From a42563b684f98e82f29c764e97b5f5467eb3f213 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Sat, 7 Mar 2020 20:30:01 +0100 Subject: virt_phy: implement GSMTAP_CHANNEL_VOICE GSMTAP_CHANNEL_VOICE is the mechanism by which GSMTAP can [finally!] be used to transport circuit-switched voice codec payload, and not just signalling. Original patch by Neels Hofmeyr, heavily extended by Harald Welte. Change-Id: Id72cf23b7c6587efae4cdaa7b50ab4d85b8c8d22 --- src/host/virt_phy/configure.ac | 2 ++ src/host/virt_phy/src/gsmtapl1_if.c | 59 ++++++++++++++++++++++++++----- src/host/virt_phy/src/virt_prim_traffic.c | 16 ++++++--- 3 files changed, 63 insertions(+), 14 deletions(-) diff --git a/src/host/virt_phy/configure.ac b/src/host/virt_phy/configure.ac index a2c2bf65..fbff2c11 100644 --- a/src/host/virt_phy/configure.ac +++ b/src/host/virt_phy/configure.ac @@ -12,6 +12,8 @@ AC_PROG_CC AC_PROG_INSTALL dnl checks for libraries +dnl TODO: insert libosmocore version with GSMTAP_CHANNEL_VOICE: PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore >= 1.4.0) +dnl (at time of writing not released yet) PKG_CHECK_MODULES(LIBOSMOCORE, libosmocore) PKG_CHECK_MODULES(LIBOSMOGSM, libosmogsm) diff --git a/src/host/virt_phy/src/gsmtapl1_if.c b/src/host/virt_phy/src/gsmtapl1_if.c index 30f88ff4..3fa69c4f 100644 --- a/src/host/virt_phy/src/gsmtapl1_if.c +++ b/src/host/virt_phy/src/gsmtapl1_if.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -48,6 +49,29 @@ static char *pseudo_lchan_name(uint16_t arfcn, uint8_t ts, uint8_t ss, uint8_t s return lname; } +/* Return gsmtap_um_voice_type or -1 on error */ +static int get_um_voice_type(enum gsm48_chan_mode tch_mode, uint8_t rsl_chantype) +{ + switch (tch_mode) { + case GSM48_CMODE_SPEECH_V1: + switch (rsl_chantype) { + case RSL_CHAN_Bm_ACCHs: + return GSMTAP_UM_VOICE_FR; + case RSL_CHAN_Lm_ACCHs: + return GSMTAP_UM_VOICE_HR; + default: + return -1; + } + break; + case GSM48_CMODE_SPEECH_EFR: + return GSMTAP_UM_VOICE_EFR; + case GSM48_CMODE_SPEECH_AMR: + return GSMTAP_UM_VOICE_AMR; + default: + return -1; + } +} + /** * Replace l11 header of given msgb by a gsmtap header and send it over the virt um. */ @@ -74,12 +98,25 @@ void gsmtapl1_tx_to_virt_um_inst(struct l1_model_ms *ms, uint32_t fn, uint8_t tn rsl_chantype = RSL_CHAN_OSMO_PDCH; timeslot = tn; subslot = 0; - gsmtap_chan = chantype_rsl2gsmtap(rsl_chantype, 0); + gsmtap_chan = chantype_rsl2gsmtap2(rsl_chantype, 0, false); + break; + case L1CTL_TRAFFIC_REQ: + ul = (struct l1ctl_info_ul *)l1h->data; + rsl_dec_chan_nr(ul->chan_nr, &rsl_chantype, &subslot, ×lot); + gsmtap_chan = chantype_rsl2gsmtap2(rsl_chantype, 0, true); + /* the first byte indicates the type of voice codec (gsmtap_um_voice_type); + * let's first strip any data in front of the l2 header, then push this extra + * byte to the front and finally adjust the l2h pointer */ + msgb_pull_to_l2(msg); + msgb_push_u8(msg, get_um_voice_type(ms->state.tch_mode, rsl_chantype)); + msg->l2h = msg->data; + data = msgb_l2(msg); + data_len = msgb_l2len(msg); break; default: ul = (struct l1ctl_info_ul *)l1h->data; rsl_dec_chan_nr(ul->chan_nr, &rsl_chantype, &subslot, ×lot); - gsmtap_chan = chantype_rsl2gsmtap(rsl_chantype, ul->link_id); + gsmtap_chan = chantype_rsl2gsmtap2(rsl_chantype, ul->link_id, false); break; } @@ -219,13 +256,7 @@ static void l1ctl_from_virt_um(struct l1ctl_sock_client *lsc, struct msgb *msg, switch (gsmtap_chantype & ~GSMTAP_CHANNEL_ACCH & 0xff) { case GSMTAP_CHANNEL_TCH_H: case GSMTAP_CHANNEL_TCH_F: -#if 0 - /* TODO: handle voice */ - if (!facch && !tch_acch) { - l1ctl_tx_traffic_ind(msg, arfcn, link_id, chan_nr, fn, - snr, signal_dbm, 0, 0); - } -#endif + /* This is TCH signalling, for voice frames see GSMTAP_CHANNEL_VOICE */ case GSMTAP_CHANNEL_SDCCH4: case GSMTAP_CHANNEL_SDCCH8: /* only forward messages on dedicated channels to l2, if @@ -235,6 +266,16 @@ static void l1ctl_from_virt_um(struct l1ctl_sock_client *lsc, struct msgb *msg, l1ctl_tx_data_ind(ms, msg, arfcn, link_id, chan_nr, fn, snr_db, signal_dbm, 0, 0); } break; + case GSMTAP_CHANNEL_VOICE_F: + case GSMTAP_CHANNEL_VOICE_H: + /* only forward messages on dedicated channels to l2, if + * the timeslot and subslot is fitting */ + if (ms->state.dedicated.tn == timeslot + && ms->state.dedicated.subslot == subslot) { + l1ctl_tx_traffic_ind(ms, msg, arfcn, link_id, chan_nr, fn, + snr_db, signal_dbm, 0, 0); + } + break; case GSMTAP_CHANNEL_CBCH51: /* only pass CBCH data if the user application actually indicated that a CBCH * is present */ diff --git a/src/host/virt_phy/src/virt_prim_traffic.c b/src/host/virt_phy/src/virt_prim_traffic.c index 5f6b273b..3d2b2b15 100644 --- a/src/host/virt_phy/src/virt_prim_traffic.c +++ b/src/host/virt_phy/src/virt_prim_traffic.c @@ -84,7 +84,8 @@ void l1ctl_tx_traffic_ind(struct l1_model_ms *ms, struct msgb *msg, uint16_t arf struct msgb *l1ctl_msg = NULL; struct l1ctl_traffic_ind * l1ti; struct l1ctl_info_dl * l1dl; - uint8_t *frame, frame_len; + uint8_t *frame; + int frame_len; uint8_t rsl_chan_type, subchan, timeslot; l1ctl_msg = l1ctl_msgb_alloc(L1CTL_TRAFFIC_IND); l1dl = (struct l1ctl_info_dl *) msgb_put(l1ctl_msg, sizeof(*l1dl)); @@ -101,11 +102,16 @@ void l1ctl_tx_traffic_ind(struct l1_model_ms *ms, struct msgb *msg, uint16_t arf l1dl->num_biterr = 0; /* no biterrors */ l1dl->fire_crc = 0; - /* TODO: traffic decoding and decryption */ - - frame_len = msgb_length(msg); + /* The first byte indicates the type of voice frame (enum gsmtap_um_voice_type), + * which we simply ignore here and pass on the frame without that byte. + * TODO: Check for consistency with ms->state.tch_mode ? */ + frame_len = msgb_length(msg) - 1; + if (frame_len < 0) { + msgb_free(l1ctl_msg); + return; + } frame = (uint8_t *) msgb_put(l1ctl_msg, frame_len); - memcpy(frame, msgb_data(msg), frame_len); + memcpy(frame, msgb_data(msg)+1, frame_len); DEBUGPMS(DL1P, ms, "Tx L1CTL_TRAFFIC_IND (chan_nr=0x%02x, link_id=0x%02x)\n", chan_nr, link_id); l1ctl_sap_tx_to_l23_inst(ms, l1ctl_msg); -- cgit v1.2.3