README
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a2fa
a2fa ("annoying two-factor authentication") is a command line tool for generating and validating one-time password.
Introduction
a2fa means annoying two-factor authentication. Its purpose is to get rid of phones and be able to authenticate easily. It keeps synced with Google Authenticator, Microsoft Authenticator.
Description:
- An easy-to-use substitute for 2FA apps like TOTP Google authenticator.
- Supports the OATH algorithms, such as TOTP and HOTP.
- No need for network connection.
- No need for phone.
Installation instructions
Linux
One-liner bash script to install a2fa
sudo -v ; curl https://raw.githubusercontent.com/csyezheng/a2fa/main/scripts/install.sh | sudo bash
macOS
One-liner bash script to install a2fa
sudo -v ; curl https://raw.githubusercontent.com/csyezheng/a2fa/main/scripts/install.sh | sudo bash
Windows
One-liner PowerShell script to install a2fa
Invoke-Expression "& { $(Invoke-RestMethod 'https://raw.githubusercontent.com/csyezheng/a2fa/main/scripts/install.ps1') }"
Manual installation and more
Please see the installation
Usage
a2fa [command] [flags] [args]
Available Commands:
add Add account and its secret key
completion Generate the autocompletion script for the specified shell
generate Generate one-time password from secret key
help Help about any command
list List all added accounts and password code
remove Remove account and its secret key
update Add account and its secret key
version show version
a2fa generate [flags] <secret key>
a2fa add [flags] <account name> <secret key>
a2fa remove <account name> [user name]
a2fa update [flags] <account name> <secret key>
a2fa list [account name]
Commonly used flags
Flags:
-b, --base32 use base32 encoding of KEY instead of hex (default true)
-c, --counter int used for HOTP, A counter C, which counts the number of iterations
-e, --epoch int used for TOTP, epoch (T0) which is the Unix time from which to start counting time steps
-H, --hash string A cryptographic hash method H (SHA1, SHA256, SHA512) (default "SHA1")
-h, --help help for generate
-i, --interval int used for TOTP, an interval (Tx) which will be used to calculate the value of the counter CT (default 30)
-l, --length int A HOTP value length d (default 6)
-m, --mode string use use time-variant TOTP mode or use event-based HOTP mode (default "totp")
Examples
Generate code
Generate a time-based one-time password but do not save the secret key
a2fa generate ADOO3MCCCVO5AVD6
Generate a counter-based one-time password with counter 1
a2fa generate -m hotp -c 1 ADOO3MCCCVO5AVD6
Add account
Add an account named GitHub
a2fa add GitHub ADOO3MCCCVO5AVD6
Add an account, the account name is GitHub, the user name is csyezheng
a2fa add GitHub:csyezheng ADOO3MCCCVO5AVD6
List acccount
List all accounts
a2fa list
List all accounts named GitHub
a2fa list GitHub
List accounts whose account name is GitHub and whose username is csyezheng
a2fa list GitHub:csyezheng
List accounts whose account name is GitHub and whose username is csyezheng
a2fa list GitHub csyezheng
Remove accounts
Remove all accounts named GitHub
a2fa remove GitHub
Delete accounts whose account name is GitHub and whose username is csyezheng
a2fa remove GitHub csyezheng
Update acccount
Update the secret key of accounts which account name is GitHub
a2fa update GitHub 5BRSSSBJUWBQBOXE
Update the secret key of accounts which account name is GitHub and the username is csyezheng
a2fa update GitHub:csyezheng 5BRSSSBJUWBQBOXE
Reporting issues
If you encounter any problems, you can open an issue in our bug tracker, please fill the issue template with as much information as possible.
Contributing
Refer to CONTRIBUTING.md
License
Apache License 2.0, see LICENSE.
Directories