28 Sep
2021
28 Sep
'21
3:54 p.m.
Hello,
To be accurate: I am going to implement this change and would like to know, if the PR
would be accepted by the community.
BR
Theo
Von: sr-dev <sr-dev-bounces(a)lists.kamailio.org> Im Auftrag von Scherney Theodor
Gesendet: Mittwoch, 22. September 2021 09:24
An: 'sr-dev(a)lists.kamailio.org' <sr-dev(a)lists.kamailio.org>
Cc: Onic Roman <Roman.Onic(a)kontron.com>om>; Valentin Christoph
<Christoph.Valentin(a)kontron.com>
Betreff: [sr-dev] Syntax error
Hello,
I have tested following scenario:
Alice "calls" Bob. Call is established.
At the end of the call, Bob disconnects (hangs up) first and generates a BYE message.
If there is a syntax error in FROM Header of BYE message, a 400 “Bad From header” is
responded by the Proxy.
If there is a syntax error in TO Header of BYE message, the message is discarded.
According RFC 3261 this is not correct.
Is it okay, to implement the same logic for TO Header as done for FROM Header?
RFC 3261:
16.2 Stateful Proxy
……….
For all new requests, including any with unknown methods, an element intending to proxy
the request MUST:
1. Validate the request (Section 16.3)
2. Preprocess routing information (Section 16.4)
3. Determine target(s) for the request (Section 16.5)
+--------------------+
| | +---+
| | | C |
| | | T |
| | +---+
+---+ | Proxy | +---+ CT = Client Transaction
| S | | "Higher" Layer | | C |
| T | | | | T | ST = Server Transaction
+---+ | | +---+
| | +---+
| | | C |
| | | T |
| | +---+
+--------------------+
Figure 3: Stateful Proxy Model
4. Forward the request to each target (Section 16.6)
5. Process all responses (Section 16.7)
16.3 Request Validation
Before an element can proxy a request, it MUST verify the message’s validity.
A valid message must pass the following checks:
1. Reasonable Syntax
2. URI scheme
3. Max-Forwards
4. (Optional) Loop Detection
5. Proxy-Require
6. Proxy-Authorization
If any of these checks fail, the element MUST behave as a user agent server (see
Section 8.2) and respond with an error code.
LOGs:
BYE with syntax error in FROM header:
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/parse_addr_spec.c:555]:
parse_to_param(): unexpected end of header, status 20:
[;transport=UDP;tag=b3af-8e5a-1e36-79340f18;#015] .
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/parse_addr_spec.c:881]:
parse_addr_spec(): invalid To - unexpected end of header in state 11
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/parse_from.c:75]:
parse_from_header(): bad From header
[sip:catt180@vict-ims.net;transport=UDP;tag=b3af-8e5a-1e36-79340f18;]
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="pv"] ERROR: pv [pv_core.c:468]: pv_get_from_attr(): cannot parse From
header
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="xlog"] INFO: <script>: route BYE (<null>
(193.154.113.40:5065) to sip:catt181@vict-ims.net, 1632235417904catt180, )
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="xlog"] INFO: <script>: BYE (BYE
sip:catt181@193.154.113.40:5065;transport=UDP;rinstance=317-catt181 SIP/2.0#015#012From:
sip:catt180@vict-ims.net;transport=UDP;tag=b3af-8e5a-1e36-79340f18;#015#012To:
sip:catt181@vict-ims.net;transport=UDP;tag=9d7b-d1c6-c06b-7a1dbec7#015#012Call-ID:
1632235417904catt180#015#012CSeq: 2 BYE#015#012Contact:
sip:catt180@193.154.113.40:5065;transport=UDP;rinstance=317-catt180#015#012Content-Length:
0#015#012Max-Forwards: 70#015#012Route:
sip:mo@172.29.21.60;r2=on;lr;ftag=b3af-8e5a-1e36-79340f18;rm=8;did=8ed.6e12#015#012Route:
sip:mo@pcscf-1.vict-ims.net:5060;r2=on;lr;ftag=b3af-8e5a-1e36-79340f18;rm=8;did=8ed.6e12#015#012Route:
sip:mo@vict-ims.net;lr;ftag=b3af-8e5a-1e36-79340f18;did=8ed.e7b1#015#012Route:
sip:mt@vict-ims.net;lr;ftag=b3af-8e5a-1e36-79340f18;did=8ed.e7b1#015#012Route:
sip:mt@pcscf-1.vict-ims.net;r2=on;lr;ftag=b3af-8e5a-1e36-79340f18;rm=7;did=8ed.7e12#015#012Route:
sip:mt@172.29.21.60:5060;r2=on;lr;ftag=b3af-8e5a-1e36-79340f18;rm=7;did=8ed.7e12#015#012Via:
SIP/2.0/UDP 193.154.113.40:5065;branch=z9hG4bKf7057b36-0#015#012#015#012)
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/parse_addr_spec.c:555]:
parse_to_param(): unexpected end of header, status 20:
[;transport=UDP;tag=b3af-8e5a-1e36-79340f18;#015] .
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/parse_addr_spec.c:881]:
parse_addr_spec(): invalid To - unexpected end of header in state 11
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="sanity"] WARNING: sanity [sanity.c:776]: check_parse_uris(): failed to
parse From header [sip:catt180@vict-ims.net;transport=UDP;tag=b3af-8e5a-1e36-79340f18;]
Sep 21 16:44:51 vict2-ims3 /usr/sbin/kamailio[12723]: [logSDID@20306
resource="xlog"] INFO: <script>: t_relay_send_reply_sl - BYE (SIP/2.0 400
Bad From header#015#012From:
sip:catt180@vict-ims.net;transport=UDP;tag=b3af-8e5a-1e36-79340f18;#015#012To:
sip:catt181@vict-ims.net;transport=UDP;tag=9d7b-d1c6-c06b-7a1dbec7#015#012Call-ID:
1632235417904catt180#015#012CSeq: 2 BYE#015#012Via: SIP/2.0/UDP
193.154.113.40:5065;branch=z9hG4bKf7057b36-0#015#012Server: Kamailio
P-CSCF#015#012Content-Length: 0#015#012#015#012)
BYE with syntax error in TO header:
Sep 21 16:41:07 vict2-ims3 /usr/sbin/kamailio[12733]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/parse_addr_spec.c:555]:
parse_to_param(): unexpected end of header, status 20:
[;transport=UDP;tag=1ba4-ff0c-82af-415174d1;#015#012] .
Sep 21 16:41:07 vict2-ims3 /usr/sbin/kamailio[12733]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/parse_addr_spec.c:881]:
parse_addr_spec(): invalid To - unexpected end of header in state 13
Sep 21 16:41:07 vict2-ims3 /usr/sbin/kamailio[12733]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/msg_parser.c:167]:
get_hdr_field(): bad to header
Sep 21 16:41:07 vict2-ims3 /usr/sbin/kamailio[12733]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/msg_parser.c:337]:
parse_headers(): bad header field [To: sip:catt181@vict]
Sep 21 16:41:07 vict2-ims3 /usr/sbin/kamailio[12733]: [logSDID@20306
resource="core"] ERROR: <core> [core/parser/msg_parser.c:687]:
parse_msg(): ERROR: parse_msg: message=<BYE
sip:catt181@193.154.113.40:5065;transport=UDP;rinstance=317-catt181 SIP/2.0#015#012From:
sip:catt180@vict-ims.net;transport=UDP;tag=b7fb-dd8f-30fd-2a93fc86#015#012To:
sip:catt181@vict-ims.net;transport=UDP;tag=1ba4-ff0c-82af-415174d1;#015#012Call-ID:
1632235194213catt180#015#012CSeq: 2 BYE#015#012Contact:
sip:catt180@193.154.113.40:5065;transport=UDP;rinstance=317-catt180#015#012Content-Length:
0#015#012Max-Forwards: 70#015#012Route:
sip:mo@172.29.21.60;r2=on;lr;ftag=b7fb-dd8f-30fd-2a93fc86;rm=8;did=281.c9a1#015#012Route:
sip:mo@pcscf-1.vict-ims.net:5060;r2=on;lr;ftag=b7fb-dd8f-30fd-2a93fc86;rm=8;did=281.c9a1#015#012Route:
sip:mo@vict-ims.net;lr;ftag=b7fb-dd8f-30fd-2a93fc86;did=281.b871#015#012Route:
sip:mt@vict-ims.net;lr;ftag=b7fb-dd8f-30fd-2a93fc86;did=281.b871#015#012Route:
sip:mt@pcscf-1.vict-ims.net;r2=on;lr;ftag=b7fb-dd8f-30fd-2a93fc86;rm=7;did=281.d9a1#015#012Route:
sip:mt@172.29.21.60:5060;r2=on;lr;ftag=b7fb-dd8f-30fd-2a93fc86;rm=7;did=281.d9a1#015#012Via:
SIP/2.0/UDP 193.154.113.40:5065;branch=z9hG4bK0850615e-0#015#012#015#012>
Sep 21 16:41:07 vict2-ims3 /usr/sbin/kamailio[12733]: [logSDID@20306
resource="core"] ERROR: <core> [core/receive.c:199]: receive_msg(): core
parsing of SIP message failed (193.154.113.40:5065/1)
BR
Theo