askpass

Password Entry Utilities for R, Git, and SSH

Cross-platform utilities for prompting the user for credentials or a passphrase, for example to authenticate with a server or read a protected key. Includes native programs for MacOS and Windows, hence no ‘tcltk’ is required. Password entry can be invoked in two different ways: directly from R via the askpass() function, or indirectly as password-entry back-end for ‘ssh-agent’ or ‘git-credential’ via the SSH_ASKPASS and GIT_ASKPASS environment variables. Thereby the user can be prompted for credentials or a passphrase if needed when R calls out to git or ssh.

Called from R

To invoke the password prompt manually use:

askpass::askpass()

This is used for example to read protected key files:

library(openssl)
key <- rsa_keygen()
write_pem(key, 'testkey.pem', password = 'supersecret')
read_key('testkey.pem')

Called from SSH / Git

The package also configures itself as the password entry back-end for ssh-agent and git-credential. The easiest way to test this is using the credentials package:

remotes::install_github("r-lib/credentials")
git_credential_ask('https://example.com')

R for MacOS

RStudio (server, desktop)

RGUI / Windows

Terminal