Principal Service: Add support for multiple user accounts

services/vanadium/security/wire_blessings.go

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package main
 
 import vpkg "mojo/services/vanadium/security/interfaces/principal"
 
 // wireBlessings encapsulates wire format of a set of a Vanadium blessings
 // and the corresponding cryptographic proof that binds them to a principal
@@ skipping 39 matching lines @@
 // Given a Hash, the message digest of a caveat is:
 // Hash(Hash(Id), Hash(ParamVom))
 type caveat struct {
         Id       [16]byte // The identifier of the caveat validation function.
         ParamVom []byte   // VOM-encoded bytes of the parameters to be provided to the validation function.
 }
 
 func newBlessing(wb *wireBlessings) *vpkg.Blessing {
         // TODO(ataly, gauthamt): Below we only consider the first certificate chain
         // in the wireBlessings object. We should handle the case when the wireBlessings
-        // object has more than one certificate chain.
-        // TODO(ataly, gauthamt): We should validate all caveats present in the certificates.
+        // object has more than one certificate chain. This issue would become moot
+        // if the vpkg.Blessing type matched the wireBlessing type.
+        // TODO(ataly, gauthamt): We should validate all caveats present in the
+        // certificates.
         var chain []vpkg.Certificate
         for _, c := range wb.CertificateChains[0] {
                 chain = append(chain, vpkg.Certificate{Extension: c.Extension})
         }
         return &vpkg.Blessing{chain}
 }