Build Your Own Password Manager

This is a (work-in-progress) tutorial that will teach you shell scripting by showing you how to build the pass password manager in small steps.

Assumptions

• Basic shell knowledge (cd, ls)
• Basic programming experience (variables, functions, conditionals, loops)
• Basic understanding of git will help in the section where we add git support (not too important)

The Plan

1. A password generator

• Step 1: echo "correcthorsebatterystaple"
• Generate a random string
• The generate command
• The version command
• The help command

2. Storing plaintext passwords

• Save generated password to $PREFIX
• The show command
• Make show the default command
• The insert command
• The rm command
• The mv command
• The cp command

3. Encryption

• The init command
• GPG options and whether to use gpg2
• gpg_winpath() for Cygwin
• set_gpg_recipients()
• Encrypt with generate and insert commands
• Decrypt with show command
• Reencrypt using init command

4. Copy to clipboard

• Generic clip()
• Cygwin clip()
• macOS clip()
• -c option for generate and show commands
• Clear clipboard after 45 seconds
• Reset 45-second timer before starting a new one
• Restore previous clipboard contents

5. Getopt

• Find GNU getopt for the platform
• Use it for -c/--clip switch
• More switches

5. QR codes

• Generic qrcode()
• macOS qrcode()
• -q option for generate and show commands

6. Secure text editing

• The edit command
• Generic tmpdir()
• macOS tmpdir()
• FreeBSD $SHRED
• OpenBSD tmpdir()

7. Listing and searching

• The ls command
• The find command
• The grep command

8. Git

• The git command
• set_git()
• git_add_file()
• git_commit()
• Add git support to generate and insert commands
• Add git support to edit, rm, mv, cp commands

9. Completion

• bash completion
• zsh completion
• fish completion

10. Signing and verification

• Sign .gpg_id in init command
• verify_file()
• Sign git commits

11. Multiple users

• --path option for init command

12. User extensions

• cmd_extension()
• An example: pass-update