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Diffstat (limited to 'src/gprs/gprs_sndcp.c')
| -rw-r--r-- | src/gprs/gprs_sndcp.c | 1258 |
1 files changed, 0 insertions, 1258 deletions
diff --git a/src/gprs/gprs_sndcp.c b/src/gprs/gprs_sndcp.c deleted file mode 100644 index a18998f9e..000000000 --- a/src/gprs/gprs_sndcp.c +++ /dev/null @@ -1,1258 +0,0 @@ -/* GPRS SNDCP protocol implementation as per 3GPP TS 04.65 */ - -/* (C) 2010 by Harald Welte <laforge@gnumonks.org> - * (C) 2010 by On-Waves - * - * All Rights Reserved - * - * 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 <errno.h> -#include <stdint.h> -#include <stdbool.h> - -#include <osmocom/core/msgb.h> -#include <osmocom/core/linuxlist.h> -#include <osmocom/core/timer.h> -#include <osmocom/core/talloc.h> -#include <osmocom/gprs/gprs_bssgp.h> - -#include <openbsc/gsm_data.h> -#include <openbsc/debug.h> -#include <openbsc/gprs_llc.h> -#include <openbsc/sgsn.h> -#include <openbsc/gprs_sndcp.h> -#include <openbsc/gprs_llc_xid.h> -#include <openbsc/gprs_sndcp_xid.h> -#include <openbsc/gprs_sndcp_pcomp.h> -#include <openbsc/gprs_sndcp_dcomp.h> -#include <openbsc/gprs_sndcp_comp.h> - -#define DEBUG_IP_PACKETS 0 /* 0=Disabled, 1=Enabled */ - -#if DEBUG_IP_PACKETS == 1 -/* Calculate TCP/IP checksum */ -static uint16_t calc_ip_csum(uint8_t *data, int len) -{ - int i; - uint32_t accumulator = 0; - uint16_t *pointer = (uint16_t *) data; - - for (i = len; i > 1; i -= 2) { - accumulator += *pointer; - pointer++; - } - - if (len % 2) - accumulator += *pointer; - - accumulator = (accumulator & 0xffff) + ((accumulator >> 16) & 0xffff); - accumulator += (accumulator >> 16) & 0xffff; - return (~accumulator); -} - -/* Calculate TCP/IP checksum */ -static uint16_t calc_tcpip_csum(const void *ctx, uint8_t *packet, int len) -{ - uint8_t *buf; - uint16_t csum; - - buf = talloc_zero_size(ctx, len); - memset(buf, 0, len); - memcpy(buf, packet + 12, 8); - buf[9] = packet[9]; - buf[11] = (len - 20) & 0xFF; - buf[10] = (len - 20) >> 8 & 0xFF; - memcpy(buf + 12, packet + 20, len - 20); - csum = calc_ip_csum(buf, len - 20 + 12); - talloc_free(buf); - return csum; -} - -/* Show some ip packet details */ -static void debug_ip_packet(uint8_t *data, int len, int dir, char *info) -{ - uint8_t tcp_flags; - char flags_debugmsg[256]; - int len_short; - static unsigned int packet_count = 0; - static unsigned int tcp_csum_err_count = 0; - static unsigned int ip_csum_err_count = 0; - - packet_count++; - - if (len > 80) - len_short = 80; - else - len_short = len; - - if (dir) - DEBUGP(DSNDCP, "%s: MS => SGSN: %s\n", info, - osmo_hexdump_nospc(data, len_short)); - else - DEBUGP(DSNDCP, "%s: MS <= SGSN: %s\n", info, - osmo_hexdump_nospc(data, len_short)); - - DEBUGP(DSNDCP, "%s: Length.: %d\n", info, len); - DEBUGP(DSNDCP, "%s: NO.: %d\n", info, packet_count); - - if (len < 20) { - DEBUGP(DSNDCP, "%s: Error: Short IP packet!\n", info); - return; - } - - if (calc_ip_csum(data, 20) != 0) { - DEBUGP(DSNDCP, "%s: Bad IP-Header checksum!\n", info); - ip_csum_err_count++; - } else - DEBUGP(DSNDCP, "%s: IP-Header checksum ok.\n", info); - - if (data[9] == 0x06) { - if (len < 40) { - DEBUGP(DSNDCP, "%s: Error: Short TCP packet!\n", info); - return; - } - - DEBUGP(DSNDCP, "%s: Protocol type: TCP\n", info); - tcp_flags = data[33]; - - if (calc_tcpip_csum(NULL, data, len) != 0) { - DEBUGP(DSNDCP, "%s: Bad TCP checksum!\n", info); - tcp_csum_err_count++; - } else - DEBUGP(DSNDCP, "%s: TCP checksum ok.\n", info); - - memset(flags_debugmsg, 0, sizeof(flags_debugmsg)); - if (tcp_flags & 1) - strcat(flags_debugmsg, "FIN "); - if (tcp_flags & 2) - strcat(flags_debugmsg, "SYN "); - if (tcp_flags & 4) - strcat(flags_debugmsg, "RST "); - if (tcp_flags & 8) - strcat(flags_debugmsg, "PSH "); - if (tcp_flags & 16) - strcat(flags_debugmsg, "ACK "); - if (tcp_flags & 32) - strcat(flags_debugmsg, "URG "); - DEBUGP(DSNDCP, "%s: FLAGS: %s\n", info, flags_debugmsg); - } else if (data[9] == 0x11) { - DEBUGP(DSNDCP, "%s: Protocol type: UDP\n", info); - } else { - DEBUGP(DSNDCP, "%s: Protocol type: (%02x)\n", info, data[9]); - } - - DEBUGP(DSNDCP, "%s: IP-Header checksum errors: %d\n", info, - ip_csum_err_count); - DEBUGP(DSNDCP, "%s: TCP-Checksum errors: %d\n", info, - tcp_csum_err_count); -} -#endif - -/* Chapter 7.2: SN-PDU Formats */ -struct sndcp_common_hdr { - /* octet 1 */ - uint8_t nsapi:4; - uint8_t more:1; - uint8_t type:1; - uint8_t first:1; - uint8_t spare:1; -} __attribute__((packed)); - -/* PCOMP / DCOMP only exist in first fragment */ -struct sndcp_comp_hdr { - /* octet 2 */ - uint8_t pcomp:4; - uint8_t dcomp:4; -} __attribute__((packed)); - -struct sndcp_udata_hdr { - /* octet 3 */ - uint8_t npdu_high:4; - uint8_t seg_nr:4; - /* octet 4 */ - uint8_t npdu_low; -} __attribute__((packed)); - - -static void *tall_sndcp_ctx; - -/* A fragment queue entry, containing one framgent of a N-PDU */ -struct defrag_queue_entry { - struct llist_head list; - /* segment number of this fragment */ - uint32_t seg_nr; - /* length of the data area of this fragment */ - uint32_t data_len; - /* pointer to the data of this fragment */ - uint8_t *data; -}; - -LLIST_HEAD(gprs_sndcp_entities); - -/* Check if any compression parameters are set in the sgsn configuration */ -static inline int any_pcomp_or_dcomp_active(struct sgsn_instance *sgsn) { - if (sgsn->cfg.pcomp_rfc1144.active || sgsn->cfg.pcomp_rfc1144.passive || - sgsn->cfg.dcomp_v42bis.active || sgsn->cfg.dcomp_v42bis.passive) - return true; - else - return false; -} - -/* Enqueue a fragment into the defragment queue */ -static int defrag_enqueue(struct gprs_sndcp_entity *sne, uint8_t seg_nr, - uint8_t *data, uint32_t data_len) -{ - struct defrag_queue_entry *dqe; - - dqe = talloc_zero(tall_sndcp_ctx, struct defrag_queue_entry); - if (!dqe) - return -ENOMEM; - dqe->data = talloc_zero_size(dqe, data_len); - if (!dqe->data) { - talloc_free(dqe); - return -ENOMEM; - } - dqe->seg_nr = seg_nr; - dqe->data_len = data_len; - - llist_add(&dqe->list, &sne->defrag.frag_list); - - if (seg_nr > sne->defrag.highest_seg) - sne->defrag.highest_seg = seg_nr; - - sne->defrag.seg_have |= (1 << seg_nr); - sne->defrag.tot_len += data_len; - - memcpy(dqe->data, data, data_len); - - return 0; -} - -/* return if we have all segments of this N-PDU */ -static int defrag_have_all_segments(struct gprs_sndcp_entity *sne) -{ - uint32_t seg_needed = 0; - unsigned int i; - - /* create a bitmask of needed segments */ - for (i = 0; i <= sne->defrag.highest_seg; i++) - seg_needed |= (1 << i); - - if (seg_needed == sne->defrag.seg_have) - return 1; - - return 0; -} - -static struct defrag_queue_entry *defrag_get_seg(struct gprs_sndcp_entity *sne, - uint32_t seg_nr) -{ - struct defrag_queue_entry *dqe; - - llist_for_each_entry(dqe, &sne->defrag.frag_list, list) { - if (dqe->seg_nr == seg_nr) { - llist_del(&dqe->list); - return dqe; - } - } - return NULL; -} - -/* Perform actual defragmentation and create an output packet */ -static int defrag_segments(struct gprs_sndcp_entity *sne) -{ - struct msgb *msg; - unsigned int seg_nr; - uint8_t *npdu; - int npdu_len; - int rc; - uint8_t *expnd = NULL; - - LOGP(DSNDCP, LOGL_DEBUG, "TLLI=0x%08x NSAPI=%u: Defragment output PDU %u " - "num_seg=%u tot_len=%u\n", sne->lle->llme->tlli, sne->nsapi, - sne->defrag.npdu, sne->defrag.highest_seg, sne->defrag.tot_len); - msg = msgb_alloc_headroom(sne->defrag.tot_len+256, 128, "SNDCP Defrag"); - if (!msg) - return -ENOMEM; - - /* FIXME: message headers + identifiers */ - - npdu = msg->data; - - for (seg_nr = 0; seg_nr <= sne->defrag.highest_seg; seg_nr++) { - struct defrag_queue_entry *dqe; - uint8_t *data; - - dqe = defrag_get_seg(sne, seg_nr); - if (!dqe) { - LOGP(DSNDCP, LOGL_ERROR, "Segment %u missing\n", seg_nr); - msgb_free(msg); - return -EIO; - } - /* actually append the segment to the N-PDU */ - data = msgb_put(msg, dqe->data_len); - memcpy(data, dqe->data, dqe->data_len); - - /* release memory for the fragment queue entry */ - talloc_free(dqe); - } - - npdu_len = sne->defrag.tot_len; - - /* FIXME: cancel timer */ - - /* actually send the N-PDU to the SGSN core code, which then - * hands it off to the correct GTP tunnel + GGSN via gtp_data_req() */ - - /* Decompress packet */ -#if DEBUG_IP_PACKETS == 1 - DEBUGP(DSNDCP, " \n"); - DEBUGP(DSNDCP, ":::::::::::::::::::::::::::::::::::::::::::::::::::\n"); - DEBUGP(DSNDCP, "===================================================\n"); -#endif - if (any_pcomp_or_dcomp_active(sgsn)) { - - expnd = talloc_zero_size(msg, npdu_len * MAX_DATADECOMPR_FAC + - MAX_HDRDECOMPR_INCR); - memcpy(expnd, npdu, npdu_len); - - /* Apply data decompression */ - rc = gprs_sndcp_dcomp_expand(expnd, npdu_len, sne->defrag.dcomp, - sne->defrag.data); - if (rc < 0) { - LOGP(DSNDCP, LOGL_ERROR, - "Data decompression failed!\n"); - talloc_free(expnd); - return -EIO; - } - - /* Apply header decompression */ - rc = gprs_sndcp_pcomp_expand(expnd, rc, sne->defrag.pcomp, - sne->defrag.proto); - if (rc < 0) { - LOGP(DSNDCP, LOGL_ERROR, - "TCP/IP Header decompression failed!\n"); - talloc_free(expnd); - return -EIO; - } - - /* Modify npu length, expnd is handed directly handed - * over to gsn_rx_sndcp_ud_ind(), see below */ - npdu_len = rc; - } else - expnd = npdu; -#if DEBUG_IP_PACKETS == 1 - debug_ip_packet(expnd, npdu_len, 1, "defrag_segments()"); - DEBUGP(DSNDCP, "===================================================\n"); - DEBUGP(DSNDCP, ":::::::::::::::::::::::::::::::::::::::::::::::::::\n"); - DEBUGP(DSNDCP, " \n"); -#endif - - /* Hand off packet to gtp */ - rc = sgsn_rx_sndcp_ud_ind(&sne->ra_id, sne->lle->llme->tlli, - sne->nsapi, msg, npdu_len, expnd); - - if (any_pcomp_or_dcomp_active(sgsn)) - talloc_free(expnd); - - return rc; -} - -static int defrag_input(struct gprs_sndcp_entity *sne, struct msgb *msg, - uint8_t *hdr, unsigned int len) -{ - struct sndcp_common_hdr *sch; - struct sndcp_udata_hdr *suh; - uint16_t npdu_num; - uint8_t *data; - int rc; - - sch = (struct sndcp_common_hdr *) hdr; - if (sch->first) { - suh = (struct sndcp_udata_hdr *) (hdr + 1 + sizeof(struct sndcp_common_hdr)); - } else - suh = (struct sndcp_udata_hdr *) (hdr + sizeof(struct sndcp_common_hdr)); - - data = (uint8_t *)suh + sizeof(struct sndcp_udata_hdr); - - npdu_num = (suh->npdu_high << 8) | suh->npdu_low; - - LOGP(DSNDCP, LOGL_DEBUG, "TLLI=0x%08x NSAPI=%u: Input PDU %u Segment %u " - "Length %u %s %s\n", sne->lle->llme->tlli, sne->nsapi, npdu_num, - suh->seg_nr, len, sch->first ? "F " : "", sch->more ? "M" : ""); - - if (sch->first) { - /* first segment of a new packet. Discard all leftover fragments of - * previous packet */ - if (!llist_empty(&sne->defrag.frag_list)) { - struct defrag_queue_entry *dqe, *dqe2; - LOGP(DSNDCP, LOGL_INFO, "TLLI=0x%08x NSAPI=%u: Dropping " - "SN-PDU %u due to insufficient segments (%04x)\n", - sne->lle->llme->tlli, sne->nsapi, sne->defrag.npdu, - sne->defrag.seg_have); - llist_for_each_entry_safe(dqe, dqe2, &sne->defrag.frag_list, list) { - llist_del(&dqe->list); - talloc_free(dqe); - } - } - /* store the currently de-fragmented PDU number */ - sne->defrag.npdu = npdu_num; - - /* Re-set fragmentation state */ - sne->defrag.no_more = sne->defrag.highest_seg = sne->defrag.seg_have = 0; - sne->defrag.tot_len = 0; - /* FIXME: (re)start timer */ - } - - if (sne->defrag.npdu != npdu_num) { - LOGP(DSNDCP, LOGL_INFO, "Segment for different SN-PDU " - "(%u != %u)\n", npdu_num, sne->defrag.npdu); - /* FIXME */ - } - - /* FIXME: check if seg_nr already exists */ - /* make sure to subtract length of SNDCP header from 'len' */ - rc = defrag_enqueue(sne, suh->seg_nr, data, len - (data - hdr)); - if (rc < 0) - return rc; - - if (!sch->more) { - /* this is suppsed to be the last segment of the N-PDU, but it - * might well be not the last to arrive */ - sne->defrag.no_more = 1; - } - - if (sne->defrag.no_more) { - /* we have already received the last segment before, let's check - * if all the previous segments exist */ - if (defrag_have_all_segments(sne)) - return defrag_segments(sne); - } - - return 0; -} - -static struct gprs_sndcp_entity *gprs_sndcp_entity_by_lle(const struct gprs_llc_lle *lle, - uint8_t nsapi) -{ - struct gprs_sndcp_entity *sne; - - llist_for_each_entry(sne, &gprs_sndcp_entities, list) { - if (sne->lle == lle && sne->nsapi == nsapi) - return sne; - } - return NULL; -} - -static struct gprs_sndcp_entity *gprs_sndcp_entity_alloc(struct gprs_llc_lle *lle, - uint8_t nsapi) -{ - struct gprs_sndcp_entity *sne; - - sne = talloc_zero(tall_sndcp_ctx, struct gprs_sndcp_entity); - if (!sne) - return NULL; - - sne->lle = lle; - sne->nsapi = nsapi; - sne->defrag.timer.data = sne; - //sne->fqueue.timer.cb = FIXME; - sne->rx_state = SNDCP_RX_S_FIRST; - INIT_LLIST_HEAD(&sne->defrag.frag_list); - - llist_add(&sne->list, &gprs_sndcp_entities); - - return sne; -} - -/* Entry point for the SNSM-ACTIVATE.indication */ -int sndcp_sm_activate_ind(struct gprs_llc_lle *lle, uint8_t nsapi) -{ - LOGP(DSNDCP, LOGL_INFO, "SNSM-ACTIVATE.ind (lle=%p TLLI=%08x, " - "SAPI=%u, NSAPI=%u)\n", lle, lle->llme->tlli, lle->sapi, nsapi); - - if (gprs_sndcp_entity_by_lle(lle, nsapi)) { - LOGP(DSNDCP, LOGL_ERROR, "Trying to ACTIVATE " - "already-existing entity (TLLI=%08x, NSAPI=%u)\n", - lle->llme->tlli, nsapi); - return -EEXIST; - } - - if (!gprs_sndcp_entity_alloc(lle, nsapi)) { - LOGP(DSNDCP, LOGL_ERROR, "Out of memory during ACTIVATE\n"); - return -ENOMEM; - } - - return 0; -} - -/* Entry point for the SNSM-DEACTIVATE.indication */ -int sndcp_sm_deactivate_ind(struct gprs_llc_lle *lle, uint8_t nsapi) -{ - struct gprs_sndcp_entity *sne; - - LOGP(DSNDCP, LOGL_INFO, "SNSM-DEACTIVATE.ind (lle=%p, TLLI=%08x, " - "SAPI=%u, NSAPI=%u)\n", lle, lle->llme->tlli, lle->sapi, nsapi); - - sne = gprs_sndcp_entity_by_lle(lle, nsapi); - if (!sne) { - LOGP(DSNDCP, LOGL_ERROR, "SNSM-DEACTIVATE.ind for non-" - "existing TLLI=%08x SAPI=%u NSAPI=%u\n", lle->llme->tlli, - lle->sapi, nsapi); - return -ENOENT; - } - llist_del(&sne->list); - /* frag queue entries are hierarchically allocated, so no need to - * free them explicitly here */ - talloc_free(sne); - - return 0; -} - -/* Fragmenter state */ -struct sndcp_frag_state { - uint8_t frag_nr; - struct msgb *msg; /* original message */ - uint8_t *next_byte; /* first byte of next fragment */ - - struct gprs_sndcp_entity *sne; - void *mmcontext; -}; - -/* returns '1' if there are more fragments to send, '0' if none */ -static int sndcp_send_ud_frag(struct sndcp_frag_state *fs, - uint8_t pcomp, uint8_t dcomp) -{ - struct gprs_sndcp_entity *sne = fs->sne; - struct gprs_llc_lle *lle = sne->lle; - struct sndcp_common_hdr *sch; - struct sndcp_comp_hdr *scomph; - struct sndcp_udata_hdr *suh; - struct msgb *fmsg; - unsigned int max_payload_len; - unsigned int len; - uint8_t *data; - int rc, more; - - fmsg = msgb_alloc_headroom(fs->sne->lle->params.n201_u+256, 128, - "SNDCP Frag"); - if (!fmsg) { - msgb_free(fs->msg); - return -ENOMEM; - } - - /* make sure lower layers route the fragment like the original */ - msgb_tlli(fmsg) = msgb_tlli(fs->msg); - msgb_bvci(fmsg) = msgb_bvci(fs->msg); - msgb_nsei(fmsg) = msgb_nsei(fs->msg); - - /* prepend common SNDCP header */ - sch = (struct sndcp_common_hdr *) msgb_put(fmsg, sizeof(*sch)); - sch->nsapi = sne->nsapi; - /* Set FIRST bit if we are the first fragment in a series */ - if (fs->frag_nr == 0) - sch->first = 1; - sch->type = 1; - - /* append the compression header for first fragment */ - if (sch->first) { - scomph = (struct sndcp_comp_hdr *) - msgb_put(fmsg, sizeof(*scomph)); - scomph->pcomp = pcomp; - scomph->dcomp = dcomp; - } - - /* append the user-data header */ - suh = (struct sndcp_udata_hdr *) msgb_put(fmsg, sizeof(*suh)); - suh->npdu_low = sne->tx_npdu_nr & 0xff; - suh->npdu_high = (sne->tx_npdu_nr >> 8) & 0xf; - suh->seg_nr = fs->frag_nr % 0xf; - - /* calculate remaining length to be sent */ - len = (fs->msg->data + fs->msg->len) - fs->next_byte; - /* how much payload can we actually send via LLC? */ - max_payload_len = lle->params.n201_u - (sizeof(*sch) + sizeof(*suh)); - if (sch->first) - max_payload_len -= sizeof(*scomph); - /* check if we're exceeding the max */ - if (len > max_payload_len) - len = max_payload_len; - - /* copy the actual fragment data into our fmsg */ - data = msgb_put(fmsg, len); - memcpy(data, fs->next_byte, len); - - /* Increment fragment number and data pointer to next fragment */ - fs->frag_nr++; - fs->next_byte += len; - - /* determine if we have more fragemnts to send */ - if ((fs->msg->data + fs->msg->len) <= fs->next_byte) - more = 0; - else - more = 1; - - /* set the MORE bit of the SNDCP header accordingly */ - sch->more = more; - - rc = gprs_llc_tx_ui(fmsg, lle->sapi, 0, fs->mmcontext, true); - /* abort in case of error, do not advance frag_nr / next_byte */ - if (rc < 0) { - msgb_free(fs->msg); - return rc; - } - - if (!more) { - /* we've sent all fragments */ - msgb_free(fs->msg); - memset(fs, 0, sizeof(*fs)); - /* increment NPDU number for next frame */ - sne->tx_npdu_nr = (sne->tx_npdu_nr + 1) % 0xfff; - return 0; - } - - /* default: more fragments to send */ - return 1; -} - -/* Request transmission of a SN-PDU over specified LLC Entity + SAPI */ -int sndcp_unitdata_req(struct msgb *msg, struct gprs_llc_lle *lle, uint8_t nsapi, - void *mmcontext) -{ - struct gprs_sndcp_entity *sne; - struct sndcp_common_hdr *sch; - struct sndcp_comp_hdr *scomph; - struct sndcp_udata_hdr *suh; - struct sndcp_frag_state fs; - uint8_t pcomp = 0; - uint8_t dcomp = 0; - int rc; - - /* Identifiers from UP: (TLLI, SAPI) + (BVCI, NSEI) */ - - /* Compress packet */ -#if DEBUG_IP_PACKETS == 1 - DEBUGP(DSNDCP, " \n"); - DEBUGP(DSNDCP, ":::::::::::::::::::::::::::::::::::::::::::::::::::\n"); - DEBUGP(DSNDCP, "===================================================\n"); - debug_ip_packet(msg->data, msg->len, 0, "sndcp_initdata_req()"); -#endif - if (any_pcomp_or_dcomp_active(sgsn)) { - - /* Apply header compression */ - rc = gprs_sndcp_pcomp_compress(msg->data, msg->len, &pcomp, - lle->llme->comp.proto, nsapi); - if (rc < 0) { - LOGP(DSNDCP, LOGL_ERROR, - "TCP/IP Header compression failed!\n"); - return -EIO; - } - - /* Fixup pointer locations and sizes in message buffer to match - * the new, compressed buffer size */ - msgb_get(msg, msg->len); - msgb_put(msg, rc); - - /* Apply data compression */ - rc = gprs_sndcp_dcomp_compress(msg->data, msg->len, &dcomp, - lle->llme->comp.data, nsapi); - if (rc < 0) { - LOGP(DSNDCP, LOGL_ERROR, "Data compression failed!\n"); - return -EIO; - } - - /* Fixup pointer locations and sizes in message buffer to match - * the new, compressed buffer size */ - msgb_get(msg, msg->len); - msgb_put(msg, rc); - } -#if DEBUG_IP_PACKETS == 1 - DEBUGP(DSNDCP, "===================================================\n"); - DEBUGP(DSNDCP, ":::::::::::::::::::::::::::::::::::::::::::::::::::\n"); - DEBUGP(DSNDCP, " \n"); -#endif - - sne = gprs_sndcp_entity_by_lle(lle, nsapi); - if (!sne) { - LOGP(DSNDCP, LOGL_ERROR, "Cannot find SNDCP Entity\n"); - msgb_free(msg); - return -EIO; - } - - /* Check if we need to fragment this N-PDU into multiple SN-PDUs */ - if (msg->len > lle->params.n201_u - - (sizeof(*sch) + sizeof(*suh) + sizeof(*scomph))) { - /* initialize the fragmenter state */ - fs.msg = msg; - fs.frag_nr = 0; - fs.next_byte = msg->data; - fs.sne = sne; - fs.mmcontext = mmcontext; - - /* call function to generate and send fragments until all - * of the N-PDU has been sent */ - while (1) { - int rc = sndcp_send_ud_frag(&fs,pcomp,dcomp); - if (rc == 0) - return 0; - if (rc < 0) - return rc; - } - /* not reached */ - return 0; - } - - /* this is the non-fragmenting case where we only build 1 SN-PDU */ - - /* prepend the user-data header */ - suh = (struct sndcp_udata_hdr *) msgb_push(msg, sizeof(*suh)); - suh->npdu_low = sne->tx_npdu_nr & 0xff; - suh->npdu_high = (sne->tx_npdu_nr >> 8) & 0xf; - suh->seg_nr = 0; - sne->tx_npdu_nr = (sne->tx_npdu_nr + 1) % 0xfff; - - scomph = (struct sndcp_comp_hdr *) msgb_push(msg, sizeof(*scomph)); - scomph->pcomp = pcomp; - scomph->dcomp = dcomp; - - /* prepend common SNDCP header */ - sch = (struct sndcp_common_hdr *) msgb_push(msg, sizeof(*sch)); - sch->first = 1; - sch->type = 1; - sch->nsapi = nsapi; - - return gprs_llc_tx_ui(msg, lle->sapi, 0, mmcontext, true); -} - -/* Section 5.1.2.17 LL-UNITDATA.ind */ -int sndcp_llunitdata_ind(struct msgb *msg, struct gprs_llc_lle *lle, - uint8_t *hdr, uint16_t len) -{ - struct gprs_sndcp_entity *sne; - struct sndcp_common_hdr *sch = (struct sndcp_common_hdr *)hdr; - struct sndcp_comp_hdr *scomph = NULL; - struct sndcp_udata_hdr *suh; - uint8_t *npdu; - uint16_t npdu_num __attribute__((unused)); - int npdu_len; - int rc; - uint8_t *expnd = NULL; - - sch = (struct sndcp_common_hdr *) hdr; - if (sch->first) { - scomph = (struct sndcp_comp_hdr *) (hdr + 1); - suh = (struct sndcp_udata_hdr *) (hdr + 1 + sizeof(struct sndcp_common_hdr)); - } else - suh = (struct sndcp_udata_hdr *) (hdr + sizeof(struct sndcp_common_hdr)); - - if (sch->type == 0) { - LOGP(DSNDCP, LOGL_ERROR, "SN-DATA PDU at unitdata_ind() function\n"); - return -EINVAL; - } - - if (len < sizeof(*sch) + sizeof(*suh)) { - LOGP(DSNDCP, LOGL_ERROR, "SN-UNITDATA PDU too short (%u)\n", len); - return -EIO; - } - - sne = gprs_sndcp_entity_by_lle(lle, sch->nsapi); - if (!sne) { - LOGP(DSNDCP, LOGL_ERROR, "Message for non-existing SNDCP Entity " - "(lle=%p, TLLI=%08x, SAPI=%u, NSAPI=%u)\n", lle, - lle->llme->tlli, lle->sapi, sch->nsapi); - return -EIO; - } - /* FIXME: move this RA_ID up to the LLME or even higher */ - bssgp_parse_cell_id(&sne->ra_id, msgb_bcid(msg)); - - if (scomph) { - sne->defrag.pcomp = scomph->pcomp; - sne->defrag.dcomp = scomph->dcomp; - sne->defrag.proto = lle->llme->comp.proto; - sne->defrag.data = lle->llme->comp.data; - } - - /* any non-first segment is by definition something to defragment - * as is any segment that tells us there are more segments */ - if (!sch->first || sch->more) - return defrag_input(sne, msg, hdr, len); - - npdu_num = (suh->npdu_high << 8) | suh->npdu_low; - npdu = (uint8_t *)suh + sizeof(*suh); - npdu_len = (msg->data + msg->len) - npdu - 3; /* -3 'removes' the FCS */ - - if (npdu_len <= 0) { - LOGP(DSNDCP, LOGL_ERROR, "Short SNDCP N-PDU: %d\n", npdu_len); - return -EIO; - } - /* actually send the N-PDU to the SGSN core code, which then - * hands it off to the correct GTP tunnel + GGSN via gtp_data_req() */ - - /* Decompress packet */ -#if DEBUG_IP_PACKETS == 1 - DEBUGP(DSNDCP, " \n"); - DEBUGP(DSNDCP, ":::::::::::::::::::::::::::::::::::::::::::::::::::\n"); - DEBUGP(DSNDCP, "===================================================\n"); -#endif - if (any_pcomp_or_dcomp_active(sgsn)) { - - expnd = talloc_zero_size(msg, npdu_len * MAX_DATADECOMPR_FAC + - MAX_HDRDECOMPR_INCR); - memcpy(expnd, npdu, npdu_len); - - /* Apply data decompression */ - rc = gprs_sndcp_dcomp_expand(expnd, npdu_len, sne->defrag.dcomp, - sne->defrag.data); - if (rc < 0) { - LOGP(DSNDCP, LOGL_ERROR, - "Data decompression failed!\n"); - talloc_free(expnd); - return -EIO; - } - - /* Apply header decompression */ - rc = gprs_sndcp_pcomp_expand(expnd, rc, sne->defrag.pcomp, - sne->defrag.proto); - if (rc < 0) { - LOGP(DSNDCP, LOGL_ERROR, - "TCP/IP Header decompression failed!\n"); - talloc_free(expnd); - return -EIO; - } - - /* Modify npu length, expnd is handed directly handed - * over to gsn_rx_sndcp_ud_ind(), see below */ - npdu_len = rc; - } else - expnd = npdu; -#if DEBUG_IP_PACKETS == 1 - debug_ip_packet(expnd, npdu_len, 1, "sndcp_llunitdata_ind()"); - DEBUGP(DSNDCP, "===================================================\n"); - DEBUGP(DSNDCP, ":::::::::::::::::::::::::::::::::::::::::::::::::::\n"); - DEBUGP(DSNDCP, " \n"); -#endif - - /* Hand off packet to gtp */ - rc = sgsn_rx_sndcp_ud_ind(&sne->ra_id, lle->llme->tlli, - sne->nsapi, msg, npdu_len, expnd); - - if (any_pcomp_or_dcomp_active(sgsn)) - talloc_free(expnd); - - return rc; -} - -#if 0 -/* Section 5.1.2.1 LL-RESET.ind */ -static int sndcp_ll_reset_ind(struct gprs_sndcp_entity *se) -{ - /* treat all outstanding SNDCP-LLC request type primitives as not sent */ - /* reset all SNDCP XID parameters to default values */ - LOGP(DSNDCP, LOGL_NOTICE, "not implemented.\n"); - return 0; -} - -static int sndcp_ll_status_ind() -{ - /* inform the SM sub-layer by means of SNSM-STATUS.req */ - LOGP(DSNDCP, LOGL_NOTICE, "not implemented.\n"); - return 0; -} - -static struct sndcp_state_list {{ - uint32_t states; - unsigned int type; - int (*rout)(struct gprs_sndcp_entity *se, struct msgb *msg); -} sndcp_state_list[] = { - { ALL_STATES, - LL_RESET_IND, sndcp_ll_reset_ind }, - { ALL_STATES, - LL_ESTABLISH_IND, sndcp_ll_est_ind }, - { SBIT(SNDCP_S_EST_RQD), - LL_ESTABLISH_RESP, sndcp_ll_est_ind }, - { SBIT(SNDCP_S_EST_RQD), - LL_ESTABLISH_CONF, sndcp_ll_est_conf }, - { SBIT(SNDCP_S_ -}; - -static int sndcp_rx_llc_prim() -{ - case LL_ESTABLISH_REQ: - case LL_RELEASE_REQ: - case LL_XID_REQ: - case LL_DATA_REQ: - LL_UNITDATA_REQ, /* TLLI, SN-PDU, Ref, QoS, Radio Prio, Ciph */ - - switch (prim) { - case LL_RESET_IND: - case LL_ESTABLISH_IND: - case LL_ESTABLISH_RESP: - case LL_ESTABLISH_CONF: - case LL_RELEASE_IND: - case LL_RELEASE_CONF: - case LL_XID_IND: - case LL_XID_RESP: - case LL_XID_CONF: - case LL_DATA_IND: - case LL_DATA_CONF: - case LL_UNITDATA_IND: - case LL_STATUS_IND: - } -} -#endif - -/* Generate SNDCP-XID message */ -static int gprs_llc_gen_sndcp_xid(uint8_t *bytes, int bytes_len, uint8_t nsapi) -{ - int entity = 0; - LLIST_HEAD(comp_fields); - struct gprs_sndcp_pcomp_rfc1144_params rfc1144_params; - struct gprs_sndcp_comp_field rfc1144_comp_field; - struct gprs_sndcp_dcomp_v42bis_params v42bis_params; - struct gprs_sndcp_comp_field v42bis_comp_field; - - memset(&rfc1144_comp_field, 0, sizeof(struct gprs_sndcp_comp_field)); - memset(&v42bis_comp_field, 0, sizeof(struct gprs_sndcp_comp_field)); - - /* Setup rfc1144 */ - if (sgsn->cfg.pcomp_rfc1144.active) { - rfc1144_params.nsapi[0] = nsapi; - rfc1144_params.nsapi_len = 1; - rfc1144_params.s01 = sgsn->cfg.pcomp_rfc1144.s01; - rfc1144_comp_field.p = 1; - rfc1144_comp_field.entity = entity; - rfc1144_comp_field.algo = RFC_1144; - rfc1144_comp_field.comp[RFC1144_PCOMP1] = 1; - rfc1144_comp_field.comp[RFC1144_PCOMP2] = 2; - rfc1144_comp_field.comp_len = RFC1144_PCOMP_NUM; - rfc1144_comp_field.rfc1144_params = &rfc1144_params; - entity++; - llist_add(&rfc1144_comp_field.list, &comp_fields); - } - - /* Setup V.42bis */ - if (sgsn->cfg.dcomp_v42bis.active) { - v42bis_params.nsapi[0] = nsapi; - v42bis_params.nsapi_len = 1; - v42bis_params.p0 = sgsn->cfg.dcomp_v42bis.p0; - v42bis_params.p1 = sgsn->cfg.dcomp_v42bis.p1; - v42bis_params.p2 = sgsn->cfg.dcomp_v42bis.p2; - v42bis_comp_field.p = 1; - v42bis_comp_field.entity = entity; - v42bis_comp_field.algo = V42BIS; - v42bis_comp_field.comp[V42BIS_DCOMP1] = 1; - v42bis_comp_field.comp_len = V42BIS_DCOMP_NUM; - v42bis_comp_field.v42bis_params = &v42bis_params; - entity++; - llist_add(&v42bis_comp_field.list, &comp_fields); - } - - /* Do not attempt to compile anything if there is no data in the list */ - if (llist_empty(&comp_fields)) - return 0; - - /* Compile bytestream */ - return gprs_sndcp_compile_xid(bytes, bytes_len, &comp_fields, - DEFAULT_SNDCP_VERSION); -} - -/* Set of SNDCP-XID bnegotiation (See also: TS 144 065, - * Section 6.8 XID parameter negotiation) */ -int sndcp_sn_xid_req(struct gprs_llc_lle *lle, uint8_t nsapi) -{ - /* Note: The specification requires the SNDCP-User to set of an - * SNDCP xid request. See also 3GPP TS 44.065, 6.8 XID parameter - * negotiation, Figure 11: SNDCP XID negotiation procedure. In - * our case the SNDCP-User is sgsn_libgtp.c, which calls - * sndcp_sn_xid_req directly. */ - - uint8_t l3params[1024]; - int xid_len; - struct gprs_llc_xid_field xid_field_request; - - /* Wipe off all compression entities and their states to - * get rid of possible leftovers from a previous session */ - gprs_sndcp_comp_free(lle->llme->comp.proto); - gprs_sndcp_comp_free(lle->llme->comp.data); - lle->llme->comp.proto = gprs_sndcp_comp_alloc(lle->llme); - lle->llme->comp.data = gprs_sndcp_comp_alloc(lle->llme); - talloc_free(lle->llme->xid); - lle->llme->xid = NULL; - - /* Generate compression parameter bytestream */ - xid_len = gprs_llc_gen_sndcp_xid(l3params, sizeof(l3params), nsapi); - - /* Send XID with the SNDCP-XID bytetsream included */ - if (xid_len > 0) { - xid_field_request.type = GPRS_LLC_XID_T_L3_PAR; - xid_field_request.data = l3params; - xid_field_request.data_len = xid_len; - return gprs_ll_xid_req(lle, &xid_field_request); - } - - /* When bytestream can not be generated, proceed without SNDCP-XID */ - return gprs_ll_xid_req(lle, NULL); - -} - -/* Handle header compression entites */ -static int handle_pcomp_entities(struct gprs_sndcp_comp_field *comp_field, - struct gprs_llc_lle *lle) -{ - /* Note: This functions also transforms the comp_field into its - * echo form (strips comp values, resets propose bit etc...) - * the processed comp_fields can then be sent back as XID- - * Response without further modification. */ - - /* Delete propose bit */ - comp_field->p = 0; - - /* Process proposed parameters */ - switch (comp_field->algo) { - case RFC_1144: - if (sgsn->cfg.pcomp_rfc1144.passive - && comp_field->rfc1144_params->nsapi_len > 0) { - DEBUGP(DSNDCP, - "Accepting RFC1144 header compression...\n"); - gprs_sndcp_comp_add(lle->llme, lle->llme->comp.proto, - comp_field); - } else { - DEBUGP(DSNDCP, - "Rejecting RFC1144 header compression...\n"); - gprs_sndcp_comp_delete(lle->llme->comp.proto, - comp_field->entity); - comp_field->rfc1144_params->nsapi_len = 0; - } - break; - case RFC_2507: - /* RFC 2507 is not yet supported, - * so we set applicable nsapis to zero */ - DEBUGP(DSNDCP, "Rejecting RFC2507 header compression...\n"); - comp_field->rfc2507_params->nsapi_len = 0; - gprs_sndcp_comp_delete(lle->llme->comp.proto, - comp_field->entity); - break; - case ROHC: - /* ROHC is not yet supported, - * so we set applicable nsapis to zero */ - DEBUGP(DSNDCP, "Rejecting ROHC header compression...\n"); - comp_field->rohc_params->nsapi_len = 0; - gprs_sndcp_comp_delete(lle->llme->comp.proto, - comp_field->entity); - break; - } - - return 0; -} - -/* Hanle data compression entites */ -static int handle_dcomp_entities(struct gprs_sndcp_comp_field *comp_field, - struct gprs_llc_lle *lle) -{ - /* See note in handle_pcomp_entities() */ - - /* Delete propose bit */ - comp_field->p = 0; - - /* Process proposed parameters */ - switch (comp_field->algo) { - case V42BIS: - if (sgsn->cfg.dcomp_v42bis.passive && - comp_field->v42bis_params->nsapi_len > 0) { - DEBUGP(DSNDCP, - "Accepting V.42bis data compression...\n"); - gprs_sndcp_comp_add(lle->llme, lle->llme->comp.data, - comp_field); - } else { - LOGP(DSNDCP, LOGL_DEBUG, - "Rejecting V.42bis data compression...\n"); - gprs_sndcp_comp_delete(lle->llme->comp.data, - comp_field->entity); - comp_field->v42bis_params->nsapi_len = 0; - } - break; - case V44: - /* V44 is not yet supported, - * so we set applicable nsapis to zero */ - DEBUGP(DSNDCP, "Rejecting V.44 data compression...\n"); - comp_field->v44_params->nsapi_len = 0; - gprs_sndcp_comp_delete(lle->llme->comp.data, - comp_field->entity); - break; - } - - return 0; - -} - -/* Process SNDCP-XID indication - * (See also: TS 144 065, Section 6.8 XID parameter negotiation) */ -int sndcp_sn_xid_ind(struct gprs_llc_xid_field *xid_field_indication, - struct gprs_llc_xid_field *xid_field_response, - struct gprs_llc_lle *lle) -{ - /* Note: This function computes the SNDCP-XID response that is sent - * back to the ms when a ms originated XID is received. The - * Input XID fields are directly processed and the result is directly - * handed back. */ - - int rc; - int compclass; - int version; - - struct llist_head *comp_fields; - struct gprs_sndcp_comp_field *comp_field; - - OSMO_ASSERT(xid_field_indication); - OSMO_ASSERT(xid_field_response); - OSMO_ASSERT(lle); - - /* Parse SNDCP-CID XID-Field */ - comp_fields = gprs_sndcp_parse_xid(&version, lle->llme, - xid_field_indication->data, - xid_field_indication->data_len, - NULL); - if (!comp_fields) - return -EINVAL; - - /* Handle compression entites */ - DEBUGP(DSNDCP, "SNDCP-XID-IND (ms):\n"); - gprs_sndcp_dump_comp_fields(comp_fields, LOGL_DEBUG); - - llist_for_each_entry(comp_field, comp_fields, list) { - compclass = gprs_sndcp_get_compression_class(comp_field); - if (compclass == SNDCP_XID_PROTOCOL_COMPRESSION) - rc = handle_pcomp_entities(comp_field, lle); - else if (compclass == SNDCP_XID_DATA_COMPRESSION) - rc = handle_dcomp_entities(comp_field, lle); - else { - gprs_sndcp_comp_delete(lle->llme->comp.proto, - comp_field->entity); - gprs_sndcp_comp_delete(lle->llme->comp.data, - comp_field->entity); - rc = 0; - } - - if (rc < 0) { - talloc_free(comp_fields); - return -EINVAL; - } - } - - DEBUGP(DSNDCP, "SNDCP-XID-RES (sgsn):\n"); - gprs_sndcp_dump_comp_fields(comp_fields, LOGL_DEBUG); - - /* Reserve some memory to store the modified SNDCP-XID bytes */ - xid_field_response->data = - talloc_zero_size(lle->llme, xid_field_indication->data_len); - - /* Set Type flag for response */ - xid_field_response->type = GPRS_LLC_XID_T_L3_PAR; - - /* Compile modified SNDCP-XID bytes */ - rc = gprs_sndcp_compile_xid(xid_field_response->data, - xid_field_indication->data_len, - comp_fields, 0); - - if (rc > 0) - xid_field_response->data_len = rc; - else { - talloc_free(xid_field_response->data); - xid_field_response->data = NULL; - xid_field_response->data_len = 0; - return -EINVAL; - } - - talloc_free(comp_fields); - - return 0; -} - -/* Process SNDCP-XID indication - * (See also: TS 144 065, Section 6.8 XID parameter negotiation) */ -int sndcp_sn_xid_conf(struct gprs_llc_xid_field *xid_field_conf, - struct gprs_llc_xid_field *xid_field_request, - struct gprs_llc_lle *lle) -{ - /* Note: This function handles an incomming SNDCP-XID confirmiation. - * Since the confirmation fields may lack important parameters we - * will reconstruct these missing fields using the original request - * we have sent. After that we will create (or delete) the - * compression entites */ - - struct llist_head *comp_fields_req; - struct llist_head *comp_fields_conf; - struct gprs_sndcp_comp_field *comp_field; - int rc; - int compclass; - - /* We need both, the confirmation that is sent back by the ms, - * and the original request we have sent. If one of this is missing - * we can not process the confirmation, the caller must check if - * request and confirmation fields are available. */ - OSMO_ASSERT(xid_field_conf); - OSMO_ASSERT(xid_field_request); - - /* Parse SNDCP-CID XID-Field */ - comp_fields_req = gprs_sndcp_parse_xid(NULL, lle->llme, - xid_field_request->data, - xid_field_request->data_len, - NULL); - if (!comp_fields_req) - return -EINVAL; - - DEBUGP(DSNDCP, "SNDCP-XID-REQ (sgsn):\n"); - gprs_sndcp_dump_comp_fields(comp_fields_req, LOGL_DEBUG); - - /* Parse SNDCP-CID XID-Field */ - comp_fields_conf = gprs_sndcp_parse_xid(NULL, lle->llme, - xid_field_conf->data, - xid_field_conf->data_len, - comp_fields_req); - if (!comp_fields_conf) - return -EINVAL; - - DEBUGP(DSNDCP, "SNDCP-XID-CONF (ms):\n"); - gprs_sndcp_dump_comp_fields(comp_fields_conf, LOGL_DEBUG); - - /* Handle compression entites */ - llist_for_each_entry(comp_field, comp_fields_conf, list) { - compclass = gprs_sndcp_get_compression_class(comp_field); - if (compclass == SNDCP_XID_PROTOCOL_COMPRESSION) - rc = handle_pcomp_entities(comp_field, lle); - else if (compclass == SNDCP_XID_DATA_COMPRESSION) - rc = handle_dcomp_entities(comp_field, lle); - else { - gprs_sndcp_comp_delete(lle->llme->comp.proto, - comp_field->entity); - gprs_sndcp_comp_delete(lle->llme->comp.data, - comp_field->entity); - rc = 0; - } - - if (rc < 0) { - talloc_free(comp_fields_req); - talloc_free(comp_fields_conf); - return -EINVAL; - } - } - - talloc_free(comp_fields_req); - talloc_free(comp_fields_conf); - - return 0; -} |