gnupg/tools/mail-signed-keys

#!/bin/sh

# FIXME: Add --dry-run,  use only valid email addreses, extract only given keys

dryrun=0
if [ "$1" = "--dry-run" ]; then
   dryrun=1
   shift
fi

if [ -z "$1" -o -z "$2" ]; then
   echo "usage: mail-signed-keys keyring signedby" >&2
   exit 1
fi

if [ ! -f $1 ]; then
    echo "mail-signed-keys: '$1': no such file" >&2
    exit 1
fi

[ -f '.#tdb.tmp' ] && rm '.#tdb.tmp'
ro="--homedir . --no-options --trustdb-name=./.#tdb.tmp --dry-run --lock-never --no-default-keyring --keyring $1"

signedby=`gpg $ro --fast-list-mode --list-keys --with-colons $2 \
	  2>/dev/null | awk -F: '$1=="pub" {print $5; exit 0}'`

if [ -z "$signedby" ]; then
    echo "mail-signed-keys: '$2': no such signator" >&2
    exit 1
fi

if [ "$dryrun" = "0" ]; then
  echo "About to send the the keys signed by $signedby" >&2
  echo -n "to their owners.  Do you really want to do this? (y/N)" >&2
  read
  [ "$REPLY" != "y" -a "$REPLY" != "Y" ] && exit 0
fi

gpg $ro --check-sigs --with-colons 2>/dev/null \
     | awk -F: -v signedby="$signedby" -v gpgopt="$ro" -v dryrun="$dryrun" '
BEGIN	      { sendmail="/usr/lib/sendmail -oi -t " }
$1 == "pub"   { nextkid=$5; nextuid=$10
		if( uidcount > 0 ) { myflush() }
		kid=nextkid; uid=nextuid; next
	      }
$1 == "uid"   { uid=$10 ; next }
$1 == "sig" && $2 == "!" && $5 == signedby  { uids[uidcount++] = uid; next }
END	      {  if( uidcount > 0 ) { myflush() } }

function myflush()
{
       if ( kid == signedby ) { uidcount=0; return }
       print "sending key " substr(kid,9) " to" | "cat >&2"
       for(i=0; i < uidcount; i++ ) {
	   print "    " uids[i] | "cat >&2"
           if( dryrun == 0 ) {
	      if( i == 0 ) {
		 printf "To: %s", uids[i]   | sendmail
	      }
	      else {
		 printf ",\n    %s", uids[i]   | sendmail
	      }
           }
       }
       if(dryrun == 0) {  
         printf "\n"                                        | sendmail
         print "Subject: I signed your key " substr(kid,9)  | sendmail
         print ""                                           | sendmail
         print "Hi,"                                        | sendmail
         print ""                                           | sendmail
         print "Here you get back the signed key."          | sendmail
         print ""                                           | sendmail
         print "ciao,"                                      | sendmail
         print "     your Key Signator"                     | sendmail
         print ""                                           | sendmail
         cmd = "gpg " gpgopt " --export -a " kid " 2>/dev/null"
         while( (cmd | getline) > 0 ) {
             print | sendmail
         }
         print ""                                           | sendmail
         close(cmd)
         close( sendmail )
       }
       uidcount=0
}
'