First steps towards a new GTP hub. The aim is to mux GTP connections, so that multiple SGSN <--> GGSN links can pass through a single point. Background: allow having more than one SGSN, possibly in various remote locations.

The recent addition of OAP to GSUP is related to the same background idea.

Sponsored-by: On-Waves ehf

create mode 100644 openbsc/src/gprs/gtphub_main.c

diff --git a/openbsc/include/openbsc/debug.h b/openbsc/include/openbsc/debug.h index 19d8fc2..189ca47 100644 --- a/openbsc/include/openbsc/debug.h +++ b/openbsc/include/openbsc/debug.h @@ -33,6 +33,7 @@ enum { DCTRL, DSMPP, DFILTER, + DGTPHUB, Debug_LastEntry, };

diff --git a/openbsc/src/gprs/gtphub_main.c b/openbsc/src/gprs/gtphub_main.c new file mode 100644 index 0000000..f225efc --- /dev/null +++ b/openbsc/src/gprs/gtphub_main.c @@ -0,0 +1,297 @@ +/* GTP Hub main program */ + +/* (C) 2015 by sysmocom s.f.m.c. GmbH info@sysmocom.de + * All Rights Reserved + * + * Author: Neels Hofmeyr + * + * 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 http://www.gnu.org/licenses/. + */ + +#include <string.h> +#include <stdio.h> +#include <stdlib.h> +#include <errno.h> + +#include <sys/socket.h> +#include <netinet/in.h> + +#define _GNU_SOURCE +#include <getopt.h> + +#include <osmocom/core/application.h> +#include <osmocom/core/utils.h> +#include <osmocom/core/socket.h> +#include <osmocom/core/select.h> +#include <osmocom/core/logging.h> + +#include <openbsc/debug.h> + +#include <gtp.h> + +#include <unistd.h> + +#define LOGERR(fmt, args...) \ + LOGP(DGTPHUB, LOGL_ERROR, fmt, ##args) + +#define LOG(fmt, args...) \ + LOGP(DGTPHUB, LOGL_NOTICE, fmt, ##args) + +extern void *osmo_gtphub_ctx; + +/* TODO move to osmocom/core/socket.c ? */ +#include <netdb.h> +/* The caller is required to call freeaddrinfo(*result), iff zero is returned. */ +/* use this in osmo_sock_init() to remove dup. */ +static int _osmo_getaddrinfo(struct addrinfo **result, + uint16_t family, uint16_t type, uint8_t proto, + const char *host, uint16_t port) +{ + struct addrinfo hints; + char portbuf[16]; + + sprintf(portbuf, "%u", port); + memset(&hints, '\0', sizeof(struct addrinfo)); + hints.ai_family = family; + if (type == SOCK_RAW) { + /* Workaround for glibc, that returns EAI_SERVICE (-8) if + * SOCK_RAW and IPPROTO_GRE is used. + */ + hints.ai_socktype = SOCK_DGRAM; + hints.ai_protocol = IPPROTO_UDP; + } else { + hints.ai_socktype = type; + hints.ai_protocol = proto; + } + + return getaddrinfo(host, portbuf, &hints, result); +} + +/* TODO move to osmocom/core/socket.c ? + * -- will actually disappear when the GGSNs are resolved by DNS. */ +/*! \brief Initialize a sockaddr \param[out] addr valid sockaddr pointer to + * write result to \param[out] addr_len valid pointer to write addr length to + * \param[in] family Address Family like AF_INET, AF_INET6, AF_UNSPEC + * \param[in] type Socket type like SOCK_DGRAM, SOCK_STREAM \param[in] proto + * Protocol like IPPROTO_TCP, IPPROTO_UDP \param[in] host remote host name or + * IP address in string form \param[in] port remote port number in host byte + * order \returns 0 on success, otherwise an error code (from getaddrinfo()). + * + * Copy the first result from a getaddrinfo() call with the given parameters to + * *addr and *addr_len. On error, do not change *addr and return nonzero. + */ +int osmo_sockaddr_init(struct sockaddr_storage *addr, socklen_t *addr_len, + uint16_t family, uint16_t type, uint8_t proto, + const char *host, uint16_t port) +{ + struct addrinfo *res; + int rc; + rc = _osmo_getaddrinfo(&res, family, type, proto, host, port); + + if (rc != 0) { + LOGERR("getaddrinfo returned error %d\n", (int)rc); + return -EINVAL; + } + + OSMO_ASSERT(res->ai_addrlen <= sizeof(*addr)); + memcpy(addr, res->ai_addr, res->ai_addrlen); + *addr_len = res->ai_addrlen; + freeaddrinfo(res); + + return 0; +} + + +void *tall_bsc_ctx; + +const char *gtphub_copyright = + "Copyright (C) 2015 sysmocom s.m.f.c GmbH info@sysmocom.de\r\n" + "License AGPLv3+: GNU AGPL version 2 or later http://gnu.org/licenses/agpl-3.0.html\r\n" + "This is free software: you are free to change and redistribute it.\r\n" + "There is NO WARRANTY, to the extent permitted by law.\r\n"; + +static struct log_info_cat gtphub_categories[] = { + [DGTPHUB] = { + .name = "DGTPHUB", + .description = "GTP Hub", + .color = "\033[1;33m", + .enabled = 1, .loglevel = LOGL_NOTICE, + }, +}; + +int gtphub_log_filter_fn(const struct log_context *ctx, + struct log_target *tar) +{ + return 0; +} + +static const struct log_info gtphub_log_info = { + .filter_fn = gtphub_log_filter_fn, + .cat = gtphub_categories, + .num_cat = ARRAY_SIZE(gtphub_categories), +}; + +/* Recv datagram from from->fd, optionally write sender's address to *from_addr + * and *from_addr_len, parse datagram as GTP, and forward on to to->fd using + * *to_addr. to_addr may be NULL, if an address is set on to->fd. */ +int gtp_relay(struct osmo_fd *from, struct sockaddr_storage *from_addr, socklen_t *from_addr_len, + struct osmo_fd *to, struct sockaddr_storage *to_addr, socklen_t to_addr_len) +{ + static uint8_t buf[4096]; + + errno = 0; + ssize_t received = recvfrom(from->fd, buf, sizeof(buf), 0, + (struct sockaddr*)from_addr, from_addr_len); + + if (received <= 0) { + if (errno != EAGAIN) + LOGERR("error: %s\n", strerror(errno)); + return -errno; + } + + if (from_addr) { + LOG("from %s\n", osmo_hexdump((uint8_t*)from_addr, *from_addr_len)); + } + + if (received <= 0) { + LOGERR("error: %s\n", strerror(errno)); + return -EINVAL; + } + + /* insert magic here */ + + errno = 0; + ssize_t sent = sendto(to->fd, buf, received, 0, + (struct sockaddr*)to_addr, to_addr_len); + + if (to_addr) { + LOG("to %s\n", osmo_hexdump((uint8_t*)to_addr, to_addr_len)); + } + + if (sent == -1) { + LOGERR("error: %s\n", strerror(errno)); + return -EINVAL; + } + + if (sent != received) + LOGERR("sent(%d) != received(%d)\n", (int)sent, (int)received); + else + LOG("%d b ok\n", (int)sent); + + return 0; +} + +struct sockaddr_storage last_client_addr; +socklen_t last_client_addr_len; +struct sockaddr_storage server_addr; +socklen_t server_addr_len; + +int clients_read_cb(struct osmo_fd *clients_ofd, unsigned int what) +{ + LOG("reading from clients socket\n"); + struct osmo_fd *server_ofd = clients_ofd->data; + + if (!(what & BSC_FD_READ)) + return 0; + + last_client_addr_len = sizeof(last_client_addr); + return gtp_relay(clients_ofd, &last_client_addr, &last_client_addr_len, + server_ofd, &server_addr, server_addr_len); +} + +int server_read_cb(struct osmo_fd *server_ofd, unsigned int what) +{ + LOG("reading from server socket\n"); + struct osmo_fd *clients_ofd = server_ofd->data; + + if (!(what & BSC_FD_READ)) + return 0; + + return gtp_relay(server_ofd, NULL, NULL, + clients_ofd, &last_client_addr, last_client_addr_len); +} + +int main(int argc, char **argv) +{ + osmo_init_logging(&gtphub_log_info); + + int rc; + + const char* clients_addr_str = "localhost"; + uint16_t clients_port = 3386; + + const char* server_addr_str = "localhost"; + uint16_t server_port = 1234; + + /* Which local interface to use to listen for the GTP server's + * responses */ + const char* server_rx_addr_str = "localhost"; + uint16_t server_rx_port = 4321; + + rc = osmo_sockaddr_init(&server_addr, &server_addr_len, + AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, server_addr_str, server_port); + if (rc != 0) { + LOGERR("Cannot resolve '%s port %d'\n", server_addr_str, server_port); + exit(-1); + } + + struct osmo_fd clients_ofd; + struct osmo_fd server_ofd; + + memset(&clients_ofd, 0, sizeof(clients_ofd)); + clients_ofd.when = BSC_FD_READ; + clients_ofd.cb = clients_read_cb; + clients_ofd.data = &server_ofd; + + rc = osmo_sock_init_ofd(&clients_ofd, AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, clients_addr_str, clients_port, OSMO_SOCK_F_BIND); + if (rc < 1) { + LOGERR("Cannot bind to %s port %d\n", clients_addr_str, clients_port); + exit(-1); + } + + memset(&server_ofd, 0, sizeof(server_ofd)); + server_ofd.when = BSC_FD_READ; + server_ofd.cb = server_read_cb; + server_ofd.data = &clients_ofd; + + rc = osmo_sock_init_ofd(&server_ofd, AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, server_rx_addr_str, server_rx_port, OSMO_SOCK_F_BIND); + if (rc < 1) { + LOGERR("Cannot bind to %s port %d\n", server_rx_addr_str, server_rx_port); + exit(-1); + } + + LOG("GTP server connection: %s port %d <--> %s port %d\n", + server_rx_addr_str, (int)server_rx_port, + server_addr_str, (int)server_port); + LOG("Listening for clients on %s port %d.\n", clients_addr_str, clients_port); + + int daemonize = 0; + + if (daemonize) { + rc = osmo_daemonize(); + if (rc < 0) { + LOGERR("Error during daemonize"); + exit(1); + } + } + + while (1) { + rc = osmo_select_main(0); + if (rc < 0) + exit(3); + } + + /* not reached */ + exit(0); +}

Sponsored-by: On-Waves ehf

create mode 100644 openbsc/include/openbsc/gtphub.h create mode 100644 openbsc/src/gprs/gtphub.c

diff --git a/openbsc/include/openbsc/Makefile.am b/openbsc/include/openbsc/Makefile.am index 254f43d..c5dd6af 100644 --- a/openbsc/include/openbsc/Makefile.am +++ b/openbsc/include/openbsc/Makefile.am @@ -16,7 +16,8 @@ noinst_HEADERS = abis_nm.h abis_rsl.h db.h gsm_04_08.h gsm_data.h \ arfcn_range_encode.h nat_rewrite_trie.h bsc_nat_callstats.h \ osmux.h mgcp_transcode.h gprs_utils.h \ gprs_gb_parse.h smpp.h meas_feed.h gprs_gsup_messages.h \ - gprs_gsup_client.h bsc_msg_filter.h + gprs_gsup_client.h bsc_msg_filter.h \ + gtphub.h

openbsc_HEADERS = gsm_04_08.h meas_rep.h bsc_api.h openbscdir = $(includedir)/openbsc diff --git a/openbsc/include/openbsc/gtphub.h b/openbsc/include/openbsc/gtphub.h new file mode 100644 index 0000000..7c89db1 --- /dev/null +++ b/openbsc/include/openbsc/gtphub.h @@ -0,0 +1,96 @@ +/* GTP Hub Implementation */ + +/* (C) 2015 by sysmocom s.f.m.c. GmbH info@sysmocom.de + * All Rights Reserved + * + * Author: Neels Hofmeyr + * + * 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 http://www.gnu.org/licenses/. + */ + +#pragma once + +#include <stdint.h> +#include <sys/socket.h> + +#include <osmocom/core/select.h> + + +/* general */ + +enum gtphub_port_idx { + GTPH_PORT_CONTROL = 0, + GTPH_PORT_USER = 1, + GTPH_PORT_N +}; + +extern const char* const gtphub_port_idx_names[GTPH_PORT_N]; + + +/* config */ + +struct gtphub_cfg_addr { + const char *addr_str; + uint16_t port; +}; + +struct gtphub_cfg_bind { + struct gtphub_cfg_addr bind; +}; + +struct gtphub_cfg { + struct gtphub_cfg_bind to_sgsns[GTPH_PORT_N]; + struct gtphub_cfg_bind to_ggsns[GTPH_PORT_N]; +}; + + +/* state */ + +struct gtphub_addr { + struct sockaddr_storage a; + socklen_t l; +}; + +struct gtphub_peer { + struct llist_head entry; + + struct gtphub_addr addr; +}; + +struct gtphub_bind { + struct osmo_fd ofd; + + /* list of struct gtphub_peer */ + struct llist_head peers; +}; + +struct gtphub { + struct gtphub_bind to_sgsns[GTPH_PORT_N]; + struct gtphub_bind to_ggsns[GTPH_PORT_N]; +}; + + +/* api */ + +void gtphub_zero(struct gtphub *hub); +int gtphub_init(struct gtphub *hub, struct gtphub_cfg *cfg); + +/* Create a new gtphub_peer instance added to peers_list. + * Initialize to all-zero. Return a pointer to the new instance, or NULL on + * error. */ +struct gtphub_peer *gtphub_peer_new(struct gtphub_bind *bind); + +/* Remove a gtphub_peer from its list and free it. */ +void gtphub_peer_del(struct gtphub_peer *peer); + diff --git a/openbsc/src/gprs/Makefile.am b/openbsc/src/gprs/Makefile.am index 66d0625..f2f914d 100644 --- a/openbsc/src/gprs/Makefile.am +++ b/openbsc/src/gprs/Makefile.am @@ -34,5 +34,5 @@ osmo_sgsn_LDADD = \ -lgtp $(OSMO_LIBS) $(LIBOSMOABIS_LIBS) $(LIBCARES_LIBS) \ $(LIBCRYPTO_LIBS) -lrt

-osmo_gtphub_SOURCES = gtphub_main.c +osmo_gtphub_SOURCES = gtphub_main.c gtphub.c osmo_gtphub_LDADD = $(LIBOSMOCORE_LIBS) -lrt diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c new file mode 100644 index 0000000..ffe0d4a --- /dev/null +++ b/openbsc/src/gprs/gtphub.c @@ -0,0 +1,45 @@ +/* GTP Hub Implementation */ + +/* (C) 2015 by sysmocom s.f.m.c. GmbH info@sysmocom.de + * All Rights Reserved + * + * Author: Neels Hofmeyr + * + * 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 http://www.gnu.org/licenses/. + */ + +#include <string.h> + +#include <openbsc/gtphub.h> +#include <openbsc/debug.h> + +#include <osmocom/core/utils.h> +#include <osmocom/core/logging.h> + +void *osmo_gtphub_ctx; + +#define LOGERR(fmt, args...) \ + LOGP(DGTPHUB, LOGL_ERROR, fmt, ##args) + +void gtphub_zero(struct gtphub *hub) +{ + memset(hub, '\0', sizeof(*hub)); +} + +int gtphub_init(struct gtphub *hub, struct gtphub_cfg *cfg) +{ + LOGERR("%s not implemented\n", __func__); + return -1; +} +

diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index 97e52a6..577a2d0 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -119,6 +119,8 @@ static int gtp_relay(struct osmo_fd *from, errno = 0; ssize_t received = recvfrom(from->fd, buf, sizeof(buf), 0, (struct sockaddr*)from_addr, from_addr_len); + /* TODO use recvmsg and get a MSG_TRUNC flag to make sure the message + * is not truncated. Then maybe reduce buf's size. */

if (received <= 0) { if (errno != EAGAIN)

Sponsored-by: On-Waves ehi

create mode 100644 openbsc/tests/gtphub/Makefile.am create mode 100644 openbsc/tests/gtphub/gtphub_test.c create mode 100644 openbsc/tests/gtphub/gtphub_test.ok

diff --git a/openbsc/.gitignore b/openbsc/.gitignore index f024d76..bf05ac2 100644 --- a/openbsc/.gitignore +++ b/openbsc/.gitignore @@ -78,6 +78,7 @@ tests/trau/trau_test tests/mgcp/mgcp_transcoding_test tests/sgsn/sgsn_test tests/subscr/subscr_test +tests/gtphub/gtphub_test

tests/atconfig tests/atlocal diff --git a/openbsc/configure.ac b/openbsc/configure.ac index fc30b5e..9393282 100644 --- a/openbsc/configure.ac +++ b/openbsc/configure.ac @@ -209,6 +209,7 @@ AC_OUTPUT( tests/trau/Makefile tests/sgsn/Makefile tests/subscr/Makefile + tests/gtphub/Makefile doc/Makefile doc/examples/Makefile Makefile) diff --git a/openbsc/tests/Makefile.am b/openbsc/tests/Makefile.am index 773830b..7dda124 100644 --- a/openbsc/tests/Makefile.am +++ b/openbsc/tests/Makefile.am @@ -1,4 +1,4 @@ -SUBDIRS = gsm0408 db channel mgcp gprs abis gbproxy trau subscr +SUBDIRS = gsm0408 db channel mgcp gprs abis gbproxy trau subscr gtphub

if BUILD_NAT SUBDIRS += bsc-nat bsc-nat-trie diff --git a/openbsc/tests/gtphub/Makefile.am b/openbsc/tests/gtphub/Makefile.am new file mode 100644 index 0000000..7cc3ac9 --- /dev/null +++ b/openbsc/tests/gtphub/Makefile.am @@ -0,0 +1,14 @@ +AM_CPPFLAGS = $(all_includes) -I$(top_srcdir)/include +AM_CFLAGS=-Wall -ggdb3 $(LIBOSMOCORE_CFLAGS) + +EXTRA_DIST = \ + gtphub_test.ok + +noinst_PROGRAMS = gtphub_test + +gtphub_test_SOURCES = gtphub_test.c + +gtphub_test_LDADD = \ + $(LIBOSMOCORE_LIBS) \ + -lgtp -lrt + diff --git a/openbsc/tests/gtphub/gtphub_test.c b/openbsc/tests/gtphub/gtphub_test.c new file mode 100644 index 0000000..95f82c3 --- /dev/null +++ b/openbsc/tests/gtphub/gtphub_test.c @@ -0,0 +1,63 @@ +/* Test the GTP hub */ + +/* (C) 2015 by sysmocom s.f.m.c. GmbH + * All Rights Reserved + * + * Author: Neels Hofmeyr nhofmeyr@sysmcom.de + * + * 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 http://www.gnu.org/licenses/. + * + */ + +#include <stdio.h> + +#include <osmocom/core/utils.h> +#include <osmocom/core/msgb.h> +#include <osmocom/core/application.h> + +#include <openbsc/debug.h> + +void *osmo_gtphub_ctx; + +static void test_gtphub_api(void) +{ + OSMO_ASSERT(1); +} + +static struct log_info_cat gtphub_categories[] = { + [DGTPHUB] = { + .name = "DGTPHUB", + .description = "GTP Hub", + .color = "\033[1;33m", + .enabled = 1, .loglevel = LOGL_NOTICE, + }, +}; + +static struct log_info info = { + .cat = gtphub_categories, + .num_cat = ARRAY_SIZE(gtphub_categories), +}; + +int main(int argc, char **argv) +{ + osmo_init_logging(&info); + osmo_gtphub_ctx = talloc_named_const(NULL, 0, "osmo_gtphub"); + + test_gtphub_api(); + printf("Done\n"); + + talloc_report_full(osmo_gtphub_ctx, stderr); + return 0; +} + diff --git a/openbsc/tests/gtphub/gtphub_test.ok b/openbsc/tests/gtphub/gtphub_test.ok new file mode 100644 index 0000000..a965a70 --- /dev/null +++ b/openbsc/tests/gtphub/gtphub_test.ok @@ -0,0 +1 @@ +Done diff --git a/openbsc/tests/testsuite.at b/openbsc/tests/testsuite.at index 74aaef0..bfaa76e 100644 --- a/openbsc/tests/testsuite.at +++ b/openbsc/tests/testsuite.at @@ -103,3 +103,10 @@ AT_CHECK([test "$enable_sgsn_test" != no || exit 77]) cat $abs_srcdir/sgsn/sgsn_test.ok > expout AT_CHECK([$abs_top_builddir/tests/sgsn/sgsn_test], [], [expout], [ignore]) AT_CLEANUP + +AT_SETUP([gtphub]) +AT_KEYWORDS([gtphub]) +AT_CHECK([test "$enable_gtphub_test" != no || exit 77]) +cat $abs_srcdir/gtphub/gtphub_test.ok > expout +AT_CHECK([$abs_top_builddir/tests/gtphub/gtphub_test], [], [expout], [ignore]) +AT_CLEANUP

Sponsored-by: On-Waves ehi

diff --git a/openbsc/src/gprs/Makefile.am b/openbsc/src/gprs/Makefile.am index f2f914d..d571d8d 100644 --- a/openbsc/src/gprs/Makefile.am +++ b/openbsc/src/gprs/Makefile.am @@ -35,4 +35,4 @@ osmo_sgsn_LDADD = \ $(LIBCRYPTO_LIBS) -lrt

osmo_gtphub_SOURCES = gtphub_main.c gtphub.c -osmo_gtphub_LDADD = $(LIBOSMOCORE_LIBS) -lrt +osmo_gtphub_LDADD = -lgtp $(LIBOSMOCORE_LIBS) -lrt diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index a80243c..208b623 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -24,6 +24,8 @@ #include <inttypes.h> #include <netinet/in.h>

+#include <gtp.h> + #include <openbsc/gtphub.h> #include <openbsc/debug.h>

@@ -46,6 +48,150 @@ typedef int (*osmo_fd_cb_t)(struct osmo_fd *fd, unsigned int what); #define __llist_first(head) (((head)->next == (head)) ? NULL : (head)->next) #define llist_first(head, type, entry) llist_entry(__llist_first(head), type, entry)

+/* TODO duplicated from openggsn/gtp/gtpie.h */ +#define ntoh16(x) ntohs(x) +#define ntoh32(x) ntohl(x) + +/* TODO move GTP header stuff to openggsn/gtp/ ? See gtp_decaps*() */ + +enum gtp_rc { + GTP_RC_UNKNOWN = 0, + GTP_RC_TINY = 1, /* no IEs (like ping/pong) */ + GTP_RC_PDU = 2, /* a real packet with IEs */ + + GTP_RC_TOOSHORT = -1, + GTP_RC_UNSUPPORTED_VERSION = -2, + GTP_RC_INVALID_IE = -3, +}; + +struct gtp_packet_desc { + const union gtp_packet *data; + int data_len; + int header_len; + int version; + int rc; +}; + +/* Validate GTP version 0 data; analogous to validate_gtp1_header(), see there. + */ +void validate_gtp0_header(struct gtp_packet_desc *p) +{ + const struct gtp0_header *pheader = &(p->data->gtp0.h); + p->rc = GTP_RC_UNKNOWN; + p->header_len = 0; + + OSMO_ASSERT(p->data_len >= 1); + OSMO_ASSERT(p->version == 0); + + if (p->data_len < GTP0_HEADER_SIZE) { + LOGERR("GTP0 packet too short: %d\n", p->data_len); + p->rc = GTP_RC_TOOSHORT; + return; + } + + if (p->data_len == GTP0_HEADER_SIZE) { + p->rc = GTP_RC_TINY; + p->header_len = GTP0_HEADER_SIZE; + return; + } + + /* Check packet length field versus length of packet */ + if (p->data_len != (ntoh16(pheader->length) + GTP0_HEADER_SIZE)) { + LOGERR("GTP packet length field (%d + %d) does not match" + " actual length (%d)\n", + GTP0_HEADER_SIZE, (int)ntoh16(pheader->length), + p->data_len); + p->rc = GTP_RC_TOOSHORT; + return; + } + + p->header_len = GTP0_HEADER_SIZE; + p->rc = GTP_RC_PDU; +} + +/* Validate GTP version 1 data, and update p->rc with the result, as well as + * p->header_len in case of a valid header. */ +void validate_gtp1_header(struct gtp_packet_desc *p) +{ + const struct gtp1_header_long *pheader = &(p->data->gtp1l.h); + p->rc = GTP_RC_UNKNOWN; + p->header_len = 0; + + OSMO_ASSERT(p->data_len >= 1); + OSMO_ASSERT(p->version == 1); + + if ((p->data_len < GTP1_HEADER_SIZE_LONG) + && (p->data_len != GTP1_HEADER_SIZE_SHORT)){ + LOGERR("GTP packet too short: %d\n", p->data_len); + p->rc = GTP_RC_TOOSHORT; + return; + } + + if (p->data_len <= GTP1_HEADER_SIZE_LONG) { + p->rc = GTP_RC_TINY; + p->header_len = GTP1_HEADER_SIZE_SHORT; + return; + } + + /* Check packet length field versus length of packet */ + if (p->data_len != (ntoh16(pheader->length) + GTP1_HEADER_SIZE_SHORT)) { + LOGERR("GTP packet length field (%d + %d) does not match" + " actual length (%d)\n", + GTP1_HEADER_SIZE_SHORT, (int)ntoh16(pheader->length), + p->data_len); + p->rc = GTP_RC_TOOSHORT; + return; + } + + p->rc = GTP_RC_PDU; + p->header_len = GTP1_HEADER_SIZE_LONG; +} + +/* Examine whether p->data of size p->data_len has a valid GTP header. Set + * p->version, p->rc and p->header_len. On error, p->rc <= 0 (see enum + * gtp_rc). p->data must point at a buffer with p->data_len set. */ +void validate_gtp_header(struct gtp_packet_desc *p) +{ + p->rc = GTP_RC_UNKNOWN; + + /* Need at least 1 byte in order to check version */ + if (p->data_len < (1)) { + LOGERR("Discarding packet - too small\n"); + p->rc = GTP_RC_TOOSHORT; + return; + } + + p->version = p->data->flags >> 5; + + switch (p->version) { + case 0: + validate_gtp0_header(p); + break; + case 1: + validate_gtp1_header(p); + break; + default: + LOGERR("Unsupported GTP version: %d\n", p->version); + p->rc = GTP_RC_UNSUPPORTED_VERSION; + break; + } +} + +/* Validate header, and index information elements. Write decoded packet + * information to *res. res->data will point at the given data buffer. On + * error, p->rc is set <= 0 (see enum gtp_rc). */ +static void gtp_decode(const uint8_t *data, int data_len, struct gtp_packet_desc *res) +{ + memset(res, '\0', sizeof(*res)); + res->data = (union gtp_packet*)data; + res->data_len = data_len; + + validate_gtp_header(res); + + if (res->rc == GTP_RC_TINY) + LOG("tiny: no IEs in this GTP packet\n"); +} +

/* general */

@@ -55,6 +201,8 @@ const char* const gtphub_port_idx_names[GTPH_PORT_N] = { };

+/* tei_map, tei_pool */ + void tei_pool_init(struct tei_pool *pool) { *pool = (struct tei_pool){}; @@ -217,6 +365,17 @@ static int gtp_relay(struct osmo_fd *from,

/* insert magic here */

+ struct gtp_packet_desc p; + gtp_decode(buf, received, &p); + + if (p.rc > 0) + LOG("Valid GTP header (v%d)\n", p.version); +#if 0 + else + // error has been logged + return 0; +#endif + errno = 0; ssize_t sent = sendto(to->fd, buf, received, 0, (struct sockaddr*)to_addr, to_addr_len);

Sponsored-by: On-Waves ehi

diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index 1d9c6d5..e849a8f 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -107,6 +107,7 @@ void validate_gtp0_header(struct gtp_packet_desc *p) return; }

+ LOG("GTP v0 TID = %" PRIu64 "\n", pheader->tid); p->header_len = GTP0_HEADER_SIZE; p->rc = GTP_RC_PDU; } @@ -129,6 +130,20 @@ void validate_gtp1_header(struct gtp_packet_desc *p) return; }

+ LOG("|GTPv1\n"); + LOG("| type = %" PRIu8 " 0x%02" PRIx8 "\n", + pheader->type, pheader->type); + LOG("| length = %" PRIu16 " 0x%04" PRIx16 "\n", + ntoh16(pheader->length), ntoh16(pheader->length)); + LOG("| TEI = %" PRIu32 " 0x%08" PRIx32 "\n", + ntoh32(pheader->tei), ntoh32(pheader->tei)); + LOG("| seq = %" PRIu16 " 0x%04" PRIx16 "\n", + ntoh16(pheader->seq), ntoh16(pheader->seq)); + LOG("| npdu = %" PRIu8 " 0x%02" PRIx8 "\n", + pheader->npdu, pheader->npdu); + LOG("| next = %" PRIu8 " 0x%02" PRIx8 "\n", + pheader->next, pheader->next); + if (p->data_len <= GTP1_HEADER_SIZE_LONG) { p->rc = GTP_RC_TINY; p->header_len = GTP1_HEADER_SIZE_SHORT; @@ -366,6 +381,7 @@ static int gtp_relay(struct osmo_fd *from, }

/* insert magic here */ + LOG("Received %d\n%s\n", (int)received, osmo_hexdump(buf, received));

struct gtp_packet_desc p; gtp_decode(buf, received, &p); @@ -403,7 +419,7 @@ int from_ggsns_read_cb(struct osmo_fd *from_ggsns_ofd, unsigned int what) { unsigned int port_idx = from_ggsns_ofd->priv_nr; OSMO_ASSERT(port_idx < GTPH_PORT_N); - LOG("reading from GGSN (%s)\n", gtphub_port_idx_names[port_idx]); + LOG("\n\n=== reading from GGSN (%s)\n", gtphub_port_idx_names[port_idx]); if (!(what & BSC_FD_READ)) return 0;

@@ -426,7 +442,7 @@ int from_sgsns_read_cb(struct osmo_fd *from_sgsns_ofd, unsigned int what) { unsigned int port_idx = from_sgsns_ofd->priv_nr; OSMO_ASSERT(port_idx < GTPH_PORT_N); - LOG("reading from SGSN (%s)\n", gtphub_port_idx_names[port_idx]); + LOG("\n\n=== reading from SGSN (%s)\n", gtphub_port_idx_names[port_idx]);

if (!(what & BSC_FD_READ)) return 0; diff --git a/openbsc/src/gprs/gtphub_main.c b/openbsc/src/gprs/gtphub_main.c index b43e28d..f3237fe 100644 --- a/openbsc/src/gprs/gtphub_main.c +++ b/openbsc/src/gprs/gtphub_main.c @@ -200,6 +200,7 @@ int main(int argc, char **argv) LOGERR("Cannot resolve '%s port %d'\n", ggsn_addr_str, ggsn_port); exit(-1); } + LOG("DEBUG: using GGSN %s port %d\n", ggsn_addr_str, ggsn_port);

log_cfg(cfg);

diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index 73e7c02..9f3e021 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -265,6 +265,9 @@ static void gtp_decode(const uint8_t *data, int data_len, struct gtp_packet_desc

validate_gtp_header(res);

+ if (res->rc > 0) + LOG("Valid GTP header (v%d)\n", res->version); + if (res->rc == GTP_RC_TINY) LOG("tiny: no IEs in this GTP packet\n");

@@ -441,23 +444,20 @@ static int gtphub_gtp_bind_init(struct gtphub_bind *b, }

/* Recv datagram from from->fd, optionally write sender's address to *from_addr - * and *from_addr_len, parse datagram as GTP, and forward on to to->fd using - * *to_addr. to_addr may be NULL, if an address is set on to->fd. */ -static int gtp_relay(struct osmo_fd *from, - struct sockaddr_storage *from_addr, - socklen_t *from_addr_len, - struct osmo_fd *to, - struct sockaddr_storage *to_addr, - socklen_t to_addr_len) + * and *from_addr_len. Return the number of bytes read. */ +/* Send datagram to to->fd using *to_addr. to_addr may be NULL, if an address + * is set on to->fd. */ +static int gtphub_read(struct osmo_fd *from, + struct sockaddr_storage *from_addr, + socklen_t *from_addr_len, + uint8_t *buf, size_t buf_len) { - static uint8_t buf[4096]; - /* recvfrom requires the available length to be set in *from_addr_len. */ if (from_addr_len && from_addr) *from_addr_len = sizeof(*from_addr);

errno = 0; - ssize_t received = recvfrom(from->fd, buf, sizeof(buf), 0, + ssize_t received = recvfrom(from->fd, buf, buf_len, 0, (struct sockaddr*)from_addr, from_addr_len); /* TODO use recvmsg and get a MSG_TRUNC flag to make sure the message * is not truncated. Then maybe reduce buf's size. */ @@ -465,7 +465,7 @@ static int gtp_relay(struct osmo_fd *from, if (received <= 0) { if (errno != EAGAIN) LOGERR("error: %s\n", strerror(errno)); - return -errno; + return 0; }

if (from_addr) { @@ -474,25 +474,20 @@ static int gtp_relay(struct osmo_fd *from,

if (received <= 0) { LOGERR("error: %s\n", strerror(errno)); - return -EINVAL; + return 0; }

- /* insert magic here */ LOG("Received %d\n%s\n", (int)received, osmo_hexdump(buf, received)); + return received; +}

- struct gtp_packet_desc p; - gtp_decode(buf, received, &p); - - if (p.rc > 0) - LOG("Valid GTP header (v%d)\n", p.version); -#if 0 - else - // error has been logged - return 0; -#endif - +static int gtphub_write(struct osmo_fd *to, + struct sockaddr_storage *to_addr, + socklen_t to_addr_len, + uint8_t *buf, size_t buf_len) +{ errno = 0; - ssize_t sent = sendto(to->fd, buf, received, 0, + ssize_t sent = sendto(to->fd, buf, buf_len, 0, (struct sockaddr*)to_addr, to_addr_len);

if (to_addr) { @@ -504,8 +499,8 @@ static int gtp_relay(struct osmo_fd *from, return -EINVAL; }

- if (sent != received) - LOGERR("sent(%d) != received(%d)\n", (int)sent, (int)received); + if (sent != buf_len) + LOGERR("sent(%d) != data_len(%d)\n", (int)sent, (int)buf_len); else LOG("%d b ok\n", (int)sent);

@@ -530,9 +525,23 @@ int from_ggsns_read_cb(struct osmo_fd *from_ggsns_ofd, unsigned int what) return 0; }

- return gtp_relay(from_ggsns_ofd, NULL, NULL, - &hub->to_sgsns[port_idx].ofd, - &sgsn->addr.a, sgsn->addr.l); + static uint8_t buf[4096]; + size_t received = gtphub_read(from_ggsns_ofd, NULL, NULL, + buf, sizeof(buf)); + if (received < 1) + return 0; + + static struct gtp_packet_desc p; + gtp_decode(buf, received, &p); + +#if 0 + if (p.rc <= 0) + return 0; +#endif + + return gtphub_write(&hub->to_sgsns[port_idx].ofd, + &sgsn->addr.a, sgsn->addr.l, + (uint8_t*)p.data, p.data_len); }

int from_sgsns_read_cb(struct osmo_fd *from_sgsns_ofd, unsigned int what) @@ -560,9 +569,23 @@ int from_sgsns_read_cb(struct osmo_fd *from_sgsns_ofd, unsigned int what) if (!sgsn) sgsn = gtphub_peer_new(&hub->to_sgsns[port_idx]);

- return gtp_relay(from_sgsns_ofd, &sgsn->addr.a, &sgsn->addr.l, - &hub->to_ggsns[port_idx].ofd, - &ggsn->addr.a, ggsn->addr.l); + static uint8_t buf[4096]; + size_t received = gtphub_read(from_sgsns_ofd, &sgsn->addr.a, &sgsn->addr.l, + buf, sizeof(buf)); + if (received < 1) + return 0; + + static struct gtp_packet_desc p; + gtp_decode(buf, received, &p); + +#if 0 + if (p.rc <= 0) + return 0; +#endif + + return gtphub_write(&hub->to_ggsns[port_idx].ofd, + &ggsn->addr.a, ggsn->addr.l, + (uint8_t*)p.data, p.data_len); }

int gtphub_init(struct gtphub *hub, struct gtphub_cfg *cfg)

diff --git a/openbsc/src/gprs/gtphub_main.c b/openbsc/src/gprs/gtphub_main.c index f3237fe..509c49f 100644 --- a/openbsc/src/gprs/gtphub_main.c +++ b/openbsc/src/gprs/gtphub_main.c @@ -19,12 +19,15 @@ * along with this program. If not, see http://www.gnu.org/licenses/. */

+#include <unistd.h> +#include <signal.h> #include <string.h> #include <errno.h>

#define _GNU_SOURCE #include <getopt.h>

+#include <osmocom/core/signal.h> #include <osmocom/core/application.h> #include <osmocom/core/logging.h> #include <osmocom/core/utils.h> @@ -148,10 +151,38 @@ void log_cfg(struct gtphub_cfg *cfg) a->addr_str, a->port); }

+static void signal_handler(int signal) +{ + fprintf(stdout, "signal %u received\n", signal); + + switch (signal) { + case SIGINT: + osmo_signal_dispatch(SS_L_GLOBAL, S_L_GLOBAL_SHUTDOWN, NULL); + sleep(1); + exit(0); + break; + case SIGABRT: + /* in case of abort, we want to obtain a talloc report + * and then return to the caller, who will abort the process */ + case SIGUSR1: + case SIGUSR2: + talloc_report_full(osmo_gtphub_ctx, stderr); + break; + default: + break; + } +} + int main(int argc, char **argv) { osmo_gtphub_ctx = talloc_named_const(NULL, 0, "osmo_gtphub");

+ signal(SIGINT, &signal_handler); + signal(SIGABRT, &signal_handler); + signal(SIGUSR1, &signal_handler); + signal(SIGUSR2, &signal_handler); + osmo_init_ignore_signals(); + osmo_init_logging(&gtphub_log_info);

int rc;