diff options
Diffstat (limited to 'openbsc/src/e1_input.c')
-rw-r--r-- | openbsc/src/e1_input.c | 498 |
1 files changed, 498 insertions, 0 deletions
diff --git a/openbsc/src/e1_input.c b/openbsc/src/e1_input.c new file mode 100644 index 000000000..c3c7c7597 --- /dev/null +++ b/openbsc/src/e1_input.c @@ -0,0 +1,498 @@ +/* OpenBSC Abis interface to E1 */ + +/* (C) 2008-2009 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 <mISDNif.h> + +//#define AF_COMPATIBILITY_FUNC +//#include <compat_af_isdn.h> +#ifndef AF_ISDN +#define AF_ISDN 34 +#define PF_ISDN AF_ISDN +#endif + +#include <openbsc/select.h> +#include <openbsc/msgb.h> +#include <openbsc/debug.h> +#include <openbsc/gsm_data.h> +#include <openbsc/e1_input.h> +#include <openbsc/abis_nm.h> +#include <openbsc/abis_rsl.h> +#include <openbsc/linuxlist.h> +#include <openbsc/subchan_demux.h> +#include <openbsc/trau_frame.h> +#include <openbsc/trau_mux.h> + +#define NUM_E1_TS 32 + +/* list of all E1 drivers */ +LLIST_HEAD(e1inp_driver_list); + +/* list of all E1 lines */ +LLIST_HEAD(e1inp_line_list); + +/* to be implemented, e.g. by bsc_hack.c */ +void input_event(int event, enum e1inp_sign_type type, struct gsm_bts_trx *trx); + +/* + * pcap writing of the misdn load + * pcap format is from http://wiki.wireshark.org/Development/LibpcapFileFormat + */ +#define DLT_LINUX_LAPD 177 +#define PCAP_INPUT 0 +#define PCAP_OUTPUT 1 + +struct pcap_hdr { + u_int32_t magic_number; + u_int16_t version_major; + u_int16_t version_minor; + int32_t thiszone; + u_int32_t sigfigs; + u_int32_t snaplen; + u_int32_t network; +} __attribute__((packed)); + +struct pcaprec_hdr { + u_int32_t ts_sec; + u_int32_t ts_usec; + u_int32_t incl_len; + u_int32_t orig_len; +} __attribute__((packed)); + +struct fake_linux_lapd_header { + u_int16_t pkttype; + u_int16_t hatype; + u_int16_t halen; + u_int64_t addr; + int16_t protocol; +} __attribute__((packed)); + +struct lapd_header { + u_int8_t ea1 : 1; + u_int8_t cr : 1; + u_int8_t sapi : 6; + u_int8_t ea2 : 1; + u_int8_t tei : 7; + u_int8_t control_foo; /* fake UM's ... */ +} __attribute__((packed)); + +static_assert((int)&((struct fake_linux_lapd_header*)NULL)->hatype == 2, hatype_offset); +static_assert((int)&((struct fake_linux_lapd_header*)NULL)->halen == 4, halen_offset); +static_assert((int)&((struct fake_linux_lapd_header*)NULL)->addr == 6, addr_offset); +static_assert((int)&((struct fake_linux_lapd_header*)NULL)->protocol == 14, proto_offset); +static_assert(sizeof(struct fake_linux_lapd_header) == 16, lapd_header_size); + + +static int pcap_fd = -1; + +void e1_set_pcap_fd(int fd) +{ + int ret; + struct pcap_hdr header = { + .magic_number = 0xa1b2c3d4, + .version_major = 2, + .version_minor = 4, + .thiszone = 0, + .sigfigs = 0, + .snaplen = 65535, + .network = DLT_LINUX_LAPD, + }; + + pcap_fd = fd; + ret = write(pcap_fd, &header, sizeof(header)); +} + +/* This currently only works for the D-Channel */ +static void write_pcap_packet(int direction, int sapi, int tei, + struct msgb *msg) { + if (pcap_fd < 0) + return; + + int ret; + time_t cur_time; + struct tm *tm; + + struct fake_linux_lapd_header header = { + .pkttype = 4, + .hatype = 0, + .halen = 0, + .addr = direction == PCAP_OUTPUT ? 0x0 : 0x1, + .protocol = ntohs(48), + }; + + struct lapd_header lapd_header = { + .ea1 = 0, + .cr = direction == PCAP_OUTPUT ? 1 : 0, + .sapi = sapi & 0x3F, + .ea2 = 1, + .tei = tei & 0x7F, + .control_foo = 0x03 /* UI */, + }; + + struct pcaprec_hdr payload_header = { + .ts_sec = 0, + .ts_usec = 0, + .incl_len = msg->len + sizeof(struct fake_linux_lapd_header) + + sizeof(struct lapd_header) + - MISDN_HEADER_LEN, + .orig_len = msg->len + sizeof(struct fake_linux_lapd_header) + + sizeof(struct lapd_header) + - MISDN_HEADER_LEN, + }; + + + cur_time = time(NULL); + tm = localtime(&cur_time); + payload_header.ts_sec = mktime(tm); + + ret = write(pcap_fd, &payload_header, sizeof(payload_header)); + ret = write(pcap_fd, &header, sizeof(header)); + ret = write(pcap_fd, &lapd_header, sizeof(lapd_header)); + ret = write(pcap_fd, msg->data + MISDN_HEADER_LEN, + msg->len - MISDN_HEADER_LEN); +} + +static const char *sign_types[] = { + [E1INP_SIGN_NONE] = "None", + [E1INP_SIGN_OML] = "OML", + [E1INP_SIGN_RSL] = "RSL", +}; +const char *e1inp_signtype_name(enum e1inp_sign_type tp) +{ + if (tp >= ARRAY_SIZE(sign_types)) + return "undefined"; + return sign_types[tp]; +} + +static const char *ts_types[] = { + [E1INP_TS_TYPE_NONE] = "None", + [E1INP_TS_TYPE_SIGN] = "Signalling", + [E1INP_TS_TYPE_TRAU] = "TRAU", +}; + +const char *e1inp_tstype_name(enum e1inp_ts_type tp) +{ + if (tp >= ARRAY_SIZE(ts_types)) + return "undefined"; + return ts_types[tp]; +} + +/* callback when a TRAU frame was received */ +static int subch_cb(struct subch_demux *dmx, int ch, u_int8_t *data, int len, + void *_priv) +{ + struct e1inp_ts *e1i_ts = _priv; + struct gsm_e1_subslot src_ss; + + src_ss.e1_nr = e1i_ts->line->num; + src_ss.e1_ts = e1i_ts->num; + src_ss.e1_ts_ss = ch; + + return trau_mux_input(&src_ss, data, len); +} + +int abis_rsl_sendmsg(struct msgb *msg) +{ + struct e1inp_sign_link *sign_link; + struct e1inp_driver *e1inp_driver; + struct e1inp_ts *e1i_ts; + + msg->l2h = msg->data; + + if (!msg->trx || !msg->trx->rsl_link) { + fprintf(stderr, "rsl_sendmsg: msg->trx == NULL\n"); + return -EINVAL; + } + + sign_link = msg->trx->rsl_link; + e1i_ts = sign_link->ts; + if (!bsc_timer_pending(&e1i_ts->sign.tx_timer)) { + /* notify the driver we have something to write */ + e1inp_driver = sign_link->ts->line->driver; + e1inp_driver->want_write(e1i_ts); + } + msgb_enqueue(&sign_link->tx_list, msg); + + /* dump it */ + write_pcap_packet(PCAP_OUTPUT, sign_link->sapi, sign_link->tei, msg); + + return 0; +} + +int _abis_nm_sendmsg(struct msgb *msg) +{ + struct e1inp_sign_link *sign_link; + struct e1inp_driver *e1inp_driver; + struct e1inp_ts *e1i_ts; + + msg->l2h = msg->data; + + if (!msg->trx || !msg->trx->bts || !msg->trx->bts->oml_link) { + fprintf(stderr, "nm_sendmsg: msg->trx == NULL\n"); + return -EINVAL; + } + + sign_link = msg->trx->bts->oml_link; + e1i_ts = sign_link->ts; + if (!bsc_timer_pending(&e1i_ts->sign.tx_timer)) { + /* notify the driver we have something to write */ + e1inp_driver = sign_link->ts->line->driver; + e1inp_driver->want_write(e1i_ts); + } + msgb_enqueue(&sign_link->tx_list, msg); + + /* dump it */ + write_pcap_packet(PCAP_OUTPUT, sign_link->sapi, sign_link->tei, msg); + + return 0; +} + +/* Timeslot */ + +/* configure and initialize one e1inp_ts */ +int e1inp_ts_config(struct e1inp_ts *ts, struct e1inp_line *line, + enum e1inp_ts_type type) +{ + ts->type = type; + ts->line = line; + + switch (type) { + case E1INP_TS_TYPE_SIGN: + INIT_LLIST_HEAD(&ts->sign.sign_links); + break; + case E1INP_TS_TYPE_TRAU: + subchan_mux_init(&ts->trau.mux); + ts->trau.demux.out_cb = subch_cb; + ts->trau.demux.data = ts; + subch_demux_init(&ts->trau.demux); + break; + default: + fprintf(stderr, "unsupported E1 timeslot type %u\n", + ts->type); + return -EINVAL; + } + return 0; +} + +static struct e1inp_line *e1inp_line_get(u_int8_t e1_nr) +{ + struct e1inp_line *e1i_line; + + /* iterate over global list of e1 lines */ + llist_for_each_entry(e1i_line, &e1inp_line_list, list) { + if (e1i_line->num == e1_nr) + return e1i_line; + } + return NULL; +} + +static struct e1inp_ts *e1inp_ts_get(u_int8_t e1_nr, u_int8_t ts_nr) +{ + struct e1inp_line *e1i_line; + + e1i_line = e1inp_line_get(e1_nr); + if (!e1i_line) + return NULL; + + return &e1i_line->ts[ts_nr-1]; +} + +struct subch_mux *e1inp_get_mux(u_int8_t e1_nr, u_int8_t ts_nr) +{ + struct e1inp_ts *e1i_ts = e1inp_ts_get(e1_nr, ts_nr); + + if (!e1i_ts) + return NULL; + + return &e1i_ts->trau.mux; +} + +/* Signalling Link */ + +struct e1inp_sign_link *e1inp_lookup_sign_link(struct e1inp_ts *e1i, + u_int8_t tei, u_int8_t sapi) +{ + struct e1inp_sign_link *link; + + llist_for_each_entry(link, &e1i->sign.sign_links, list) { + if (link->sapi == sapi && link->tei == tei) + return link; + } + + return NULL; +} + +/* create a new signalling link in a E1 timeslot */ + +struct e1inp_sign_link * +e1inp_sign_link_create(struct e1inp_ts *ts, enum e1inp_sign_type type, + struct gsm_bts_trx *trx, u_int8_t tei, + u_int8_t sapi) +{ + struct e1inp_sign_link *link; + + if (ts->type != E1INP_TS_TYPE_SIGN) + return NULL; + + link = malloc(sizeof(*link)); + if (!link) + return NULL; + + memset(link, 0, sizeof(*link)); + + link->ts = ts; + link->type = type; + INIT_LLIST_HEAD(&link->tx_list); + link->trx = trx; + link->tei = tei; + link->sapi = sapi; + + llist_add_tail(&link->list, &ts->sign.sign_links); + + return link; +} + +/* the E1 driver tells us he has received something on a TS */ +int e1inp_rx_ts(struct e1inp_ts *ts, struct msgb *msg, + u_int8_t tei, u_int8_t sapi) +{ + struct e1inp_sign_link *link; + int ret; + + switch (ts->type) { + case E1INP_TS_TYPE_SIGN: + /* consult the list of signalling links */ + write_pcap_packet(PCAP_INPUT, sapi, tei, msg); + link = e1inp_lookup_sign_link(ts, tei, sapi); + if (!link) { + fprintf(stderr, "didn't find singalling link for " + "tei %d, sapi %d\n", tei, sapi); + return -EINVAL; + } + switch (link->type) { + case E1INP_SIGN_OML: + msg->trx = link->trx; + ret = abis_nm_rcvmsg(msg); + break; + case E1INP_SIGN_RSL: + msg->trx = link->trx; + ret = abis_rsl_rcvmsg(msg); + break; + default: + ret = -EINVAL; + fprintf(stderr, "unknown link type %u\n", link->type); + break; + } + break; + case E1INP_TS_TYPE_TRAU: + ret = subch_demux_in(&ts->trau.demux, msg->l2h, msgb_l2len(msg)); + break; + default: + ret = -EINVAL; + fprintf(stderr, "unknown TS type %u\n", ts->type); + break; + } + + return ret; +} + +#define TSX_ALLOC_SIZE 4096 + +/* called by driver if it wants to transmit on a given TS */ +struct msgb *e1inp_tx_ts(struct e1inp_ts *e1i_ts, + struct e1inp_sign_link **sign_link) +{ + struct e1inp_sign_link *link; + struct msgb *msg = NULL; + int len; + + switch (e1i_ts->type) { + case E1INP_TS_TYPE_SIGN: + /* FIXME: implement this round robin */ + llist_for_each_entry(link, &e1i_ts->sign.sign_links, list) { + msg = msgb_dequeue(&link->tx_list); + if (msg) { + if (sign_link) + *sign_link = link; + break; + } + } + break; + case E1INP_TS_TYPE_TRAU: + msg = msgb_alloc(TSX_ALLOC_SIZE); + if (!msg) + return NULL; + len = subchan_mux_out(&e1i_ts->trau.mux, msg->data, 40); + msgb_put(msg, 40); + break; + default: + fprintf(stderr, "unsupported E1 TS type %u\n", e1i_ts->type); + return NULL; + } + return msg; +} + +/* called by driver in case some kind of link state event */ +int e1inp_event(struct e1inp_ts *ts, int evt, u_int8_t tei, u_int8_t sapi) +{ + struct e1inp_sign_link *link; + + link = e1inp_lookup_sign_link(ts, tei, sapi); + if (!link) + return -EINVAL; + + /* FIXME: report further upwards */ + input_event(evt, link->type, link->trx); + return 0; +} + +/* register a driver with the E1 core */ +int e1inp_driver_register(struct e1inp_driver *drv) +{ + llist_add_tail(&drv->list, &e1inp_driver_list); + return 0; +} + +/* register a line with the E1 core */ +int e1inp_line_register(struct e1inp_line *line) +{ + int i; + + for (i = 0; i < NUM_E1_TS; i++) { + line->ts[i].num = i+1; + line->ts[i].line = line; + } + + llist_add_tail(&line->list, &e1inp_line_list); + + return 0; +} |