| Neels Hofmeyr | 306dc09 | 2018-09-30 05:01:20 +0200 | [diff] [blame^] | 1 | /* A Media Gateway Control Protocol Media Gateway: RFC 3435 */ |
| 2 | /* IuUP protocol handling, minimal implementation */ |
| 3 | |
| 4 | #pragma once |
| 5 | |
| 6 | #include <osmocom/core/endian.h> |
| 7 | #include <osmocom/core/msgb.h> |
| 8 | |
| 9 | #define OSMO_IUUP_HEADROOM 32 |
| 10 | |
| 11 | enum osmo_iuup_pdu_type { |
| 12 | OSMO_IUUP_PDU_DATA_WITH_CRC = 0, |
| 13 | OSMO_IUUP_PDU_CONTROL_PROCEDURE = 14, |
| 14 | }; |
| 15 | |
| 16 | enum osmo_iuup_acknack { |
| 17 | OSMO_IUUP_ACKNACK_PROCEDURE = 0, |
| 18 | OSMO_IUUP_ACKNACK_ACK = 1, |
| 19 | OSMO_IUUP_ACKNACK_NACK = 2, |
| 20 | }; |
| 21 | |
| 22 | enum osmo_iuup_procedure { |
| 23 | OSMO_IUUP_PROC_INITIALIZATION = 0, |
| 24 | OSMO_IUUP_PROC_RATE_CONTROL = 1, |
| 25 | OSMO_IUUP_PROC_TIME_ALIGNMENT = 2, |
| 26 | OSMO_IUUP_PROC_ERROR_EVENT = 3, |
| 27 | }; |
| 28 | |
| 29 | enum osmo_iuup_frame_good { |
| 30 | OSMO_IUUP_FRAME_GOOD = 0, |
| 31 | OSMO_IUUP_FRAME_BAD = 1, |
| 32 | OSMO_IUUP_FRAME_BAD_DUE_TO_RADIO = 2, |
| 33 | }; |
| 34 | |
| 35 | struct osmo_iuup_hdr_ctrl { |
| 36 | #if OSMO_IS_BIG_ENDIAN |
| 37 | uint8_t pdu_type:4, |
| 38 | ack_nack:2, |
| 39 | frame_nr:2; |
| 40 | uint8_t mode_version:4, |
| 41 | procedure:4; |
| 42 | uint8_t header_crc:6, |
| 43 | payload_crc_hi:2; |
| 44 | uint8_t payload_crc_lo; |
| 45 | uint8_t payload[0]; |
| 46 | #elif OSMO_IS_LITTLE_ENDIAN |
| 47 | uint8_t frame_nr:2, |
| 48 | ack_nack:2, |
| 49 | pdu_type:4; |
| 50 | uint8_t procedure:4, |
| 51 | mode_version:4; |
| 52 | uint8_t payload_crc_hi:2, |
| 53 | header_crc:6; |
| 54 | uint8_t payload_crc_lo; |
| 55 | uint8_t payload[0]; |
| 56 | #endif |
| 57 | } __attribute__((packed)); |
| 58 | |
| 59 | union osmo_iuup_hdr_ctrl_payload { |
| 60 | struct { |
| 61 | #if OSMO_IS_BIG_ENDIAN |
| 62 | uint8_t spare:3, |
| 63 | iptis_present:1, |
| 64 | subflows:3, |
| 65 | chain:1; |
| 66 | #elif OSMO_IS_LITTLE_ENDIAN |
| 67 | uint8_t spare:3, |
| 68 | iptis_present:1, |
| 69 | subflows:3, |
| 70 | chain:1; |
| 71 | #endif |
| 72 | } initialization; |
| 73 | |
| 74 | struct { |
| 75 | #if OSMO_IS_BIG_ENDIAN |
| 76 | uint8_t error_distance:2, |
| 77 | error_cause:6; |
| 78 | #elif OSMO_IS_LITTLE_ENDIAN |
| 79 | uint8_t error_cause:6, |
| 80 | error_distance:2; |
| 81 | #endif |
| 82 | } error_event; |
| 83 | }; |
| 84 | |
| 85 | extern const struct value_string osmo_iuup_error_cause_names[]; |
| 86 | static inline const char *osmo_iuup_error_cause_name(uint8_t val) |
| 87 | { return get_value_string(osmo_iuup_error_cause_names, val); } |
| 88 | |
| 89 | struct osmo_iuup_hdr_data { |
| 90 | #if OSMO_IS_BIG_ENDIAN |
| 91 | uint8_t pdu_type:4, |
| 92 | frame_nr:4; |
| 93 | uint8_t frame_good:2, |
| 94 | rfci:6; |
| 95 | uint8_t header_crc:6, |
| 96 | payload_crc_hi:2; |
| 97 | uint8_t payload_crc_lo; |
| 98 | #elif OSMO_IS_LITTLE_ENDIAN |
| 99 | uint8_t frame_nr:4, |
| 100 | pdu_type:4; |
| 101 | uint8_t rfci:6, |
| 102 | frame_good:2; |
| 103 | uint8_t payload_crc_hi:2, |
| 104 | header_crc:6; |
| 105 | uint8_t payload_crc_lo; |
| 106 | #endif |
| 107 | uint8_t payload[0]; |
| 108 | } __attribute__((packed)); |
| 109 | |
| 110 | int osmo_iuup_classify(bool log_errors, |
| 111 | const char *log_label, |
| 112 | struct msgb *pdu, |
| 113 | struct osmo_iuup_hdr_ctrl **is_ctrl, |
| 114 | struct osmo_iuup_hdr_data **is_data); |
| 115 | bool osmo_iuup_is_init(struct msgb *pdu); |
| 116 | void osmo_iuup_make_init_ack(struct msgb *ack); |
| 117 | void osmo_iuup_set_checksums(uint8_t *iuup_header_and_payload, unsigned int header_and_payload_len); |