Merge pull request #6 from drduh/wip-10mar24

Version 3 beta

.gitignore

@@ -0,0 +1,3 @@
+purse.*.tar
+purse.index
+safe/

LICENSE.md

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2018-2020 drduh
+Copyright (c) 2018 drduh
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -2,65 +2,31 @@
 
 Purse is a fork of [drduh/pwd.sh](https://github.com/drduh/pwd.sh).
 
-Both programs are Bash shell scripts which use [GPG](https://www.gnupg.org/) to manage passwords and other secrets in encrypted text files. Purse uses asymmetric (public-key) authentication, while pwd.sh uses symmetric (password-based) authentication.
+Both programs are Bash shell scripts which use [GnuPG](https://www.gnupg.org/) to manage passwords and other secrets in encrypted text files. Purse is based on asymmetric (public-key) authentication, while pwd.sh is based on symmetric (password-based) authentication.
 
-While both scripts use a trusted crypto implementation (GPG) and safely handle passwords (never saving plaintext to disk), Purse eliminates the need to remember and use a master password - just plug in a YubiKey, enter the PIN, then touch it to decrypt a password to clipboard.
-
-By using Purse with YubiKey, the risk of master password theft or keylogging is eliminated - only physical possession of the Yubikey AND knowledge of the PIN can unlock the encrypted index and password files.
+While both scripts use a trusted crypto implementation (GnuPG) and safely handle passwords (never saving plaintext to disk, only using shell built-ins), Purse eliminates the need to remember a master password - just plug in a YubiKey, enter the PIN, then touch it to decrypt a password to clipboard.
 
 # Release notes
 
-## Version 2b1 (2020)
-
-Minor update to the second release. Currently in beta testing. Compatible on Linux, OpenBSD, macOS.
-
-Known Issues:
-
-* Newer versions of macOS error with `tr: Illegal byte sequence` - see [issue #4](https://github.com/drduh/Purse/issues/4)
-
-
-Changelist:
-
-* Purse now uses a GPG keygroup to encrypt secrets to multiple recipients for improved reliability. The program will prompt for key IDs to define the keygroup; a single key ID can still be used.
-* Encrypted index is now optional and off by default, allowing a single touch to encrypt and decrypt secrets instead of two.
-* GPG configuration file is now included in Purse backup archives.
-
-## Version 2b (2019)
-
-The second release of purse.sh features several security and reliability improvements, and is an optional upgrade. Currently in beta testing. Compatible on Linux, OpenBSD, macOS.
+See [Releases](https://github.com/drduh/Purse/releases)
 
-Known Issues:
-
-* Read actions now require two Yubikey touches, if touch to decrypt is enabled - once for the index and twice for the encrypted password file.
-
-Changelist:
-
-* Passwords are now encrypted as individual files, rather than all encrypted as a single flat file.
-* Individual password filenames are random, mapped to usernames in an encrypted index file.
-* Index and password files are now "immutable" using chmod while purse.sh is not running.
-* Read passwords are now copied to clipboard and cleared after a timeout, instead of printed to stdout.
-* Use printf instead of echo for improved portability.
-* New option: list passwords in the index.
-* New option: create tar archive for backup.
-* Removed option: delete password; the index is now a permanent ledger.
-* Removed option: read all passwords; no use case for having a single command.
-* Removed option: suppress generated password output; should be read from safe to verify save.
+# Use
 
-## Version 1 (2018)
+This script requires a GnuPG identity - see [drduh/YubiKey-Guide](https://github.com/drduh/YubiKey-Guide) to set one up. Multiple identities stored on several YubiKeys are recommended for improved durability and reliability.
 
-The original release which has been available for general use and review since June 2018 (forked from pwd.sh which dates to 2015). There are no known bugs nor security vulnerabilities identified in this stable version of purse.sh.  Compatible on Linux, OpenBSD, macOS.
+Clone the repository:
 
-# Use
+```console
+git clone https://github.com/drduh/Purse
+```
 
-This script requires a GPG identity - see [drduh/YubiKey-Guide](https://github.com/drduh/YubiKey-Guide) to set one up. Multiple identities stored on several YubiKeys are recommended for reliability.
+Or download the script directly:
 
 ```console
-$ git clone https://github.com/drduh/Purse
+wget https://github.com/drduh/Purse/blob/master/purse.sh
 ```
 
-(Version 2b and older) Set your GPG key ID with `export PURSE_KEYID=0xFF3E7D88647EBCDB` or by editing `purse.sh`.
-
-`cd purse.sh` and run the script interactively using `./purse.sh` or symlink to a directory in `PATH`:
+Run the script interactively using `./purse.sh` or symlink to a directory in `PATH`:
 
 * Type `w` to write a password
 * Type `r` to read a password
@@ -72,46 +38,40 @@ Options can also be passed on the command line.
 
 Example usage:
 
-Create a 30-character password for `userName`:
+Create a 20-character password for `userName`:
 
 ```console
-$ ./purse.sh w userName 30
+./purse.sh w userName 20
 ```
 
 Read password for `userName`:
 
 ```console
-$ ./purse.sh r userName
+./purse.sh r userName
 ```
 
-Passwords are stored with a timestamp for revision control. The most recent version is copied to clipboard on read. To list all passwords or read a previous version of a password:
+Passwords are stored with a timestamp for revision control. The most recent version is copied to clipboard on read. To list all passwords or read a specific version of a password:
 
 ```console
-$ ./purse.sh l
+./purse.sh l
 
-$ ./purse.sh r userName@1574723600
+./purse.sh r userName@1574723600
 ```
 
 Create an archive for backup:
 
 ```console
-$ ./purse.sh b
+./purse.sh b
 ```
 
 Restore an archive from backup:
 
 ```console
-$ tar xvf purse*tar
+tar xvf purse*tar
 ```
 
-The backup contains only encrypted passwords and can be publicly shared for use on trusted computers. For additional privacy, the recipient key ID is **not** included in GPG metadata (`throw-keyids` option). The password index file can also be encrypted by changing the `encrypt_index` variable to `true` in the script.
-
-See [drduh/config/gpg.conf](https://github.com/drduh/config/blob/master/gpg.conf) for additional GPG configuration options.
+**Note** For additional privacy, the recipient key ID is **not** included in metadata (`throw-keyids` option).
 
-# Similar software
+The password index file can also be encrypted by changing the `encrypt_index` variable to `true` in the script, although two touches will be required for two separate decryption operations.
 
-* [drduh/pwd.sh](https://github.com/drduh/pwd.sh)
-* [zx2c4/password-store](https://github.com/zx2c4/password-store)
-* [caodonnell/passman.sh: a pwd.sh fork](https://github.com/caodonnell/passman.sh)
-* [bndw/pick: command-line password manager for macOS and Linux](https://github.com/bndw/pick)
-* [anders/pwgen: generate passwords using OS X Security framework](https://github.com/anders/pwgen)
+See [config/gpg.conf](https://github.com/drduh/config/blob/master/gpg.conf) for additional configuration options.

purse.sh

@@ -1,29 +1,33 @@
 #!/usr/bin/env bash
 # https://github.com/drduh/Purse/blob/master/purse.sh
-
 set -o errtrace
 set -o nounset
 set -o pipefail
-
-#set -x # uncomment to debug
+#set -x  # uncomment to debug
 
 umask 077
 
-encrypt_index="false"
-now=$(date +%s)
-copy="$(command -v xclip || command -v pbcopy)"
-gpg="$(command -v gpg || command -v gpg2)"
+cb_timeout=10          # seconds to keep password on clipboard
+daily_backup="false"   # if true, create daily archive on write
+encrypt_index="false"  # if true, requires 2 touches to decrypt
+pass_copy="false"      # if true, keep password on clipboard before write
+pass_len=14            # default password length
+pass_chars="[:alnum:]!@#$%^&*();:+="
+
 gpgconf="${HOME}/.gnupg/gpg.conf"
 backuptar="${PURSE_BACKUP:=purse.$(hostname).$(date +%F).tar}"
 safeix="${PURSE_INDEX:=purse.index}"
 safedir="${PURSE_SAFE:=safe}"
-script="$(basename $BASH_SOURCE)"
-timeout=10
+
+now="$(date +%s)"
+copy="$(command -v xclip || command -v pbcopy)"
+gpg="$(command -v gpg || command -v gpg2)"
+script="$(basename "${BASH_SOURCE}")"
 
 fail () {
   # Print an error message and exit.
 
-  tput setaf 1 1 1 ; printf "\nError: %s\n" "${1}" ; tput sgr0
+  tput setaf 1 ; printf "\nError: %s\n" "${1}" ; tput sgr0
   exit 1
 }
 
@@ -53,7 +57,8 @@ get_pass () {
 decrypt () {
   # Decrypt with GPG.
 
-  cat "${1}" | ${gpg} --armor --batch --decrypt 2>/dev/null
+  cat "${1}" | \
+    ${gpg} --armor --batch --decrypt 2>/dev/null
 }
 
 encrypt () {
@@ -80,17 +85,20 @@ read_pass () {
     prompt_key "index"
 
     spath=$(decrypt "${safeix}" | \
-      grep -F "${username}" | tail -n1 | cut -d ":" -f2) || \
+      grep -F "${username}" | tail -1 | cut -d ":" -f2) || \
         fail "Decryption failed"
   else
     spath=$(grep -F "${username}" "${safeix}" | \
-      tail -n1 | cut -d ":" -f2)
+      tail -1 | cut -d ":" -f2)
   fi
 
   prompt_key "password"
 
-  clip <(decrypt "${spath}" | head -n1) || \
-    fail "Decryption failed"
+  if [[ -s "${spath}" ]] ; then
+    clip <(decrypt "${spath}" | head -1) || \
+      fail "Decryption failed"
+  else fail "Secret not available"
+  fi
 }
 
 prompt_key () {
@@ -104,28 +112,30 @@ prompt_key () {
 gen_pass () {
   # Generate a password using GPG.
 
-  len=20
-  max=80
-
   if [[ -z "${3+x}" ]] ; then read -r -p "
 
-  Password length (default: ${len}, max: ${max}): " length
+  Password length (default: ${pass_len}): " length
   else length="${3}" ; fi
 
-  if [[ ${length} =~ ^[0-9]+$ ]] ; then len=${length} ; fi
+  if [[ ${length} =~ ^[0-9]+$ ]] ; then pass_len=${length} ; fi
 
-  # base64: 4 characters for every 3 bytes
-  ${gpg} --armor --gen-random 0 "$((max * 3 / 4))" | cut -c -"${len}"
+  LC_LANG=C tr -dc "${pass_chars}" < /dev/urandom | \
+    fold -w "${pass_len}" | head -1
 }
 
 write_pass () {
-  # Write a password and update index file.
+  # Write a password and update the index.
+
+  if [[ "${pass_copy}" = "true" ]] ; then
+    clip <(printf '%s' "${userpass}")
+  fi
 
-  fpath=$(LC_LANG=C tr -dc "[:lower:]" < /dev/urandom | fold -w8 | head -n1)
-  spath=${safedir}/${fpath}
+  fpath="$(LC_LANG=C tr -dc '[:lower:]' < /dev/urandom | fold -w10 | head -1)"
+  spath="${safedir}/${fpath}"
   printf '%s\n' "${userpass}" | \
     encrypt "${spath}" - || \
       fail "Failed to put ${spath}"
+  userpass=""
 
   if [[ "${encrypt_index}" = "true" ]] ; then
     prompt_key "index"
@@ -139,7 +149,6 @@ write_pass () {
   else
     printf "%s@%s:%s\n" "${username}" "${now}" "${spath}" >> "${safeix}"
   fi
-
 }
 
 list_entry () {
@@ -151,21 +160,22 @@ list_entry () {
     prompt_key "index"
     decrypt "${safeix}" || fail "Decryption failed"
   else
+    printf "\n"
     cat "${safeix}"
   fi
 }
 
 backup () {
-  # Create an archive for backup.
+  # Archive index, safe and configuration.
 
-  if [[ -f "${safeix}" ]] ; then
+  if [[ -f "${safeix}" && -d "${safedir}" ]] ; then
     cp "${gpgconf}" "gpg.conf.${now}"
-    tar cfv "${backuptar}" \
+    tar --create --file "${backuptar}" \
       "${safeix}" "${safedir}" "gpg.conf.${now}" "${script}"
     rm "gpg.conf.${now}"
   else fail "Nothing to archive" ; fi
 
-  printf "\nArchived %s \n" "${backuptar}"
+  printf "\nArchived %s\n" "${backuptar}"
 }
 
 clip () {
@@ -175,17 +185,17 @@ clip () {
 
   printf "\n"
   shift
-  while [ $timeout -gt 0 ] ; do
-    printf "\r\033[KPassword on clipboard! Clearing in %.d" $((timeout--))
+  while [ $cb_timeout -gt 0 ] ; do
+    printf "\r\033[KPassword on clipboard! Clearing in %.d" $((cb_timeout--))
     sleep 1
   done
 
+  printf "\n"
   printf "" | ${copy}
 }
 
-
 setup_keygroup() {
-  # Configure GPG keygroup setting.
+  # Configure GPG keygroup.
 
   purse_keygroup="group purse_keygroup ="
   keyid=""
@@ -212,7 +222,7 @@ setup_keygroup() {
 }
 
 new_entry () {
-  # Prompt for new username and/or password.
+  # Prompt for username and password.
 
   username=""
   while [[ -z "${username}" ]] ; do
@@ -226,7 +236,9 @@ new_entry () {
     userpass="${password}"
   fi
 
-  if [[ -z "${password}" ]] ; then userpass=$(gen_pass "$@") ; fi
+  if [[ -z "${password}" ]] ; then
+    userpass=$(gen_pass "$@")
+  fi
 }
 
 print_help () {
@@ -250,7 +262,7 @@ print_help () {
     * Copy the password for 'userName' to clipboard:
         ./purse.sh r userName
 
-    * List stored passwords and copy a previous version:
+    * List stored passwords and copy a specific version:
         ./purse.sh l
         ./purse.sh r userName@1574723625
 
@@ -263,21 +275,21 @@ print_help () {
 
 if [[ -z ${gpg} && ! -x ${gpg} ]] ; then fail "GnuPG is not available" ; fi
 
-if [[ ! -f ${gpgconf} ]] ; then fail "GnuPG config is not available" ; fi
-
 if [[ -z ${copy} && ! -x ${copy} ]] ; then fail "Clipboard is not available" ; fi
 
-if [[ ! -d ${safedir} ]] ; then mkdir -p ${safedir} ; fi
+if [[ ! -f ${gpgconf} ]] ; then fail "GnuPG config is not available" ; fi
+
+if [[ ! -d "${safedir}" ]] ; then mkdir -p "${safedir}" ; fi
 
-chmod -R 0600 ${safeix}  2>/dev/null
-chmod -R 0700 ${safedir} 2>/dev/null
+chmod -R 0600 "${safeix}"  2>/dev/null
+chmod -R 0700 "${safedir}" 2>/dev/null
 
 password=""
 action=""
 if [[ -n "${1+x}" ]] ; then action="${1}" ; fi
 
 while [[ -z "${action}" ]] ; do
-  read -n 1 -p "
+  read -r -n 1 -p "
   Read or Write (or Help for more options): " action
   printf "\n"
 done
@@ -301,8 +313,14 @@ elif [[ "${action}" =~ ^([wW])$ ]] ; then
   new_entry "$@"
   write_pass
 
+  if [[ "${daily_backup}" = "true" ]] ; then
+    if [[ ! -f ${backuptar} ]] ; then
+      backup
+    fi
+  fi
+
 else read_pass "$@" ; fi
 
-chmod -R 0400 ${safeix} ${safedir} 2>/dev/null
+chmod -R 0400 "${safeix}" "${safedir}" 2>/dev/null
 
-tput setaf 2 2 2 ; printf "\nDone\n" ; tput sgr0
+tput setaf 2 ; printf "\nDone\n" ; tput sgr0