gbproxy: Refactor gbprox_patch_raid(), use different RAI types properly
Currently gbprox_patch_raid() updates the local MCC/MNC with every
BSS originated message, even if the RAI is an 'old' one.
This patch separates state updating and patching into 2 functions
gbprox_update_current_raid and gbprox_patch_raid. In addition, a
field named old_raid_enc is added to gbproxy_parse_context, which is
used for 'old RAI' IEs in Attach Requests and RA Update Requests.
Only the bssg_raid_enc in BSS originated message is used to update
the BSS side 'local' MCC/MNC.
Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/gprs/gb_proxy.c b/openbsc/src/gprs/gb_proxy.c
index 0d738aa..eb1a699 100644
--- a/openbsc/src/gprs/gb_proxy.c
+++ b/openbsc/src/gprs/gb_proxy.c
@@ -409,6 +409,7 @@
uint8_t *ptmsi_enc;
uint8_t *new_ptmsi_enc;
uint8_t *raid_enc;
+ uint8_t *old_raid_enc;
uint8_t *bssgp_raid_enc;
uint8_t *bssgp_ptimsi;
@@ -418,6 +419,7 @@
int need_decryption;
uint32_t tlli;
int pdu_type;
+ int old_raid_matches;
};
struct gbproxy_tlli_info *gbprox_find_tlli(struct gbproxy_peer *peer,
@@ -821,13 +823,51 @@
return need_at_least <= peer->cfg->patch_mode;
}
-/* patch RA identifier in place, update peer accordingly */
-static void gbprox_patch_raid(uint8_t *raid_enc, struct gbproxy_peer *peer,
- int to_bss, const char *log_text)
+/* update peer according to the BSS message */
+static void gbprox_update_current_raid(uint8_t *raid_enc,
+ struct gbproxy_peer *peer,
+ const char *log_text)
{
struct gbproxy_patch_state *state = &peer->patch_state;
const int old_local_mcc = state->local_mcc;
const int old_local_mnc = state->local_mnc;
+ struct gprs_ra_id raid;
+
+ if (!raid_enc)
+ return;
+
+ gsm48_parse_ra(&raid, raid_enc);
+
+ /* save source side MCC/MNC */
+ if (!peer->cfg->core_mcc || raid.mcc == peer->cfg->core_mcc) {
+ state->local_mcc = 0;
+ } else {
+ state->local_mcc = raid.mcc;
+ }
+
+ if (!peer->cfg->core_mnc || raid.mnc == peer->cfg->core_mnc) {
+ state->local_mnc = 0;
+ } else {
+ state->local_mnc = raid.mnc;
+ }
+
+ if (old_local_mcc != state->local_mcc ||
+ old_local_mnc != state->local_mnc)
+ LOGP(DGPRS, LOGL_NOTICE,
+ "Patching RAID %sactivated, msg: %s, "
+ "local: %d-%d, core: %d-%d\n",
+ state->local_mcc || state->local_mnc ?
+ "" : "de",
+ log_text,
+ state->local_mcc, state->local_mnc,
+ peer->cfg->core_mcc, peer->cfg->core_mnc);
+}
+
+/* patch RA identifier in place */
+static void gbprox_patch_raid(uint8_t *raid_enc, struct gbproxy_peer *peer,
+ int to_bss, const char *log_text)
+{
+ struct gbproxy_patch_state *state = &peer->patch_state;
int old_mcc;
int old_mnc;
struct gprs_ra_id raid;
@@ -839,20 +879,11 @@
if (!to_bss) {
/* BSS -> SGSN */
- /* save BSS side MCC/MNC */
- if (!peer->cfg->core_mcc || raid.mcc == peer->cfg->core_mcc) {
- state->local_mcc = 0;
- } else {
- state->local_mcc = raid.mcc;
+ if (state->local_mcc)
raid.mcc = peer->cfg->core_mcc;
- }
- if (!peer->cfg->core_mnc || raid.mnc == peer->cfg->core_mnc) {
- state->local_mnc = 0;
- } else {
- state->local_mnc = raid.mnc;
+ if (state->local_mnc)
raid.mnc = peer->cfg->core_mnc;
- }
} else {
/* SGSN -> BSS */
if (state->local_mcc)
@@ -862,18 +893,6 @@
raid.mnc = state->local_mnc;
}
- if (old_local_mcc != state->local_mcc ||
- old_local_mnc != state->local_mnc)
- LOGP(DGPRS, LOGL_NOTICE,
- "Patching RAID %sactivated, msg: %s, "
- "local: %d-%d, core: %d-%d, to %s\n",
- state->local_mcc || state->local_mnc ?
- "" : "de",
- log_text,
- state->local_mcc, state->local_mnc,
- peer->cfg->core_mcc, peer->cfg->core_mnc,
- to_bss ? "BSS" : "SGSN");
-
if (state->local_mcc || state->local_mnc) {
enum gbprox_peer_ctr counter =
to_bss ?
@@ -979,7 +998,7 @@
if (v_fixed_shift(&data, &data_len, 6, &value) <= 0)
return 0;
- parse_ctx->raid_enc = value;
+ parse_ctx->old_raid_enc = value;
return 1;
}
@@ -1069,7 +1088,7 @@
if (v_fixed_shift(&data, &data_len, 6, &value) <= 0)
return 0;
- parse_ctx->raid_enc = value;
+ parse_ctx->old_raid_enc = value;
return 1;
}
@@ -1339,14 +1358,18 @@
return have_patched;
if (parse_ctx->raid_enc) {
- /* TODO: BSS->SGSN: Only patch if matches original BSSGP,
- * don't update internal mapping, patch to invalid if P-TMSI
- * unknown. */
gbprox_patch_raid(parse_ctx->raid_enc, peer, parse_ctx->to_bss,
parse_ctx->llc_msg_name);
have_patched = 1;
}
+ if (parse_ctx->old_raid_enc && parse_ctx->old_raid_matches) {
+ /* TODO: Patch to invalid if P-TMSI unknown. */
+ gbprox_patch_raid(parse_ctx->old_raid_enc, peer, parse_ctx->to_bss,
+ parse_ctx->llc_msg_name);
+ have_patched = 1;
+ }
+
if (parse_ctx->apn_ie &&
peer->cfg->core_apn &&
!parse_ctx->to_bss &&
@@ -1399,6 +1422,30 @@
sep = ",";
}
+ if (parse_ctx->bssgp_raid_enc) {
+ struct gprs_ra_id raid;
+ gsm48_parse_ra(&raid, parse_ctx->bssgp_raid_enc);
+ LOGP(DGPRS, LOGL_DEBUG, "%s BSSGP RAID %u-%u-%u-%u", sep,
+ raid.mcc, raid.mnc, raid.lac, raid.rac);
+ sep = ",";
+ }
+
+ if (parse_ctx->raid_enc) {
+ struct gprs_ra_id raid;
+ gsm48_parse_ra(&raid, parse_ctx->raid_enc);
+ LOGP(DGPRS, LOGL_DEBUG, "%s RAID %u-%u-%u-%u", sep,
+ raid.mcc, raid.mnc, raid.lac, raid.rac);
+ sep = ",";
+ }
+
+ if (parse_ctx->old_raid_enc) {
+ struct gprs_ra_id raid;
+ gsm48_parse_ra(&raid, parse_ctx->old_raid_enc);
+ LOGP(DGPRS, LOGL_DEBUG, "%s old RAID %u-%u-%u-%u", sep,
+ raid.mcc, raid.mnc, raid.lac, raid.rac);
+ sep = ",";
+ }
+
if (parse_ctx->ptmsi_enc) {
uint32_t ptmsi = GSM_RESERVED_TMSI;
int ok;
@@ -1840,6 +1887,13 @@
now = time(NULL);
+ if (parse_ctx.bssgp_raid_enc && parse_ctx.old_raid_enc &&
+ memcmp(parse_ctx.bssgp_raid_enc, parse_ctx.old_raid_enc, 6) == 0)
+ parse_ctx.old_raid_matches = 1;
+
+ gbprox_update_current_raid(parse_ctx.bssgp_raid_enc, peer,
+ parse_ctx.llc_msg_name);
+
tlli_info = gbprox_update_state_ul(peer, now, &parse_ctx);
gbprox_patch_bssgp(msg, msgb_bssgph(msg), msgb_bssgp_len(msg),