const NS = 'http://salmon-protocol.org/ns/magic-env';
+ protected $actor = null; // Profile of user who has signed the envelope
+
protected $data = null; // When stored here it is _always_ base64url encoded
protected $data_type = null;
protected $encoding = null;
* @fixme may give fatal errors if some elements are missing or invalid XML
* @fixme calling DOMDocument::loadXML statically triggers warnings in strict mode
*/
- public function __construct($xml=null) {
+ public function __construct($xml=null, Profile $actor=null) {
if (!empty($xml)) {
- $dom = DOMDocument::loadXML($xml);
- if (!$dom instanceof DOMDocument) {
+ $dom = new DOMDocument();
+ if (!$dom->loadXML($xml)) {
throw new ServerException('Tried to load malformed XML as DOM');
} elseif (!$this->fromDom($dom)) {
throw new ServerException('Could not load MagicEnvelope from DOM');
}
+ } elseif ($actor instanceof Profile) {
+ // So far we only allow setting with _either_ $xml _or_ $actor as that's
+ // all our circumstances require. But it may be confusing for new developers.
+ // The idea is that feeding XML must be followed by interpretation and then
+ // running $magic_env->verify($profile), just as in SalmonAction->prepare(...)
+ // and supplying an $actor (which right now has to be a User) will require
+ // defining the $data, $data_type etc. attributes manually afterwards before
+ // signing the envelope..
+ $this->setActor($actor);
+ }
+ }
+
+ /**
+ * Retrieve Salmon keypair first by checking local database, but
+ * if it's not found, attempt discovery if it has been requested.
+ *
+ * @param Profile $profile The profile we're looking up keys for.
+ * @param boolean $discovery Network discovery if no local cache?
+ */
+ public function getKeyPair(Profile $profile, $discovery=false) {
+ if (!$profile->isLocal()) common_debug('Getting magic-public-key for non-local profile id=='.$profile->getID());
+ $magicsig = Magicsig::getKV('user_id', $profile->getID());
+
+ if ($discovery && !$magicsig instanceof Magicsig) {
+ if (!$profile->isLocal()) common_debug('magic-public-key not found, will do discovery for profile id=='.$profile->getID());
+ // Throws exception on failure, but does not try to _load_ the keypair string.
+ $keypair = $this->discoverKeyPair($profile);
+
+ $magicsig = new Magicsig();
+ $magicsig->user_id = $profile->getID();
+ $magicsig->importKeys($keypair);
+ // save the public key for this profile in our database.
+ // TODO: If the profile generates a new key remotely, we must be able to replace
+ // this (of course after callback-verification).
+ $magicsig->insert();
+ } elseif (!$magicsig instanceof Magicsig) { // No discovery request, so we'll give up.
+ throw new ServerException(sprintf('No public key found for profile (id==%d)', $profile->id));
}
+
+ assert($magicsig->publicKey instanceof Crypt_RSA);
+
+ return $magicsig;
}
/**
- * Get the Salmon keypair from a URI, uses XRD Discovery etc.
+ * Get the Salmon keypair from a URI, uses XRD Discovery etc. Reasonably
+ * you'll only get the public key ;)
*
- * @return Magicsig with loaded keypair
+ * The string will (hopefully) be formatted as described in Magicsig specification:
+ * https://salmon-protocol.googlecode.com/svn/trunk/draft-panzer-magicsig-01.html#anchor13
+ *
+ * @return string formatted as Magicsig keypair
*/
- public function getKeyPair($signer_uri)
+ public function discoverKeyPair(Profile $profile)
{
+ $signer_uri = $profile->getUri();
+ if (empty($signer_uri)) {
+ throw new ServerException(sprintf('Profile missing URI (id==%d)', $profile->getID()));
+ }
+
$disco = new Discovery();
// Throws exception on lookup problems
- $xrd = $disco->lookup($signer_uri);
+ try {
+ $xrd = $disco->lookup($signer_uri);
+ } catch (Exception $e) {
+ // Diaspora seems to require us to request the acct: uri
+ $xrd = $disco->lookup($profile->getAcctUri());
+ }
- $link = $xrd->get(Magicsig::PUBLICKEYREL);
- if (is_null($link)) {
- // TRANS: Exception.
- throw new Exception(_m('Unable to locate signer public key.'));
+ common_debug('Will try to find magic-public-key from XRD of profile id=='.$profile->getID());
+ $pubkey = null;
+ if (Event::handle('MagicsigPublicKeyFromXRD', array($xrd, &$pubkey))) {
+ $link = $xrd->get(Magicsig::PUBLICKEYREL);
+ if (is_null($link)) {
+ // TRANS: Exception.
+ throw new Exception(_m('Unable to locate signer public key.'));
+ }
+ $pubkey = $link->href;
+ }
+ if (empty($pubkey)) {
+ throw new ServerException('Empty Magicsig public key. A bug?');
}
// We have a public key element, let's hope it has proper key data.
$keypair = false;
- $parts = explode(',', $link->href);
+ $parts = explode(',', $pubkey);
if (count($parts) == 2) {
$keypair = $parts[1];
} else {
// Backwards compatibility check for separator bug in 0.9.0
- $parts = explode(';', $link->href);
+ $parts = explode(';', $pubkey);
if (count($parts) == 2) {
$keypair = $parts[1];
}
throw new Exception(_m('Incorrectly formatted public key element.'));
}
- $magicsig = Magicsig::fromString($keypair);
- if (!$magicsig instanceof Magicsig) {
- common_debug('Salmon error: unable to parse keypair: '.var_export($keypair,true));
- // TRANS: Exception when public key was properly formatted but not parsable.
- throw new ServerException(_m('Retrieved Salmon keypair could not be parsed.'));
- }
-
- return $magicsig;
+ return $keypair;
}
/**
* @param <type> $text
* @param <type> $mimetype
* @param Magicsig $magicsig Magicsig with private key available.
+ *
* @return MagicEnvelope object with all properties set
+ *
+ * @throws Exception of various kinds on signing failure
*/
- public static function signMessage($text, $mimetype, Magicsig $magicsig)
+ public function signMessage($text, $mimetype)
{
- $magic_env = new MagicEnvelope();
+ if (!$this->actor instanceof Profile) {
+ throw new ServerException('No profile to sign message with is set.');
+ } elseif (!$this->actor->isLocal()) {
+ throw new ServerException('Cannot sign magic envelopes with remote users since we have no private key.');
+ }
+
+ // Find already stored key
+ $magicsig = Magicsig::getKV('user_id', $this->actor->getID());
+ if (!$magicsig instanceof Magicsig) {
+ // and if it doesn't exist, it is time to create one!
+ $magicsig = Magicsig::generate($this->actor->getUser());
+ }
+ assert($magicsig instanceof Magicsig);
+ assert($magicsig->privateKey instanceof Crypt_RSA);
// Prepare text and metadata for signing
- $magic_env->data = Magicsig::base64_url_encode($text);
- $magic_env->data_type = $mimetype;
- $magic_env->encoding = self::ENCODING;
- $magic_env->alg = $magicsig->getName();
- // Get the actual signature
- $magic_env->sig = $magicsig->sign($magic_env->signingText());
+ $this->data = Magicsig::base64_url_encode($text);
+ $this->data_type = $mimetype;
+ $this->encoding = self::ENCODING;
+ $this->alg = $magicsig->getName();
- return $magic_env;
+ // Get the actual signature
+ $this->sig = $magicsig->sign($this->signingText());
}
/**
*
* @return string representation of XML document
*/
- public function toXML() {
+ public function toXML(Profile $target=null, $flavour=null) {
$xs = new XMLStringer();
- $xs->startXML();
- $xs->elementStart('me:env', array('xmlns:me' => self::NS));
- $xs->element('me:data', array('type' => $this->data_type), $this->data);
- $xs->element('me:encoding', null, $this->encoding);
- $xs->element('me:alg', null, $this->alg);
- $xs->element('me:sig', null, $this->sig);
- $xs->elementEnd('me:env');
-
- $string = $xs->getString();
- common_debug('MagicEnvelope XML: ' . $string);
- return $string;
+ $xs->startXML(); // header, to point out it's not HTML or anything...
+ if (Event::handle('StartMagicEnvelopeToXML', array($this, $xs, $flavour, $target))) {
+ // fall back to our default, normal Magic Envelope XML.
+ // the $xs element _may_ have had elements added, or could get in the end event
+ $xs->elementStart('me:env', array('xmlns:me' => self::NS));
+ $xs->element('me:data', array('type' => $this->data_type), $this->data);
+ $xs->element('me:encoding', null, $this->encoding);
+ $xs->element('me:alg', null, $this->alg);
+ $xs->element('me:sig', null, $this->getSignature());
+ $xs->elementEnd('me:env');
+
+ Event::handle('EndMagicEnvelopeToXML', array($this, $xs, $flavour, $target));
+ }
+ return $xs->getString();
}
- /**
+ /*
* Extract the contained XML payload, and insert a copy of the envelope
* signature data as an <me:provenance> section.
*
- * @return string representation of modified XML document
+ * @return DOMDocument of Atom entry
*
* @fixme in case of XML parsing errors, this will spew to the error log or output
*/
- public function unfold()
+ public function getPayload()
{
$dom = new DOMDocument();
- $dom->loadXML(Magicsig::base64_url_decode($this->data));
+ if (!$dom->loadXML(Magicsig::base64_url_decode($this->data))) {
+ throw new ServerException('Malformed XML in Salmon payload');
+ }
- if ($dom->documentElement->tagName != 'entry') {
- return false;
+ switch ($this->data_type) {
+ case 'application/atom+xml':
+ if ($dom->documentElement->namespaceURI !== Activity::ATOM
+ || $dom->documentElement->tagName !== 'entry') {
+ throw new ServerException(_m('Salmon post must be an Atom entry.'));
+ }
+ $prov = $dom->createElementNS(self::NS, 'me:provenance');
+ $prov->setAttribute('xmlns:me', self::NS);
+ $data = $dom->createElementNS(self::NS, 'me:data', $this->data);
+ $data->setAttribute('type', $this->data_type);
+ $prov->appendChild($data);
+ $enc = $dom->createElementNS(self::NS, 'me:encoding', $this->encoding);
+ $prov->appendChild($enc);
+ $alg = $dom->createElementNS(self::NS, 'me:alg', $this->alg);
+ $prov->appendChild($alg);
+ $sig = $dom->createElementNS(self::NS, 'me:sig', $this->getSignature());
+ $prov->appendChild($sig);
+
+ $dom->documentElement->appendChild($prov);
+ break;
+ default:
+ throw new ServerException('Unknown Salmon payload data type');
+ }
+ return $dom;
+ }
+
+ public function getSignature()
+ {
+ if (empty($this->sig)) {
+ throw new ServerException('You must first call signMessage before getSignature');
}
+ return $this->sig;
+ }
- $prov = $dom->createElementNS(self::NS, 'me:provenance');
- $prov->setAttribute('xmlns:me', self::NS);
- $data = $dom->createElementNS(self::NS, 'me:data', $this->data);
- $data->setAttribute('type', $this->data_type);
- $prov->appendChild($data);
- $enc = $dom->createElementNS(self::NS, 'me:encoding', $this->encoding);
- $prov->appendChild($enc);
- $alg = $dom->createElementNS(self::NS, 'me:alg', $this->alg);
- $prov->appendChild($alg);
- $sig = $dom->createElementNS(self::NS, 'me:sig', $this->sig);
- $prov->appendChild($sig);
-
- $dom->documentElement->appendChild($prov);
-
- return $dom->saveXML();
+ public function getSignatureAlgorithm()
+ {
+ return $this->alg;
+ }
+
+ public function getData()
+ {
+ return $this->data;
+ }
+
+ public function getDataType()
+ {
+ return $this->data_type;
+ }
+
+ public function getEncoding()
+ {
+ return $this->encoding;
}
/**
- * Find the author URI referenced in the given Atom entry.
- *
- * @param string $text string containing Atom entry XML
- * @return mixed URI string or false if XML parsing fails, or null if no author URI can be found
+ * Find the author URI referenced in the payload Atom entry.
*
- * @fixme XML parsing failures will spew to error logs/output
+ * @return string URI for author
+ * @throws ServerException on failure
*/
- public function getAuthorUri($text) {
- $doc = new DOMDocument();
- if (!$doc->loadXML($text)) {
- return FALSE;
- }
-
- if ($doc->documentElement->tagName == 'entry') {
- $authors = $doc->documentElement->getElementsByTagName('author');
- foreach ($authors as $author) {
- $uris = $author->getElementsByTagName('uri');
- foreach ($uris as $uri) {
- return $uri->nodeValue;
- }
+ public function getAuthorUri() {
+ $doc = $this->getPayload();
+
+ $authors = $doc->documentElement->getElementsByTagName('author');
+ foreach ($authors as $author) {
+ $uris = $author->getElementsByTagName('uri');
+ foreach ($uris as $uri) {
+ return $uri->nodeValue;
}
}
+ throw new ServerException('No author URI found in Salmon payload data');
}
/**
*
* Details of failure conditions are dumped to output log and not exposed to caller.
*
+ * @param Profile $profile profile used to get locally cached public signature key
+ * or if necessary perform discovery on.
+ *
* @return boolean
*/
- public function verify()
+ public function verify(Profile $profile)
{
if ($this->alg != 'RSA-SHA256') {
- common_log(LOG_DEBUG, "Salmon error: bad algorithm");
+ common_debug("Salmon error: bad algorithm");
return false;
}
if ($this->encoding != self::ENCODING) {
- common_log(LOG_DEBUG, "Salmon error: bad encoding");
+ common_debug("Salmon error: bad encoding");
return false;
}
- // $this->data is base64_url_encoded and should contain XML which is passed to getAuthorUri
- $text = Magicsig::base64_url_decode($this->data);
- $signer_uri = $this->getAuthorUri($text);
-
try {
- $magicsig = $this->getKeyPair($signer_uri);
+ $magicsig = $this->getKeyPair($profile, true); // Do discovery too if necessary
} catch (Exception $e) {
- common_log(LOG_DEBUG, "Salmon error: ".$e->getMessage());
+ common_debug("Salmon error: ".$e->getMessage());
return false;
}
- return $magicsig->verify($this->signingText(), $this->sig);
+ if (!$magicsig->verify($this->signingText(), $this->getSignature())) {
+ // TRANS: Client error when incoming salmon slap signature does not verify cryptographically.
+ throw new ClientException(_m('Salmon signature verification failed.'));
+ }
+ $this->setActor($profile);
+ return true;
}
/**
return true;
}
+ public function setActor(Profile $actor)
+ {
+ if ($this->actor instanceof Profile) {
+ throw new ServerException('Cannot set a new actor profile for MagicEnvelope object.');
+ }
+ $this->actor = $actor;
+ }
+
+ public function getActor()
+ {
+ if (!$this->actor instanceof Profile) {
+ throw new ServerException('No actor set for this magic envelope.');
+ }
+ return $this->actor;
+ }
+
/**
* Encode the given string as a signed MagicEnvelope XML document,
* using the keypair for the given local user profile. We can of
* on some systems.
*
* @param string $text XML fragment to sign, assumed to be Atom
- * @param Profile $actor Profile of a local user to use as signer
+ * @param User $user User who cryptographically signs $text
*
- * @return string XML string representation of magic envelope
+ * @return MagicEnvelope object complete with signature
*
* @throws Exception on bad profile input or key generation problems
- * @fixme if signing fails, this seems to return the original text without warning. Is there a reason for this?
*/
- public static function signForProfile($text, Profile $actor)
+ public static function signAsUser($text, User $user)
{
- // We only generate keys for our local users of course, so let
- // getUser throw an exception if the profile is not local.
- $user = $actor->getUser();
-
- // Find already stored key
- $magicsig = Magicsig::getKV('user_id', $user->id);
- if (!$magicsig instanceof Magicsig) {
- // No keypair yet, let's generate one.
- $magicsig = new Magicsig();
- $magicsig->generate($user->id);
- }
-
- $magic_env = self::signMessage($text, 'application/atom+xml', $magicsig);
-
- assert($magic_env instanceof MagicEnvelope);
+ $magic_env = new MagicEnvelope(null, $user->getProfile());
+ $magic_env->signMessage($text, 'application/atom+xml');
return $magic_env;
}
projects / quix0rs-gnu-social.git / blobdiff