Add program osmo-gtphub from gtphub_main.c to Makefile.am. Add osmo-gtphub binary to gitignore. Sponsored-by: On-Waves ehf diff --git a/openbsc/.gitignore b/openbsc/.gitignore index 2210c47..f024d76 100644 --- a/openbsc/.gitignore +++ b/openbsc/.gitignore @@ -53,6 +53,7 @@ src/utils/isdnsync src/nat/bsc_nat src/gprs/osmo-sgsn src/gprs/osmo-gbproxy +src/gprs/osmo-gtphub src/osmo-bsc_nat/osmo-bsc_nat #tests diff --git a/openbsc/src/gprs/Makefile.am b/openbsc/src/gprs/Makefile.am index f012003..66d0625 100644 --- a/openbsc/src/gprs/Makefile.am +++ b/openbsc/src/gprs/Makefile.am @@ -11,6 +11,7 @@ noinst_HEADERS = gprs_sndcp.h bin_PROGRAMS = osmo-gbproxy if HAVE_LIBGTP +bin_PROGRAMS += osmo-gtphub if HAVE_LIBCARES bin_PROGRAMS += osmo-sgsn endif @@ -32,3 +33,6 @@ osmo_sgsn_LDADD = \ $(top_builddir)/src/libcommon/libcommon.a \ -lgtp $(OSMO_LIBS) $(LIBOSMOABIS_LIBS) $(LIBCARES_LIBS) \ $(LIBCRYPTO_LIBS) -lrt + +osmo_gtphub_SOURCES = gtphub_main.c +osmo_gtphub_LDADD = $(LIBOSMOCORE_LIBS) -lrt -- 2.1.4

Sponsored-by: On-Waves ehi diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index ffe0d4a..97e52a6 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -20,26 +20,231 @@ */ #include <string.h> +#include <errno.h> +#include <netinet/in.h> #include <openbsc/gtphub.h> #include <openbsc/debug.h> #include <osmocom/core/utils.h> #include <osmocom/core/logging.h> +#include <osmocom/core/socket.h> void *osmo_gtphub_ctx; #define LOGERR(fmt, args...) \ LOGP(DGTPHUB, LOGL_ERROR, fmt, ##args) +#define LOG(fmt, args...) \ + LOGP(DGTPHUB, LOGL_NOTICE, fmt, ##args) + +/* TODO move this to osmocom/core/select.h ? */ +typedef int (*osmo_fd_cb_t)(struct osmo_fd *fd, unsigned int what); + +/* TODO move this to osmocom/core/linuxlist.h ? */ +#define __llist_first(head) (((head)->next == (head)) ? NULL : (head)->next) +#define llist_first(head, type, entry) llist_entry(__llist_first(head), type, entry) + + +/* general */ + +const char* const gtphub_port_idx_names[GTPH_PORT_N] = { + "CTRL", + "USER", +}; + + +/* gtphub */ + void gtphub_zero(struct gtphub *hub) { memset(hub, '\0', sizeof(*hub)); } +static int gtphub_sock_init(struct osmo_fd *ofd, + const struct gtphub_cfg_addr *addr, + osmo_fd_cb_t cb, + void *data, + int ofd_id) +{ + ofd->when = BSC_FD_READ; + ofd->cb = cb; + ofd->data = data; + ofd->priv_nr = ofd_id; + + int rc; + rc = osmo_sock_init_ofd(ofd, + AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, + addr->addr_str, addr->port, + OSMO_SOCK_F_BIND); + if (rc < 1) { + LOGERR("Cannot bind to %s port %d (rc %d)\n", + addr->addr_str, (int)addr->port, rc); + return -1; + } + + return 0; +} + +static int gtphub_gtp_bind_init(struct gtphub_bind *b, + const struct gtphub_cfg_bind *cfg, + osmo_fd_cb_t cb, void *cb_data, + unsigned int ofd_id) +{ + memset(b, '\0', sizeof(*b)); + + INIT_LLIST_HEAD(&b->peers); + + if (gtphub_sock_init(&b->ofd, &cfg->bind, cb, cb_data, ofd_id) != 0) + return -1; + return 0; +} + +/* 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) +{ + 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, + (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; +} + +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]); + if (!(what & BSC_FD_READ)) + return 0; + + struct gtphub *hub = from_ggsns_ofd->data; + + /* TODO this will not be hardcoded. */ + struct gtphub_peer *sgsn = llist_first(&hub->to_sgsns[port_idx].peers, + struct gtphub_peer, entry); + if (!sgsn) { + LOGERR("no sgsn"); + return 0; + } + + return gtp_relay(from_ggsns_ofd, NULL, NULL, + &hub->to_sgsns[port_idx].ofd, + &sgsn->addr.a, sgsn->addr.l); +} + +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]); + + if (!(what & BSC_FD_READ)) + return 0; + + struct gtphub *hub = from_sgsns_ofd->data; + + /* TODO this will not be hardcoded. */ + struct gtphub_peer *ggsn = llist_first(&hub->to_ggsns[port_idx].peers, + struct gtphub_peer, entry); + if (!ggsn) { + LOGERR("no ggsn to send to\n"); + return 0; + } + + /* so far just remembering the last sgsn */ + struct gtphub_peer *sgsn = llist_first(&hub->to_sgsns[port_idx].peers, + struct gtphub_peer, entry); + 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); +} + int gtphub_init(struct gtphub *hub, struct gtphub_cfg *cfg) { - LOGERR("%s not implemented\n", __func__); - return -1; + gtphub_zero(hub); + + int port_id; + for (port_id = 0; port_id < GTPH_PORT_N; port_id++) { + int rc; + rc = gtphub_gtp_bind_init(&hub->to_ggsns[port_id], + &cfg->to_ggsns[port_id], + from_ggsns_read_cb, hub, port_id); + if (rc < 0) + return rc; + + rc = gtphub_gtp_bind_init(&hub->to_sgsns[port_id], + &cfg->to_sgsns[port_id], + from_sgsns_read_cb, hub, port_id); + if (rc < 0) + return rc; + + /* ... */ + } + return 0; +} + +struct gtphub_peer *gtphub_peer_new(struct gtphub_bind *bind) +{ + struct gtphub_peer *n = talloc_zero(osmo_gtphub_ctx, struct gtphub_peer); + llist_add(&n->entry, &bind->peers); + return n; +} + +void gtphub_peer_del(struct gtphub_peer *peer) +{ + llist_del(&peer->entry); + talloc_free(peer); } diff --git a/openbsc/src/gprs/gtphub_main.c b/openbsc/src/gprs/gtphub_main.c index f225efc..b43e28d 100644 --- a/openbsc/src/gprs/gtphub_main.c +++ b/openbsc/src/gprs/gtphub_main.c @@ -20,27 +20,17 @@ */ #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 <osmocom/core/utils.h> #include <openbsc/debug.h> - -#include <gtp.h> - -#include <unistd.h> +#include <openbsc/gtphub.h> #define LOGERR(fmt, args...) \ LOGP(DGTPHUB, LOGL_ERROR, fmt, ##args) @@ -113,7 +103,6 @@ int osmo_sockaddr_init(struct sockaddr_storage *addr, socklen_t *addr_len, } -void *tall_bsc_ctx; const char *gtphub_copyright = "Copyright (C) 2015 sysmocom s.m.f.c GmbH &lt;info(a)sysmocom.de&gt;\r\n&quot; @@ -142,139 +131,77 @@ static const struct log_info gtphub_log_info = { .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) +void log_cfg(struct gtphub_cfg *cfg) { - 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); + struct gtphub_cfg_addr *a; + a = &cfg->to_sgsns[GTPH_PORT_CONTROL].bind; + LOG("to-SGSNs bind, Control: %s port %d\n", + a->addr_str, a->port); + a = &cfg->to_sgsns[GTPH_PORT_USER].bind; + LOG("to-SGSNs bind, User: %s port %d\n", + a->addr_str, a->port); + a = &cfg->to_ggsns[GTPH_PORT_CONTROL].bind; + LOG("to-GGSNs bind, Control: %s port %d\n", + a->addr_str, a->port); + a = &cfg->to_ggsns[GTPH_PORT_USER].bind; + LOG("to-GGSNs bind, User: %s port %d\n", + a->addr_str, a->port); } int main(int argc, char **argv) { + osmo_gtphub_ctx = talloc_named_const(NULL, 0, "osmo_gtphub"); + 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; + struct gtphub_cfg _cfg = { + .to_sgsns = { + { .bind = { + .addr_str = "127.0.0.3", + .port = 2123, + } }, + { .bind = { + .addr_str = "127.0.0.3", + .port = 2152, + } }, + }, + .to_ggsns = { + { .bind = { + .addr_str = "127.0.0.4", + .port = 2123, + } }, + { .bind = { + .addr_str = "127.0.0.4", + .port = 2152, + } }, + }, + }; - memset(&clients_ofd, 0, sizeof(clients_ofd)); - clients_ofd.when = BSC_FD_READ; - clients_ofd.cb = clients_read_cb; - clients_ofd.data = &server_ofd; + struct gtphub_cfg *cfg = &_cfg; - 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); - } + struct gtphub _hub; + struct gtphub *hub = &_hub; - memset(&server_ofd, 0, sizeof(server_ofd)); - server_ofd.when = BSC_FD_READ; - server_ofd.cb = server_read_cb; - server_ofd.data = &clients_ofd; + if (gtphub_init(hub, cfg) != 0) + return -1; - 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); + /* TODO this will not be configured, gtphub will have to find the + * ggsns from incoming GTP PDUs. */ + /* Where the GTP ggsn sits that we're relaying for */ + const char* ggsn_addr_str = "127.0.0.2"; + uint16_t ggsn_port = 2123; + struct gtphub_peer *test_ggsn = gtphub_peer_new(&hub->to_ggsns[GTPH_PORT_CONTROL]); + rc = osmo_sockaddr_init(&test_ggsn->addr.a, &test_ggsn->addr.l, + AF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, + ggsn_addr_str, ggsn_port); + if (rc != 0) { + LOGERR("Cannot resolve '%s port %d'\n", ggsn_addr_str, ggsn_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); + log_cfg(cfg); int daemonize = 0; -- 2.1.4

Sponsored-by: On-Waves ehi diff --git a/openbsc/include/openbsc/gtphub.h b/openbsc/include/openbsc/gtphub.h index 7c89db1..7354786 100644 --- a/openbsc/include/openbsc/gtphub.h +++ b/openbsc/include/openbsc/gtphub.h @@ -38,6 +38,46 @@ enum gtphub_port_idx { extern const char* const gtphub_port_idx_names[GTPH_PORT_N]; +/* Generator for unused TEI IDs. So far this counts upwards from zero, but the + * implementation may change in the future. Treat this like an opaque struct. */ +struct tei_pool { + uint32_t last_tei; +}; + +void tei_pool_init(struct tei_pool *pool); + +/* Return the next unused TEI from the tei_pool. */ +uint32_t tei_pool_next(struct tei_pool *pool); + + +struct tei_mapping { + struct llist_head entry; + + uint32_t orig; + uint32_t repl; +}; + +struct tei_map { + struct tei_pool *pool; + struct llist_head mappings; +}; + +/* Initialize an (already allocated) tei_map, and set the map's TEI pool. + * Multiple tei_map instances may use the same tei_pool. */ +void tei_map_init(struct tei_map *map, struct tei_pool *pool); + +/* Return a replacement TEI for tei_orig. If tei_orig is unknown, create a new + * mapping using a so far unused TEI to map tei_orig to. Return 0 on error. */ +uint32_t tei_map_get(struct tei_map *map, uint32_t tei_orig); + +/* Return the original TEI for a replacement TEI. If no mapping exists to + * tei_repl, return 0. */ +uint32_t tei_map_get_rev(struct tei_map *map, uint32_t tei_repl); + +/* Remove the mapping for tei_orig, if it exists. */ +void tei_map_del(struct tei_map *map, uint32_t tei_orig); + + /* config */ struct gtphub_cfg_addr { @@ -66,10 +106,12 @@ struct gtphub_peer { struct llist_head entry; struct gtphub_addr addr; + struct tei_map teim; }; struct gtphub_bind { struct osmo_fd ofd; + struct tei_pool teip; /* list of struct gtphub_peer */ struct llist_head peers; diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index 577a2d0..a80243c 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -21,6 +21,7 @@ #include <string.h> #include <errno.h> +#include <inttypes.h> #include <netinet/in.h> #include <openbsc/gtphub.h> @@ -54,6 +55,82 @@ const char* const gtphub_port_idx_names[GTPH_PORT_N] = { }; +void tei_pool_init(struct tei_pool *pool) +{ + *pool = (struct tei_pool){}; +} + +uint32_t tei_pool_next(struct tei_pool *pool) +{ + pool->last_tei ++; + + OSMO_ASSERT(pool->last_tei > 0); + /* TODO: gracefully handle running out of TEIs. */ + /* TODO: random TEIs. */ + + return pool->last_tei; +} + +void tei_map_init(struct tei_map *map, struct tei_pool *pool) +{ + *map = (struct tei_map){}; + map->pool = pool; + INIT_LLIST_HEAD(&map->mappings); +} + +static uint32_t tei_map_new(struct tei_map *map, uint32_t tei_orig) +{ + struct tei_mapping *mapping; + mapping = talloc_zero(osmo_gtphub_ctx, struct tei_mapping); + OSMO_ASSERT(mapping); + mapping->orig = tei_orig; + mapping->repl = tei_pool_next(map->pool); + llist_add(&mapping->entry, &map->mappings); + return mapping->repl; +} + +uint32_t tei_map_get(struct tei_map *map, uint32_t tei_orig) +{ + OSMO_ASSERT(tei_orig != 0); + + struct tei_mapping *mapping; + llist_for_each_entry(mapping, &map->mappings, entry) { + if (mapping->orig == tei_orig) + return mapping->repl; + } + /* Not found. */ + + return tei_map_new(map, tei_orig); +} + +uint32_t tei_map_get_rev(struct tei_map *map, uint32_t tei_repl) +{ + OSMO_ASSERT(tei_repl != 0); + + struct tei_mapping *pos; + llist_for_each_entry(pos, &map->mappings, entry) { + if (pos->repl == tei_repl) { + OSMO_ASSERT(pos->orig); + return pos->orig; + } + } + return 0; +} + +void tei_map_del(struct tei_map *map, uint32_t tei_orig) +{ + struct tei_mapping *mapping; + llist_for_each_entry(mapping, &map->mappings, entry) { + if (mapping->orig == tei_orig) { + llist_del(&mapping->entry); + talloc_free(mapping); + return; + } + } + LOGERR("No mapping exists for TEI %" PRIu32 ".\n", tei_orig); +} + + /* gtphub */ void gtphub_zero(struct gtphub *hub) @@ -93,6 +170,7 @@ static int gtphub_gtp_bind_init(struct gtphub_bind *b, { memset(b, '\0', sizeof(*b)); + tei_pool_init(&b->teip); INIT_LLIST_HEAD(&b->peers); if (gtphub_sock_init(&b->ofd, &cfg->bind, cb, cb_data, ofd_id) != 0) @@ -240,6 +318,9 @@ int gtphub_init(struct gtphub *hub, struct gtphub_cfg *cfg) struct gtphub_peer *gtphub_peer_new(struct gtphub_bind *bind) { struct gtphub_peer *n = talloc_zero(osmo_gtphub_ctx, struct gtphub_peer); + + tei_map_init(&n->teim, &bind->teip); + llist_add(&n->entry, &bind->peers); return n; } -- 2.1.4

Sponsored-by: On-Waves ehi diff --git a/openbsc/tests/gtphub/Makefile.am b/openbsc/tests/gtphub/Makefile.am index 7cc3ac9..5347811 100644 --- a/openbsc/tests/gtphub/Makefile.am +++ b/openbsc/tests/gtphub/Makefile.am @@ -9,6 +9,7 @@ noinst_PROGRAMS = gtphub_test gtphub_test_SOURCES = gtphub_test.c gtphub_test_LDADD = \ + $(top_builddir)/src/gprs/gtphub.o \ $(LIBOSMOCORE_LIBS) \ -lgtp -lrt diff --git a/openbsc/tests/gtphub/gtphub_test.c b/openbsc/tests/gtphub/gtphub_test.c index 95f82c3..25e51e7 100644 --- a/openbsc/tests/gtphub/gtphub_test.c +++ b/openbsc/tests/gtphub/gtphub_test.c @@ -28,11 +28,65 @@ #include <openbsc/debug.h> +#include <openbsc/gtphub.h> + void *osmo_gtphub_ctx; -static void test_gtphub_api(void) +/* TODO copied from libosmo-abis/src/subchan_demux.c, remove dup */ +static int llist_len(struct llist_head *head) +{ + struct llist_head *entry; + int i = 0; + + llist_for_each(entry, head) + i++; + + return i; +} + +static void test_tei_map(void) { - OSMO_ASSERT(1); + /* Basic */ + struct tei_pool _pool; + struct tei_pool *pool = &_pool; + struct tei_map _map; + struct tei_map *map = &_map; + + tei_pool_init(pool); + tei_map_init(map, pool); + + OSMO_ASSERT(llist_empty(&map->mappings)); + +#define TEST_N 100 +#define TEST_I 123 + uint32_t i, check_i; + uint32_t m[TEST_N]; + + /* create TEST_N mappings */ + for (i = 0; i < TEST_N; i++) { + m[i] = tei_map_get(map, TEST_I + i); + OSMO_ASSERT(m[i] != 0); + OSMO_ASSERT(llist_len(&map->mappings) == (i+1)); + for (check_i = 0; check_i < i; check_i++) + OSMO_ASSERT(m[check_i] != m[i]); + } + OSMO_ASSERT(llist_len(&map->mappings) == TEST_N); + + /* verify mappings */ + for (i = 0; i < TEST_N; i++) { + OSMO_ASSERT(tei_map_get(map, TEST_I + i) == m[i]); + OSMO_ASSERT(tei_map_get_rev(map, m[i]) == (TEST_I + i)); + } + OSMO_ASSERT(llist_len(&map->mappings) == TEST_N); + + /* remove all mappings */ + for (i = 0; i < TEST_N; i++) { + tei_map_del(map, TEST_I + i); + OSMO_ASSERT(llist_len(&map->mappings) == (TEST_N - (i+1))); + } + OSMO_ASSERT(llist_empty(&map->mappings)); +#undef TEST_N +#undef TEST_I } static struct log_info_cat gtphub_categories[] = { @@ -54,7 +108,7 @@ int main(int argc, char **argv) osmo_init_logging(&info); osmo_gtphub_ctx = talloc_named_const(NULL, 0, "osmo_gtphub"); - test_gtphub_api(); + test_tei_map(); printf("Done\n"); talloc_report_full(osmo_gtphub_ctx, stderr); -- 2.1.4

diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index 208b623..1d9c6d5 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -41,6 +41,8 @@ void *osmo_gtphub_ctx; #define LOG(fmt, args...) \ LOGP(DGTPHUB, LOGL_NOTICE, fmt, ##args) +#define ZERO_STRUCT(struct_pointer) memset(struct_pointer, '\0', sizeof(*(struct_pointer))) + /* TODO move this to osmocom/core/select.h ? */ typedef int (*osmo_fd_cb_t)(struct osmo_fd *fd, unsigned int what); @@ -182,7 +184,7 @@ void validate_gtp_header(struct gtp_packet_desc *p) * 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)); + ZERO_STRUCT(res); res->data = (union gtp_packet*)data; res->data_len = data_len; @@ -221,7 +223,7 @@ uint32_t tei_pool_next(struct tei_pool *pool) void tei_map_init(struct tei_map *map, struct tei_pool *pool) { - *map = (struct tei_map){}; + ZERO_STRUCT(map); map->pool = pool; INIT_LLIST_HEAD(&map->mappings); } @@ -283,7 +285,7 @@ void tei_map_del(struct tei_map *map, uint32_t tei_orig) void gtphub_zero(struct gtphub *hub) { - memset(hub, '\0', sizeof(*hub)); + ZERO_STRUCT(hub); } static int gtphub_sock_init(struct osmo_fd *ofd, @@ -316,7 +318,7 @@ static int gtphub_gtp_bind_init(struct gtphub_bind *b, osmo_fd_cb_t cb, void *cb_data, unsigned int ofd_id) { - memset(b, '\0', sizeof(*b)); + ZERO_STRUCT(b); tei_pool_init(&b->teip); INIT_LLIST_HEAD(&b->peers); -- 2.1.4

diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index e849a8f..73e7c02 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -23,6 +23,7 @@ #include <errno.h> #include <inttypes.h> #include <netinet/in.h> +#include <arpa/inet.h> #include <gtp.h> @@ -33,6 +34,8 @@ #include <osmocom/core/logging.h> #include <osmocom/core/socket.h> +#define GTPHUB_DEBUG 1 + void *osmo_gtphub_ctx; #define LOGERR(fmt, args...) \ @@ -54,6 +57,23 @@ typedef int (*osmo_fd_cb_t)(struct osmo_fd *fd, unsigned int what); #define ntoh16(x) ntohs(x) #define ntoh32(x) ntohl(x) +/* cheat to use gtpie.h API. + * TODO publish gtpie.h upon openggsn installation */ +union gtpie_member; +extern int gtpie_decaps(union gtpie_member *ie[], int version, + void *pack, unsigned len); +extern int gtpie_gettv0(union gtpie_member *ie[], int type, int instance, + void *dst, unsigned int size); +extern int gtpie_gettv1(union gtpie_member *ie[], int type, int instance, + uint8_t *dst); +extern int gtpie_gettlv(union gtpie_member *ie[], int type, int instance, + unsigned int *length, void *dst, unsigned int size); +#define GTPIE_IMSI 2 /* International Mobile Subscriber Identity 8 */ +#define GTPIE_NSAPI 20 /* NSAPI 1 */ +#define GTPIE_GSN_ADDR 133 /* GSN Address */ +#define GTPIE_SIZE 256 +/* end of things needed from gtpie.h */ + /* TODO move GTP header stuff to openggsn/gtp/ ? See gtp_decaps*() */ enum gtp_rc { @@ -72,6 +92,7 @@ struct gtp_packet_desc { int header_len; int version; int rc; + union gtpie_member *ie[GTPIE_SIZE]; }; /* Validate GTP version 0 data; analogous to validate_gtp1_header(), see there. @@ -194,6 +215,45 @@ void validate_gtp_header(struct gtp_packet_desc *p) } } + +/* Return the value of the i'th IMSI IEI by copying to *imsi. + * The first IEI is reached by passing i = 0. + * imsi must point at allocated space of (at least) 8 bytes. + * Return 1 on success, or 0 if not found. */ +static int get_ie_imsi(union gtpie_member *ie[], uint8_t *imsi, int i) +{ + return gtpie_gettv0(ie, GTPIE_IMSI, i, imsi, 8) == 0; +} + +/* Analogous to get_ie_imsi(). nsapi must point at a single uint8_t. */ +static int get_ie_nsapi(union gtpie_member *ie[], uint8_t *nsapi, int i) +{ + return gtpie_gettv1(ie, GTPIE_NSAPI, i, nsapi) == 0; +} + +static char imsi_digit_to_char(uint8_t nibble) +{ + nibble &= 0x0f; + if (nibble > 9) + return (nibble == 0x0f) ? '\0' : '?'; + return '0' + nibble; +} + +/* Return a human readable IMSI string, in a static buffer. + * imsi must point at 8 octets of IMSI IE encoded IMSI data. */ +static const char *imsi_to_str(uint8_t *imsi) +{ + static char str[17]; + int i; + + for (i = 0; i < 8; i++) { + str[2*i] = imsi_digit_to_char(imsi[i]); + str[2*i + 1] = imsi_digit_to_char(imsi[i] >> 4); + } + str[16] = '\0'; + return str; +} + /* 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). */ @@ -207,6 +267,43 @@ static void gtp_decode(const uint8_t *data, int data_len, struct gtp_packet_desc if (res->rc == GTP_RC_TINY) LOG("tiny: no IEs in this GTP packet\n"); + + if (res->rc != GTP_RC_PDU) + return; + + if (gtpie_decaps(res->ie, res->version, + (void*)(data + res->header_len), + res->data_len - res->header_len) != 0) { + res->rc = GTP_RC_INVALID_IE; + return; + } + +#if GTPHUB_DEBUG + int i; + + for (i = 0; i < 10; i++) { + uint8_t imsi[8]; + if (!get_ie_imsi(res->ie, imsi, i)) + break; + LOG("- IMSI %s\n", imsi_to_str(imsi)); + } + + for (i = 0; i < 10; i++) { + uint8_t nsapi; + if (!get_ie_nsapi(res->ie, &nsapi, i)) + break; + LOG("- NSAPI %d\n", (int)nsapi); + } + + for (i = 0; i < 10; i++) { + unsigned int addr_len; + struct in_addr addr; + if (gtpie_gettlv(res->ie, GTPIE_GSN_ADDR, i, &addr_len, &addr, + sizeof(addr)) != 0) + break; + LOG("- addr %s\n", inet_ntoa(addr)); + } +#endif } -- 2.1.4

Avoid sequence number collisions and allow routing a GGSN's response back to the SGSN that sent a request: - Towards each GGSN, send other sequence numbers than received from an SGSN, - and remember the mapping (with timeouts). - When receiving from a GGSN, find the SGSN from the sequence number returned. This covers only requests by the SGSN followed by GGSN responses, it does not cover requests initiated by a GGSN. Sponsored-by: On-Waves ehi diff --git a/openbsc/include/openbsc/gtphub.h b/openbsc/include/openbsc/gtphub.h index 7354786..ccea5aa 100644 --- a/openbsc/include/openbsc/gtphub.h +++ b/openbsc/include/openbsc/gtphub.h @@ -23,6 +23,7 @@ #include <stdint.h> #include <sys/socket.h> +#include <sys/time.h> #include <osmocom/core/select.h> @@ -107,6 +108,18 @@ struct gtphub_peer { struct gtphub_addr addr; struct tei_map teim; + uint16_t next_peer_seq; /* the latest used sequence nr + 1 */ + struct llist_head seq_map; /* of struct gtphub_seq_mapping */ + int ref_count; /* references from other peers' seq_maps */ +}; + +struct gtphub_seq_mapping { + struct llist_head entry; + + uint16_t peer_seq; + struct gtphub_peer *from; + uint16_t from_seq; + struct timeval timeout; }; struct gtphub_bind { diff --git a/openbsc/src/gprs/gtphub.c b/openbsc/src/gprs/gtphub.c index 9f3e021..f6733e3 100644 --- a/openbsc/src/gprs/gtphub.c +++ b/openbsc/src/gprs/gtphub.c @@ -22,6 +22,7 @@ #include <string.h> #include <errno.h> #include <inttypes.h> +#include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h> @@ -35,6 +36,7 @@ #include <osmocom/core/socket.h> #define GTPHUB_DEBUG 1 +#define MAP_SEQ 1 void *osmo_gtphub_ctx; @@ -57,6 +59,8 @@ typedef int (*osmo_fd_cb_t)(struct osmo_fd *fd, unsigned int what); #define ntoh16(x) ntohs(x) #define ntoh32(x) ntohl(x) +#define hton16(x) htons(x) + /* cheat to use gtpie.h API. * TODO publish gtpie.h upon openggsn installation */ union gtpie_member; @@ -87,7 +91,7 @@ enum gtp_rc { }; struct gtp_packet_desc { - const union gtp_packet *data; + union gtp_packet *data; int data_len; int header_len; int version; @@ -481,6 +485,63 @@ static int gtphub_read(struct osmo_fd *from, return received; } +#if MAP_SEQ + +inline uint16_t get_seq(struct gtp_packet_desc *p) +{ + OSMO_ASSERT(p->version == 1); + return ntoh16(p->data->gtp1l.h.seq); +} + +inline void set_seq(struct gtp_packet_desc *p, uint16_t seq) +{ + OSMO_ASSERT(p->version == 1); + p->data->gtp1l.h.seq = hton16(seq); +} + +static int gtphub_map_seq(struct gtp_packet_desc *p, + struct gtphub_peer *from_peer, struct gtphub_peer *to_peer) +{ + + struct gtphub_seq_mapping *m = talloc_zero(osmo_gtphub_ctx, struct gtphub_seq_mapping); + OSMO_ASSERT(m); + + m->peer_seq = to_peer->next_peer_seq++; + m->from = from_peer; + m->from_seq = get_seq(p); + LOG(" MAP %d --> %d\n", (int)m->from_seq, (int)m->peer_seq); + + llist_add(&m->entry, &to_peer->seq_map); + set_seq(p, m->peer_seq); + + return 0; +} + +static struct gtphub_peer *gtphub_unmap_seq(struct gtp_packet_desc *p, + struct gtphub_peer *from_peer) +{ + OSMO_ASSERT(p->version == 1); + + uint16_t from_seq = get_seq(p); + + struct gtphub_seq_mapping *mapping; + llist_for_each_entry(mapping, &from_peer->seq_map, entry) { + if (mapping->peer_seq == from_seq) + break; + } + + if (&mapping->entry == &from_peer->seq_map) { + /* not found. */ + return NULL; + } + + LOG("UNMAP %d <-- %d\n", (int)(mapping->from_seq), (int)from_seq); + set_seq(p, mapping->from_seq); + return mapping->from; +} + +#endif + static int gtphub_write(struct osmo_fd *to, struct sockaddr_storage *to_addr, socklen_t to_addr_len, @@ -517,11 +578,14 @@ int from_ggsns_read_cb(struct osmo_fd *from_ggsns_ofd, unsigned int what) struct gtphub *hub = from_ggsns_ofd->data; + struct gtphub_peer *ggsn = NULL; + struct gtphub_peer *sgsn = NULL; + /* TODO this will not be hardcoded. */ - struct gtphub_peer *sgsn = llist_first(&hub->to_sgsns[port_idx].peers, - struct gtphub_peer, entry); - if (!sgsn) { - LOGERR("no sgsn"); + ggsn = llist_first(&hub->to_ggsns[port_idx].peers, + struct gtphub_peer, entry); + if (!ggsn) { + LOGERR("no ggsn\n"); return 0; } @@ -539,6 +603,20 @@ int from_ggsns_read_cb(struct osmo_fd *from_ggsns_ofd, unsigned int what) return 0; #endif +#if MAP_SEQ + sgsn = gtphub_unmap_seq(&p, ggsn); +#else + /* TODO this will not be hardcoded. */ + sgsn = llist_first(&hub->to_sgsns[port_idx].peers, + struct gtphub_peer, entry); +#endif + + if (!sgsn) { + LOGERR("no sgsn"); + return 0; + } + + return gtphub_write(&hub->to_sgsns[port_idx].ofd, &sgsn->addr.a, sgsn->addr.l, (uint8_t*)p.data, p.data_len); @@ -583,6 +661,10 @@ int from_sgsns_read_cb(struct osmo_fd *from_sgsns_ofd, unsigned int what) return 0; #endif +#if MAP_SEQ + gtphub_map_seq(&p, sgsn, ggsn); +#endif + return gtphub_write(&hub->to_ggsns[port_idx].ofd, &ggsn->addr.a, ggsn->addr.l, (uint8_t*)p.data, p.data_len); @@ -616,7 +698,9 @@ struct gtphub_peer *gtphub_peer_new(struct gtphub_bind *bind) { struct gtphub_peer *n = talloc_zero(osmo_gtphub_ctx, struct gtphub_peer); + INIT_LLIST_HEAD(&n->seq_map); tei_map_init(&n->teim, &bind->teip); + n->next_peer_seq = rand(); /* TODO seed or use something else */ llist_add(&n->entry, &bind->peers); return n; -- 2.1.4