input: ipaccess: add preliminary BTS-side for A-bis over IP
This patch adds the BTS-side for the ip.access driver for
A-bis over IP communications.
This patch adds one example under test/ so you can test the
existing BSC and BTS sides over ip.access.
Still incomplete, it requires to allow to register some
callback in the BTS side to perform some action once we
receive some message. This will come in next updates.
diff --git a/src/input/Makefile.am b/src/input/Makefile.am
index 8e9e336..c382269 100644
--- a/src/input/Makefile.am
+++ b/src/input/Makefile.am
@@ -6,6 +6,7 @@
libosmoabis_input_la_SOURCES = dahdi.c \
hsl.c \
+ ipa.c \
ipaccess.c \
lapd.c \
misdn.c
diff --git a/src/input/ipa.c b/src/input/ipa.c
new file mode 100644
index 0000000..6f9639f
--- /dev/null
+++ b/src/input/ipa.c
@@ -0,0 +1,234 @@
+#include "internal.h"
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+#include <sys/fcntl.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+
+#include <osmocom/core/select.h>
+#include <osmocom/gsm/tlv.h>
+#include <osmocom/core/msgb.h>
+#include <osmocom/core/logging.h>
+#include <talloc.h>
+#include <osmocom/abis/e1_input.h>
+#include <osmocom/abis/ipaccess.h>
+#include <osmocom/core/socket.h>
+#include <osmocom/abis/logging.h>
+
+#include <osmocom/abis/ipa.h>
+
+#define IPA_ALLOC_SIZE 1200
+
+static struct msgb *ipa_msg_alloc(void)
+{
+ return msgb_alloc(IPA_ALLOC_SIZE, "Abis/IP");
+}
+
+int ipa_msg_recv(int fd, struct msgb **rmsg)
+{
+ struct msgb *msg;
+ struct ipaccess_head *hh;
+ int len, ret;
+
+ msg = ipa_msg_alloc();
+ if (msg == NULL)
+ return -ENOMEM;
+
+ /* first read our 3-byte header */
+ hh = (struct ipaccess_head *) msg->data;
+ ret = recv(fd, msg->data, sizeof(*hh), 0);
+ if (ret <= 0) {
+ msgb_free(msg);
+ return ret;
+ } else if (ret != sizeof(*hh)) {
+ msgb_free(msg);
+ return -EIO;
+ }
+ msgb_put(msg, ret);
+
+ /* then read the length as specified in header */
+ msg->l2h = msg->data + sizeof(*hh);
+ len = ntohs(hh->len);
+
+ if (len < 0 || IPA_ALLOC_SIZE < len + sizeof(*hh)) {
+ msgb_free(msg);
+ return -EIO;
+ }
+
+ ret = recv(fd, msg->l2h, len, 0);
+ if (ret <= 0) {
+ msgb_free(msg);
+ return ret;
+ } else if (ret < len) {
+ msgb_free(msg);
+ return -EIO;
+ }
+ msgb_put(msg, ret);
+ *rmsg = msg;
+ return ret;
+}
+
+void ipa_client_link_close(struct ipa_link *link);
+
+static void ipa_client_retry(struct ipa_link *link)
+{
+ LOGP(DINP, LOGL_NOTICE, "connection closed\n");
+ ipa_client_link_close(link);
+ LOGP(DINP, LOGL_NOTICE, "retrying in 5 seconds...\n");
+ osmo_timer_schedule(&link->timer, 5, 0);
+ link->state = IPA_LINK_STATE_CONNECTING;
+}
+
+void ipa_client_link_close(struct ipa_link *link)
+{
+ osmo_fd_unregister(&link->ofd);
+ close(link->ofd.fd);
+}
+
+static void ipa_client_read(struct ipa_link *link)
+{
+ struct osmo_fd *ofd = &link->ofd;
+ struct msgb *msg;
+ int ret;
+
+ LOGP(DINP, LOGL_NOTICE, "message received\n");
+
+ ret = ipa_msg_recv(ofd->fd, &msg);
+ if (ret < 0) {
+ if (errno == EPIPE || errno == ECONNRESET) {
+ LOGP(DINP, LOGL_ERROR, "lost connection with server\n");
+ } else {
+ LOGP(DINP, LOGL_ERROR, "unknown error\n");
+ }
+ ipa_client_retry(link);
+ return;
+ } else if (ret == 0) {
+ LOGP(DINP, LOGL_ERROR, "connection closed with server\n");
+ ipa_client_retry(link);
+ return;
+ }
+ if (link->process)
+ link->process(link, msg);
+}
+
+static void ipa_client_write(struct ipa_link *link)
+{
+ struct osmo_fd *ofd = &link->ofd;
+ struct msgb *msg;
+ struct llist_head *lh;
+ int ret;
+
+ LOGP(DINP, LOGL_NOTICE, "sending data\n");
+
+ if (llist_empty(&link->tx_queue)) {
+ ofd->when &= ~BSC_FD_WRITE;
+ return;
+ }
+ lh = link->tx_queue.next;
+ llist_del(lh);
+ msg = llist_entry(lh, struct msgb, list);
+
+ ret = send(link->ofd.fd, msg->data, msg->len, 0);
+ if (ret < 0) {
+ if (errno == EPIPE || errno == ENOTCONN) {
+ ipa_client_retry(link);
+ }
+ LOGP(DINP, LOGL_ERROR, "error to send\n");
+ }
+ msgb_free(msg);
+}
+
+int ipa_client_fd_cb(struct osmo_fd *ofd, unsigned int what)
+{
+ struct ipa_link *link = ofd->data;
+ int error, ret;
+ size_t len = sizeof(error);
+
+ switch(link->state) {
+ case IPA_LINK_STATE_CONNECTING:
+ ret = getsockopt(ofd->fd, SOL_SOCKET, SO_ERROR, &error, &len);
+ if (ret >= 0 && error > 0) {
+ ipa_client_retry(link);
+ return 0;
+ }
+ ofd->when &= ~BSC_FD_WRITE;
+ LOGP(DINP, LOGL_NOTICE, "connection done.\n");
+ link->state = IPA_LINK_STATE_CONNECTED;
+ break;
+ case IPA_LINK_STATE_CONNECTED:
+ LOGP(DINP, LOGL_NOTICE, "connected read/write\n");
+ if (what & BSC_FD_READ)
+ ipa_client_read(link);
+ if (what & BSC_FD_WRITE)
+ ipa_client_write(link);
+ break;
+ default:
+ break;
+ }
+ return 0;
+}
+
+static void ipa_link_timer_cb(void *data);
+
+struct ipa_link *ipa_client_link_create(void *ctx)
+{
+ struct ipa_link *ipa_link;
+
+ ipa_link = talloc_zero(ctx, struct ipa_link);
+ if (!ipa_link)
+ return NULL;
+
+ ipa_link->ofd.when |= BSC_FD_READ | BSC_FD_WRITE;
+ ipa_link->ofd.cb = ipa_client_fd_cb;
+ ipa_link->ofd.data = ipa_link;
+ ipa_link->state = IPA_LINK_STATE_CONNECTING;
+ ipa_link->timer.cb = ipa_link_timer_cb;
+ ipa_link->timer.data = ipa_link;
+
+ return ipa_link;
+}
+
+void ipa_client_link_destroy(struct ipa_link *link)
+{
+ talloc_free(link);
+}
+
+int ipa_client_link_open(struct ipa_link *link)
+{
+ int ret;
+
+ ret = osmo_sock_init(AF_INET, SOCK_STREAM, IPPROTO_TCP,
+ "127.0.0.1", IPA_TCP_PORT_OML,
+ OSMO_SOCK_F_CONNECT|OSMO_SOCK_F_NONBLOCK);
+ if (ret < 0) {
+ if (errno != EINPROGRESS)
+ return ret;
+ }
+ link->ofd.fd = ret;
+ if (osmo_fd_register(&link->ofd) < 0) {
+ close(ret);
+ return -EIO;
+ }
+ return 0;
+}
+
+static void ipa_link_timer_cb(void *data)
+{
+ struct ipa_link *link = data;
+
+ LOGP(DINP, LOGL_NOTICE, "reconnecting.\n");
+
+ switch(link->state) {
+ case IPA_LINK_STATE_CONNECTING:
+ ipa_client_link_open(link);
+ break;
+ default:
+ break;
+ }
+}
diff --git a/src/input/ipaccess.c b/src/input/ipaccess.c
index 78b2533..4a86300 100644
--- a/src/input/ipaccess.c
+++ b/src/input/ipaccess.c
@@ -43,6 +43,7 @@
#include <osmocom/abis/ipaccess.h>
#include <osmocom/core/socket.h>
#include <osmocom/abis/logging.h>
+#include <osmocom/abis/ipa.h>
#define PRIV_OML 1
#define PRIV_RSL 2
@@ -485,9 +486,12 @@
switch(role) {
case E1INP_LINE_R_BSC:
+ LOGP(DINP, LOGL_NOTICE, "enabling ipaccess BSC mode\n");
+
/* Listen for OML connections */
ret = osmo_sock_init(AF_INET, SOCK_STREAM, IPPROTO_TCP,
- "0.0.0.0", IPA_TCP_PORT_OML, 1);
+ "0.0.0.0", IPA_TCP_PORT_OML,
+ OSMO_SOCK_F_BIND);
if (ret < 0)
return ret;
@@ -502,7 +506,8 @@
}
/* Listen for RSL connections */
ret = osmo_sock_init(AF_INET, SOCK_STREAM, IPPROTO_TCP,
- "0.0.0.0", IPA_TCP_PORT_RSL, 1);
+ "0.0.0.0", IPA_TCP_PORT_RSL,
+ OSMO_SOCK_F_BIND);
if (ret < 0)
return ret;
@@ -516,9 +521,25 @@
return ret;
}
break;
- case E1INP_LINE_R_BTS:
- /* XXX: no implemented yet. */
+ case E1INP_LINE_R_BTS: {
+ struct ipa_link *link;
+
+ LOGP(DINP, LOGL_NOTICE, "enabling ipaccess BTS mode\n");
+
+ link = ipa_client_link_create(tall_ipa_ctx);
+ if (link == NULL) {
+ perror("ipa_client_link_create: ");
+ return -ENOMEM;
+ }
+ if (ipa_client_link_open(link) < 0) {
+ perror("ipa_client_link_open: ");
+ ipa_client_link_close(link);
+ ipa_client_link_destroy(link);
+ return -EIO;
+ }
+ ret = 0;
break;
+ }
default:
break;
}