policy: purge pointer-casting where not necessary

Casting is dangerous, e.g. it's easy to misconfigure policy with
  policy.add(policy.FORWARD('some address'))
which lead to segfault without showing any indication of the cause.
Now this case will show as
  .../policy.lua:98: 'struct kr_query' has no member named 'current'
and only abort the policy module instead of the whole process.

diff --git a/daemon/lua/kres.lua.in b/daemon/lua/kres.lua.in
index 540c7f99f866487739606ef8837100456faba18f..f302a08a31fd583e1353ce6f96dd9f4d115c7b98 100644 (file)
--- a/daemon/lua/kres.lua.in
+++ b/daemon/lua/kres.lua.in
@@ -346,7 +346,7 @@ kres = {
        rcode = ffi.new('struct pkt_rcode'),
        query = query_flag,
        CONSUME = 1, PRODUCE = 2, DONE = 4, FAIL = 8, YIELD = 16,
-       -- Metatypes
+       -- Metatypes.  Beware that any pointer will be cast silently...
        pkt_t = function (udata) return ffi.cast('knot_pkt_t *', udata) end,
        request_t = function (udata) return ffi.cast('struct kr_request *', udata) end,
        -- Global API functions

diff --git a/modules/policy/policy.lua b/modules/policy/policy.lua
index 8385585fb293fd852ffd4ceb1a2b6aae3aa163d6..2c19ed85415ac12658e468cb7bf28b39c7ef01a0 100644 (file)
--- a/modules/policy/policy.lua
+++ b/modules/policy/policy.lua
@@ -55,7 +55,6 @@ local function mirror(target)
        if not sink then panic('MIRROR target %s is not a valid: %s', target, err) end
        return function(state, req)
                if state == kres.FAIL then return state end
-               req = kres.request_t(req)
                local query = req.qsource.packet
                if query ~= nil then
                        sink:send(ffi.string(query.wire, query.size))
@@ -76,7 +75,6 @@ local function stub(target)
                table.insert(list, addr2sock(target))
        end
        return function(state, req)
-               req = kres.request_t(req)
                local qry = req:current()
                -- Switch mode to stub resolver, do not track origin zone cut since it's not real authority NS
                qry.flags = bit.band(bit.bor(qry.flags, kres.query.STUB), bit.bnot(kres.query.ALWAYS_CUT))
@@ -97,7 +95,6 @@ local function forward(target)
                table.insert(list, addr2sock(target))
        end
        return function(state, req)
-               req = kres.request_t(req)
                local qry = req:current()
                req.options = bit.bor(bit.bor(req.options, kres.query.FORWARD), kres.query.NO_MINIMIZE)
                qry.flags = bit.band(bit.bor(qry.flags, kres.query.FORWARD), bit.bnot(kres.query.ALWAYS_CUT))
@@ -122,7 +119,6 @@ end
 -- Set and clear some query flags
 local function flags(opts_set, opts_clear)
        return function(state, req)
-               req = kres.request_t(req)
                local qry = req:current()
                qry.flags = bit.band(bit.bor(qry.flags, opts_set or 0), bit.bnot(opts_clear or 0))
                return nil -- chain rule