PVE::Ticket - new helper class to create auth tickets

[pve-common.git] / src / PVE / Ticket.pm

diff --git a/src/PVE/Ticket.pm b/src/PVE/Ticket.pm
new file mode 100644 (file)
index 0000000..76d2ea5
--- /dev/null
+++ b/src/PVE/Ticket.pm
@@ -0,0 +1,164 @@
+package PVE::Ticket;
+
+use strict;
+use warnings;
+
+use Crypt::OpenSSL::Random;
+use Crypt::OpenSSL::RSA;
+use MIME::Base64;
+use MIME::Base32; #libmime-base32-perl
+use Digest::SHA;
+use Time::HiRes qw(gettimeofday);
+
+use PVE::Exception qw(raise_perm_exc);
+
+Crypt::OpenSSL::RSA->import_random_seed();
+
+sub assemble_csrf_prevention_token {
+    my ($secret, $username) = @_;
+
+    my $timestamp = sprintf("%08X", time());
+
+    my $digest = Digest::SHA::sha1_base64("$timestamp:$username", $secret);
+
+    return "$timestamp:$digest";
+}
+
+sub verify_csrf_prevention_token {
+    my ($secret, $username, $token, $min_age, $max_age, $noerr) = @_;
+
+    if ($token =~ m/^([A-Z0-9]{8}):(\S+)$/) {
+       my $sig = $2;
+       my $timestamp = $1;
+       my $ttime = hex($timestamp);
+
+       my $digest = Digest::SHA::sha1_base64("$timestamp:$username", $secret);
+
+       my $age = time() - $ttime;
+       return 1 if ($digest eq $sig) && ($age > $min_age) &&
+           ($age < $max_age);
+    }
+
+    raise_perm_exc("Permission denied - invalid csrf token") if !$noerr;
+
+    return undef;
+}
+
+# Note: data may not contain white spaces (verify fails in that case)
+sub assemble_rsa_ticket {
+    my ($rsa_priv, $prefix, $data, $secret_data) = @_;
+
+    my $timestamp = sprintf("%08X", time());
+
+    my $plain = "$prefix:";
+
+    $plain .= "$data:" if defined($data);
+
+    $plain .= $timestamp;
+
+    my $full = defined($secret_data) ? "$plain:$secret_data" : $plain;
+
+    my $ticket = $plain . "::" . encode_base64($rsa_priv->sign($full), '');
+
+    return $ticket;
+}
+
+sub verify_rsa_ticket {
+    my ($rsa_pub, $prefix, $ticket, $secret_data, $min_age, $max_age, $noerr) = @_;
+
+    if ($ticket && $ticket =~ m/^(\Q$prefix\E:\S+)::([^:\s]+)$/) {
+       my $plain = $1;
+       my $sig = $2;
+
+       my $full = defined($secret_data) ? "$plain:$secret_data" : $plain;
+
+       if ($rsa_pub->verify($full, decode_base64($sig))) {
+           if ($plain =~ m/^\Q$prefix\E:(?:(\S+):)?([A-Z0-9]{8})$/) {
+               my $data = $1; # Note: not all tickets contains data
+               my $timestamp = $2;
+               my $ttime = hex($timestamp);
+
+               my $age = time() - $ttime;
+
+               if (($age > $min_age) && ($age < $max_age)) {
+                   if (defined($data)) {
+                       return wantarray ? ($data, $age) : $data;
+                   } else {
+                       return wantarray ? (1, $age) : 1;
+                   }
+               }
+           }
+       }
+    }
+
+    raise_perm_exc("permission denied - invalid $prefix ticket") if !$noerr;
+
+    return undef;
+}
+
+sub assemble_spice_ticket {
+    my ($secret, $username, $vmid, $node) = @_;
+
+    my ($seconds, $microseconds) = gettimeofday;
+
+    my $timestamp = sprintf("%08x", $seconds);
+
+    my $randomstr = "PVESPICE:$timestamp:$username:$vmid:$node:$secret:" .
+       ':' . sprintf("%08x", $microseconds) .
+       ':' . sprintf("%08x", $$) .
+       ':' . rand(1);
+
+    # this should be used as one-time password
+    # max length is 60 chars (spice limit)
+    # we pass this to qemu set_pasword and limit lifetime there
+    # keep this secret
+    my $ticket = Digest::SHA::sha1_hex($randomstr);
+
+    # Note: spice proxy connects with HTTP, so $proxyticket is exposed to public
+    # we use a signature/timestamp to make sure nobody can fake such a ticket
+    # an attacker can use this $proxyticket, but he will fail because $ticket is
+    # private.
+    # The proxy needs to be able to extract/verify the ticket
+    # Note: data needs to be lower case only, because virt-viewer needs that
+    # Note: RSA signature are too long (>=256 charaters) and make problems with remote-viewer
+
+    my $plain = "pvespiceproxy:$timestamp:$vmid:" . lc($node);
+
+    # produces 40 characters
+    my $sig = unpack("H*", Digest::SHA::sha1($plain, $secret));
+
+    #my $sig =  unpack("H*", $rsa_priv->sign($plain)); # this produce too long strings (512)
+
+    my $proxyticket = "$plain::$sig";
+
+    return ($ticket, $proxyticket);
+}
+
+sub verify_spice_connect_url {
+    my ($secret, $connect_str) = @_;
+
+    # Note: we pass the spice ticket as 'host', so the
+    # spice viewer connects with "$ticket:$port"
+
+    return undef if !$connect_str;
+
+    if ($connect_str =~m/^pvespiceproxy:([a-z0-9]{8}):(\d+):(\S+)::([a-z0-9]{40}):(\d+)$/) {
+       my ($timestamp, $vmid, $node, $hexsig, $port) = ($1, $2, $3, $4, $5, $6);
+       my $ttime = hex($timestamp);
+       my $age = time() - $ttime;
+
+       # use very limited lifetime - is this enough?
+       return undef if !(($age > -20) && ($age < 40));
+
+       my $plain = "pvespiceproxy:$timestamp:$vmid:$node";
+       my $sig = unpack("H*", Digest::SHA::sha1($plain, $secret));
+
+       if ($sig eq $hexsig) {
+           return ($vmid, $node, $port);
+       }
+    }
+
+    return undef;
+}
+
+1;