src/encrypted_kdm.cc

   1 /*
   2     Copyright (C) 2013-2015 Carl Hetherington <cth@carlh.net>
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include "encrypted_kdm.h"
  21 #include "util.h"
  22 #include "certificate_chain.h"
  23 #include <libcxml/cxml.h>
  24 #include <libxml++/document.h>
  25 #include <libxml++/nodes/element.h>
  26 #include <libxml/parser.h>
  27 #include <boost/date_time/posix_time/posix_time.hpp>
  28 #include <boost/foreach.hpp>
  29
  30 using std::list;
  31 using std::vector;
  32 using std::string;
  33 using std::map;
  34 using std::pair;
  35 using boost::shared_ptr;
  36 using namespace dcp;
  37
  38 namespace dcp {
  39
  40 /** Namespace for classes used to hold our data; they are internal to this .cc file */
  41 namespace data {
  42
  43 class Signer
  44 {
  45 public:
  46         Signer () {}
  47
  48         Signer (shared_ptr<const cxml::Node> node)
  49                 : x509_issuer_name (node->string_child ("X509IssuerName"))
  50                 , x509_serial_number (node->string_child ("X509SerialNumber"))
  51         {
  52
  53         }
  54
  55         void as_xml (xmlpp::Element* node) const
  56         {
  57                 node->add_child("X509IssuerName", "ds")->add_child_text (x509_issuer_name);
  58                 node->add_child("X509SerialNumber", "ds")->add_child_text (x509_serial_number);
  59         }
  60
  61         string x509_issuer_name;
  62         string x509_serial_number;
  63 };
  64
  65 class X509Data
  66 {
  67 public:
  68         X509Data () {}
  69
  70         X509Data (boost::shared_ptr<const cxml::Node> node)
  71                 : x509_issuer_serial (Signer (node->node_child ("X509IssuerSerial")))
  72                 , x509_certificate (node->string_child ("X509Certificate"))
  73         {
  74                 node->done ();
  75         }
  76
  77         void as_xml (xmlpp::Element* node) const
  78         {
  79                 x509_issuer_serial.as_xml (node->add_child ("X509IssuerSerial", "ds"));
  80                 node->add_child("X509Certificate", "ds")->add_child_text (x509_certificate);
  81         }
  82
  83         Signer x509_issuer_serial;
  84         std::string x509_certificate;
  85 };
  86
  87 class Reference
  88 {
  89 public:
  90         Reference () {}
  91
  92         Reference (string u)
  93                 : uri (u)
  94         {}
  95
  96         Reference (shared_ptr<const cxml::Node> node)
  97                 : uri (node->string_attribute ("URI"))
  98                 , digest_value (node->string_child ("DigestValue"))
  99         {
 100
 101         }
 102
 103         void as_xml (xmlpp::Element* node) const
 104         {
 105                 node->set_attribute ("URI", uri);
 106                 node->add_child("DigestMethod", "ds")->set_attribute ("Algorithm", "http://www.w3.org/2001/04/xmlenc#sha256");
 107                 node->add_child("DigestValue", "ds")->add_child_text (digest_value);
 108         }
 109
 110         string uri;
 111         string digest_value;
 112 };
 113
 114 class SignedInfo
 115 {
 116 public:
 117         SignedInfo ()
 118                 : authenticated_public ("#ID_AuthenticatedPublic")
 119                 , authenticated_private ("#ID_AuthenticatedPrivate")
 120         {}
 121
 122         SignedInfo (shared_ptr<const cxml::Node> node)
 123         {
 124                 list<shared_ptr<cxml::Node> > references = node->node_children ("Reference");
 125                 for (list<shared_ptr<cxml::Node> >::const_iterator i = references.begin(); i != references.end(); ++i) {
 126                         if ((*i)->string_attribute ("URI") == "#ID_AuthenticatedPublic") {
 127                                 authenticated_public = Reference (*i);
 128                         } else if ((*i)->string_attribute ("URI") == "#ID_AuthenticatedPrivate") {
 129                                 authenticated_private = Reference (*i);
 130                         }
 131
 132                         /* XXX: do something if we don't recognise the node */
 133                 }
 134         }
 135
 136         void as_xml (xmlpp::Element* node) const
 137         {
 138                 node->add_child ("CanonicalizationMethod", "ds")->set_attribute (
 139                         "Algorithm", "http://www.w3.org/TR/2001/REC-xml-c14n-20010315#WithComments"
 140                         );
 141
 142                 node->add_child ("SignatureMethod", "ds")->set_attribute (
 143                         "Algorithm", "http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"
 144                         );
 145
 146                 authenticated_public.as_xml (node->add_child ("Reference", "ds"));
 147                 authenticated_private.as_xml (node->add_child ("Reference", "ds"));
 148         }
 149
 150 private:
 151         Reference authenticated_public;
 152         Reference authenticated_private;
 153 };
 154
 155 class Signature
 156 {
 157 public:
 158         Signature () {}
 159
 160         Signature (shared_ptr<const cxml::Node> node)
 161                 : signed_info (node->node_child ("SignedInfo"))
 162                 , signature_value (node->string_child ("SignatureValue"))
 163         {
 164                 list<shared_ptr<cxml::Node> > x509_data_nodes = node->node_child("KeyInfo")->node_children ("X509Data");
 165                 for (list<shared_ptr<cxml::Node> >::const_iterator i = x509_data_nodes.begin(); i != x509_data_nodes.end(); ++i) {
 166                         x509_data.push_back (X509Data (*i));
 167                 }
 168         }
 169
 170         void as_xml (xmlpp::Node* node) const
 171         {
 172                 signed_info.as_xml (node->add_child ("SignedInfo", "ds"));
 173                 node->add_child("SignatureValue", "ds")->add_child_text (signature_value);
 174
 175                 xmlpp::Element* key_info_node = node->add_child ("KeyInfo", "ds");
 176                 for (std::list<X509Data>::const_iterator i = x509_data.begin(); i != x509_data.end(); ++i) {
 177                         i->as_xml (key_info_node->add_child ("X509Data", "ds"));
 178                 }
 179         }
 180
 181         SignedInfo signed_info;
 182         string signature_value;
 183         list<X509Data> x509_data;
 184 };
 185
 186 class AuthenticatedPrivate
 187 {
 188 public:
 189         AuthenticatedPrivate () {}
 190
 191         AuthenticatedPrivate (shared_ptr<const cxml::Node> node)
 192         {
 193                 list<shared_ptr<cxml::Node> > encrypted_key_nodes = node->node_children ("EncryptedKey");
 194                 for (list<shared_ptr<cxml::Node> >::const_iterator i = encrypted_key_nodes.begin(); i != encrypted_key_nodes.end(); ++i) {
 195                         encrypted_key.push_back ((*i)->node_child("CipherData")->string_child ("CipherValue"));
 196                 }
 197         }
 198
 199         void as_xml (xmlpp::Element* node, map<string, xmlpp::Attribute *>& references) const
 200         {
 201                 references["ID_AuthenticatedPrivate"] = node->set_attribute ("Id", "ID_AuthenticatedPrivate");
 202
 203                 for (list<string>::const_iterator i = encrypted_key.begin(); i != encrypted_key.end(); ++i) {
 204                         xmlpp::Element* encrypted_key = node->add_child ("EncryptedKey", "enc");
 205                         xmlpp::Element* encryption_method = encrypted_key->add_child ("EncryptionMethod", "enc");
 206                         encryption_method->set_attribute ("Algorithm", "http://www.w3.org/2001/04/xmlenc#rsa-oaep-mgf1p");
 207                         xmlpp::Element* digest_method = encryption_method->add_child ("DigestMethod", "ds");
 208                         digest_method->set_attribute ("Algorithm", "http://www.w3.org/2000/09/xmldsig#sha1");
 209                         xmlpp::Element* cipher_data = encrypted_key->add_child ("CipherData", "enc");
 210                         cipher_data->add_child("CipherValue", "enc")->add_child_text (*i);
 211                 }
 212         }
 213
 214         list<string> encrypted_key;
 215 };
 216
 217 class TypedKeyId
 218 {
 219 public:
 220         TypedKeyId () {}
 221
 222         TypedKeyId (shared_ptr<const cxml::Node> node)
 223                 : key_type (node->string_child ("KeyType"))
 224                 , key_id (remove_urn_uuid (node->string_child ("KeyId")))
 225         {
 226
 227         }
 228
 229         TypedKeyId (string type, string id)
 230                 : key_type (type)
 231                 , key_id (id)
 232         {}
 233
 234         void as_xml (xmlpp::Element* node) const
 235         {
 236                 xmlpp::Element* type = node->add_child("KeyType");
 237                 type->add_child_text (key_type);
 238                 node->add_child("KeyId")->add_child_text ("urn:uuid:" + key_id);
 239                 /* XXX: this feels like a bit of a hack */
 240                 if (key_type == "MDEK") {
 241                         type->set_attribute ("scope", "http://www.dolby.com/cp850/2012/KDM#kdm-key-type");
 242                 }
 243         }
 244
 245         string key_type;
 246         string key_id;
 247 };
 248
 249 class KeyIdList
 250 {
 251 public:
 252         KeyIdList () {}
 253
 254         KeyIdList (shared_ptr<const cxml::Node> node)
 255         {
 256                 list<shared_ptr<cxml::Node> > typed_key_id_nodes = node->node_children ("TypedKeyId");
 257                 for (list<shared_ptr<cxml::Node> >::const_iterator i = typed_key_id_nodes.begin(); i != typed_key_id_nodes.end(); ++i) {
 258                         typed_key_id.push_back (TypedKeyId (*i));
 259                 }
 260         }
 261
 262         void as_xml (xmlpp::Element* node) const
 263         {
 264                 for (list<TypedKeyId>::const_iterator i = typed_key_id.begin(); i != typed_key_id.end(); ++i) {
 265                         i->as_xml (node->add_child("TypedKeyId"));
 266                 }
 267         }
 268
 269         list<TypedKeyId> typed_key_id;
 270 };
 271
 272 class AuthorizedDeviceInfo
 273 {
 274 public:
 275         AuthorizedDeviceInfo () {}
 276
 277         AuthorizedDeviceInfo (shared_ptr<const cxml::Node> node)
 278                 : device_list_identifier (remove_urn_uuid (node->string_child ("DeviceListIdentifier")))
 279                 , device_list_description (node->optional_string_child ("DeviceListDescription"))
 280         {
 281                 BOOST_FOREACH (cxml::ConstNodePtr i, node->node_child("DeviceList")->node_children("CertificateThumbprint")) {
 282                         certificate_thumbprints.push_back (i->content ());
 283                 }
 284         }
 285
 286         void as_xml (xmlpp::Element* node) const
 287         {
 288                 node->add_child ("DeviceListIdentifier")->add_child_text ("urn:uuid:" + device_list_identifier);
 289                 if (device_list_description) {
 290                         node->add_child ("DeviceListDescription")->add_child_text (device_list_description.get());
 291                 }
 292                 xmlpp::Element* device_list = node->add_child ("DeviceList");
 293                 BOOST_FOREACH (string i, certificate_thumbprints) {
 294                         device_list->add_child("CertificateThumbprint")->add_child_text (i);
 295                 }
 296         }
 297
 298         /** DeviceListIdentifier without the urn:uuid: prefix */
 299         string device_list_identifier;
 300         boost::optional<string> device_list_description;
 301         std::list<string> certificate_thumbprints;
 302 };
 303
 304 class X509IssuerSerial
 305 {
 306 public:
 307         X509IssuerSerial () {}
 308
 309         X509IssuerSerial (shared_ptr<const cxml::Node> node)
 310                 : x509_issuer_name (node->string_child ("X509IssuerName"))
 311                 , x509_serial_number (node->string_child ("X509SerialNumber"))
 312         {
 313
 314         }
 315
 316         void as_xml (xmlpp::Element* node) const
 317         {
 318                 node->add_child("X509IssuerName", "ds")->add_child_text (x509_issuer_name);
 319                 node->add_child("X509SerialNumber", "ds")->add_child_text (x509_serial_number);
 320         }
 321
 322         string x509_issuer_name;
 323         string x509_serial_number;
 324 };
 325
 326 class Recipient
 327 {
 328 public:
 329         Recipient () {}
 330
 331         Recipient (shared_ptr<const cxml::Node> node)
 332                 : x509_issuer_serial (node->node_child ("X509IssuerSerial"))
 333                 , x509_subject_name (node->string_child ("X509SubjectName"))
 334         {
 335
 336         }
 337
 338         void as_xml (xmlpp::Element* node) const
 339         {
 340                 x509_issuer_serial.as_xml (node->add_child ("X509IssuerSerial"));
 341                 node->add_child("X509SubjectName")->add_child_text (x509_subject_name);
 342         }
 343
 344         X509IssuerSerial x509_issuer_serial;
 345         string x509_subject_name;
 346 };
 347
 348 class KDMRequiredExtensions
 349 {
 350 public:
 351         KDMRequiredExtensions () {}
 352
 353         KDMRequiredExtensions (shared_ptr<const cxml::Node> node)
 354                 : recipient (node->node_child ("Recipient"))
 355                 , composition_playlist_id (remove_urn_uuid (node->string_child ("CompositionPlaylistId")))
 356                 , content_title_text (node->string_child ("ContentTitleText"))
 357                 , not_valid_before (node->string_child ("ContentKeysNotValidBefore"))
 358                 , not_valid_after (node->string_child ("ContentKeysNotValidAfter"))
 359                 , authorized_device_info (node->node_child ("AuthorizedDeviceInfo"))
 360                 , key_id_list (node->node_child ("KeyIdList"))
 361         {
 362
 363         }
 364
 365         void as_xml (xmlpp::Element* node) const
 366         {
 367                 node->set_attribute ("xmlns", "http://www.smpte-ra.org/schemas/430-1/2006/KDM");
 368
 369                 recipient.as_xml (node->add_child ("Recipient"));
 370                 node->add_child("CompositionPlaylistId")->add_child_text ("urn:uuid:" + composition_playlist_id);
 371                 node->add_child("ContentTitleText")->add_child_text (content_title_text);
 372                 if (content_authenticator) {
 373                         node->add_child("ContentAuthenticator")->add_child_text (content_authenticator.get ());
 374                 }
 375                 node->add_child("ContentKeysNotValidBefore")->add_child_text (not_valid_before.as_string ());
 376                 node->add_child("ContentKeysNotValidAfter")->add_child_text (not_valid_after.as_string ());
 377                 authorized_device_info.as_xml (node->add_child ("AuthorizedDeviceInfo"));
 378                 key_id_list.as_xml (node->add_child ("KeyIdList"));
 379
 380                 xmlpp::Element* forensic_mark_flag_list = node->add_child ("ForensicMarkFlagList");
 381                 forensic_mark_flag_list->add_child("ForensicMarkFlag")->add_child_text ("http://www.smpte-ra.org/430-1/2006/KDM#mrkflg-picture-disable");
 382                 forensic_mark_flag_list->add_child("ForensicMarkFlag")->add_child_text ("http://www.smpte-ra.org/430-1/2006/KDM#mrkflg-audio-disable");
 383         }
 384
 385         Recipient recipient;
 386         string composition_playlist_id;
 387         boost::optional<string> content_authenticator;
 388         string content_title_text;
 389         LocalTime not_valid_before;
 390         LocalTime not_valid_after;
 391         AuthorizedDeviceInfo authorized_device_info;
 392         KeyIdList key_id_list;
 393 };
 394
 395 class RequiredExtensions
 396 {
 397 public:
 398         RequiredExtensions () {}
 399
 400         RequiredExtensions (shared_ptr<const cxml::Node> node)
 401                 : kdm_required_extensions (node->node_child ("KDMRequiredExtensions"))
 402         {
 403
 404         }
 405
 406         void as_xml (xmlpp::Element* node) const
 407         {
 408                 kdm_required_extensions.as_xml (node->add_child ("KDMRequiredExtensions"));
 409         }
 410
 411         KDMRequiredExtensions kdm_required_extensions;
 412 };
 413
 414 class AuthenticatedPublic
 415 {
 416 public:
 417         AuthenticatedPublic ()
 418                 : message_id (make_uuid ())
 419                 , issue_date (LocalTime().as_string ())
 420         {}
 421
 422         AuthenticatedPublic (shared_ptr<const cxml::Node> node)
 423                 : message_id (remove_urn_uuid (node->string_child ("MessageId")))
 424                 , annotation_text (node->string_child ("AnnotationText"))
 425                 , issue_date (node->string_child ("IssueDate"))
 426                 , signer (node->node_child ("Signer"))
 427                 , required_extensions (node->node_child ("RequiredExtensions"))
 428         {
 429
 430         }
 431
 432         void as_xml (xmlpp::Element* node, map<string, xmlpp::Attribute *>& references) const
 433         {
 434                 references["ID_AuthenticatedPublic"] = node->set_attribute ("Id", "ID_AuthenticatedPublic");
 435
 436                 node->add_child("MessageId")->add_child_text ("urn:uuid:" + message_id);
 437                 node->add_child("MessageType")->add_child_text ("http://www.smpte-ra.org/430-1/2006/KDM#kdm-key-type");
 438                 node->add_child("AnnotationText")->add_child_text (annotation_text);
 439                 node->add_child("IssueDate")->add_child_text (issue_date);
 440
 441                 signer.as_xml (node->add_child ("Signer"));
 442                 required_extensions.as_xml (node->add_child ("RequiredExtensions"));
 443
 444                 node->add_child ("NonCriticalExtensions");
 445         }
 446
 447         string message_id;
 448         string annotation_text;
 449         string issue_date;
 450         Signer signer;
 451         RequiredExtensions required_extensions;
 452 };
 453
 454 /** Class to describe our data.  We use a class hierarchy as it's a bit nicer
 455  *  for XML data than a flat description.
 456  */
 457 class EncryptedKDMData
 458 {
 459 public:
 460         EncryptedKDMData ()
 461         {
 462
 463         }
 464
 465         EncryptedKDMData (shared_ptr<const cxml::Node> node)
 466                 : authenticated_public (node->node_child ("AuthenticatedPublic"))
 467                 , authenticated_private (node->node_child ("AuthenticatedPrivate"))
 468                 , signature (node->node_child ("Signature"))
 469         {
 470
 471         }
 472
 473         shared_ptr<xmlpp::Document> as_xml () const
 474         {
 475                 shared_ptr<xmlpp::Document> document (new xmlpp::Document ());
 476                 xmlpp::Element* root = document->create_root_node ("DCinemaSecurityMessage", "http://www.smpte-ra.org/schemas/430-3/2006/ETM");
 477                 root->set_namespace_declaration ("http://www.w3.org/2000/09/xmldsig#", "ds");
 478                 root->set_namespace_declaration ("http://www.w3.org/2001/04/xmlenc#", "enc");
 479                 map<string, xmlpp::Attribute *> references;
 480                 authenticated_public.as_xml (root->add_child ("AuthenticatedPublic"), references);
 481                 authenticated_private.as_xml (root->add_child ("AuthenticatedPrivate"), references);
 482                 signature.as_xml (root->add_child ("Signature", "ds"));
 483
 484                 for (map<string, xmlpp::Attribute*>::const_iterator i = references.begin(); i != references.end(); ++i) {
 485                         xmlAddID (0, document->cobj(), (const xmlChar *) i->first.c_str(), i->second->cobj ());
 486                 }
 487
 488                 return document;
 489         }
 490
 491         AuthenticatedPublic authenticated_public;
 492         AuthenticatedPrivate authenticated_private;
 493         Signature signature;
 494 };
 495
 496 }
 497 }
 498
 499 EncryptedKDM::EncryptedKDM (string s)
 500 {
 501         shared_ptr<cxml::Document> doc (new cxml::Document ("DCinemaSecurityMessage"));
 502         doc->read_string (s);
 503         _data = new data::EncryptedKDMData (doc);
 504 }
 505
 506 EncryptedKDM::EncryptedKDM (
 507         shared_ptr<const CertificateChain> signer,
 508         Certificate recipient,
 509         vector<Certificate> trusted_devices,
 510         string device_list_description,
 511         string cpl_id,
 512         string content_title_text,
 513         LocalTime not_valid_before,
 514         LocalTime not_valid_after,
 515         Formulation formulation,
 516         list<pair<string, string> > key_ids,
 517         list<string> keys
 518         )
 519         : _data (new data::EncryptedKDMData)
 520 {
 521         /* Fill our XML-ish description in with the juicy bits that the caller has given */
 522
 523         data::AuthenticatedPublic& aup = _data->authenticated_public;
 524         aup.signer.x509_issuer_name = signer->leaf().issuer ();
 525         aup.signer.x509_serial_number = signer->leaf().serial ();
 526
 527         data::KDMRequiredExtensions& kre = _data->authenticated_public.required_extensions.kdm_required_extensions;
 528         kre.recipient.x509_issuer_serial.x509_issuer_name = recipient.issuer ();
 529         kre.recipient.x509_issuer_serial.x509_serial_number = recipient.serial ();
 530         kre.recipient.x509_subject_name = recipient.subject ();
 531         kre.authorized_device_info.device_list_description = device_list_description;
 532         kre.composition_playlist_id = cpl_id;
 533         if (formulation == DCI_ANY || formulation == DCI_SPECIFIC) {
 534                 kre.content_authenticator = signer->leaf().thumbprint ();
 535         }
 536         kre.content_title_text = content_title_text;
 537         kre.not_valid_before = not_valid_before;
 538         kre.not_valid_after = not_valid_after;
 539         kre.authorized_device_info.device_list_identifier = make_uuid ();
 540         string n = recipient.subject_common_name ();
 541         if (n.find (".") != string::npos) {
 542                 n = n.substr (n.find (".") + 1);
 543         }
 544         kre.authorized_device_info.device_list_description = n;
 545
 546         if (formulation == MODIFIED_TRANSITIONAL_1 || formulation == DCI_ANY) {
 547                 /* Use the "assume trust" thumbprint */
 548                 kre.authorized_device_info.certificate_thumbprints.push_back ("2jmj7l5rSw0yVb/vlWAYkK/YBwk=");
 549         } else if (formulation == DCI_SPECIFIC) {
 550                 /* As I read the standard we should use the recipient
 551                    /and/ other trusted device thumbprints here.  MJD
 552                    reports that this doesn't work with his setup;
 553                    a working KDM does not include the recipient's
 554                    thumbprint (recipient.thumbprint()).
 555                 */
 556                 BOOST_FOREACH (Certificate const & i, trusted_devices) {
 557                         kre.authorized_device_info.certificate_thumbprints.push_back (i.thumbprint ());
 558                 }
 559         }
 560
 561         for (list<pair<string, string> >::const_iterator i = key_ids.begin(); i != key_ids.end(); ++i) {
 562                 kre.key_id_list.typed_key_id.push_back (data::TypedKeyId (i->first, i->second));
 563         }
 564
 565         _data->authenticated_private.encrypted_key = keys;
 566
 567         /* Read the XML so far and sign it */
 568         shared_ptr<xmlpp::Document> doc = _data->as_xml ();
 569         xmlpp::Node::NodeList children = doc->get_root_node()->get_children ();
 570         for (xmlpp::Node::NodeList::const_iterator i = children.begin(); i != children.end(); ++i) {
 571                 if ((*i)->get_name() == "Signature") {
 572                         signer->add_signature_value (*i, "ds");
 573                 }
 574         }
 575
 576         /* Read the bits that add_signature_value did back into our variables */
 577         shared_ptr<cxml::Node> signed_doc (new cxml::Node (doc->get_root_node ()));
 578         _data->signature = data::Signature (signed_doc->node_child ("Signature"));
 579 }
 580
 581 EncryptedKDM::EncryptedKDM (EncryptedKDM const & other)
 582         : _data (new data::EncryptedKDMData (*other._data))
 583 {
 584
 585 }
 586
 587 EncryptedKDM &
 588 EncryptedKDM::operator= (EncryptedKDM const & other)
 589 {
 590         if (this == &other) {
 591                 return *this;
 592         }
 593
 594         delete _data;
 595         _data = new data::EncryptedKDMData (*other._data);
 596         return *this;
 597 }
 598
 599 EncryptedKDM::~EncryptedKDM ()
 600 {
 601         delete _data;
 602 }
 603
 604 void
 605 EncryptedKDM::as_xml (boost::filesystem::path path) const
 606 {
 607         FILE* f = fopen_boost (path, "w");
 608         string const x = as_xml ();
 609         fwrite (x.c_str(), 1, x.length(), f);
 610         fclose (f);
 611 }
 612
 613 string
 614 EncryptedKDM::as_xml () const
 615 {
 616         return _data->as_xml()->write_to_string ("UTF-8");
 617 }
 618
 619 list<string>
 620 EncryptedKDM::keys () const
 621 {
 622         return _data->authenticated_private.encrypted_key;
 623 }
 624
 625 string
 626 EncryptedKDM::annotation_text () const
 627 {
 628         return _data->authenticated_public.annotation_text;
 629 }
 630
 631 string
 632 EncryptedKDM::content_title_text () const
 633 {
 634         return _data->authenticated_public.required_extensions.kdm_required_extensions.content_title_text;
 635 }
 636
 637 string
 638 EncryptedKDM::cpl_id () const
 639 {
 640         return _data->authenticated_public.required_extensions.kdm_required_extensions.composition_playlist_id;
 641 }
 642
 643 string
 644 EncryptedKDM::issue_date () const
 645 {
 646         return _data->authenticated_public.issue_date;
 647 }
 648
 649 bool
 650 dcp::operator== (EncryptedKDM const & a, EncryptedKDM const & b)
 651 {
 652         /* Not exactly efficient... */
 653         return a.as_xml() == b.as_xml();
 654 }