Windshaft-cartodb/lib/cartodb/signed_maps.js
2014-02-14 17:07:52 +01:00

402 lines
13 KiB
JavaScript

var crypto = require('crypto');
var Step = require('step');
var _ = require('underscore');
var debug = global.environment ? global.environment.debug : undefined;
// Class handling map signatures and user certificates
//
// See https://github.com/CartoDB/Windshaft-cartodb/wiki/Signed-maps
//
// @param redis_pool an instance of a "redis-mpool"
// See https://github.com/CartoDB/node-redis-mpool
// Needs version 0.x.x of the API.
//
function SignedMaps(redis_pool) {
this.redis_pool = redis_pool;
// Database containing signatures
// TODO: allow configuring ?
// NOTE: currently it is the same as
// the one containing layergroups
this.db_signatures = 0;
//
// Map signatures in redis are reference to signature certificates
// We have the following datastores:
//
// 1. User certificates: set of per-user authorization certificates
// 2. Map signatures: set of per-map certificate references
// 3. Certificate applications: set of per-certificate signed maps
// User certificates (HASH:crt_id->crt_val)
this.key_map_crt = "map_crt|<%= signer %>";
// Map signatures (SET:crt_id)
this.key_map_sig = "map_sig|<%= signer %>|<%= map_id %>";
// Certificates applications (SET:map_id)
//
// Everytime a map is signed, the map identifier (layergroup_id)
// is added to this set. The purpose of this set is to drop
// all map signatures when a certificate is removed
//
this.key_crt_sig = "crt_sig|<%= signer %>|<%= crt_id %>";
};
var o = SignedMaps.prototype;
//--------------- PRIVATE METHODS --------------------------------
o._acquireRedis = function(callback) {
this.redis_pool.acquire(this.db_signatures, callback);
};
o._releaseRedis = function(client) {
this.redis_pool.release(this.db_signatures, client);
};
/**
* Internal function to communicate with redis
*
* @param redisFunc - the redis function to execute
* @param redisArgs - the arguments for the redis function in an array
* @param callback - function to pass results too.
*/
o._redisCmd = function(redisFunc, redisArgs, callback) {
var redisClient;
var that = this;
var db = that.db_signatures;
Step(
function getRedisClient() {
that.redis_pool.acquire(db, this);
},
function executeQuery(err, data) {
if ( err ) throw err;
redisClient = data;
redisArgs.push(this);
redisClient[redisFunc.toUpperCase()].apply(redisClient, redisArgs);
},
function releaseRedisClient(err, data) {
if ( ! _.isUndefined(redisClient) ) that.redis_pool.release(db, redisClient);
callback(err, data);
}
);
};
o._getAuthMethod = function(auth) {
return auth.method || 'open';
};
//--------------- PUBLIC API -------------------------------------
/// Check formal validity of a certificate
//
/// Return an Error instance if invalid, null otherwise
///
o.checkInvalidCertificate = function(cert) {
//console.log("Checking cert: "); console.dir(cert);
if ( cert.version !== "0.0.1" ) {
return new Error("Unsupported certificate version " + cert.version);
}
if ( ! cert.auth ) {
console.log("Cert is : "); console.dir(cert);
return new Error("No certificate authorization");
}
var method = this._getAuthMethod(cert.auth);
switch ( method ) {
case 'open':
break;
case 'token':
if ( ! _.isArray(cert.auth.valid_tokens) )
return new Error("Invalid 'token' authentication: missing valid_tokens");
if ( ! cert.auth.valid_tokens.length )
return new Error("Invalid 'token' authentication: no valid_tokens");
break;
default:
return new Error("Unsupported authentication method: " + cert.auth.method);
break;
}
return null; // all valid
}
// Check if the given certificate authorizes waiver of "auth"
o.authorizedByCert = function(cert, auth) {
var err = this.checkInvalidCertificate(cert);
if ( err ) throw err;
var method = this._getAuthMethod(cert.auth);
// Open authentication certificates are always authorized
if ( method === 'open' ) return true;
// Token based authentication requires valid token
if ( method === 'token' ) {
var found = cert.auth.valid_tokens.indexOf(auth);
//if ( found !== -1 ) {
//console.log("Token " + auth + " is found at position " + found + " in valid tokens " + cert.auth.valid_tokens);
// return true;
//} else return false;
return cert.auth.valid_tokens.indexOf(auth) !== -1;
}
throw new Error("Unsupported authentication method: " + cert.auth.method);
};
// Check if shown credential are authorized to access a map
// by the given signer.
//
// @param signer a signer name (cartodb username)
// @param map_id a layergroup_id
// @param auth an authentication token, or undefined if none
// (can still be authorized by signature)
//
// @param callback function(Error, Boolean)
//
o.isAuthorized = function(signer, map_id, auth, callback) {
var that = this;
var redisClient;
var db = that.db_signatures;
var authorized = false;
var certificate_id_list;
var missing_certificates = [];
if ( debug ) {
console.log("Check auth from signer '" + signer + "' on map '" + map_id + "' with auth '" + auth + "'");
}
Step(
function getRedisClient() {
that.redis_pool.acquire(db, this);
},
function getMapSignatures(err, client) {
if ( err ) throw err;
redisClient = client;
var map_sig_key = _.template(that.key_map_sig, {signer:signer, map_id:map_id});
redisClient.SMEMBERS(map_sig_key, this);
//that._redisCmd('SMEMBERS', [ map_sig_key ], this);
},
function getCertificates(err, crt_lst) {
if ( err ) throw err;
if ( debug ) {
console.log("Map '" + map_id + "' is signed by " + crt_lst.length + " certificates of user '" + signer);
}
certificate_id_list = crt_lst;
if ( ! crt_lst.length ) {
// No certs, avoid calling redis with short args list.
// Next step expects a list of certificate values so
// we directly send the empty list.
return crt_lst;
}
var map_crt_key = _.template(that.key_map_crt, {signer:signer});
//that._redisCmd('HMGET', [ map_crt_key ].concat(crt_lst), this);
redisClient.HMGET(map_crt_key, crt_lst, this);
},
function checkCertificates(err, certs) {
if ( err ) throw err;
for (var i=0; i<certs.length; ++i) {
var crt_id = certificate_id_list[i];
if ( _.isNull(certs[i]) ) {
missing_certificates.push(crt_id);
continue;
}
var cert;
try {
//console.log("cert " + crt_id + ": " + certs[i]);
cert = JSON.parse(certs[i]);
authorized = that.authorizedByCert(cert, auth);
} catch (err) {
console.log("Certificate " + certificate_id_list[i] + " by user '" + signer + "' is malformed: " + err);
continue;
}
if ( authorized ) {
if ( debug ) {
console.log("Access to map '" + map_id + "' authorized by cert '"
+ certificate_id_list[i] + "' of user '" + signer + "'");
}
//console.dir(cert);
break; // no need to further check certs
}
}
return null;
},
function finish(err) {
if ( missing_certificates.length ) {
console.log("WARNING: map '" + map_id + "' is signed by '" + signer
+ "' with " + missing_certificates.length
+ " missing certificates: "
+ missing_certificates + " (TODO: give cleanup instructions)");
}
if ( redisClient ) that.redis_pool.release(db, redisClient);
callback(err, authorized);
}
);
};
// Add an authorization certificate from a user.
//
// @param signer a signer name (cartodb username)
// @param cert certificate object, see
// http://github.com/CartoDB/Windshaft-cartodb/wiki/Signed-maps
//
// @param callback function(err, crt_id) return certificate id
//
// TODO: allow for requesting error when certificate already exists ?
//
o.addCertificate = function(signer, cert, callback) {
var crt_val = JSON.stringify(cert);
var crt_id = crypto.createHash('md5').update(crt_val).digest('hex');
var usr_crt_key = _.template(this.key_map_crt, {signer:signer});
this._redisCmd('HSET', [ usr_crt_key, crt_id, crt_val ], function(err, created) {
// NOTE: created would be 0 if the field already existed, 1 otherwise
callback(err, crt_id);
});
};
// Remove an authorization certificate of a user, also removing
// any signature made with the certificate.
//
// @param signer a signer name (cartodb username)
// @param crt_id certificate identifier, as returned by addCertificate
// @param callback function(err)
//
o.delCertificate = function(signer, crt_id, callback) {
var db = this.db_signatures;
var crt_sig_key = _.template(this.key_crt_sig, {signer:signer, crt_id:crt_id});
var signed_map_list;
var redis_client;
var that = this;
Step (
function getRedisClient() {
that._acquireRedis(this);
},
function removeCertificate(err, data) {
if ( err ) throw err;
redis_client = data;
// Remove the certificate (would be enough to stop authorizing uses)
var usr_crt_key = _.template(that.key_map_crt, {signer:signer});
redis_client.HDEL(usr_crt_key, crt_id, this);
},
function getMapSignatures(err, deleted) {
if ( err ) throw err;
if ( ! deleted ) {
// debugging (how can this be possible?)
console.log("WARNING: authorization certificate '" + crt_id
+ "' by user '" + signer + "' did not exist on delete request");
}
// Get all signatures by this certificate
redis_client.SMEMBERS(crt_sig_key, this);
},
function delMapSignaturesReference(err, map_id_list) {
if ( err ) throw err;
signed_map_list = map_id_list;
if ( debug ) {
console.log("Certificate '" + crt_id + "' from user '" + signer
+ "' was used to sign " + signed_map_list.length + " maps");
}
redis_client.DEL(crt_sig_key, this);
},
function delMapSignatures(err) {
if ( err ) throw err;
var crt_sig_key = _.template(that.key_crt_sig, {signer:signer, crt_id:crt_id});
var tx = redis_client.MULTI();
for (var i=0; i<signed_map_list.length; ++i) {
var map_id = signed_map_list[i];
var map_sig_key = _.template(that.key_map_sig, {signer:signer, map_id:map_id});
//console.log("Queuing removal of '" + crt_id + "' from '" + map_sig_key + "'");
tx.SREM( map_sig_key, crt_id )
}
tx.EXEC(this);
},
function reportTransaction(err, rets) {
if ( err ) throw err;
if ( debug ) {
for (var i=0; i<signed_map_list.length; ++i) {
var ret = rets[i];
if ( ! ret ) {
console.log("No signature with certificate '" + crt_id
+ "' of user '" + signer + "' found in map '"
+ signed_map_list[i] + "'");
} else {
console.log("Signature with certificate '" + crt_id
+ "' of user '" + signer + "' removed from map '"
+ signed_map_list[i] + "'");
}
}
}
return null;
},
function finish(err) {
if ( ! _.isUndefined(redis_client) ) {
that._releaseRedis(redis_client);
}
callback(err);
}
);
};
// Sign a map with a certificate reference
//
// @param signer a signer name (cartodb username)
// @param map_id a layergroup_id
// @param crt_id signature certificate identifier
//
// @param callback function(Error)
//
o.signMap = function(signer, map_id, crt_id, callback) {
var that = this;
Step(
function addMapSignature() {
var map_sig_key = _.template(that.key_map_sig, {signer:signer, map_id:map_id});
if ( debug ) {
console.log("Adding " + crt_id + " to " + map_sig_key);
}
that._redisCmd('SADD', [ map_sig_key, crt_id ], this);
},
function addCertificateUsage(err) {
// Add the map to the set of maps signed by the given cert
if ( err ) throw err;
var crt_sig_key = _.template(that.key_crt_sig, {signer:signer, crt_id:crt_id});
that._redisCmd('SADD', [ crt_sig_key, map_id ], this);
},
function finish(err) {
callback(err);
}
);
};
// Sign a map with a full certificate
//
// @param signer a signer name (cartodb username)
// @param map_id a layergroup_id
// @param cert_id signature certificate identifier
//
// @param callback function(Error, String) return certificate id
//
o.addSignature = function(signer, map_id, cert, callback) {
var that = this;
var certificate_id;
Step(
function addCertificate() {
that.addCertificate(signer, cert, this);
},
function signMap(err, cert_id) {
if ( err ) throw err;
if ( ! cert_id ) throw new Error("addCertificate returned no certificate id");
certificate_id = cert_id;
that.signMap(signer, map_id, cert_id, this);
},
function finish(err) {
callback(err, certificate_id);
}
);
};
module.exports = SignedMaps;