diff options
| author | Jacob Erlbeck <jerlbeck@sysmocom.de> | 2014-10-20 16:30:06 +0200 |
|---|---|---|
| committer | Holger Hans Peter Freyther <holger@moiji-mobile.com> | 2014-10-27 11:17:11 +0100 |
| commit | 91e9f555b6a091663c192c9cd3b8d022a2690eed (patch) | |
| tree | 640fe07697e4dd5f319869cc1f2f60dbec8bfeec /openbsc/src/gprs/gb_proxy_tlli.c | |
| parent | e99c333d61bd5ac6fcd842313ffb4196be42fdab (diff) | |
gbproxy: Fix P-TMSI generation for repeated Attach Accept messages
Currently, when P-TMSI patching is enabled, a new BSS P-TMSI is
generated for each Attach Accept. So two duplicated, subsequent
Attach Accept messages will be mapped to different BSS side P-TMSI.
Because the last one will replace former ones in the link_info
struct, the MS will fail to access the SGSN if it uses the former
P-TMSI to derive the new TLLI.
This patch checks the SGSN P-TMSI already assigned to the link_info
and only generates a new BSS P-TMSI on mismatch (or if the BSS P-TMSI
hasn't been set yet).
Ticket: OW#1322
Sponsored-by: On-Waves ehf
Diffstat (limited to 'openbsc/src/gprs/gb_proxy_tlli.c')
| -rw-r--r-- | openbsc/src/gprs/gb_proxy_tlli.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/openbsc/src/gprs/gb_proxy_tlli.c b/openbsc/src/gprs/gb_proxy_tlli.c index 138837eff..467006e87 100644 --- a/openbsc/src/gprs/gb_proxy_tlli.c +++ b/openbsc/src/gprs/gb_proxy_tlli.c @@ -557,9 +557,14 @@ struct gbproxy_link_info *gbproxy_update_link_state_dl( /* A new P-TMSI has been signalled in the message, * register new TLLI */ uint32_t new_sgsn_ptmsi; - uint32_t new_bss_ptmsi; + uint32_t new_bss_ptmsi = GSM_RESERVED_TMSI; gprs_parse_tmsi(parse_ctx->new_ptmsi_enc, &new_sgsn_ptmsi); - new_bss_ptmsi = gbproxy_make_bss_ptmsi(peer, new_sgsn_ptmsi); + + if (link_info->sgsn_tlli.ptmsi == new_sgsn_ptmsi) + new_bss_ptmsi = link_info->tlli.ptmsi; + + if (new_bss_ptmsi == GSM_RESERVED_TMSI) + new_bss_ptmsi = gbproxy_make_bss_ptmsi(peer, new_sgsn_ptmsi); LOGP(DGPRS, LOGL_INFO, "Got new PTMSI %08x from SGSN, using %08x for BSS\n", |