diff options
Diffstat (limited to 'openbsc/src/trau_mux.c')
-rw-r--r-- | openbsc/src/trau_mux.c | 92 |
1 files changed, 83 insertions, 9 deletions
diff --git a/openbsc/src/trau_mux.c b/openbsc/src/trau_mux.c index 7ea65ce35..477ea21e5 100644 --- a/openbsc/src/trau_mux.c +++ b/openbsc/src/trau_mux.c @@ -32,6 +32,19 @@ #include <openbsc/debug.h> #include <openbsc/talloc.h> +u_int8_t gsm_fr_map[] = { + 6, 6, 5, 5, 4, 4, 3, 3, + 7, 2, 2, 6, 3, 3, 3, 3, + 3, 3, 3, 3, 3, 3, 3, 3, + 3, 7, 2, 2, 6, 3, 3, 3, + 3, 3, 3, 3, 3, 3, 3, 3, + 3, 3, 7, 2, 2, 6, 3, 3, + 3, 3, 3, 3, 3, 3, 3, 3, + 3, 3, 3, 7, 2, 2, 6, 3, + 3, 3, 3, 3, 3, 3, 3, 3, + 3, 3, 3, 3 +}; + struct map_entry { struct llist_head list; struct gsm_e1_subslot src, dst; @@ -144,6 +157,8 @@ lookup_trau_upqueue(const struct gsm_e1_subslot *src) return NULL; } +static const u_int8_t c_bits_check[] = { 0, 0, 0, 1, 0 }; + /* we get called by subchan_demux */ int trau_mux_input(struct gsm_e1_subslot *src_e1_ss, const u_int8_t *trau_bits, int num_bits) @@ -153,8 +168,6 @@ int trau_mux_input(struct gsm_e1_subslot *src_e1_ss, struct gsm_e1_subslot *dst_e1_ss = lookup_trau_mux_map(src_e1_ss); struct subch_mux *mx; struct upqueue_entry *ue; - struct msgb *msg; - struct gsm_trau_frame *frame; int rc; /* decode TRAU, change it to downlink, re-encode */ @@ -163,19 +176,44 @@ int trau_mux_input(struct gsm_e1_subslot *src_e1_ss, return rc; if (!dst_e1_ss) { + struct msgb *msg; + struct gsm_data_frame *frame; + unsigned char *data; + int i, j, k, l, o; /* frame shall be sent to upqueue */ if (!(ue = lookup_trau_upqueue(src_e1_ss))) return -EINVAL; if (!ue->callref) return -EINVAL; - msg = msgb_alloc(sizeof(struct gsm_trau_frame) + sizeof(tf), - "TRAU"); + if (memcpy(tf.c_bits, c_bits_check, sizeof(c_bits_check))) + DEBUGPC(DMUX, "illegal trau (C1-C5) %s\n", + hexdump(tf.c_bits, sizeof(c_bits_check))); + msg = msgb_alloc(sizeof(struct gsm_data_frame) + 33, + "GSM-DATA"); if (!msg) return -ENOMEM; - frame = (struct gsm_trau_frame *)msg->data; - frame->msg_type = GSM_TRAU_FRAME; + + frame = (struct gsm_data_frame *)msg->data; + memset(frame, 0, sizeof(struct gsm_data_frame)); + data = frame->data; + data[0] = 0xd << 4; + /* reassemble d-bits */ + i = 0; /* counts bits */ + j = 4; /* counts output bits */ + k = gsm_fr_map[0]-1; /* current number bit in element */ + l = 0; /* counts element bits */ + o = 0; /* offset input bits */ + while (i < 260) { + data[j/8] |= (tf.d_bits[k+o] << (7-(j%8))); + if (--k < 0) { + o += gsm_fr_map[l]; + k = gsm_fr_map[++l]-1; + } + i++; + j++; + } + frame->msg_type = GSM_TCHF_FRAME; frame->callref = ue->callref; - memcpy(frame->data, &tf, sizeof(tf)); msgb_enqueue(&ue->net->upqueue, msg); return 0; @@ -221,17 +259,53 @@ int trau_recv_lchan(struct gsm_lchan *lchan, u_int32_t callref) return 0; } -int trau_send_lchan(struct gsm_lchan *lchan, struct decoded_trau_frame *tf) +int trau_send_frame(struct gsm_lchan *lchan, struct gsm_data_frame *frame) { u_int8_t trau_bits_out[TRAU_FRAME_BITS]; struct gsm_e1_subslot *dst_e1_ss = &lchan->ts->e1_link; struct subch_mux *mx; + int i, j, k, l, o; + unsigned char *data = frame->data; + struct decoded_trau_frame tf; mx = e1inp_get_mux(dst_e1_ss->e1_nr, dst_e1_ss->e1_ts); if (!mx) return -EINVAL; - encode_trau_frame(trau_bits_out, tf); + switch (frame->msg_type) { + case GSM_TCHF_FRAME: + /* set c-bits and t-bits */ + tf.c_bits[0] = 1; + tf.c_bits[1] = 1; + tf.c_bits[2] = 1; + tf.c_bits[3] = 0; + tf.c_bits[4] = 0; + memset(&tf.c_bits[5], 0, 6); + memset(&tf.c_bits[11], 1, 10); + memset(&tf.t_bits[0], 1, 4); + /* reassemble d-bits */ + i = 0; /* counts bits */ + j = 4; /* counts input bits */ + k = gsm_fr_map[0]-1; /* current number bit in element */ + l = 0; /* counts element bits */ + o = 0; /* offset output bits */ + while (i < 260) { + tf.d_bits[k+o] = (data[j/8] >> (7-(j%8))) & 1; + if (--k < 0) { + o += gsm_fr_map[l]; + k = gsm_fr_map[++l]-1; + } + i++; + j++; + } + break; + default: + DEBUGPC(DMUX, "unsupported message type %d\n", + frame->msg_type); + return -EINVAL; + } + + encode_trau_frame(trau_bits_out, &tf); /* and send it to the muxer */ return subchan_mux_enqueue(mx, dst_e1_ss->e1_ts_ss, trau_bits_out, |