From e0c65301d5786be04cf4731f1cdeed05c4442482 Mon Sep 17 00:00:00 2001 From: Philipp Maier Date: Tue, 28 Mar 2017 17:05:40 +0200 Subject: gsm0808: Add utils for Channel Type The planned support for true A over IP requires the encoding of the a Channel Type element (see also ASSIGNMENT REQUEST). This commt adds encoding/decoding functionality and tests for the element mentioned above, however, it is not yet actively used. Change-Id: Id0e2164d84b8cbcc6fe6a090fc7f40a1251421d7 --- include/osmocom/gsm/gsm0808_utils.h | 8 ++++ include/osmocom/gsm/protocol/gsm_08_08.h | 9 ++++ src/gsm/gsm0808_utils.c | 73 ++++++++++++++++++++++++++++++++ src/gsm/libosmogsm.map | 2 + tests/gsm0808/gsm0808_test.c | 31 ++++++++++++++ 5 files changed, 123 insertions(+) diff --git a/include/osmocom/gsm/gsm0808_utils.h b/include/osmocom/gsm/gsm0808_utils.h index b5ddbdb7..48e737d1 100644 --- a/include/osmocom/gsm/gsm0808_utils.h +++ b/include/osmocom/gsm/gsm0808_utils.h @@ -47,3 +47,11 @@ uint8_t gsm0808_enc_speech_codec_list(struct msgb *msg, /* Decode Speech Codec list */ int gsm0808_dec_speech_codec_list(struct gsm0808_speech_codec_list *scl, const uint8_t *elem, uint8_t len); + +/* Encode Channel Type element */ +uint8_t gsm0808_enc_channel_type(struct msgb *msg, + const struct gsm0808_channel_type *ct); + +/* Decode Channel Type element */ +int gsm0808_dec_channel_type(struct gsm0808_channel_type *ct, + const uint8_t *elem, uint8_t len); diff --git a/include/osmocom/gsm/protocol/gsm_08_08.h b/include/osmocom/gsm/protocol/gsm_08_08.h index 3e5514dc..e2355f68 100644 --- a/include/osmocom/gsm/protocol/gsm_08_08.h +++ b/include/osmocom/gsm/protocol/gsm_08_08.h @@ -438,3 +438,12 @@ struct gsm0808_speech_codec_list { struct gsm0808_speech_codec codec[SPEECH_CODEC_MAXLEN]; uint8_t len; }; + +/* 3GPP TS 48.008 3.2.2.11 Channel Type */ +#define CH_TYPE_PERM_SPCH_MAXLEN 9 +struct gsm0808_channel_type { + uint8_t ch_indctr; + uint8_t ch_rate_type; + uint8_t perm_spch[CH_TYPE_PERM_SPCH_MAXLEN]; + unsigned int perm_spch_len; +}; diff --git a/src/gsm/gsm0808_utils.c b/src/gsm/gsm0808_utils.c index eef6146d..ef0f9431 100644 --- a/src/gsm/gsm0808_utils.c +++ b/src/gsm/gsm0808_utils.c @@ -31,6 +31,8 @@ #define IP_V6_ADDR_LEN 16 #define IP_PORT_LEN 2 +#define CHANNEL_TYPE_ELEMENT_MAXLEN 11 +#define CHANNEL_TYPE_ELEMENT_MINLEN 3 /* Encode AoIP transport address element */ uint8_t gsm0808_enc_aoip_trasp_addr(struct msgb *msg, @@ -306,3 +308,74 @@ int gsm0808_dec_speech_codec_list(struct gsm0808_speech_codec_list *scl, return (int)(elem - old_elem); } + +/* Encode Channel Type element */ +uint8_t gsm0808_enc_channel_type(struct msgb *msg, + const struct gsm0808_channel_type *ct) +{ + unsigned int i; + uint8_t byte; + uint8_t *old_tail; + uint8_t *tlv_len; + + OSMO_ASSERT(msg); + OSMO_ASSERT(ct); + OSMO_ASSERT(ct->perm_spch_len <= CHANNEL_TYPE_ELEMENT_MAXLEN - 2); + + /* FIXME: Implement encoding support for Data + * and Speech + CTM Text Telephony */ + if ((ct->ch_indctr & 0x0f) != GSM0808_CHAN_SPEECH + && (ct->ch_indctr & 0x0f) != GSM0808_CHAN_SIGN) + OSMO_ASSERT(false); + + msgb_put_u8(msg, GSM0808_IE_CHANNEL_TYPE); + tlv_len = msgb_put(msg, 1); + old_tail = msg->tail; + + msgb_put_u8(msg, ct->ch_indctr & 0x0f); + msgb_put_u8(msg, ct->ch_rate_type); + + for (i = 0; i < ct->perm_spch_len; i++) { + byte = ct->perm_spch[i]; + + if (i < ct->perm_spch_len - 1) + byte |= 0x80; + msgb_put_u8(msg, byte); + } + + *tlv_len = (uint8_t) (msg->tail - old_tail); + return *tlv_len + 2; +} + +/* Decode Channel Type element */ +int gsm0808_dec_channel_type(struct gsm0808_channel_type *ct, + const uint8_t *elem, uint8_t len) +{ + unsigned int i; + uint8_t byte; + const uint8_t *old_elem = elem; + + OSMO_ASSERT(ct); + if (!elem) + return -EINVAL; + if (len <= 0) + return -EINVAL; + + memset(ct, 0, sizeof(*ct)); + + ct->ch_indctr = (*elem) & 0x0f; + elem++; + ct->ch_rate_type = (*elem) & 0x0f; + elem++; + + for (i = 0; i < ARRAY_SIZE(ct->perm_spch); i++) { + byte = *elem; + elem++; + ct->perm_spch[i] = byte & 0x7f; + if ((byte & 0x80) == 0x00) + break; + } + ct->perm_spch_len = i + 1; + + return (int)(elem - old_elem); +} diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map index 518a5aa8..2ba0c427 100644 --- a/src/gsm/libosmogsm.map +++ b/src/gsm/libosmogsm.map @@ -146,6 +146,8 @@ gsm0808_enc_speech_codec; gsm0808_dec_speech_codec; gsm0808_enc_speech_codec_list; gsm0808_dec_speech_codec_list; +gsm0808_enc_channel_type; +gsm0808_dec_channel_type; gsm0858_rsl_ul_meas_enc; diff --git a/tests/gsm0808/gsm0808_test.c b/tests/gsm0808/gsm0808_test.c index 4a4a1084..0dd9e846 100644 --- a/tests/gsm0808/gsm0808_test.c +++ b/tests/gsm0808/gsm0808_test.c @@ -541,6 +541,36 @@ static void test_gsm0808_enc_dec_speech_codec_list() msgb_free(msg); } +static void test_gsm0808_enc_dec_channel_type() +{ + struct gsm0808_channel_type enc_ct; + struct gsm0808_channel_type dec_ct; + struct msgb *msg; + uint8_t ct_enc_expected[] = { GSM0808_IE_CHANNEL_TYPE, + 0x04, 0x01, 0x0b, 0xa1, 0x25 + }; + uint8_t rc_enc; + int rc_dec; + + memset(&enc_ct, 0, sizeof(enc_ct)); + enc_ct.ch_indctr = GSM0808_CHAN_SPEECH; + enc_ct.ch_rate_type = GSM0808_SPEECH_HALF_PREF; + enc_ct.perm_spch[0] = GSM0808_PERM_FR3; + enc_ct.perm_spch[1] = GSM0808_PERM_HR3; + enc_ct.perm_spch_len = 2; + + msg = msgb_alloc(1024, "output buffer"); + rc_enc = gsm0808_enc_channel_type(msg, &enc_ct); + OSMO_ASSERT(rc_enc == 6); + OSMO_ASSERT(memcmp(ct_enc_expected, msg->data, msg->len) == 0); + + rc_dec = gsm0808_dec_channel_type(&dec_ct, msg->data + 2, msg->len - 2); + OSMO_ASSERT(rc_dec == 4); + OSMO_ASSERT(memcmp(&enc_ct, &dec_ct, sizeof(enc_ct)) == 0); + + msgb_free(msg); +} + int main(int argc, char **argv) { printf("Testing generation of GSM0808 messages\n"); @@ -566,6 +596,7 @@ int main(int argc, char **argv) test_gsm0808_enc_dec_speech_codec_ext(); test_gsm0808_enc_dec_speech_codec_ext_with_cfg(); test_gsm0808_enc_dec_speech_codec_list(); + test_gsm0808_enc_dec_channel_type(); printf("Done\n"); return EXIT_SUCCESS; -- cgit v1.2.3