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