cmdline/apt-key

   1 #!/bin/sh
   2
   3 set -e
   4 unset GREP_OPTIONS
   5
   6 # We don't use a secret keyring, of course, but gpg panics and
   7 # implodes if there isn't one available
   8 SECRETKEYRING="$(mktemp)"
   9 trap "rm -f '${SECRETKEYRING}'" 0 HUP INT QUIT ILL ABRT FPE SEGV PIPE TERM
  10 GPG_CMD="gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring ${SECRETKEYRING}"
  11
  12 if [ "$(id -u)" -eq 0 ]; then
  13         # we could use a tmpfile here too, but creation of this tends to be time-consuming
  14         eval $(apt-config shell TRUSTDBDIR Dir::Etc/d)
  15         GPG_CMD="$GPG_CMD --trustdb-name ${TRUSTDBDIR}/trustdb.gpg"
  16 fi
  17
  18 GPG="$GPG_CMD"
  19
  20 MASTER_KEYRING=""
  21 ARCHIVE_KEYRING_URI=""
  22 #MASTER_KEYRING=/usr/share/keyrings/debian-master-keyring.gpg
  23 #ARCHIVE_KEYRING_URI=http://ftp.debian.org/debian/debian-archive-keyring.gpg
  24
  25 ARCHIVE_KEYRING=/usr/share/keyrings/debian-archive-keyring.gpg
  26 REMOVED_KEYS=/usr/share/keyrings/debian-archive-removed-keys.gpg
  27
  28 requires_root() {
  29         if [ "$(id -u)" -ne 0 ]; then
  30                 echo >&1 "ERROR: This command can only be used by root."
  31                 exit 1
  32         fi
  33 }
  34
  35 # gpg defaults to mode 0600 for new keyrings. Create one with 0644 instead.
  36 init_keyring() {
  37     for path; do
  38         if ! [ -e "$path" ]; then
  39             touch -- "$path"
  40             chmod 0644 -- "$path"
  41         fi
  42     done
  43 }
  44
  45 add_keys_with_verify_against_master_keyring() {
  46     ADD_KEYRING=$1
  47     MASTER=$2
  48
  49     if [ ! -f "$ADD_KEYRING" ]; then
  50         echo "ERROR: '$ADD_KEYRING' not found"
  51         return
  52     fi
  53     if [ ! -f "$MASTER" ]; then
  54         echo "ERROR: '$MASTER' not found"
  55         return
  56     fi
  57
  58     # when adding new keys, make sure that the archive-master-keyring
  59     # is honored. so:
  60     #   all keys that are exported must have a valid signature
  61     #   from a key in the $distro-master-keyring
  62     add_keys=`$GPG_CMD --keyring $ADD_KEYRING --with-colons --list-keys | grep ^pub | cut -d: -f5`
  63     master_keys=`$GPG_CMD --keyring $MASTER --with-colons --list-keys | grep ^pub | cut -d: -f5`
  64     for add_key in $add_keys; do
  65         ADDED=0
  66         for master_key in $master_keys; do
  67             if $GPG_CMD --keyring $ADD_KEYRING --list-sigs --with-colons $add_key | grep ^sig | cut -d: -f5 | grep -q $master_key; then
  68                 $GPG_CMD --quiet --batch --keyring $ADD_KEYRING --export $add_key | $GPG --import
  69                 ADDED=1
  70             fi
  71         done
  72         if [ $ADDED = 0 ]; then
  73             echo >&2 "Key '$add_key' not added. It is not signed with a master key"
  74         fi
  75     done
  76 }
  77
  78 # update the current archive signing keyring from a network URI
  79 # the archive-keyring keys needs to be signed with the master key
  80 # (otherwise it does not make sense from a security POV)
  81 net_update() {
  82     if [ -z "$ARCHIVE_KEYRING_URI" ]; then
  83         echo >&2 "ERROR: Your distribution is not supported in net-update as no uri for the archive-keyring is set"
  84         exit 1
  85     fi
  86     requires_root
  87     # in theory we would need to depend on wget for this, but this feature
  88     # isn't useable in debian anyway as we have no keyring uri nor a master key
  89     if ! which wget >/dev/null 2>&1; then
  90         echo >&2 "ERROR: an installed wget is required for a network-based update"
  91         exit 1
  92     fi
  93     if [ ! -d /var/lib/apt/keyrings ]; then
  94         mkdir -p /var/lib/apt/keyrings
  95     fi
  96     keyring=/var/lib/apt/keyrings/$(basename $ARCHIVE_KEYRING)
  97     old_mtime=0
  98     if [ -e $keyring ]; then
  99         old_mtime=$(stat -c %Y $keyring)
 100     fi
 101     (cd  /var/lib/apt/keyrings; wget -q -N $ARCHIVE_KEYRING_URI)
 102     if [ ! -e $keyring ]; then
 103         return
 104     fi
 105     new_mtime=$(stat -c %Y $keyring)
 106     if [ $new_mtime -ne $old_mtime ]; then
 107         echo "Checking for new archive signing keys now"
 108         add_keys_with_verify_against_master_keyring $keyring $MASTER_KEYRING
 109     fi
 110 }
 111
 112 update() {
 113     if [ ! -f $ARCHIVE_KEYRING ]; then
 114         echo >&2 "ERROR: Can't find the archive-keyring"
 115         echo >&2 "Is the debian-archive-keyring package installed?"
 116         exit 1
 117     fi
 118     requires_root
 119
 120     # add new keys from the package;
 121
 122     # we do not use add_keys_with_verify_against_master_keyring here,
 123     # because "update" is run on regular package updates.  A
 124     # attacker might as well replace the master-archive-keyring file
 125     # in the package and add his own keys. so this check wouldn't
 126     # add any security. we *need* this check on net-update though
 127     $GPG_CMD --quiet --batch --keyring $ARCHIVE_KEYRING --export | $GPG --import
 128
 129     if [ -r "$REMOVED_KEYS" ]; then
 130         # remove no-longer supported/used keys
 131         keys=`$GPG_CMD --keyring $REMOVED_KEYS --with-colons --list-keys | grep ^pub | cut -d: -f5`
 132         for key in $keys; do
 133             if $GPG --list-keys --with-colons | grep ^pub | cut -d: -f5 | grep -q $key; then
 134                 $GPG --quiet --batch --delete-key --yes ${key}
 135             fi
 136         done
 137     else
 138         echo "Warning: removed keys keyring  $REMOVED_KEYS missing or not readable" >&2
 139     fi
 140 }
 141
 142
 143 usage() {
 144     echo "Usage: apt-key [--keyring file] [command] [arguments]"
 145     echo
 146     echo "Manage apt's list of trusted keys"
 147     echo
 148     echo "  apt-key add <file>          - add the key contained in <file> ('-' for stdin)"
 149     echo "  apt-key del <keyid>         - remove the key <keyid>"
 150     echo "  apt-key export <keyid>      - output the key <keyid>"
 151     echo "  apt-key exportall           - output all trusted keys"
 152     echo "  apt-key update              - update keys using the keyring package"
 153     echo "  apt-key net-update          - update keys using the network"
 154     echo "  apt-key list                - list keys"
 155     echo "  apt-key finger              - list fingerprints"
 156     echo "  apt-key adv                 - pass advanced options to gpg (download key)"
 157     echo
 158     echo "If no specific keyring file is given the command applies to all keyring files."
 159 }
 160
 161 # Determine on which keyring we want to work
 162 if [ "$1" = "--keyring" ]; then
 163         #echo "keyfile given"
 164         shift
 165         TRUSTEDFILE="$1"
 166         if [ -r "$TRUSTEDFILE" ] || [ "$2" = 'add' ] || [ "$2" = 'adv' ]; then
 167                 GPG="$GPG --keyring $TRUSTEDFILE --primary-keyring $TRUSTEDFILE"
 168         else
 169                 echo >&2 "Error: The specified keyring »$TRUSTEDFILE« is missing or not readable"
 170                 exit 1
 171         fi
 172         shift
 173 # otherwise use the default
 174 else
 175         #echo "generate list"
 176         TRUSTEDFILE="/etc/apt/trusted.gpg"
 177         eval $(apt-config shell TRUSTEDFILE Apt::GPGV::TrustedKeyring)
 178         eval $(apt-config shell TRUSTEDFILE Dir::Etc::Trusted/f)
 179         if [ -r "$TRUSTEDFILE" ]; then
 180                 GPG="$GPG --keyring $TRUSTEDFILE"
 181         fi
 182         GPG="$GPG --primary-keyring $TRUSTEDFILE"
 183         TRUSTEDPARTS="/etc/apt/trusted.gpg.d"
 184         eval $(apt-config shell TRUSTEDPARTS Dir::Etc::TrustedParts/d)
 185         if [ -d "$TRUSTEDPARTS" ]; then
 186                 #echo "parts active"
 187                 for trusted in $(run-parts --list $TRUSTEDPARTS --regex '^.*\.gpg$'); do
 188                         #echo "part -> $trusted"
 189                         GPG="$GPG --keyring $trusted"
 190                 done
 191         fi
 192 fi
 193 #echo "COMMAND: $GPG"
 194
 195 command="$1"
 196 if [ -z "$command" ]; then
 197     usage
 198     exit 1
 199 fi
 200 shift
 201
 202 if [ "$command" != "help" ] && ! which gpg >/dev/null 2>&1; then
 203     echo >&2 "Warning: gnupg does not seem to be installed."
 204     echo >&2 "Warning: apt-key requires gnupg for most operations."
 205     echo >&2
 206 fi
 207
 208 case "$command" in
 209     add)
 210         requires_root
 211         init_keyring "$TRUSTEDFILE"
 212         $GPG --quiet --batch --import "$1"
 213         echo "OK"
 214         ;;
 215     del|rm|remove)
 216         requires_root
 217         init_keyring "$TRUSTEDFILE"
 218         $GPG --quiet --batch --delete-key --yes "$1"
 219         echo "OK"
 220         ;;
 221     update)
 222         init_keyring "$TRUSTEDFILE"
 223         update
 224         ;;
 225     net-update)
 226         init_keyring "$TRUSTEDFILE"
 227         net_update
 228         ;;
 229     list)
 230         init_keyring "$TRUSTEDFILE"
 231         $GPG --batch --list-keys
 232         ;;
 233     finger*)
 234         init_keyring "$TRUSTEDFILE"
 235         $GPG --batch --fingerprint
 236         ;;
 237     export)
 238         init_keyring "$TRUSTEDFILE"
 239         $GPG --armor --export "$1"
 240         ;;
 241     exportall)
 242         init_keyring "$TRUSTEDFILE"
 243         $GPG --armor --export
 244         ;;
 245     adv*)
 246         init_keyring "$TRUSTEDFILE"
 247         echo "Executing: $GPG $*"
 248         $GPG $*
 249         ;;
 250     help)
 251         usage
 252         ;;
 253     *)
 254         usage
 255         exit 1
 256         ;;
 257 esac