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-rw-r--r--openbsc/src/libtrau/trau_mux.c307
1 files changed, 249 insertions, 58 deletions
diff --git a/openbsc/src/libtrau/trau_mux.c b/openbsc/src/libtrau/trau_mux.c
index 9272ac04f..c9d77cf78 100644
--- a/openbsc/src/libtrau/trau_mux.c
+++ b/openbsc/src/libtrau/trau_mux.c
@@ -30,6 +30,7 @@
#include <openbsc/debug.h>
#include <osmocom/core/talloc.h>
#include <openbsc/trau_upqueue.h>
+#include <osmocom/core/crcgen.h>
/* this corresponds to the bit-lengths of the individual codec
* parameters as indicated in Table 1.1 of TS 06.10 */
@@ -46,6 +47,53 @@ static const uint8_t gsm_fr_map[] = {
3, 3, 3, 3
};
+
+/*
+ * EFR TRAU parity
+ *
+ * g(x) = x^3 + x^1 + 1
+ */
+static const struct osmo_crc8gen_code gsm0860_efr_crc3 = {
+ .bits = 3,
+ .poly = 0x3,
+ .init = 0x0,
+ .remainder = 0x7,
+};
+
+/* EFR parity bits */
+static inline void efr_parity_bits_1(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 0, 22);
+ memcpy(check_bits + 22 , d_bits + 24, 3);
+ check_bits[25] = d_bits[28];
+}
+
+static inline void efr_parity_bits_2(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 42, 10);
+ memcpy(check_bits + 10 , d_bits + 90, 2);
+}
+
+static inline void efr_parity_bits_3(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 98, 5);
+ check_bits[5] = d_bits[104];
+ memcpy(check_bits + 6 , d_bits + 143, 2);
+}
+
+static inline void efr_parity_bits_4(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 151, 10);
+ memcpy(check_bits + 10 , d_bits + 199, 2);
+}
+
+static inline void efr_parity_bits_5(ubit_t *check_bits, const ubit_t *d_bits)
+{
+ memcpy(check_bits + 0 , d_bits + 207, 5);
+ check_bits[5] = d_bits[213];
+ memcpy(check_bits + 6 , d_bits + 252, 2);
+}
+
struct map_entry {
struct llist_head list;
struct gsm_e1_subslot src, dst;
@@ -158,7 +206,117 @@ lookup_trau_upqueue(const struct gsm_e1_subslot *src)
return NULL;
}
-static const uint8_t c_bits_check[] = { 0, 0, 0, 1, 0 };
+static const uint8_t c_bits_check_fr[] = { 0, 0, 0, 1, 0 };
+static const uint8_t c_bits_check_efr[] = { 1, 1, 0, 1, 0 };
+
+struct msgb *trau_decode_fr(uint32_t callref,
+ const struct decoded_trau_frame *tf)
+{
+ struct msgb *msg;
+ struct gsm_data_frame *frame;
+ unsigned char *data;
+ int i, j, k, l, o;
+
+ msg = msgb_alloc(sizeof(struct gsm_data_frame) + 33,
+ "GSM-DATA");
+ if (!msg)
+ return NULL;
+
+ 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 = callref;
+ msgb_put(msg, sizeof(struct gsm_data_frame) + 33);
+
+ return msg;
+}
+
+struct msgb *trau_decode_efr(uint32_t callref,
+ const struct decoded_trau_frame *tf)
+{
+ struct msgb *msg;
+ struct gsm_data_frame *frame;
+ unsigned char *data;
+ int i, j, rc;
+ ubit_t check_bits[26];
+
+ msg = msgb_alloc(sizeof(struct gsm_data_frame) + 31,
+ "GSM-DATA");
+ if (!msg)
+ return NULL;
+
+ frame = (struct gsm_data_frame *)msg->data;
+ memset(frame, 0, sizeof(struct gsm_data_frame));
+ frame->msg_type = GSM_TCHF_FRAME_EFR;
+ frame->callref = callref;
+ msgb_put(msg, sizeof(struct gsm_data_frame) + 31);
+
+ if (tf->c_bits[11]) /* BFI */
+ goto bad_frame;
+
+ data = frame->data;
+ data[0] = 0xc << 4;
+ /* reassemble d-bits */
+ for (i = 1, j = 4; i < 39; i++, j++)
+ data[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_1(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 26,
+ tf->d_bits + 39);
+ if (rc)
+ goto bad_frame;
+ for (i = 42, j = 42; i < 95; i++, j++)
+ data[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_2(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 12,
+ tf->d_bits + 95);
+ if (rc)
+ goto bad_frame;
+ for (i = 98, j = 95; i < 148; i++, j++)
+ data[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_3(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 8,
+ tf->d_bits + 148);
+ if (rc)
+ goto bad_frame;
+ for (i = 151, j = 145; i < 204; i++, j++)
+ data[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_4(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 12,
+ tf->d_bits + 204);
+ if (rc)
+ goto bad_frame;
+ for (i = 207, j = 198; i < 257; i++, j++)
+ data[j/8] |= (tf->d_bits[i] << (7-(j%8)));
+ efr_parity_bits_5(check_bits, tf->d_bits);
+ rc = osmo_crc8gen_check_bits(&gsm0860_efr_crc3, check_bits, 8,
+ tf->d_bits + 257);
+ if (rc)
+ goto bad_frame;
+
+ return msg;
+
+bad_frame:
+ frame->msg_type = GSM_TCHF_BAD_FRAME;
+
+ return msg;
+}
/* we get called by subchan_demux */
int trau_mux_input(struct gsm_e1_subslot *src_e1_ss,
@@ -177,45 +335,25 @@ 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;
+ struct msgb *msg = NULL;
/* frame shall be sent to upqueue */
if (!(ue = lookup_trau_upqueue(src_e1_ss)))
return -EINVAL;
if (!ue->callref)
return -EINVAL;
- if (memcmp(tf.c_bits, c_bits_check, sizeof(c_bits_check)))
+ if (!memcmp(tf.c_bits, c_bits_check_fr, 5))
+ msg = trau_decode_fr(ue->callref, &tf);
+ else if (!memcmp(tf.c_bits, c_bits_check_efr, 5))
+ msg = trau_decode_efr(ue->callref, &tf);
+ else {
DEBUGPC(DLMUX, "illegal trau (C1-C5) %s\n",
- osmo_hexdump(tf.c_bits, sizeof(c_bits_check)));
- msg = msgb_alloc(sizeof(struct gsm_data_frame) + 33,
- "GSM-DATA");
+ osmo_hexdump(tf.c_bits, 5));
+ DEBUGPC(DLMUX, "test trau (C1-C5) %s\n",
+ osmo_hexdump(c_bits_check_efr, 5));
+ return -EINVAL;
+ }
if (!msg)
return -ENOMEM;
-
- 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;
- msgb_put(msg, sizeof(struct gsm_data_frame) + 33);
trau_tx_to_mncc(ue->net, msg);
return 0;
@@ -275,13 +413,86 @@ int trau_recv_lchan(struct gsm_lchan *lchan, uint32_t callref)
return 0;
}
+void trau_encode_fr(struct decoded_trau_frame *tf,
+ const unsigned char *data)
+{
+ int i, j, k, l, o;
+
+ /* 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++;
+ }
+}
+
+void trau_encode_efr(struct decoded_trau_frame *tf,
+ const unsigned char *data)
+{
+ int i, j;
+ ubit_t check_bits[26];
+
+ /* set c-bits and t-bits */
+ tf->c_bits[0] = 1;
+ tf->c_bits[1] = 1;
+ tf->c_bits[2] = 0;
+ tf->c_bits[3] = 1;
+ 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 */
+ tf->d_bits[0] = 1;
+ for (i = 1, j = 4; i < 39; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_1(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 26,
+ tf->d_bits + 39);
+ for (i = 42, j = 42; i < 95; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_2(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 12,
+ tf->d_bits + 95);
+ for (i = 98, j = 95; i < 148; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_3(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 8,
+ tf->d_bits + 148);
+ for (i = 151, j = 145; i < 204; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_4(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 12,
+ tf->d_bits + 204);
+ for (i = 207, j = 198; i < 257; i++, j++)
+ tf->d_bits[i] = (data[j/8] >> (7-(j%8))) & 1;
+ efr_parity_bits_5(check_bits, tf->d_bits);
+ osmo_crc8gen_set_bits(&gsm0860_efr_crc3, check_bits, 8,
+ tf->d_bits + 257);
+}
+
int trau_send_frame(struct gsm_lchan *lchan, struct gsm_data_frame *frame)
{
uint8_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);
@@ -290,30 +501,10 @@ int trau_send_frame(struct gsm_lchan *lchan, struct gsm_data_frame *frame)
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++;
- }
+ trau_encode_fr(&tf, frame->data);
+ break;
+ case GSM_TCHF_FRAME_EFR:
+ trau_encode_efr(&tf, frame->data);
break;
default:
DEBUGPC(DLMUX, "unsupported message type %d\n",
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-24 22:25:06 +0000