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#### Type Of Change - [ ] Small bug fix (non-breaking change which fixes an issue) - [x] New feature (non-breaking change which adds new functionality) - [ ] Breaking change (fix or feature that would change existing functionality)

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#### Description

`loose_route()` in `rr` checks request src ip/port against ip/port in flow tokens to detect direction and decide whether to apply flow tokens routing: ``` static inline int process_outbound(struct sip_msg *_m, str flow_token) { ... } else if(!ip_addr_cmp(&rcv->src_ip, &_m->rcv.src_ip) || rcv->src_port != _m->rcv.src_port) { LM_DBG(""incoming" request found. Using flow-token for " "routing\n"); ... ```

there are cases when remote UA changes ip/port for in-dialog messages and this approach does not work. incoming message has route set with flow tokens and src ip/port different from ones in the flow tokens. as a result, `loose_route()` routes message back to the client using flow tokens instead of using the normal part of the Route headers as expected.

new `force_lr_no_outbound_flag` allows to control flow tokens usage in the `loose_route()` when we know direction based on the some high level config logic (for example: by the result of `ds_is_from_list()` call)

You can view, comment on, or merge this pull request online at:

https://github.com/kamailio/kamailio/pull/4280

-- Commit Summary --

* rr: add force_lr_no_outbound_flag param

-- File Changes --

M src/modules/rr/doc/rr_admin.xml (17) M src/modules/rr/loose.c (6) M src/modules/rr/rr_mod.c (9)

-- Patch Links --

https://github.com/kamailio/kamailio/pull/4280.patch https://github.com/kamailio/kamailio/pull/4280.diff