diff options
| author | Dario Lombardo <lomato@gmail.com> | 2015-01-02 21:33:49 +0100 |
|---|---|---|
| committer | Michael Mann <mmann78@netscape.net> | 2015-01-19 03:12:01 +0000 |
| commit | f53be88408a9004e0543d2a04c7bf5d7537c4796 (patch) | |
| tree | 35c9b28fc5fc63acc7655472db14507a69b96503 /epan/dissectors/packet-json.c | |
| parent | 119416ef2765f290b4cdaaf930438f9b603abd9c (diff) | |
JSON dissector changed into heuristic dissector.
To check if a payload is json, the library libjsmn has been added to the source tree, with its licence (MIT).
TODO: the libjsmn can be used to extract tokens in the standard dissection other than heurisitic part.
HPFEEDS dissector has also been changed in order to leverage the new json dissector.
Bug: 10834
Change-Id: Ib1df2a699982dbdd2b5418e97edbdb5cbd9c8978
Reviewed-on: https://code.wireshark.org/review/6350
Petri-Dish: Alexis La Goutte <alexis.lagoutte@gmail.com>
Reviewed-by: Alexis La Goutte <alexis.lagoutte@gmail.com>
Reviewed-by: Michael Mann <mmann78@netscape.net>
Diffstat (limited to 'epan/dissectors/packet-json.c')
| -rw-r--r-- | epan/dissectors/packet-json.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/epan/dissectors/packet-json.c b/epan/dissectors/packet-json.c index 914a90f8b6..9a2c5899d1 100644 --- a/epan/dissectors/packet-json.c +++ b/epan/dissectors/packet-json.c @@ -31,6 +31,7 @@ #include <epan/packet.h> #include <epan/tvbparse.h> +#include <epan/jsmn/jsmn.h> #include <wsutil/str_util.h> #include <wsutil/unicode-utils.h> @@ -40,6 +41,8 @@ void proto_reg_handoff_json(void); static dissector_handle_t json_handle; +static int proto_json = -1; + static gint ett_json = -1; static gint ett_json_array = -1; static gint ett_json_object = -1; @@ -154,7 +157,7 @@ dissect_json(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data) proto_item_set_len(ti, offset); /* if we have some unparsed data, pass to data-text-lines dissector (?) */ - if (tvb_length_remaining(tvb, offset) > 0) { + if (tvb_reported_length_remaining(tvb, offset) > 0) { tvbuff_t *next_tvb; next_tvb = tvb_new_subset_remaining(tvb, offset); @@ -164,7 +167,7 @@ dissect_json(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data) col_append_sep_fstr(pinfo->cinfo, COL_INFO, " ", "(%s)", data_name); } - return tvb_length(tvb); + return tvb_captured_length(tvb); } static void before_object(void *tvbparse_data, const void *wanted_data _U_, tvbparse_elem_t *tok) { @@ -564,6 +567,25 @@ static void init_json_parser(void) { /* XXX, heur? */ } +/* This function leverages the libjsmn to undestand if the payload is json or not +*/ +static gboolean +dissect_json_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data) +{ + guint len = tvb_captured_length(tvb); + guint8* buf = tvb_get_string_enc(wmem_packet_scope(), tvb, 0, len, ENC_ASCII); + + jsmn_parser p; + /* We expect no more than 1024 tokens */ + jsmntok_t* t = (jsmntok_t*)wmem_alloc_array(wmem_packet_scope(), jsmntok_t, 1024); + + jsmn_init(&p); + if (jsmn_parse(&p, buf, len, t, sizeof(t)/sizeof(t[0])) < 0) { + return FALSE; + } + return (dissect_json(tvb, pinfo, tree, data) != 0); +} + void proto_register_json(void) { @@ -588,8 +610,6 @@ proto_register_json(void) }; #endif - int proto_json; - proto_json = proto_register_protocol("JavaScript Object Notation", "JSON", "json"); hfi_json = proto_registrar_get_nth(proto_json); @@ -604,6 +624,8 @@ proto_register_json(void) void proto_reg_handoff_json(void) { + heur_dissector_add("hpfeeds", dissect_json_heur, proto_json); + dissector_add_string("media_type", "application/json", json_handle); /* RFC 4627 */ dissector_add_string("media_type", "application/json-rpc", json_handle); /* JSON-RPC over HTTP */ dissector_add_string("media_type", "application/jsonrequest", json_handle); /* JSON-RPC over HTTP */ |