--- loncom/Lond.pm	2022/02/20 21:06:30	1.8.2.3.2.3
+++ loncom/Lond.pm	2023/06/20 13:27:42	1.24
@@ -1,6 +1,6 @@
 # The LearningOnline Network
 #
-# $Id: Lond.pm,v 1.8.2.3.2.3 2022/02/20 21:06:30 raeburn Exp $
+# $Id: Lond.pm,v 1.24 2023/06/20 13:27:42 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -37,8 +37,14 @@ use lib '/home/httpd/lib/perl/';
 use LONCAPA;
 use Apache::lonnet;
 use GDBM_File;
+use MIME::Base64;
+use Crypt::OpenSSL::X509;
+use Crypt::X509::CRL;
+use Crypt::PKCS10;
 use Net::OAuth;
 use Crypt::CBC;
+use Digest::SHA;
+use Digest::MD5 qw(md5_hex);
 
 sub dump_with_regexp {
     my ( $tail, $clientversion ) = @_;
@@ -812,9 +818,219 @@ sub is_course {
     return $iscourse;
 }
 
+sub server_certs {
+    my ($perlvar,$lonhost,$hostname) = @_;
+    my %pemfiles = (
+                     key      => 'lonnetPrivateKey',
+                     host     => 'lonnetCertificate',
+                     hostname => 'lonnetHostnameCertificate',
+                     ca       => 'lonnetCertificateAuthority',
+                     crl      => 'lonnetCertRevocationList',
+                   );
+    my (%md5hash,%expected_cn,%expired,%revoked,%wrongcn,%info,$crlfile,$cafile,
+        %rvkcerts,$numrvk);
+    %info = (
+                key => {},
+                ca  => {},
+                host => {},
+                hostname => {},
+                crl => {},
+            );
+    my @ordered = ('crl','key','ca','host','hostname');
+    if (ref($perlvar) eq 'HASH') {
+        $expected_cn{'host'} = $Apache::lonnet::serverhomeIDs{$hostname};
+        $expected_cn{'hostname'} = 'internal-'.$hostname;
+        my $certsdir = $perlvar->{'lonCertificateDirectory'};
+        if (-d $certsdir) {
+            $crlfile = $certsdir.'/'.$perlvar->{$pemfiles{'crl'}};
+            $cafile = $certsdir.'/'.$perlvar->{$pemfiles{'ca'}};
+            foreach my $key (@ordered) {
+                if ($perlvar->{$pemfiles{$key}}) {
+                    my $file = $certsdir.'/'.$perlvar->{$pemfiles{$key}};
+                    if (-e $file) {
+                        if ($key eq 'crl') {
+                             if ((-e $crlfile) && (-e $cafile)) {
+                                 if (open(PIPE,"openssl crl -in $crlfile -inform pem -CAfile $cafile -noout 2>&1 |")) {
+                                     my $crlstatus = <PIPE>;
+                                     close(PIPE);
+                                     chomp($crlstatus);
+                                     if ($crlstatus =~ /OK/) {
+                                         $info{$key}{'status'} = 'ok';
+                                         $info{$key}{'details'} = 'CRL valid for CA';
+                                     }
+                                 }
+                             }
+                             if (open(my $fh,'<',$crlfile)) {
+                                 my $pem_crl = '';
+                                 while (my $line=<$fh>) {
+                                     chomp($line);
+                                     next if ($line eq '-----BEGIN X509 CRL-----');
+                                     next if ($line eq '-----END X509 CRL-----');
+                                     $pem_crl .= $line;
+                                 }
+                                 close($fh);
+                                 my $der_crl = MIME::Base64::decode_base64($pem_crl);
+                                 if ($der_crl ne '') {
+                                     my $decoded = Crypt::X509::CRL->new( crl => $der_crl );
+                                     if ($decoded->error) {
+                                         $info{$key}{'status'} = 'error';
+                                     } elsif (ref($decoded)) {
+                                         $info{$key}{'start'} = $decoded->this_update;
+                                         $info{$key}{'end'} = $decoded->next_update;
+                                         $info{$key}{'alg'} = $decoded->SigEncAlg.' '.$decoded->SigHashAlg;
+                                         $info{$key}{'cn'} = $decoded->issuer_cn;
+                                         $info{$key}{'email'} = $decoded->issuer_email;
+                                         $info{$key}{'size'} = $decoded->signature_length;
+                                         my $rlref = $decoded->revocation_list;
+                                         if (ref($rlref) eq 'HASH') {
+                                             foreach my $key (keys(%{$rlref})) {
+                                                 my $hkey = sprintf("%X",$key);
+                                                 $rvkcerts{$hkey} = 1;
+                                             }
+                                             $numrvk = scalar(keys(%{$rlref}));
+                                             if ($numrvk) {
+                                                 $info{$key}{'details'} .= " ($numrvk revoked)"; 
+                                             }
+                                         }
+                                     }
+                                 }
+                            }
+                        } elsif ($key eq 'key') {
+                            if (open(PIPE,"openssl rsa -noout -in $file -check |")) {
+                                my $check = <PIPE>;
+                                close(PIPE);
+                                chomp($check);
+                                $info{$key}{'status'} = $check;
+                            }
+                            if (open(PIPE,"openssl rsa -noout -modulus -in $file | openssl md5 |")) {
+                                $md5hash{$key} = <PIPE>;
+                                close(PIPE);
+                                chomp($md5hash{$key});
+                            }
+                        } else {
+                            if ($key eq 'ca') {
+                                if (open(PIPE,"openssl verify -CAfile $file $file |")) {
+                                    my $check = <PIPE>;
+                                    close(PIPE);
+                                    chomp($check);
+                                    if ($check eq "$file: OK") {
+                                        $info{$key}{'status'} = 'ok';
+                                    } else {
+                                        $check =~ s/^\Q$file\E\:?\s*//;
+                                        $info{$key}{'status'} = $check;
+                                    }
+                                }
+                            } else {
+                                if (open(PIPE,"openssl x509 -noout -modulus -in $file | openssl md5 |")) {
+                                    $md5hash{$key} = <PIPE>;
+                                    close(PIPE);
+                                    chomp($md5hash{$key});
+                                }
+                            }
+                            my $x509 = Crypt::OpenSSL::X509->new_from_file($file);
+                            my @items = split(/,\s+/,$x509->subject());
+                            foreach my $item (@items) {
+                                my ($name,$value) = split(/=/,$item);
+                                if ($name eq 'CN') {
+                                    $info{$key}{'cn'} = $value;
+                                }
+                            }
+                            $info{$key}{'start'} = $x509->notBefore();
+                            $info{$key}{'end'} = $x509->notAfter();
+                            $info{$key}{'alg'} = $x509->sig_alg_name();
+                            $info{$key}{'size'} = $x509->bit_length();
+                            $info{$key}{'email'} = $x509->email();
+                            $info{$key}{'serial'} = uc($x509->serial());
+                            $info{$key}{'issuerhash'} = $x509->issuer_hash();
+                            if ($x509->checkend(0)) {
+                                $expired{$key} = 1;
+                            }
+                            if (($key eq 'host') || ($key eq 'hostname')) {
+                                if ($info{$key}{'cn'} ne $expected_cn{$key}) {
+                                    $wrongcn{$key} = 1;
+                                }
+                                if (($numrvk) && ($info{$key}{'serial'})) {
+                                    if ($rvkcerts{$info{$key}{'serial'}}) {
+                                        $revoked{$key} = 1;
+                                    }
+                                }
+                            }
+                        }
+                    }
+                    if (($key eq 'host') || ($key eq 'hostname')) {
+                        my $csrfile = $file;
+                        $csrfile =~ s/\.pem$/.csr/;
+                        if (-e $csrfile) {
+                            if (open(PIPE,"openssl req -noout -modulus -in $csrfile |openssl md5 |")) {
+                                my $csrhash = <PIPE>;
+                                close(PIPE);
+                                chomp($csrhash);
+                                if ((!-e $file) || ($csrhash ne $md5hash{$key}) || ($expired{$key}) ||
+                                    ($wrongcn{$key}) || ($revoked{$key})) {
+                                    Crypt::PKCS10->setAPIversion(1);
+                                    my $decoded = Crypt::PKCS10->new( $csrfile,(PEMonly => 1, readFile => 1));
+                                    if (ref($decoded)) {
+                                        if ($decoded->commonName() eq $expected_cn{$key}) {
+                                            $info{$key.'-csr'}{'cn'} = $decoded->commonName();
+                                            $info{$key.'-csr'}{'alg'} = $decoded->pkAlgorithm();
+                                            $info{$key.'-csr'}{'email'} = $decoded->emailAddress();
+                                            my $params = $decoded->subjectPublicKeyParams();
+                                            if (ref($params) eq 'HASH') {
+                                                $info{$key.'-csr'}{'size'} = $params->{keylen};
+                                            }
+                                            $md5hash{$key.'-csr'} = $csrhash;
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+    foreach my $key ('host','hostname') {
+        if ($md5hash{$key}) {
+            if ($md5hash{$key} eq $md5hash{'key'}) {
+                if ($revoked{$key}) {
+                    $info{$key}{'status'} = 'revoked';
+                } elsif ($expired{$key}) {
+                    $info{$key}{'status'} = 'expired';
+                } elsif ($wrongcn{$key}) {
+                    $info{$key}{'status'} = 'wrongcn';
+                } elsif ((exists($info{'ca'}{'issuerhash'})) &&
+                         ($info{'ca'}{'issuerhash'} ne $info{$key}{'issuerhash'})) {
+                    $info{$key}{'status'} = 'mismatch';
+                } else {
+                    $info{$key}{'status'} = 'ok';
+                }
+            } elsif ($info{'key'}{'status'} =~ /ok/) {
+                $info{$key}{'status'} = 'otherkey';
+            } else {
+                $info{$key}{'status'} = 'nokey';
+            }
+        }
+        if ($md5hash{$key.'-csr'}) {
+            if ($md5hash{$key.'-csr'} eq $md5hash{'key'}) {
+                $info{$key.'-csr'}{'status'} = 'ok';
+            } elsif ($info{'key'}{'status'} =~ /ok/) {
+                $info{$key.'-csr'}{'status'} = 'otherkey';
+            } else {
+                $info{$key.'-csr'}{'status'} = 'nokey';
+            }
+        }
+    }
+    my $result;
+    foreach my $key (keys(%info)) {
+        $result .= &escape($key).'='.&Apache::lonnet::freeze_escape($info{$key}).'&';
+    }
+    $result =~ s/\&$//;
+    return $result;
+}
+
 sub get_dom {
     my ($userinput) = @_;
-    my ($cmd,$udom,$namespace,$what) =split(/:/,$userinput,4);
+    my ($cmd,$udom,$namespace,$what) =split(/:/,$userinput,4); 
     my $hashref = &tie_domain_hash($udom,$namespace,&GDBM_READER()) or
         return "error: ".($!+0)." tie(GDBM) Failed while attempting $cmd";
     my $qresult='';
@@ -980,6 +1196,9 @@ sub domlti_itemid {
         $name = $context;
     } else {
         $name = 'lti';
+        if ($context eq '') {
+            $context = 'provider';
+        }
     }
     $cachename = $name.'enc';
     my %ltienc;
@@ -1040,6 +1259,182 @@ sub domlti_itemid {
     return $itemid;
 }
 
+sub sign_lti_payload {
+    my ($cdom,$cnum,$crsdef,$type,$context,$url,$idx,$keynum,$loncaparev,$paramsref,$inforef) = @_;
+    return unless (ref($paramsref) eq 'HASH');
+    my ($sigmethod,$callback,$reqtype,$reqmethod,$respfmt,$bodyhash);
+    if (ref($inforef) eq 'HASH') {
+        if (exists($inforef->{'method'})) {
+            $sigmethod = $inforef->{'method'};
+        }
+        if (exists($inforef->{'cb'})) {
+            $callback = $inforef->{'cb'};
+        }
+        if (exists($inforef->{'reqtype'})) {
+            $reqtype = $inforef->{'reqtype'};
+        }
+        if (exists($inforef->{'reqmethod'})) {
+            $reqmethod = $inforef->{'reqmethod'};
+        }
+        if (exists($inforef->{'body_hash'})) {
+            $bodyhash = $inforef->{'body_hash'};
+        }
+        if (exists($inforef->{'respfmt'})) {
+            $respfmt = $inforef->{'respfmt'};
+        }
+    }
+    my ($key,$secret) = &get_lti_credentials($cdom,$cnum,$crsdef,$type,$idx,$keynum,$loncaparev);
+    return if (($key eq '') || ($secret eq ''));
+    if ($sigmethod eq '') {
+        $sigmethod = 'HMAC-SHA1';
+    }
+    if ($callback eq '') {
+        $callback = 'about:blank',
+    }
+    if ($reqtype eq '') {
+        $reqtype = 'request token';
+    }
+    if ($reqmethod eq '') {
+        $reqmethod = 'POST';
+    }
+    srand( time() ^ ($$ + ($$ << 15))  ); # Seed rand.
+    my $nonce = Digest::SHA::sha1_hex(sprintf("%06x%06x",rand(0xfffff0),rand(0xfffff0)));
+    my $request;
+    if (($context eq 'grade') && ($reqtype eq 'consumer') && ($bodyhash ne '')) { 
+        $request = Net::OAuth->request($reqtype)->new(
+                           consumer_key => $key,
+                           consumer_secret => $secret,
+                           request_url => $url,
+                           request_method => $reqmethod,
+                           signature_method => $sigmethod,
+                           timestamp => time(),
+                           nonce => $nonce,
+                           body_hash => $bodyhash,
+        );
+        $request->add_required_message_params('body_hash');
+    } else {
+        $request = Net::OAuth->request($reqtype)->new(
+            consumer_key => $key,
+            consumer_secret => $secret,
+            request_url => $url,
+            request_method => 'POST',
+            signature_method => $sigmethod,
+            timestamp => time,
+            nonce => $nonce,
+            callback => $callback,
+            extra_params => $paramsref,
+            version      => '1.0',
+            );
+    }
+    $request->sign();
+    if ($respfmt eq 'to_post_body') {
+        return $request->to_post_body();
+    } elsif ($respfmt eq 'to_authorization_header') {
+        return $request->to_authorization_header();
+    } else {
+        return $request->to_hash();
+    }
+}
+
+sub get_lti_credentials {
+    my ($cdom,$cnum,$crsdef,$type,$idx,$keynum,$loncaparev) = @_;
+    my ($dbname,$name,$cachename,$hashid,$key,$secret,%ltienc);
+    if ($crsdef) {
+        $hashid = $cdom.'_'.$cnum;
+    } else {
+        $hashid = $cdom;
+    }
+    if ($type eq 'tools') {
+        if ($crsdef) {
+            $dbname = 'nohist_toolsenc';
+            $cachename = 'crsltitoolsenc';
+        } else {
+            $name = 'ltitools';
+            $dbname = 'encconfig';
+            $cachename = 'ltitoolsenc';
+        }
+    } elsif ($type eq 'linkprot') {
+        if ($crsdef) {
+            $dbname = 'nohist_ltienc';
+            $cachename = 'courseltienc';
+        } else {
+            $name = 'linkprot';
+            $dbname = 'encconfig';
+            $cachename = 'linkprotenc';
+        }
+    } elsif ($type eq 'lti') {
+        $name = 'lti';
+        $dbname = 'encconfig';
+        $cachename = 'ltienc';
+    }
+    my ($encresult,$enccached)=&Apache::lonnet::is_cached_new($cachename,$hashid);
+    if (defined($enccached)) {
+        if (ref($encresult) eq 'HASH') {
+            %ltienc = %{$encresult};
+        }
+    } else {
+        if ($crsdef) {
+            my $reply = &dump_with_regexp(join(":",($cdom,$cnum,$dbname,'','')),$loncaparev);
+            %ltienc = %{&Apache::lonnet::unserialize($reply)};
+        } else {
+            my $reply = &get_dom("getdom:$cdom:$dbname:$name");
+            my $encref = &Apache::lonnet::thaw_unescape($reply);
+            if (ref($encref) eq 'HASH') {
+                %ltienc = %{$encref};
+            }
+        }
+        my $cachetime = 24*60*60;
+        &Apache::lonnet::do_cache_new($cachename,$hashid,\%ltienc,$cachetime);
+    }
+    if (!keys(%ltienc)) {
+         return ();
+    } elsif (exists($ltienc{$idx})) {
+        if (ref($ltienc{$idx}) eq 'HASH') {
+            if (exists($ltienc{$idx}{'key'})) {
+                $key = $ltienc{$idx}{'key'};
+            }
+            if (exists($ltienc{$idx}{'secret'})) {
+                $secret = $ltienc{$idx}{'secret'};
+                if ($keynum =~ /^\d+$/) {
+                    my $privhost;
+                    my $privname = 'ltitools';
+                    if (($type eq 'lti') || ($type eq 'linkprot')) {
+                        $privname = 'lti';
+                    }
+                    if ($crsdef) {
+                        my $primary = &Apache::lonnet::domain($cdom,'primary');
+                        my @ids = &Apache::lonnet::current_machine_ids();
+                        unless (grep(/^\Q$primary\E$/,@ids)) {
+                            $privhost = $primary;
+                            my ($result,$plainsecret) = &decrypt_secret($privhost,$secret,$keynum,$privname);
+                            if ($result eq 'ok') {
+                                $secret = $plainsecret;
+                            } else {
+                                undef($secret);
+                            }
+                        }
+                    }
+                    unless ($privhost) {
+                        my $privkey = &get_dom("getdom:$cdom:private:$keynum:$privname:key");
+                        if (($privkey ne '') && ($secret ne '')) {
+                            my $cipher = new Crypt::CBC($privkey);
+                            $secret = $cipher->decrypt_hex($secret);
+                        } else {
+                            undef($secret);
+                        }
+                    }
+                }
+            }
+        }
+    }
+    return ($key,$secret);
+}
+
+sub decrypt_secret {
+    my ($privhost,$secret,$keynum,$type) = @_;
+    return;
+}
+
 1;
 
 __END__
@@ -1169,7 +1564,7 @@ in /home/httpd/lonUsers/$dom on the prim
 The single argument passed is the string: $cmd:$udom:$namespace:$what
 where $cmd is the command historically passed to lond - i.e., getdom
 or egetdom, $udom is the domain, $namespace is the name of the GDBM file
-(encconfig or configuration), and $what is a string containing names of
+(encconfig or configuration), and $what is a string containing names of 
 items to retrieve from the db file (each item name is escaped and separated
 from the next item name with an ampersand). The return value is either:
 error: followed by an error message, or a string containing the value (escaped)