cmdline/apt-key

   1 #!/bin/sh
   2
   3 set -e
   4
   5 # We don't use a secret keyring, of course, but gpg panics and
   6 # implodes if there isn't one available
   7
   8 GPG_CMD="gpg --ignore-time-conflict --no-options --no-default-keyring --secret-keyring /etc/apt/secring.gpg --trustdb-name /etc/apt/trustdb.gpg"
   9 GPG="$GPG_CMD --keyring /etc/apt/trusted.gpg"
  10
  11
  12 MASTER_KEYRING=/usr/share/keyrings/ubuntu-master-keyring.gpg
  13 ARCHIVE_KEYRING=/usr/share/keyrings/ubuntu-archive-keyring.gpg
  14 REMOVED_KEYS=/usr/share/keyrings/ubuntu-archive-removed-keys.gpg
  15 ARCHIVE_KEYRING_URI=http://archive.ubuntu.com/ubuntu/project/ubuntu-archive-keyring.gpg
  16
  17 add_keys_with_verify_against_master_keyring() {
  18     ADD_KEYRING=$1
  19     MASTER=$2
  20
  21     if [ ! -f "$ADD_KEYRING" ]; then
  22         echo "ERROR: '$ADD_KEYRING' not found"
  23         return
  24     fi
  25     if [ ! -f "$MASTER" ]; then
  26         echo "ERROR: '$MASTER' not found"
  27         return
  28     fi
  29
  30     # when adding new keys, make sure that the archive-master-keyring
  31     # is honored. so:
  32     #   all keys that are exported must have a valid signature
  33     #   from a key in the $distro-master-keyring
  34     add_keys=`$GPG_CMD --keyring $ADD_KEYRING --with-colons --list-keys | grep ^pub | cut -d: -f5`
  35     master_keys=`$GPG_CMD --keyring $MASTER --with-colons --list-keys | grep ^pub | cut -d: -f5`
  36     for add_key in $add_keys; do
  37         ADDED=0
  38         for master_key in $master_keys; do
  39             if $GPG_CMD --keyring $ADD_KEYRING --list-sigs --with-colons $add_key | grep ^sig | cut -d: -f5 | grep -q $master_key; then
  40                 $GPG_CMD --quiet --batch --keyring $ADD_KEYRING --export $add_key | $GPG --import
  41                 ADDED=1
  42             fi
  43         done
  44         if [ $ADDED = 0 ]; then
  45             echo >&2 "Key '$add_key' not added. It is not signed with a master key"
  46         fi
  47     done
  48 }
  49
  50 # update the current archive signing keyring from a network URI
  51 # the archive-keyring keys needs to be signed with the master key
  52 # (otherwise it does not make sense from a security POV)
  53 net_update() {
  54     if [ -z "$ARCHIVE_KEYRING_URI" ]; then
  55         echo "ERROR: no location for the archive-keyring given"
  56     fi
  57     if [ ! -d /var/lib/apt/keyrings ]; then
  58         mkdir -p /var/lib/apt/keyrings
  59     fi
  60     keyring=/var/lib/apt/keyrings/$(basename $ARCHIVE_KEYRING)
  61     old_mtime=0
  62     if [ -e $keyring ]; then
  63         old_mtime=$(stat -c %Y $keyring)
  64     fi
  65     (cd  /var/lib/apt/keyrings; wget -q -N $ARCHIVE_KEYRING_URI)
  66     if [ ! -e $keyring ]; then
  67         return
  68     fi
  69     new_mtime=$(stat -c %Y $keyring)
  70     if [ $new_mtime -ne $old_mtime ]; then
  71         echo "Checking for new archive signing keys now"
  72         add_keys_with_verify_against_master_keyring $keyring $MASTER_KEYRING
  73     fi
  74 }
  75
  76 update() {
  77     if [ ! -f $ARCHIVE_KEYRING ]; then
  78         echo >&2 "ERROR: Can't find the archive-keyring"
  79         echo >&2 "Is the ubuntu-keyring package installed?"
  80         exit 1
  81     fi
  82
  83     # add new keys from the package;
  84
  85     # we do not use add_keys_with_verify_against_master_keyring here,
  86     # because we "update" is run on regular package updates.  A
  87     # attacker might as well replace the master-archive-keyring file
  88     # in the package and add his own keys. so this check wouldn't
  89     # add any security. we *need* this check on net-update though
  90     $GPG_CMD --quiet --batch --keyring $ARCHIVE_KEYRING --export | $GPG --import
  91
  92     # remove no-longer supported/used keys
  93     keys=`$GPG_CMD --keyring $REMOVED_KEYS --with-colons --list-keys | grep ^pub | cut -d: -f5`
  94     for key in $keys; do
  95         if $GPG --list-keys --with-colons | grep ^pub | cut -d: -f5 | grep -q $key; then
  96             $GPG --quiet --batch --delete-key --yes ${key}
  97         fi
  98     done
  99 }
 100
 101
 102 usage() {
 103     echo "Usage: apt-key [command] [arguments]"
 104     echo
 105     echo "Manage apt's list of trusted keys"
 106     echo
 107     echo "  apt-key add <file>          - add the key contained in <file> ('-' for stdin)"
 108     echo "  apt-key del <keyid>         - remove the key <keyid>"
 109     echo "  apt-key export <keyid>      - output the key <keyid>"
 110     echo "  apt-key exportall           - output all trusted keys"
 111     echo "  apt-key update              - update keys using the keyring package"
 112     echo "  apt-key net-update          - update keys using the network"
 113     echo "  apt-key list                - list keys"
 114     echo
 115 }
 116
 117 command="$1"
 118 if [ -z "$command" ]; then
 119     usage
 120     exit 1
 121 fi
 122 shift
 123
 124 if [ "$command" != "help" ] && ! which gpg >/dev/null 2>&1; then
 125     echo >&2 "Warning: gnupg does not seem to be installed."
 126     echo >&2 "Warning: apt-key requires gnupg for most operations."
 127     echo >&2
 128 fi
 129
 130 case "$command" in
 131     add)
 132         $GPG --quiet --batch --import "$1"
 133         echo "OK"
 134         ;;
 135     del|rm|remove)
 136         $GPG --quiet --batch --delete-key --yes "$1"
 137         echo "OK"
 138         ;;
 139     update)
 140         update
 141         ;;
 142     net-update)
 143         net_update
 144         ;;
 145     list)
 146         $GPG --batch --list-keys
 147         ;;
 148     finger*)
 149         $GPG --batch --fingerprint
 150         ;;
 151     export)
 152         $GPG --armor --export "$1"
 153         ;;
 154     exportall)
 155         $GPG --armor --export
 156         ;;
 157     adv*)
 158         echo "Executing: $GPG $*"
 159         $GPG $*
 160         ;;
 161     help)
 162         usage
 163         ;;
 164     *)
 165         usage
 166         exit 1
 167         ;;
 168 esac