WIP

lib/gtp/v1/types.c

@@ -398,3 +398,197 @@ int16_t ogs_gtp1_build_qos_profile(ogs_tlv_octet_t *octet,
         octet->len = 6;
     return octet->len;
 }
+
+/* The format of EUA in PDP Context is not exactly the same for the entire EUA,
+ * hence a separate function is required to encode the value part of the address,
+ * instead of using regular ogs_gtp1_ip_to_eua(). */
+static int enc_pdp_ctx_as_eua(uint8_t pdu_session_type, const ogs_ip_t *ip,
+                              uint8_t *data, int data_len)
+{
+    switch (pdu_session_type)
+    {
+    case OGS_PDU_SESSION_TYPE_IPV4:
+        if (!ip->ipv4) {
+            ogs_error("EUA type IPv4 but no IPv4 address available");
+            return OGS_ERROR;
+        }
+        if (data_len < OGS_IPV4_LEN)
+            return OGS_ERROR;
+        memcpy(data, &ip->addr, OGS_IPV4_LEN);
+        return OGS_IPV4_LEN;
+    case OGS_PDU_SESSION_TYPE_IPV6:
+        if (!ip->ipv6) {
+            ogs_error("EUA type IPv4 but no IPv6 address available");
+            return OGS_ERROR;
+        }
+        if (data_len < OGS_IPV6_LEN)
+            return OGS_ERROR;
+        memcpy(data, ip->addr6, OGS_IPV6_LEN);
+        return OGS_IPV6_LEN;
+    case OGS_PDU_SESSION_TYPE_IPV4V6:
+        if (ip->ipv4 && ip->ipv6) {
+            if (data_len < OGS_IPV4_LEN + OGS_IPV6_LEN)
+                return OGS_ERROR;
+            memcpy(data, &ip->addr, OGS_IPV4_LEN);
+            memcpy(data + OGS_IPV4_LEN, ip->addr6, OGS_IPV6_LEN);
+            return OGS_IPV4_LEN + OGS_IPV6_LEN;
+        } else if (ip->ipv4) {
+            if (data_len < OGS_IPV4_LEN)
+                return OGS_ERROR;
+            memcpy(data, &ip->addr, OGS_IPV4_LEN);
+            return OGS_IPV4_LEN;
+        } else if (ip->ipv6) {
+            if (data_len < OGS_IPV6_LEN)
+                return OGS_ERROR;
+            memcpy(data, ip->addr6, OGS_IPV6_LEN);
+            return OGS_IPV6_LEN;
+        } else {
+            ogs_error("EUA type IPv4 but no IPv4 nor IPv6 address available");
+            return OGS_ERROR;
+        }
+        break;
+    default:
+        ogs_error("Unexpected session type");
+        return OGS_ERROR;
+    }
+    return OGS_OK;
+}
+
+int ogs_gtp1_build_pdp_context(ogs_tlv_octet_t *octet,
+    const ogs_gtp1_pdp_context_decoded_t *decoded, uint8_t *data, int data_len)
+{
+    uint8_t *ptr = data;
+    uint16_t val16;
+    uint32_t val32;
+    int rv;
+
+    ogs_assert(octet);
+    ogs_assert(data);
+    ogs_assert((size_t)data_len >= 1);
+
+    octet->data = data;
+
+#define CHECK_SPACE_ERR(bytes) \
+    if ((ptr - data) + (bytes) > data_len) \
+        return OGS_ERROR
+
+    CHECK_SPACE_ERR(1);
+    *ptr++ = (decoded->ea << 7) | (decoded->vaa << 6) |
+             (decoded->asi << 5)| (decoded->order << 4) |
+             (decoded->nsapi & 0x0f);
+
+    CHECK_SPACE_ERR(1);
+    *ptr++ = (decoded->sapi & 0x0f);
+
+    CHECK_SPACE_ERR(1);
+    *ptr++ = decoded->qos_sub_len;
+    CHECK_SPACE_ERR(decoded->qos_sub_len);
+    memcpy(ptr, &decoded->qos_sub[0], decoded->qos_sub_len);
+    ptr += decoded->qos_sub_len;
+
+    CHECK_SPACE_ERR(1);
+    *ptr++ = decoded->qos_req_len;
+    CHECK_SPACE_ERR(decoded->qos_req_len);
+    memcpy(ptr, &decoded->qos_req[0], decoded->qos_req_len);
+    ptr += decoded->qos_req_len;
+
+    CHECK_SPACE_ERR(1);
+    *ptr++ = decoded->qos_neg_len;
+    CHECK_SPACE_ERR(decoded->qos_neg_len);
+    memcpy(ptr, &decoded->qos_neg[0], decoded->qos_neg_len);
+    ptr += decoded->qos_neg_len;
+
+    CHECK_SPACE_ERR(2);
+    val16 = htobe16(decoded->snd);
+    memcpy(ptr, &val16, 2);
+    ptr += 2;
+
+    CHECK_SPACE_ERR(2);
+    val16 = htobe16(decoded->snu);
+    memcpy(ptr, &val16, 2);
+    ptr += 2;
+
+    CHECK_SPACE_ERR(1);
+    *ptr++ = decoded->send_npdu_nr;
+
+    CHECK_SPACE_ERR(1);
+    *ptr++ = decoded->receive_npdu_nr;
+
+    CHECK_SPACE_ERR(4);
+    val32 = htobe32(decoded->ul_teic);
+    memcpy(ptr, &val32, 4);
+    ptr += 4;
+
+    CHECK_SPACE_ERR(4);
+    val32 = htobe32(decoded->ul_teid);
+    memcpy(ptr, &val32, 4);
+    ptr += 4;
+
+    CHECK_SPACE_ERR(1);
+    *ptr++ = decoded->pdp_ctx_id;
+
+    CHECK_SPACE_ERR(1);
+    *ptr++ = 0xf0 | decoded->pdp_type_org;
+    CHECK_SPACE_ERR(1);
+    *ptr++ = decoded->pdp_type_num[0];
+    /* PDP Address Length filled after PDP Address */
+    CHECK_SPACE_ERR(1);
+    rv = enc_pdp_ctx_as_eua(decoded->pdp_type_num[0], &decoded->pdp_address[0],
+                            ptr + 1, (data + data_len) - (ptr + 1));
+    if (rv < 0)
+        return rv;
+    *ptr = rv;
+    ptr += 1 + rv;
+
+    /* GGSN Address for control plane Length */
+    CHECK_SPACE_ERR(1);
+    *ptr = decoded->ggsn_address_c.ogs_sa_family == AF_INET6 ?
+           OGS_GTP_GSN_ADDRESS_IPV6_LEN : OGS_GTP_GSN_ADDRESS_IPV4_LEN;
+    CHECK_SPACE_ERR(1 + (*ptr));
+    memcpy(ptr + 1,
+           decoded->ggsn_address_c.ogs_sa_family == AF_INET6 ?
+                (uint8_t *)decoded->ggsn_address_c.sin6.sin6_addr.s6_addr :
+                (uint8_t *)&decoded->ggsn_address_c.sin.sin_addr.s_addr,
+                *ptr);
+    ptr += 1 + *ptr;
+
+    /* GGSN Address for User Traffic Length */
+    CHECK_SPACE_ERR(1);
+    *ptr = decoded->ggsn_address_u.ogs_sa_family == AF_INET6 ?
+           OGS_GTP_GSN_ADDRESS_IPV6_LEN : OGS_GTP_GSN_ADDRESS_IPV4_LEN;
+    CHECK_SPACE_ERR(1 + (*ptr));
+    memcpy(ptr + 1,
+           decoded->ggsn_address_u.ogs_sa_family == AF_INET6 ?
+                (uint8_t *)decoded->ggsn_address_u.sin6.sin6_addr.s6_addr :
+                (uint8_t *)&decoded->ggsn_address_u.sin.sin_addr.s_addr,
+                *ptr);
+    ptr += 1 + *ptr;
+
+    /* APN */
+    rv = strlen(decoded->apn);
+    CHECK_SPACE_ERR(1 + rv + 1);
+    *ptr = ogs_fqdn_build(
+            (char *)ptr + 1, decoded->apn, rv);
+    ptr += 1 + *ptr;
+
+    CHECK_SPACE_ERR(2);
+    *ptr++ = (decoded->trans_id >> 8) & 0x0f;
+    *ptr++ = decoded->trans_id & 0xff;
+
+    if (decoded->ea) {
+        CHECK_SPACE_ERR(1);
+        *ptr++ = decoded->pdp_type_num[1];
+        /* PDP Address Length filled after PDP Address */
+        CHECK_SPACE_ERR(1);
+        rv = enc_pdp_ctx_as_eua(decoded->pdp_type_num[1], &decoded->pdp_address[1],
+                                ptr + 1, (data + data_len) - (ptr + 1));
+        if (rv < 0)
+            return rv;
+        *ptr = rv;
+        ptr += 1 + rv;
+    }
+
+    octet->len = (ptr - data);
+    return octet->len;
+#undef CHECK_SPACE_ERR
+}

lib/gtp/v1/types.h

@@ -300,4 +300,52 @@ int16_t ogs_gtp1_parse_qos_profile(
 int16_t ogs_gtp1_build_qos_profile(ogs_tlv_octet_t *octet,
     const ogs_gtp1_qos_profile_decoded_t *decoded, void *data, int data_len);
 
+/* 7.7.29 Table 48 Reordering Required Values */
+#define OGS_GTP1_PDPCTX_REORDERING_REQUIRED_NO 0
+#define OGS_GTP1_PDPCTX_REORDERING_REQUIRED_YES 1
+
+/* 7.7.29 Table 49 VPLMN Address Allowed Values */
+#define OGS_GTP1_PDPCTX_VLPMN_ADDR_ALLOWED_NO 0
+#define OGS_GTP1_PDPCTX_VLPMN_ADDR_ALLOWED_YES 1
+
+/* 7.7.29 Table 49A Activity Status Indicator Value */
+#define OGS_GTP1_PDPCTX_ACTIVITY_STATUS_IND_YES 0
+#define OGS_GTP1_PDPCTX_ACTIVITY_STATUS_IND_NO 1
+
+/* Not explicitly defined in a table: */
+#define OGS_GTP1_PDPCTX_REORDERING_REQUIRED_NO 0
+#define OGS_GTP1_PDPCTX_REORDERING_REQUIRED_YES 1
+
+typedef struct ogs_gtp1_pdp_context_decoded_s {
+    uint8_t ea:1; /* OGS_GTP1_PDPCTX_REORDERING_REQUIRED_* */
+    uint8_t vaa:1; /* OGS_GTP1_PDPCTX_VLPMN_ADDR_ALLOWED_* */
+    uint8_t asi:1; /* OGS_GTP1_PDPCTX_ACTIVITY_STATUS_IND_* */
+    uint8_t order:1; /* OGS_GTP1_PDPCTX_REORDERING_REQUIRED_* */
+    uint8_t nsapi:4;
+    uint8_t sapi:4;
+    uint8_t qos_sub[OGS_GTP1_QOS_PROFILE_MAX_LEN];
+    uint8_t qos_sub_len;
+    uint8_t qos_req[OGS_GTP1_QOS_PROFILE_MAX_LEN];
+    uint8_t qos_req_len;
+    uint8_t qos_neg[OGS_GTP1_QOS_PROFILE_MAX_LEN];
+    uint8_t qos_neg_len;
+    uint16_t snd;
+    uint16_t snu;
+    uint8_t send_npdu_nr;
+    uint8_t receive_npdu_nr;
+    uint32_t ul_teic;
+    uint32_t ul_teid;
+    uint8_t pdp_ctx_id;
+    uint8_t pdp_type_org;
+    uint8_t pdp_type_num[2];
+    ogs_ip_t pdp_address[2];
+    ogs_sockaddr_t ggsn_address_c;
+    ogs_sockaddr_t ggsn_address_u;
+    char apn[OGS_MAX_APN_LEN+1];
+    uint16_t trans_id:12;
+} ogs_gtp1_pdp_context_decoded_t;
+
+int ogs_gtp1_build_pdp_context(ogs_tlv_octet_t *octet,
+    const ogs_gtp1_pdp_context_decoded_t *decoded, uint8_t *data, int data_len);
+
 #endif /* OGS_GTP1_TYPES_H */

src/mme/mme-context.h

@@ -421,6 +421,11 @@ struct mme_ue_s {
     char            a_msisdn_bcd[OGS_MAX_MSISDN_BCD_LEN+1];
 
     mme_p_tmsi_t    p_tmsi;
+    struct {
+        uint32_t        sgsn_gn_teid;
+        ogs_ip_t        sgsn_gn_ip;
+        ogs_ip_t        sgsn_gn_ip_alt;
+    } gn;
 
     struct {
         mme_m_tmsi_t *m_tmsi;

src/mme/mme-gn-build.c

@@ -21,6 +21,75 @@
 
 #include "mme-gn-build.h"
 
+/* 3GPP TS 29.060 7.5.4 SGSN Context Response */
+ogs_pkbuf_t *mme_gn_build_sgsn_context_response(
+                mme_ue_t *mme_ue, uint8_t cause)
+{
+    ogs_gtp1_message_t gtp1_message;
+    ogs_gtp1_sgsn_context_response_t *rsp = NULL;
+    mme_sess_t *sess = NULL;
+    ogs_gtp1_gsn_addr_t mme_gnc_gsnaddr;
+    int gsn_len;
+    int rv;
+
+    ogs_debug("[Gn] build SGSN Context Response");
+
+
+    rsp = &gtp1_message.sgsn_context_response;
+    memset(&gtp1_message, 0, sizeof(ogs_gtp1_message_t));
+    gtp1_message.h.type = OGS_GTP1_SGSN_CONTEXT_RESPONSE_TYPE;
+
+    /* 3GPP TS 29.060 7.7.1 Cause, Mandatory */
+    rsp->cause.presence = 1;
+    rsp->cause.u8 = cause;
+
+    /* 3GPP TS 29.060 7.7.2 IMSI, Conditional */
+    rsp->imsi.presence = !!mme_ue;
+    if (rsp->imsi.presence) {
+        rsp->imsi.data = mme_ue->imsi;
+        rsp->imsi.len = mme_ue->imsi_len;
+    }
+
+    if (cause != OGS_GTP1_CAUSE_REQUEST_ACCEPTED)
+        goto build_ret;
+
+    ogs_assert(mme_ue);
+
+    /* FIXME: Reuse S11 TEID as local Gn interface for now */
+    rsp->tunnel_endpoint_identifier_control_plane.presence = 1;
+    rsp->tunnel_endpoint_identifier_control_plane.u32 = mme_ue->mme_s11_teid;
+
+    ogs_list_for_each(&mme_ue->sess_list, sess) {
+        if (!MME_HAVE_SGW_S1U_PATH(sess))
+            continue;
+        /* TODO: fill some structure with pdp contexts */
+    }
+
+    /* SGSN Address for Control Plane */
+    if (ogs_gtp_self()->gtpc_addr6 &&
+        (mme_ue->gn.sgsn_gn_ip.ipv6 || mme_ue->gn.sgsn_gn_ip_alt.ipv6)) {
+        rv = ogs_gtp1_sockaddr_to_gsn_addr(NULL, ogs_gtp_self()->gtpc_addr6,
+                &mme_gnc_gsnaddr, &gsn_len);
+        if (rv != OGS_OK) {
+            ogs_error("ogs_gtp1_sockaddr_to_gsn_addr() failed");
+            return NULL;
+        }
+    } else {
+        rv = ogs_gtp1_sockaddr_to_gsn_addr(NULL, ogs_gtp_self()->gtpc_addr,
+                &mme_gnc_gsnaddr, &gsn_len);
+        if (rv != OGS_OK) {
+            ogs_error("ogs_gtp1_sockaddr_to_gsn_addr() failed");
+            return NULL;
+        }
+    }
+    rsp->sgsn_address_for_control_plane.presence = 1;
+    rsp->sgsn_address_for_control_plane.data = &mme_gnc_gsnaddr;
+    rsp->sgsn_address_for_control_plane.len = gsn_len;
+
+build_ret:
+    return ogs_gtp1_build_msg(&gtp1_message);
+}
+
 /* 3GPP TS 29.060 7.5.14.1 RAN Information Relay */
 ogs_pkbuf_t *mme_gn_build_ran_information_relay(
                 uint8_t type, const uint8_t *buf, size_t len,
@@ -59,4 +128,4 @@ ogs_pkbuf_t *mme_gn_build_ran_information_relay(
 
     gtp1_message.h.type = type;
     return ogs_gtp1_build_msg(&gtp1_message);
-}
+}

src/mme/mme-gn-build.h

@@ -30,6 +30,9 @@ extern "C" {
 }
 #endif
 
+ogs_pkbuf_t *mme_gn_build_sgsn_context_response(
+                mme_ue_t *mme_ue, uint8_t cause);
+
 ogs_pkbuf_t *mme_gn_build_ran_information_relay(
                 uint8_t type, const uint8_t *buf, size_t len,
                 const ogs_nas_rai_t *rai, uint16_t cell_id);