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> ...when they do it should be domain/IP whitelisted only. In practice, this will work very poorly. Your whitelist will end up looking like "All of Azure, GCP,

> ...when they do it should be domain/IP whitelisted only. In practice, this will work very poorly. Your whitelist will end up looking like "All of Azure, GCP, AWS, and CloudFlare, plus some one-offs"... which doesn't really stop anything. I work at a BigCo that tries to do what you're proposing and it works so, so badly. Thankfully, we can turn off the "security" software that does this on our workstations. Unfortunately, cannot do the same for our software that runs on datacenter-hosted hardware that IT manages. > Clients shouldn't connect to the Internet by default... I have a couple of VLANs on my LAN that don't provide Internet access just for this reason.

fidotron 2y ago
> Your whitelist will end up looking like "All of Azure, GCP, AWS, and CloudFlare, plus some one-offs"... Why?
- simoncion 2y ago
  Because * A huge-ass slice of the things hosted on The Internet are hosted in or behind one or more of Azure, GCP, AWS, and CloudFlare. * Recording the set of "cloud provider"-provided IP addresses spoken to by a piece of client software is a bit of a fool's errand. The nature of those services is that one can change the IP address assigned to one's deployed software at a whim... and it's often cheaper to set things up so that one doesn't have an IP address for one's services that survives a VM reboot.
ndriscoll 2y ago
I think what's being said here is that if we're going to talk about what "needs" to be done about security (especially if government regulation is to be involved), and if we're going to ban something, then it ought to be devices that need to talk to "the cloud". Saying we "need" APs to segment VLANs is missing the point. The cloud servers are known to be malicious (e.g. that company that intentionally bricked people's inverters the other day). As you say, it's impossible to have reasonable filters when everything wants to talk to the entire world. What we "need" is for IoT devices to communicate through purely local networks and have no Internet access. e.g. mandate a standard to discover a local MQTT broker (which the router may also provide). In that world, there's no reason for a device to ever talk to anything other than e.g. 192.168.1.1, so filtering is easy and can be made default.
- simoncion 2y ago
  > The cloud servers are known to be malicious... Malicious software is malicious regardless of whether it's running as a VM on Someone Else's Server, or a Linux process on personally-owned bare metal. > Saying we "need" APs to segment VLANs is missing the point. > What we "need" is for IoT devices to communicate through purely local networks and have no Internet access. [They will do this via a mechanism using MQTT where they're required to declare if they're bad.] a) Who said anything about APs? While I do have WiFi Access Points (that I did not mention), I also have hard-wired VLAN segmentation. [0] b) From a network design perspective, it's a lot easier and more efficient to provide a VLAN that doesn't have Internet egress than to attempt to sort out which of a mess of hosts are permitted to talk to the Internet from which aren't, and ALSO prevent MAC- and/or IP-address spoofing to evade any such filtering. c) I have no idea why you're invoking MQTT (specifically), but any scheme that requires a potentially-untrusted host running potentially-untrusted hardware and software to declare whether or not it's to be trusted is doomed to failure right off the bat. [0] Sure, I'm a power user. But, a "VLAN-isolated network for untrusted machines" feature shouldn't be something that only power users get. This SHOULD be a baseline feature in consumer-grade WiFi APs and switches. (The race-to-the-bottom feature of the "market" for consumer gear is very sad.)
  - ndriscoll 2y ago
    Most people have a single combo box for their router/switch/firewall/AP, and maybe modem. For most people, those things are synonymous. The point is isolating devices from each other isn't what people need. They need their devices to accept commands from each other or their computer/phone. What they don't need is their devices to talk to half the Internet. My htpc talks to exactly one machine, for example (my NAS). It's trivial to audit and would work fine if I blocked Internet access or gave it a whitelist. For people that use home assistant, again their devices should need to talk to a broker and that's it. A reasonable device only talks to a handful of locations because you didn't ask it to do anything else. The world where Android and Windows and IoT devices chat all day to thousands of servers is what's the problem. Restricting such devices to only talk to the Internet is exactly the wrong solution. You could lock things down once there's an ecosystem in place for local control, but doing it now just ossifies the existing dumpster fire. If one were to suggest regulation is needed for security (and governments are starting to do so), then what's needed is to ban cloud devices.

fidotron 2y ago

> Your whitelist will end up looking like "All of Azure, GCP, AWS, and CloudFlare, plus some one-offs"... Why?

simoncion 2y ago
Because * A huge-ass slice of the things hosted on The Internet are hosted in or behind one or more of Azure, GCP, AWS, and CloudFlare. * Recording the set of "cloud provider"-provided IP addresses spoken to by a piece of client software is a bit of a fool's errand. The nature of those services is that one can change the IP address assigned to one's deployed software at a whim... and it's often cheaper to set things up so that one doesn't have an IP address for one's services that survives a VM reboot.

ndriscoll 2y ago

I think what's being said here is that if we're going to talk about what "needs" to be done about security (especially if government regulation is to be involved), and if we're going to ban something, then it ought to be devices that need to talk to "the cloud". Saying we "need" APs to segment VLANs is missing the point. The cloud servers are known to be malicious (e.g. that company that intentionally bricked people's inverters the other day). As you say, it's impossible to have reasonable filters when everything wants to talk to the entire world. What we "need" is for IoT devices to communicate through purely local networks and have no Internet access. e.g. mandate a standard to discover a local MQTT broker (which the router may also provide). In that world, there's no reason for a device to ever talk to anything other than e.g. 192.168.1.1, so filtering is easy and can be made default.

simoncion 2y ago
> The cloud servers are known to be malicious... Malicious software is malicious regardless of whether it's running as a VM on Someone Else's Server, or a Linux process on personally-owned bare metal. > Saying we "need" APs to segment VLANs is missing the point. > What we "need" is for IoT devices to communicate through purely local networks and have no Internet access. [They will do this via a mechanism using MQTT where they're required to declare if they're bad.] a) Who said anything about APs? While I do have WiFi Access Points (that I did not mention), I also have hard-wired VLAN segmentation. [0] b) From a network design perspective, it's a lot easier and more efficient to provide a VLAN that doesn't have Internet egress than to attempt to sort out which of a mess of hosts are permitted to talk to the Internet from which aren't, and ALSO prevent MAC- and/or IP-address spoofing to evade any such filtering. c) I have no idea why you're invoking MQTT (specifically), but any scheme that requires a potentially-untrusted host running potentially-untrusted hardware and software to declare whether or not it's to be trusted is doomed to failure right off the bat. [0] Sure, I'm a power user. But, a "VLAN-isolated network for untrusted machines" feature shouldn't be something that only power users get. This SHOULD be a baseline feature in consumer-grade WiFi APs and switches. (The race-to-the-bottom feature of the "market" for consumer gear is very sad.)
- ndriscoll 2y ago
  Most people have a single combo box for their router/switch/firewall/AP, and maybe modem. For most people, those things are synonymous. The point is isolating devices from each other isn't what people need. They need their devices to accept commands from each other or their computer/phone. What they don't need is their devices to talk to half the Internet. My htpc talks to exactly one machine, for example (my NAS). It's trivial to audit and would work fine if I blocked Internet access or gave it a whitelist. For people that use home assistant, again their devices should need to talk to a broker and that's it. A reasonable device only talks to a handful of locations because you didn't ask it to do anything else. The world where Android and Windows and IoT devices chat all day to thousands of servers is what's the problem. Restricting such devices to only talk to the Internet is exactly the wrong solution. You could lock things down once there's an ecosystem in place for local control, but doing it now just ossifies the existing dumpster fire. If one were to suggest regulation is needed for security (and governments are starting to do so), then what's needed is to ban cloud devices.