cmdline/apt-key.in

   1 #!/bin/sh
   2
   3 set -e
   4 unset GREP_OPTIONS
   5 export IFS="$(printf "\n\b")"
   6
   7 MASTER_KEYRING='&keyring-master-filename;'
   8 eval "$(apt-config shell MASTER_KEYRING APT::Key::MasterKeyring)"
   9 ARCHIVE_KEYRING='&keyring-filename;'
  10 eval "$(apt-config shell ARCHIVE_KEYRING APT::Key::ArchiveKeyring)"
  11 REMOVED_KEYS='&keyring-removed-filename;'
  12 eval "$(apt-config shell REMOVED_KEYS APT::Key::RemovedKeys)"
  13 ARCHIVE_KEYRING_URI='&keyring-uri;'
  14 eval "$(apt-config shell ARCHIVE_KEYRING_URI APT::Key::ArchiveKeyringURI)"
  15
  16 aptkey_echo() { echo "$@"; }
  17
  18 requires_root() {
  19         if [ "$(id -u)" -ne 0 ]; then
  20                 echo >&2 "ERROR: This command can only be used by root."
  21                 exit 1
  22         fi
  23 }
  24
  25 command_available() {
  26     # command -v "$1" >/dev/null 2>&1 # not required by policy, see #747320
  27     # which "$1" >/dev/null 2>&1 # is in debianutils (essential) but not on non-debian systems
  28     local OLDIFS="$IFS"
  29     IFS=:
  30     for p in $PATH; do
  31         if [ -x "${p}/${1}" ]; then
  32             IFS="$OLDIFS"
  33             return 0
  34         fi
  35     done
  36     IFS="$OLDIFS"
  37     return 1
  38 }
  39
  40 escape_shell() {
  41     echo "$@" | sed -e "s#'#'\"'\"'#g"
  42 }
  43
  44 get_fingerprints_of_keyring() {
  45     aptkey_execute "$GPG_SH" --keyring "$1" --with-colons --fingerprint | while read publine; do
  46         # search for a public key
  47         if [ "${publine%%:*}" != 'pub' ]; then continue; fi
  48         # search for the associated fingerprint (should be the very next line)
  49         while read fprline; do
  50            if [ "${fprline%%:*}" = 'sub' ]; then break; # should never happen
  51            elif [ "${fprline%%:*}" != 'fpr' ]; then continue; fi
  52            echo "$fprline" | cut -d':' -f 10
  53         done
  54         # order in the keyring shouldn't be important
  55     done | sort
  56 }
  57
  58 add_keys_with_verify_against_master_keyring() {
  59     ADD_KEYRING="$1"
  60     MASTER="$2"
  61
  62     if [ ! -f "$ADD_KEYRING" ]; then
  63         echo >&2 "ERROR: '$ADD_KEYRING' not found"
  64         return
  65     fi
  66     if [ ! -f "$MASTER" ]; then
  67         echo >&2 "ERROR: '$MASTER' not found"
  68         return
  69     fi
  70
  71     # when adding new keys, make sure that the archive-master-keyring
  72     # is honored. so:
  73     #   all keys that are exported must have a valid signature
  74     #   from a key in the $distro-master-keyring
  75     add_keys="$(get_fingerprints_of_keyring "$ADD_KEYRING")"
  76     all_add_keys="$(aptkey_execute "$GPG_SH" --keyring "$ADD_KEYRING" --with-colons --list-keys | grep ^[ps]ub | cut -d: -f5)"
  77     master_keys="$(aptkey_execute "$GPG_SH" --keyring "$MASTER" --with-colons --list-keys | grep ^pub | cut -d: -f5)"
  78
  79     # ensure there are no colisions LP: #857472
  80     for all_add_key in $all_add_keys; do
  81         for master_key in $master_keys; do
  82             if [ "$all_add_key" = "$master_key" ]; then
  83                 echo >&2 "Keyid collision for '$all_add_key' detected, operation aborted"
  84                 return 1
  85             fi
  86         done
  87     done
  88
  89     for add_key in $add_keys; do
  90         # export the add keyring one-by-one
  91         local TMP_KEYRING="${GPGHOMEDIR}/tmp-keyring.gpg"
  92         aptkey_execute "$GPG_SH" --batch --yes --keyring "$ADD_KEYRING" --output "$TMP_KEYRING" --export "$add_key"
  93         if ! aptkey_execute "$GPG_SH" --batch --yes --keyring "$TMP_KEYRING" --import "$MASTER" > "${GPGHOMEDIR}/gpgoutput.log" 2>&1; then
  94             cat >&2 "${GPGHOMEDIR}/gpgoutput.log"
  95             false
  96         fi
  97         # check if signed with the master key and only add in this case
  98         ADDED=0
  99         for master_key in $master_keys; do
 100             if aptkey_execute "$GPG_SH" --keyring "$TMP_KEYRING" --check-sigs --with-colons "$add_key" \
 101                | grep '^sig:!:' | cut -d: -f5 | grep -q "$master_key"; then
 102                 aptkey_execute "$GPG_SH" --batch --yes --keyring "$ADD_KEYRING" --export "$add_key" \
 103                    | aptkey_execute "$GPG" --batch --yes --import
 104                 ADDED=1
 105             fi
 106         done
 107         if [ $ADDED = 0 ]; then
 108             echo >&2 "Key '$add_key' not added. It is not signed with a master key"
 109         fi
 110         rm -f "${TMP_KEYRING}"
 111     done
 112 }
 113
 114 # update the current archive signing keyring from a network URI
 115 # the archive-keyring keys needs to be signed with the master key
 116 # (otherwise it does not make sense from a security POV)
 117 net_update() {
 118     local APT_DIR='/'
 119     eval $(apt-config shell APT_DIR Dir)
 120
 121     # Disabled for now as code is insecure (LP: #1013639 (and 857472, 1013128))
 122     APT_KEY_NET_UPDATE_ENABLED=""
 123     eval $(apt-config shell APT_KEY_NET_UPDATE_ENABLED APT::Key::Net-Update-Enabled)
 124     if [ -z "$APT_KEY_NET_UPDATE_ENABLED" ]; then
 125         exit 1
 126     fi
 127
 128     if [ -z "$ARCHIVE_KEYRING_URI" ]; then
 129         echo >&2 "ERROR: Your distribution is not supported in net-update as no uri for the archive-keyring is set"
 130         exit 1
 131     fi
 132     # in theory we would need to depend on wget for this, but this feature
 133     # isn't useable in debian anyway as we have no keyring uri nor a master key
 134     if ! command_available 'wget'; then
 135         echo >&2 "ERROR: an installed wget is required for a network-based update"
 136         exit 1
 137     fi
 138     if [ ! -d "${APT_DIR}/var/lib/apt/keyrings" ]; then
 139         mkdir -p "${APT_DIR}/var/lib/apt/keyrings"
 140     fi
 141     keyring="${APT_DIR}/var/lib/apt/keyrings/$(basename "$ARCHIVE_KEYRING_URI")"
 142     old_mtime=0
 143     if [ -e $keyring ]; then
 144         old_mtime=$(stat -c %Y "$keyring")
 145     fi
 146     (cd  "${APT_DIR}/var/lib/apt/keyrings"; wget --timeout=90 -q -N "$ARCHIVE_KEYRING_URI")
 147     if [ ! -e "$keyring" ]; then
 148         return
 149     fi
 150     new_mtime=$(stat -c %Y "$keyring")
 151     if [ $new_mtime -ne $old_mtime ]; then
 152         aptkey_echo "Checking for new archive signing keys now"
 153         add_keys_with_verify_against_master_keyring "$keyring" "$MASTER_KEYRING"
 154     fi
 155 }
 156
 157 update() {
 158     if [ ! -f "$ARCHIVE_KEYRING" ]; then
 159         echo >&2 "ERROR: Can't find the archive-keyring"
 160         echo >&2 "Is the &keyring-package; package installed?"
 161         exit 1
 162     fi
 163
 164     # add new keys from the package;
 165
 166     # we do not use add_keys_with_verify_against_master_keyring here,
 167     # because "update" is run on regular package updates.  A
 168     # attacker might as well replace the master-archive-keyring file
 169     # in the package and add his own keys. so this check wouldn't
 170     # add any security. we *need* this check on net-update though
 171     import_keyring_into_keyring "$ARCHIVE_KEYRING" '' && cat "${GPGHOMEDIR}/gpgoutput.log"
 172
 173     if [ -r "$REMOVED_KEYS" ]; then
 174         # remove no-longer supported/used keys
 175         get_fingerprints_of_keyring "$REMOVED_KEYS" | while read key; do
 176             foreach_keyring_do 'remove_key_from_keyring' "$key"
 177         done
 178     else
 179         echo >&2 "Warning: removed keys keyring  $REMOVED_KEYS missing or not readable"
 180     fi
 181 }
 182
 183 remove_key_from_keyring() {
 184     local KEYRINGFILE="$1"
 185     shift
 186     # non-existent keyrings have by definition no keys
 187     if [ ! -e "$KEYRINGFILE" ]; then
 188        return
 189     fi
 190
 191     for KEY in "$@"; do
 192         local FINGERPRINTS="${GPGHOMEDIR}/keyringfile.keylst"
 193         get_fingerprints_of_keyring "$KEYRINGFILE" > "$FINGERPRINTS"
 194
 195         # strip leading 0x, if present:
 196         KEY="${KEY#0x}"
 197
 198         # check if the key is in this keyring
 199         if ! grep -iq "^[0-9A-F]*${KEY}$" "$FINGERPRINTS"; then
 200             continue
 201         fi
 202         if [ ! -w "$KEYRINGFILE" ]; then
 203             echo >&2 "Key ${KEY} is in keyring ${KEYRINGFILE}, but can't be removed as it is read only."
 204             continue
 205         fi
 206         # check if it is the only key in the keyring and if so remove the keyring altogether
 207         if [ '1' = "$(uniq "$FINGERPRINTS" | wc -l)" ]; then
 208             mv -f "$KEYRINGFILE" "${KEYRINGFILE}~" # behave like gpg
 209             return
 210         fi
 211         # we can't just modify pointed to files as these might be in /usr or something
 212         local REALTARGET
 213         if [ -L "$KEYRINGFILE" ]; then
 214             REALTARGET="$(readlink -f "$KEYRINGFILE")"
 215             mv -f "$KEYRINGFILE" "${KEYRINGFILE}.dpkg-tmp"
 216             cp -a "$REALTARGET" "$KEYRINGFILE"
 217         fi
 218         # delete the key from the keyring
 219         aptkey_execute "$GPG_SH" --keyring "$KEYRINGFILE" --batch --delete-keys --yes "$KEY"
 220         if [ -n "$REALTARGET" ]; then
 221             # the real backup is the old link, not the copy we made
 222             mv -f "${KEYRINGFILE}.dpkg-tmp" "${KEYRINGFILE}~"
 223         fi
 224     done
 225 }
 226
 227 foreach_keyring_do() {
 228    local ACTION="$1"
 229    shift
 230    # if a --keyring was given, just work on this one
 231    if [ -n "$FORCED_KEYRING" ]; then
 232         $ACTION "$FORCED_KEYRING" "$@"
 233    else
 234         # otherwise all known keyrings are up for inspection
 235         if [ -s "$TRUSTEDFILE" ]; then
 236             $ACTION "$TRUSTEDFILE" "$@"
 237         fi
 238         local TRUSTEDPARTS="/etc/apt/trusted.gpg.d"
 239         eval "$(apt-config shell TRUSTEDPARTS Dir::Etc::TrustedParts/d)"
 240         if [ -d "$TRUSTEDPARTS" ]; then
 241             # strip / suffix as gpg will double-slash in that case (#665411)
 242             local STRIPPED_TRUSTEDPARTS="${TRUSTEDPARTS%/}"
 243             if [ "${STRIPPED_TRUSTEDPARTS}/" = "$TRUSTEDPARTS" ]; then
 244                 TRUSTEDPARTS="$STRIPPED_TRUSTEDPARTS"
 245             fi
 246             for trusted in $(find "$TRUSTEDPARTS" -mindepth 1 -maxdepth 1 -regex '^.*\.gpg$' | sort); do
 247                 if [ -s "$trusted" ]; then
 248                     $ACTION "$trusted" "$@"
 249                 fi
 250             done
 251         fi
 252    fi
 253 }
 254
 255 run_cmd_on_keyring() {
 256     local KEYRINGFILE="$1"
 257     shift
 258     # fingerprint and co will fail if key isn't in this keyring
 259     aptkey_execute "$GPG_SH" --keyring "$KEYRINGFILE" --batch "$@" 2>/dev/null || true
 260 }
 261
 262 import_keyring_into_keyring() {
 263     local FROM="${1:-${GPGHOMEDIR}/pubring.gpg}"
 264     local TO="${2:-${GPGHOMEDIR}/pubring.gpg}"
 265     shift 2
 266     rm -f "${GPGHOMEDIR}/gpgoutput.log"
 267     # the idea is simple: We take keys from one keyring and copy it to another
 268     # we do this with so many checks in between to ensure that WE control the
 269     # creation, so we know that the (potentially) created $TO keyring is a
 270     # simple keyring rather than a keybox as gpg2 would create it which in turn
 271     # can't be read by gpgv.
 272     # BEWARE: This is designed more in the way to work with the current
 273     # callers, than to have a well defined it would be easy to add new callers to.
 274     if [ ! -s "$TO" ]; then
 275         if [ -s "$FROM" ]; then
 276             if [ -z "$2" ]; then
 277                 if ! aptkey_execute "$GPG_SH" --keyring "$FROM" --export ${1:+"$1"} > "$TO" 2> "${GPGHOMEDIR}/gpgoutput.log"; then
 278                     cat >&2 "${GPGHOMEDIR}/gpgoutput.log"
 279                     false
 280                 else
 281                     chmod 0644 -- "$TO"
 282                 fi
 283             else
 284                 create_new_keyring "$TO"
 285             fi
 286         else
 287             create_new_keyring "$TO"
 288         fi
 289     elif [ -s "$FROM" ]; then
 290         local EXPORTLIMIT="$1"
 291         if [ -n "$1$2" ]; then shift; fi
 292         if ! aptkey_execute "$GPG_SH" --keyring "$FROM" --export ${EXPORTLIMIT:+"$EXPORTLIMIT"} \
 293            | aptkey_execute "$GPG_SH" --keyring "$TO" --batch --import "$@" > "${GPGHOMEDIR}/gpgoutput.log" 2>&1; then
 294             cat >&2 "${GPGHOMEDIR}/gpgoutput.log"
 295             false
 296         fi
 297     fi
 298 }
 299
 300 merge_all_trusted_keyrings_into_pubring() {
 301     # does the same as:
 302     # foreach_keyring_do 'import_keys_from_keyring' "${GPGHOMEDIR}/pubring.gpg"
 303     # but without using gpg, just cat and find
 304     local PUBRING="${GPGHOMEDIR}/pubring.gpg"
 305     # if a --keyring was given, just use this one
 306     if [ -n "$FORCED_KEYRING" ]; then
 307         if [ -s "$FORCED_KEYRING" ]; then
 308             cp --dereference "$FORCED_KEYRING" "$PUBRING"
 309         fi
 310     else
 311         # otherwise all known keyrings are merged
 312         local TRUSTEDPARTS="/etc/apt/trusted.gpg.d"
 313         eval $(apt-config shell TRUSTEDPARTS Dir::Etc::TrustedParts/d)
 314         if [ -d "$TRUSTEDPARTS" ]; then
 315             # ignore errors mostly for non-existing $TRUSTEDFILE
 316             {
 317                cat "$TRUSTEDFILE" || true
 318                for parts in $(find -L "$TRUSTEDPARTS" -type f -name '*.gpg'); do
 319                   cat "$parts" || true
 320                done
 321             } > "$PUBRING" 2>/dev/null
 322         elif [ -s "$TRUSTEDFILE" ]; then
 323             cp --dereference "$TRUSTEDFILE" "$PUBRING"
 324         fi
 325     fi
 326
 327     if [ ! -s "$PUBRING" ]; then
 328         touch "$PUBRING"
 329     fi
 330 }
 331
 332 import_keys_from_keyring() {
 333     import_keyring_into_keyring "$1" "$2"
 334 }
 335
 336 merge_keys_into_keyrings() {
 337     import_keyring_into_keyring "$2" "$1" '' --import-options 'merge-only'
 338 }
 339
 340 merge_back_changes() {
 341     if [ -n "$FORCED_KEYRING" ]; then
 342         # if the keyring was forced merge is already done
 343         return
 344     fi
 345     if [ -s "${GPGHOMEDIR}/pubring.gpg" ]; then
 346         # merge all updated keys
 347         foreach_keyring_do 'merge_keys_into_keyrings' "${GPGHOMEDIR}/pubring.gpg"
 348     fi
 349     # look for keys which were added or removed
 350     get_fingerprints_of_keyring "${GPGHOMEDIR}/pubring.orig.gpg" > "${GPGHOMEDIR}/pubring.orig.keylst"
 351     get_fingerprints_of_keyring "${GPGHOMEDIR}/pubring.gpg" > "${GPGHOMEDIR}/pubring.keylst"
 352     comm -3 "${GPGHOMEDIR}/pubring.keylst" "${GPGHOMEDIR}/pubring.orig.keylst" > "${GPGHOMEDIR}/pubring.diff"
 353     # key isn't part of new keyring, so remove
 354     cut -f 2 "${GPGHOMEDIR}/pubring.diff" | while read key; do
 355         if [ -z "$key" ]; then continue; fi
 356         foreach_keyring_do 'remove_key_from_keyring' "$key"
 357     done
 358     # key is only part of new keyring, so we need to import it
 359     cut -f 1 "${GPGHOMEDIR}/pubring.diff" | while read key; do
 360         if [ -z "$key" ]; then continue; fi
 361         import_keyring_into_keyring '' "$TRUSTEDFILE" "$key"
 362     done
 363 }
 364
 365 setup_merged_keyring() {
 366     if [ -n "$FORCED_KEYID" ]; then
 367         merge_all_trusted_keyrings_into_pubring
 368         FORCED_KEYRING="${GPGHOMEDIR}/forcedkeyid.gpg"
 369         TRUSTEDFILE="${FORCED_KEYRING}"
 370         echo "#!/bin/sh
 371 exec sh '($(escape_shell "${GPG}")' --keyring '$(escape_shell "${TRUSTEDFILE}")' \"\$@\"" > "${GPGHOMEDIR}/gpg.1.sh"
 372         GPG="${GPGHOMEDIR}/gpg.1.sh"
 373         # ignore error as this "just" means we haven't found the forced keyid and the keyring will be empty
 374         import_keyring_into_keyring '' "$TRUSTEDFILE" "$FORCED_KEYID" || true
 375     elif [ -z "$FORCED_KEYRING" ]; then
 376         merge_all_trusted_keyrings_into_pubring
 377         if [ -r "${GPGHOMEDIR}/pubring.gpg" ]; then
 378             cp -a "${GPGHOMEDIR}/pubring.gpg" "${GPGHOMEDIR}/pubring.orig.gpg"
 379         else
 380            touch "${GPGHOMEDIR}/pubring.gpg" "${GPGHOMEDIR}/pubring.orig.gpg"
 381         fi
 382         echo "#!/bin/sh
 383 exec sh '$(escape_shell "${GPG}")' --keyring '$(escape_shell "${GPGHOMEDIR}/pubring.gpg")' \"\$@\"" > "${GPGHOMEDIR}/gpg.1.sh"
 384         GPG="${GPGHOMEDIR}/gpg.1.sh"
 385     else
 386         create_new_keyring "$TRUSTEDFILE"
 387         echo "#!/bin/sh
 388 exec sh '$(escape_shell "${GPG}")' --keyring '$(escape_shell "${TRUSTEDFILE}")' \"\$@\"" > "${GPGHOMEDIR}/gpg.1.sh"
 389         GPG="${GPGHOMEDIR}/gpg.1.sh"
 390     fi
 391 }
 392
 393 create_new_keyring() {
 394     # gpg defaults to mode 0600 for new keyrings. Create one with 0644 instead.
 395     if ! [ -e "$TRUSTEDFILE" ]; then
 396         if [ -w "$(dirname "$TRUSTEDFILE")" ]; then
 397             touch -- "$TRUSTEDFILE"
 398             chmod 0644 -- "$TRUSTEDFILE"
 399         fi
 400     fi
 401 }
 402
 403 aptkey_execute() { sh "$@"; }
 404
 405 usage() {
 406     echo "Usage: apt-key [--keyring file] [command] [arguments]"
 407     echo
 408     echo "Manage apt's list of trusted keys"
 409     echo
 410     echo "  apt-key add <file>          - add the key contained in <file> ('-' for stdin)"
 411     echo "  apt-key del <keyid>         - remove the key <keyid>"
 412     echo "  apt-key export <keyid>      - output the key <keyid>"
 413     echo "  apt-key exportall           - output all trusted keys"
 414     echo "  apt-key update              - update keys using the keyring package"
 415     echo "  apt-key net-update          - update keys using the network"
 416     echo "  apt-key list                - list keys"
 417     echo "  apt-key finger              - list fingerprints"
 418     echo "  apt-key adv                 - pass advanced options to gpg (download key)"
 419     echo
 420     echo "If no specific keyring file is given the command applies to all keyring files."
 421 }
 422
 423 while [ -n "$1" ]; do
 424    case "$1" in
 425       --keyring)
 426          shift
 427          TRUSTEDFILE="$1"
 428          FORCED_KEYRING="$1"
 429          ;;
 430       --keyid)
 431          shift
 432          FORCED_KEYID="$1"
 433          ;;
 434       --secret-keyring)
 435          shift
 436          FORCED_SECRET_KEYRING="$1"
 437          ;;
 438       --readonly)
 439          merge_back_changes() { true; }
 440          create_new_keyring() { if [ ! -r "$FORCED_KEYRING" ]; then TRUSTEDFILE='/dev/null'; FORCED_KEYRING="$TRUSTEDFILE"; fi; }
 441          ;;
 442       --fakeroot)
 443          requires_root() { true; }
 444          ;;
 445       --quiet)
 446          aptkey_echo() { true; }
 447          ;;
 448       --debug1)
 449          # some cmds like finger redirect stderr to /dev/null …
 450         aptkey_execute() { echo 'EXEC:' "$@"; sh "$@"; }
 451         ;;
 452       --debug2)
 453          # … other more complicated ones pipe gpg into gpg.
 454         aptkey_execute() { echo >&2 'EXEC:' "$@"; sh "$@"; }
 455         ;;
 456       --*)
 457          echo >&2 "Unknown option: $1"
 458          usage
 459          exit 1;;
 460       *)
 461          break;;
 462    esac
 463    shift
 464 done
 465
 466 if [ -z "$TRUSTEDFILE" ]; then
 467    TRUSTEDFILE="/etc/apt/trusted.gpg"
 468    eval $(apt-config shell TRUSTEDFILE Apt::GPGV::TrustedKeyring)
 469    eval $(apt-config shell TRUSTEDFILE Dir::Etc::Trusted/f)
 470 fi
 471
 472 command="$1"
 473 if [ -z "$command" ]; then
 474     usage
 475     exit 1
 476 fi
 477 shift
 478
 479 create_gpg_home() {
 480     # gpg needs (in different versions more or less) files to function correctly,
 481     # so we give it its own homedir and generate some valid content for it later on
 482     if [ -n "$TMPDIR" ]; then
 483         # tmpdir is a directory and current user has rwx access to it
 484         # same tests as in apt-pkg/contrib/fileutl.cc GetTempDir()
 485         if [ ! -d "$TMPDIR" ] || [ ! -r "$TMPDIR" ] || [ ! -w "$TMPDIR" ] || [ ! -x "$TMPDIR" ]; then
 486             unset TMPDIR
 487         fi
 488     fi
 489     GPGHOMEDIR="$(mktemp -d)"
 490     CURRENTTRAP="${CURRENTTRAP} rm -rf '$(escape_shell "${GPGHOMEDIR}")';"
 491     trap "${CURRENTTRAP}" 0 HUP INT QUIT ILL ABRT FPE SEGV PIPE TERM
 492     chmod 700 "$GPGHOMEDIR"
 493 }
 494
 495 prepare_gpg_home() {
 496     eval "$(apt-config shell GPG_EXE Apt::Key::gpgcommand)"
 497
 498     if [ -n "$GPG_EXE" ] && command_available "$GPG_EXE"; then
 499         true
 500     elif command_available 'gpg'; then
 501         GPG_EXE="gpg"
 502     elif command_available 'gpg2'; then
 503         GPG_EXE="gpg2"
 504     else
 505         echo >&2 "Error: gnupg or gnupg2 do not seem to be installed,"
 506         echo >&2 "Error: but apt-key requires gnupg or gnupg2 for this operation."
 507         echo >&2
 508         exit 255
 509     fi
 510
 511     create_gpg_home
 512
 513     # create the trustdb with an (empty) dummy keyring
 514     # older gpgs required it, newer gpgs even warn that it isn't needed,
 515     # but require it nonetheless for some commands, so we just play safe
 516     # here for the foreseeable future and create a dummy one
 517     touch "${GPGHOMEDIR}/empty.gpg"
 518     if ! "$GPG_EXE" --ignore-time-conflict --no-options --no-default-keyring \
 519        --homedir "$GPGHOMEDIR" --quiet --check-trustdb --keyring "${GPGHOMEDIR}/empty.gpg" >"${GPGHOMEDIR}/gpgoutput.log" 2>&1; then
 520        cat >&2 "${GPGHOMEDIR}/gpgoutput.log"
 521        false
 522     fi
 523
 524     # now tell gpg that it shouldn't try to maintain this trustdb file
 525     echo "#!/bin/sh
 526 exec '$(escape_shell "${GPG_EXE}")' --ignore-time-conflict --no-options --no-default-keyring \\
 527 --homedir '$(escape_shell "${GPGHOMEDIR}")' --no-auto-check-trustdb --trust-model always \"\$@\"" > "${GPGHOMEDIR}/gpg.0.sh"
 528     GPG_SH="${GPGHOMEDIR}/gpg.0.sh"
 529     GPG="$GPG_SH"
 530
 531     # We don't usually need a secret keyring, of course, but
 532     # for advanced operations, we might really need a secret keyring after all
 533     if [ -n "$FORCED_SECRET_KEYRING" ] && [ -r "$FORCED_SECRET_KEYRING" ]; then
 534         if ! aptkey_execute "$GPG" -v --batch --import "$FORCED_SECRET_KEYRING" >"${GPGHOMEDIR}/gpgoutput.log" 2>&1; then
 535             cat >&2 "${GPGHOMEDIR}/gpgoutput.log"
 536             false
 537         fi
 538     else
 539        # and then, there are older versions of gpg which panic and implode
 540        # if there isn't one available - and writeable for imports
 541        # and even if not output is littered with the creation of a secring,
 542        # so lets call import once to have it create what it wants in silence
 543        echo -n | aptkey_execute "$GPG" --batch --import >/dev/null 2>&1 || true
 544     fi
 545 }
 546
 547 if [ "$command" != 'help' ] && [ "$command" != 'verify' ]; then
 548     prepare_gpg_home
 549 fi
 550
 551 case "$command" in
 552     add)
 553         requires_root
 554         setup_merged_keyring
 555         aptkey_execute "$GPG" --quiet --batch --import "$@"
 556         merge_back_changes
 557         aptkey_echo "OK"
 558         ;;
 559     del|rm|remove)
 560         requires_root
 561         foreach_keyring_do 'remove_key_from_keyring' "$@"
 562         aptkey_echo "OK"
 563         ;;
 564     update)
 565         requires_root
 566         setup_merged_keyring
 567         update
 568         merge_back_changes
 569         ;;
 570     net-update)
 571         requires_root
 572         setup_merged_keyring
 573         net_update
 574         merge_back_changes
 575         ;;
 576     list)
 577         foreach_keyring_do 'run_cmd_on_keyring' --list-keys "$@"
 578         ;;
 579     finger*)
 580         foreach_keyring_do 'run_cmd_on_keyring' --fingerprint "$@"
 581         ;;
 582     export|exportall)
 583         merge_all_trusted_keyrings_into_pubring
 584         aptkey_execute "$GPG_SH" --keyring "${GPGHOMEDIR}/pubring.gpg" --armor --export "$@"
 585         ;;
 586     adv*)
 587         setup_merged_keyring
 588         aptkey_echo "Executing: $GPG $*"
 589         aptkey_execute "$GPG" "$@"
 590         merge_back_changes
 591         ;;
 592     verify)
 593         GPGV=''
 594         eval $(apt-config shell GPGV Apt::Key::gpgvcommand)
 595         if [ -n "$GPGV" ] && command_available "$GPGV"; then true;
 596         elif command_available 'gpgv'; then GPGV='gpgv';
 597         elif command_available 'gpgv2'; then GPGV='gpgv2';
 598         else
 599            echo >&2 'ERROR: gpgv or gpgv2 required for verification'
 600            exit 29
 601         fi
 602         # for a forced keyid we need gpg --export, so full wrapping required
 603         if [ -n "$FORCED_KEYID" ]; then
 604             prepare_gpg_home
 605         else
 606             create_gpg_home
 607         fi
 608         setup_merged_keyring
 609         if [ -n "$FORCED_KEYRING" ]; then
 610             "$GPGV" --homedir "${GPGHOMEDIR}" --keyring "${FORCED_KEYRING}" --ignore-time-conflict "$@"
 611         else
 612             "$GPGV" --homedir "${GPGHOMEDIR}" --keyring "${GPGHOMEDIR}/pubring.gpg" --ignore-time-conflict "$@"
 613         fi
 614         ;;
 615     help)
 616         usage
 617         ;;
 618     *)
 619         usage
 620         exit 1
 621         ;;
 622 esac