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