ranap_rab_ass: add function to check if RAB is in FailureList

A RANAP RAB-AssignmentResponse may contain a FailedList. In order to
detect that a RAB Assignment failed at the HNB we need to be able to
check if the RAB we are dealing with is contained an such a FailedList.

Change-Id: I4319f7caa45ea758ccd792cc8570521df075cf45
Related: OS#5152
This commit is contained in:
Philipp Maier 2022-02-10 18:16:28 +01:00
parent 0c465b0f68
commit efe4850e75
4 changed files with 102 additions and 2 deletions

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@ -14,3 +14,5 @@ int ranap_rab_ass_req_ies_replace_inet_addr(RANAP_RAB_AssignmentRequestIEs_t *ie
uint8_t rab_id);
int ranap_rab_ass_resp_ies_replace_inet_addr(RANAP_RAB_AssignmentResponseIEs_t *ies, struct osmo_sockaddr *addr,
uint8_t rab_id);
bool ranap_rab_ass_resp_ies_check_failure(RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t rab_id);

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@ -141,8 +141,7 @@ static RANAP_IE_t *setup_or_modif_item_from_rab_ass_resp(const RANAP_RAB_Assignm
{
/* Make sure we indeed deal with a setup-or-modified list */
if (!(ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_SETUPORMODIFIEDLIST_PRESENT)) {
RANAP_DEBUG
("Decoding failed, the RANAP RAB AssignmentResponse did not contain a setup-or-modified list!\n");
RANAP_DEBUG("RANAP RAB AssignmentResponse did not contain a setup-or-modified list!\n");
return NULL;
}
@ -153,6 +152,23 @@ static RANAP_IE_t *setup_or_modif_item_from_rab_ass_resp(const RANAP_RAB_Assignm
return ies->raB_SetupOrModifiedList.raB_SetupOrModifiedList_ies.list.array[index];
}
/* Pick the indexed item from the RAB failed list and return a pointer to it */
static RANAP_IE_t *failed_list_item_from_rab_ass_resp(const RANAP_RAB_AssignmentResponseIEs_t *ies,
unsigned int index)
{
/* Make sure we indeed deal with a failed list */
if (!(ies->presenceMask & RAB_ASSIGNMENTRESPONSEIES_RANAP_RAB_FAILEDLIST_PRESENT)) {
RANAP_DEBUG("RANAP RAB AssignmentResponse did not contain a failed list!\n");
return NULL;
}
/* Detect the end of the list */
if (index >= ies->raB_FailedList.raB_FailedList_ies.list.count)
return NULL;
return ies->raB_FailedList.raB_FailedList_ies.list.array[index];
}
/* find the RAB specified by rab_id in ies and when found, decode the result into items_ies */
static int decode_rab_smditms_from_resp_ies(RANAP_RAB_SetupOrModifiedItemIEs_t *items_ies,
RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t rab_id)
@ -184,6 +200,37 @@ static int decode_rab_smditms_from_resp_ies(RANAP_RAB_SetupOrModifiedItemIEs_t *
}
}
/* See comment above decode_rab_smditms_from_resp_ies() */
static int decode_rab_flitms_from_resp_ies(RANAP_RAB_FailedItemIEs_t *items_ies,
RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t rab_id)
{
RANAP_IE_t *failed_list_ie;
RANAP_RAB_FailedItem_t *rab_failed_item;
int rc;
uint8_t rab_id_decoded;
unsigned int index = 0;
while (1) {
failed_list_ie = failed_list_item_from_rab_ass_resp(ies, index);
if (!failed_list_ie)
return -EINVAL;
rc = ranap_decode_rab_faileditemies_fromlist(items_ies, &failed_list_ie->value);
if (rc < 0)
return -EINVAL;
rab_failed_item = &items_ies->raB_FailedItem;
/* The RAB-ID is defined as a bitstring with a size of 8 (1 byte),
* See also RANAP-IEs.asn, RAB-ID ::= BIT STRING (SIZE (8)) */
rab_id_decoded = rab_failed_item->rAB_ID.buf[0];
if (rab_id_decoded == rab_id)
return index;
ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_FailedItem, items_ies);
index++;
}
}
/* find the RAB specified by rab_id in ies and when found, decode the result into item */
static int decode_rab_smditms_from_req_ies(RANAP_RAB_SetupOrModifyItemFirst_t *item,
RANAP_RAB_AssignmentRequestIEs_t *ies, uint8_t rab_id)
@ -477,3 +524,25 @@ error:
return rc;
}
/*! Check if a specific RAB is present in an RAB-Failed-Item-List inside RANAP_RAB_AssignmentResponseIEs.
* \ptmap[in] ies user provided memory with RANAP_RAB_AssignmentResponseIEs.
* \ptmap[in] rab_id expected rab id to look for.
* \returns true when RAB could be identified as failed; false otherwise */
bool ranap_rab_ass_resp_ies_check_failure(RANAP_RAB_AssignmentResponseIEs_t *ies, uint8_t rab_id)
{
RANAP_RAB_FailedItemIEs_t _rab_failed_items_ies;
RANAP_RAB_FailedItemIEs_t *rab_failed_items_ies = &_rab_failed_items_ies;
int rc;
bool result = true;
/* If we can get a failed item for the specified RAB ID, then we know that the
* HNB reported the RAB Assignment as failed */
rc = decode_rab_flitms_from_resp_ies(rab_failed_items_ies, ies, rab_id);
if (rc < 0)
result = false;
ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_RANAP_RAB_FailedItem, rab_failed_items_ies);
return result;
}

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@ -269,6 +269,32 @@ void test_ranap_rab_ass_resp_replace_inet_addr(void)
ranap_cn_rx_co_free(&message);
}
void test_ranap_rab_ass_resp_ies_check_failure(void)
{
int rc;
ranap_message message;
bool rab_failed_at_hnb;
uint8_t testvec[] = {
0x60, 0x00, 0x00, 0x11, 0x00, 0x00, 0x01, 0x00,
0x23, 0x40, 0x0a, 0x00, 0x00, 0x01, 0x00, 0x22,
0x40, 0x03, 0x05, 0xd0, 0x00
};
rc = ranap_cn_rx_co_decode(talloc_asn1_ctx, &message, testvec, sizeof(testvec));
OSMO_ASSERT(rc == 0);
rab_failed_at_hnb =
ranap_rab_ass_resp_ies_check_failure(&message.msg.raB_AssignmentResponseIEs, 23);
printf("ranap_rab_ass_resp_ies_check_failure rab_failed_at_hnb=%u (RAB ID 23)\n", rab_failed_at_hnb);
rab_failed_at_hnb =
ranap_rab_ass_resp_ies_check_failure(&message.msg.raB_AssignmentResponseIEs, 44);
printf("ranap_rab_ass_resp_ies_check_failure rab_failed_at_hnb=%u (RAB ID 44, which is not in the message)\n",
rab_failed_at_hnb);
ranap_cn_rx_co_free(&message);
}
static const struct log_info_cat log_cat[] = {
[DRANAP] = {
.name = "RANAP", .loglevel = LOGL_DEBUG, .enabled = 1,
@ -329,6 +355,7 @@ int main(int argc, char **argv)
test_ranap_rab_ass_resp_extract_inet_addr();
test_ranap_rab_ass_req_replace_inet_addr();
test_ranap_rab_ass_resp_replace_inet_addr();
test_ranap_rab_ass_resp_ies_check_failure();
test_cleanup();
return 0;

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@ -14,3 +14,5 @@ after: addr=1.2.3.4, port=1234, rab_id=39
before: addr=10.9.1.164, port=1034
ranap_rab_ass_resp_replace_inet_addr rc=0
after: addr=1.2.3.4, port=1234
ranap_rab_ass_resp_ies_check_failure rab_failed_at_hnb=1 (RAB ID 23)
ranap_rab_ass_resp_ies_check_failure rab_failed_at_hnb=0 (RAB ID 44, which is not in the message)