checkkey.sh - Check key about GNUPG.

checkkey.sh

#!/usr/bin/env bash
# 
# checkkey.sh - Check key about GNUPG.
# Copyright (c) 2022 Koichi OKADA. All rights reserved.
# This script is distributed under the MIT license.
#

SGR0="\e[0m"
SGR1="\e[1m"
SGR31="\e[31m"
SGR32="\e[32m"

function checkkey () # <keyfile>
#   Check key about GNUPG.
# Arguments:
#   <keyfile>    Key file for the GNU PG.
# Environment variables:
#   $OPT_UTC     If set, use UTC timestamp.
{
  local pubring stamp GNUPGHOME trash
  pubring="$1"
  
  if ! [[ -f "$pubring" && -r "$pubring" ]]; then
    echo -e "$SGR31${SGR1}Error:$SGR0 Can not access pubring. : $pubring"
    return 1
  fi >&2
  
  [ -z "$stamp" ] && read stamp < <(date ${OPT_UTC:+-u }-r "$pubring" "+%Y%m%dT%H%M%S%z")
  if [ -z "$stamp" ]; then
    echo -e "$SGR31${SGR1}Error:$SGR0 filename does not have time stamp."
    return 1
  fi >&2

  printf -v trash "/tmp/trash/%(%Y%m%d_%H%M%S)T"
  if ! mkdir -p "$trash"; then
    echo -e "$SGR31${SGR1}Error:$SGR0 Can not prepare trash directory. : $trash"
    return 1
  fi >&2

  GNUPGHOME="/tmp/.checkkey/$stamp"

  if [ -d "$GNUPGHOME" ]; then
    echo -e "$SGR31${SGR1}Error:$SGR0 Tempolary GNUPGHOME is already exist. : $GNUPGHOME"
    echo "Suggestion:"
    echo "  rm -rv \"$GNUPGHOME\""
    return 1
  fi >&2

  if ! { mkdir -p "$GNUPGHOME" && chmod 700 "$GNUPGHOME"; }; then
    echo -e "$SGR31${SGR1}Error:$SGR0 Can not prepare GNUPGHOME. : $GNUPGHOME"
    return 1
  fi

  gpg --import "$pubring" >&/dev/null
  echo -e "$SGR32$SGR1[Public keys]$SGR0"
  gpg -k
  echo -e "$SGR32$SGR1[Secret keys]$SGR0"
  gpg -K
  echo -e "$SGR32$SGR1[Signatures]$SGR0"
  gpg --check-sigs

  mv "$GNUPGHOME" "$trash/"
}

function gpg ()
#   GNUPG wrapper
{
  LANG=C GNUPGHOME="$GNUPGHOME" gpg2 "$@"
}

function function_usage () # <file> <regex>
#   Show usage of function.
# Arguments:
#   <file>  File of source code.
#   <regex> Pattern for matching function name.
{
  awk -vpat="${2:-.}" '
    match($0, /^(function\s+)?(\S+)\s*\(\)\s*(\x23.*)$/, m) {name=m[2];n=-1;}
    name!="" {if (match($0, /^{/)) {name=null;} else {n++;}}
    match(name, pat) {
      if (n == 0) {
        gsub(/^function\s*/,"");
        sub(/\s*\(\)\s*\x23?/,"");
        printf("Usage: ");
      }
      sub(/^\x23 ?/,"");
      if (!match($0,/^{/)) print $0;
    }
  ' "$1"
}

if (( $# <= 0 )); then
  function_usage "$BASH_SOURCE" checkkey
  exit
fi

for i; do
  checkkey "$i"
done