on HNB Register, discard old HNB with same id, allow new connection

Change-Id: I6b04398296fdd9657a733984f28c2ef4188861ab
This commit is contained in:
Neels Hofmeyr 2023-02-11 03:11:41 +01:00
parent a3c7f750a2
commit c62b45d589
1 changed files with 19 additions and 34 deletions

View File

@ -49,6 +49,7 @@ static int hnbgw_hnbap_tx(struct hnb_context *ctx, struct msgb *msg)
return 0;
}
#if 0
static int hnbgw_tx_hnb_register_rej(struct hnb_context *ctx)
{
HNBAP_HNBRegisterReject_t reject_out;
@ -90,6 +91,7 @@ static int hnbgw_tx_hnb_register_rej(struct hnb_context *ctx)
return 0;
}
#endif
static int hnbgw_tx_hnb_register_acc(struct hnb_context *ctx)
{
@ -428,41 +430,24 @@ static int hnbgw_rx_hnb_register_req(struct hnb_context *ctx, ANY_t *in)
ctx->id.mcc = plmn.mcc;
ctx->id.mnc = plmn.mnc;
/* Guard against duplicate entries of HNB with the same LAC,SAC,RAC,CID,MCC,MNC identity */
llist_for_each_entry_safe(hnb, tmp, &ctx->gw->hnb_list, list) {
if (hnb->hnb_registered && ctx != hnb && memcmp(&ctx->id, &hnb->id, sizeof(ctx->id)) == 0) {
/* If it's coming from the same remote IP addr+port, then it must be our internal
* fault (bug), and we release the old context to keep going... */
struct osmo_fd *other_fd = osmo_stream_srv_get_ofd(hnb->conn);
struct osmo_sockaddr other_osa = {};
struct osmo_sockaddr cur_osa = {};
socklen_t len = sizeof(other_osa);
if (getpeername(other_fd->fd, &other_osa.u.sa, &len) < 0) {
LOGHNB(ctx, DHNBAP, LOGL_ERROR, "BUG! Found old registered HNB with invalid socket, releasing it\n");
hnb_context_release(hnb);
if (hnb == ctx)
continue;
}
len = sizeof(cur_osa);
if (getpeername(ofd->fd, &cur_osa.u.sa, &len) < 0) {
LOGHNB(ctx, DHNBAP, LOGL_ERROR, "Error getpeername(): %s\n", strerror(errno));
if (osmo_sockaddr_cmp(&cur_osa, &other_osa) == 0) {
LOGHNB(ctx, DHNBAP, LOGL_ERROR, "BUG! Found old registered HNB with same remote address, releasing it\n");
hnb_context_release(hnb);
if (!hnb->hnb_registered)
continue;
}
} else if (osmo_sockaddr_cmp(&cur_osa, &other_osa) == 0) {
LOGHNB(ctx, DHNBAP, LOGL_ERROR, "BUG! Found old registered HNB with same remote address, releasing it\n");
hnb_context_release(hnb);
if (memcmp(&ctx->id, &hnb->id, sizeof(ctx->id)))
continue;
} /* else: addresses are different, we continue below */
/* If new conn registering same HNB is from anoter remote addr+port, let's reject it to avoid
* misconfigurations or someone trying to impersonate an already working HNB: */
LOGHNB(ctx, DHNBAP, LOGL_ERROR, "rejecting HNB-REGISTER-REQ with duplicate cell identity "
"MCC=%u,MNC=%u,LAC=%u,RAC=%u,SAC=%u,CID=%u from %s\n",
/* There is another hnb_context with the same id.
* This can be misconfiguration -- the user must make sure to avoid two HNB with the same id.
* Or this is the same HNB re-connecting on a new conn, before osmo-hnbgw noticed that the HNB has gone
* down.
* Allow the new HNB connection, discard the old hnb_context. */
LOGHNB(ctx, DHNBAP, LOGL_ERROR, "A HNB with the same cell identity already exists, discarding old HNB"
" context, in favor of this new HNB-REGISTER-REQ for"
" MCC=%u,MNC=%u,LAC=%u,RAC=%u,SAC=%u,CID=%u from %s\n",
ctx->id.mcc, ctx->id.mnc, ctx->id.lac, ctx->id.rac, ctx->id.sac, ctx->id.cid, name);
hnbap_free_hnbregisterrequesties(&ies);
return hnbgw_tx_hnb_register_rej(ctx);
}
hnb_context_release(hnb);
}
LOGHNB(ctx, DHNBAP, LOGL_DEBUG, "HNB-REGISTER-REQ %s MCC=%u,MNC=%u,LAC=%u,RAC=%u,SAC=%u,CID=%u from %s%s\n",