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