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-rw-r--r--src/gtphub/gtphub.c2960
1 files changed, 2960 insertions, 0 deletions
diff --git a/src/gtphub/gtphub.c b/src/gtphub/gtphub.c
new file mode 100644
index 00000000..ca5857b3
--- /dev/null
+++ b/src/gtphub/gtphub.c
@@ -0,0 +1,2960 @@
+/* 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 <errno.h>
+#include <inttypes.h>
+#include <time.h>
+#include <limits.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <gtp.h>
+#include <gtpie.h>
+
+#include <osmocom/sgsn/gtphub.h>
+#include <osmocom/sgsn/debug.h>
+#include <osmocom/sgsn/gprs_utils.h>
+
+#include <osmocom/core/utils.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/socket.h>
+#include <osmocom/core/rate_ctr.h>
+#include <osmocom/core/stats.h>
+
+#include <osmocom/gsm/apn.h>
+
+
+static const int GTPH_GC_TICK_SECONDS = 1;
+
+void *osmo_gtphub_ctx;
+
+/* Convenience makro, note: only within this C file. */
+#define LOG(level, fmt, args...) \
+ LOGP(DGTPHUB, level, 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);
+
+/* 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)
+
+#define __llist_last(head) (((head)->next == (head)) ? NULL : (head)->prev)
+#define llist_last(head, type, entry) \
+ llist_entry(__llist_last(head), type, entry)
+
+/* 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_C = 2, /* a real packet with IEs */
+ GTP_RC_PDU_U = 3, /* a real packet with User data */
+
+ GTP_RC_TOOSHORT = -1,
+ GTP_RC_UNSUPPORTED_VERSION = -2,
+ GTP_RC_INVALID_IE = -3,
+};
+
+struct gtp_packet_desc {
+ union gtp_packet *data;
+ int data_len;
+ int header_len;
+ int version;
+ uint8_t type;
+ uint16_t seq;
+ uint32_t header_tei_rx;
+ uint32_t header_tei;
+ int rc; /* enum gtp_rc */
+ unsigned int plane_idx;
+ unsigned int side_idx;
+ struct gtphub_tunnel *tun;
+ time_t timestamp;
+ union gtpie_member *ie[GTPIE_SIZE];
+};
+
+struct pending_delete {
+ struct llist_head entry;
+ struct expiring_item expiry_entry;
+
+ struct gtphub_tunnel *tun;
+ uint8_t teardown_ind;
+ uint8_t nsapi;
+};
+
+
+/* counters */
+
+enum gtphub_counters_io {
+ GTPH_CTR_PKTS_IN = 0,
+ GTPH_CTR_PKTS_OUT,
+ GTPH_CTR_BYTES_IN,
+ GTPH_CTR_BYTES_OUT
+};
+
+static const struct rate_ctr_desc gtphub_counters_io_desc[] = {
+ { "packets.in", "Packets ( In)" },
+ { "packets.out", "Packets (Out)" },
+ { "bytes.in", "Bytes ( In)" },
+ { "bytes.out", "Bytes (Out)" },
+};
+
+static const struct rate_ctr_group_desc gtphub_ctrg_io_desc = {
+ .group_name_prefix = "gtphub:bind",
+ .group_description = "I/O Statistics",
+ .num_ctr = ARRAY_SIZE(gtphub_counters_io_desc),
+ .ctr_desc = gtphub_counters_io_desc,
+ .class_id = OSMO_STATS_CLASS_GLOBAL,
+};
+
+
+/* support */
+
+static const char *gtp_type_str(uint8_t type)
+{
+ switch (type) {
+ case 1:
+ return " (Echo Request)";
+ case 2:
+ return " (Echo Response)";
+ case 16:
+ return " (Create PDP Ctx Request)";
+ case 17:
+ return " (Create PDP Ctx Response)";
+ case 18:
+ return " (Update PDP Ctx Request)";
+ case 19:
+ return " (Update PDP Ctx Response)";
+ case 20:
+ return " (Delete PDP Ctx Request)";
+ case 21:
+ return " (Delete PDP Ctx Response)";
+ case 255:
+ return " (User Data)";
+ default:
+ return "";
+ }
+}
+
+void gsn_addr_copy(struct gsn_addr *gsna, const struct gsn_addr *src)
+{
+ *gsna = *src;
+}
+
+int gsn_addr_from_sockaddr(struct gsn_addr *gsna, uint16_t *port,
+ const struct osmo_sockaddr *sa)
+{
+ char addr_str[256];
+ char port_str[6];
+
+ if (osmo_sockaddr_to_strs(addr_str, sizeof(addr_str),
+ port_str, sizeof(port_str),
+ sa, (NI_NUMERICHOST | NI_NUMERICSERV))
+ != 0) {
+ return -1;
+ }
+
+ if (port)
+ *port = atoi(port_str);
+
+ return gsn_addr_from_str(gsna, addr_str);
+}
+
+int gsn_addr_from_str(struct gsn_addr *gsna, const char *numeric_addr_str)
+{
+ if ((!gsna) || (!numeric_addr_str))
+ return -1;
+
+ int af = AF_INET;
+ gsna->len = 4;
+ const char *pos = numeric_addr_str;
+ for (; *pos; pos++) {
+ if (*pos == ':') {
+ af = AF_INET6;
+ gsna->len = 16;
+ break;
+ }
+ }
+
+ int rc = inet_pton(af, numeric_addr_str, gsna->buf);
+ if (rc != 1) {
+ LOG(LOGL_ERROR, "Cannot resolve numeric address: '%s'\n",
+ numeric_addr_str);
+ return -1;
+ }
+ return 0;
+}
+
+const char *gsn_addr_to_str(const struct gsn_addr *gsna)
+{
+ static char buf[INET6_ADDRSTRLEN + 1];
+ return gsn_addr_to_strb(gsna, buf, sizeof(buf));
+}
+
+const char *gsn_addr_to_strb(const struct gsn_addr *gsna,
+ char *strbuf,
+ int strbuf_len)
+{
+ int af;
+ switch (gsna->len) {
+ case 4:
+ af = AF_INET;
+ break;
+ case 16:
+ af = AF_INET6;
+ break;
+ default:
+ return NULL;
+ }
+
+ const char *r = inet_ntop(af, gsna->buf, strbuf, strbuf_len);
+ if (!r) {
+ LOG(LOGL_ERROR, "Cannot convert gsn_addr to string:"
+ " %s: len=%d, buf=%s\n",
+ strerror(errno),
+ (int)gsna->len,
+ osmo_hexdump(gsna->buf, sizeof(gsna->buf)));
+ }
+ return r;
+}
+
+int gsn_addr_same(const struct gsn_addr *a, const struct gsn_addr *b)
+{
+ if (a == b)
+ return 1;
+ if ((!a) || (!b))
+ return 0;
+ if (a->len != b->len)
+ return 0;
+ return (memcmp(a->buf, b->buf, a->len) == 0)? 1 : 0;
+}
+
+static int gsn_addr_get(struct gsn_addr *gsna, const struct gtp_packet_desc *p,
+ int idx)
+{
+ if (p->rc != GTP_RC_PDU_C)
+ return -1;
+
+ unsigned int len;
+ /* gtpie.h fails to declare gtpie_gettlv()'s first arg as const. */
+ if (gtpie_gettlv((union gtpie_member**)p->ie, GTPIE_GSN_ADDR, idx,
+ &len, gsna->buf, sizeof(gsna->buf))
+ != 0)
+ return -1;
+ gsna->len = len;
+ return 0;
+}
+
+static int gsn_addr_put(const struct gsn_addr *gsna, struct gtp_packet_desc *p,
+ int idx)
+{
+ if (p->rc != GTP_RC_PDU_C)
+ return -1;
+
+ int ie_idx;
+ ie_idx = gtpie_getie(p->ie, GTPIE_GSN_ADDR, idx);
+
+ if (ie_idx < 0)
+ return -1;
+
+ struct gtpie_tlv *ie = &p->ie[ie_idx]->tlv;
+ int ie_l = ntoh16(ie->l);
+ if (ie_l != gsna->len) {
+ LOG(LOGL_ERROR, "Not implemented:"
+ " replace an IE address of different size:"
+ " replace %d with %d\n", (int)ie_l, (int)gsna->len);
+ return -1;
+ }
+
+ memcpy(ie->v, gsna->buf, (int)ie_l);
+ return 0;
+}
+
+/* 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) {
+ LOG(LOGL_ERROR, "GTP0 packet too short: %d\n", p->data_len);
+ p->rc = GTP_RC_TOOSHORT;
+ return;
+ }
+
+ p->type = ntoh8(pheader->type);
+ p->seq = ntoh16(pheader->seq);
+ p->header_tei_rx = 0; /* TODO */
+ p->header_tei = p->header_tei_rx;
+
+ 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)) {
+ LOG(LOGL_ERROR, "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;
+ }
+
+ LOG(LOGL_DEBUG, "GTP v0 TID = %" PRIu64 "\n", pheader->tid);
+ p->header_len = GTP0_HEADER_SIZE;
+ p->rc = GTP_RC_PDU_C;
+}
+
+/* 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)){
+ LOG(LOGL_ERROR, "GTP packet too short: %d\n", p->data_len);
+ p->rc = GTP_RC_TOOSHORT;
+ return;
+ }
+
+ p->type = ntoh8(pheader->type);
+ p->header_tei_rx = ntoh32(pheader->tei);
+ p->header_tei = p->header_tei_rx;
+ p->seq = ntoh16(pheader->seq);
+
+ LOG(LOGL_DEBUG, "| GTPv1\n");
+ LOG(LOGL_DEBUG, "| type = %" PRIu8 " 0x%02" PRIx8 "\n", p->type, p->type);
+ LOG(LOGL_DEBUG, "| length = %" PRIu16 " 0x%04" PRIx16 "\n", ntoh16(pheader->length), ntoh16(pheader->length));
+ LOG(LOGL_DEBUG, "| TEI = %" PRIu32 " 0x%08" PRIx32 "\n", p->header_tei_rx, p->header_tei_rx);
+ LOG(LOGL_DEBUG, "| seq = %" PRIu16 " 0x%04" PRIx16 "\n", p->seq, p->seq);
+ LOG(LOGL_DEBUG, "| npdu = %" PRIu8 " 0x%02" PRIx8 "\n", pheader->npdu, pheader->npdu);
+ LOG(LOGL_DEBUG, "| 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;
+ return;
+ }
+
+ /* Check packet length field versus length of packet */
+ int announced_len = ntoh16(pheader->length) + GTP1_HEADER_SIZE_SHORT;
+ if (p->data_len != announced_len) {
+ LOG(LOGL_ERROR, "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_C;
+ 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) {
+ LOG(LOGL_ERROR, "Discarding packet - too small: %d\n",
+ p->data_len);
+ 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:
+ LOG(LOGL_ERROR, "Unsupported GTP version: %d\n", p->version);
+ p->rc = GTP_RC_UNSUPPORTED_VERSION;
+ break;
+ }
+}
+
+
+/* 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[], int i, uint8_t *imsi)
+{
+ 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[], int i, uint8_t *nsapi)
+{
+ 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 int imsi_to_str(uint8_t *imsi, const char **imsi_str)
+{
+ static char str[17];
+ int i;
+
+ for (i = 0; i < 8; i++) {
+ char c;
+ c = imsi_digit_to_char(imsi[i]);
+ if (c == '?')
+ return -1;
+ str[2*i] = c;
+
+ c = imsi_digit_to_char(imsi[i] >> 4);
+ if (c == '?')
+ return -1;
+ str[2*i + 1] = c;
+ }
+ str[16] = '\0';
+ *imsi_str = str;
+ return 1;
+}
+
+/* Return 0 if not present, 1 if present and decoded successfully, -1 if
+ * present but cannot be decoded. */
+static int get_ie_imsi_str(union gtpie_member *ie[], int i,
+ const char **imsi_str)
+{
+ uint8_t imsi_buf[8];
+ if (!get_ie_imsi(ie, i, imsi_buf))
+ return 0;
+ return imsi_to_str(imsi_buf, imsi_str);
+}
+
+/* Return 0 if not present, 1 if present and decoded successfully, -1 if
+ * present but cannot be decoded. */
+static int get_ie_apn_str(union gtpie_member *ie[], const char **apn_str)
+{
+ static char apn_buf[GSM_APN_LENGTH];
+ unsigned int len;
+ if (gtpie_gettlv(ie, GTPIE_APN, 0,
+ &len, apn_buf, sizeof(apn_buf)) != 0)
+ return 0;
+
+ if (len < 2) {
+ LOG(LOGL_ERROR, "APN IE: invalid length: %d\n",
+ (int)len);
+ return -1;
+ }
+
+ if (len > (sizeof(apn_buf) - 1))
+ len = sizeof(apn_buf) - 1;
+ apn_buf[len] = '\0';
+
+ *apn_str = osmo_apn_to_str(apn_buf, (uint8_t*)apn_buf, len);
+ if (!(*apn_str)) {
+ LOG(LOGL_ERROR, "APN IE: present but cannot be decoded: %s\n",
+ osmo_hexdump((uint8_t*)apn_buf, len));
+ return -1;
+ }
+ return 1;
+}
+
+
+/* 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,
+ unsigned int from_side_idx,
+ unsigned int from_plane_idx,
+ struct gtp_packet_desc *res,
+ time_t now)
+{
+ ZERO_STRUCT(res);
+ res->data = (union gtp_packet*)data;
+ res->data_len = data_len;
+ res->side_idx = from_side_idx;
+ res->plane_idx = from_plane_idx;
+ res->timestamp = now;
+
+ validate_gtp_header(res);
+
+ if (res->rc <= 0)
+ return;
+
+ LOG(LOGL_DEBUG, "Valid GTP header (v%d)\n", res->version);
+
+ if (from_plane_idx == GTPH_PLANE_USER) {
+ res->rc = GTP_RC_PDU_U;
+ return;
+ }
+
+ if (res->rc != GTP_RC_PDU_C) {
+ LOG(LOGL_DEBUG, "no IEs in this GTP packet\n");
+ 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;
+ LOG(LOGL_ERROR, "INVALID: cannot decode IEs."
+ " Dropping GTP packet%s.\n",
+ gtp_type_str(res->type)
+ );
+ return;
+ }
+
+#if 1
+ /* TODO if (<loglevel is debug>)
+ (waiting for a commit from jerlbeck) */
+ int i;
+
+ for (i = 0; i < 10; i++) {
+ const char *imsi;
+ if (get_ie_imsi_str(res->ie, i, &imsi) < 1)
+ break;
+ LOG(LOGL_DEBUG, "| IMSI %s\n", imsi);
+ }
+
+ for (i = 0; i < 10; i++) {
+ uint8_t nsapi;
+ if (!get_ie_nsapi(res->ie, i, &nsapi))
+ break;
+ LOG(LOGL_DEBUG, "| NSAPI %d\n", (int)nsapi);
+ }
+
+ for (i = 0; i < 2; i++) {
+ struct gsn_addr addr;
+ if (gsn_addr_get(&addr, res, i) == 0)
+ LOG(LOGL_DEBUG, "| addr %s\n", gsn_addr_to_str(&addr));
+ }
+
+ for (i = 0; i < 10; i++) {
+ uint32_t tei;
+ if (gtpie_gettv4(res->ie, GTPIE_TEI_DI, i, &tei) != 0)
+ break;
+ LOG(LOGL_DEBUG, "| TEI DI (USER) %" PRIu32 " 0x%08" PRIx32 "\n",
+ tei, tei);
+ }
+
+ for (i = 0; i < 10; i++) {
+ uint32_t tei;
+ if (gtpie_gettv4(res->ie, GTPIE_TEI_C, i, &tei) != 0)
+ break;
+ LOG(LOGL_DEBUG, "| TEI (CTRL) %" PRIu32 " 0x%08" PRIx32 "\n",
+ tei, tei);
+ }
+#endif
+}
+
+
+/* expiry */
+
+void expiry_init(struct expiry *exq, int expiry_in_seconds)
+{
+ ZERO_STRUCT(exq);
+ exq->expiry_in_seconds = expiry_in_seconds;
+ INIT_LLIST_HEAD(&exq->items);
+}
+
+void expiry_add(struct expiry *exq, struct expiring_item *item, time_t now)
+{
+ item->expiry = now + exq->expiry_in_seconds;
+
+ OSMO_ASSERT(llist_empty(&exq->items)
+ || (item->expiry
+ >= llist_last(&exq->items, struct expiring_item, entry)->expiry));
+
+ /* Add/move to the tail to always sort by expiry, ascending. */
+ llist_del(&item->entry);
+ llist_add_tail(&item->entry, &exq->items);
+}
+
+int expiry_tick(struct expiry *exq, time_t now)
+{
+ int expired = 0;
+ struct expiring_item *m, *n;
+ llist_for_each_entry_safe(m, n, &exq->items, entry) {
+ if (m->expiry <= now) {
+ expiring_item_del(m);
+ expired ++;
+ } else {
+ /* The items are added sorted by expiry. So when we hit
+ * an unexpired entry, only more unexpired ones will
+ * follow. */
+ break;
+ }
+ }
+ return expired;
+}
+
+void expiry_clear(struct expiry *exq)
+{
+ struct expiring_item *m, *n;
+ llist_for_each_entry_safe(m, n, &exq->items, entry) {
+ expiring_item_del(m);
+ }
+}
+
+void expiring_item_init(struct expiring_item *item)
+{
+ ZERO_STRUCT(item);
+ INIT_LLIST_HEAD(&item->entry);
+}
+
+void expiring_item_del(struct expiring_item *item)
+{
+ OSMO_ASSERT(item);
+ llist_del(&item->entry);
+ INIT_LLIST_HEAD(&item->entry);
+ if (item->del_cb) {
+ /* avoid loops */
+ del_cb_t del_cb = item->del_cb;
+ item->del_cb = 0;
+ (del_cb)(item);
+ }
+}
+
+
+/* nr_map, nr_pool */
+
+void nr_pool_init(struct nr_pool *pool, nr_t nr_min, nr_t nr_max)
+{
+ *pool = (struct nr_pool){
+ .nr_min = nr_min,
+ .nr_max = nr_max,
+ .last_nr = nr_max
+ };
+}
+
+nr_t nr_pool_next(struct nr_pool *pool)
+{
+ if (pool->last_nr >= pool->nr_max)
+ pool->last_nr = pool->nr_min;
+ else
+ pool->last_nr ++;
+
+ return pool->last_nr;
+}
+
+void nr_map_init(struct nr_map *map, struct nr_pool *pool,
+ struct expiry *exq)
+{
+ ZERO_STRUCT(map);
+ map->pool = pool;
+ map->add_items_to_expiry = exq;
+ INIT_LLIST_HEAD(&map->mappings);
+}
+
+void nr_mapping_init(struct nr_mapping *m)
+{
+ ZERO_STRUCT(m);
+ INIT_LLIST_HEAD(&m->entry);
+ expiring_item_init(&m->expiry_entry);
+}
+
+void nr_map_add(struct nr_map *map, struct nr_mapping *mapping, time_t now)
+{
+ /* Generate a mapped number */
+ mapping->repl = nr_pool_next(map->pool);
+
+ /* Add to the tail to always yield a list sorted by expiry, in
+ * ascending order. */
+ llist_add_tail(&mapping->entry, &map->mappings);
+ nr_map_refresh(map, mapping, now);
+}
+
+void nr_map_refresh(struct nr_map *map, struct nr_mapping *mapping, time_t now)
+{
+ if (!map->add_items_to_expiry)
+ return;
+ expiry_add(map->add_items_to_expiry,
+ &mapping->expiry_entry,
+ now);
+}
+
+void nr_map_clear(struct nr_map *map)
+{
+ struct nr_mapping *m;
+ struct nr_mapping *n;
+ llist_for_each_entry_safe(m, n, &map->mappings, entry) {
+ nr_mapping_del(m);
+ }
+}
+
+int nr_map_empty(const struct nr_map *map)
+{
+ return llist_empty(&map->mappings);
+}
+
+struct nr_mapping *nr_map_get(const struct nr_map *map,
+ void *origin, nr_t nr_orig)
+{
+ struct nr_mapping *mapping;
+ llist_for_each_entry(mapping, &map->mappings, entry) {
+ if ((mapping->origin == origin)
+ && (mapping->orig == nr_orig))
+ return mapping;
+ }
+ /* Not found. */
+ return NULL;
+}
+
+struct nr_mapping *nr_map_get_inv(const struct nr_map *map, nr_t nr_repl)
+{
+ struct nr_mapping *mapping;
+ llist_for_each_entry(mapping, &map->mappings, entry) {
+ if (mapping->repl == nr_repl) {
+ return mapping;
+ }
+ }
+ /* Not found. */
+ return NULL;
+}
+
+void nr_mapping_del(struct nr_mapping *mapping)
+{
+ OSMO_ASSERT(mapping);
+ llist_del(&mapping->entry);
+ INIT_LLIST_HEAD(&mapping->entry);
+ expiring_item_del(&mapping->expiry_entry);
+}
+
+
+/* gtphub */
+
+const char* const gtphub_plane_idx_names[GTPH_PLANE_N] = {
+ "CTRL",
+ "USER",
+};
+
+const uint16_t gtphub_plane_idx_default_port[GTPH_PLANE_N] = {
+ 2123,
+ 2152,
+};
+
+const char* const gtphub_side_idx_names[GTPH_SIDE_N] = {
+ "SGSN",
+ "GGSN",
+};
+
+time_t gtphub_now(void)
+{
+ struct timespec now_tp;
+ OSMO_ASSERT(osmo_clock_gettime(CLOCK_MONOTONIC, &now_tp) >= 0);
+ return now_tp.tv_sec;
+}
+
+/* Remove a gtphub_peer from its list and free it. */
+static void gtphub_peer_del(struct gtphub_peer *peer)
+{
+ OSMO_ASSERT(llist_empty(&peer->addresses));
+ nr_map_clear(&peer->seq_map);
+ llist_del(&peer->entry);
+ talloc_free(peer);
+}
+
+static void gtphub_peer_addr_del(struct gtphub_peer_addr *pa)
+{
+ OSMO_ASSERT(llist_empty(&pa->ports));
+ llist_del(&pa->entry);
+ talloc_free(pa);
+}
+
+static void gtphub_peer_port_del(struct gtphub_peer_port *pp)
+{
+ OSMO_ASSERT(pp->ref_count == 0);
+ llist_del(&pp->entry);
+ rate_ctr_group_free(pp->counters_io);
+ talloc_free(pp);
+}
+
+/* From the information in the gtp_packet_desc, return the address of a GGSN.
+ * Return -1 on error. */
+static int gtphub_resolve_ggsn(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port **pp);
+
+/* See gtphub_ext.c (wrapped by unit test) */
+struct gtphub_peer_port *gtphub_resolve_ggsn_addr(struct gtphub *hub,
+ const char *imsi_str,
+ const char *apn_ni_str);
+int gtphub_ares_init(struct gtphub *hub);
+
+static void gtphub_zero(struct gtphub *hub)
+{
+ ZERO_STRUCT(hub);
+ INIT_LLIST_HEAD(&hub->ggsn_lookups);
+ INIT_LLIST_HEAD(&hub->resolved_ggsns);
+}
+
+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)
+{
+ if (!addr->addr_str) {
+ LOG(LOGL_FATAL, "Cannot bind: empty address.\n");
+ return -1;
+ }
+ if (!addr->port) {
+ LOG(LOGL_FATAL, "Cannot bind: zero port not permitted.\n");
+ return -1;
+ }
+
+ 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) {
+ LOG(LOGL_FATAL, "Cannot bind to %s port %d (rc %d)\n",
+ addr->addr_str, (int)addr->port, rc);
+ return -1;
+ }
+
+ return 0;
+}
+
+static void gtphub_sock_close(struct osmo_fd *ofd)
+{
+ close(ofd->fd);
+ osmo_fd_unregister(ofd);
+ ofd->cb = NULL;
+}
+
+static void gtphub_bind_init(struct gtphub_bind *b, uint32_t idx)
+{
+ ZERO_STRUCT(b);
+
+ INIT_LLIST_HEAD(&b->peers);
+
+ b->counters_io = rate_ctr_group_alloc(osmo_gtphub_ctx,
+ &gtphub_ctrg_io_desc, idx);
+ OSMO_ASSERT(b->counters_io);
+}
+
+static int gtphub_bind_start(struct gtphub_bind *b,
+ const struct gtphub_cfg_bind *cfg,
+ osmo_fd_cb_t cb, void *cb_data,
+ unsigned int ofd_id)
+{
+ LOG(LOGL_DEBUG, "Starting bind %s\n", b->label);
+ if (gsn_addr_from_str(&b->local_addr, cfg->bind.addr_str) != 0) {
+ LOG(LOGL_FATAL, "Invalid bind address for %s: %s\n",
+ b->label, cfg->bind.addr_str);
+ return -1;
+ }
+ if (gtphub_sock_init(&b->ofd, &cfg->bind, cb, cb_data, ofd_id) != 0) {
+ LOG(LOGL_FATAL, "Cannot bind for %s: %s\n",
+ b->label, cfg->bind.addr_str);
+ return -1;
+ }
+ b->local_port = cfg->bind.port;
+ return 0;
+}
+
+static void gtphub_bind_free(struct gtphub_bind *b)
+{
+ OSMO_ASSERT(llist_empty(&b->peers));
+ if (b->counters_io)
+ rate_ctr_group_free(b->counters_io);
+}
+
+static void gtphub_bind_stop(struct gtphub_bind *b) {
+ gtphub_sock_close(&b->ofd);
+ gtphub_bind_free(b);
+}
+
+/* Recv datagram from from->fd, write sender's address to *from_addr.
+ * Return the number of bytes read, zero on error. */
+static int gtphub_read(const struct osmo_fd *from,
+ struct osmo_sockaddr *from_addr,
+ uint8_t *buf, size_t buf_len)
+{
+ OSMO_ASSERT(from_addr);
+
+ /* recvfrom requires the available length set in *from_addr_len. */
+ from_addr->l = sizeof(from_addr->a);
+ errno = 0;
+ ssize_t received = recvfrom(from->fd, buf, buf_len, 0,
+ (struct sockaddr*)&from_addr->a,
+ &from_addr->l);
+ /* 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) {
+ LOG((errno == EAGAIN? LOGL_DEBUG : LOGL_ERROR),
+ "error: %s\n", strerror(errno));
+ return 0;
+ }
+
+ LOG(LOGL_DEBUG, "Received %d bytes from %s: %s%s\n",
+ (int)received, osmo_sockaddr_to_str(from_addr),
+ osmo_hexdump(buf, received > 1000? 1000 : received),
+ received > 1000 ? "..." : "");
+
+ return received;
+}
+
+static inline void gtphub_port_ref_count_inc(struct gtphub_peer_port *pp)
+{
+ OSMO_ASSERT(pp);
+ OSMO_ASSERT(pp->ref_count < UINT_MAX);
+ pp->ref_count++;
+}
+
+static inline void gtphub_port_ref_count_dec(struct gtphub_peer_port *pp)
+{
+ OSMO_ASSERT(pp);
+ OSMO_ASSERT(pp->ref_count > 0);
+ pp->ref_count--;
+}
+
+static inline void set_seq(struct gtp_packet_desc *p, uint16_t seq)
+{
+ OSMO_ASSERT(p->version == 1);
+ p->data->gtp1l.h.seq = hton16(seq);
+ p->seq = seq;
+}
+
+static inline void set_tei(struct gtp_packet_desc *p, uint32_t tei)
+{
+ OSMO_ASSERT(p->version == 1);
+ p->data->gtp1l.h.tei = hton32(tei);
+ p->header_tei = tei;
+}
+
+static void gtphub_mapping_del_cb(struct expiring_item *expi);
+
+static struct nr_mapping *gtphub_mapping_new()
+{
+ struct nr_mapping *nrm;
+ nrm = talloc_zero(osmo_gtphub_ctx, struct nr_mapping);
+ OSMO_ASSERT(nrm);
+
+ nr_mapping_init(nrm);
+ nrm->expiry_entry.del_cb = gtphub_mapping_del_cb;
+ return nrm;
+}
+
+
+#define APPEND(args...) \
+ l = snprintf(pos, left, args); \
+ pos += l; \
+ left -= l
+
+static const char *gtphub_tunnel_side_str(struct gtphub_tunnel *tun,
+ int side_idx)
+{
+ static char buf[256];
+ char *pos = buf;
+ int left = sizeof(buf);
+ int l;
+
+ struct gtphub_tunnel_endpoint *c, *u;
+ c = &tun->endpoint[side_idx][GTPH_PLANE_CTRL];
+ u = &tun->endpoint[side_idx][GTPH_PLANE_USER];
+
+ /* print both only if they differ. */
+ if (!c->peer) {
+ APPEND("(uninitialized)");
+ } else {
+ APPEND("%s", gsn_addr_to_str(&c->peer->peer_addr->addr));
+ }
+
+ if (!u->peer) {
+ if (c->peer) {
+ APPEND("/(uninitialized)");
+ }
+ } else if ((!c->peer)
+ || (!gsn_addr_same(&u->peer->peer_addr->addr,
+ &c->peer->peer_addr->addr))) {
+ APPEND("/%s", gsn_addr_to_str(&u->peer->peer_addr->addr));
+ }
+
+ APPEND(" (TEI C=%x U=%x)",
+ c->tei_orig,
+ u->tei_orig);
+ return buf;
+}
+
+const char *gtphub_tunnel_str(struct gtphub_tunnel *tun)
+{
+ static char buf[512];
+ char *pos = buf;
+ int left = sizeof(buf);
+ int l;
+
+ if (!tun)
+ return "null-tunnel";
+
+ APPEND("TEI=%x: ", tun->tei_repl);
+ APPEND("%s", gtphub_tunnel_side_str(tun, GTPH_SIDE_SGSN));
+ APPEND(" <-> %s", gtphub_tunnel_side_str(tun, GTPH_SIDE_GGSN));
+
+ return buf;
+}
+
+#undef APPEND
+
+void gtphub_tunnel_endpoint_set_peer(struct gtphub_tunnel_endpoint *te,
+ struct gtphub_peer_port *pp)
+{
+ if (te->peer)
+ gtphub_port_ref_count_dec(te->peer);
+ te->peer = pp;
+ if (te->peer)
+ gtphub_port_ref_count_inc(te->peer);
+}
+
+int gtphub_tunnel_complete(struct gtphub_tunnel *tun)
+{
+ if (!tun)
+ return 0;
+ if (!tun->tei_repl)
+ return 0;
+ int side_idx;
+ int plane_idx;
+ for_each_side_and_plane(side_idx, plane_idx) {
+ struct gtphub_tunnel_endpoint *te =
+ &tun->endpoint[side_idx][plane_idx];
+ if (!(te->peer && te->tei_orig))
+ return 0;
+ }
+ return 1;
+}
+
+static void gtphub_tunnel_del_cb(struct expiring_item *expi)
+{
+ struct gtphub_tunnel *tun = container_of(expi,
+ struct gtphub_tunnel,
+ expiry_entry);
+ LOG(LOGL_DEBUG, "expired: %s\n", gtphub_tunnel_str(tun));
+
+ llist_del(&tun->entry);
+ INIT_LLIST_HEAD(&tun->entry); /* mark unused */
+
+ expi->del_cb = 0; /* avoid recursion loops */
+ expiring_item_del(&tun->expiry_entry); /* usually already done, but make sure. */
+
+ int side_idx;
+ int plane_idx;
+ for_each_side_and_plane(side_idx, plane_idx) {
+ struct gtphub_tunnel_endpoint *te = &tun->endpoint[side_idx][plane_idx];
+
+ /* clear ref count */
+ gtphub_tunnel_endpoint_set_peer(te, NULL);
+
+ rate_ctr_group_free(te->counters_io);
+ }
+
+ talloc_free(tun);
+}
+
+#define CTR_IDX(s, p, a, b) (a + s + (p + b) * 2)
+
+/* rate counter index for tunnels: [3; 6] */
+#define CTR_IDX_TUN(s, p) CTR_IDX(s, p, 1, 1)
+
+/* rate counter index for hubs: [7; 10] */
+#define CTR_IDX_HUB(s, p) CTR_IDX(s, p, 3, 2)
+
+static struct gtphub_tunnel *gtphub_tunnel_new()
+{
+ struct gtphub_tunnel *tun;
+ tun = talloc_zero(osmo_gtphub_ctx, struct gtphub_tunnel);
+ OSMO_ASSERT(tun);
+
+ INIT_LLIST_HEAD(&tun->entry);
+ expiring_item_init(&tun->expiry_entry);
+
+ int side_idx, plane_idx;
+ for_each_side_and_plane(side_idx, plane_idx) {
+ struct gtphub_tunnel_endpoint *te = &tun->endpoint[side_idx][plane_idx];
+ te->counters_io = rate_ctr_group_alloc(osmo_gtphub_ctx,
+ &gtphub_ctrg_io_desc,
+ CTR_IDX_TUN(side_idx, plane_idx));
+ if (!te->counters_io)
+ return NULL;
+ }
+
+ tun->expiry_entry.del_cb = gtphub_tunnel_del_cb;
+ return tun;
+}
+
+static const char *gtphub_peer_strb(struct gtphub_peer *peer, char *buf,
+ int buflen)
+{
+ if (llist_empty(&peer->addresses))
+ return "(addressless)";
+
+ struct gtphub_peer_addr *a = llist_first(&peer->addresses,
+ struct gtphub_peer_addr,
+ entry);
+ return gsn_addr_to_strb(&a->addr, buf, buflen);
+}
+
+static const char *gtphub_port_strb(struct gtphub_peer_port *port, char *buf,
+ int buflen)
+{
+ if (!port)
+ return "(null port)";
+
+ snprintf(buf, buflen, "%s port %d",
+ gsn_addr_to_str(&port->peer_addr->addr),
+ (int)port->port);
+ return buf;
+}
+
+const char *gtphub_peer_str(struct gtphub_peer *peer)
+{
+ static char buf[256];
+ return gtphub_peer_strb(peer, buf, sizeof(buf));
+}
+
+const char *gtphub_port_str(struct gtphub_peer_port *port)
+{
+ static char buf[256];
+ return gtphub_port_strb(port, buf, sizeof(buf));
+}
+
+static const char *gtphub_port_str2(struct gtphub_peer_port *port)
+{
+ static char buf[256];
+ return gtphub_port_strb(port, buf, sizeof(buf));
+}
+
+static void gtphub_mapping_del_cb(struct expiring_item *expi)
+{
+ expi->del_cb = 0; /* avoid recursion loops */
+ expiring_item_del(expi); /* usually already done, but make sure. */
+
+ struct nr_mapping *nrm = container_of(expi,
+ struct nr_mapping,
+ expiry_entry);
+ llist_del(&nrm->entry);
+ INIT_LLIST_HEAD(&nrm->entry); /* mark unused */
+
+ /* Just for log */
+ struct gtphub_peer_port *from = nrm->origin;
+ OSMO_ASSERT(from);
+ LOG(LOGL_DEBUG, "expired: %d: nr mapping from %s: %u->%u\n",
+ (int)nrm->expiry_entry.expiry,
+ gtphub_port_str(from),
+ (unsigned int)nrm->orig, (unsigned int)nrm->repl);
+
+ gtphub_port_ref_count_dec(from);
+
+ talloc_free(nrm);
+}
+
+static struct nr_mapping *gtphub_mapping_have(struct nr_map *map,
+ struct gtphub_peer_port *from,
+ nr_t orig_nr,
+ time_t now)
+{
+ struct nr_mapping *nrm;
+
+ nrm = nr_map_get(map, from, orig_nr);
+
+ if (!nrm) {
+ nrm = gtphub_mapping_new();
+ nrm->orig = orig_nr;
+ nrm->origin = from;
+ nr_map_add(map, nrm, now);
+ gtphub_port_ref_count_inc(from);
+ LOG(LOGL_DEBUG, "peer %s: sequence map %d --> %d\n",
+ gtphub_port_str(from),
+ (int)(nrm->orig), (int)(nrm->repl));
+ } else {
+ nr_map_refresh(map, nrm, now);
+ }
+
+ OSMO_ASSERT(nrm);
+ return nrm;
+}
+
+static void gtphub_map_seq(struct gtp_packet_desc *p,
+ struct gtphub_peer_port *from_port,
+ struct gtphub_peer_port *to_port)
+{
+ /* Store a mapping in to_peer's map, so when we later receive a GTP
+ * packet back from to_peer, the seq nr can be unmapped back to its
+ * origin (from_peer here). */
+ struct nr_mapping *nrm;
+ nrm = gtphub_mapping_have(&to_port->peer_addr->peer->seq_map,
+ from_port, p->seq, p->timestamp);
+
+ /* Change the GTP packet to yield the new, mapped seq nr */
+ set_seq(p, nrm->repl);
+}
+
+static struct gtphub_peer_port *gtphub_unmap_seq(struct gtp_packet_desc *p,
+ struct gtphub_peer_port *responding_port)
+{
+ OSMO_ASSERT(p->version == 1);
+ struct nr_mapping *nrm =
+ nr_map_get_inv(&responding_port->peer_addr->peer->seq_map,
+ p->seq);
+ if (!nrm)
+ return NULL;
+ LOG(LOGL_DEBUG, "peer %p: sequence unmap %d <-- %d\n",
+ nrm->origin, (int)(nrm->orig), (int)(nrm->repl));
+ set_seq(p, nrm->orig);
+ return nrm->origin;
+}
+
+static int gtphub_check_mapped_tei(struct gtphub_tunnel *new_tun,
+ struct gtphub_tunnel *iterated_tun,
+ uint32_t *tei_min,
+ uint32_t *tei_max)
+{
+ if (!new_tun->tei_repl || !iterated_tun->tei_repl)
+ return 1;
+
+ *tei_min = (*tei_min < iterated_tun->tei_repl)? *tei_min : iterated_tun->tei_repl;
+ *tei_max = (*tei_max > iterated_tun->tei_repl)? *tei_max : iterated_tun->tei_repl;
+
+ if (new_tun->tei_repl != iterated_tun->tei_repl)
+ return 1;
+
+ /* new_tun->tei_repl is already taken. Try to find one out of the known
+ * range. */
+ LOG(LOGL_DEBUG, "TEI replacement %d already taken.\n", new_tun->tei_repl);
+
+ if ((*tei_max) < 0xffffffff) {
+ (*tei_max)++;
+ new_tun->tei_repl = *tei_max;
+ LOG(LOGL_DEBUG, "Using TEI %d instead.\n", new_tun->tei_repl);
+ return 1;
+ } else if ((*tei_min) > 1) {
+ (*tei_min)--;
+ new_tun->tei_repl = *tei_min;
+ LOG(LOGL_DEBUG, "Using TEI %d instead.\n", new_tun->tei_repl);
+ return 1;
+ }
+
+ /* None seems to be available. */
+ return 0;
+}
+
+static int gtphub_check_reused_teis(struct gtphub *hub,
+ struct gtphub_tunnel *new_tun)
+{
+ uint32_t tei_min = 0xffffffff;
+ uint32_t tei_max = 0;
+ int side_idx;
+ int plane_idx;
+ struct gtphub_tunnel_endpoint *te;
+ struct gtphub_tunnel_endpoint *te2;
+
+ struct gtphub_tunnel *tun, *ntun;
+
+ llist_for_each_entry_safe(tun, ntun, &hub->tunnels, entry) {
+ if (tun == new_tun)
+ continue;
+
+ /* Check whether the GSN sent a TEI that it is reusing from a
+ * previous tunnel. */
+ int tun_continue = 0;
+ for_each_side(side_idx) {
+ for_each_plane(plane_idx) {
+ te = &tun->endpoint[side_idx][plane_idx];
+ te2 = &new_tun->endpoint[side_idx][plane_idx];
+ if ((te->tei_orig == 0)
+ || (te->tei_orig != te2->tei_orig)
+ || (!te->peer)
+ || (!te2->peer)
+ || !gsn_addr_same(&te->peer->peer_addr->addr,
+ &te2->peer->peer_addr->addr))
+ continue;
+
+ /* The peer is reusing a TEI that I believe to
+ * be part of another tunnel. The other tunnel
+ * must be stale, then. */
+ LOG(LOGL_NOTICE,
+ "Expiring tunnel due to reused TEI:"
+ " %s peer %s sent %s TEI %x,"
+ " previously used by tunnel %s...\n",
+ gtphub_side_idx_names[side_idx],
+ gtphub_port_str(te->peer),
+ gtphub_plane_idx_names[plane_idx],
+ te->tei_orig,
+ gtphub_tunnel_str(tun));
+ LOG(LOGL_NOTICE, "...while establishing tunnel %s\n",
+ gtphub_tunnel_str(new_tun));
+
+ expiring_item_del(&tun->expiry_entry);
+ /* continue to find more matches. There shouldn't be
+ * any, but let's make sure. However, tun is deleted,
+ * so we need to skip to the next tunnel. */
+ tun_continue = 1;
+ break;
+ }
+ if (tun_continue)
+ break;
+ }
+ if (tun_continue)
+ continue;
+
+ /* Check whether the mapped TEI is already used by another
+ * tunnel. */
+ if (!gtphub_check_mapped_tei(new_tun, tun, &tei_min, &tei_max)) {
+ LOG(LOGL_ERROR,
+ "No mapped TEI is readily available."
+ " Searching for holes between occupied"
+ " TEIs not implemented.");
+ return 0;
+ }
+
+ }
+
+ return 1;
+}
+
+static void gtphub_tunnel_refresh(struct gtphub *hub,
+ struct gtphub_tunnel *tun,
+ time_t now)
+{
+ expiry_add(&hub->expire_slowly,
+ &tun->expiry_entry,
+ now);
+}
+
+static struct gtphub_tunnel_endpoint *gtphub_unmap_tei(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port *from,
+ struct gtphub_tunnel **unmapped_from_tun)
+{
+ OSMO_ASSERT(from);
+ int other_side = other_side_idx(p->side_idx);
+
+ struct gtphub_tunnel *tun;
+ llist_for_each_entry(tun, &hub->tunnels, entry) {
+ struct gtphub_tunnel_endpoint *te_from =
+ &tun->endpoint[p->side_idx][p->plane_idx];
+ struct gtphub_tunnel_endpoint *te_to =
+ &tun->endpoint[other_side][p->plane_idx];
+ if ((tun->tei_repl == p->header_tei_rx)
+ && te_from->peer
+ && gsn_addr_same(&te_from->peer->peer_addr->addr,
+ &from->peer_addr->addr)) {
+ gtphub_tunnel_refresh(hub, tun, p->timestamp);
+ if (unmapped_from_tun)
+ *unmapped_from_tun = tun;
+ return te_to;
+ }
+ }
+
+ if (unmapped_from_tun)
+ *unmapped_from_tun = NULL;
+ return NULL;
+}
+
+static void gtphub_map_restart_counter(struct gtphub *hub,
+ struct gtp_packet_desc *p)
+{
+ if (p->rc != GTP_RC_PDU_C)
+ return;
+
+ int ie_idx;
+ ie_idx = gtpie_getie(p->ie, GTPIE_RECOVERY, 0);
+ if (ie_idx < 0)
+ return;
+
+ /* Always send gtphub's own restart counter */
+ p->ie[ie_idx]->tv1.v = hton8(hub->restart_counter);
+}
+
+static int gtphub_unmap_header_tei(struct gtphub_peer_port **to_port_p,
+ struct gtphub_tunnel **unmapped_from_tun,
+ struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port *from_port)
+{
+ OSMO_ASSERT(p->version == 1);
+ *to_port_p = NULL;
+ if (unmapped_from_tun)
+ *unmapped_from_tun = NULL;
+
+ /* If the header's TEI is zero, no PDP context has been established
+ * yet. If nonzero, a mapping should actually already exist for this
+ * TEI, since it must have been announced in a PDP context creation. */
+ if (!p->header_tei_rx)
+ return 0;
+
+ /* to_peer has previously announced a TEI, which was stored and
+ * mapped in a tunnel struct. */
+ struct gtphub_tunnel_endpoint *to;
+ to = gtphub_unmap_tei(hub, p, from_port, unmapped_from_tun);
+ if (!to) {
+ LOG(LOGL_ERROR, "Received unknown TEI %" PRIx32 " from %s\n",
+ p->header_tei_rx, gtphub_port_str(from_port));
+ return -1;
+ }
+
+ if (unmapped_from_tun) {
+ OSMO_ASSERT(*unmapped_from_tun);
+ LOG(LOGL_DEBUG, "Unmapped TEI coming from: %s\n",
+ gtphub_tunnel_str(*unmapped_from_tun));
+ }
+
+ uint32_t unmapped_tei = to->tei_orig;
+ set_tei(p, unmapped_tei);
+
+ /* May be NULL for an invalidated tunnel. */
+ *to_port_p = to->peer;
+
+ return 0;
+}
+
+static int gtphub_handle_create_pdp_ctx(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port *from_ctrl,
+ struct gtphub_peer_port *to_ctrl)
+{
+ int plane_idx;
+
+ osmo_static_assert((GTPH_PLANE_CTRL == 0) && (GTPH_PLANE_USER == 1),
+ plane_nrs_match_GSN_addr_IE_indices);
+
+ struct gtphub_tunnel *tun = p->tun;
+
+ if (p->type == GTP_CREATE_PDP_REQ) {
+ if (p->side_idx != GTPH_SIDE_SGSN) {
+ LOG(LOGL_ERROR, "Wrong side: Create PDP Context"
+ " Request from the GGSN side: %s",
+ gtphub_port_str(from_ctrl));
+ return -1;
+ }
+
+ if (tun) {
+ LOG(LOGL_ERROR, "Not implemented: Received"
+ " Create PDP Context Request for an already"
+ " established tunnel:"
+ " from %s, tunnel %s\n",
+ gtphub_port_str(from_ctrl),
+ gtphub_tunnel_str(p->tun));
+ return -1;
+ }
+
+ /* A new tunnel. */
+ tun = gtphub_tunnel_new();
+ if (!tun) {
+ LOG(LOGL_ERROR, "Failed to allocate new tunnel %s <-> %s\n",
+ gtphub_port_str(from_ctrl), gtphub_port_str(to_ctrl));
+ return -1;
+ }
+ p->tun = tun;
+
+ /* Create TEI mapping */
+ tun->tei_repl = nr_pool_next(&hub->tei_pool);
+
+ llist_add(&tun->entry, &hub->tunnels);
+ gtphub_tunnel_refresh(hub, tun, p->timestamp);
+ /* The endpoint peers on this side (SGSN) will be set from IEs
+ * below. Also set the GGSN Ctrl endpoint, for logging. */
+ gtphub_tunnel_endpoint_set_peer(&tun->endpoint[GTPH_SIDE_GGSN][GTPH_PLANE_CTRL],
+ to_ctrl);
+ } else if (p->type == GTP_CREATE_PDP_RSP) {
+ if (p->side_idx != GTPH_SIDE_GGSN) {
+ LOG(LOGL_ERROR, "Wrong side: Create PDP Context"
+ " Response from the SGSN side: %s",
+ gtphub_port_str(from_ctrl));
+ return -1;
+ }
+
+ /* The tunnel should already have been resolved from the header
+ * TEI and be available in tun (== p->tun). Just fill in the
+ * GSN Addresses below.*/
+ OSMO_ASSERT(tun);
+ OSMO_ASSERT(tun->tei_repl == p->header_tei_rx);
+ OSMO_ASSERT(to_ctrl);
+ }
+
+ uint8_t ie_type[] = { GTPIE_TEI_C, GTPIE_TEI_DI };
+ int ie_mandatory = (p->type == GTP_CREATE_PDP_REQ);
+ unsigned int side_idx = p->side_idx;
+
+ for_each_plane(plane_idx) {
+ int rc;
+ struct gsn_addr use_addr;
+ uint16_t use_port;
+ uint32_t tei_from_ie;
+ int ie_idx;
+
+ /* Fetch GSN Address and TEI from IEs. As ensured by above
+ * static asserts, plane_idx corresponds to the GSN Address IE
+ * index (the first one = 0 = ctrl, second one = 1 = user). */
+ rc = gsn_addr_get(&use_addr, p, plane_idx);
+ if (rc) {
+ LOG(LOGL_ERROR, "Cannot read %s GSN Address IE\n",
+ gtphub_plane_idx_names[plane_idx]);
+ return -1;
+ }
+ LOG(LOGL_DEBUG, "Read %s GSN addr %s (%d)\n",
+ gtphub_plane_idx_names[plane_idx],
+ gsn_addr_to_str(&use_addr),
+ use_addr.len);
+
+ ie_idx = gtpie_getie(p->ie, ie_type[plane_idx], 0);
+ if (ie_idx < 0) {
+ if (ie_mandatory) {
+ LOG(LOGL_ERROR,
+ "Create PDP Context message invalid:"
+ " missing IE %d\n",
+ (int)ie_type[plane_idx]);
+ return -1;
+ }
+ tei_from_ie = 0;
+ }
+ else
+ tei_from_ie = ntoh32(p->ie[ie_idx]->tv4.v);
+
+ /* Make sure an entry for this peer address with default port
+ * exists.
+ *
+ * Exception: if sgsn_use_sender is set, instead use the
+ * sender's address and port for Ctrl -- the User port is not
+ * known until the first User packet arrives.
+ *
+ * Note: doing this here is just an optimization, because
+ * gtphub_handle_buf() has code to replace the tunnel
+ * endpoints' addresses with the sender (needed for User
+ * plane). We could just ignore sgsn_use_sender here. But if we
+ * set up a default port here and replace it in
+ * gtphub_handle_buf(), we'd be creating a peer port just to
+ * expire it right away. */
+ if (hub->sgsn_use_sender && (side_idx == GTPH_SIDE_SGSN)) {
+ int rc = gsn_addr_from_sockaddr(&use_addr, &use_port, &from_ctrl->sa);
+ if (rc < 0)
+ LOG(LOGL_ERROR, "%s(): failed to obtain GSN address\n", __func__);
+ } else {
+ use_port = gtphub_plane_idx_default_port[plane_idx];
+
+ }
+
+ struct gtphub_peer_port *peer_from_ie;
+ peer_from_ie = gtphub_port_have(hub,
+ &hub->to_gsns[side_idx][plane_idx],
+ &use_addr, use_port);
+
+ gtphub_tunnel_endpoint_set_peer(&tun->endpoint[side_idx][plane_idx],
+ peer_from_ie);
+
+ if (!tei_from_ie &&
+ !tun->endpoint[side_idx][plane_idx].tei_orig) {
+ LOG(LOGL_ERROR,
+ "Create PDP Context message omits %s TEI, but"
+ " no TEI has been announced for this tunnel: %s\n",
+ gtphub_plane_idx_names[plane_idx],
+ gtphub_tunnel_str(tun));
+ return -1;
+ }
+
+ if (tei_from_ie) {
+ /* Replace TEI in GTP packet IE */
+ tun->endpoint[side_idx][plane_idx].tei_orig = tei_from_ie;
+ p->ie[ie_idx]->tv4.v = hton32(tun->tei_repl);
+
+ if (!gtphub_check_reused_teis(hub, tun)) {
+ /* It's highly unlikely that all TEIs are
+ * taken. But the code looking for an unused
+ * TEI is, at the time of writing this comment,
+ * not able to find gaps in the TEI space. To
+ * explicitly alert the user of this problem,
+ * rather abort than carry on. */
+ LOG(LOGL_FATAL, "TEI range exhausted. Cannot create TEI mapping, aborting.\n");
+ abort();
+ }
+ }
+
+ /* Replace the GSN address to reflect gtphub. */
+ rc = gsn_addr_put(&hub->to_gsns[other_side_idx(side_idx)][plane_idx].local_addr,
+ p, plane_idx);
+ if (rc) {
+ LOG(LOGL_ERROR, "Cannot write %s GSN Address IE\n",
+ gtphub_plane_idx_names[plane_idx]);
+ return -1;
+ }
+ }
+
+ if (p->type == GTP_CREATE_PDP_REQ) {
+ LOG(LOGL_DEBUG, "New tunnel, first half: %s\n",
+ gtphub_tunnel_str(tun));
+ } else if (p->type == GTP_CREATE_PDP_RSP) {
+ LOG(LOGL_DEBUG, "New tunnel: %s\n",
+ gtphub_tunnel_str(tun));
+ }
+
+ return 0;
+}
+
+static void pending_delete_del_cb(struct expiring_item *expi)
+{
+ struct pending_delete *pd;
+ pd = container_of(expi, struct pending_delete, expiry_entry);
+
+ llist_del(&pd->entry);
+ INIT_LLIST_HEAD(&pd->entry);
+
+ pd->expiry_entry.del_cb = 0;
+ expiring_item_del(&pd->expiry_entry);
+
+ talloc_free(pd);
+}
+
+static struct pending_delete *pending_delete_new(void)
+{
+ struct pending_delete *pd = talloc_zero(osmo_gtphub_ctx, struct pending_delete);
+ INIT_LLIST_HEAD(&pd->entry);
+ expiring_item_init(&pd->expiry_entry);
+ pd->expiry_entry.del_cb = pending_delete_del_cb;
+ return pd;
+}
+
+static int gtphub_handle_delete_pdp_ctx(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port *from_ctrl,
+ struct gtphub_peer_port *to_ctrl)
+{
+ struct gtphub_tunnel *known_tun = p->tun;
+
+ if (p->type == GTP_DELETE_PDP_REQ) {
+ if (!known_tun) {
+ LOG(LOGL_ERROR, "Cannot find tunnel for Delete PDP Context Request.\n");
+ return -1;
+ }
+
+ /* Store the Delete Request until a successful Response is seen. */
+ uint8_t teardown_ind;
+ uint8_t nsapi;
+
+ if (gtpie_gettv1(p->ie, GTPIE_TEARDOWN, 0, &teardown_ind) != 0) {
+ LOG(LOGL_ERROR, "Missing Teardown Ind IE in Delete PDP Context Request.\n");
+ return -1;
+ }
+
+ if (gtpie_gettv1(p->ie, GTPIE_NSAPI, 0, &nsapi) != 0) {
+ LOG(LOGL_ERROR, "Missing NSAPI IE in Delete PDP Context Request.\n");
+ return -1;
+ }
+
+ struct pending_delete *pd = NULL;
+
+ struct pending_delete *pdi = NULL;
+ llist_for_each_entry(pdi, &hub->pending_deletes, entry) {
+ if ((pdi->tun == known_tun)
+ && (pdi->teardown_ind == teardown_ind)
+ && (pdi->nsapi == nsapi)) {
+ pd = pdi;
+ break;
+ }
+ }
+
+ if (!pd) {
+ pd = pending_delete_new();
+ pd->tun = known_tun;
+ pd->teardown_ind = teardown_ind;
+ pd->nsapi = nsapi;
+
+ LOG(LOGL_DEBUG, "Tunnel delete pending: %s\n",
+ gtphub_tunnel_str(known_tun));
+ llist_add(&pd->entry, &hub->pending_deletes);
+ }
+
+ /* Add or refresh timeout. */
+ expiry_add(&hub->expire_quickly, &pd->expiry_entry, p->timestamp);
+
+ /* If a pending_delete should expire before the response to
+ * indicate success comes in, the responding peer will have the
+ * tunnel deactivated, while the requesting peer gets no reply
+ * and keeps the tunnel. The hope is that the requesting peer
+ * will try again and get a useful response. */
+ } else if (p->type == GTP_DELETE_PDP_RSP) {
+ /* Find the Delete Request for this Response. */
+ struct pending_delete *pd = NULL;
+
+ struct pending_delete *pdi;
+ llist_for_each_entry(pdi, &hub->pending_deletes, entry) {
+ if (known_tun == pdi->tun) {
+ pd = pdi;
+ break;
+ }
+ }
+
+ if (!pd) {
+ LOG(LOGL_ERROR, "Delete PDP Context Response:"
+ " Cannot find matching request.");
+ /* If we delete the tunnel now, anyone can send a
+ * Delete response to kill tunnels at will. */
+ return -1;
+ }
+
+ /* TODO handle teardown_ind and nsapi */
+
+ expiring_item_del(&pd->expiry_entry);
+
+ uint8_t cause;
+ if (gtpie_gettv1(p->ie, GTPIE_CAUSE, 0, &cause) != 0) {
+ LOG(LOGL_ERROR, "Delete PDP Context Response:"
+ " Missing Cause IE.");
+ /* If we delete the tunnel now, at least one of the
+ * peers may still think it is active. */
+ return -1;
+ }
+
+ if (cause != GTPCAUSE_ACC_REQ) {
+ LOG(LOGL_NOTICE,
+ "Delete PDP Context Response indicates failure;"
+ "for %s\n",
+ gtphub_tunnel_str(known_tun));
+ return -1;
+ }
+
+ LOG(LOGL_DEBUG, "Delete PDP Context: removing tunnel %s\n",
+ gtphub_tunnel_str(known_tun));
+ p->tun = NULL;
+ expiring_item_del(&known_tun->expiry_entry);
+ }
+
+ return 0;
+}
+
+static int gtphub_handle_update_pdp_ctx(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port *from_ctrl,
+ struct gtphub_peer_port *to_ctrl)
+{
+ /* TODO */
+ return 0;
+}
+
+/* Read GSN address IEs from p, and make sure these peer addresses exist in
+ * bind[plane_idx] with default ports, in their respective planes (both Ctrl
+ * and User). Map TEIs announced in IEs, and write mapped TEIs in-place into
+ * the packet p. */
+static int gtphub_handle_pdp_ctx(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port *from_ctrl,
+ struct gtphub_peer_port *to_ctrl)
+{
+ OSMO_ASSERT(p->plane_idx == GTPH_PLANE_CTRL);
+
+ switch (p->type) {
+ case GTP_CREATE_PDP_REQ:
+ case GTP_CREATE_PDP_RSP:
+ return gtphub_handle_create_pdp_ctx(hub, p,
+ from_ctrl, to_ctrl);
+
+ case GTP_DELETE_PDP_REQ:
+ case GTP_DELETE_PDP_RSP:
+ return gtphub_handle_delete_pdp_ctx(hub, p,
+ from_ctrl, to_ctrl);
+
+ case GTP_UPDATE_PDP_REQ:
+ case GTP_UPDATE_PDP_RSP:
+ return gtphub_handle_update_pdp_ctx(hub, p,
+ from_ctrl, to_ctrl);
+
+ default:
+ /* Nothing to do for this message type. */
+ return 0;
+ }
+
+}
+
+static int gtphub_send_del_pdp_ctx(struct gtphub *hub,
+ struct gtphub_tunnel *tun,
+ int to_side)
+{
+ static uint8_t del_ctx_msg[16] = {
+ 0x32, /* GTP v1 flags */
+ GTP_DELETE_PDP_REQ,
+ 0x00, 0x08, /* Length in network byte order */
+ 0x00, 0x00, 0x00, 0x00, /* TEI to be replaced */
+ 0, 0, /* Seq, to be replaced */
+ 0, 0, /* no extensions */
+ 0x13, 0xff, /* 19: Teardown ind = 1 */
+ 0x14, 0 /* 20: NSAPI = 0 */
+ };
+
+ uint32_t *tei = (uint32_t*)&del_ctx_msg[4];
+ uint16_t *seq = (uint16_t*)&del_ctx_msg[8];
+
+ struct gtphub_tunnel_endpoint *te =
+ &tun->endpoint[to_side][GTPH_PLANE_CTRL];
+
+ if (! te->peer)
+ return 0;
+
+ *tei = hton32(te->tei_orig);
+ *seq = hton16(nr_pool_next(&te->peer->peer_addr->peer->seq_pool));
+
+ struct gtphub_bind *to_bind = &hub->to_gsns[to_side][GTPH_PLANE_CTRL];
+ int rc = gtphub_write(&to_bind->ofd, &te->peer->sa,
+ del_ctx_msg, sizeof(del_ctx_msg));
+ if (rc != 0) {
+ LOG(LOGL_ERROR,
+ "Failed to send out-of-band Delete PDP Context Request to %s\n",
+ gtphub_port_str(te->peer));
+ }
+ return rc;
+}
+
+/* Tell all peers on the other end of tunnels that PDP contexts are void. */
+static void gtphub_restarted(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port *pp)
+{
+ LOG(LOGL_NOTICE, "Peer has restarted: %s\n",
+ gtphub_port_str(pp));
+
+ int deleted_count = 0;
+ struct gtphub_tunnel *tun;
+ llist_for_each_entry(tun, &hub->tunnels, entry) {
+ int side_idx;
+ for_each_side(side_idx) {
+ struct gtphub_tunnel_endpoint *te = &tun->endpoint[side_idx][GTPH_PLANE_CTRL];
+ struct gtphub_tunnel_endpoint *te2 = &tun->endpoint[other_side_idx(side_idx)][GTPH_PLANE_CTRL];
+ if ((!te->peer)
+ || (!te2->tei_orig)
+ || (pp->peer_addr->peer != te->peer->peer_addr->peer))
+ continue;
+
+ LOG(LOGL_DEBUG, "Deleting tunnel due to peer restart: %s\n",
+ gtphub_tunnel_str(tun));
+ deleted_count ++;
+
+ /* Send a Delete PDP Context Request to the
+ * peer on the other side, remember the pending
+ * delete and wait for the response to delete
+ * the tunnel. Clear this side of the tunnel to
+ * make sure it isn't used.
+ *
+ * Should the delete message send fail, or if no
+ * response is received, this tunnel will expire. If
+ * its TEIs come up in a new PDP Context Request, it
+ * will be removed. If messages for this tunnel should
+ * come in (from the not restarted side), they will be
+ * dropped because the tunnel is rendered unusable. */
+ gtphub_send_del_pdp_ctx(hub, tun, other_side_idx(side_idx));
+
+ gtphub_tunnel_endpoint_set_peer(&tun->endpoint[side_idx][GTPH_PLANE_CTRL],
+ NULL);
+ gtphub_tunnel_endpoint_set_peer(&tun->endpoint[side_idx][GTPH_PLANE_USER],
+ NULL);
+ }
+ }
+
+ if (deleted_count)
+ LOG(LOGL_NOTICE, "Deleting %d tunnels due to restart of: %s\n",
+ deleted_count,
+ gtphub_port_str(pp));
+}
+
+static int get_restart_count(struct gtp_packet_desc *p)
+{
+ int ie_idx;
+ ie_idx = gtpie_getie(p->ie, GTPIE_RECOVERY, 0);
+ if (ie_idx < 0)
+ return -1;
+ return ntoh8(p->ie[ie_idx]->tv1.v);
+}
+
+static void gtphub_check_restart_counter(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port *from)
+{
+ /* If the peer is sending a Recovery IE (7.7.11) with a restart counter
+ * that doesn't match the peer's previously sent restart counter, clear
+ * that peer and cancel PDP contexts. */
+
+ int restart = get_restart_count(p);
+
+ if ((restart < 0) || (restart > 255))
+ return;
+
+ if ((from->last_restart_count >= 0) && (from->last_restart_count <= 255)) {
+ if (from->last_restart_count != restart) {
+ gtphub_restarted(hub, p, from);
+ }
+ }
+
+ from->last_restart_count = restart;
+}
+
+static int from_sgsns_read_cb(struct osmo_fd *from_sgsns_ofd, unsigned int what)
+{
+ unsigned int plane_idx = from_sgsns_ofd->priv_nr;
+ OSMO_ASSERT(plane_idx < GTPH_PLANE_N);
+ LOG(LOGL_DEBUG, "=== reading from SGSN (%s)\n",
+ gtphub_plane_idx_names[plane_idx]);
+
+ if (!(what & BSC_FD_READ))
+ return 0;
+
+ struct gtphub *hub = from_sgsns_ofd->data;
+
+ static uint8_t buf[4096];
+ struct osmo_sockaddr from_addr;
+ struct osmo_sockaddr to_addr;
+ struct osmo_fd *to_ofd;
+ int len;
+ uint8_t *reply_buf;
+
+ len = gtphub_read(from_sgsns_ofd, &from_addr, buf, sizeof(buf));
+ if (len < 1)
+ return 0;
+
+ len = gtphub_handle_buf(hub, GTPH_SIDE_SGSN, plane_idx, &from_addr,
+ buf, len, gtphub_now(),
+ &reply_buf, &to_ofd, &to_addr);
+ if (len < 1)
+ return 0;
+
+ return gtphub_write(to_ofd, &to_addr, reply_buf, len);
+}
+
+static int from_ggsns_read_cb(struct osmo_fd *from_ggsns_ofd, unsigned int what)
+{
+ unsigned int plane_idx = from_ggsns_ofd->priv_nr;
+ OSMO_ASSERT(plane_idx < GTPH_PLANE_N);
+ LOG(LOGL_DEBUG, "=== reading from GGSN (%s)\n",
+ gtphub_plane_idx_names[plane_idx]);
+ if (!(what & BSC_FD_READ))
+ return 0;
+
+ struct gtphub *hub = from_ggsns_ofd->data;
+
+ static uint8_t buf[4096];
+ struct osmo_sockaddr from_addr;
+ struct osmo_sockaddr to_addr;
+ struct osmo_fd *to_ofd;
+ int len;
+ uint8_t *reply_buf;
+
+ len = gtphub_read(from_ggsns_ofd, &from_addr, buf, sizeof(buf));
+ if (len < 1)
+ return 0;
+
+ len = gtphub_handle_buf(hub, GTPH_SIDE_GGSN, plane_idx, &from_addr,
+ buf, len, gtphub_now(),
+ &reply_buf, &to_ofd, &to_addr);
+ if (len < 1)
+ return 0;
+
+ return gtphub_write(to_ofd, &to_addr, reply_buf, len);
+}
+
+static int gtphub_unmap(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port *from,
+ struct gtphub_peer_port *to_proxy,
+ struct gtphub_peer_port **final_unmapped,
+ struct gtphub_peer_port **unmapped_from_seq)
+{
+ /* Always (try to) unmap sequence and TEI numbers, which need to be
+ * replaced in the packet. Either way, give precedence to the proxy, if
+ * configured. */
+
+ if (unmapped_from_seq)
+ *unmapped_from_seq = NULL;
+ if (final_unmapped)
+ *final_unmapped = NULL;
+ p->tun = NULL;
+
+ struct gtphub_peer_port *from_seq = NULL;
+ struct gtphub_peer_port *from_tei = NULL;
+ struct gtphub_peer_port *unmapped = NULL;
+
+ from_seq = gtphub_unmap_seq(p, from);
+
+ if (gtphub_unmap_header_tei(&from_tei, &p->tun, hub, p, from) < 0)
+ return -1;
+
+ struct gtphub_peer *from_peer = from->peer_addr->peer;
+ if (from_seq && from_tei && (from_seq != from_tei)) {
+ LOG(LOGL_DEBUG,
+ "Seq unmap and TEI unmap yield two different peers."
+ " Using seq unmap."
+ " (from %s %s: seq %d yields %s, tei %u yields %s)\n",
+ gtphub_plane_idx_names[p->plane_idx],
+ gtphub_peer_str(from_peer),
+ (int)p->seq,
+ gtphub_port_str(from_seq),
+ (unsigned int)p->header_tei_rx,
+ gtphub_port_str2(from_tei)
+ );
+ }
+ unmapped = (from_seq? from_seq : from_tei);
+
+ if (unmapped && to_proxy && (unmapped != to_proxy)) {
+ LOG(LOGL_NOTICE,
+ "Unmap yields a different peer than the configured proxy."
+ " Using proxy."
+ " unmapped: %s proxy: %s\n",
+ gtphub_port_str(unmapped),
+ gtphub_port_str2(to_proxy)
+ );
+ }
+ unmapped = (to_proxy? to_proxy : unmapped);
+
+ if (!unmapped) {
+ /* Return no error, but returned pointers are all NULL. */
+ return 0;
+ }
+
+ if (unmapped_from_seq)
+ *unmapped_from_seq = from_seq;
+ if (final_unmapped)
+ *final_unmapped = unmapped;
+ return 0;
+}
+
+static int gsn_addr_to_sockaddr(struct gsn_addr *src,
+ uint16_t port,
+ struct osmo_sockaddr *dst)
+{
+ return osmo_sockaddr_init_udp(dst, gsn_addr_to_str(src), port);
+}
+
+/* If p is an Echo request, replace p's data with the matching response and
+ * return 1. If p is no Echo request, return 0, or -1 if an invalid packet is
+ * detected. */
+static int gtphub_handle_echo_req(struct gtphub *hub, struct gtp_packet_desc *p,
+ uint8_t **reply_buf)
+{
+ if (p->type != GTP_ECHO_REQ)
+ return 0;
+
+ static uint8_t echo_response_data[14] = {
+ 0x32, /* GTP v1 flags */
+ GTP_ECHO_RSP,
+ 0x00, 14 - 8, /* Length in network byte order */
+ 0x00, 0x00, 0x00, 0x00, /* Zero TEI */
+ 0, 0, /* Seq, to be replaced */
+ 0, 0, /* no extensions */
+ 0x0e, /* Recovery IE */
+ 0 /* Restart counter, to be replaced */
+ };
+ uint16_t *seq = (uint16_t*)&echo_response_data[8];
+ uint8_t *recovery = &echo_response_data[13];
+
+ *seq = hton16(p->seq);
+ *recovery = hub->restart_counter;
+
+ *reply_buf = echo_response_data;
+
+ return sizeof(echo_response_data);
+}
+
+struct gtphub_peer_port *gtphub_known_addr_have_port(const struct gtphub_bind *bind,
+ const struct osmo_sockaddr *addr);
+
+/* Parse buffer as GTP packet, replace elements in-place and return the ofd and
+ * address to forward to. Return a pointer to the osmo_fd, but copy the
+ * sockaddr to *to_addr. The reason for this is that the sockaddr may expire at
+ * any moment, while the osmo_fd is guaranteed to persist. Return the number of
+ * bytes to forward, 0 or less on failure. */
+int gtphub_handle_buf(struct gtphub *hub,
+ unsigned int side_idx,
+ unsigned int plane_idx,
+ const struct osmo_sockaddr *from_addr,
+ uint8_t *buf,
+ size_t received,
+ time_t now,
+ uint8_t **reply_buf,
+ struct osmo_fd **to_ofd,
+ struct osmo_sockaddr *to_addr)
+{
+ struct gtphub_bind *from_bind = &hub->to_gsns[side_idx][plane_idx];
+ struct gtphub_bind *to_bind = &hub->to_gsns[other_side_idx(side_idx)][plane_idx];
+
+ rate_ctr_add(&from_bind->counters_io->ctr[GTPH_CTR_BYTES_IN],
+ received);
+
+ struct gtp_packet_desc p;
+ gtp_decode(buf, received, side_idx, plane_idx, &p, now);
+
+ LOG(LOGL_DEBUG, "%s rx %s from %s %s%s\n",
+ (side_idx == GTPH_SIDE_GGSN)? "<-" : "->",
+ gtphub_plane_idx_names[plane_idx],
+ gtphub_side_idx_names[side_idx],
+ osmo_sockaddr_to_str(from_addr),
+ gtp_type_str(p.type));
+
+ if (p.rc <= 0) {
+ LOG(LOGL_ERROR, "INVALID: dropping GTP packet%s from %s %s %s\n",
+ gtp_type_str(p.type),
+ gtphub_side_idx_names[side_idx],
+ gtphub_plane_idx_names[plane_idx],
+ osmo_sockaddr_to_str(from_addr));
+ return -1;
+ }
+
+ rate_ctr_inc(&from_bind->counters_io->ctr[GTPH_CTR_PKTS_IN]);
+
+ int reply_len;
+ reply_len = gtphub_handle_echo_req(hub, &p, reply_buf);
+ if (reply_len > 0) {
+ /* It was an echo. Nothing left to do. */
+ osmo_sockaddr_copy(to_addr, from_addr);
+ *to_ofd = &from_bind->ofd;
+
+ rate_ctr_inc(&from_bind->counters_io->ctr[GTPH_CTR_PKTS_OUT]);
+ rate_ctr_add(&from_bind->counters_io->ctr[GTPH_CTR_BYTES_OUT],
+ reply_len);
+ LOG(LOGL_DEBUG, "%s Echo response to %s: %d bytes to %s\n",
+ (side_idx == GTPH_SIDE_GGSN)? "-->" : "<--",
+ gtphub_side_idx_names[side_idx],
+ (int)reply_len, osmo_sockaddr_to_str(to_addr));
+ return reply_len;
+ }
+ if (reply_len < 0)
+ return -1;
+
+ *to_ofd = &to_bind->ofd;
+
+ /* If a proxy is configured, check that it's indeed that proxy talking
+ * to us. A proxy is a forced 1:1 connection, e.g. to another gtphub,
+ * so no-one else is allowed to talk to us from that side. */
+ struct gtphub_peer_port *from_peer = hub->proxy[side_idx][plane_idx];
+ if (from_peer) {
+ if (osmo_sockaddr_cmp(&from_peer->sa, from_addr) != 0) {
+ LOG(LOGL_ERROR,
+ "Rejecting: %s proxy configured, but GTP packet"
+ " received on %s bind is from another sender:"
+ " proxy: %s sender: %s\n",
+ gtphub_side_idx_names[side_idx],
+ gtphub_side_idx_names[side_idx],
+ gtphub_port_str(from_peer),
+ osmo_sockaddr_to_str(from_addr));
+ return -1;
+ }
+ }
+
+ if (!from_peer) {
+ /* Find or create a peer with a matching address. The sender's
+ * port may in fact differ. */
+ from_peer = gtphub_known_addr_have_port(from_bind, from_addr);
+ }
+
+ /* If any PDP context has been created, we already have an entry for
+ * this GSN. If we don't have an entry, a GGSN has nothing to tell us
+ * about, while an SGSN may initiate a PDP context. */
+ if (!from_peer) {
+ if (side_idx == GTPH_SIDE_GGSN) {
+ LOG(LOGL_ERROR, "Dropping packet%s: unknown GGSN peer: %s\n",
+ gtp_type_str(p.type),
+ osmo_sockaddr_to_str(from_addr));
+ return -1;
+ } else {
+ /* SGSN */
+ /* A new peer. If this is on the Ctrl plane, an SGSN
+ * may make first contact without being known yet, so
+ * create the peer struct for the current sender. */
+ if (plane_idx != GTPH_PLANE_CTRL) {
+ LOG(LOGL_ERROR,
+ "Dropping packet%s: User plane peer was not"
+ "announced by PDP Context: %s\n",
+ gtp_type_str(p.type),
+ osmo_sockaddr_to_str(from_addr));
+ return -1;
+ }
+
+ struct gsn_addr from_gsna;
+ uint16_t from_port;
+ if (gsn_addr_from_sockaddr(&from_gsna, &from_port, from_addr) != 0)
+ return -1;
+
+ from_peer = gtphub_port_have(hub, from_bind, &from_gsna, from_port);
+ }
+ }
+
+ if (!from_peer) {
+ /* This could theoretically happen for invalid address data or
+ * somesuch. */
+ LOG(LOGL_ERROR, "Dropping packet%s: invalid %s peer: %s\n",
+ gtp_type_str(p.type),
+ gtphub_side_idx_names[side_idx],
+ osmo_sockaddr_to_str(from_addr));
+ return -1;
+ }
+
+ rate_ctr_add(&from_peer->counters_io->ctr[GTPH_CTR_BYTES_IN],
+ received);
+ rate_ctr_inc(&from_peer->counters_io->ctr[GTPH_CTR_PKTS_IN]);
+
+ LOG(LOGL_DEBUG, "from %s peer: %s\n", gtphub_side_idx_names[side_idx],
+ gtphub_port_str(from_peer));
+
+ gtphub_check_restart_counter(hub, &p, from_peer);
+ gtphub_map_restart_counter(hub, &p);
+
+ struct gtphub_peer_port *to_peer_from_seq;
+ struct gtphub_peer_port *to_peer;
+ if (gtphub_unmap(hub, &p, from_peer,
+ hub->proxy[other_side_idx(side_idx)][plane_idx],
+ &to_peer, &to_peer_from_seq)
+ != 0) {
+ return -1;
+ }
+
+ if (p.tun) {
+ struct gtphub_tunnel_endpoint *te = &p.tun->endpoint[p.side_idx][p.plane_idx];
+ rate_ctr_add(&te->counters_io->ctr[GTPH_CTR_BYTES_IN],
+ received);
+ rate_ctr_inc(&te->counters_io->ctr[GTPH_CTR_PKTS_IN]);
+ }
+
+ if ((!to_peer) && (side_idx == GTPH_SIDE_SGSN)) {
+ if (gtphub_resolve_ggsn(hub, &p, &to_peer) < 0)
+ return -1;
+ }
+
+ if (!to_peer && p.tun && p.type == GTP_DELETE_PDP_RSP) {
+ /* It's a delete confirmation for a tunnel that is partly
+ * invalid, probably marked unsuable due to a restarted peer.
+ * Remove the tunnel and be happy without forwarding. */
+ expiring_item_del(&p.tun->expiry_entry);
+ p.tun = NULL;
+ return 0;
+ }
+
+ if (!to_peer) {
+ LOG(LOGL_ERROR, "No %s to send to. Dropping packet%s"
+ " (type=%" PRIu8 ", header-TEI=%" PRIx32 ", seq=%" PRIx16 ").\n",
+ gtphub_side_idx_names[other_side_idx(side_idx)],
+ gtp_type_str(p.type),
+ p.type, p.header_tei_rx, p.seq
+ );
+ return -1;
+ }
+
+ if (plane_idx == GTPH_PLANE_CTRL) {
+ /* This may be a Create PDP Context response. If it is, there
+ * are other addresses in the GTP message to set up apart from
+ * the sender. */
+ if (gtphub_handle_pdp_ctx(hub, &p, from_peer, to_peer)
+ != 0)
+ return -1;
+ }
+
+ /* Either to_peer was resolved from an existing tunnel,
+ * or a PDP Ctx and thus a tunnel has just been created,
+ * or the tunnel has been deleted due to this message. */
+ OSMO_ASSERT(p.tun || (p.type == GTP_DELETE_PDP_RSP));
+
+ /* If the GGSN is replying to an SGSN request, the sequence nr has
+ * already been unmapped above (to_peer_from_seq != NULL), and we need not
+ * create a new mapping. */
+ if (!to_peer_from_seq)
+ gtphub_map_seq(&p, from_peer, to_peer);
+
+ osmo_sockaddr_copy(to_addr, &to_peer->sa);
+
+ *reply_buf = (uint8_t*)p.data;
+
+ if (received) {
+ rate_ctr_inc(&to_bind->counters_io->ctr[GTPH_CTR_PKTS_OUT]);
+ rate_ctr_add(&to_bind->counters_io->ctr[GTPH_CTR_BYTES_OUT],
+ received);
+
+ rate_ctr_inc(&to_peer->counters_io->ctr[GTPH_CTR_PKTS_OUT]);
+ rate_ctr_add(&to_peer->counters_io->ctr[GTPH_CTR_BYTES_OUT],
+ received);
+ }
+
+ if (p.tun) {
+ struct gtphub_tunnel_endpoint *te = &p.tun->endpoint[other_side_idx(p.side_idx)][p.plane_idx];
+ rate_ctr_inc(&te->counters_io->ctr[GTPH_CTR_PKTS_OUT]);
+ rate_ctr_add(&te->counters_io->ctr[GTPH_CTR_BYTES_OUT],
+ received);
+ }
+
+ LOG(LOGL_DEBUG, "%s Forward to %s:"
+ " header-TEI %" PRIx32", seq %" PRIx16", %d bytes to %s\n",
+ (side_idx == GTPH_SIDE_SGSN)? "-->" : "<--",
+ gtphub_side_idx_names[other_side_idx(side_idx)],
+ p.header_tei, p.seq,
+ (int)received, osmo_sockaddr_to_str(to_addr));
+ return received;
+}
+
+static void resolved_gssn_del_cb(struct expiring_item *expi)
+{
+ struct gtphub_resolved_ggsn *ggsn;
+ ggsn = container_of(expi, struct gtphub_resolved_ggsn, expiry_entry);
+
+ gtphub_port_ref_count_dec(ggsn->peer);
+ llist_del(&ggsn->entry);
+
+ ggsn->expiry_entry.del_cb = 0;
+ expiring_item_del(&ggsn->expiry_entry);
+
+ talloc_free(ggsn);
+}
+
+void gtphub_resolved_ggsn(struct gtphub *hub, const char *apn_oi_str,
+ struct gsn_addr *resolved_addr,
+ time_t now)
+{
+ struct gtphub_peer_port *pp;
+ struct gtphub_resolved_ggsn *ggsn;
+
+ LOG(LOGL_DEBUG, "Resolved GGSN callback: %s %s\n",
+ apn_oi_str, osmo_hexdump((unsigned char*)resolved_addr,
+ sizeof(*resolved_addr)));
+
+ pp = gtphub_port_have(hub, &hub->to_gsns[GTPH_SIDE_GGSN][GTPH_PLANE_CTRL],
+ resolved_addr, 2123);
+ if (!pp) {
+ LOG(LOGL_ERROR, "Internal: Cannot create/find peer '%s'\n",
+ gsn_addr_to_str(resolved_addr));
+ return;
+ }
+
+ ggsn = talloc_zero(osmo_gtphub_ctx, struct gtphub_resolved_ggsn);
+ OSMO_ASSERT(ggsn);
+ INIT_LLIST_HEAD(&ggsn->entry);
+ expiring_item_init(&ggsn->expiry_entry);
+
+ ggsn->peer = pp;
+ gtphub_port_ref_count_inc(pp);
+
+ osmo_strlcpy(ggsn->apn_oi_str, apn_oi_str, sizeof(ggsn->apn_oi_str));
+
+ ggsn->expiry_entry.del_cb = resolved_gssn_del_cb;
+ expiry_add(&hub->expire_slowly, &ggsn->expiry_entry, now);
+
+ llist_add(&ggsn->entry, &hub->resolved_ggsns);
+}
+
+static int gtphub_gc_peer_port(struct gtphub_peer_port *pp)
+{
+ return pp->ref_count == 0;
+}
+
+static int gtphub_gc_peer_addr(struct gtphub_peer_addr *pa)
+{
+ struct gtphub_peer_port *pp, *npp;
+ llist_for_each_entry_safe(pp, npp, &pa->ports, entry) {
+ if (gtphub_gc_peer_port(pp)) {
+ LOG(LOGL_DEBUG, "expired: peer %s\n",
+ gtphub_port_str(pp));
+ gtphub_peer_port_del(pp);
+ }
+ }
+ return llist_empty(&pa->ports);
+}
+
+static int gtphub_gc_peer(struct gtphub_peer *p)
+{
+ struct gtphub_peer_addr *pa, *npa;
+ llist_for_each_entry_safe(pa, npa, &p->addresses, entry) {
+ if (gtphub_gc_peer_addr(pa)) {
+ gtphub_peer_addr_del(pa);
+ }
+ }
+
+ /* Note that there's a ref_count in each gtphub_peer_port instance
+ * listed within p->addresses, referenced by TEI mappings from
+ * hub->tei_map. As long as those don't expire, this peer will stay. */
+
+ return llist_empty(&p->addresses)
+ && nr_map_empty(&p->seq_map);
+}
+
+static void gtphub_gc_bind(struct gtphub_bind *b)
+{
+ struct gtphub_peer *p, *n;
+ llist_for_each_entry_safe(p, n, &b->peers, entry) {
+ if (gtphub_gc_peer(p)) {
+ gtphub_peer_del(p);
+ }
+ }
+}
+
+void gtphub_gc(struct gtphub *hub, time_t now)
+{
+ int expired;
+ expired = expiry_tick(&hub->expire_quickly, now);
+ expired += expiry_tick(&hub->expire_slowly, now);
+
+ /* ... */
+
+ if (expired) {
+ int s, p;
+ for_each_side_and_plane(s, p) {
+ gtphub_gc_bind(&hub->to_gsns[s][p]);
+ }
+ }
+}
+
+static void gtphub_gc_cb(void *data)
+{
+ struct gtphub *hub = data;
+ gtphub_gc(hub, gtphub_now());
+ osmo_timer_schedule(&hub->gc_timer, GTPH_GC_TICK_SECONDS, 0);
+}
+
+static void gtphub_gc_start(struct gtphub *hub)
+{
+ osmo_timer_setup(&hub->gc_timer, gtphub_gc_cb, hub);
+ osmo_timer_schedule(&hub->gc_timer, GTPH_GC_TICK_SECONDS, 0);
+}
+
+/* called by unit tests */
+void gtphub_init(struct gtphub *hub)
+{
+ gtphub_zero(hub);
+
+ INIT_LLIST_HEAD(&hub->tunnels);
+ INIT_LLIST_HEAD(&hub->pending_deletes);
+
+ expiry_init(&hub->expire_quickly, GTPH_EXPIRE_QUICKLY_SECS);
+ expiry_init(&hub->expire_slowly, GTPH_EXPIRE_SLOWLY_MINUTES * 60);
+
+ nr_pool_init(&hub->tei_pool, 1, 0xffffffff);
+
+ int side_idx;
+ int plane_idx;
+ for_each_side_and_plane(side_idx, plane_idx) {
+ gtphub_bind_init(&hub->to_gsns[side_idx][plane_idx], CTR_IDX_HUB(side_idx, plane_idx));
+ }
+
+ hub->to_gsns[GTPH_SIDE_SGSN][GTPH_PLANE_CTRL].label = "SGSN Ctrl";
+ hub->to_gsns[GTPH_SIDE_GGSN][GTPH_PLANE_CTRL].label = "GGSN Ctrl";
+ hub->to_gsns[GTPH_SIDE_SGSN][GTPH_PLANE_USER].label = "SGSN User";
+ hub->to_gsns[GTPH_SIDE_GGSN][GTPH_PLANE_USER].label = "GGSN User";
+}
+
+/* For the test suite, this is kept separate from gtphub_stop(), which also
+ * closes sockets. The test suite avoids using sockets and would cause
+ * segfaults when trying to close uninitialized ofds. */
+void gtphub_free(struct gtphub *hub)
+{
+ /* By expiring all mappings, a garbage collection should free
+ * everything else. A gtphub_bind_free() will assert that everything is
+ * indeed empty. */
+ expiry_clear(&hub->expire_quickly);
+ expiry_clear(&hub->expire_slowly);
+
+ int side_idx;
+ int plane_idx;
+ for_each_side_and_plane(side_idx, plane_idx) {
+ gtphub_gc_bind(&hub->to_gsns[side_idx][plane_idx]);
+ gtphub_bind_free(&hub->to_gsns[side_idx][plane_idx]);
+ }
+}
+
+void gtphub_stop(struct gtphub *hub)
+{
+ int side_idx;
+ int plane_idx;
+ for_each_side_and_plane(side_idx, plane_idx) {
+ gtphub_bind_stop(&hub->to_gsns[side_idx][plane_idx]);
+ }
+ gtphub_free(hub);
+}
+
+static int gtphub_make_proxy(struct gtphub *hub,
+ struct gtphub_peer_port **pp,
+ struct gtphub_bind *bind,
+ const struct gtphub_cfg_addr *addr)
+{
+ if (!addr->addr_str)
+ return 0;
+
+ struct gsn_addr gsna;
+ if (gsn_addr_from_str(&gsna, addr->addr_str) != 0)
+ return -1;
+
+ *pp = gtphub_port_have(hub, bind, &gsna, addr->port);
+
+ /* This is *the* proxy. Make sure it is never expired. */
+ gtphub_port_ref_count_inc(*pp);
+ return 0;
+}
+
+int gtphub_start(struct gtphub *hub, struct gtphub_cfg *cfg,
+ uint8_t restart_counter)
+{
+ gtphub_init(hub);
+
+ hub->restart_counter = restart_counter;
+ hub->sgsn_use_sender = cfg->sgsn_use_sender? 1 : 0;
+
+ /* If a Ctrl plane proxy is configured, ares will never be used. */
+ if (!cfg->proxy[GTPH_SIDE_GGSN][GTPH_PLANE_CTRL].addr_str) {
+ if (gtphub_ares_init(hub) != 0) {
+ LOG(LOGL_FATAL, "Failed to initialize ares\n");
+ return -1;
+ }
+ }
+
+ int side_idx;
+ int plane_idx;
+ for_each_side_and_plane(side_idx, plane_idx) {
+ int rc;
+ rc = gtphub_bind_start(&hub->to_gsns[side_idx][plane_idx],
+ &cfg->to_gsns[side_idx][plane_idx],
+ (side_idx == GTPH_SIDE_SGSN)
+ ? from_sgsns_read_cb
+ : from_ggsns_read_cb,
+ hub, plane_idx);
+ if (rc) {
+ LOG(LOGL_FATAL, "Failed to bind for %ss (%s)\n",
+ gtphub_side_idx_names[side_idx],
+ gtphub_plane_idx_names[plane_idx]);
+ return rc;
+ }
+ }
+
+ for_each_side_and_plane(side_idx, plane_idx) {
+ if (gtphub_make_proxy(hub,
+ &hub->proxy[side_idx][plane_idx],
+ &hub->to_gsns[side_idx][plane_idx],
+ &cfg->proxy[side_idx][plane_idx])
+ != 0) {
+ LOG(LOGL_FATAL, "Cannot configure %s proxy"
+ " %s port %d.\n",
+ gtphub_side_idx_names[side_idx],
+ cfg->proxy[side_idx][plane_idx].addr_str,
+ (int)cfg->proxy[side_idx][plane_idx].port);
+ return -1;
+ }
+ }
+
+ for_each_side_and_plane(side_idx, plane_idx) {
+ if (hub->proxy[side_idx][plane_idx])
+ LOG(LOGL_NOTICE, "Using %s %s proxy %s\n",
+ gtphub_side_idx_names[side_idx],
+ gtphub_plane_idx_names[plane_idx],
+ gtphub_port_str(hub->proxy[side_idx][plane_idx]));
+ }
+
+ if (hub->sgsn_use_sender)
+ LOG(LOGL_NOTICE, "Using sender address and port for SGSN instead of GSN Addr IE and default ports.\n");
+
+ gtphub_gc_start(hub);
+ return 0;
+}
+
+static struct gtphub_peer_addr *gtphub_peer_find_addr(const struct gtphub_peer *peer,
+ const struct gsn_addr *addr)
+{
+ struct gtphub_peer_addr *a;
+ llist_for_each_entry(a, &peer->addresses, entry) {
+ if (gsn_addr_same(&a->addr, addr))
+ return a;
+ }
+ return NULL;
+}
+
+static struct gtphub_peer_port *gtphub_addr_find_port(const struct gtphub_peer_addr *a,
+ uint16_t port)
+{
+ OSMO_ASSERT(port);
+ struct gtphub_peer_port *pp;
+ llist_for_each_entry(pp, &a->ports, entry) {
+ if (pp->port == port)
+ return pp;
+ }
+ return NULL;
+}
+
+static struct gtphub_peer_addr *gtphub_addr_find(const struct gtphub_bind *bind,
+ const struct gsn_addr *addr)
+{
+ struct gtphub_peer *peer;
+ llist_for_each_entry(peer, &bind->peers, entry) {
+ struct gtphub_peer_addr *a = gtphub_peer_find_addr(peer, addr);
+ if (a)
+ return a;
+ }
+ return NULL;
+}
+
+static struct gtphub_peer_port *gtphub_port_find(const struct gtphub_bind *bind,
+ const struct gsn_addr *addr,
+ uint16_t port)
+{
+ struct gtphub_peer_addr *a = gtphub_addr_find(bind, addr);
+ if (!a)
+ return NULL;
+ return gtphub_addr_find_port(a, port);
+}
+
+struct gtphub_peer_port *gtphub_port_find_sa(const struct gtphub_bind *bind,
+ const struct osmo_sockaddr *addr)
+{
+ struct gsn_addr gsna;
+ uint16_t port;
+ if (gsn_addr_from_sockaddr(&gsna, &port, addr) != 0)
+ return NULL;
+
+ return gtphub_port_find(bind, &gsna, port);
+}
+
+static struct gtphub_peer *gtphub_peer_new(struct gtphub *hub,
+ struct gtphub_bind *bind)
+{
+ struct gtphub_peer *peer = talloc_zero(osmo_gtphub_ctx,
+ struct gtphub_peer);
+ OSMO_ASSERT(peer);
+
+ INIT_LLIST_HEAD(&peer->addresses);
+
+ nr_pool_init(&peer->seq_pool, 0, 0xffff);
+ nr_map_init(&peer->seq_map, &peer->seq_pool, &hub->expire_quickly);
+
+ /* TODO use something random to pick the initial sequence nr.
+ 0x6d31 produces the ASCII character sequence 'm1', currently used in
+ gtphub_nc_test.sh. */
+ peer->seq_pool.last_nr = 0x6d31 - 1;
+
+ llist_add(&peer->entry, &bind->peers);
+ return peer;
+}
+
+static struct gtphub_peer_addr *gtphub_peer_add_addr(struct gtphub_peer *peer,
+ const struct gsn_addr *addr)
+{
+ struct gtphub_peer_addr *a;
+ a = talloc_zero(osmo_gtphub_ctx, struct gtphub_peer_addr);
+ OSMO_ASSERT(a);
+ a->peer = peer;
+ gsn_addr_copy(&a->addr, addr);
+ INIT_LLIST_HEAD(&a->ports);
+ llist_add(&a->entry, &peer->addresses);
+
+ return a;
+}
+
+static struct gtphub_peer_addr *gtphub_addr_have(struct gtphub *hub,
+ struct gtphub_bind *bind,
+ const struct gsn_addr *addr)
+{
+ struct gtphub_peer_addr *a = gtphub_addr_find(bind, addr);
+ if (a)
+ return a;
+
+ /* If we haven't found an address, that means we need to create an
+ * entirely new peer for the new address. More addresses may be added
+ * to this peer later, but not via this function. */
+ struct gtphub_peer *peer = gtphub_peer_new(hub, bind);
+
+ a = gtphub_peer_add_addr(peer, addr);
+
+ LOG(LOGL_DEBUG, "New peer address: %s %s\n",
+ bind->label,
+ gsn_addr_to_str(&a->addr));
+
+ return a;
+}
+
+static struct gtphub_peer_port *gtphub_addr_add_port(struct gtphub_peer_addr *a,
+ uint16_t port)
+{
+ struct gtphub_peer_port *pp;
+
+ pp = talloc_zero(osmo_gtphub_ctx, struct gtphub_peer_port);
+ OSMO_ASSERT(pp);
+ pp->peer_addr = a;
+ pp->port = port;
+ pp->last_restart_count = -1;
+
+ if (gsn_addr_to_sockaddr(&a->addr, port, &pp->sa) != 0) {
+ talloc_free(pp);
+ return NULL;
+ }
+
+ pp->counters_io = rate_ctr_group_alloc(osmo_gtphub_ctx,
+ &gtphub_ctrg_io_desc, port);
+ if (!pp->counters_io) {
+ LOG(LOGL_ERROR, "Failed to allocate rate counters for %s:%u\n", gsn_addr_to_str(&a->addr), port);
+ talloc_free(pp);
+ return NULL;
+ }
+
+ llist_add(&pp->entry, &a->ports);
+
+ LOG(LOGL_DEBUG, "New peer port: %s port %d\n",
+ gsn_addr_to_str(&a->addr),
+ (int)port);
+
+ return pp;
+}
+
+struct gtphub_peer_port *gtphub_port_have(struct gtphub *hub,
+ struct gtphub_bind *bind,
+ const struct gsn_addr *addr,
+ uint16_t port)
+{
+ struct gtphub_peer_addr *a = gtphub_addr_have(hub, bind, addr);
+
+ struct gtphub_peer_port *pp = gtphub_addr_find_port(a, port);
+ if (pp)
+ return pp;
+
+ return gtphub_addr_add_port(a, port);
+}
+
+/* Find a GGSN peer with a matching address. If the address is known but the
+ * port not, create a new port for that peer address. */
+struct gtphub_peer_port *gtphub_known_addr_have_port(const struct gtphub_bind *bind,
+ const struct osmo_sockaddr *addr)
+{
+ struct gtphub_peer_addr *pa;
+ struct gtphub_peer_port *pp;
+
+ struct gsn_addr gsna;
+ uint16_t port;
+ int rc = gsn_addr_from_sockaddr(&gsna, &port, addr);
+ if (rc < 0)
+ LOG(LOGL_ERROR, "%s(): failed to obtain GSN address\n", __func__);
+
+ pa = gtphub_addr_find(bind, &gsna);
+ if (!pa)
+ return NULL;
+
+ pp = gtphub_addr_find_port(pa, port);
+
+ if (!pp)
+ pp = gtphub_addr_add_port(pa, port);
+
+ return pp;
+}
+
+
+/* Return 0 if the message in p is not applicable for GGSN resolution, -1 if
+ * resolution should be possible but failed, and 1 if resolution was
+ * successful. *pp will be set to NULL if <1 is returned. */
+static int gtphub_resolve_ggsn(struct gtphub *hub,
+ struct gtp_packet_desc *p,
+ struct gtphub_peer_port **pp)
+{
+ *pp = NULL;
+
+ /* TODO determine from message type whether IEs should be present? */
+
+ int rc;
+ const char *imsi_str;
+ rc = get_ie_imsi_str(p->ie, 0, &imsi_str);
+ if (rc < 1)
+ return rc;
+ OSMO_ASSERT(imsi_str);
+
+ const char *apn_str;
+ rc = get_ie_apn_str(p->ie, &apn_str);
+ if (rc < 1)
+ return rc;
+ OSMO_ASSERT(apn_str);
+
+ *pp = gtphub_resolve_ggsn_addr(hub, imsi_str, apn_str);
+ return (*pp)? 1 : -1;
+}
+
+
+/* TODO move to osmocom/core/socket.c ? */
+/* use this in osmo_sock_init() to remove dup. */
+/* Internal: call getaddrinfo for osmo_sockaddr_init(). The caller is required
+ to call freeaddrinfo(*result), iff zero is returned. */
+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 ? */
+int osmo_sockaddr_init(struct osmo_sockaddr *addr,
+ 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) {
+ LOG(LOGL_ERROR, "getaddrinfo returned error %d\n", (int)rc);
+ return -EINVAL;
+ }
+
+ OSMO_ASSERT(res->ai_addrlen <= sizeof(addr->a));
+ memcpy(&addr->a, res->ai_addr, res->ai_addrlen);
+ addr->l = res->ai_addrlen;
+ freeaddrinfo(res);
+
+ return 0;
+}
+
+int osmo_sockaddr_to_strs(char *addr_str, size_t addr_str_len,
+ char *port_str, size_t port_str_len,
+ const struct osmo_sockaddr *addr,
+ int flags)
+{
+ int rc;
+
+ if ((addr->l < 1) || (addr->l > sizeof(addr->a))) {
+ LOGP(DGTPHUB, LOGL_ERROR, "Invalid address size: %d\n", addr->l);
+ return -1;
+ }
+
+ if (addr->l > sizeof(addr->a)) {
+ LOGP(DGTPHUB, LOGL_ERROR, "Invalid address: too long: %d\n",
+ addr->l);
+ return -1;
+ }
+
+ rc = getnameinfo((struct sockaddr*)&addr->a, addr->l,
+ addr_str, addr_str_len,
+ port_str, port_str_len,
+ flags);
+
+ if (rc)
+ LOGP(DGTPHUB, LOGL_ERROR, "Invalid address: %s: %s\n",
+ gai_strerror(rc), osmo_hexdump((uint8_t*)&addr->a,
+ addr->l));
+
+ return rc;
+}
+
+const char *osmo_sockaddr_to_strb(const struct osmo_sockaddr *addr,
+ char *buf, size_t buf_len)
+{
+ const int portbuf_len = 6;
+ OSMO_ASSERT(buf_len > portbuf_len);
+ char *portbuf = buf + buf_len - portbuf_len;
+ buf_len -= portbuf_len;
+ if (osmo_sockaddr_to_strs(buf, buf_len,
+ portbuf, portbuf_len,
+ addr,
+ NI_NUMERICHOST | NI_NUMERICSERV))
+ return NULL;
+
+ char *pos = buf + strnlen(buf, buf_len-1);
+ size_t len = buf_len - (pos - buf);
+
+ snprintf(pos, len, " port %s", portbuf);
+ buf[buf_len-1] = '\0';
+
+ return buf;
+}
+
+const char *osmo_sockaddr_to_str(const struct osmo_sockaddr *addr)
+{
+ static char buf[256];
+ const char *result = osmo_sockaddr_to_strb(addr, buf, sizeof(buf));
+ if (! result)
+ return "(invalid)";
+ return result;
+}
+
+int osmo_sockaddr_cmp(const struct osmo_sockaddr *a,
+ const struct osmo_sockaddr *b)
+{
+ if (a == b)
+ return 0;
+ if (!a)
+ return -1;
+ if (!b)
+ return 1;
+ if (a->l != b->l) {
+ /* Lengths are not the same, but determine the order. Will
+ * anyone ever sort a list by osmo_sockaddr though...? */
+ int cmp = memcmp(&a->a, &b->a, (a->l < b->l)? a->l : b->l);
+ if (cmp == 0) {
+ if (a->l < b->l)
+ return -1;
+ else
+ return 1;
+ }
+ return cmp;
+ }
+ return memcmp(&a->a, &b->a, a->l);
+}
+
+void osmo_sockaddr_copy(struct osmo_sockaddr *dst,
+ const struct osmo_sockaddr *src)
+{
+ OSMO_ASSERT(src->l <= sizeof(dst->a));
+ memcpy(&dst->a, &src->a, src->l);
+ dst->l = src->l;
+}