gbproxy: Use pointer to PTMSI value instead of MI
Currently, ptmsi_enc and new_ptmsi_enc point to the beginning of the
mobile identity. Since all P-TMSI in 04.08 (MM) are encoded this way (1
byte header + 4 byte P-TMSI value). This is different to the P-TMSI
encoding in 08.18 (BSSGP), where the P-TMSI is encoded into 4 byte
without MI header.
This patch changes the code to use pointers to the P-TMSI value,
which is encoded in the same way in both specifications.
Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/gprs/gb_proxy_patch.c b/openbsc/src/gprs/gb_proxy_patch.c
index 5cac8a5..b148094 100644
--- a/openbsc/src/gprs/gb_proxy_patch.c
+++ b/openbsc/src/gprs/gb_proxy_patch.c
@@ -172,7 +172,7 @@
to_bss ?
GBPROX_PEER_CTR_PTMSI_PATCHED_SGSN :
GBPROX_PEER_CTR_PTMSI_PATCHED_BSS;
- memcpy(&ptmsi_be, ptmsi_enc + 1, sizeof(ptmsi_be));
+ memcpy(&ptmsi_be, ptmsi_enc, sizeof(ptmsi_be));
ptmsi = ntohl(ptmsi_be);
if (ptmsi == new_ptmsi)
@@ -184,7 +184,7 @@
log_text, ptmsi, new_ptmsi);
ptmsi_be = htonl(new_ptmsi);
- memcpy(ptmsi_enc + 1, &ptmsi_be, sizeof(ptmsi_be));
+ memcpy(ptmsi_enc, &ptmsi_be, sizeof(ptmsi_be));
rate_ctr_inc(&peer->ctrg->ctr[counter]);
diff --git a/openbsc/src/gprs/gb_proxy_tlli.c b/openbsc/src/gprs/gb_proxy_tlli.c
index 9b337fe..138837e 100644
--- a/openbsc/src/gprs/gb_proxy_tlli.c
+++ b/openbsc/src/gprs/gb_proxy_tlli.c
@@ -481,13 +481,8 @@
if (!link_info && parse_ctx->ptmsi_enc && !parse_ctx->old_raid_is_foreign) {
uint32_t bss_ptmsi;
- if (!gprs_parse_mi_tmsi(parse_ctx->ptmsi_enc, GSM48_TMSI_LEN,
- &bss_ptmsi))
- LOGP(DGPRS, LOGL_ERROR,
- "Failed to parse P-TMSI (TLLI is %08x)\n",
- parse_ctx->tlli);
- else
- link_info = gbproxy_link_info_by_ptmsi(peer, bss_ptmsi);
+ gprs_parse_tmsi(parse_ctx->ptmsi_enc, &bss_ptmsi);
+ link_info = gbproxy_link_info_by_ptmsi(peer, bss_ptmsi);
}
if (link_info)
@@ -563,13 +558,7 @@
* register new TLLI */
uint32_t new_sgsn_ptmsi;
uint32_t new_bss_ptmsi;
- if (!gprs_parse_mi_tmsi(parse_ctx->new_ptmsi_enc, GSM48_TMSI_LEN,
- &new_sgsn_ptmsi)) {
- LOGP(DGPRS, LOGL_ERROR,
- "Failed to parse new TLLI/PTMSI (current is %08x)\n",
- parse_ctx->tlli);
- return link_info;
- }
+ gprs_parse_tmsi(parse_ctx->new_ptmsi_enc, &new_sgsn_ptmsi);
new_bss_ptmsi = gbproxy_make_bss_ptmsi(peer, new_sgsn_ptmsi);
LOGP(DGPRS, LOGL_INFO,
@@ -584,13 +573,7 @@
* TLLI, create a new link_info */
/* TODO: Add a test case for this branch */
uint32_t new_ptmsi;
- if (!gprs_parse_mi_tmsi(parse_ctx->new_ptmsi_enc, GSM48_TMSI_LEN,
- &new_ptmsi)) {
- LOGP(DGPRS, LOGL_ERROR,
- "Failed to parse new PTMSI (TLLI is %08x)\n",
- parse_ctx->tlli);
- return link_info;
- }
+ gprs_parse_tmsi(parse_ctx->new_ptmsi_enc, &new_ptmsi);
LOGP(DGPRS, LOGL_INFO,
"Adding TLLI %08x to list (SGSN, new P-TMSI is %08x)\n",
@@ -620,13 +603,7 @@
return link_info;
/* A new P-TMSI has been signalled in the message */
- if (!gprs_parse_mi_tmsi(parse_ctx->new_ptmsi_enc,
- GSM48_TMSI_LEN, &new_ptmsi)) {
- LOGP(DGPRS, LOGL_ERROR,
- "Failed to parse new PTMSI (TLLI is %08x)\n",
- parse_ctx->tlli);
- return link_info;
- }
+ gprs_parse_tmsi(parse_ctx->new_ptmsi_enc, &new_ptmsi);
LOGP(DGPRS, LOGL_INFO,
"Assigning new P-TMSI %08x\n", new_ptmsi);
/* Setup P-TMSIs */
diff --git a/openbsc/src/gprs/gprs_gb_parse.c b/openbsc/src/gprs/gprs_gb_parse.c
index 87cea1b..1978bd4 100644
--- a/openbsc/src/gprs/gprs_gb_parse.c
+++ b/openbsc/src/gprs/gprs_gb_parse.c
@@ -171,7 +171,7 @@
return 0;
if (gprs_is_mi_tmsi(value, value_len)) {
- parse_ctx->ptmsi_enc = value;
+ parse_ctx->ptmsi_enc = value + 1;
} else if (gprs_is_mi_imsi(value, value_len)) {
parse_ctx->imsi = value;
parse_ctx->imsi_len = value_len;
@@ -215,7 +215,7 @@
if (tlv_match(&data, &data_len, GSM48_IE_GMM_ALLOC_PTMSI,
&value, &value_len) > 0 &&
gprs_is_mi_tmsi(value, value_len))
- parse_ctx->new_ptmsi_enc = value;
+ parse_ctx->new_ptmsi_enc = value + 1;
return 1;
}
@@ -270,7 +270,7 @@
GSM48_IE_GMM_ALLOC_PTMSI, &value, &value_len) > 0)
{
if (gprs_is_mi_tmsi(value, value_len))
- parse_ctx->ptmsi_enc = value;
+ parse_ctx->ptmsi_enc = value + 1;
}
}
@@ -351,7 +351,7 @@
if (tlv_match(&data, &data_len, GSM48_IE_GMM_ALLOC_PTMSI,
&value, &value_len) > 0 &&
gprs_is_mi_tmsi(value, value_len))
- parse_ctx->new_ptmsi_enc = value;
+ parse_ctx->new_ptmsi_enc = value + 1;
return 1;
}
@@ -370,7 +370,7 @@
/* Allocated P-TMSI */
if (lv_shift(&data, &data_len, &value, &value_len) > 0 &&
gprs_is_mi_tmsi(value, value_len))
- parse_ctx->new_ptmsi_enc = value;
+ parse_ctx->new_ptmsi_enc = value + 1;
if (v_fixed_shift(&data, &data_len, 6, &value) <= 0)
return 0;
@@ -395,7 +395,7 @@
return 0;
if (gprs_is_mi_tmsi(value, value_len)) {
- parse_ctx->ptmsi_enc = value;
+ parse_ctx->ptmsi_enc = value + 1;
} else if (gprs_is_mi_imsi(value, value_len)) {
parse_ctx->imsi = value;
parse_ctx->imsi_len = value_len;
@@ -680,20 +680,15 @@
if (parse_ctx->ptmsi_enc) {
uint32_t ptmsi = GSM_RESERVED_TMSI;
- int ok;
- ok = gprs_parse_mi_tmsi(parse_ctx->ptmsi_enc, GSM48_TMSI_LEN, &ptmsi);
- LOGPC(DGPRS, LOGL_DEBUG, "%s PTMSI %08x%s",
- sep, ptmsi, ok ? "" : " (parse error)");
+ gprs_parse_tmsi(parse_ctx->ptmsi_enc, &ptmsi);
+ LOGPC(DGPRS, LOGL_DEBUG, "%s PTMSI %08x", sep, ptmsi);
sep = ",";
}
if (parse_ctx->new_ptmsi_enc) {
uint32_t new_ptmsi = GSM_RESERVED_TMSI;
- int ok;
- ok = gprs_parse_mi_tmsi(parse_ctx->new_ptmsi_enc, GSM48_TMSI_LEN,
- &new_ptmsi);
- LOGPC(DGPRS, LOGL_DEBUG, "%s new PTMSI %08x%s",
- sep, new_ptmsi, ok ? "" : " (parse error)");
+ gprs_parse_tmsi(parse_ctx->new_ptmsi_enc, &new_ptmsi);
+ LOGPC(DGPRS, LOGL_DEBUG, "%s new PTMSI %08x", sep, new_ptmsi);
sep = ",";
}
diff --git a/openbsc/src/gprs/gprs_utils.c b/openbsc/src/gprs/gprs_utils.c
index c620454..0cf8e4f 100644
--- a/openbsc/src/gprs/gprs_utils.c
+++ b/openbsc/src/gprs/gprs_utils.c
@@ -209,3 +209,11 @@
return 1;
}
+void gprs_parse_tmsi(const uint8_t *value, uint32_t *tmsi)
+{
+ uint32_t tmsi_be;
+
+ memcpy(&tmsi_be, value, sizeof(tmsi_be));
+
+ *tmsi = ntohl(tmsi_be);
+}