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diff --git a/node_modules/node-forge/lib/pkcs7.js b/node_modules/node-forge/lib/pkcs7.js
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+/**
+ * Javascript implementation of PKCS#7 v1.5.
+ *
+ * @author Stefan Siegl
+ * @author Dave Longley
+ *
+ * Copyright (c) 2012 Stefan Siegl <stesie@brokenpipe.de>
+ * Copyright (c) 2012-2015 Digital Bazaar, Inc.
+ *
+ * Currently this implementation only supports ContentType of EnvelopedData,
+ * EncryptedData, or SignedData at the root level. The top level elements may
+ * contain only a ContentInfo of ContentType Data, i.e. plain data. Further
+ * nesting is not (yet) supported.
+ *
+ * The Forge validators for PKCS #7's ASN.1 structures are available from
+ * a separate file pkcs7asn1.js, since those are referenced from other
+ * PKCS standards like PKCS #12.
+ */
+var forge = require('./forge');
+require('./aes');
+require('./asn1');
+require('./des');
+require('./oids');
+require('./pem');
+require('./pkcs7asn1');
+require('./random');
+require('./util');
+require('./x509');
+
+// shortcut for ASN.1 API
+var asn1 = forge.asn1;
+
+// shortcut for PKCS#7 API
+var p7 = module.exports = forge.pkcs7 = forge.pkcs7 || {};
+
+/**
+ * Converts a PKCS#7 message from PEM format.
+ *
+ * @param pem the PEM-formatted PKCS#7 message.
+ *
+ * @return the PKCS#7 message.
+ */
+p7.messageFromPem = function(pem) {
+  var msg = forge.pem.decode(pem)[0];
+
+  if(msg.type !== 'PKCS7') {
+    var error = new Error('Could not convert PKCS#7 message from PEM; PEM ' +
+      'header type is not "PKCS#7".');
+    error.headerType = msg.type;
+    throw error;
+  }
+  if(msg.procType && msg.procType.type === 'ENCRYPTED') {
+    throw new Error('Could not convert PKCS#7 message from PEM; PEM is encrypted.');
+  }
+
+  // convert DER to ASN.1 object
+  var obj = asn1.fromDer(msg.body);
+
+  return p7.messageFromAsn1(obj);
+};
+
+/**
+ * Converts a PKCS#7 message to PEM format.
+ *
+ * @param msg The PKCS#7 message object
+ * @param maxline The maximum characters per line, defaults to 64.
+ *
+ * @return The PEM-formatted PKCS#7 message.
+ */
+p7.messageToPem = function(msg, maxline) {
+  // convert to ASN.1, then DER, then PEM-encode
+  var pemObj = {
+    type: 'PKCS7',
+    body: asn1.toDer(msg.toAsn1()).getBytes()
+  };
+  return forge.pem.encode(pemObj, {maxline: maxline});
+};
+
+/**
+ * Converts a PKCS#7 message from an ASN.1 object.
+ *
+ * @param obj the ASN.1 representation of a ContentInfo.
+ *
+ * @return the PKCS#7 message.
+ */
+p7.messageFromAsn1 = function(obj) {
+  // validate root level ContentInfo and capture data
+  var capture = {};
+  var errors = [];
+  if(!asn1.validate(obj, p7.asn1.contentInfoValidator, capture, errors)) {
+    var error = new Error('Cannot read PKCS#7 message. ' +
+      'ASN.1 object is not an PKCS#7 ContentInfo.');
+    error.errors = errors;
+    throw error;
+  }
+
+  var contentType = asn1.derToOid(capture.contentType);
+  var msg;
+
+  switch(contentType) {
+    case forge.pki.oids.envelopedData:
+      msg = p7.createEnvelopedData();
+      break;
+
+    case forge.pki.oids.encryptedData:
+      msg = p7.createEncryptedData();
+      break;
+
+    case forge.pki.oids.signedData:
+      msg = p7.createSignedData();
+      break;
+
+    default:
+      throw new Error('Cannot read PKCS#7 message. ContentType with OID ' +
+        contentType + ' is not (yet) supported.');
+  }
+
+  msg.fromAsn1(capture.content.value[0]);
+  return msg;
+};
+
+p7.createSignedData = function() {
+  var msg = null;
+  msg = {
+    type: forge.pki.oids.signedData,
+    version: 1,
+    certificates: [],
+    crls: [],
+    // TODO: add json-formatted signer stuff here?
+    signers: [],
+    // populated during sign()
+    digestAlgorithmIdentifiers: [],
+    contentInfo: null,
+    signerInfos: [],
+
+    fromAsn1: function(obj) {
+      // validate SignedData content block and capture data.
+      _fromAsn1(msg, obj, p7.asn1.signedDataValidator);
+      msg.certificates = [];
+      msg.crls = [];
+      msg.digestAlgorithmIdentifiers = [];
+      msg.contentInfo = null;
+      msg.signerInfos = [];
+
+      if(msg.rawCapture.certificates) {
+        var certs = msg.rawCapture.certificates.value;
+        for(var i = 0; i < certs.length; ++i) {
+          msg.certificates.push(forge.pki.certificateFromAsn1(certs[i]));
+        }
+      }
+
+      // TODO: parse crls
+    },
+
+    toAsn1: function() {
+      // degenerate case with no content
+      if(!msg.contentInfo) {
+        msg.sign();
+      }
+
+      var certs = [];
+      for(var i = 0; i < msg.certificates.length; ++i) {
+        certs.push(forge.pki.certificateToAsn1(msg.certificates[i]));
+      }
+
+      var crls = [];
+      // TODO: implement CRLs
+
+      // [0] SignedData
+      var signedData = asn1.create(asn1.Class.CONTEXT_SPECIFIC, 0, true, [
+        asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+          // Version
+          asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
+            asn1.integerToDer(msg.version).getBytes()),
+          // DigestAlgorithmIdentifiers
+          asn1.create(
+            asn1.Class.UNIVERSAL, asn1.Type.SET, true,
+            msg.digestAlgorithmIdentifiers),
+          // ContentInfo
+          msg.contentInfo
+        ])
+      ]);
+      if(certs.length > 0) {
+        // [0] IMPLICIT ExtendedCertificatesAndCertificates OPTIONAL
+        signedData.value[0].value.push(
+          asn1.create(asn1.Class.CONTEXT_SPECIFIC, 0, true, certs));
+      }
+      if(crls.length > 0) {
+        // [1] IMPLICIT CertificateRevocationLists OPTIONAL
+        signedData.value[0].value.push(
+          asn1.create(asn1.Class.CONTEXT_SPECIFIC, 1, true, crls));
+      }
+      // SignerInfos
+      signedData.value[0].value.push(
+        asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SET, true,
+          msg.signerInfos));
+
+      // ContentInfo
+      return asn1.create(
+        asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+          // ContentType
+          asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+            asn1.oidToDer(msg.type).getBytes()),
+          // [0] SignedData
+          signedData
+        ]);
+    },
+
+    /**
+     * Add (another) entity to list of signers.
+     *
+     * Note: If authenticatedAttributes are provided, then, per RFC 2315,
+     * they must include at least two attributes: content type and
+     * message digest. The message digest attribute value will be
+     * auto-calculated during signing and will be ignored if provided.
+     *
+     * Here's an example of providing these two attributes:
+     *
+     * forge.pkcs7.createSignedData();
+     * p7.addSigner({
+     *   issuer: cert.issuer.attributes,
+     *   serialNumber: cert.serialNumber,
+     *   key: privateKey,
+     *   digestAlgorithm: forge.pki.oids.sha1,
+     *   authenticatedAttributes: [{
+     *     type: forge.pki.oids.contentType,
+     *     value: forge.pki.oids.data
+     *   }, {
+     *     type: forge.pki.oids.messageDigest
+     *   }]
+     * });
+     *
+     * TODO: Support [subjectKeyIdentifier] as signer's ID.
+     *
+     * @param signer the signer information:
+     *          key the signer's private key.
+     *          [certificate] a certificate containing the public key
+     *            associated with the signer's private key; use this option as
+     *            an alternative to specifying signer.issuer and
+     *            signer.serialNumber.
+     *          [issuer] the issuer attributes (eg: cert.issuer.attributes).
+     *          [serialNumber] the signer's certificate's serial number in
+     *           hexadecimal (eg: cert.serialNumber).
+     *          [digestAlgorithm] the message digest OID, as a string, to use
+     *            (eg: forge.pki.oids.sha1).
+     *          [authenticatedAttributes] an optional array of attributes
+     *            to also sign along with the content.
+     */
+    addSigner: function(signer) {
+      var issuer = signer.issuer;
+      var serialNumber = signer.serialNumber;
+      if(signer.certificate) {
+        var cert = signer.certificate;
+        if(typeof cert === 'string') {
+          cert = forge.pki.certificateFromPem(cert);
+        }
+        issuer = cert.issuer.attributes;
+        serialNumber = cert.serialNumber;
+      }
+      var key = signer.key;
+      if(!key) {
+        throw new Error(
+          'Could not add PKCS#7 signer; no private key specified.');
+      }
+      if(typeof key === 'string') {
+        key = forge.pki.privateKeyFromPem(key);
+      }
+
+      // ensure OID known for digest algorithm
+      var digestAlgorithm = signer.digestAlgorithm || forge.pki.oids.sha1;
+      switch(digestAlgorithm) {
+      case forge.pki.oids.sha1:
+      case forge.pki.oids.sha256:
+      case forge.pki.oids.sha384:
+      case forge.pki.oids.sha512:
+      case forge.pki.oids.md5:
+        break;
+      default:
+        throw new Error(
+          'Could not add PKCS#7 signer; unknown message digest algorithm: ' +
+          digestAlgorithm);
+      }
+
+      // if authenticatedAttributes is present, then the attributes
+      // must contain at least PKCS #9 content-type and message-digest
+      var authenticatedAttributes = signer.authenticatedAttributes || [];
+      if(authenticatedAttributes.length > 0) {
+        var contentType = false;
+        var messageDigest = false;
+        for(var i = 0; i < authenticatedAttributes.length; ++i) {
+          var attr = authenticatedAttributes[i];
+          if(!contentType && attr.type === forge.pki.oids.contentType) {
+            contentType = true;
+            if(messageDigest) {
+              break;
+            }
+            continue;
+          }
+          if(!messageDigest && attr.type === forge.pki.oids.messageDigest) {
+            messageDigest = true;
+            if(contentType) {
+              break;
+            }
+            continue;
+          }
+        }
+
+        if(!contentType || !messageDigest) {
+          throw new Error('Invalid signer.authenticatedAttributes. If ' +
+            'signer.authenticatedAttributes is specified, then it must ' +
+            'contain at least two attributes, PKCS #9 content-type and ' +
+            'PKCS #9 message-digest.');
+        }
+      }
+
+      msg.signers.push({
+        key: key,
+        version: 1,
+        issuer: issuer,
+        serialNumber: serialNumber,
+        digestAlgorithm: digestAlgorithm,
+        signatureAlgorithm: forge.pki.oids.rsaEncryption,
+        signature: null,
+        authenticatedAttributes: authenticatedAttributes,
+        unauthenticatedAttributes: []
+      });
+    },
+
+    /**
+     * Signs the content.
+     * @param options Options to apply when signing:
+     *    [detached] boolean. If signing should be done in detached mode. Defaults to false.
+     */
+    sign: function(options) {
+      options = options || {};
+      // auto-generate content info
+      if(typeof msg.content !== 'object' || msg.contentInfo === null) {
+        // use Data ContentInfo
+        msg.contentInfo = asn1.create(
+          asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+            // ContentType
+            asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+              asn1.oidToDer(forge.pki.oids.data).getBytes())
+          ]);
+
+        // add actual content, if present
+        if('content' in msg) {
+          var content;
+          if(msg.content instanceof forge.util.ByteBuffer) {
+            content = msg.content.bytes();
+          } else if(typeof msg.content === 'string') {
+            content = forge.util.encodeUtf8(msg.content);
+          }
+
+          if (options.detached) {
+            msg.detachedContent = asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OCTETSTRING, false, content);
+          } else {
+            msg.contentInfo.value.push(
+              // [0] EXPLICIT content
+              asn1.create(asn1.Class.CONTEXT_SPECIFIC, 0, true, [
+                asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OCTETSTRING, false,
+                  content)
+              ]));
+          }
+        }
+      }
+
+      // no signers, return early (degenerate case for certificate container)
+      if(msg.signers.length === 0) {
+        return;
+      }
+
+      // generate digest algorithm identifiers
+      var mds = addDigestAlgorithmIds();
+
+      // generate signerInfos
+      addSignerInfos(mds);
+    },
+
+    verify: function() {
+      throw new Error('PKCS#7 signature verification not yet implemented.');
+    },
+
+    /**
+     * Add a certificate.
+     *
+     * @param cert the certificate to add.
+     */
+    addCertificate: function(cert) {
+      // convert from PEM
+      if(typeof cert === 'string') {
+        cert = forge.pki.certificateFromPem(cert);
+      }
+      msg.certificates.push(cert);
+    },
+
+    /**
+     * Add a certificate revokation list.
+     *
+     * @param crl the certificate revokation list to add.
+     */
+    addCertificateRevokationList: function(crl) {
+      throw new Error('PKCS#7 CRL support not yet implemented.');
+    }
+  };
+  return msg;
+
+  function addDigestAlgorithmIds() {
+    var mds = {};
+
+    for(var i = 0; i < msg.signers.length; ++i) {
+      var signer = msg.signers[i];
+      var oid = signer.digestAlgorithm;
+      if(!(oid in mds)) {
+        // content digest
+        mds[oid] = forge.md[forge.pki.oids[oid]].create();
+      }
+      if(signer.authenticatedAttributes.length === 0) {
+        // no custom attributes to digest; use content message digest
+        signer.md = mds[oid];
+      } else {
+        // custom attributes to be digested; use own message digest
+        // TODO: optimize to just copy message digest state if that
+        // feature is ever supported with message digests
+        signer.md = forge.md[forge.pki.oids[oid]].create();
+      }
+    }
+
+    // add unique digest algorithm identifiers
+    msg.digestAlgorithmIdentifiers = [];
+    for(var oid in mds) {
+      msg.digestAlgorithmIdentifiers.push(
+        // AlgorithmIdentifier
+        asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+          // algorithm
+          asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+            asn1.oidToDer(oid).getBytes()),
+          // parameters (null)
+          asn1.create(asn1.Class.UNIVERSAL, asn1.Type.NULL, false, '')
+        ]));
+    }
+
+    return mds;
+  }
+
+  function addSignerInfos(mds) {
+    var content;
+
+    if (msg.detachedContent) {
+      // Signature has been made in detached mode.
+      content = msg.detachedContent;
+    } else {
+      // Note: ContentInfo is a SEQUENCE with 2 values, second value is
+      // the content field and is optional for a ContentInfo but required here
+      // since signers are present
+      // get ContentInfo content
+      content = msg.contentInfo.value[1];
+      // skip [0] EXPLICIT content wrapper
+      content = content.value[0];
+    }
+
+    if(!content) {
+      throw new Error(
+        'Could not sign PKCS#7 message; there is no content to sign.');
+    }
+
+    // get ContentInfo content type
+    var contentType = asn1.derToOid(msg.contentInfo.value[0].value);
+
+    // serialize content
+    var bytes = asn1.toDer(content);
+
+    // skip identifier and length per RFC 2315 9.3
+    // skip identifier (1 byte)
+    bytes.getByte();
+    // read and discard length bytes
+    asn1.getBerValueLength(bytes);
+    bytes = bytes.getBytes();
+
+    // digest content DER value bytes
+    for(var oid in mds) {
+      mds[oid].start().update(bytes);
+    }
+
+    // sign content
+    var signingTime = new Date();
+    for(var i = 0; i < msg.signers.length; ++i) {
+      var signer = msg.signers[i];
+
+      if(signer.authenticatedAttributes.length === 0) {
+        // if ContentInfo content type is not "Data", then
+        // authenticatedAttributes must be present per RFC 2315
+        if(contentType !== forge.pki.oids.data) {
+          throw new Error(
+            'Invalid signer; authenticatedAttributes must be present ' +
+            'when the ContentInfo content type is not PKCS#7 Data.');
+        }
+      } else {
+        // process authenticated attributes
+        // [0] IMPLICIT
+        signer.authenticatedAttributesAsn1 = asn1.create(
+          asn1.Class.CONTEXT_SPECIFIC, 0, true, []);
+
+        // per RFC 2315, attributes are to be digested using a SET container
+        // not the above [0] IMPLICIT container
+        var attrsAsn1 = asn1.create(
+          asn1.Class.UNIVERSAL, asn1.Type.SET, true, []);
+
+        for(var ai = 0; ai < signer.authenticatedAttributes.length; ++ai) {
+          var attr = signer.authenticatedAttributes[ai];
+          if(attr.type === forge.pki.oids.messageDigest) {
+            // use content message digest as value
+            attr.value = mds[signer.digestAlgorithm].digest();
+          } else if(attr.type === forge.pki.oids.signingTime) {
+            // auto-populate signing time if not already set
+            if(!attr.value) {
+              attr.value = signingTime;
+            }
+          }
+
+          // convert to ASN.1 and push onto Attributes SET (for signing) and
+          // onto authenticatedAttributesAsn1 to complete SignedData ASN.1
+          // TODO: optimize away duplication
+          attrsAsn1.value.push(_attributeToAsn1(attr));
+          signer.authenticatedAttributesAsn1.value.push(_attributeToAsn1(attr));
+        }
+
+        // DER-serialize and digest SET OF attributes only
+        bytes = asn1.toDer(attrsAsn1).getBytes();
+        signer.md.start().update(bytes);
+      }
+
+      // sign digest
+      signer.signature = signer.key.sign(signer.md, 'RSASSA-PKCS1-V1_5');
+    }
+
+    // add signer info
+    msg.signerInfos = _signersToAsn1(msg.signers);
+  }
+};
+
+/**
+ * Creates an empty PKCS#7 message of type EncryptedData.
+ *
+ * @return the message.
+ */
+p7.createEncryptedData = function() {
+  var msg = null;
+  msg = {
+    type: forge.pki.oids.encryptedData,
+    version: 0,
+    encryptedContent: {
+      algorithm: forge.pki.oids['aes256-CBC']
+    },
+
+    /**
+     * Reads an EncryptedData content block (in ASN.1 format)
+     *
+     * @param obj The ASN.1 representation of the EncryptedData content block
+     */
+    fromAsn1: function(obj) {
+      // Validate EncryptedData content block and capture data.
+      _fromAsn1(msg, obj, p7.asn1.encryptedDataValidator);
+    },
+
+    /**
+     * Decrypt encrypted content
+     *
+     * @param key The (symmetric) key as a byte buffer
+     */
+    decrypt: function(key) {
+      if(key !== undefined) {
+        msg.encryptedContent.key = key;
+      }
+      _decryptContent(msg);
+    }
+  };
+  return msg;
+};
+
+/**
+ * Creates an empty PKCS#7 message of type EnvelopedData.
+ *
+ * @return the message.
+ */
+p7.createEnvelopedData = function() {
+  var msg = null;
+  msg = {
+    type: forge.pki.oids.envelopedData,
+    version: 0,
+    recipients: [],
+    encryptedContent: {
+      algorithm: forge.pki.oids['aes256-CBC']
+    },
+
+    /**
+     * Reads an EnvelopedData content block (in ASN.1 format)
+     *
+     * @param obj the ASN.1 representation of the EnvelopedData content block.
+     */
+    fromAsn1: function(obj) {
+      // validate EnvelopedData content block and capture data
+      var capture = _fromAsn1(msg, obj, p7.asn1.envelopedDataValidator);
+      msg.recipients = _recipientsFromAsn1(capture.recipientInfos.value);
+    },
+
+    toAsn1: function() {
+      // ContentInfo
+      return asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+        // ContentType
+        asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+          asn1.oidToDer(msg.type).getBytes()),
+        // [0] EnvelopedData
+        asn1.create(asn1.Class.CONTEXT_SPECIFIC, 0, true, [
+          asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+            // Version
+            asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
+              asn1.integerToDer(msg.version).getBytes()),
+            // RecipientInfos
+            asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SET, true,
+              _recipientsToAsn1(msg.recipients)),
+            // EncryptedContentInfo
+            asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true,
+              _encryptedContentToAsn1(msg.encryptedContent))
+          ])
+        ])
+      ]);
+    },
+
+    /**
+     * Find recipient by X.509 certificate's issuer.
+     *
+     * @param cert the certificate with the issuer to look for.
+     *
+     * @return the recipient object.
+     */
+    findRecipient: function(cert) {
+      var sAttr = cert.issuer.attributes;
+
+      for(var i = 0; i < msg.recipients.length; ++i) {
+        var r = msg.recipients[i];
+        var rAttr = r.issuer;
+
+        if(r.serialNumber !== cert.serialNumber) {
+          continue;
+        }
+
+        if(rAttr.length !== sAttr.length) {
+          continue;
+        }
+
+        var match = true;
+        for(var j = 0; j < sAttr.length; ++j) {
+          if(rAttr[j].type !== sAttr[j].type ||
+            rAttr[j].value !== sAttr[j].value) {
+            match = false;
+            break;
+          }
+        }
+
+        if(match) {
+          return r;
+        }
+      }
+
+      return null;
+    },
+
+    /**
+     * Decrypt enveloped content
+     *
+     * @param recipient The recipient object related to the private key
+     * @param privKey The (RSA) private key object
+     */
+    decrypt: function(recipient, privKey) {
+      if(msg.encryptedContent.key === undefined && recipient !== undefined &&
+        privKey !== undefined) {
+        switch(recipient.encryptedContent.algorithm) {
+          case forge.pki.oids.rsaEncryption:
+          case forge.pki.oids.desCBC:
+            var key = privKey.decrypt(recipient.encryptedContent.content);
+            msg.encryptedContent.key = forge.util.createBuffer(key);
+            break;
+
+          default:
+            throw new Error('Unsupported asymmetric cipher, ' +
+              'OID ' + recipient.encryptedContent.algorithm);
+        }
+      }
+
+      _decryptContent(msg);
+    },
+
+    /**
+     * Add (another) entity to list of recipients.
+     *
+     * @param cert The certificate of the entity to add.
+     */
+    addRecipient: function(cert) {
+      msg.recipients.push({
+        version: 0,
+        issuer: cert.issuer.attributes,
+        serialNumber: cert.serialNumber,
+        encryptedContent: {
+          // We simply assume rsaEncryption here, since forge.pki only
+          // supports RSA so far.  If the PKI module supports other
+          // ciphers one day, we need to modify this one as well.
+          algorithm: forge.pki.oids.rsaEncryption,
+          key: cert.publicKey
+        }
+      });
+    },
+
+    /**
+     * Encrypt enveloped content.
+     *
+     * This function supports two optional arguments, cipher and key, which
+     * can be used to influence symmetric encryption.  Unless cipher is
+     * provided, the cipher specified in encryptedContent.algorithm is used
+     * (defaults to AES-256-CBC).  If no key is provided, encryptedContent.key
+     * is (re-)used.  If that one's not set, a random key will be generated
+     * automatically.
+     *
+     * @param [key] The key to be used for symmetric encryption.
+     * @param [cipher] The OID of the symmetric cipher to use.
+     */
+    encrypt: function(key, cipher) {
+      // Part 1: Symmetric encryption
+      if(msg.encryptedContent.content === undefined) {
+        cipher = cipher || msg.encryptedContent.algorithm;
+        key = key || msg.encryptedContent.key;
+
+        var keyLen, ivLen, ciphFn;
+        switch(cipher) {
+          case forge.pki.oids['aes128-CBC']:
+            keyLen = 16;
+            ivLen = 16;
+            ciphFn = forge.aes.createEncryptionCipher;
+            break;
+
+          case forge.pki.oids['aes192-CBC']:
+            keyLen = 24;
+            ivLen = 16;
+            ciphFn = forge.aes.createEncryptionCipher;
+            break;
+
+          case forge.pki.oids['aes256-CBC']:
+            keyLen = 32;
+            ivLen = 16;
+            ciphFn = forge.aes.createEncryptionCipher;
+            break;
+
+          case forge.pki.oids['des-EDE3-CBC']:
+            keyLen = 24;
+            ivLen = 8;
+            ciphFn = forge.des.createEncryptionCipher;
+            break;
+
+          default:
+            throw new Error('Unsupported symmetric cipher, OID ' + cipher);
+        }
+
+        if(key === undefined) {
+          key = forge.util.createBuffer(forge.random.getBytes(keyLen));
+        } else if(key.length() != keyLen) {
+          throw new Error('Symmetric key has wrong length; ' +
+            'got ' + key.length() + ' bytes, expected ' + keyLen + '.');
+        }
+
+        // Keep a copy of the key & IV in the object, so the caller can
+        // use it for whatever reason.
+        msg.encryptedContent.algorithm = cipher;
+        msg.encryptedContent.key = key;
+        msg.encryptedContent.parameter = forge.util.createBuffer(
+          forge.random.getBytes(ivLen));
+
+        var ciph = ciphFn(key);
+        ciph.start(msg.encryptedContent.parameter.copy());
+        ciph.update(msg.content);
+
+        // The finish function does PKCS#7 padding by default, therefore
+        // no action required by us.
+        if(!ciph.finish()) {
+          throw new Error('Symmetric encryption failed.');
+        }
+
+        msg.encryptedContent.content = ciph.output;
+      }
+
+      // Part 2: asymmetric encryption for each recipient
+      for(var i = 0; i < msg.recipients.length; ++i) {
+        var recipient = msg.recipients[i];
+
+        // Nothing to do, encryption already done.
+        if(recipient.encryptedContent.content !== undefined) {
+          continue;
+        }
+
+        switch(recipient.encryptedContent.algorithm) {
+          case forge.pki.oids.rsaEncryption:
+            recipient.encryptedContent.content =
+              recipient.encryptedContent.key.encrypt(
+                msg.encryptedContent.key.data);
+            break;
+
+          default:
+            throw new Error('Unsupported asymmetric cipher, OID ' +
+              recipient.encryptedContent.algorithm);
+        }
+      }
+    }
+  };
+  return msg;
+};
+
+/**
+ * Converts a single recipient from an ASN.1 object.
+ *
+ * @param obj the ASN.1 RecipientInfo.
+ *
+ * @return the recipient object.
+ */
+function _recipientFromAsn1(obj) {
+  // validate EnvelopedData content block and capture data
+  var capture = {};
+  var errors = [];
+  if(!asn1.validate(obj, p7.asn1.recipientInfoValidator, capture, errors)) {
+    var error = new Error('Cannot read PKCS#7 RecipientInfo. ' +
+      'ASN.1 object is not an PKCS#7 RecipientInfo.');
+    error.errors = errors;
+    throw error;
+  }
+
+  return {
+    version: capture.version.charCodeAt(0),
+    issuer: forge.pki.RDNAttributesAsArray(capture.issuer),
+    serialNumber: forge.util.createBuffer(capture.serial).toHex(),
+    encryptedContent: {
+      algorithm: asn1.derToOid(capture.encAlgorithm),
+      parameter: capture.encParameter ? capture.encParameter.value : undefined,
+      content: capture.encKey
+    }
+  };
+}
+
+/**
+ * Converts a single recipient object to an ASN.1 object.
+ *
+ * @param obj the recipient object.
+ *
+ * @return the ASN.1 RecipientInfo.
+ */
+function _recipientToAsn1(obj) {
+  return asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+    // Version
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
+      asn1.integerToDer(obj.version).getBytes()),
+    // IssuerAndSerialNumber
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+      // Name
+      forge.pki.distinguishedNameToAsn1({attributes: obj.issuer}),
+      // Serial
+      asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
+        forge.util.hexToBytes(obj.serialNumber))
+    ]),
+    // KeyEncryptionAlgorithmIdentifier
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+      // Algorithm
+      asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+        asn1.oidToDer(obj.encryptedContent.algorithm).getBytes()),
+      // Parameter, force NULL, only RSA supported for now.
+      asn1.create(asn1.Class.UNIVERSAL, asn1.Type.NULL, false, '')
+    ]),
+    // EncryptedKey
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OCTETSTRING, false,
+      obj.encryptedContent.content)
+  ]);
+}
+
+/**
+ * Map a set of RecipientInfo ASN.1 objects to recipient objects.
+ *
+ * @param infos an array of ASN.1 representations RecipientInfo (i.e. SET OF).
+ *
+ * @return an array of recipient objects.
+ */
+function _recipientsFromAsn1(infos) {
+  var ret = [];
+  for(var i = 0; i < infos.length; ++i) {
+    ret.push(_recipientFromAsn1(infos[i]));
+  }
+  return ret;
+}
+
+/**
+ * Map an array of recipient objects to ASN.1 RecipientInfo objects.
+ *
+ * @param recipients an array of recipientInfo objects.
+ *
+ * @return an array of ASN.1 RecipientInfos.
+ */
+function _recipientsToAsn1(recipients) {
+  var ret = [];
+  for(var i = 0; i < recipients.length; ++i) {
+    ret.push(_recipientToAsn1(recipients[i]));
+  }
+  return ret;
+}
+
+/**
+ * Converts a single signer from an ASN.1 object.
+ *
+ * @param obj the ASN.1 representation of a SignerInfo.
+ *
+ * @return the signer object.
+ */
+function _signerFromAsn1(obj) {
+  // validate EnvelopedData content block and capture data
+  var capture = {};
+  var errors = [];
+  if(!asn1.validate(obj, p7.asn1.signerInfoValidator, capture, errors)) {
+    var error = new Error('Cannot read PKCS#7 SignerInfo. ' +
+      'ASN.1 object is not an PKCS#7 SignerInfo.');
+    error.errors = errors;
+    throw error;
+  }
+
+  var rval = {
+    version: capture.version.charCodeAt(0),
+    issuer: forge.pki.RDNAttributesAsArray(capture.issuer),
+    serialNumber: forge.util.createBuffer(capture.serial).toHex(),
+    digestAlgorithm: asn1.derToOid(capture.digestAlgorithm),
+    signatureAlgorithm: asn1.derToOid(capture.signatureAlgorithm),
+    signature: capture.signature,
+    authenticatedAttributes: [],
+    unauthenticatedAttributes: []
+  };
+
+  // TODO: convert attributes
+  var authenticatedAttributes = capture.authenticatedAttributes || [];
+  var unauthenticatedAttributes = capture.unauthenticatedAttributes || [];
+
+  return rval;
+}
+
+/**
+ * Converts a single signerInfo object to an ASN.1 object.
+ *
+ * @param obj the signerInfo object.
+ *
+ * @return the ASN.1 representation of a SignerInfo.
+ */
+function _signerToAsn1(obj) {
+  // SignerInfo
+  var rval = asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+    // version
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
+      asn1.integerToDer(obj.version).getBytes()),
+    // issuerAndSerialNumber
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+      // name
+      forge.pki.distinguishedNameToAsn1({attributes: obj.issuer}),
+      // serial
+      asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
+        forge.util.hexToBytes(obj.serialNumber))
+    ]),
+    // digestAlgorithm
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+      // algorithm
+      asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+        asn1.oidToDer(obj.digestAlgorithm).getBytes()),
+      // parameters (null)
+      asn1.create(asn1.Class.UNIVERSAL, asn1.Type.NULL, false, '')
+    ])
+  ]);
+
+  // authenticatedAttributes (OPTIONAL)
+  if(obj.authenticatedAttributesAsn1) {
+    // add ASN.1 previously generated during signing
+    rval.value.push(obj.authenticatedAttributesAsn1);
+  }
+
+  // digestEncryptionAlgorithm
+  rval.value.push(asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+    // algorithm
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+      asn1.oidToDer(obj.signatureAlgorithm).getBytes()),
+    // parameters (null)
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.NULL, false, '')
+  ]));
+
+  // encryptedDigest
+  rval.value.push(asn1.create(
+    asn1.Class.UNIVERSAL, asn1.Type.OCTETSTRING, false, obj.signature));
+
+  // unauthenticatedAttributes (OPTIONAL)
+  if(obj.unauthenticatedAttributes.length > 0) {
+    // [1] IMPLICIT
+    var attrsAsn1 = asn1.create(asn1.Class.CONTEXT_SPECIFIC, 1, true, []);
+    for(var i = 0; i < obj.unauthenticatedAttributes.length; ++i) {
+      var attr = obj.unauthenticatedAttributes[i];
+      attrsAsn1.values.push(_attributeToAsn1(attr));
+    }
+    rval.value.push(attrsAsn1);
+  }
+
+  return rval;
+}
+
+/**
+ * Map a set of SignerInfo ASN.1 objects to an array of signer objects.
+ *
+ * @param signerInfoAsn1s an array of ASN.1 SignerInfos (i.e. SET OF).
+ *
+ * @return an array of signers objects.
+ */
+function _signersFromAsn1(signerInfoAsn1s) {
+  var ret = [];
+  for(var i = 0; i < signerInfoAsn1s.length; ++i) {
+    ret.push(_signerFromAsn1(signerInfoAsn1s[i]));
+  }
+  return ret;
+}
+
+/**
+ * Map an array of signer objects to ASN.1 objects.
+ *
+ * @param signers an array of signer objects.
+ *
+ * @return an array of ASN.1 SignerInfos.
+ */
+function _signersToAsn1(signers) {
+  var ret = [];
+  for(var i = 0; i < signers.length; ++i) {
+    ret.push(_signerToAsn1(signers[i]));
+  }
+  return ret;
+}
+
+/**
+ * Convert an attribute object to an ASN.1 Attribute.
+ *
+ * @param attr the attribute object.
+ *
+ * @return the ASN.1 Attribute.
+ */
+function _attributeToAsn1(attr) {
+  var value;
+
+  // TODO: generalize to support more attributes
+  if(attr.type === forge.pki.oids.contentType) {
+    value = asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+      asn1.oidToDer(attr.value).getBytes());
+  } else if(attr.type === forge.pki.oids.messageDigest) {
+    value = asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OCTETSTRING, false,
+      attr.value.bytes());
+  } else if(attr.type === forge.pki.oids.signingTime) {
+    /* Note per RFC 2985: Dates between 1 January 1950 and 31 December 2049
+      (inclusive) MUST be encoded as UTCTime. Any dates with year values
+      before 1950 or after 2049 MUST be encoded as GeneralizedTime. [Further,]
+      UTCTime values MUST be expressed in Greenwich Mean Time (Zulu) and MUST
+      include seconds (i.e., times are YYMMDDHHMMSSZ), even where the
+      number of seconds is zero.  Midnight (GMT) must be represented as
+      "YYMMDD000000Z". */
+    // TODO: make these module-level constants
+    var jan_1_1950 = new Date('1950-01-01T00:00:00Z');
+    var jan_1_2050 = new Date('2050-01-01T00:00:00Z');
+    var date = attr.value;
+    if(typeof date === 'string') {
+      // try to parse date
+      var timestamp = Date.parse(date);
+      if(!isNaN(timestamp)) {
+        date = new Date(timestamp);
+      } else if(date.length === 13) {
+        // YYMMDDHHMMSSZ (13 chars for UTCTime)
+        date = asn1.utcTimeToDate(date);
+      } else {
+        // assume generalized time
+        date = asn1.generalizedTimeToDate(date);
+      }
+    }
+
+    if(date >= jan_1_1950 && date < jan_1_2050) {
+      value = asn1.create(
+        asn1.Class.UNIVERSAL, asn1.Type.UTCTIME, false,
+        asn1.dateToUtcTime(date));
+    } else {
+      value = asn1.create(
+        asn1.Class.UNIVERSAL, asn1.Type.GENERALIZEDTIME, false,
+        asn1.dateToGeneralizedTime(date));
+    }
+  }
+
+  // TODO: expose as common API call
+  // create a RelativeDistinguishedName set
+  // each value in the set is an AttributeTypeAndValue first
+  // containing the type (an OID) and second the value
+  return asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+    // AttributeType
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+      asn1.oidToDer(attr.type).getBytes()),
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SET, true, [
+      // AttributeValue
+      value
+    ])
+  ]);
+}
+
+/**
+ * Map messages encrypted content to ASN.1 objects.
+ *
+ * @param ec The encryptedContent object of the message.
+ *
+ * @return ASN.1 representation of the encryptedContent object (SEQUENCE).
+ */
+function _encryptedContentToAsn1(ec) {
+  return [
+    // ContentType, always Data for the moment
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+      asn1.oidToDer(forge.pki.oids.data).getBytes()),
+    // ContentEncryptionAlgorithmIdentifier
+    asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
+      // Algorithm
+      asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
+        asn1.oidToDer(ec.algorithm).getBytes()),
+      // Parameters (IV)
+      !ec.parameter ?
+        undefined :
+        asn1.create(
+          asn1.Class.UNIVERSAL, asn1.Type.OCTETSTRING, false,
+          ec.parameter.getBytes())
+    ]),
+    // [0] EncryptedContent
+    asn1.create(asn1.Class.CONTEXT_SPECIFIC, 0, true, [
+      asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OCTETSTRING, false,
+        ec.content.getBytes())
+    ])
+  ];
+}
+
+/**
+ * Reads the "common part" of an PKCS#7 content block (in ASN.1 format)
+ *
+ * This function reads the "common part" of the PKCS#7 content blocks
+ * EncryptedData and EnvelopedData, i.e. version number and symmetrically
+ * encrypted content block.
+ *
+ * The result of the ASN.1 validate and capture process is returned
+ * to allow the caller to extract further data, e.g. the list of recipients
+ * in case of a EnvelopedData object.
+ *
+ * @param msg the PKCS#7 object to read the data to.
+ * @param obj the ASN.1 representation of the content block.
+ * @param validator the ASN.1 structure validator object to use.
+ *
+ * @return the value map captured by validator object.
+ */
+function _fromAsn1(msg, obj, validator) {
+  var capture = {};
+  var errors = [];
+  if(!asn1.validate(obj, validator, capture, errors)) {
+    var error = new Error('Cannot read PKCS#7 message. ' +
+      'ASN.1 object is not a supported PKCS#7 message.');
+    error.errors = error;
+    throw error;
+  }
+
+  // Check contentType, so far we only support (raw) Data.
+  var contentType = asn1.derToOid(capture.contentType);
+  if(contentType !== forge.pki.oids.data) {
+    throw new Error('Unsupported PKCS#7 message. ' +
+      'Only wrapped ContentType Data supported.');
+  }
+
+  if(capture.encryptedContent) {
+    var content = '';
+    if(forge.util.isArray(capture.encryptedContent)) {
+      for(var i = 0; i < capture.encryptedContent.length; ++i) {
+        if(capture.encryptedContent[i].type !== asn1.Type.OCTETSTRING) {
+          throw new Error('Malformed PKCS#7 message, expecting encrypted ' +
+            'content constructed of only OCTET STRING objects.');
+        }
+        content += capture.encryptedContent[i].value;
+      }
+    } else {
+      content = capture.encryptedContent;
+    }
+    msg.encryptedContent = {
+      algorithm: asn1.derToOid(capture.encAlgorithm),
+      parameter: forge.util.createBuffer(capture.encParameter.value),
+      content: forge.util.createBuffer(content)
+    };
+  }
+
+  if(capture.content) {
+    var content = '';
+    if(forge.util.isArray(capture.content)) {
+      for(var i = 0; i < capture.content.length; ++i) {
+        if(capture.content[i].type !== asn1.Type.OCTETSTRING) {
+          throw new Error('Malformed PKCS#7 message, expecting ' +
+            'content constructed of only OCTET STRING objects.');
+        }
+        content += capture.content[i].value;
+      }
+    } else {
+      content = capture.content;
+    }
+    msg.content = forge.util.createBuffer(content);
+  }
+
+  msg.version = capture.version.charCodeAt(0);
+  msg.rawCapture = capture;
+
+  return capture;
+}
+
+/**
+ * Decrypt the symmetrically encrypted content block of the PKCS#7 message.
+ *
+ * Decryption is skipped in case the PKCS#7 message object already has a
+ * (decrypted) content attribute.  The algorithm, key and cipher parameters
+ * (probably the iv) are taken from the encryptedContent attribute of the
+ * message object.
+ *
+ * @param The PKCS#7 message object.
+ */
+function _decryptContent(msg) {
+  if(msg.encryptedContent.key === undefined) {
+    throw new Error('Symmetric key not available.');
+  }
+
+  if(msg.content === undefined) {
+    var ciph;
+
+    switch(msg.encryptedContent.algorithm) {
+      case forge.pki.oids['aes128-CBC']:
+      case forge.pki.oids['aes192-CBC']:
+      case forge.pki.oids['aes256-CBC']:
+        ciph = forge.aes.createDecryptionCipher(msg.encryptedContent.key);
+        break;
+
+      case forge.pki.oids['desCBC']:
+      case forge.pki.oids['des-EDE3-CBC']:
+        ciph = forge.des.createDecryptionCipher(msg.encryptedContent.key);
+        break;
+
+      default:
+        throw new Error('Unsupported symmetric cipher, OID ' +
+          msg.encryptedContent.algorithm);
+    }
+    ciph.start(msg.encryptedContent.parameter);
+    ciph.update(msg.encryptedContent.content);
+
+    if(!ciph.finish()) {
+      throw new Error('Symmetric decryption failed.');
+    }
+
+    msg.content = ciph.output;
+  }
+}