diff options
author | Harald Welte <laforge@gnumonks.org> | 2009-05-23 06:39:58 +0000 |
---|---|---|
committer | Harald Welte <laforge@gnumonks.org> | 2009-05-23 06:39:58 +0000 |
commit | a4d49e96ab45b12fe581d6ab3cecd0727bccb317 (patch) | |
tree | dbeebd5e255e0ef1b07c1be083f8691027e46afa /src | |
parent | e7b452a7a07b75f880fadeeb650efe2bac931c7b (diff) |
Some messages have one or two length-value information elements. The is
no IE type included in the message. These information elements are
mandatory, so their actual IE type is known. The improved parse_tlv()
function allows to parse zero, one, or two length-value elements.
(Andreas Eversberg)
Diffstat (limited to 'src')
-rw-r--r-- | src/abis_nm.c | 2 | ||||
-rw-r--r-- | src/abis_rsl.c | 3 | ||||
-rw-r--r-- | src/gsm_04_08.c | 2 | ||||
-rw-r--r-- | src/tlv_parser.c | 37 |
4 files changed, 38 insertions, 6 deletions
diff --git a/src/abis_nm.c b/src/abis_nm.c index 6909f7828..0107c294e 100644 --- a/src/abis_nm.c +++ b/src/abis_nm.c @@ -365,7 +365,7 @@ static const struct tlv_definition nm_att_tlvdef = { int abis_nm_tlv_parse(struct tlv_parsed *tp, const u_int8_t *buf, int len) { - return tlv_parse(tp, &nm_att_tlvdef, buf, len); + return tlv_parse(tp, &nm_att_tlvdef, buf, len, 0, 0); } static int is_in_arr(enum abis_nm_msgtype mt, const enum abis_nm_msgtype *arr, int size) diff --git a/src/abis_rsl.c b/src/abis_rsl.c index e7f953e0c..753a66609 100644 --- a/src/abis_rsl.c +++ b/src/abis_rsl.c @@ -112,7 +112,8 @@ static const struct tlv_definition rsl_att_tlvdef = { [0xfc] = { TLV_TYPE_TV }, }, }; -#define rsl_tlv_parse(dec, buf, len) tlv_parse(dec, &rsl_att_tlvdef, buf, len) +#define rsl_tlv_parse(dec, buf, len) \ + tlv_parse(dec, &rsl_att_tlvdef, buf, len, 0, 0) static u_int8_t mdisc_by_msgtype(u_int8_t msg_type) { diff --git a/src/gsm_04_08.c b/src/gsm_04_08.c index ad7bba687..849ef4888 100644 --- a/src/gsm_04_08.c +++ b/src/gsm_04_08.c @@ -1119,7 +1119,7 @@ static int gsm48_cc_rx_setup(struct msgb *msg) call->local_lchan = msg->lchan; call->transaction_id = gh->proto_discr & 0xf0; - tlv_parse(&tp, &rsl_att_tlvdef, gh->data, payload_len); + tlv_parse(&tp, &rsl_att_tlvdef, gh->data, payload_len, 0, 0); if (!TLVP_PRESENT(&tp, GSM48_IE_CALLED_BCD)) goto err; diff --git a/src/tlv_parser.c b/src/tlv_parser.c index fe6d28926..e835f951f 100644 --- a/src/tlv_parser.c +++ b/src/tlv_parser.c @@ -13,16 +13,47 @@ int tlv_dump(struct tlv_parsed *dec) return 0; } +/* dec: output: a caller-allocated pointer to a struct tlv_parsed, + * def: input: a structure defining the valid TLV tags / configurations + * buf: input: the input data buffer to be parsed + * buf_len: input: the length of the input data buffer + * lv_tag: input: an initial LV tag at the start of the buffer + * lv_tag2: input: a second initial LV tag following lv_tag + */ int tlv_parse(struct tlv_parsed *dec, const struct tlv_definition *def, - const u_int8_t *buf, int buf_len) + const u_int8_t *buf, int buf_len, u_int8_t lv_tag, + u_int8_t lv_tag2) { u_int8_t tag, len = 1; - const u_int8_t *pos; + const u_int8_t *pos = buf; int num_parsed = 0; memset(dec, 0, sizeof(*dec)); - for (pos = buf; pos < buf+buf_len; pos += len) { + if (lv_tag) { + if (pos > buf + buf_len) + return -1; + dec->lv[lv_tag].val = pos+1; + dec->lv[lv_tag].len = *pos; + len = dec->lv[lv_tag].len + 1; + if (pos + len > buf + buf_len) + return -2; + num_parsed++; + pos += len; + } + if (lv_tag2) { + if (pos > buf + buf_len) + return -1; + dec->lv[lv_tag2].val = pos+1; + dec->lv[lv_tag2].len = *pos; + len = dec->lv[lv_tag2].len + 1; + if (pos + len > buf + buf_len) + return -2; + num_parsed++; + pos += len; + } + + for (; pos < buf+buf_len; pos += len) { tag = *pos; /* FIXME: use tables for knwon IEI */ switch (def->def[tag].type) { |