From f3eeab9d9c5bce15bf4c797763f78c455da3550c Mon Sep 17 00:00:00 2001
From: earnest ma <me@earne.link>
Date: Mon, 27 Dec 2021 20:45:00 -0500
Subject: [PATCH] bin: Add pash script

---
 bin/.local/bin/pash | 242 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 242 insertions(+)
 create mode 100755 bin/.local/bin/pash

diff --git a/bin/.local/bin/pash b/bin/.local/bin/pash
new file mode 100755
index 0000000..bb0d3f9
--- /dev/null
+++ b/bin/.local/bin/pash
@@ -0,0 +1,242 @@
+#!/bin/sh
+#
+# pash - simple password manager.
+# Licensed under the MIT License
+
+pw_add() {
+    name=$1
+
+    if yn "Generate a password?"; then
+        # Generate a password by reading '/dev/urandom' with the
+        # 'tr' command to translate the random bytes into a
+        # configurable character set.
+        #
+        # The 'dd' command is then used to read only the desired
+        # password length.
+        #
+        # Regarding usage of '/dev/urandom' instead of '/dev/random'.
+        # See: https://www.2uo.de/myths-about-urandom
+        pass=$(LC_ALL=C tr -dc "${PASH_PATTERN:-_A-Z-a-z-0-9}" < /dev/urandom |
+            dd ibs=1 obs=1 count="${PASH_LENGTH:-50}" 2>/dev/null)
+
+    else
+        # 'sread()' is a simple wrapper function around 'read'
+        # to prevent user input from being printed to the terminal.
+        sread pass  "Enter password"
+        sread pass2 "Enter password (again)"
+
+        # Disable this check as we dynamically populate the two
+        # passwords using the 'sread()' function.
+        # shellcheck disable=2154
+        [ "$pass" = "$pass2" ] || die "Passwords do not match"
+    fi
+
+    [ "$pass" ] || die "Failed to generate a password"
+
+    # Mimic the use of an array for storing arguments by... using
+    # the function's argument list. This is very apt isn't it?
+    if [ "$PASH_KEYID" ]; then
+        set -- --trust-model always -aer "$PASH_KEYID"
+    else
+        set -- -c
+    fi
+
+    # Use 'gpg' to store the password in an encrypted file.
+    # A heredoc is used here instead of a 'printf' to avoid
+    # leaking the password through the '/proc' filesystem.
+    #
+    # Heredocs are sometimes implemented via temporary files,
+    # however this is typically done using 'mkstemp()' which
+    # is more secure than a leak in '/proc'.
+    "$gpg" "$@" -o "$name.gpg" <<-EOF &&
+		$pass
+	EOF
+    printf '%s\n' "Saved '$name' to the store."
+}
+
+pw_del() {
+    yn "Delete pass file '$1'?" && {
+        rm -f "$1.gpg"
+
+        # Remove empty parent directories of a password
+        # entry. It's fine if this fails as it means that
+        # another entry also lives in the same directory.
+        rmdir -p "${1%/*}" 2>/dev/null || :
+    }
+}
+
+pw_show() {
+    "$gpg" -dq "$1.gpg"
+}
+
+pw_copy() {
+    # Disable warning against word-splitting as it is safe
+    # and intentional (globbing is disabled).
+    # shellcheck disable=2086
+    : "${PASH_CLIP:=xclip -sel c}"
+
+    # Wait in the background for the password timeout and
+    # clear the clipboard when the timer runs out.
+    #
+    # If the 'sleep' fails, kill the script. This is the
+    # simplest method of aborting from a subshell.
+    [ "$PASH_TIMEOUT" != off ] && {
+        printf 'Clearing clipboard in "%s" seconds.\n' "${PASH_TIMEOUT:=15}"
+
+        sleep "$PASH_TIMEOUT" || kill 0
+        $PASH_CLIP </dev/null
+    } &
+
+    pw_show "$1" | $PASH_CLIP
+}
+
+pw_list() {
+    find . -type f -name \*.gpg | sed 's/..//;s/\.gpg$//'
+}
+
+pw_tree() {
+    command -v tree >/dev/null 2>&1 ||
+        die "'tree' command not found"
+
+    tree --noreport | sed 's/\.gpg$//'
+}
+
+yn() {
+    printf '%s [y/n]: ' "$1"
+
+    # Enable raw input to allow for a single byte to be read from
+    # stdin without needing to wait for the user to press Return.
+    stty -icanon
+
+    # Read a single byte from stdin using 'dd'. POSIX 'read' has
+    # no support for single/'N' byte based input from the user.
+    answer=$(dd ibs=1 count=1 2>/dev/null)
+
+    # Disable raw input, leaving the terminal how we *should*
+    # have found it.
+    stty icanon
+
+    printf '\n'
+
+    # Handle the answer here directly, enabling this function's
+    # return status to be used in place of checking for '[yY]'
+    # throughout this program.
+    glob "$answer" '[yY]'
+}
+
+sread() {
+    printf '%s: ' "$2"
+
+    # Disable terminal printing while the user inputs their
+    # password. POSIX 'read' has no '-s' flag which would
+    # effectively do the same thing.
+    stty -echo
+    read -r "$1"
+    stty echo
+
+    printf '\n'
+}
+
+glob() {
+    # This is a simple wrapper around a case statement to allow
+    # for simple string comparisons against globs.
+    #
+    # Example: if glob "Hello World" '* World'; then
+    #
+    # Disable this warning as it is the intended behavior.
+    # shellcheck disable=2254
+    case $1 in $2) return 0; esac; return 1
+}
+
+die() {
+    printf 'error: %s.\n' "$1" >&2
+    exit 1
+}
+
+usage() { printf %s "\
+pash 2.3.0 - simple password manager.
+
+=> [a]dd  [name] - Create a new password entry.
+=> [c]opy [name] - Copy entry to the clipboard.
+=> [d]el  [name] - Delete a password entry.
+=> [l]ist        - List all entries.
+=> [s]how [name] - Show password for an entry.
+=> [t]ree        - List all entries in a tree.
+
+Using a key pair:  export PASH_KEYID=XXXXXXXX
+Password length:   export PASH_LENGTH=50
+Password pattern:  export PASH_PATTERN=_A-Z-a-z-0-9
+Store location:    export PASH_DIR=~/.local/share/pash
+Clipboard tool:    export PASH_CLIP='xclip -sel c'
+Clipboard timeout: export PASH_TIMEOUT=15 ('off' to disable)
+"
+exit 0
+}
+
+main() {
+    : "${PASH_DIR:=${XDG_DATA_HOME:=$HOME/.local/share}/pash}"
+
+    # Look for both 'gpg' and 'gpg2',
+    # preferring 'gpg2' if it is available.
+    command -v gpg  >/dev/null 2>&1 && gpg=gpg
+    command -v gpg2 >/dev/null 2>&1 && gpg=gpg2
+
+    [ "$gpg" ] ||
+        die "GPG not found"
+
+    mkdir -p "$PASH_DIR" ||
+        die "Couldn't create password directory"
+
+    cd "$PASH_DIR" ||
+        die "Can't access password directory"
+
+    glob "$1" '[acds]*' && [ -z "$2" ] &&
+        die "Missing [name] argument"
+
+    glob "$1" '[cds]*' && [ ! -f "$2.gpg" ] &&
+        die "Pass file '$2' doesn't exist"
+
+    glob "$1" 'a*' && [ -f "$2.gpg" ] &&
+        die "Pass file '$2' already exists"
+
+    glob "$2" '*/*' && glob "$2" '*../*' &&
+        die "Category went out of bounds"
+
+    glob "$2" '/*' &&
+        die "Category can't start with '/'"
+
+    glob "$2" '*/*' && { mkdir -p "${2%/*}" ||
+        die "Couldn't create category '${2%/*}'"; }
+
+    # Set 'GPG_TTY' to the current 'TTY' if it
+    # is unset. Fixes a somewhat rare `gpg` issue.
+    export GPG_TTY=${GPG_TTY:-$(tty)}
+
+    # Restrict permissions of any new files to
+    # only the current user.
+    umask 077
+
+    # Ensure that we leave the terminal in a usable
+    # state on exit or Ctrl+C.
+    [ -t 1 ] && trap 'stty echo icanon' INT EXIT
+
+    case $1 in
+        a*) pw_add  "$2" ;;
+        c*) pw_copy "$2" ;;
+        d*) pw_del  "$2" ;;
+        s*) pw_show "$2" ;;
+        l*) pw_list ;;
+        t*) pw_tree ;;
+        *)  usage
+    esac
+}
+
+# Ensure that debug mode is never enabled to
+# prevent the password from leaking.
+set +x
+
+# Ensure that globbing is globally disabled
+# to avoid insecurities with word-splitting.
+set -f
+
+[ "$1" ] || usage && main "$@"