Change in osmo-bsc-nat[master]: bsc_nat_fsm: initial conn-oriented forwarding

osmith has submitted this change. ( https://gerrit.osmocom.org/c/osmo-bsc-nat/+/27260 ) Change subject: bsc_nat_fsm: initial conn-oriented forwarding ...................................................................... bsc_nat_fsm: initial conn-oriented forwarding Implement a simple version of forwarding Connection Request, Connection Confirm, Data Form, Released SCCP messages. This is still assuming that there is just one BSC, one MSC, the same connection ID is used in RAN and CN. Future patches will add a mapping between RAN and CN sides and allow multiple BSCs. With this patch it is possible to perform a call between two MS in the following network structure: MS1 --. BTS --- BSC --- BSCNAT --- MSC MS2 --' Related: SYS#5560 Change-Id: I3df79e4dfaa60f4fd098961ee57cda71e9773b82 --- M src/osmo-bsc-nat/bsc_nat_fsm.c 1 file changed, 87 insertions(+), 2 deletions(-) Approvals: Jenkins Builder: Verified laforge: Looks good to me, but someone else must approve pespin: Looks good to me, but someone else must approve osmith: Looks good to me, approved diff --git a/src/osmo-bsc-nat/bsc_nat_fsm.c b/src/osmo-bsc-nat/bsc_nat_fsm.c index 3161de3..906fd94 100644 --- a/src/osmo-bsc-nat/bsc_nat_fsm.c +++ b/src/osmo-bsc-nat/bsc_nat_fsm.c @@ -69,6 +69,31 @@ return g_bsc_nat->cn; } +/* For connection-oriented messages, figure out which side is the BSCNAT, + * either the called_addr or calling_addr. */ +static int sccp_sap_get_peer_addr_in(struct bsc_nat_ss7_inst *src, struct osmo_sccp_addr **peer_addr_in, + struct osmo_sccp_addr *called_addr, struct osmo_sccp_addr *calling_addr) +{ + if (osmo_sccp_addr_ri_cmp(&src->local_sccp_addr, called_addr) == 0) { + *peer_addr_in = called_addr; + return 0; + } else if (osmo_sccp_addr_ri_cmp(&src->local_sccp_addr, calling_addr) == 0) { + *peer_addr_in = calling_addr; + return 0; + } + + char buf_called[255]; + char buf_calling[255]; + + osmo_sccp_addr_to_str_buf(buf_called, sizeof(buf_called), NULL, called_addr); + osmo_sccp_addr_to_str_buf(buf_calling, sizeof(buf_calling), NULL, calling_addr); + + LOG_SCCP(src, NULL, LOGL_ERROR, "Invalid connection oriented message, locally configured address %s" + " is neither called address %s nor calling address %s!\n", + osmo_sccp_inst_addr_name(NULL, &src->local_sccp_addr), buf_called, buf_calling); + return -1; +} + /* Figure out who will receive the message. * For now this is simplified by assuming there is only one MSC, one BSC. */ static int sccp_sap_get_peer_addr_out(struct bsc_nat_ss7_inst *src, struct osmo_sccp_addr *peer_addr_in, @@ -94,6 +119,8 @@ return 0; } +/* Handle incoming messages. For now this is simplified by assuming there is + * only one MSC, one BSC (not yet translating connection ids etc.). */ static int sccp_sap_up(struct osmo_prim_hdr *oph, void *scu) { struct bsc_nat_ss7_inst *src = osmo_sccp_user_get_priv(scu); @@ -104,20 +131,78 @@ int rc = -1; switch (OSMO_PRIM_HDR(oph)) { + case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_CONFIRM): + /* indication of connection confirm */ + LOG_SCCP(src, NULL, LOGL_DEBUG, "%s(%s)\n", __func__, osmo_scu_prim_name(oph)); + + if (sccp_sap_get_peer_addr_in(src, &peer_addr_in, &prim->u.connect.called_addr, + &prim->u.connect.calling_addr) < 0) + goto error; + + if (sccp_sap_get_peer_addr_out(src, peer_addr_in, &peer_addr_out) < 0) + goto error; + + LOG_SCCP(src, peer_addr_in, LOGL_NOTICE, "Forwarding to %s in %s\n", + osmo_sccp_inst_addr_name(NULL, &peer_addr_out), + dest == g_bsc_nat->ran ? "RAN" : "CN"); + + msgb_pull_to_l2(oph->msg); + osmo_sccp_tx_conn_resp(dest->scu, prim->u.connect.conn_id, &peer_addr_out, oph->msg->data, + msgb_length(oph->msg)); + rc = 0; + break; + case OSMO_PRIM(OSMO_SCU_PRIM_N_CONNECT, PRIM_OP_INDICATION): /* indication of new inbound connection request */ - peer_addr_in = &prim->u.connect.calling_addr; - LOG_SCCP(src, peer_addr_in, LOGL_DEBUG, "%s(%s)\n", __func__, osmo_scu_prim_name(oph)); + LOG_SCCP(src, NULL, LOGL_DEBUG, "%s(%s)\n", __func__, osmo_scu_prim_name(oph)); + + if (sccp_sap_get_peer_addr_in(src, &peer_addr_in, &prim->u.connect.called_addr, + &prim->u.connect.calling_addr) < 0) + goto error; + + if (sccp_sap_get_peer_addr_out(src, peer_addr_in, &peer_addr_out) < 0) + goto error; + + LOG_SCCP(src, peer_addr_in, LOGL_NOTICE, "Forwarding to %s in %s\n", + osmo_sccp_inst_addr_name(NULL, &peer_addr_out), + dest == g_bsc_nat->ran ? "RAN" : "CN"); + + msgb_pull_to_l2(oph->msg); + osmo_sccp_tx_conn_req(dest->scu, prim->u.connect.conn_id, &dest->local_sccp_addr, &peer_addr_out, + oph->msg->data, msgb_length(oph->msg)); + rc = 0; break; case OSMO_PRIM(OSMO_SCU_PRIM_N_DATA, PRIM_OP_INDICATION): /* connection-oriented data received */ LOG_SCCP(src, NULL, LOGL_DEBUG, "%s(%s)\n", __func__, osmo_scu_prim_name(oph)); + + if (sccp_sap_get_peer_addr_out(src, NULL, &peer_addr_out) < 0) + goto error; + + LOG_SCCP(src, NULL, LOGL_NOTICE, "Forwarding to %s in %s\n", + osmo_sccp_inst_addr_name(NULL, &peer_addr_out), + dest == g_bsc_nat->ran ? "RAN" : "CN"); + + msgb_pull_to_l2(oph->msg); + osmo_sccp_tx_data(dest->scu, prim->u.data.conn_id, oph->msg->data, msgb_length(oph->msg)); + rc = 0; break; case OSMO_PRIM(OSMO_SCU_PRIM_N_DISCONNECT, PRIM_OP_INDICATION): /* indication of disconnect */ LOG_SCCP(src, NULL, LOGL_DEBUG, "%s(%s)\n", __func__, osmo_scu_prim_name(oph)); + + if (sccp_sap_get_peer_addr_out(src, NULL, &peer_addr_out) < 0) + goto error; + + LOG_SCCP(src, NULL, LOGL_NOTICE, "Forwarding to %s in %s\n", + osmo_sccp_inst_addr_name(NULL, &peer_addr_out), + dest == g_bsc_nat->ran ? "RAN" : "CN"); + + osmo_sccp_tx_disconn(dest->scu, prim->u.disconnect.conn_id, &prim->u.disconnect.responding_addr, + prim->u.disconnect.cause); + rc = 0; break; case OSMO_PRIM(OSMO_SCU_PRIM_N_UNITDATA, PRIM_OP_INDICATION): -- To view, visit https://gerrit.osmocom.org/c/osmo-bsc-nat/+/27260 To unsubscribe, or for help writing mail filters, visit https://gerrit.osmocom.org/settings Gerrit-Project: osmo-bsc-nat Gerrit-Branch: master Gerrit-Change-Id: I3df79e4dfaa60f4fd098961ee57cda71e9773b82 Gerrit-Change-Number: 27260 Gerrit-PatchSet: 5 Gerrit-Owner: osmith &lt;osmith(a)sysmocom.de&gt; Gerrit-Reviewer: Jenkins Builder Gerrit-Reviewer: fixeria &lt;vyanitskiy(a)sysmocom.de&gt; Gerrit-Reviewer: laforge &lt;laforge(a)osmocom.org&gt; Gerrit-Reviewer: osmith &lt;osmith(a)sysmocom.de&gt; Gerrit-Reviewer: pespin &lt;pespin(a)sysmocom.de&gt; Gerrit-MessageType: merged