#!/bin/bash
set -euo pipefail

check_cert_validity() {
  local cert=("${@}")

  # Get validity dates of certificate
  local expire=$(printf "%s\\n" "${cert[@]:1}" \
    | openssl x509 \
      -noout \
      -dates \
    | sed '/notAfter/!d;s/notAfter=//g;s/ /\\ /g' \
    | xargs date +%s -d
  )

  # Checks if certificate is valid at this date
  if [[ ${expire} -gt $(date +%s -d now) ]]; then
    return 0
  else
    printf "%s: %s [%s %s]\\n" \
      $"-- WARNING" \
      $"Certificate was expired" \
      $"Fingerprint=(SHA256)" \
      ${cert[0]}
    return 1
  fi
}

unzip_fingerprint() {
  local zip_source=${1:-}
  local fp_algo=sha256

  local files=$(
      [[ -f "${zip_source}" ]] && \
        (unzip -qql ${zip_source} | awk '{print $4}')
    )

  # Unzip cert into array and compute their fingerprint
  printf "%s: %s\\n" $"Archive" "${zip_source}"
  local file; for file in ${files}; do
    readarray -t cert < <(
      unzip -p ${zip_source} ${file} \
      | openssl x509 \
        -fingerprint \
	      -${fp_algo} \
      | sed 's/.*Fingerprint=//g;s/://g'
    )

    # Check validity dates of certificate then writes it to disk
    if check_cert_validity "${cert[@]}"; then
      local cert_file="certs/${cert[0]}.crt"
      printf "  %s %s\\n" $"Inflating" "certs/${file}"
      #printf "  %s %s\\n" $"Inflating" "certs/${cert[0]}.crt"
      #printf "  - %s=(%s) %s\\n" "Fingerprint" "${fp_algo^^}" "${cert[0]}"
      printf "%s\\n" "${cert[@]:1}" > "${cert_file}"
    fi
  done
}

copy_fingerprint() {
  local cert_source=${1:-}
  local fp_algo=sha256

  readarray -t cert < <(
    cat ${cert_source} \
      | openssl x509 \
        -fingerprint \
        -${fp_algo} \
      | sed 's/.*Fingerprint=//g;s/://g'
  )

  # Check validity dates of certificate then writes it to disk
  if check_cert_validity "${cert[@]}"; then
    local cert_file="certs/${cert[0]}.crt"
    printf "%s %s\\n" $"Copying" "certs/${cert_source}"
    printf "%s\\n" "${cert[@]:1}" > "${cert_file}"
  fi
}

#split() {
#  local certs=("${@}")
#
#  printf "%s\\n" "${certs[@]}" \
#  | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' \
#  | csplit \
#    --quiet \
#    --elide-empty-files \
#    --prefix ${random_prefix:-}-cert \
#    --suffix-format=-%02d.crt \
#    - '/-END CERTIFICATE-/1' \
#   '{*}'
#}

function extract() {
  local file
  mkdir -p certs
  find cache -type f | while read file; do
    case "$(file -b --mime-type ${file})" in
      application/zip) unzip_fingerprint "${file}" ;;
      application/x-pem-file) copy_fingerprint ${file} ;;
    esac
  done
}


function classify() {
  # Create classified output directories
  mkdir -p certs/{ca-root,ca-trust,servers}

  # Process and classify generated files
  echo -e "\n-- CLASSIFYING CACHED CERTIFICATES\n"
  count=0
  cert_files=$(find certs/ -maxdepth 1 -type f)
  for cert_file in ${cert_files}; do
    fingerprint="(SHA256) ${cert_file}"
    echo "+ Processing certificate [Fingerprint: ${fingerprint}]"
    issuer=$(openssl x509 -in "${cert_file}" -noout -issuer | sed 's/^issuer=//g')
    issuer_o=$(echo "${issuer}" | grep -iPo 'O\s*=\s*\K[^,]+' || :)
    subject=$(openssl x509 -in "${cert_file}" -noout -subject | sed 's/^subject=//g')
    subject_o=$(echo "${subject}" | grep -iPo 'O\s*=\s*\K[^,]+' || :)
    subject_cn=$(echo "${subject}" | grep -iPo 'CN\s*=\s*\K[^,]+' || :)
    cert_o=$(echo "${subject_o^^}" | sed -E "s/\s/_/g;s/'//g;s/\/.*//g;s/\*\.//g")
    cert_cn=$(echo "${subject_cn}" | sed -E "s/\s/_/g;s/\/.*//g;s/^\*\./wildcard-/g")

    # save temporary pem file to .CRT file
    if [[  "${subject_cn}" =~ "gov.br" ]]; then # it's a server certificate
      cert_crt_file="${issuer_o^^}-${cert_cn}.crt"
      openssl x509 -in "${cert_file}" -out "certs/servers/${cert_crt_file}"
      let count=count+1
    elif [[ "${subject}" == "${issuer}" ]]; then # it's a root certificate (self-signed)
      cert_crt_file="${cert_o}-${cert_cn}.crt"
      openssl x509 -in "${cert_file}" -out "certs/ca-root/${cert_crt_file}"
      let count=count+1
    else # it's an intermediate certificate
      cert_crt_file="${cert_o}-${cert_cn}.crt"
      openssl x509 -in "${cert_file}" -out "certs/ca-trust/${cert_crt_file}"
      let count=count+1
    fi
  done
  echo "-- Processed certificates: ${count}"
}

function anchors() {
  echo -e "\n-- GENERATING P11-KIT SOURCE ANCHORS"
  
  local ca_list=$(
    (for cert in certs/{ca-root,ca-trust}/*.crt; do
      openssl x509 -in ${cert} -noout -subject \
        | grep -iPo 'O\s*=\s*\K[^,]+' \
        | sed -E "s/\s/_/g;s/'//g;s/\/.*//g;s/\*\.//g;s/.*/\U&/";
     done;
    for cert in certs/servers/*.crt; do
      openssl x509 -in ${cert} -noout -issuer \
        | grep -iPo 'O\s*=\s*\K[^,]+' \
        | sed -E "s/\s/_/g;s/'//g;s/\/.*//g;s/\*\.//g;s/.*/\U&/";
    done;) | sort -u)

  for ca in ${ca_list}; do
    echo -e "\n-> Generating p11-kit source anchors for CA \"${ca}\""
    local out=pki/ca-trust-source/anchors/${ca,,}-ca-bundle.crt
    mkdir -p $(dirname ${out}); in=
    for c in $(find certs/{ca-root,ca-trust,servers}/ -name ${ca}*); do
      echo "+ Loading CA certificate: ${c}"
      in="${in} -certfile ${c}"
    done \
      && openssl crl2pkcs7 -nocrl ${in} \
        | openssl pkcs7 -print_certs -out ${out}
  done
}

cmd=${@:1}; shift
${cmd} ${@}

exit 0

# vim: ts=2:sw=2:sts=2:et