preliminary ip.access BTS support, as of now only OML singalling works

include/openbsc/e1_input.h

@@ -75,6 +75,11 @@ struct e1inp_ts {
 			/* mISDN driver has one fd for each ts */
 			struct bsc_fd fd;
 		} misdn;
+		struct {
+			/* ip.access driver has one fd for each ts */
+			struct bsc_fd fd;
+		} ipaccess;
+
 	} driver;
 };
 

src/Makefile.am

@@ -7,7 +7,7 @@ bsc_hack_SOURCES = bsc_hack.c abis_rsl.c abis_nm.c gsm_04_08.c gsm_data.c \
 		gsm_subscriber.c msgb.c select.c chan_alloc.c timer.c debug.c db.c \
 		gsm_04_11.c telnet_interface.c telnet_parser.l subchan_demux.c \
 		trau_frame.c trau_mux.c paging.c e1_config.c e1_input.c \
-		input/misdn.c
+		input/misdn.c input/ipaccess.c
 bsc_hack_LDADD = -ldl -ldbi
 
 bs11_config_SOURCES = bs11_config.c abis_nm.c gsm_data.c msgb.c debug.c select.c timer.c rs232.c

src/e1_config.c

@@ -66,3 +66,32 @@ int e1_config(struct gsm_bts *bts)
 
 	return mi_setup(0, line, NULL);
 }
+
+/* do some compiled-in configuration for our BTS/E1 setup */
+int ia_config(struct gsm_bts *bts)
+{
+	struct e1inp_line *line;
+	struct e1inp_ts *sign_ts;
+	struct e1inp_sign_link *oml_link, *rsl_link;
+
+	line = malloc(sizeof(*line));
+	if (!line)
+		return -ENOMEM;
+	memset(line, 0, sizeof(*line));
+
+	/* create E1 timeslots for signalling and TRAU frames */
+	e1inp_ts_config(&line->ts[1-1], line, E1INP_TS_TYPE_SIGN);
+
+	/* create signalling links for TS1 */
+	sign_ts = &line->ts[1-1];
+	oml_link = e1inp_sign_link_create(sign_ts, E1INP_SIGN_OML,
+					  bts->c0, 0, 0xff);
+	rsl_link = e1inp_sign_link_create(sign_ts, E1INP_SIGN_RSL,
+					  bts->c0, 0, 0);
+
+	/* create back-links from bts/trx */
+	bts->oml_link = oml_link;
+	bts->c0->rsl_link = rsl_link;
+
+	return ipaccess_setup(line);
+}

src/input/ipaccess.c

@@ -0,0 +1,370 @@
+/* OpenBSC Abis input driver for ip.access */
+
+/* (C) 2009 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <time.h>
+#include <sys/fcntl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+
+#include <openbsc/select.h>
+#include <openbsc/msgb.h>
+#include <openbsc/debug.h>
+#include <openbsc/gsm_data.h>
+#include <openbsc/abis_nm.h>
+#include <openbsc/abis_rsl.h>
+#include <openbsc/subchan_demux.h>
+#include <openbsc/e1_input.h>
+
+/* data structure for one E1 interface with A-bis */
+struct ia_e1_handle {
+	struct bsc_fd listen_fd;
+};
+
+#define TS1_ALLOC_SIZE	300
+
+struct ipaccess_head {
+	u_int8_t zero;
+	u_int8_t len;
+	u_int8_t proto;
+	u_int8_t data[0];
+} __attribute__ ((packed));
+
+enum ipaccess_proto {
+	PROTO_RSL = 0x00,
+	PROTO_IPACCESS = 0xfe,
+	PROTO_OML = 0xff,
+};
+
+enum ipaccess_msg_type {
+	MSGT_PING		= 0x00,
+	MSGT_PONG		= 0x01,
+	MSGT_IDENTITY_GET	= 0x04,
+	MSGT_IDENTITY_RESP	= 0x05,
+	MSGT_IDENTITY_ACK	= 0x06,
+};
+
+static const u_int8_t pong[] = { 0, 1, PROTO_IPACCESS, MSGT_PONG };
+static const u_int8_t id_ack[] = { 0, 1, PROTO_IPACCESS, MSGT_IDENTITY_ACK };
+
+static int ipaccess_rcvmsg(struct msgb *msg, int fd)
+{
+	u_int8_t msg_type = *(msg->l2h);
+
+	printf("msg_type=0x%02x\n", msg_type);
+	switch (msg_type) {
+	case MSGT_PING:
+		DEBUGP(DMI, "PING?\n");
+		write(fd, pong, sizeof(pong));
+		break;
+	case MSGT_PONG:
+		DEBUGP(DMI, "PONG!\n");
+		break;
+	case MSGT_IDENTITY_RESP:
+		DEBUGP(DMI, "ID_RESP\n");
+		break;
+	case MSGT_IDENTITY_ACK:
+		DEBUGP(DMI, "ID_ACK\n");
+		write(fd, id_ack, sizeof(id_ack));
+		break;	
+	}
+
+	msgb_free(msg);
+	return 0;
+}
+
+static int handle_ts1_read(struct bsc_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct e1inp_sign_link *link;
+	struct msgb *msg = msgb_alloc(TS1_ALLOC_SIZE);
+	struct ipaccess_head *hh;
+	int ret;
+
+	if (!msg)
+		return -ENOMEM;
+
+	/* first read our 3-byte header */
+	hh = (struct ipaccess_head *) msg->data;
+	ret = recv(bfd->fd, msg->data, 3, 0);
+	if (ret < 0) {
+		fprintf(stderr, "recv error  %s\n", strerror(errno));
+		return ret;
+	}
+	if (ret == 0) {
+		fprintf(stderr, "BTS disappeared, dead socket\n");
+		bsc_unregister_fd(bfd);
+		close(bfd->fd);
+		bfd->fd = -1;
+	}
+	msgb_put(msg, ret);
+
+	/* then read te length as specified in header */
+	msg->l2h = msg->data + sizeof(*hh);
+	ret = recv(bfd->fd, msg->l2h, hh->len, 0);
+	if (ret < hh->len) {
+		fprintf(stderr, "short read!\n");
+		//msgb_free(msg);
+		//return -EIO;
+	}
+	msgb_put(msg, ret);
+	DEBUGP(DMI, "<= ret=%d, len=%d, proto=0x%02x\n", ret, hh->len, hh->proto);
+
+	if (hh->proto == PROTO_IPACCESS)
+		return ipaccess_rcvmsg(msg, bfd->fd);
+
+	if (debug_mask & DMI) { 
+		fprintf(stdout, "RX: ");
+		hexdump(msgb_l2(msg), ret);
+	}
+
+	link = e1inp_lookup_sign_link(e1i_ts, 0, hh->proto);
+	if (!link) {
+		printf("no matching signalling link for hh->proto=0x%02x\n", hh->proto);
+		msgb_free(msg);
+		return -EIO;
+	}
+	msg->trx = link->trx;
+
+	switch (hh->proto) {
+	case PROTO_RSL:
+		ret = abis_rsl_rcvmsg(msg);
+		break;
+	case PROTO_OML:
+		ret = abis_nm_rcvmsg(msg);
+		break;
+	default:
+		msgb_free(msg);
+		break;
+	}
+	return ret;
+}
+
+static int handle_ts1_write(struct bsc_fd *bfd)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	struct e1inp_ts *e1i_ts = &line->ts[ts_nr-1];
+	struct e1inp_sign_link *sign_link;
+	struct msgb *msg;
+	struct ipaccess_head *hh;
+	u_int8_t *l2_data;
+	int ret;
+
+	/* get the next msg for this timeslot */
+	msg = e1inp_tx_ts(e1i_ts, &sign_link);
+	if (!msg) {
+		bfd->when &= ~BSC_FD_WRITE;
+		return 0;
+	}
+
+	l2_data = msg->data;
+
+	/* prepend the mISDNhead */
+	hh = (struct ipaccess_head *) msgb_push(msg, sizeof(*hh));
+	hh->zero = 0;
+	hh->len = msg->len - sizeof(*hh);
+
+	switch (sign_link->type) {
+	case E1INP_SIGN_OML:
+		hh->proto = PROTO_OML;
+		break;
+	case E1INP_SIGN_RSL:
+		hh->proto = PROTO_RSL;
+		break;
+	default:
+		msgb_free(msg);
+		return -EINVAL;
+	}
+
+	if (debug_mask & DMI) {
+		fprintf(stdout, "TX proto=0x%x: ", hh->proto);
+		hexdump(l2_data, hh->len);
+	}
+
+	ret = send(bfd->fd, msg->data, msg->len, 0);
+	msgb_free(msg);
+
+	return ret;
+}
+
+
+/* callback from select.c in case one of the fd's can be read/written */
+static int ipaccess_fd_cb(struct bsc_fd *bfd, unsigned int what)
+{
+	struct e1inp_line *line = bfd->data;
+	unsigned int ts_nr = bfd->priv_nr;
+	unsigned int idx = ts_nr-1;
+	struct e1inp_ts *e1i_ts = &line->ts[idx];
+	int rc = 0;
+
+	switch (e1i_ts->type) {
+	case E1INP_TS_TYPE_SIGN:
+		if (what & BSC_FD_READ)
+			rc = handle_ts1_read(bfd);
+		if (what & BSC_FD_WRITE)
+			rc = handle_ts1_write(bfd);
+		break;
+#if 0
+	case E1INP_TS_TYPE_TRAU:
+		if (what & BSC_FD_READ)
+			rc = handle_tsX_read(bfd);
+		/* We never include the mISDN B-Channel FD into the
+		 * writeset, since it doesn't support poll() based
+		 * write flow control */		
+		break;
+#endif
+	default:
+		fprintf(stderr, "unknown E1 TS type %u\n", e1i_ts->type);
+		break;
+	}
+
+	return rc;
+}
+
+
+static int ts_want_write(struct e1inp_ts *e1i_ts)
+{
+	/* We never include the mISDN B-Channel FD into the
+	 * writeset, since it doesn't support poll() based
+	 * write flow control */		
+	if (e1i_ts->type == E1INP_TS_TYPE_TRAU)
+		return 0;
+
+	e1i_ts->driver.ipaccess.fd.when |= BSC_FD_WRITE;
+
+	return 0;
+}
+
+struct e1inp_driver ipaccess_driver = {
+	.name = "ip.access",
+	.want_write = ts_want_write,
+};
+
+static int ia_e1_setup(struct e1inp_line *line)
+{
+	return 0;
+}
+
+static int listen_fd_cb(struct bsc_fd *listen_bfd, unsigned int what)
+{
+	struct e1inp_line *line = listen_bfd->data;
+	int ret;
+
+	if (what & BSC_FD_READ) {
+		int idx = 0;
+		struct e1inp_ts *e1i_ts = &line->ts[idx];
+		struct bsc_fd *bfd = &e1i_ts->driver.ipaccess.fd;
+		struct sockaddr_in sa;
+		socklen_t sa_len = sizeof(sa);
+
+		if (bfd->fd) {
+			printf("dumping old fd\n");
+			if (bfd->fd != -1) {
+				bsc_unregister_fd(bfd);
+				close(bfd->fd);
+			}
+		}
+		bfd->fd = accept(listen_bfd->fd, (struct sockaddr *) &sa, &sa_len);
+		if (bfd->fd < 0) {
+			perror("accept");
+			return bfd->fd;
+		}
+		printf("accept()ed new RSL/OML fd\n");
+		bfd->data = line;
+		bfd->priv_nr = 1;
+		bfd->cb = ipaccess_fd_cb;
+		bfd->when = BSC_FD_READ;
+		ret = bsc_register_fd(bfd);
+		if (ret < 0) {
+			fprintf(stderr, "could not register FD\n");
+			return ret;
+		}
+	}
+	return 0;
+}
+
+int ipaccess_setup(struct e1inp_line *line)
+{
+	struct sockaddr_in addr;
+	struct ia_e1_handle *e1h;
+	int sk, ret, on = 1;
+
+	/* register the driver with the core */
+	/* FIXME: do this in the plugin initializer function */
+	ret = e1inp_driver_register(&ipaccess_driver);
+	if (ret)
+		return ret;
+
+	/* create the actual line instance */
+	/* FIXME: do this independent of driver registration */
+	e1h = malloc(sizeof(*e1h));
+	memset(e1h, 0, sizeof(*e1h));
+
+	line->driver = &ipaccess_driver;
+	line->driver_data = e1h;
+
+	e1h->listen_fd.fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+	e1h->listen_fd.cb = listen_fd_cb;
+	e1h->listen_fd.when = BSC_FD_READ;
+	e1h->listen_fd.data = line;
+
+	memset(&addr, 0, sizeof(addr));
+	addr.sin_family = AF_INET;
+	addr.sin_port = htons(3002);
+	addr.sin_addr.s_addr = INADDR_ANY;
+
+	setsockopt(e1h->listen_fd.fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on));
+
+	ret = bind(e1h->listen_fd.fd, (struct sockaddr *) &addr, sizeof(addr));
+	if (ret < 0) {
+		fprintf(stderr, "could not bind l2 socket %s\n",
+			strerror(errno));
+		return -EIO;
+	}
+
+	ret = listen(e1h->listen_fd.fd, 1);
+	if (ret < 0) {
+		perror("listen");
+		return ret;
+	}
+	
+	ret = bsc_register_fd(&e1h->listen_fd);
+	if (ret < 0) {
+		perror("register_listen_fd");
+		return ret;
+	}
+
+	ret = ia_e1_setup(line);
+	if (ret)
+		return ret;
+
+	return e1inp_line_register(line);
+}