/* Copyright 2019 by sysmocom s.f.m.c. GmbH * * All Rights Reserved * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see . * */ #include #include #include #include #include #include #include #include #include #include #include static LLIST_HEAD(remote_hlrs); static void remote_hlr_err_reply(struct remote_hlr *rh, const struct osmo_gsup_message *gsup_orig, enum gsm48_gmm_cause cause) { struct osmo_gsup_message gsup_reply; /* No need to answer if we couldn't parse an ERROR message type, only REQUESTs need an error reply. */ if (!OSMO_GSUP_IS_MSGT_REQUEST(gsup_orig->message_type)) return; gsup_reply = (struct osmo_gsup_message){ .cause = cause, .message_type = OSMO_GSUP_TO_MSGT_ERROR(gsup_orig->message_type), .message_class = gsup_orig->message_class, /* RP-Message-Reference is mandatory for SM Service */ .sm_rp_mr = gsup_orig->sm_rp_mr, }; OSMO_STRLCPY_ARRAY(gsup_reply.imsi, gsup_orig->imsi); /* For SS/USSD, it's important to keep both session state and ID IEs */ if (gsup_orig->session_state != OSMO_GSUP_SESSION_STATE_NONE) { gsup_reply.session_state = OSMO_GSUP_SESSION_STATE_END; gsup_reply.session_id = gsup_orig->session_id; } if (osmo_gsup_client_enc_send(rh->gsupc, &gsup_reply)) LOGP(DLGSUP, LOGL_ERROR, "Failed to send Error reply (imsi=%s)\n", osmo_quote_str(gsup_orig->imsi, -1)); } /* We are receiving a GSUP message from a remote HLR to go back to a local MSC. * The local MSC shall be indicated by gsup.destination_name. */ static int remote_hlr_rx(struct osmo_gsup_client *gsupc, struct msgb *msg) { struct remote_hlr *rh = gsupc->data; struct proxy_subscr proxy_subscr; struct osmo_gsup_message gsup; int rc; rc = osmo_gsup_decode(msgb_l2(msg), msgb_l2len(msg), &gsup); if (rc < 0) { LOG_REMOTE_HLR(rh, LOGL_ERROR, "Failed to decode GSUP message: '%s' (%d) [ %s]\n", get_value_string(gsm48_gmm_cause_names, -rc), -rc, osmo_hexdump(msg->data, msg->len)); return rc; } if (!osmo_imsi_str_valid(gsup.imsi)) { LOG_REMOTE_HLR_MSG(rh, &gsup, LOGL_ERROR, "Invalid IMSI\n"); remote_hlr_err_reply(rh, &gsup, GMM_CAUSE_INV_MAND_INFO); return -GMM_CAUSE_INV_MAND_INFO; } if (proxy_subscr_get_by_imsi(&proxy_subscr, g_hlr->gs->proxy, gsup.imsi)) { LOG_REMOTE_HLR_MSG(rh, &gsup, LOGL_ERROR, "No proxy entry for this IMSI\n"); remote_hlr_err_reply(rh, &gsup, GMM_CAUSE_NET_FAIL); return -GMM_CAUSE_NET_FAIL; } rc = proxy_subscr_forward_to_vlr(g_hlr->gs->proxy, &proxy_subscr, &gsup, rh); if (rc) { LOG_REMOTE_HLR_MSG(rh, &gsup, LOGL_ERROR, "Failed to forward GSUP message towards VLR\n"); remote_hlr_err_reply(rh, &gsup, GMM_CAUSE_NET_FAIL); return -GMM_CAUSE_NET_FAIL; } return 0; } struct remote_hlr_pending_up { struct llist_head entry; remote_hlr_connect_result_cb_t connect_result_cb; void *data; }; static bool remote_hlr_up_down(struct osmo_gsup_client *gsupc, bool up) { struct remote_hlr *remote_hlr = gsupc->data; struct remote_hlr_pending_up *p, *n; if (!up) { LOG_REMOTE_HLR(remote_hlr, LOGL_NOTICE, "link to remote HLR is down, removing GSUP client\n"); remote_hlr_destroy(remote_hlr); return false; } LOG_REMOTE_HLR(remote_hlr, LOGL_NOTICE, "link up\n"); llist_for_each_entry_safe(p, n, &remote_hlr->pending_up_callbacks, entry) { if (p->connect_result_cb) p->connect_result_cb(&remote_hlr->addr, remote_hlr, p->data); llist_del(&p->entry); } return true; } bool remote_hlr_is_up(struct remote_hlr *remote_hlr) { return remote_hlr && remote_hlr->gsupc && remote_hlr->gsupc->is_connected; } struct remote_hlr *remote_hlr_get_or_connect(const struct osmo_sockaddr_str *addr, bool connect, remote_hlr_connect_result_cb_t connect_result_cb, void *data) { struct remote_hlr *rh = NULL; struct remote_hlr *rh_i; struct osmo_gsup_client_config cfg; llist_for_each_entry(rh_i, &remote_hlrs, entry) { if (!osmo_sockaddr_str_cmp(&rh_i->addr, addr)) { rh = rh_i; break; } } if (rh) goto add_result_cb; if (!connect) { if (connect_result_cb) connect_result_cb(addr, NULL, data); return NULL; } /* Doesn't exist yet, create a GSUP client to remote HLR. */ cfg = (struct osmo_gsup_client_config){ .ipa_dev = &g_hlr->gsup_unit_name, .ip_addr = addr->ip, .tcp_port = addr->port, .oapc_config = NULL, .read_cb = remote_hlr_rx, .up_down_cb = remote_hlr_up_down, .data = rh, }; rh = talloc_zero(dgsm_ctx, struct remote_hlr); OSMO_ASSERT(rh); *rh = (struct remote_hlr){ .addr = *addr, .gsupc = osmo_gsup_client_create3(rh, &cfg), }; INIT_LLIST_HEAD(&rh->pending_up_callbacks); if (!rh->gsupc) { LOGP(DDGSM, LOGL_ERROR, "Failed to establish connection to remote HLR " OSMO_SOCKADDR_STR_FMT "\n", OSMO_SOCKADDR_STR_FMT_ARGS(addr)); talloc_free(rh); if (connect_result_cb) connect_result_cb(addr, NULL, data); return NULL; } rh->gsupc->data = rh; llist_add(&rh->entry, &remote_hlrs); add_result_cb: if (connect_result_cb) { if (remote_hlr_is_up(rh)) { connect_result_cb(addr, rh, data); } else { struct remote_hlr_pending_up *p; p = talloc_zero(rh, struct remote_hlr_pending_up); OSMO_ASSERT(p); p->connect_result_cb = connect_result_cb; p->data = data; llist_add_tail(&p->entry, &rh->pending_up_callbacks); } } return rh; } void remote_hlr_destroy(struct remote_hlr *remote_hlr) { osmo_gsup_client_destroy(remote_hlr->gsupc); remote_hlr->gsupc = NULL; llist_del(&remote_hlr->entry); talloc_free(remote_hlr); } /* This function takes ownership of the msg, do not free it after passing to this function. */ int remote_hlr_msgb_send(struct remote_hlr *remote_hlr, struct msgb *msg) { int rc = osmo_gsup_client_send(remote_hlr->gsupc, msg); if (rc) { LOGP(DDGSM, LOGL_ERROR, "Failed to send GSUP message to " OSMO_SOCKADDR_STR_FMT "\n", OSMO_SOCKADDR_STR_FMT_ARGS(&remote_hlr->addr)); } return rc; } /* A GSUP message was received from the MS/MSC side, forward it to the remote HLR. */ void remote_hlr_gsup_forward_to_remote_hlr(struct remote_hlr *remote_hlr, struct osmo_gsup_req *req, struct osmo_gsup_message *modified_gsup) { int rc; struct msgb *msg; /* To forward to a remote HLR, we need to indicate the source MSC's name in the Source Name IE to make sure the * reply can be routed back. Store the sender MSC in gsup->source_name -- the remote HLR is required to return * this as gsup->destination_name so that the reply gets routed to the original MSC. */ struct osmo_gsup_message forward; if (modified_gsup) forward = *modified_gsup; else forward = req->gsup; if (req->source_name.type != OSMO_CNI_PEER_ID_IPA_NAME) { osmo_gsup_req_respond_err(req, GMM_CAUSE_NET_FAIL, "Unsupported GSUP peer id type: %s", osmo_cni_peer_id_type_name(req->source_name.type)); return; } forward.source_name = req->source_name.ipa_name.val; forward.source_name_len = req->source_name.ipa_name.len; msg = osmo_gsup_msgb_alloc("GSUP proxy to remote HLR"); rc = osmo_gsup_encode(msg, &forward); if (rc) { osmo_gsup_req_respond_err(req, GMM_CAUSE_NET_FAIL, "Failed to encode GSUP message for forwarding"); return; } remote_hlr_msgb_send(remote_hlr, msg); osmo_gsup_req_free(req); }