Harald Welte | ec8b450 | 2010-02-20 20:34:29 +0100 | [diff] [blame] | 1 | #include <stdio.h> |
| 2 | #include <stdint.h> |
Pablo Neira Ayuso | 8341934 | 2011-03-22 16:36:13 +0100 | [diff] [blame] | 3 | #include <osmocom/core/utils.h> |
| 4 | #include <osmocom/gsm/tlv.h> |
Harald Welte | ec8b450 | 2010-02-20 20:34:29 +0100 | [diff] [blame] | 5 | |
Harald Welte | 57c7d37 | 2011-08-17 17:50:55 +0200 | [diff] [blame] | 6 | /*! \addtogroup tlv |
| 7 | * @{ |
| 8 | */ |
| 9 | /*! \file tlv.c */ |
| 10 | |
Harald Welte | ec8b450 | 2010-02-20 20:34:29 +0100 | [diff] [blame] | 11 | struct tlv_definition tvlv_att_def; |
| 12 | |
Harald Welte | 57c7d37 | 2011-08-17 17:50:55 +0200 | [diff] [blame] | 13 | /*! \brief Dump pasred TLV structure to stdout */ |
Harald Welte | ec8b450 | 2010-02-20 20:34:29 +0100 | [diff] [blame] | 14 | int tlv_dump(struct tlv_parsed *dec) |
| 15 | { |
| 16 | int i; |
| 17 | |
| 18 | for (i = 0; i <= 0xff; i++) { |
| 19 | if (!dec->lv[i].val) |
| 20 | continue; |
| 21 | printf("T=%02x L=%d\n", i, dec->lv[i].len); |
| 22 | } |
| 23 | return 0; |
| 24 | } |
| 25 | |
Harald Welte | 57c7d37 | 2011-08-17 17:50:55 +0200 | [diff] [blame] | 26 | /*! \brief Parse a single TLV encoded IE |
| 27 | * \param[out] o_tag the tag of the IE that was found |
| 28 | * \param[out] o_len length of the IE that was found |
| 29 | * \param[out] o_val pointer to the data of the IE that was found |
| 30 | * \param[in] def structure defining the valid TLV tags / configurations |
| 31 | * \param[in] buf the input data buffer to be parsed |
| 32 | * \param[in] buf_len length of the input data buffer |
| 33 | * \returns number of bytes consumed by the TLV entry / IE parsed |
Harald Welte | ec8b450 | 2010-02-20 20:34:29 +0100 | [diff] [blame] | 34 | */ |
| 35 | int tlv_parse_one(uint8_t *o_tag, uint16_t *o_len, const uint8_t **o_val, |
| 36 | const struct tlv_definition *def, |
| 37 | const uint8_t *buf, int buf_len) |
| 38 | { |
| 39 | uint8_t tag; |
| 40 | int len; |
| 41 | |
| 42 | tag = *buf; |
| 43 | *o_tag = tag; |
| 44 | |
Andreas Eversberg | cd2a74b | 2010-07-12 08:55:14 +0200 | [diff] [blame] | 45 | /* single octet TV IE */ |
| 46 | if (def->def[tag & 0xf0].type == TLV_TYPE_SINGLE_TV) { |
| 47 | *o_tag = tag & 0xf0; |
| 48 | *o_val = buf; |
| 49 | *o_len = 1; |
| 50 | return 1; |
| 51 | } |
| 52 | |
Harald Welte | ec8b450 | 2010-02-20 20:34:29 +0100 | [diff] [blame] | 53 | /* FIXME: use tables for knwon IEI */ |
| 54 | switch (def->def[tag].type) { |
| 55 | case TLV_TYPE_T: |
| 56 | /* GSM TS 04.07 11.2.4: Type 1 TV or Type 2 T */ |
| 57 | *o_val = buf; |
| 58 | *o_len = 0; |
| 59 | len = 1; |
| 60 | break; |
| 61 | case TLV_TYPE_TV: |
| 62 | *o_val = buf+1; |
| 63 | *o_len = 1; |
| 64 | len = 2; |
| 65 | break; |
| 66 | case TLV_TYPE_FIXED: |
| 67 | *o_val = buf+1; |
| 68 | *o_len = def->def[tag].fixed_len; |
| 69 | len = def->def[tag].fixed_len + 1; |
| 70 | break; |
| 71 | case TLV_TYPE_TLV: |
| 72 | /* GSM TS 04.07 11.2.4: Type 4 TLV */ |
| 73 | if (buf + 1 > buf + buf_len) |
| 74 | return -1; |
| 75 | *o_val = buf+2; |
| 76 | *o_len = *(buf+1); |
| 77 | len = *o_len + 2; |
| 78 | if (len > buf_len) |
| 79 | return -2; |
| 80 | break; |
| 81 | case TLV_TYPE_TvLV: |
| 82 | if (*(buf+1) & 0x80) { |
| 83 | /* like TLV, but without highest bit of len */ |
| 84 | if (buf + 1 > buf + buf_len) |
| 85 | return -1; |
| 86 | *o_val = buf+2; |
| 87 | *o_len = *(buf+1) & 0x7f; |
| 88 | len = *o_len + 2; |
| 89 | if (len > buf_len) |
| 90 | return -2; |
| 91 | break; |
| 92 | } |
| 93 | /* like TL16V, fallthrough */ |
| 94 | case TLV_TYPE_TL16V: |
| 95 | if (2 > buf_len) |
| 96 | return -1; |
| 97 | *o_val = buf+3; |
| 98 | *o_len = *(buf+1) << 8 | *(buf+2); |
| 99 | len = *o_len + 3; |
| 100 | if (len > buf_len) |
| 101 | return -2; |
| 102 | break; |
| 103 | default: |
| 104 | return -3; |
| 105 | } |
| 106 | |
| 107 | return len; |
| 108 | } |
| 109 | |
Harald Welte | 57c7d37 | 2011-08-17 17:50:55 +0200 | [diff] [blame] | 110 | /*! \brief Parse an entire buffer of TLV encoded Information Eleemnts |
| 111 | * \param[out] dec caller-allocated pointer to \ref tlv_parsed |
| 112 | * \param[in] def structure defining the valid TLV tags / configurations |
| 113 | * \param[in] buf the input data buffer to be parsed |
| 114 | * \param[in] buf_len length of the input data buffer |
| 115 | * \param[in] lv_tag an initial LV tag at the start of the buffer |
| 116 | * \param[in] lv_tag2 a second initial LV tag following the \a lv_tag |
| 117 | * \returns number of bytes consumed by the TLV entry / IE parsed |
Harald Welte | ec8b450 | 2010-02-20 20:34:29 +0100 | [diff] [blame] | 118 | */ |
| 119 | int tlv_parse(struct tlv_parsed *dec, const struct tlv_definition *def, |
| 120 | const uint8_t *buf, int buf_len, uint8_t lv_tag, |
| 121 | uint8_t lv_tag2) |
| 122 | { |
| 123 | int ofs = 0, num_parsed = 0; |
| 124 | uint16_t len; |
| 125 | |
| 126 | memset(dec, 0, sizeof(*dec)); |
| 127 | |
| 128 | if (lv_tag) { |
| 129 | if (ofs > buf_len) |
| 130 | return -1; |
| 131 | dec->lv[lv_tag].val = &buf[ofs+1]; |
| 132 | dec->lv[lv_tag].len = buf[ofs]; |
| 133 | len = dec->lv[lv_tag].len + 1; |
| 134 | if (ofs + len > buf_len) |
| 135 | return -2; |
| 136 | num_parsed++; |
| 137 | ofs += len; |
| 138 | } |
| 139 | if (lv_tag2) { |
| 140 | if (ofs > buf_len) |
| 141 | return -1; |
| 142 | dec->lv[lv_tag2].val = &buf[ofs+1]; |
| 143 | dec->lv[lv_tag2].len = buf[ofs]; |
| 144 | len = dec->lv[lv_tag2].len + 1; |
| 145 | if (ofs + len > buf_len) |
| 146 | return -2; |
| 147 | num_parsed++; |
| 148 | ofs += len; |
| 149 | } |
| 150 | |
| 151 | while (ofs < buf_len) { |
| 152 | int rv; |
| 153 | uint8_t tag; |
| 154 | const uint8_t *val; |
| 155 | |
| 156 | rv = tlv_parse_one(&tag, &len, &val, def, |
| 157 | &buf[ofs], buf_len-ofs); |
| 158 | if (rv < 0) |
| 159 | return rv; |
| 160 | dec->lv[tag].val = val; |
| 161 | dec->lv[tag].len = len; |
| 162 | ofs += rv; |
| 163 | num_parsed++; |
| 164 | } |
| 165 | //tlv_dump(dec); |
| 166 | return num_parsed; |
| 167 | } |
| 168 | |
Harald Welte | 57c7d37 | 2011-08-17 17:50:55 +0200 | [diff] [blame] | 169 | /*! \brief take a master (src) tlvdev and fill up all empty slots in 'dst' */ |
Harald Welte | ec8b450 | 2010-02-20 20:34:29 +0100 | [diff] [blame] | 170 | void tlv_def_patch(struct tlv_definition *dst, const struct tlv_definition *src) |
| 171 | { |
| 172 | int i; |
| 173 | |
| 174 | for (i = 0; i < ARRAY_SIZE(dst->def); i++) { |
| 175 | if (src->def[i].type == TLV_TYPE_NONE) |
| 176 | continue; |
| 177 | if (dst->def[i].type == TLV_TYPE_NONE) |
| 178 | dst->def[i] = src->def[i]; |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | static __attribute__((constructor)) void on_dso_load_tlv(void) |
| 183 | { |
| 184 | int i; |
| 185 | for (i = 0; i < ARRAY_SIZE(tvlv_att_def.def); i++) |
| 186 | tvlv_att_def.def[i].type = TLV_TYPE_TvLV; |
| 187 | } |
Harald Welte | 57c7d37 | 2011-08-17 17:50:55 +0200 | [diff] [blame] | 188 | |
| 189 | /*! }@ */ |