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Added code to package up the certificate and mail it to a certificate manager.
Remaining work:
- Add Cleanup
- Add Pod documentation.
- Change debug value to 0 to make this less verbose.

    1: #!/usr/bin/perl
    2: # The LearningOnline Network
    3: # CrGenerate - Generate a loncapa certificate request.
    4: #
    5: # $Id: CrGenerate.pl,v 1.5 2004/07/01 10:58:29 foxr Exp $
    6: #
    7: # Copyright Michigan State University Board of Trustees
    8: #
    9: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
   10: #
   11: # LON-CAPA is free software; you can redistribute it and/or modify
   12: # it under the terms of the GNU General Public License as published by
   13: # the Free Software Foundation; either version 2 of the License, or 
   14: # (at your option) any later version.
   15: #
   16: # LON-CAPA is distributed in the hope that it will be useful,
   17: # but WITHOUT ANY WARRANTY; without even the implied warranty of
   18: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   19: # GNU General Public License for more details.
   20: #
   21: # You should have received a copy of the GNU General Public License
   22: # along with LON-CAPA; if not, write to the Free Software
   23: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   24: #
   25: # /home/httpd/html/adm/gpl.txt
   26: #
   27: 
   28: 
   29: # http://www.lon-capa.org/
   30: #
   31: #
   32: #  This script:
   33: #  1. Generates a private host key and certificate request/
   34: #  2. Decodes the private host key
   35: #  3. Installs the private host key with appropriate permissions
   36: #     in the  appropriate directory (sorry to be vague about this, but
   37: #     the installation directory is determined by external configuration
   38: #     info).
   39: # 4. Constructs an email to the loncapa cluster administrator
   40: #    consisting of a generic heading and the certificate request as a MIME
   41: #    attachment.
   42: # 5. Sends the email and
   43: # 6. Cleans up after itself by removing any temp files generated.
   44: #
   45: #
   46: 
   47: 
   48: # Import section:
   49: 
   50: use strict;
   51: use MIME::Entity;
   52: use LONCAPA::Configuration;
   53: use File::Copy;
   54: 
   55: #  Global variable declarations:4
   56: 
   57: my $SSLCommand;			  # Full path to openssl command.
   58: my $CertificateDirectory;	  # LONCAPA Certificate directory.
   59: my $KeyFilename;	          # Key filename (within CertificateDirectory).
   60: my $RequestEmail;		  # Email address of loncapa cert admin.
   61: my $WebUID;			# UID of web user.
   62: my $WebGID;			# GID of web user.
   63: 
   64: my $Passphrase="loncapawhatever";      # Initial passphrase for keyfile
   65: my $RequestFile="loncapaRequest.pem";  # Name of Certificate request file.
   66: my $EncodedKey="hostkey.pem";	       # Name of encoded key file.
   67: 
   68: my $WebUser="www";		# Username running the web server.
   69: my $WebGroup="www";		# Group name running the web server.
   70: 
   71: #   Debug/log support:
   72: #
   73: my $DEBUG = 1;			# 1 for on, 0 for off.
   74: 
   75: # Send debugging to stderr.
   76: # Parameters:
   77: #     msg   - Message to send to stderr.
   78: # Implicit Inputs:
   79: #    $DEBUG - message is only written if this is true.
   80: #
   81: sub Debug {
   82:     my $msg  = shift;
   83:     if($DEBUG) {
   84: 	print STDERR "$msg\n";
   85:     }
   86: }
   87: 
   88: #
   89: #  Decodes the email address from a textual certificate request
   90: #  file:
   91: # Parameters:
   92: #    $RequestFile   - Name of the file containing the textual
   93: #                     version of the certificate request.
   94: # Returns:
   95: #   Email address contained in the request.
   96: # Failure:
   97: #   If unable to open or unable to fine an email address in the file,
   98: #   dies with a message.
   99: #
  100: sub DecodeEmailFromRequest {
  101:     Debug("DecodeEmailFromRequest");
  102: 
  103:     my $RequestFile = shift;
  104:     Debug("Request file is called $RequestFile");
  105: 
  106:     # We need to look for the line that has a "/Email=" in it.
  107: 
  108:     Debug("opening $RequestFile");
  109:     open REQUEST, "< $RequestFile" or
  110: 	die "Unable to open $RequestFile to parse return email address";
  111: 
  112:     Debug("Parsing request file");
  113:     my $line;
  114:     my $found = 0;
  115:     while($line = <REQUEST>) {
  116: 	chomp($line);		# Never a bad idea.
  117: 	if($line =~ /\/Email=/) {
  118: 	    $found = 1;
  119: 	    last;
  120: 	}
  121:     }
  122:     if(!$found) {
  123: 	die "There does not appear to be an email address in $RequestFile";
  124:     }
  125: 
  126:     close REQUEST;
  127: 
  128:     Debug("Found /Email in $line");
  129:     
  130:     # $line contains a bunch of comma separated key=value pairs.
  131:     # The problem is that after these is a /Email=<what-we-want>
  132:     # first we'll split the line up at the commas.
  133:     # Then we'll look for the entity with the /Email in it.
  134:     # That line will get split at the / and then the Email=<what-we-want>
  135:     # gets split at the =.  I'm sure there's some clever regular expression
  136:     # substitution that will get it all in a single line, but I think 
  137:     # this approach is gonna be much easier to understand than punctuation
  138:     # sneezed all over the page:
  139:    
  140:     my @commalist = split(/,/, $line);
  141:     my $item;
  142:     my $emailequals = "";
  143:     foreach $item  (@commalist) {
  144: 	if($item =~ /\/Email=/) { # gotcha...
  145: 	    $emailequals = $item;
  146: 	    last;
  147: 	}
  148:     }
  149: 
  150:     Debug("Pulled out $emailequals from $line");
  151:     my ($trash, $addressequals) = split(/\//, $emailequals);
  152:     Debug("Futher pulled out $addressequals");
  153: 
  154:     my ($junk, $address) = split(/=/, $addressequals);
  155:     Debug("Parsed final email addresss as $address");
  156:     
  157: 
  158: 
  159:     return $address;
  160: }
  161: 
  162: #
  163: #   Read the LonCAPA web config files to get the values of the 
  164: #   configuration global variables we need:
  165: # Implicit inputs:
  166: #   loncapa.conf   - configuration file to read (user specific).
  167: # Implicit outputs (see global variables section):
  168: #   SSLCommand,
  169: #   CertificateDirectory
  170: #   KeyfileName
  171: #   RequestEmail
  172: # Side-Effects:
  173: #   Exit with error if cannot complete.
  174: #
  175: sub ReadConfig {
  176: 
  177:     Debug("Reading configuration");
  178:     my $perlvarref = LONCAPA::Configuration::read_conf('loncapa.conf');
  179:     
  180:     # Name of the SSL Program
  181: 
  182:     if($perlvarref->{SSLProgram}) {
  183: 	$SSLCommand = $perlvarref->{SSLProgram};
  184: 	Debug("SSL Command: $SSLCommand");
  185:     }
  186:     else {
  187: 	die "Unable to read the SSLCommand configuration option\n";
  188:     }
  189: 
  190:     # Where the certificates, and host key are installed:
  191: 
  192:     if($perlvarref->{lonCertificateDirectory}) {
  193: 	$CertificateDirectory = $perlvarref->{lonCertificateDirectory};
  194: 	Debug("Local certificate Directory: $CertificateDirectory");
  195:     }
  196:     else {
  197: 	die "Unable to read SSLDirectory configuration option\n";
  198:     }
  199:     # The name of the host key file (to be installed in SSLDirectory).
  200:     #
  201:     if($perlvarref->{lonnetPrivateKey}) {
  202: 	$KeyFilename  = $perlvarref->{lonnetPrivateKey};
  203: 	Debug("Private key will be installed as $KeyFilename");
  204:     } 
  205:     else {
  206: 	die "Unable to read lonnetPrivateKey conrig paraemter\n";
  207:     }
  208:     #  The email address to which the certificate request is sent:
  209: 
  210:     if($perlvarref->{SSLEmail}) {
  211: 	$RequestEmail = $perlvarref->{SSLEmail};
  212: 	Debug("Certificate request will be sent to $RequestEmail");
  213:     }
  214:     else {
  215: 	die "Could not read SSLEmail coniguration key";
  216:     }
  217:     #  The UID/GID of the web user: It's possible the web user's
  218:     #  GID is not its primary, so we'll translate that form the
  219:     #  group file separately.
  220: 
  221:     my ($login, $pass, $uid, $gid) = getpwnam($WebUser);
  222:     if($uid) {
  223: 	$WebUID = $uid;
  224: 	Debug("Web user: $WebUser -> UID: $WebUID");
  225:     }
  226:     else {
  227: 	die "Could not translate web user: $WebUser to a uid.";
  228:     }
  229:     my $gid = getgrnam($WebGroup);
  230:     if($gid) {
  231: 	$WebGID = $gid;
  232: 	Debug("Web group: $WebGroup -> GID $WebGID");
  233:     }
  234:     else {
  235: 	die "Unable to translate web group $WebGroup to a gid.";
  236:     }
  237: }
  238: #
  239: #   Generate a certificate request.
  240: #   The openssl command is issued to create a local host key and
  241: #   a certificate request.  The key is initially encoded.
  242: #   We will eventually decode this, however, since the key
  243: #   passphrase is open source we'll protect even the initial 
  244: #   encoded key file too.  We'll need to decode the keyfile since
  245: #   otherwise, openssl will need a passphrase everytime an ssl connection
  246: #   is created (ouch).
  247: # Implicit Inputs:
  248: #    Passphrase   - Initial passphrase for the encoded key.
  249: #    RequestFile  - Filename of the certificate request.
  250: #    EncodedKey   - Filename of the encoded key file.
  251: #
  252: # Side-Effects:
  253: #
  254: sub GenerateRequest {
  255:     Debug("Generating the request and key");
  256: 
  257:     print "We are now going to generate the certificate request\n";
  258:     print "You will be prompted by openssl for several pieces of \n";
  259:     print "information.  Most of this information is for documentation\n";
  260:     print "purposes only, so it's not critical if you make a mistake.\n";
  261:     print "However:  The generated certificate will be sent to the \n";
  262:     print "Email address you provide, and you should leave the optional\n";
  263:     print "Challenge password blank.\n";
  264: 
  265:     my $requestcmd = $SSLCommand." req -newkey rsa:1024 "
  266:                                 ." -keyout hostkey.pem "
  267:                                 ." -keyform PEM "
  268:                                 ." -out request.pem "
  269:                                 ." -outform PEM "
  270:                                 ." -passout pass:$Passphrase";
  271:     my $status = system($requestcmd);
  272:     if($status) {
  273: 	die "Certificate request generation failed: $status";
  274:     }
  275: 
  276:     chmod(0600, "hostkey.pem");	# Protect key since passphrase is opensrc.
  277: 
  278:     Debug("Decoding the key");
  279:     my $decodecmd = $SSLCommand." rsa -in  hostkey.pem"
  280:                                ."     -out hostkey.dec"
  281:                                ."     -passin pass:$Passphrase";
  282:     $status = system($decodecmd);
  283:     if($status) {
  284: 	die "Host key decode failed";
  285:     }
  286: 
  287:     chmod(0600, "hostkey.dec");	# Protect the decoded hostkey.
  288: 
  289:     #  Create the textual version of the request too:
  290: 
  291:     Debug("Creating textual version of the request for users.");
  292:     my $textcmd = $SSLCommand." req -in request.pem -text "
  293: 	                     ." -out request.txt";
  294:     $status = system($textcmd);
  295:     if($status) {
  296: 	die "Textualization of the certificate request failed";
  297:     }
  298: 	                     
  299: 
  300:     Debug("Done");
  301: }
  302: #
  303: #  Installs the decoded host key (hostkey.dec) in the 
  304: #  certificate directory with the correct permissions.
  305: #
  306: # Implicit Inputs:
  307: #    hostkey.dec           - the name of the host key file.
  308: #    $CertificateDirectory - where the key file gets installed
  309: #    $KeyFilename          - Final name of the key file.
  310: #    $WebUser              - User who should own the key file.
  311: #    $WebGroup             - Group who should own the key file.
  312: #    0400                  - Permissions to give to the installed key
  313: #                            file.
  314: #    0700                  - Permissions given to the certificate
  315: #                            directory if created.
  316: # Side-Effects:
  317: #    If necessary, $CertificateDirectory is created.
  318: #    $CertificateDirectory/$KeyFilename is ovewritten with the
  319: #          contents of hostkey.dec in the cwd.
  320: #
  321: sub InstallKey {
  322:     Debug("InstallKey");
  323: 
  324:     Debug("Need to create certificate directory?");
  325:     if(!(-d $CertificateDirectory)) {
  326: 	
  327: 	Debug("Creating");
  328: 	mkdir($CertificateDirectory, 0700);
  329: 	chown($WebUID, $WebGID, $CertificateDirectory);
  330:     }
  331:     else {
  332: 	Debug("Exists");
  333:     }
  334: 
  335:     Debug("Installing the key file:");
  336:     my $FullKeyPath = $CertificateDirectory."/".$KeyFilename;
  337:     copy("hostkey.dec", $FullKeyPath);
  338: 
  339:     Debug("Setting ownership and permissions");
  340:     chmod(0400, $FullKeyPath);
  341:     chown($WebUID, $WebGID, $FullKeyPath);
  342: 
  343:     Debug("Done");
  344: }
  345: #
  346: #  Package up a certificate request and email it to the loncapa
  347: #  admin.  The email sent:
  348: #   - Has the subject: "LonCAPA certificate request for hostname
  349: #   - Has, as the body, the text version of the certificate.
  350: #     This can be inspected by the human issuing the certificate
  351: #     to decide if they want to really grant it... it will
  352: #     have the return email and all the documentation fields.
  353: #   - Has a text attachment that consists of the .pem version of the
  354: #     request.  This is extracted by the human granting the 
  355: #     certificate and used as input to the CrGrant.pl script.
  356: #
  357: #
  358: # Implicit inputs:
  359: #    request.pem    - The certificate request file.
  360: #    request.txt    - Textual version of the request file.
  361: #    $RequestEmail  - Email address to which the key is sent.
  362: #  
  363: sub MailRequest {
  364:     Debug("Mailing request");
  365: 
  366:     # First we need to pull out the return address from the textual
  367:     # form of the certificate request:
  368: 
  369:     my $FromEmail = DecodeEmailFromRequest("request.txt");
  370:     if(!$FromEmail) {
  371: 	die "From email address cannot be decoded from certificate request";
  372:     }
  373:     Debug("Certificate will be sent back to $FromEmail");
  374: 
  375:     # Create the email message headers and all:
  376:     #
  377:     Debug("Creating top...level...");
  378:     my $top = MIME::Entity->build(Type     => "multipart/mixed",
  379: 				  From     => $FromEmail,
  380: 				  To       => $RequestEmail,
  381: 				  Subject  => "LonCAPA certificate request");
  382:     if(!$top) {
  383: 	die "Unable to create top level mime document";
  384:     }
  385:     Debug("Attaching Text formatted certificate request");
  386:     $top->attach(Path     => "request.txt");
  387: 
  388: 
  389:     Debug("Attaching PEM formatted certificate request...");
  390:     $top->attach(Type       => "text/plain",
  391: 		 Path      => "request.pem");
  392: 
  393:     #  Now send the email via sendmail this should work as long as
  394:     #  sendmail or postfix are configured properly.  Most other mailers
  395:     #  define the sendmail command too for compatibility with what
  396:     #  we're trying to do.  I decided to use sendmail directly because
  397:     #  otherwise I'm not sure the mail headers I created in $top
  398:     #  will get properly passed as headers to other mailer thingies.
  399:     #
  400: 
  401:     Debug("Mailing..");
  402: 
  403:     open MAILPIPE, "| /usr/lib/sendmail -t -oi -oem" or 
  404: 	die "Failed to open pipe to sendmail: $!";
  405:     $top->print(\*MAILPIPE);
  406:     close MAILPIPE;
  407: 
  408: 
  409: 
  410:     Debug("Done");
  411: } 
  412: sub Cleanup {}
  413: 
  414: 
  415: 
  416: #  Entry point:
  417: 
  418: Debug("Starting program");
  419: ReadConfig;			# Read loncapa apache config file.
  420: GenerateRequest;		# Generate certificate request.
  421: InstallKey;			# Install the user's key.
  422: MailRequest;			# Mail certificate request to loncapa 
  423: Cleanup;			# Cleanup temp files created.
  424: 
  425: Debug("Done");