
OpenSSL uses PKCS#5 padding, and the decryption code was not removing it correctly. In some cases, this causes the last line of the decrypted config to be mangled and produces invalid results. To support this: - Move config loading to gauth.LoadConfigFile. - Inject a hook to read the user's password. - Add unit tests that decryption doesn't corrupt the result. - Update module dependencies. - Update Go versions in CI, and fix some config-check warnings.
gauth: replace Google Authenticator
Installation
With a Go environment already set up, it should be as easy as go get github.com/pcarrier/gauth
.
Eg, with GOPATH=$HOME/go
, it will create a binary $HOME/go/bin/gauth
.
Usage
-
In web interfaces, pretend you can't read QR codes, get a secret like
hret 3ij7 kaj4 2jzg
instead. -
Store one secret per line in
~/.config/gauth.csv
, in the formatname:secret
. For example:AWS: ABCDEFGHIJKLMNOPQRSTUVWXYZ234567ABCDEFGHIJKLMNOPQRSTUVWXYZ234567 Airbnb:abcd efgh ijkl mnop Google:a2b3c4d5e6f7g8h9 Github:234567qrstuvwxyz
-
Restrict access to your user:
$ chmod 600 ~/.config/gauth.csv
-
Run
gauth
. The progress bar indicates how far the next change is.$ gauth prev curr next AWS 315306 135387 483601 Airbnb 563728 339206 904549 Google 453564 477615 356846 Github 911264 548790 784099 [======= ]
-
gauth
is convenient to use inwatch
.$ watch -n1 gauth
-
Remember to keep your system clock synchronized and to lock your computer when brewing your tea!
Encryption
gauth
supports password-based encryption of gauth.csv
. To encrypt, use:
$ openssl enc -aes-128-cbc -md sha256 -in gauth.csv -out ~/.config/gauth.csv
enter aes-128-cbc encryption password:
Verifying - enter aes-128-cbc encryption password:
gauth
will then prompt you for that password on every run:
$ gauth
Encryption password:
prev curr next
LastPass 915200 479333 408710
Note that this encryption mechanism is far from ideal from a pure security standpoint. Please read OpenSSL's notes on the subject.
Compatibility
Tested with:
- Airbnb
- Apple
- AWS
- DreamHost
- Dropbox
- Evernote
- Gandi
- Github
- LastPass
- Linode
- Microsoft
- Okta (reported by Bryan Baldwin)
- WP.com
- bittrex.com
- poloniex.com
Please report further results to pierre@gcarrier.fr.
Rooted Android?
If your Android phone is rooted, it's easy to "back up" your secrets from an adb shell
into gauth
.
# sqlite3 /data/data/com.google.android.apps.authenticator2/databases/database \
'select email,secret from accounts'
Really, does this make sense?
At least to me, it does. My laptop features encrypted storage, a stronger authentication mechanism, and I take good care of its physical integrity.
My phone also runs arbitrary apps, is constantly connected to the Internet, gets forgotten on tables.
Thanks to the convenience of a command line utility, my usage of 2-factor authentication went from 3 to 10 services over a few days.
Clearly a win for security.