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Diff for /loncom/lonlocal.pm between versions 1.2 and 1.6

version 1.2, 2004/05/28 09:39:11 version 1.6, 2004/06/17 10:15:46
Line 41  use strict; Line 41  use strict;
   
 # CPAN/standard modules  # CPAN/standard modules
   
 use English;  
 use Crypt::IDEA;  use Crypt::IDEA;
   use Fcntl;
   
 # LONCAPA modules  # LONCAPA modules
   
Line 51  use LONCAPA::Configuration; Line 51  use LONCAPA::Configuration;
 # Global variables:  # Global variables:
   
 my $perlvar; # Refers to the apache perlsetvar hash.  my $perlvar; # Refers to the apache perlsetvar hash.
   my $pathsep   = "/"; # Unix path seperator 
   my $fileindex = 0; # Per process lonc uniquifier.
   my $lastError; # Reason for last failure.
   
   
   #  Debugging:
   
   my $DEBUG = 0;
   
   sub Debug {
       my $msg = shift;
       print STDERR "$msg\n";
   }
   
 # Initialization  # Initialization
   
Line 59  $perlvar = LONCAPA::Configuration::read_ Line 72  $perlvar = LONCAPA::Configuration::read_
   
 #------------------------------------------------------------------------  #------------------------------------------------------------------------
 #  #
 # Name          BuildKey  # Name          CreateCipherKey
 # Description:  Create an encryption key.  # Description:  Create an encryption key.
 # Returns:      The key.  # Returns:      The key.
 #  #
Line 69  sub CreateCipherKey { Line 82  sub CreateCipherKey {
     my $binaryKey;      my $binaryKey;
     my $cipherkey;      my $cipherkey;
           
     # we'll use the output of /dev/random to produce our key.      # we'll use the output of /dev/urandom to produce our key.
     # On a system with decent entropy, this ought to be much more      # On a system with decent entropy, this ought to be much more
     # random than all the playing that used to be done to get a key.      # random than all the playing that used to be done to get a key.
     #      # On a system with not so decent entropy we'll still get an ok key.
       # My concern with /dev/random is that we may block for an indefinite
       # time period...where for us decent keys are probably good enough.
           
     $keylength   =  IDEA::keysize();      $keylength   =  IDEA::keysize();
     open(RANDOM, "</dev/random");      open(RANDOM, "</dev/urandom");
     sysread(RANDOM, $binaryKey, $keylength);      sysread(RANDOM, $binaryKey, $keylength);
     close RANDOM;      close RANDOM;
           
Line 98  sub CreateCipherKey { Line 113  sub CreateCipherKey {
 #     A two element list containing:  #     A two element list containing:
 #     - The private key that was  created  #     - The private key that was  created
 #     - The full path to the file that contains it.  #     - The full path to the file that contains it.
 #  #     or undef on failure.
 sub CreateKeyFile {  sub CreateKeyFile {
   
     # To create the file we need some perlvars to tell us where the      # To create the file we need some perlvars to tell us where the
     # certificate directory. We'll make a file named localkey.$pid      # certificate directory. We'll make a file named localkey.$pid
     # there, and set the mode before writing into it.      # there, and set the mode before writing into it.
     #      #
           $fileindex++;
       my $CertificateDir = $perlvar->{lonCertificateDirectory};
       my $Filename       = $CertificateDir.$pathsep.".$fileindex.".$$;
   
       # If this file already exists, this is a recoverable error... we just
       # delete the earlier incarnation of the file.
   
       if (-w $Filename) {
    unlink $Filename;
       }
   
       # If the file still exists this is really really bad:
       # It most likely means someone has been devious enough to drop a key file
       # in place to attemp to spoof the lond.  We'll fail in that case hoping
       # that the user looks at the log to figure out that local connections
       # are failing.
       
       if( -e $Filename) {
    $lastError = "Key file already exists after deletion probably a spoof!";
    return undef;
       }
       #  Now we can create the file  we use sysopen in order to ensure
       # the file is created with the appropriate locked down permissions.
   
       if(! sysopen(KEYFILE, $Filename, O_CREAT | O_EXCL | O_WRONLY, 0600)) {
    $lastError = "Creation of key file failed ".$!;
    return undef;
       }
       # Create the key, write it to the file and close the file:
   
       my $key = CreateCipherKey();
       print KEYFILE "$key\n";
       close KEYFILE;
   
       return ($key, $Filename);
   
           
 }  }
   
   
   # Name   ReadKeyFile
   # Description Opens the private local key file and reads the IDEA key from it.
   # Parameters
   #       Name          Type       Description
   #               Filename  string       path to key file
   #
   # NOTE:
   #   Reading the keyfile is a one-time thing.  This sub destroys the
   #   keyfile after reading it to ensure the one-timedness of the keys they
   #   contain!!
   # Returns
   #    On success the IDEA key that was written into the key fileon failure undef.
   #
   #
   sub ReadKeyFile {
       my $Filename = shift;
       Debug("ReadKeyFile: $Filename");
   
   
       if(! open(KEYFILE, "<$Filename")) {
    Debug(" Open of $Filename failed\n");
    $lastError = "Key file open failed";
    return undef
       }
       my $key = <KEYFILE>;
       chomp($key);
       Debug(" Read key: $key");
       close KEYFILE;
       unlink $Filename;
       #
       #  If the filename still exists some spoofer wrote it with the wrong
       #  permissions:
       #
       if(-e $Filename) {
    Debug("File did not get deleted");
    $lastError = "Key file still exists after unlink";
    return undef;
       }
       #
       #  The IDEA key must be  IDEA::keysize*2 characters
       #  long.   If it  isn't probably someone's trying to break us by
       #  hitting the timing hole between the file write and read...
       #  replacing our file... of course if they read this comment they'll
       #  be too smart to put an incorrectly sized file
       #
       my $keylen = length($key);
       my $rightlen= IDEA::keysize()*2;
       if($keylen != $rightlen) {
    Debug("Key is incorrect length is $keylen sb $rightlen");
    $lastError = "Key file has incorrect length";
    return undef;
       }
       Debug("Returning key: $key to caller");
       return $key;   
   }
Removed from v.1.2  
changed lines
  Added in v.1.6

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