net/restund/patches/200-turn-block-forwarding-to-loopback-any.patch

   1 From ffa2d56cac3d37715fe1381df81802774240da92 Mon Sep 17 00:00:00 2001
   2 From: Dusan Stevanovic <dule@wire.com>
   3 Date: Thu, 11 Mar 2021 10:58:32 +0100
   4 Subject: [PATCH] turn: block forwarding to loopback/any
   5
   6 ---
   7  modules/turn/turn.c | 18 ++++++++++++++----
   8  1 file changed, 14 insertions(+), 4 deletions(-)
   9
  10 --- a/modules/turn/turn.c
  11 +++ b/modules/turn/turn.c
  12 @@ -153,6 +153,7 @@ static bool indication_handler(struct re
  13         struct stun_attr *data, *peer;
  14         struct allocation *al;
  15         struct perm *perm;
  16 +       const struct sa *psa;
  17         int err;
  18         (void)sock;
  19         (void)ctx;
  20 @@ -173,13 +174,17 @@ static bool indication_handler(struct re
  21         if (!peer || !data)
  22                 return true;
  23
  24 -       perm = perm_find(al->perms, &peer->v.xor_peer_addr);
  25 +       psa = &peer->v.xor_peer_addr;
  26 +       perm = perm_find(al->perms, psa);
  27         if (!perm) {
  28                 ++al->dropc_tx;
  29                 return true;
  30         }
  31
  32 -       err = udp_send(al->rel_us, &peer->v.xor_peer_addr, &data->v.data);
  33 +       if (sa_is_loopback(psa) || sa_is_any(psa))
  34 +               err = EPERM;
  35 +       else
  36 +               err = udp_send(al->rel_us, psa, &data->v.data);
  37         if (err)
  38                 turnd.errc_tx++;
  39         else {
  40 @@ -200,6 +205,7 @@ static bool raw_handler(int proto, const
  41         uint16_t numb, len;
  42         struct perm *perm;
  43         struct chan *chan;
  44 +       const struct sa *psa;
  45         int err;
  46
  47         al = allocation_find(proto, src, dst);
  48 @@ -219,7 +225,8 @@ static bool raw_handler(int proto, const
  49         if (!chan)
  50                 return false;
  51
  52 -       perm = perm_find(al->perms, chan_peer(chan));
  53 +       psa = chan_peer(chan);
  54 +       perm = perm_find(al->perms, psa);
  55         if (!perm) {
  56                 ++al->dropc_tx;
  57                 return false;
  58 @@ -227,7 +234,10 @@ static bool raw_handler(int proto, const
  59
  60         mb->end = mb->pos + len;
  61
  62 -       err = udp_send(al->rel_us, chan_peer(chan), mb);
  63 +       if (sa_is_loopback(psa) || sa_is_any(psa))
  64 +               err = EPERM;
  65 +       else
  66 +               err = udp_send(al->rel_us, psa, mb);
  67         if (err)
  68                 turnd.errc_tx++;
  69         else {