Kryptonite
Security and privacy
ssh key management
SHOW HN2017
338points
219comments
#58of 2,242 in 2017
Top 3%of 2017 by points
How HN took it
MixedNo clear lean
23 positive, 35 neutral or asking, 5 mixed, 30 critical, out of 93 comments about the project. Thread score -0.08.
Privacy: 5 for, 15 againstExecution: 4 for, 7 againstIdea: 2 for, 4 againstDesign: 4 for, 1 againstDocs: 1 for, 1 against
The thread, comment by comment
Each row is a top-level comment and its replies, in HN's order. Select a cell to open that comment on HN.
positive neutral or mixed critical about another commenter or something else the maker
What HN said
What people liked
Good idea that uses the client instead of the server
From 2 comments
Clever that it uses the client instead of the server! I've dabbled with phone-based authentication via a server-side PAM module before, but you generally don't have full control…
y7 on HNI haven't reviewed the implementation, but this is a really good idea. I want one.
tptacek on HN
Phones are more secure than laptops for keys
From 2 comments
* Every application on the phone is sandboxed. * The disk is encrypted by default, and the OS is aggressive about keeping it encrypted; a booted-up computer is almost always…
tptacek on HNHSIC is USB. It's an industry standard. In modern flagship phone designs, the baseband is an adversarial component. It isn't trusted with access to AP memory. It's accessed like…
tptacek on HN
Objections
Cannot back up the private key; losing the phone is a risk
From 3 comments
Obvious question - What happens when the phone containing the private key is lost?
bizzleDawg on HNThe faq says there is intentionally no way to extract the private key due to security. But this means I need a second account in case my phone gets lost - the key of which I once…
xg15 on HNYour FAQ says you cannot backup your private key. So does that mean if your service gets attacked by DDoS or has unexpected downtime, you will not be able to SSH into your server?
trizic on HN
Android lacks ed25519 and key import/paper backup at launch
From 2 comments
This looks interesting but until Ed25519 on Android, importing existing keys and Paper Backups are supported it's a no-go for me. For some things I trust a paper backup in a…
tscs37 on HN1) We are planning to support multiple private keys, but currently only support a single key pair. 2) Android doesn't yet support ed25519 but it is coming. 3) We would consider…
4kevinking on HN
Phone trust and malware concerns versus hardware tokens
From 2 comments
It sounds very hipster and all, but how is a phone more trustworthy than a Linux PC? Cool, we don't need to trust a PC, now we have to trust a phone and pretend that malware for…
shmel on HNThe attack surface may seem smaller for USB tokens, but storing the pin for say a Yubikey allows malware to use the key without restriction. Also, these USB devices don't have a…
4kevinking on HN
Requests
Support multiple keys
From 2 comments
1) We are planning to support multiple private keys, but currently only support a single key pair. 2) Android doesn't yet support ed25519 but it is coming. 3) We would consider…
4kevinking on HNCorrect, we currently only support one key, but multiple key support is in the works!
4kevinking on HN
Key backup or transfer to other devices
From 2 comments
The current version is designed for hosted services like GitHub, redeployable infrastructure, and servers to which multiple people have access. We totally understand your use…
4kevinking on HNThat is correct. We will also soon release a way to copy a key from one device to another by scanning a QR code.
4kevinking on HN
Fish shell support
From 1 comment
Looks interesting. However, it seems to maybe assume you're using bash? Using the fish-shell it seems to have simply broken ssh and git operations with incorrect syntax. I had to…
snowpalmer on HN
Questions
What happens if the phone is lost?
From 1 comment
Obvious question - What happens when the phone containing the private key is lost?
bizzleDawg on HN
Are communications routed through Kryptonite servers?
From 2 comments
Are the communications between the phone and the computer going via the kryptonite servers?
akerl_ on HNNo -- we treat every communication channel as untrusted. All communication between the phone and computer is encrypted with session keys established when you pair by scanning the…
4kevinking on HN
Alternatives named
Yubikey and other USB hardware tokens
From 2 comments
Seems quite similar to using a Yubikey to house your SSH key, just with bluetooth and your phone. A bit less secure, but still quite the interesting tool.
falcolas on HNIt sounds very hipster and all, but how is a phone more trustworthy than a Linux PC? Cool, we don't need to trust a PC, now we have to trust a phone and pretend that malware for…
shmel on HN
Ledger Nano S SSH applet
From 1 comment
There's a GPG/SSH applet for the ledger Nano S now that has a tiny screen and buttons...
simonvc on HN