gprs: Move TLV parser functions to gprs_utils.c and rename them
Currently the parser functions for single information elements are
defined within gprs_gb_parse.c and not exported explicitely. In
addition they are named like libosmocore's TLV parser functions and
do not have a proper name prefix. Since it is planned to use them for
other protocols, they need to be globally accessible.
This patch moves them to gprs_utils.c and renames them.
The new names are:
lv_shift -> gprs_shift_lv
v_fixed_shift -> gprs_shift_v_fixed
lv_shift -> gprs_shift_lv
v_fixed_shift -> gprs_shift_v_fixed
In the long term, these functions should be moved to libosmocore (and
renamed again).
Sponsored-by: On-Waves ehf
diff --git a/openbsc/src/gprs/gprs_gb_parse.c b/openbsc/src/gprs/gprs_gb_parse.c
index 6c6371c..6096854 100644
--- a/openbsc/src/gprs/gprs_gb_parse.c
+++ b/openbsc/src/gprs/gprs_gb_parse.c
@@ -29,122 +29,6 @@
#include <osmocom/gprs/gprs_bssgp.h>
-/* TODO: Move shift functions to libosmocore */
-
-int v_fixed_shift(uint8_t **data, size_t *data_len,
- size_t len, uint8_t **value)
-{
- if (len > *data_len)
- goto fail;
-
- if (value)
- *value = *data;
-
- *data += len;
- *data_len -= len;
-
- return len;
-
-fail:
- *data += *data_len;
- *data_len = 0;
- return -1;
-}
-
-int tv_fixed_match(uint8_t **data, size_t *data_len,
- uint8_t tag, size_t len,
- uint8_t **value)
-{
- size_t ie_len;
-
- if (*data_len == 0)
- goto fail;
-
- if ((*data)[0] != tag)
- return 0;
-
- if (len > *data_len - 1)
- goto fail;
-
- if (value)
- *value = *data + 1;
-
- ie_len = len + 1;
- *data += ie_len;
- *data_len -= ie_len;
-
- return ie_len;
-
-fail:
- *data += *data_len;
- *data_len = 0;
- return -1;
-}
-
-int tlv_match(uint8_t **data, size_t *data_len,
- uint8_t tag, uint8_t **value, size_t *value_len)
-{
- size_t len;
- size_t ie_len;
-
- if (*data_len < 2)
- goto fail;
-
- if ((*data)[0] != tag)
- return 0;
-
- len = (*data)[1];
- if (len > *data_len - 2)
- goto fail;
-
- if (value)
- *value = *data + 2;
- if (value_len)
- *value_len = len;
-
- ie_len = len + 2;
-
- *data += ie_len;
- *data_len -= ie_len;
-
- return ie_len;
-
-fail:
- *data += *data_len;
- *data_len = 0;
- return -1;
-}
-
-int lv_shift(uint8_t **data, size_t *data_len,
- uint8_t **value, size_t *value_len)
-{
- size_t len;
- size_t ie_len;
-
- if (*data_len < 1)
- goto fail;
-
- len = (*data)[0];
- if (len > *data_len - 1)
- goto fail;
-
- if (value)
- *value = *data + 1;
- if (value_len)
- *value_len = len;
-
- ie_len = len + 1;
- *data += ie_len;
- *data_len -= ie_len;
-
- return ie_len;
-
-fail:
- *data += *data_len;
- *data_len = 0;
- return -1;
-}
-
static int gprs_gb_parse_gmm_attach_req(uint8_t *data, size_t data_len,
struct gprs_gb_parse_context *parse_ctx)
{
@@ -154,7 +38,7 @@
parse_ctx->llc_msg_name = "ATTACH_REQ";
/* Skip MS network capability */
- if (lv_shift(&data, &data_len, NULL, &value_len) <= 0 ||
+ if (gprs_shift_lv(&data, &data_len, NULL, &value_len) <= 0 ||
value_len < 1 || value_len > 8)
/* invalid */
return 0;
@@ -162,10 +46,10 @@
/* Skip Attach type */
/* Skip Ciphering key sequence number */
/* Skip DRX parameter */
- v_fixed_shift(&data, &data_len, 3, NULL);
+ gprs_shift_v_fixed(&data, &data_len, 3, NULL);
/* Get Mobile identity */
- if (lv_shift(&data, &data_len, &value, &value_len) <= 0 ||
+ if (gprs_shift_lv(&data, &data_len, &value, &value_len) <= 0 ||
value_len < 5 || value_len > 8)
/* invalid */
return 0;
@@ -177,7 +61,7 @@
parse_ctx->imsi_len = value_len;
}
- if (v_fixed_shift(&data, &data_len, 6, &value) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, 6, &value) <= 0)
return 0;
parse_ctx->old_raid_enc = value;
@@ -198,21 +82,21 @@
/* Skip Periodic RA update timer */
/* Skip Radio priority for SMS */
/* Skip Spare half octet */
- v_fixed_shift(&data, &data_len, 3, NULL);
+ gprs_shift_v_fixed(&data, &data_len, 3, NULL);
- if (v_fixed_shift(&data, &data_len, 6, &value) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, 6, &value) <= 0)
return 0;
parse_ctx->raid_enc = value;
/* Skip P-TMSI signature (P-TMSI signature, opt, TV, length 4) */
- tv_fixed_match(&data, &data_len, GSM48_IE_GMM_PTMSI_SIG, 3, NULL);
+ gprs_match_tv_fixed(&data, &data_len, GSM48_IE_GMM_PTMSI_SIG, 3, NULL);
/* Skip Negotiated READY timer value (GPRS timer, opt, TV, length 2) */
- tv_fixed_match(&data, &data_len, GSM48_IE_GMM_TIMER_READY, 1, NULL);
+ gprs_match_tv_fixed(&data, &data_len, GSM48_IE_GMM_TIMER_READY, 1, NULL);
/* Allocated P-TMSI (Mobile identity, opt, TLV, length 7) */
- if (tlv_match(&data, &data_len, GSM48_IE_GMM_ALLOC_PTMSI,
+ if (gprs_match_tlv(&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 + 1;
@@ -227,7 +111,7 @@
parse_ctx->llc_msg_name = "ATTACH_REJ";
/* GMM cause */
- if (v_fixed_shift(&data, &data_len, 1, &value) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, 1, &value) <= 0)
return 0;
parse_ctx->invalidate_tlli = 1;
@@ -248,7 +132,7 @@
/* Skip spare half octet */
/* Get Detach type */
- if (v_fixed_shift(&data, &data_len, 1, &value) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, 1, &value) <= 0)
/* invalid */
return 0;
@@ -266,7 +150,7 @@
parse_ctx->invalidate_tlli = 1;
/* Get P-TMSI (Mobile identity), see GSM 24.008, 9.4.5.2 */
- if (tlv_match(&data, &data_len,
+ if (gprs_match_tlv(&data, &data_len,
GSM48_IE_GMM_ALLOC_PTMSI, &value, &value_len) > 0)
{
if (gprs_is_mi_tmsi(value, value_len))
@@ -286,9 +170,9 @@
/* Skip Update type */
/* Skip GPRS ciphering key sequence number */
- v_fixed_shift(&data, &data_len, 1, NULL);
+ gprs_shift_v_fixed(&data, &data_len, 1, NULL);
- if (v_fixed_shift(&data, &data_len, 6, &value) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, 6, &value) <= 0)
return 0;
parse_ctx->old_raid_enc = value;
@@ -306,14 +190,14 @@
parse_ctx->llc_msg_name = "RA_UPD_REJ";
/* GMM cause */
- if (v_fixed_shift(&data, &data_len, 1, &value) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, 1, &value) <= 0)
return 0;
cause = value[0];
/* Force to standby, 1/2 */
/* spare bits, 1/2 */
- if (v_fixed_shift(&data, &data_len, 1, &value) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, 1, &value) <= 0)
return 0;
force_standby = (value[0] & 0x07) == 0x01;
@@ -337,18 +221,18 @@
/* Skip Force to standby */
/* Skip Update result */
/* Skip Periodic RA update timer */
- v_fixed_shift(&data, &data_len, 2, NULL);
+ gprs_shift_v_fixed(&data, &data_len, 2, NULL);
- if (v_fixed_shift(&data, &data_len, 6, &value) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, 6, &value) <= 0)
return 0;
parse_ctx->raid_enc = value;
/* Skip P-TMSI signature (P-TMSI signature, opt, TV, length 4) */
- tv_fixed_match(&data, &data_len, GSM48_IE_GMM_PTMSI_SIG, 3, NULL);
+ gprs_match_tv_fixed(&data, &data_len, GSM48_IE_GMM_PTMSI_SIG, 3, NULL);
/* Allocated P-TMSI (Mobile identity, opt, TLV, length 7) */
- if (tlv_match(&data, &data_len, GSM48_IE_GMM_ALLOC_PTMSI,
+ if (gprs_match_tlv(&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 + 1;
@@ -368,11 +252,11 @@
"Got P-TMSI Reallocation Command which is not covered by unit tests yet.\n");
/* Allocated P-TMSI */
- if (lv_shift(&data, &data_len, &value, &value_len) > 0 &&
+ if (gprs_shift_lv(&data, &data_len, &value, &value_len) > 0 &&
gprs_is_mi_tmsi(value, value_len))
parse_ctx->new_ptmsi_enc = value + 1;
- if (v_fixed_shift(&data, &data_len, 6, &value) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, 6, &value) <= 0)
return 0;
parse_ctx->raid_enc = value;
@@ -389,7 +273,7 @@
parse_ctx->llc_msg_name = "ID_RESP";
/* Mobile identity, Mobile identity 10.5.1.4, M LV 2-10 */
- if (lv_shift(&data, &data_len, &value, &value_len) <= 0 ||
+ if (gprs_shift_lv(&data, &data_len, &value, &value_len) <= 0 ||
value_len < 1 || value_len > 9)
/* invalid */
return 0;
@@ -415,22 +299,22 @@
/* Skip Requested NSAPI */
/* Skip Requested LLC SAPI */
- v_fixed_shift(&data, &data_len, 2, NULL);
+ gprs_shift_v_fixed(&data, &data_len, 2, NULL);
/* Skip Requested QoS (support 04.08 and 24.008) */
- if (lv_shift(&data, &data_len, NULL, &value_len) <= 0 ||
+ if (gprs_shift_lv(&data, &data_len, NULL, &value_len) <= 0 ||
value_len < 4 || value_len > 14)
/* invalid */
return 0;
/* Skip Requested PDP address */
- if (lv_shift(&data, &data_len, NULL, &value_len) <= 0 ||
+ if (gprs_shift_lv(&data, &data_len, NULL, &value_len) <= 0 ||
value_len < 2 || value_len > 18)
/* invalid */
return 0;
/* Access point name */
- old_len = tlv_match(&data, &data_len,
+ old_len = gprs_match_tlv(&data, &data_len,
GSM48_IE_GSM_APN, &value, &value_len);
if (old_len > 0 && value_len >=1 && value_len <= 100) {
@@ -446,7 +330,7 @@
{
struct gsm48_hdr *g48h;
- if (v_fixed_shift(&data, &data_len, sizeof(*g48h), (uint8_t **)&g48h) <= 0)
+ if (gprs_shift_v_fixed(&data, &data_len, sizeof(*g48h), (uint8_t **)&g48h) <= 0)
return 0;
parse_ctx->g48_hdr = g48h;
diff --git a/openbsc/src/gprs/gprs_utils.c b/openbsc/src/gprs/gprs_utils.c
index 0cf8e4f..cec07d7 100644
--- a/openbsc/src/gprs/gprs_utils.c
+++ b/openbsc/src/gprs/gprs_utils.c
@@ -217,3 +217,120 @@
*tmsi = ntohl(tmsi_be);
}
+
+/* TODO: Move shift functions to libosmocore */
+
+int gprs_shift_v_fixed(uint8_t **data, size_t *data_len,
+ size_t len, uint8_t **value)
+{
+ if (len > *data_len)
+ goto fail;
+
+ if (value)
+ *value = *data;
+
+ *data += len;
+ *data_len -= len;
+
+ return len;
+
+fail:
+ *data += *data_len;
+ *data_len = 0;
+ return -1;
+}
+
+int gprs_match_tv_fixed(uint8_t **data, size_t *data_len,
+ uint8_t tag, size_t len,
+ uint8_t **value)
+{
+ size_t ie_len;
+
+ if (*data_len == 0)
+ goto fail;
+
+ if ((*data)[0] != tag)
+ return 0;
+
+ if (len > *data_len - 1)
+ goto fail;
+
+ if (value)
+ *value = *data + 1;
+
+ ie_len = len + 1;
+ *data += ie_len;
+ *data_len -= ie_len;
+
+ return ie_len;
+
+fail:
+ *data += *data_len;
+ *data_len = 0;
+ return -1;
+}
+
+int gprs_match_tlv(uint8_t **data, size_t *data_len,
+ uint8_t tag, uint8_t **value, size_t *value_len)
+{
+ size_t len;
+ size_t ie_len;
+
+ if (*data_len < 2)
+ goto fail;
+
+ if ((*data)[0] != tag)
+ return 0;
+
+ len = (*data)[1];
+ if (len > *data_len - 2)
+ goto fail;
+
+ if (value)
+ *value = *data + 2;
+ if (value_len)
+ *value_len = len;
+
+ ie_len = len + 2;
+
+ *data += ie_len;
+ *data_len -= ie_len;
+
+ return ie_len;
+
+fail:
+ *data += *data_len;
+ *data_len = 0;
+ return -1;
+}
+
+int gprs_shift_lv(uint8_t **data, size_t *data_len,
+ uint8_t **value, size_t *value_len)
+{
+ size_t len;
+ size_t ie_len;
+
+ if (*data_len < 1)
+ goto fail;
+
+ len = (*data)[0];
+ if (len > *data_len - 1)
+ goto fail;
+
+ if (value)
+ *value = *data + 1;
+ if (value_len)
+ *value_len = len;
+
+ ie_len = len + 1;
+ *data += ie_len;
+ *data_len -= ie_len;
+
+ return ie_len;
+
+fail:
+ *data += *data_len;
+ *data_len = 0;
+ return -1;
+}
+