "yum install stunnel / apt install stunnel" are > available.I use the upsd shim to run my own upsmon which insists on TLS 1.3. Hopefully with the next release of NUT, it wont be needed.> 3. Last but not least, for anyone with low to moderate knowledge, letsencrypt > takes minutes to setup and use and has the advantage of not requiring > anything but running their script every 3 months.Never overestimate a client! I was called to a NUT installation which had just been hit by lightning. This was an expensive on-line model, but I couldn't find it. Q: Where is the UPS? A: We threw it away. Q: Why? A: It stopped working. Q: Did you try resetting the circuit breaker button? A: What button? Roger