adjust SRP to match clipper change

1 files changed, 12 insertions, 5 deletions

diff --git a/backend/node/src/clipperz.js b/backend/node/src/clipperz.js
index 37b9cae..72b6c9f 100644
--- a/backend/node/src/clipperz.js
+++ b/backend/node/src/clipperz.js
@@ -38,24 +38,26 @@ function clipperz_store(PG) {
      cb(e,e?null:r.rows[0].c);
   }
  ) };
  rv.prototype.clear = function(cb) { PQ.Q(
   "TRUNCATE clipperz.thesession", cb
  ) };
  rv.prototype.__proto__ = express_store.prototype;
  return rv;
 }
 
 var srp_g = BIGNUM(2);
 var srp_n = BIGNUM("115b8b692e0e045692cf280b436735c77a5a9e8a9e7ed56c965f87db5b2a2ece3",16);
+var srp_k = BIGNUM("64398bff522814e306a97cb9bfc4364b7eed16a8c17c5208a40a2bad2933c8e",16);
+var srp_hn = "597626870978286801440197562148588907434001483655788865609375806439877501869636875571920406529";
 var n123 = '112233445566778899aabbccddeeff00112233445566778899aabbccddeeff00';
 
 
 var CLIPPERZ = module.exports = function(CONFIG) {
 
  var LOGGER = CONFIG.logger||{trace:function(){}};
 
  var PG = {
   url: CONFIG.psql,
   PG: require('pg').native,
   Q: function(q,a,cb) {
    if('function'===typeof a) cb=a,a=[];
@@ -166,37 +168,42 @@ var CLIPPERZ = module.exports = function(CONFIG) {
          if(!r.rowCount) return cb(new Error('no OTP found'));
          r=r.rows[0];
          if(!r.yes) return cb(new Error('OTP is in a sorry state'));
          cb(null,{ref:r.otp_ref});
         });
        }]
       },function(e,r) {
        if(e) return cb(e);
        req.session.C = ppp.C; req.session.A = ppp.A;
        req.session.s = r.u.u_srp_s; req.session.v = r.u.u_srp_v;
        req.session.u = r.u.u_id;
        req.session.b = clipperz_random();
-       req.session.B = BIGNUM(req.session.v,16).add(srp_g.powm(BIGNUM(req.session.b,16),srp_n)).toString(16);
+       req.session.B = srp_k.mul(BIGNUM(req.session.v,16)).add(srp_g.powm(BIGNUM(req.session.b,16),srp_n)).toString(16);
        var rv = {s:req.session.s,B:req.session.B}
        if(r.otp && r.otp.otp_ref) rv.oneTimePassword=r.otp.otp_ref;
        res.res(rv);
       });
  
       case 'credentialCheck':
-       var u = clipperz_hash(BIGNUM(req.session.B,16).toString(10));
+       var u = clipperz_hash(BIGNUM(req.session.A,16).toString(10)+BIGNUM(req.session.B,16).toString(10));
        var A = BIGNUM(req.session.A,16);
-       var S = A.mul(BIGNUM(req.session.v,16).powm(BIGNUM(u,16),srp_n)).powm(
-                BIGNUM(req.session.b,16), srp_n);
+       var S = A.mul(BIGNUM(req.session.v,16).powm(BIGNUM(u,16),srp_n)).powm(BIGNUM(req.session.b,16),srp_n);
        var K = clipperz_hash(S.toString(10));
-       var M1 = clipperz_hash(A.toString(10)+BIGNUM(req.session.B,16).toString(10)+K.toString(16));
+       var M1 = clipperz_hash(
+                 srp_hn
+                 +clipperz_hash(req.session.C)
+                 +BIGNUM(req.session.s,16).toString(10)
+                 +A.toString(10)
+                 +BIGNUM(req.session.B,16).toString(10)
+                 +K );
        if(M1!=ppp.M1) return res.res({error:'?'});
        req.session.K = K;
        var M2 = clipperz_hash(A.toString(10)+M1+K.toString(16));
        return res.res({M2:M2,connectionId:'',loginInfo:{latest:{},current:{}},offlineCopyNeeded:false,lock:'----'});
 
       case 'oneTimePassword': return PG.Q(
         "UPDATE clipperz.theotp AS otp"
        +" SET"
        +"  otps_id = CASE WHEN s.otps_code!='ACTIVE' THEN s.otps_id ELSE ("
        +"   SELECT ss.otps_id FROM clipperz.otpstatus AS ss WHERE ss.otps_code=CASE"
        +"    WHEN otp.otp_key_checksum=$2 THEN 'REQUESTED'"
        +"    ELSE 'DISABLED' END"