cellular-infrastructure
/
osmo-sgsn
mirror of https://gerrit.osmocom.org/osmo-sgsn
9
0
Fork 0
Code Issues Releases Wiki Activity

gbproxy: Avoid depending on any of the SGSN code 

The last remaining functin of the SGSN code base we used was
gprs_gb_parse_tlli().

Let's simply copy this function over and become  self-contained.

This would allow migrating osmo-gbproxy to a separate repository.

Change-Id: I6f3f86581b47ad71a3d97f07611a2e2709876d69
This commit is contained in:
Harald Welte 2021-01-28 19:13:19 +01:00
parent 21afdf9a32
commit e0876bda26
2 changed files with 41 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
src/gbproxy/Makefile.am
View File

@ -30,10 +30,6 @@ osmo_gbproxy_SOURCES = \
gb_proxy_peer.c \
$(NULL)
osmo_gbproxy_LDADD = \
$(top_builddir)/src/gprs/gprs_gb_parse.o \
$(top_builddir)/src/gprs/gprs_llc_parse.o \
$(top_builddir)/src/gprs/crc24.o \
$(top_builddir)/src/gprs/gprs_utils.o \
$(LIBOSMOCORE_LIBS) \
$(LIBOSMOGSM_LIBS) \
$(LIBOSMOVTY_LIBS) \

41
src/gbproxy/gb_proxy.c
View File

@ -136,6 +136,47 @@ static int gbprox_relay2sgsn(struct gbproxy_config *cfg, struct msgb *old_msg,
}
#endif
/*! Determine the TLLI from the given BSSGP message.
* \param[in] bssgp pointer to start of BSSGP header
* \param[in] bssgp_len length of BSSGP message in octets
* \param[out] tlli TLLI (if any) in host byte order
* \returns 1 if TLLI found; 0 if none found; negative on parse error */
int gprs_gb_parse_tlli(const uint8_t *bssgp, size_t bssgp_len, uint32_t *tlli)
{
const struct bssgp_normal_hdr *bgph;
uint8_t pdu_type;
if (bssgp_len < sizeof(struct bssgp_normal_hdr))
return -EINVAL;
bgph = (struct bssgp_normal_hdr *)bssgp;
pdu_type = bgph->pdu_type;
if (pdu_type == BSSGP_PDUT_UL_UNITDATA ||
pdu_type == BSSGP_PDUT_DL_UNITDATA) {
const struct bssgp_ud_hdr *budh = (struct bssgp_ud_hdr *)bssgp;
if (bssgp_len < sizeof(struct bssgp_ud_hdr))
return -EINVAL;
*tlli = osmo_load32be((const uint8_t *)&budh->tlli);
return 1;
} else {
const uint8_t *data = bgph->data;
size_t data_len = bssgp_len - sizeof(*bgph);
struct tlv_parsed tp;
if (bssgp_tlv_parse(&tp, data, data_len) < 0)
return -EINVAL;
if (TLVP_PRESENT(&tp, BSSGP_IE_TLLI)) {
*tlli = osmo_load32be(TLVP_VAL(&tp, BSSGP_IE_TLLI));
return 1;
}
}
/* No TLLI present in message */
return 0;
}
/* feed a message down the NSE */
static int gbprox_relay2nse(struct msgb *old_msg, struct gbproxy_nse *nse,
uint16_t ns_bvci)