4 /* gsmtap header, pseudo-header in front of the actua GSM payload */
6 /* GSMTAP is a generic header format for GSM protocol captures,
7 * it uses the IANA-assigned UDP port number 4729 and carries
8 * payload in various formats of GSM interfaces such as Um MAC
11 * Example programs generating GSMTAP data are airprobe
12 * (http://airprobe.org/) or OsmocomBB (http://bb.osmocom.org/)
17 #define GSMTAP_VERSION 0x02
19 #define GSMTAP_TYPE_UM 0x01
20 #define GSMTAP_TYPE_ABIS 0x02
21 #define GSMTAP_TYPE_UM_BURST 0x03 /* raw burst bits */
22 #define GSMTAP_TYPE_SIM 0x04
23 #define GSMTAP_TYPE_TETRA_I1 0x05 /* tetra air interface */
24 #define GSMTAP_TYPE_TETRA_I1_BURST 0x06 /* tetra air interface */
26 /* sub-types for TYPE_UM_BURST */
27 #define GSMTAP_BURST_UNKNOWN 0x00
28 #define GSMTAP_BURST_FCCH 0x01
29 #define GSMTAP_BURST_PARTIAL_SCH 0x02
30 #define GSMTAP_BURST_SCH 0x03
31 #define GSMTAP_BURST_CTS_SCH 0x04
32 #define GSMTAP_BURST_COMPACT_SCH 0x05
33 #define GSMTAP_BURST_NORMAL 0x06
34 #define GSMTAP_BURST_DUMMY 0x07
35 #define GSMTAP_BURST_ACCESS 0x08
36 #define GSMTAP_BURST_NONE 0x09
38 /* sub-types for TYPE_UM */
39 #define GSMTAP_CHANNEL_UNKNOWN 0x00
40 #define GSMTAP_CHANNEL_BCCH 0x01
41 #define GSMTAP_CHANNEL_CCCH 0x02
42 #define GSMTAP_CHANNEL_RACH 0x03
43 #define GSMTAP_CHANNEL_AGCH 0x04
44 #define GSMTAP_CHANNEL_PCH 0x05
45 #define GSMTAP_CHANNEL_SDCCH 0x06
46 #define GSMTAP_CHANNEL_SDCCH4 0x07
47 #define GSMTAP_CHANNEL_SDCCH8 0x08
48 #define GSMTAP_CHANNEL_TCH_F 0x09
49 #define GSMTAP_CHANNEL_TCH_H 0x0a
50 #define GSMTAP_CHANNEL_ACCH 0x80
52 /* sub-types for TYPE_TETRA_AIR */
53 #define GSMTAP_TETRA_BSCH 0x01
54 #define GSMTAP_TETRA_AACH 0x02
55 #define GSMTAP_TETRA_SCH_HU 0x03
56 #define GSMTAP_TETRA_SCH_HD 0x04
57 #define GSMTAP_TETRA_SCH_F 0x05
58 #define GSMTAP_TETRA_BNCH 0x06
59 #define GSMTAP_TETRA_STCH 0x07
60 #define GSMTAP_TETRA_TCH_F 0x08
62 /* flags for the ARFCN */
63 #define GSMTAP_ARFCN_F_PCS 0x8000
64 #define GSMTAP_ARFCN_F_UPLINK 0x4000
65 #define GSMTAP_ARFCN_MASK 0x3fff
67 /* IANA-assigned well-known UDP port for GSMTAP messages */
68 #define GSMTAP_UDP_PORT 4729
71 uint8_t version; /* version, set to 0x01 currently */
72 uint8_t hdr_len; /* length in number of 32bit words */
73 uint8_t type; /* see GSMTAP_TYPE_* */
74 uint8_t timeslot; /* timeslot (0..7 on Um) */
76 uint16_t arfcn; /* ARFCN (frequency) */
77 int8_t signal_dbm; /* signal level in dBm */
78 int8_t snr_db; /* signal/noise ratio in dB */
80 uint32_t frame_number; /* GSM Frame Number (FN) */
82 uint8_t sub_type; /* Type of burst/channel, see above */
83 uint8_t antenna_nr; /* Antenna Number */
84 uint8_t sub_slot; /* sub-slot within timeslot */
85 uint8_t res; /* reserved for future use (RFU) */
87 } __attribute__((packed));
89 #endif /* _GSMTAP_H */