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