mtp: Allow to run multiple links through the same socket
The UDP socket will be shared between multiple links, the
snmp session will be also shared between multiple links on
the same hardware.
diff --git a/include/bsc_data.h b/include/bsc_data.h
index 758932f..587afec 100644
--- a/include/bsc_data.h
+++ b/include/bsc_data.h
@@ -40,19 +40,27 @@
struct bsc_data;
struct snmp_mtp_session;
+struct mtp_udp_data {
+ struct write_queue write_queue;
+ struct snmp_mtp_session *session;
+
+ struct llist_head links;
+};
+
struct mtp_udp_link {
/* subclass */
struct mtp_link base;
/* UDP specific stuff */
struct bsc_data *bsc;
- struct write_queue write_queue;
- struct sockaddr_in remote;
- struct snmp_mtp_session *session;
int link_index;
int reset_timeout;
-};
+ struct sockaddr_in remote;
+
+ struct mtp_udp_data *data;
+ struct llist_head entry;
+};
struct bsc_data {
/* MSC */
@@ -88,6 +96,9 @@
/* mgcp messgaes */
struct write_queue mgcp_agent;
+ /* udp code */
+ struct mtp_udp_data udp_data;
+
int dpc;
int opc;
int sccp_opc;
@@ -129,7 +140,8 @@
unsigned int sls_for_src_ref(struct sccp_source_reference *ref);
/* udp init */
-int link_udp_init(struct mtp_udp_link *data, int src_port, const char *dest_ip, int port);
+int link_global_init(struct mtp_udp_data *data, int src_port);
+int link_udp_init(struct mtp_udp_link *data, const char *dest_ip, int port);
int link_init(struct bsc_data *bsc);
int link_shutdown_all(struct mtp_link_set *);
int link_reset_all(struct mtp_link_set *);
diff --git a/src/link_udp.c b/src/link_udp.c
index 7e0b94b..04dcec8 100644
--- a/src/link_udp.c
+++ b/src/link_udp.c
@@ -35,12 +35,30 @@
#include <string.h>
#include <unistd.h>
+static struct mtp_udp_link *find_link(struct mtp_udp_data *data, uint16_t link_index)
+{
+ struct mtp_udp_link *lnk;
+
+ llist_for_each_entry(lnk, &data->links, entry)
+ if (lnk->link_index == link_index)
+ return lnk;
+
+ return NULL;
+}
+
+
static int udp_write_cb(struct bsc_fd *fd, struct msgb *msg)
{
+ struct mtp_udp_data *data;
struct mtp_udp_link *link;
int rc;
- link = fd->data;
+ data = fd->data;
+ link = find_link(data, msg->cb[0]);
+ if (!link) {
+ LOGP(DINP, LOGL_ERROR, "Failed to find link with %lu\n", msg->cb[0]);
+ return -1;
+ }
LOGP(DINP, LOGL_DEBUG, "Sending MSU: %s\n", hexdump(msg->data, msg->len));
if (link->base.pcap_fd >= 0)
@@ -59,6 +77,7 @@
static int udp_read_cb(struct bsc_fd *fd)
{
+ struct mtp_udp_data *data;
struct mtp_link *link;
struct udp_data_hdr *hdr;
struct msgb *msg;
@@ -72,7 +91,7 @@
}
- link = (struct mtp_link *) fd->data;
+ data = (struct mtp_udp_data *) fd->data;
rc = read(fd->fd, msg->data, 2096);
if (rc < sizeof(*hdr)) {
LOGP(DINP, LOGL_ERROR, "Failed to read at least size of the header: %d\n", rc);
@@ -80,6 +99,16 @@
goto exit;
}
+ hdr = (struct udp_data_hdr *) msgb_put(msg, sizeof(*hdr));
+ link = (struct mtp_link *) find_link(data, ntohs(hdr->data_link_index));
+
+ if (!link) {
+ LOGP(DINP, LOGL_ERROR, "No link registered for %d\n",
+ ntohs(hdr->data_link_index));
+ goto exit;
+ }
+
+
/* throw away data as the link is down */
if (link->set->available == 0) {
LOGP(DINP, LOGL_ERROR, "The link is down. Not forwarding.\n");
@@ -87,8 +116,6 @@
goto exit;
}
- hdr = (struct udp_data_hdr *) msgb_put(msg, sizeof(*hdr));
-
if (hdr->data_type == UDP_DATA_RETR_COMPL || hdr->data_type == UDP_DATA_RETR_IMPOS) {
LOGP(DINP, LOGL_ERROR, "Link retrieval done. Restarting the link.\n");
mtp_link_failure(link);
@@ -129,7 +156,7 @@
{
struct mtp_udp_link *link = (struct mtp_udp_link *) _data;
- snmp_mtp_activate(link->session, link->link_index);
+ snmp_mtp_activate(link->data->session, link->link_index);
mtp_link_up(&link->base);
}
@@ -142,7 +169,7 @@
LOGP(DINP, LOGL_NOTICE, "Will restart SLTM transmission in %d seconds.\n",
ulnk->reset_timeout);
- snmp_mtp_deactivate(ulnk->session, ulnk->link_index);
+ snmp_mtp_deactivate(ulnk->data->session, ulnk->link_index);
mtp_link_down(link);
/* restart the link in 90 seconds... to force a timeout on the BSC */
@@ -166,7 +193,9 @@
hdr->user_context = 0;
hdr->data_length = htonl(msgb_l2len(msg));
- if (write_queue_enqueue(&ulnk->write_queue, msg) != 0) {
+ msg->cb[0] = ulnk->link_index;
+
+ if (write_queue_enqueue(&ulnk->data->write_queue, msg) != 0) {
LOGP(DINP, LOGL_ERROR, "Failed to enqueue msg.\n");
msgb_free(msg);
return -1;
@@ -182,14 +211,8 @@
return 0;
}
-int link_udp_init(struct mtp_udp_link *link, int src_port, const char *remote, int remote_port)
+int link_udp_init(struct mtp_udp_link *link, const char *remote, int port)
{
- struct sockaddr_in addr;
- int fd;
- int on;
-
- write_queue_init(&link->write_queue, 100);
-
/* function table */
link->base.shutdown = udp_link_dummy;
link->base.clear_queue = udp_link_dummy;
@@ -198,13 +221,33 @@
link->base.start = udp_link_start;
link->base.write = udp_link_write;
- /* socket creation */
- link->write_queue.bfd.data = link;
- link->write_queue.bfd.when = BSC_FD_READ;
- link->write_queue.read_cb = udp_read_cb;
- link->write_queue.write_cb = udp_write_cb;
+ /* prepare the remote */
+ memset(&link->remote, 0, sizeof(link->remote));
+ link->remote.sin_family = AF_INET;
+ link->remote.sin_port = htons(port);
+ inet_aton(remote, &link->remote.sin_addr);
- link->write_queue.bfd.fd = fd = socket(AF_INET, SOCK_DGRAM, 0);
+ /* add it to the list of udp connections */
+ llist_add(&link->entry, &link->data->links);
+ return 0;
+}
+
+int link_global_init(struct mtp_udp_data *data, int src_port)
+{
+ struct sockaddr_in addr;
+ int fd;
+ int on;
+
+ INIT_LLIST_HEAD(&data->links);
+ write_queue_init(&data->write_queue, 100);
+
+ /* socket creation */
+ data->write_queue.bfd.data = data;
+ data->write_queue.bfd.when = BSC_FD_READ;
+ data->write_queue.read_cb = udp_read_cb;
+ data->write_queue.write_cb = udp_write_cb;
+
+ data->write_queue.bfd.fd = fd = socket(AF_INET, SOCK_DGRAM, 0);
if (fd < 0) {
LOGP(DINP, LOGL_ERROR, "Failed to create UDP socket.\n");
return -1;
@@ -225,12 +268,7 @@
}
/* now connect the socket to the remote */
- memset(&link->remote, 0, sizeof(link->remote));
- link->remote.sin_family = AF_INET;
- link->remote.sin_port = htons(remote_port);
- inet_aton(remote, &link->remote.sin_addr);
-
- if (bsc_register_fd(&link->write_queue.bfd) != 0) {
+ if (bsc_register_fd(&data->write_queue.bfd) != 0) {
LOGP(DINP, LOGL_ERROR, "Failed to register BFD.\n");
close(fd);
return -1;
diff --git a/src/links.c b/src/links.c
index 6374afd..bf282b6 100644
--- a/src/links.c
+++ b/src/links.c
@@ -114,6 +114,7 @@
lnk = talloc_zero(bsc->link_set, struct mtp_udp_link);
lnk->base.pcap_fd = bsc->pcap_fd;
lnk->bsc = bsc;
+ lnk->data = &bsc->udp_data;
lnk->link_index = 1;
lnk->reset_timeout = bsc->udp_reset_timeout;
mtp_link_set_add_link(bsc->link_set, (struct mtp_link *) lnk);
@@ -126,12 +127,15 @@
LOGP(DINP, LOGL_NOTICE, "Using UDP MTP mode.\n");
/* setup SNMP first, it is blocking */
- lnk->session = snmp_mtp_session_create(bsc->udp_ip);
- if (!lnk->session)
+ bsc->udp_data.session = snmp_mtp_session_create(bsc->udp_ip);
+ if (!bsc->udp_data.session)
+ return -1;
+
+ if (link_global_init(&bsc->udp_data, bsc->src_port) != 0)
return -1;
/* now connect to the transport */
- if (link_udp_init(lnk, bsc->src_port, bsc->udp_ip, bsc->udp_port) != 0)
+ if (link_udp_init(lnk, bsc->udp_ip, bsc->udp_port) != 0)
return -1;
/*
@@ -140,7 +144,7 @@
* SLTM and it begins a reset. Then we will take it up
* again and do the usual business.
*/
- snmp_mtp_deactivate(lnk->session,
+ snmp_mtp_deactivate(lnk->data->session,
lnk->link_index);
bsc->start_timer.cb = start_rest;
bsc->start_timer.data = &bsc;