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
   9 GPG_CMD="gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg"
  10 GPG="$GPG_CMD --keyring /etc/apt/trusted.gpg"
  11
  12
  13 MASTER_KEYRING=/usr/share/keyrings/ubuntu-master-keyring.gpg
  14 ARCHIVE_KEYRING=/usr/share/keyrings/ubuntu-archive-keyring.gpg
  15 REMOVED_KEYS=/usr/share/keyrings/ubuntu-archive-removed-keys.gpg
  16 ARCHIVE_KEYRING_URI=http://archive.ubuntu.com/ubuntu/project/ubuntu-archive-keyring.gpg
  17
  18 add_keys_with_verify_against_master_keyring() {
  19     ADD_KEYRING=$1
  20     MASTER=$2
  21
  22     if [ ! -f "$ADD_KEYRING" ]; then
  23         echo "ERROR: '$ADD_KEYRING' not found"
  24         return
  25     fi
  26     if [ ! -f "$MASTER" ]; then
  27         echo "ERROR: '$MASTER' not found"
  28         return
  29     fi
  30
  31     # when adding new keys, make sure that the archive-master-keyring
  32     # is honored. so:
  33     #   all keys that are exported must have a valid signature
  34     #   from a key in the $distro-master-keyring
  35     add_keys=`$GPG_CMD --keyring $ADD_KEYRING --with-colons --list-keys | grep ^pub | cut -d: -f5`
  36     master_keys=`$GPG_CMD --keyring $MASTER --with-colons --list-keys | grep ^pub | cut -d: -f5`
  37     for add_key in $add_keys; do
  38         ADDED=0
  39         for master_key in $master_keys; do
  40             if $GPG_CMD --keyring $ADD_KEYRING --list-sigs --with-colons $add_key | grep ^sig | cut -d: -f5 | grep -q $master_key; then
  41                 $GPG_CMD --quiet --batch --keyring $ADD_KEYRING --export $add_key | $GPG --import
  42                 ADDED=1
  43             fi
  44         done
  45         if [ $ADDED = 0 ]; then
  46             echo >&2 "Key '$add_key' not added. It is not signed with a master key"
  47         fi
  48     done
  49 }
  50
  51 # update the current archive signing keyring from a network URI
  52 # the archive-keyring keys needs to be signed with the master key
  53 # (otherwise it does not make sense from a security POV)
  54 net_update() {
  55     if [ -z "$ARCHIVE_KEYRING_URI" ]; then
  56         echo "ERROR: no location for the archive-keyring given"
  57     fi
  58     if [ ! -d /var/lib/apt/keyrings ]; then
  59         mkdir -p /var/lib/apt/keyrings
  60     fi
  61     keyring=/var/lib/apt/keyrings/$(basename $ARCHIVE_KEYRING)
  62     old_mtime=0
  63     if [ -e $keyring ]; then
  64         old_mtime=$(stat -c %Y $keyring)
  65     fi
  66     (cd  /var/lib/apt/keyrings; wget -q -N $ARCHIVE_KEYRING_URI)
  67     if [ ! -e $keyring ]; then
  68         return
  69     fi
  70     new_mtime=$(stat -c %Y $keyring)
  71     if [ $new_mtime -ne $old_mtime ]; then
  72         echo "Checking for new archive signing keys now"
  73         add_keys_with_verify_against_master_keyring $keyring $MASTER_KEYRING
  74     fi
  75 }
  76
  77 update() {
  78     if [ ! -f $ARCHIVE_KEYRING ]; then
  79         echo >&2 "ERROR: Can't find the archive-keyring"
  80         echo >&2 "Is the ubuntu-keyring package installed?"
  81         exit 1
  82     fi
  83
  84     # add new keys from the package;
  85
  86     # we do not use add_keys_with_verify_against_master_keyring here,
  87     # because we "update" is run on regular package updates.  A
  88     # attacker might as well replace the master-archive-keyring file
  89     # in the package and add his own keys. so this check wouldn't
  90     # add any security. we *need* this check on net-update though
  91     $GPG_CMD --quiet --batch --keyring $ARCHIVE_KEYRING --export | $GPG --import
  92
  93     if [ -r "$REMOVED_KEYS" ]; then
  94         # remove no-longer supported/used keys
  95         keys=`$GPG_CMD --keyring $REMOVED_KEYS --with-colons --list-keys | grep ^pub | cut -d: -f5`
  96         for key in $keys; do
  97             if $GPG --list-keys --with-colons | grep ^pub | cut -d: -f5 | grep -q $key; then
  98                 $GPG --quiet --batch --delete-key --yes ${key}
  99             fi
 100         done
 101     else
 102         echo "Warning: removed keys keyring  $REMOVED_KEYS missing or not readable" >&2
 103     fi
 104 }
 105
 106
 107 usage() {
 108     echo "Usage: apt-key [command] [arguments]"
 109     echo
 110     echo "Manage apt's list of trusted keys"
 111     echo
 112     echo "  apt-key add <file>          - add the key contained in <file> ('-' for stdin)"
 113     echo "  apt-key del <keyid>         - remove the key <keyid>"
 114     echo "  apt-key export <keyid>      - output the key <keyid>"
 115     echo "  apt-key exportall           - output all trusted keys"
 116     echo "  apt-key update              - update keys using the keyring package"
 117     echo "  apt-key net-update          - update keys using the network"
 118     echo "  apt-key list                - list keys"
 119     echo "  apt-key finger              - list fingerprints"
 120     echo "  apt-key adv                 - pass advanced options to gpg (download key)"
 121     echo
 122 }
 123
 124 command="$1"
 125 if [ -z "$command" ]; then
 126     usage
 127     exit 1
 128 fi
 129 shift
 130
 131 if [ "$command" != "help" ] && ! which gpg >/dev/null 2>&1; then
 132     echo >&2 "Warning: gnupg does not seem to be installed."
 133     echo >&2 "Warning: apt-key requires gnupg for most operations."
 134     echo >&2
 135 fi
 136
 137 case "$command" in
 138     add)
 139         $GPG --quiet --batch --import "$1"
 140         echo "OK"
 141         ;;
 142     del|rm|remove)
 143         $GPG --quiet --batch --delete-key --yes "$1"
 144         echo "OK"
 145         ;;
 146     update)
 147         update
 148         ;;
 149     net-update)
 150         net_update
 151         ;;
 152     list)
 153         $GPG --batch --list-keys
 154         ;;
 155     finger*)
 156         $GPG --batch --fingerprint
 157         ;;
 158     export)
 159         $GPG --armor --export "$1"
 160         ;;
 161     exportall)
 162         $GPG --armor --export
 163         ;;
 164     adv*)
 165         echo "Executing: $GPG $*"
 166         $GPG $*
 167         ;;
 168     help)
 169         usage
 170         ;;
 171     *)
 172         usage
 173         exit 1
 174         ;;
 175 esac