| /*! \file gprs_ns2_udp.c |
| * NS-over-UDP implementation. |
| * GPRS Networks Service (NS) messages on the Gb interface. |
| * 3GPP TS 08.16 version 8.0.1 Release 1999 / ETSI TS 101 299 V8.0.1 (2002-05) |
| * as well as its successor 3GPP TS 48.016 */ |
| |
| /* (C) 2020 sysmocom - s.f.m.c. GmbH |
| * Author: Alexander Couzens <lynxis@fe80.eu> |
| * |
| * All Rights Reserved |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 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 General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| * |
| */ |
| |
| #include <errno.h> |
| |
| #include <osmocom/core/osmo_io.h> |
| #include <osmocom/core/select.h> |
| #include <osmocom/core/sockaddr_str.h> |
| #include <osmocom/core/socket.h> |
| #include <osmocom/gprs/gprs_ns2.h> |
| |
| #include "common_vty.h" |
| #include "gprs_ns2_internal.h" |
| |
| |
| static void free_bind(struct gprs_ns2_vc_bind *bind); |
| |
| |
| struct gprs_ns2_vc_driver vc_driver_ip = { |
| .name = "GB UDP IPv4/IPv6", |
| .free_bind = free_bind, |
| }; |
| |
| struct priv_bind { |
| struct osmo_io_fd *iofd; |
| struct osmo_sockaddr addr; |
| int dscp; |
| uint8_t priority; |
| }; |
| |
| struct priv_vc { |
| struct osmo_sockaddr remote; |
| }; |
| |
| /*! clean up all private driver state. Should be only called by gprs_ns2_free_bind() */ |
| static void free_bind(struct gprs_ns2_vc_bind *bind) |
| { |
| struct priv_bind *priv; |
| |
| if (!bind) |
| return; |
| |
| OSMO_ASSERT(gprs_ns2_is_ip_bind(bind)); |
| |
| priv = bind->priv; |
| |
| osmo_iofd_free(priv->iofd); |
| priv->iofd = NULL; |
| talloc_free(priv); |
| } |
| |
| static void free_vc(struct gprs_ns2_vc *nsvc) |
| { |
| if (!nsvc) |
| return; |
| |
| if (!nsvc->priv) |
| return; |
| |
| OSMO_ASSERT(gprs_ns2_is_ip_bind(nsvc->bind)); |
| talloc_free(nsvc->priv); |
| nsvc->priv = NULL; |
| } |
| |
| static void dump_vty(const struct gprs_ns2_vc_bind *bind, |
| struct vty *vty, bool stats) |
| { |
| struct priv_bind *priv; |
| struct gprs_ns2_vc *nsvc; |
| struct osmo_sockaddr_str sockstr = {}; |
| unsigned long nsvcs = 0; |
| |
| if (!bind) |
| return; |
| |
| priv = bind->priv; |
| if (osmo_sockaddr_str_from_sockaddr(&sockstr, &priv->addr.u.sas)) |
| strcpy(sockstr.ip, "invalid"); |
| |
| llist_for_each_entry(nsvc, &bind->nsvc, blist) { |
| nsvcs++; |
| } |
| |
| vty_out(vty, "UDP bind: %s:%d DSCP: %d Priority: %u%s", sockstr.ip, sockstr.port, |
| priv->dscp, priv->priority, VTY_NEWLINE); |
| vty_out(vty, " IP-SNS signalling weight: %u data weight: %u%s", |
| bind->sns_sig_weight, bind->sns_data_weight, VTY_NEWLINE); |
| vty_out(vty, " %lu NS-VC:%s", nsvcs, VTY_NEWLINE); |
| |
| llist_for_each_entry(nsvc, &bind->nsvc, blist) { |
| ns2_vty_dump_nsvc(vty, nsvc, stats); |
| } |
| } |
| |
| |
| /*! Find a NS-VC by its remote socket address. |
| * \param[in] bind in which to search |
| * \param[in] rem_addr remote peer socket address to search |
| * \returns NS-VC matching sockaddr; NULL if none found */ |
| struct gprs_ns2_vc *gprs_ns2_nsvc_by_sockaddr_bind(struct gprs_ns2_vc_bind *bind, |
| const struct osmo_sockaddr *rem_addr) |
| { |
| struct gprs_ns2_vc *nsvc; |
| struct priv_vc *vcpriv; |
| |
| OSMO_ASSERT(gprs_ns2_is_ip_bind(bind)); |
| |
| llist_for_each_entry(nsvc, &bind->nsvc, blist) { |
| vcpriv = nsvc->priv; |
| if (vcpriv->remote.u.sa.sa_family != rem_addr->u.sa.sa_family) |
| continue; |
| if (osmo_sockaddr_cmp(&vcpriv->remote, rem_addr)) |
| continue; |
| |
| return nsvc; |
| } |
| |
| return NULL; |
| } |
| |
| static inline int nsip_sendmsg(struct gprs_ns2_vc_bind *bind, |
| struct msgb *msg, |
| const struct osmo_sockaddr *dest) |
| { |
| struct priv_bind *priv = bind->priv; |
| |
| return osmo_iofd_sendto_msgb(priv->iofd, msg, 0, dest); |
| } |
| |
| /*! send the msg and free it afterwards. |
| * \param nsvc NS-VC on which the message shall be sent |
| * \param msg message to be sent |
| * \return number of bytes transmitted; negative on error */ |
| static int nsip_vc_sendmsg(struct gprs_ns2_vc *nsvc, struct msgb *msg) |
| { |
| int rc; |
| struct gprs_ns2_vc_bind *bind = nsvc->bind; |
| struct priv_vc *priv = nsvc->priv; |
| |
| rc = nsip_sendmsg(bind, msg, &priv->remote); |
| |
| return rc; |
| } |
| |
| static struct priv_vc *ns2_driver_alloc_vc(struct gprs_ns2_vc_bind *bind, struct gprs_ns2_vc *nsvc, const struct osmo_sockaddr *remote) |
| { |
| struct priv_vc *priv = talloc_zero(bind, struct priv_vc); |
| if (!priv) |
| return NULL; |
| |
| nsvc->priv = priv; |
| priv->remote = *remote; |
| |
| return priv; |
| } |
| |
| static void handle_nsip_recvfrom(struct osmo_io_fd *iofd, int error, struct msgb *msg, |
| const struct osmo_sockaddr *saddr) |
| { |
| int rc = 0; |
| struct gprs_ns2_vc_bind *bind = osmo_iofd_get_data(iofd); |
| struct gprs_ns2_vc *nsvc; |
| |
| struct msgb *reject; |
| |
| msg->l2h = msgb_data(msg); |
| |
| /* check if a vc is available */ |
| nsvc = gprs_ns2_nsvc_by_sockaddr_bind(bind, saddr); |
| if (!nsvc) { |
| /* VC not found */ |
| rc = ns2_create_vc(bind, msg, saddr, "newconnection", &reject, &nsvc); |
| switch (rc) { |
| case NS2_CS_FOUND: |
| break; |
| case NS2_CS_ERROR: |
| case NS2_CS_SKIPPED: |
| rc = 0; |
| goto out; |
| case NS2_CS_REJECTED: |
| /* nsip_sendmsg will free reject */ |
| rc = nsip_sendmsg(bind, reject, saddr); |
| goto out; |
| case NS2_CS_CREATED: |
| ns2_driver_alloc_vc(bind, nsvc, saddr); |
| /* only start the fsm for non SNS. SNS will take care of its own */ |
| if (nsvc->nse->dialect != GPRS_NS2_DIALECT_SNS) |
| ns2_vc_fsm_start(nsvc); |
| break; |
| } |
| } |
| |
| ns2_recv_vc(nsvc, msg); |
| return; |
| |
| out: |
| msgb_free(msg); |
| } |
| |
| static void handle_nsip_sendto(struct osmo_io_fd *iofd, int res, |
| const struct msgb *msg, |
| const struct osmo_sockaddr *daddr) |
| { |
| struct gprs_ns2_vc_bind *bind = osmo_iofd_get_data(iofd); |
| struct gprs_ns2_vc *nsvc; |
| |
| nsvc = gprs_ns2_nsvc_by_sockaddr_bind(bind, daddr); |
| if (!nsvc) |
| return; |
| |
| if (OSMO_LIKELY(res >= 0)) { |
| RATE_CTR_INC_NS(nsvc, NS_CTR_PKTS_OUT); |
| RATE_CTR_ADD_NS(nsvc, NS_CTR_BYTES_OUT, res); |
| } else { |
| RATE_CTR_INC_NS(nsvc, NS_CTR_PKTS_OUT_DROP); |
| RATE_CTR_ADD_NS(nsvc, NS_CTR_BYTES_OUT_DROP, msgb_length(msg)); |
| } |
| } |
| |
| /*! Find NS bind for a given socket address |
| * \param[in] nsi NS instance |
| * \param[in] sockaddr socket address to search for |
| * \return |
| */ |
| struct gprs_ns2_vc_bind *gprs_ns2_ip_bind_by_sockaddr(struct gprs_ns2_inst *nsi, |
| const struct osmo_sockaddr *sockaddr) |
| { |
| struct gprs_ns2_vc_bind *bind; |
| const struct osmo_sockaddr *local; |
| |
| OSMO_ASSERT(nsi); |
| OSMO_ASSERT(sockaddr); |
| |
| llist_for_each_entry(bind, &nsi->binding, list) { |
| if (!gprs_ns2_is_ip_bind(bind)) |
| continue; |
| |
| local = gprs_ns2_ip_bind_sockaddr(bind); |
| if (!osmo_sockaddr_cmp(sockaddr, local)) |
| return bind; |
| } |
| |
| return NULL; |
| } |
| |
| /*! Bind to an IPv4/IPv6 address |
| * \param[in] nsi NS Instance in which to create the NSVC |
| * \param[in] local the local address to bind to |
| * \param[in] dscp the DSCP/TOS bits used for transmitted data |
| * \param[out] result pointer to the created bind or if a bind with the name exists return the bind. |
| * \return 0 on success; negative on error. -EALREADY returned in case a bind with the name exists */ |
| int gprs_ns2_ip_bind(struct gprs_ns2_inst *nsi, |
| const char *name, |
| const struct osmo_sockaddr *local, |
| int dscp, |
| struct gprs_ns2_vc_bind **result) |
| { |
| struct gprs_ns2_vc_bind *bind; |
| struct priv_bind *priv; |
| int rc; |
| |
| struct osmo_io_ops ioops = { |
| .sendto_cb = &handle_nsip_sendto, |
| .recvfrom_cb = &handle_nsip_recvfrom, |
| }; |
| |
| if (local->u.sa.sa_family != AF_INET && local->u.sa.sa_family != AF_INET6) |
| return -EINVAL; |
| |
| if (dscp < 0 || dscp > 63) |
| return -EINVAL; |
| |
| bind = gprs_ns2_ip_bind_by_sockaddr(nsi, local); |
| if (bind) { |
| if (result) |
| *result = bind; |
| return -EBUSY; |
| } |
| |
| rc = ns2_bind_alloc(nsi, name, &bind); |
| if (rc < 0) |
| return rc; |
| |
| bind->driver = &vc_driver_ip; |
| bind->ll = GPRS_NS2_LL_UDP; |
| /* expect 100 mbit at least. |
| * TODO: ask the network layer about the speed. But would require |
| * notification on change. */ |
| bind->transfer_capability = 100; |
| bind->send_vc = nsip_vc_sendmsg; |
| bind->free_vc = free_vc; |
| bind->dump_vty = dump_vty; |
| |
| priv = bind->priv = talloc_zero(bind, struct priv_bind); |
| if (!priv) { |
| gprs_ns2_free_bind(bind); |
| return -ENOMEM; |
| } |
| |
| priv->addr = *local; |
| priv->dscp = dscp; |
| |
| rc = osmo_sock_init_osa(SOCK_DGRAM, IPPROTO_UDP, |
| local, NULL, |
| OSMO_SOCK_F_BIND | OSMO_SOCK_F_DSCP(priv->dscp)); |
| if (rc < 0) { |
| gprs_ns2_free_bind(bind); |
| return rc; |
| } |
| |
| priv->iofd = osmo_iofd_setup(bind, rc, "NS bind", OSMO_IO_FD_MODE_RECVFROM_SENDTO, &ioops, bind); |
| osmo_iofd_register(priv->iofd, rc); |
| osmo_iofd_set_alloc_info(priv->iofd, 4096, 128); |
| |
| osmo_iofd_read_enable(priv->iofd); |
| osmo_iofd_write_enable(priv->iofd); |
| |
| /* IPv4: max fragmented payload can be (13 bit) * 8 byte => 65535. |
| * IPv6: max payload can be 65535 (RFC 2460). |
| * UDP header = 8 byte */ |
| bind->mtu = 65535 - 8; |
| if (result) |
| *result = bind; |
| |
| return 0; |
| } |
| |
| /*! Create new NS-VC to a given remote address |
| * \param[in] bind the bind we want to connect |
| * \param[in] nse NS entity to be used for the new NS-VC |
| * \param[in] remote remote address to connect to |
| * \return pointer to newly-allocated and connected NS-VC; NULL on error */ |
| struct gprs_ns2_vc *ns2_ip_bind_connect(struct gprs_ns2_vc_bind *bind, |
| struct gprs_ns2_nse *nse, |
| const struct osmo_sockaddr *remote) |
| { |
| struct gprs_ns2_vc *nsvc; |
| const struct osmo_sockaddr *local; |
| struct priv_vc *priv; |
| enum gprs_ns2_vc_mode vc_mode; |
| char idbuf[256], tmp[INET6_ADDRSTRLEN + 8]; |
| |
| OSMO_ASSERT(gprs_ns2_is_ip_bind(bind)); |
| |
| vc_mode = ns2_dialect_to_vc_mode(nse->dialect); |
| if ((int) vc_mode == -1) { |
| LOGNSE(nse, LOGL_ERROR, "Can not derive vc mode from dialect %d. Maybe libosmocore is too old.\n", |
| nse->dialect); |
| return NULL; |
| } |
| |
| /* duplicate */ |
| if (gprs_ns2_nsvc_by_sockaddr_bind(bind, remote)) |
| return NULL; |
| |
| local = gprs_ns2_ip_bind_sockaddr(bind); |
| osmo_sockaddr_to_str_buf(tmp, sizeof(tmp), local); |
| snprintf(idbuf, sizeof(idbuf), "NSE%05u-NSVC-%s-%s-%s", nse->nsei, gprs_ns2_lltype_str(nse->ll), |
| tmp, osmo_sockaddr_to_str(remote)); |
| osmo_identifier_sanitize_buf(idbuf, NULL, '_'); |
| |
| nsvc = ns2_vc_alloc(bind, nse, true, vc_mode, idbuf); |
| if (!nsvc) |
| return NULL; |
| |
| nsvc->priv = talloc_zero(bind, struct priv_vc); |
| if (!nsvc->priv) { |
| gprs_ns2_free_nsvc(nsvc); |
| return NULL; |
| } |
| |
| priv = nsvc->priv; |
| priv->remote = *remote; |
| |
| return nsvc; |
| } |
| |
| /*! Return the socket address of the local peer of a NS-VC. |
| * \param[in] nsvc NS-VC whose local peer we want to know |
| * \return address of the local peer; NULL in case of error */ |
| const struct osmo_sockaddr *gprs_ns2_ip_vc_local(const struct gprs_ns2_vc *nsvc) |
| { |
| struct priv_bind *priv; |
| |
| if (nsvc->bind->driver != &vc_driver_ip) |
| return NULL; |
| |
| priv = nsvc->bind->priv; |
| return &priv->addr; |
| } |
| |
| /*! Return the socket address of the remote peer of a NS-VC. |
| * \param[in] nsvc NS-VC whose remote peer we want to know |
| * \return address of the remote peer; NULL in case of error */ |
| const struct osmo_sockaddr *gprs_ns2_ip_vc_remote(const struct gprs_ns2_vc *nsvc) |
| { |
| struct priv_vc *priv; |
| |
| if (nsvc->bind->driver != &vc_driver_ip) |
| return NULL; |
| |
| priv = nsvc->priv; |
| return &priv->remote; |
| } |
| |
| /*! Compare the NS-VC with the given parameter |
| * \param[in] nsvc NS-VC to compare with |
| * \param[in] local The local address |
| * \param[in] remote The remote address |
| * \param[in] nsvci NS-VCI will only be used if the NS-VC in BLOCKRESET mode otherwise NS-VCI isn't applicable. |
| * \return true if the NS-VC has the same properties as given |
| */ |
| bool gprs_ns2_ip_vc_equal(const struct gprs_ns2_vc *nsvc, |
| const struct osmo_sockaddr *local, |
| const struct osmo_sockaddr *remote, |
| uint16_t nsvci) |
| { |
| struct priv_vc *vpriv; |
| struct priv_bind *bpriv; |
| |
| if (nsvc->bind->driver != &vc_driver_ip) |
| return false; |
| |
| vpriv = nsvc->priv; |
| bpriv = nsvc->bind->priv; |
| |
| if (osmo_sockaddr_cmp(local, &bpriv->addr)) |
| return false; |
| |
| if (osmo_sockaddr_cmp(remote, &vpriv->remote)) |
| return false; |
| |
| if (nsvc->mode == GPRS_NS2_VC_MODE_BLOCKRESET) |
| if (nsvc->nsvci != nsvci) |
| return false; |
| |
| return true; |
| } |
| |
| /*! Return the locally bound socket address of the bind. |
| * \param[in] bind The bind whose local address we want to know |
| * \return address of the local bind */ |
| const struct osmo_sockaddr *gprs_ns2_ip_bind_sockaddr(struct gprs_ns2_vc_bind *bind) |
| { |
| struct priv_bind *priv; |
| OSMO_ASSERT(gprs_ns2_is_ip_bind(bind)); |
| |
| priv = bind->priv; |
| return &priv->addr; |
| } |
| |
| /*! Is the given bind an IP bind? */ |
| int gprs_ns2_is_ip_bind(struct gprs_ns2_vc_bind *bind) |
| { |
| return (bind->driver == &vc_driver_ip); |
| } |
| |
| /*! Set the DSCP (TOS) bit value of the given bind. */ |
| int gprs_ns2_ip_bind_set_dscp(struct gprs_ns2_vc_bind *bind, int dscp) |
| { |
| struct priv_bind *priv; |
| int rc = 0; |
| |
| if (dscp < 0 || dscp > 63) |
| return -EINVAL; |
| |
| OSMO_ASSERT(gprs_ns2_is_ip_bind(bind)); |
| priv = bind->priv; |
| |
| if (dscp != priv->dscp) { |
| priv->dscp = dscp; |
| |
| rc = osmo_sock_set_dscp(osmo_iofd_get_fd(priv->iofd), dscp); |
| if (rc < 0) { |
| LOGBIND(bind, LOGL_ERROR, "Failed to set the DSCP to %u with ret(%d) errno(%d)\n", |
| dscp, rc, errno); |
| } |
| } |
| |
| return rc; |
| } |
| |
| /*! Set the socket priority of the given bind. */ |
| int gprs_ns2_ip_bind_set_priority(struct gprs_ns2_vc_bind *bind, uint8_t priority) |
| { |
| struct priv_bind *priv; |
| int rc = 0; |
| |
| OSMO_ASSERT(gprs_ns2_is_ip_bind(bind)); |
| priv = bind->priv; |
| |
| if (priority != priv->priority) { |
| priv->priority = priority; |
| |
| rc = osmo_sock_set_priority(osmo_iofd_get_fd(priv->iofd), priority); |
| if (rc < 0) { |
| LOGBIND(bind, LOGL_ERROR, "Failed to set the priority to %u with ret(%d) errno(%d)\n", |
| priority, rc, errno); |
| } |
| } |
| |
| return rc; |
| } |
| |
| |
| /*! Count UDP binds compatible with remote */ |
| int ns2_ip_count_bind(struct gprs_ns2_inst *nsi, struct osmo_sockaddr *remote) |
| { |
| struct gprs_ns2_vc_bind *bind; |
| const struct osmo_sockaddr *sa; |
| int count = 0; |
| |
| llist_for_each_entry(bind, &nsi->binding, list) { |
| if (!gprs_ns2_is_ip_bind(bind)) |
| continue; |
| |
| sa = gprs_ns2_ip_bind_sockaddr(bind); |
| if (!sa) |
| continue; |
| |
| if (sa->u.sa.sa_family == remote->u.sa.sa_family) |
| count++; |
| } |
| |
| return count; |
| } |
| |
| /* return the matching bind by index */ |
| struct gprs_ns2_vc_bind *ns2_ip_get_bind_by_index(struct gprs_ns2_inst *nsi, |
| struct osmo_sockaddr *remote, |
| int index) |
| { |
| struct gprs_ns2_vc_bind *bind; |
| const struct osmo_sockaddr *sa; |
| int i = 0; |
| |
| llist_for_each_entry(bind, &nsi->binding, list) { |
| if (!gprs_ns2_is_ip_bind(bind)) |
| continue; |
| |
| sa = gprs_ns2_ip_bind_sockaddr(bind); |
| if (!sa) |
| continue; |
| |
| if (sa->u.sa.sa_family == remote->u.sa.sa_family) { |
| if (index == i) |
| return bind; |
| i++; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| /*! set the signalling and data weight for this bind |
| * \param[in] bind |
| * \param[in] signalling the signalling weight |
| * \param[in] data the data weight |
| */ |
| void gprs_ns2_ip_bind_set_sns_weight(struct gprs_ns2_vc_bind *bind, uint8_t signalling, uint8_t data) |
| { |
| OSMO_ASSERT(gprs_ns2_is_ip_bind(bind)); |
| bind->sns_sig_weight = signalling; |
| bind->sns_data_weight = data; |
| ns2_sns_update_weights(bind); |
| } |