Hook up payload filtering into remote SDP update callback, so

it stays effective for re-INVITEs.
sippy · Jul 28, 2024 · 80e9548 · 80e9548
1 parent 82ea7c1
commit 80e9548
Showing 1 changed file with 31 additions and 21 deletions.
diff --git a/sippy/b2bua_radius.py b/sippy/b2bua_radius.py
@@ -148,6 +148,37 @@ def __init__(self, remote_ip, source, req_source, req_target, global_config, pas
         self.pass_headers = pass_headers
         self.req_source = req_source
         self.req_target = req_target
+        if '_allowed_pts' in self.global_config:
+            self.uaA.on_remote_sdp_change = self.filter_SDP
+
+    def filter_SDP(self, body, done_cb):
+        try:
+            body.parse()
+        except SdpParseError as ex:
+            done_cb(None, ex=ex)
+            return
+        except Exception as ex:
+            exx = SdpParseError(f'{ex}')
+            exx.msg = 'Malformed SDP body'
+            exx.code = 400
+            exx.__cause__ = ex
+            done_cb(None, ex=exx)
+            return
+        allowed_pts = self.global_config['_allowed_pts']
+        for sect in body.content.sections:
+            mbody = sect.m_header
+            if mbody.transport.lower() not in self.rtpps_cls.AV_TRTYPES:
+                continue
+            old_len = len(mbody.formats)
+            _allowed_pts = [x if isinstance(x, int) else sect.getPTbyName(x) for x in allowed_pts]
+            mbody.formats = [x for x in mbody.formats if x in _allowed_pts]
+            if len(mbody.formats) == 0:
+                ex = SdpParseError()
+                done_cb(None, ex=ex)
+                return
+            if old_len > len(mbody.formats):
+                sect.optimize_a()
+        done_cb(body)
 
     def recvEvent(self, event, ua):
         if ua == self.uaA:
@@ -161,27 +192,6 @@ def recvEvent(self, event, ua):
                     self.uaA.recvEvent(CCEventFail((500, 'Internal Server Error (1)'), rtime = event.rtime))
                     self.state = CCStateDead
                     return
-                if body != None and '_allowed_pts' in self.global_config:
-                    try:
-                        body.parse()
-                    except:
-                        self.uaA.recvEvent(CCEventFail((400, 'Malformed SDP Body'), rtime = event.rtime))
-                        self.state = CCStateDead
-                        return
-                    allowed_pts = self.global_config['_allowed_pts']
-                    for sect in body.content.sections:
-                        mbody = sect.m_header
-                        if mbody.transport.lower() not in self.rtpps_cls.AV_TRTYPES:
-                            continue
-                        old_len = len(mbody.formats)
-                        _allowed_pts = [x if isinstance(x, int) else sect.getPTbyName(x) for x in allowed_pts]
-                        mbody.formats = [x for x in mbody.formats if x in _allowed_pts]
-                        if len(mbody.formats) == 0:
-                            self.uaA.recvEvent(CCEventFail((488, 'Not Acceptable Here')))
-                            self.state = CCStateDead
-                            return
-                        if old_len > len(mbody.formats):
-                            sect.optimize_a()
                 if self.cld.startswith('nat-'):
                     self.cld = self.cld[4:]
                     if body != None: