diff options
author | Philipp <pmaier@sysmocom.de> | 2016-12-22 14:15:20 +0100 |
---|---|---|
committer | Philipp <pmaier@sysmocom.de> | 2016-12-23 11:19:15 +0100 |
commit | db142dc59dc8d79d8ee608c9165bc865d240b97d (patch) | |
tree | a4c1ec7fdece679b7dd252ac321b28c60e3492d2 /openbsc/tests/sndcp_xid | |
parent | a191dcd8f01767b266b85578d0fb445d864dfabd (diff) |
sndcp: Allow empty SNDCP-XID indications
In some rare cases the modem might send a xid indication that does
not contain anything except the version number field. The sgsn
ignors such SNDCP-XID indications by stripping the entire field
from the response. We found a modem in the wild that started to
act problematic when the empty SNDCP-XID was missing in the
response. This patch changes the XID negotiation behaviour in
a way that if a modem should send empty SNDCP-XID indications,
the reply will also contain an empty SNDCP-XID indication. Apart
from that the SNDCP-XID version number is now parsed and echoed
in the response. This ensures that we always reply with the version
number that the modem expects. (The version was 0 in all cases we
observed so far)
Change-Id: I097a770cb4907418f53e620a051ebb8cd110c5f2
Related: OS#1794
Diffstat (limited to 'openbsc/tests/sndcp_xid')
-rw-r--r-- | openbsc/tests/sndcp_xid/sndcp_xid_test.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/openbsc/tests/sndcp_xid/sndcp_xid_test.c b/openbsc/tests/sndcp_xid/sndcp_xid_test.c index 3a3361970..151dd2bb5 100644 --- a/openbsc/tests/sndcp_xid/sndcp_xid_test.c +++ b/openbsc/tests/sndcp_xid/sndcp_xid_test.c @@ -47,13 +47,14 @@ static void test_xid_decode_realworld(const void *ctx) uint8_t xid_r[512]; /* Parse and show contained comp fields */ - comp_fields = gprs_sndcp_parse_xid(ctx, xid, sizeof(xid), NULL); + comp_fields = gprs_sndcp_parse_xid(NULL, ctx, xid, sizeof(xid), NULL); OSMO_ASSERT(comp_fields); printf("Decoded:\n"); gprs_sndcp_dump_comp_fields(comp_fields, DSNDCP); /* Encode comp-fields again */ - rc = gprs_sndcp_compile_xid(xid_r,sizeof(xid_r), comp_fields); + rc = gprs_sndcp_compile_xid(xid_r,sizeof(xid_r), comp_fields, + DEFAULT_SNDCP_VERSION); printf("Result length=%i\n",rc); printf("Encoded: %s\n", osmo_hexdump_nospc(xid, sizeof(xid))); printf("Rencoded: %s\n", osmo_hexdump_nospc(xid_r, rc)); @@ -226,13 +227,14 @@ static void test_xid_encode_decode(const void *ctx) gprs_sndcp_dump_comp_fields(&comp_fields, DSNDCP); /* Encode SNDCP-XID fields */ - rc = gprs_sndcp_compile_xid(xid, xid_len, &comp_fields); + rc = gprs_sndcp_compile_xid(xid, xid_len, &comp_fields, + DEFAULT_SNDCP_VERSION); OSMO_ASSERT(rc > 0); printf("Encoded: %s (%i bytes)\n", osmo_hexdump_nospc(xid, rc), rc); /* Parse and show contained comp fields */ - comp_fields_dec = gprs_sndcp_parse_xid(ctx, xid, rc, NULL); + comp_fields_dec = gprs_sndcp_parse_xid(NULL, ctx, xid, rc, NULL); OSMO_ASSERT(comp_fields_dec); printf("Decoded:\n"); |