diff options
Diffstat (limited to 'epan/dissectors/file-png.c')
| -rw-r--r-- | epan/dissectors/file-png.c | 654 |
1 files changed, 654 insertions, 0 deletions
diff --git a/epan/dissectors/file-png.c b/epan/dissectors/file-png.c new file mode 100644 index 00000000..005bbb8f --- /dev/null +++ b/epan/dissectors/file-png.c @@ -0,0 +1,654 @@ +/* file-png.c + * + * Routines for PNG (Portable Network Graphics) image file dissection + * + * Copyright 2006 Ronnie Sahlberg + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 Gerald Combs + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ +/* See http://www.w3.org/TR/PNG for specification + */ +#include "config.h" + +#include <epan/packet.h> +#include <epan/expert.h> + + +#define MAKE_TYPE_VAL(a, b, c, d) ((a)<<24 | (b)<<16 | (c)<<8 | (d)) + +#define CHUNK_TYPE_IHDR MAKE_TYPE_VAL('I', 'H', 'D', 'R') +#define CHUNK_TYPE_bKGD MAKE_TYPE_VAL('b', 'K', 'G', 'D') +#define CHUNK_TYPE_gAMA MAKE_TYPE_VAL('g', 'A', 'M', 'A') +#define CHUNK_TYPE_iCCP MAKE_TYPE_VAL('i', 'C', 'C', 'P') +#define CHUNK_TYPE_cHRM MAKE_TYPE_VAL('c', 'H', 'R', 'M') +#define CHUNK_TYPE_pHYs MAKE_TYPE_VAL('p', 'H', 'Y', 's') +#define CHUNK_TYPE_iTXt MAKE_TYPE_VAL('i', 'T', 'X', 't') +#define CHUNK_TYPE_tEXt MAKE_TYPE_VAL('t', 'E', 'X', 't') +#define CHUNK_TYPE_sBIT MAKE_TYPE_VAL('s', 'B', 'I', 'T') +#define CHUNK_TYPE_sRGB MAKE_TYPE_VAL('s', 'R', 'G', 'B') +#define CHUNK_TYPE_tIME MAKE_TYPE_VAL('t', 'I', 'M', 'E') +#define CHUNK_TYPE_IDAT MAKE_TYPE_VAL('I', 'D', 'A', 'T') +#define CHUNK_TYPE_IEND MAKE_TYPE_VAL('I', 'E', 'N', 'D') +#define CHUNK_TYPE_tRNS MAKE_TYPE_VAL('t', 'R', 'N', 'S') +#define CHUNK_TYPE_PLTE MAKE_TYPE_VAL('P', 'L', 'T', 'E') + +static const value_string chunk_types[] = { + { CHUNK_TYPE_IHDR, "Image Header" }, + { CHUNK_TYPE_bKGD, "Background colour" }, + { CHUNK_TYPE_gAMA, "Image gamma" }, + { CHUNK_TYPE_iCCP, "Embedded ICC profile" }, + { CHUNK_TYPE_cHRM, "Primary chromaticities and white point" }, + { CHUNK_TYPE_pHYs, "Physical pixel dimensions" }, + { CHUNK_TYPE_iTXt, "International textual data" }, + { CHUNK_TYPE_tEXt, "Textual data" }, + { CHUNK_TYPE_sBIT, "Significant bits" }, + { CHUNK_TYPE_sRGB, "Standard RGB colour space" }, + { CHUNK_TYPE_tIME, "Image last-modification time" }, + { CHUNK_TYPE_IDAT, "Image data chunk" }, + { CHUNK_TYPE_IEND, "Image Trailer" }, + { CHUNK_TYPE_tRNS, "Transparency" }, + { CHUNK_TYPE_PLTE, "Palette" }, + { 0, NULL } +}; + + +void proto_register_png(void); +void proto_reg_handoff_png(void); + +static const true_false_string png_chunk_anc = { + "This is an ANCILLARY chunk", + "This is a CRITICAL chunk" +}; + +static const true_false_string png_chunk_priv = { + "This is a PRIVATE chunk", + "This is a PUBLIC chunk" +}; + +static const true_false_string png_chunk_stc = { + "This chunk is SAFE TO COPY", + "This chunk is NOT safe to copy" +}; + +static const value_string colour_type_vals[] = { + { 0, "Greyscale"}, + { 2, "Truecolour"}, + { 3, "Indexed-colour"}, + { 4, "Greyscale with alpha"}, + { 6, "Truecolour with alpha"}, + { 0, NULL } +}; + +static const value_string compression_method_vals[] = { + { 0, "Deflate"}, + { 0, NULL } +}; + +static const value_string filter_method_vals[] = { + { 0, "Adaptive"}, + { 0, NULL } +}; + +static const value_string interlace_method_vals[] = { + { 0, "No interlace"}, + { 1, "Adam7"}, + { 0, NULL } +}; + +static const value_string srgb_intent_vals[] = { + { 0, "Perceptual" }, + { 1, "Relative colorimetric" }, + { 2, "Saturation" }, + { 3, "Absolute colorimetric" }, + { 0, NULL } +}; + +static const value_string phys_unit_vals[] = { + { 0, "Unit is unknown"}, + { 1, "Unit is METRE"}, + { 0, NULL } +}; + +static int proto_png = -1; + +static int hf_png_bkgd_blue = -1; +static int hf_png_bkgd_green = -1; +static int hf_png_bkgd_greyscale = -1; +static int hf_png_bkgd_palette_index = -1; +static int hf_png_bkgd_red = -1; +static int hf_png_chrm_blue_x = -1; +static int hf_png_chrm_blue_y = -1; +static int hf_png_chrm_green_x = -1; +static int hf_png_chrm_green_y = -1; +static int hf_png_chrm_red_x = -1; +static int hf_png_chrm_red_y = -1; +static int hf_png_chrm_white_x = -1; +static int hf_png_chrm_white_y = -1; +static int hf_png_chunk_crc = -1; +static int hf_png_chunk_data = -1; +static int hf_png_chunk_flag_anc = -1; +static int hf_png_chunk_flag_priv = -1; +static int hf_png_chunk_flag_stc = -1; +static int hf_png_chunk_len = -1; +static int hf_png_chunk_type_str = -1; +static int hf_png_gama_gamma = -1; +static int hf_png_ihdr_bitdepth = -1; +static int hf_png_ihdr_colour_type = -1; +static int hf_png_ihdr_compression_method = -1; +static int hf_png_ihdr_filter_method = -1; +static int hf_png_ihdr_height = -1; +static int hf_png_ihdr_interlace_method = -1; +static int hf_png_ihdr_width = -1; +static int hf_png_phys_horiz = -1; +static int hf_png_phys_unit = -1; +static int hf_png_phys_vert = -1; +static int hf_png_signature = -1; +static int hf_png_srgb_intent = -1; +static int hf_png_text_keyword = -1; +static int hf_png_text_string = -1; +static int hf_png_time_day = -1; +static int hf_png_time_hour = -1; +static int hf_png_time_minute = -1; +static int hf_png_time_month = -1; +static int hf_png_time_second = -1; +static int hf_png_time_year = -1; + +static gint ett_png = -1; +static gint ett_png_chunk = -1; + +static expert_field ei_png_chunk_too_large = EI_INIT; + +static dissector_handle_t png_handle; + +static void +dissect_png_ihdr(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree) +{ + proto_tree_add_item(tree, hf_png_ihdr_width, tvb, 0, 4, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_ihdr_height, tvb, 4, 4, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_ihdr_bitdepth, tvb, 8, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_ihdr_colour_type, tvb, 9, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_ihdr_compression_method, tvb, 10, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_ihdr_filter_method, tvb, 11, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_ihdr_interlace_method, tvb, 12, 1, ENC_BIG_ENDIAN); + +} + +static void +dissect_png_srgb(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree) +{ + proto_tree_add_item(tree, hf_png_srgb_intent, + tvb, 0, 1, ENC_BIG_ENDIAN); +} + +static void +dissect_png_text(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree) +{ + gint offset=0, nul_offset; + + nul_offset = tvb_find_guint8(tvb, offset, tvb_captured_length_remaining(tvb, offset), 0); + /* nul_offset == 0 means empty keyword, this is not allowed by the png standard */ + if (nul_offset<=0) { + /* XXX exception */ + return; + } + + proto_tree_add_item(tree, hf_png_text_keyword, tvb, offset, nul_offset, ENC_ISO_8859_1|ENC_NA); + offset = nul_offset+1; /* length of the key word + 0 character */ + + proto_tree_add_item(tree, hf_png_text_string, tvb, offset, tvb_captured_length_remaining(tvb, offset), ENC_ISO_8859_1|ENC_NA); + +} + +static void +dissect_png_time(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree) +{ + proto_tree_add_item(tree, hf_png_time_year, tvb, 0, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_time_month, tvb, 2, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_time_day, tvb, 3, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_time_hour, tvb, 4, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_time_minute, tvb, 5, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_time_second, tvb, 6, 1, ENC_BIG_ENDIAN); +} + +static void +dissect_png_phys(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree) +{ + proto_tree_add_item(tree, hf_png_phys_horiz, tvb, 0, 4, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_phys_vert, tvb, 4, 4, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_phys_unit, tvb, 8, 1, ENC_BIG_ENDIAN); +} + +static void +dissect_png_bkgd(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree) +{ + switch(tvb_reported_length(tvb)){ + case 1: /* colour type 3 */ + proto_tree_add_item(tree, hf_png_bkgd_palette_index, tvb, 0, 1, ENC_BIG_ENDIAN); + break; + case 2: /* colour type 0, 4 */ + proto_tree_add_item(tree, hf_png_bkgd_greyscale, tvb, 0, 2, ENC_BIG_ENDIAN); + break; + case 6: /* colour type 2, 6 */ + proto_tree_add_item(tree, hf_png_bkgd_red, tvb, 0, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_bkgd_green, tvb, 2, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(tree, hf_png_bkgd_blue, tvb, 4, 2, ENC_BIG_ENDIAN); + break; + } +} + +static void +dissect_png_chrm(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree) +{ + float wx, wy, rx, ry, gx, gy, bx, by; + gint offset = 0; + + wx = tvb_get_ntohl(tvb, offset) / 100000.0f; + proto_tree_add_float(tree, hf_png_chrm_white_x, + tvb, offset, 4, wx); + offset += 4; + + wy = tvb_get_ntohl(tvb, offset) / 100000.0f; + proto_tree_add_float(tree, hf_png_chrm_white_y, + tvb, offset, 4, wy); + offset += 4; + + rx = tvb_get_ntohl(tvb, offset) / 100000.0f; + proto_tree_add_float(tree, hf_png_chrm_red_x, + tvb, offset, 4, rx); + offset += 4; + + ry = tvb_get_ntohl(tvb, offset) / 100000.0f; + proto_tree_add_float(tree, hf_png_chrm_red_y, + tvb, offset, 4, ry); + offset += 4; + + gx = tvb_get_ntohl(tvb, offset) / 100000.0f; + proto_tree_add_float(tree, hf_png_chrm_green_x, + tvb, offset, 4, gx); + offset += 4; + + gy = tvb_get_ntohl(tvb, offset) / 100000.0f; + proto_tree_add_float(tree, hf_png_chrm_green_y, + tvb, offset, 4, gy); + offset += 4; + + bx = tvb_get_ntohl(tvb, offset) / 100000.0f; + proto_tree_add_float(tree, hf_png_chrm_blue_x, + tvb, offset, 4, bx); + offset += 4; + + by = tvb_get_ntohl(tvb, offset) / 100000.0f; + proto_tree_add_float(tree, hf_png_chrm_blue_y, + tvb, offset, 4, by); +} + +static void +dissect_png_gama(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree) +{ + float gamma; + + gamma = tvb_get_ntohl(tvb, 0) / 100000.0f; + proto_tree_add_float(tree, hf_png_gama_gamma, + tvb, 0, 4, gamma); +} + +static gint +dissect_png(tvbuff_t *tvb, packet_info *pinfo, proto_tree *parent_tree, void *data _U_) +{ + proto_tree *tree; + proto_item *ti; + gint offset=0; + /* http://libpng.org/pub/png/spec/1.2/PNG-Structure.html#PNG-file-signature */ + static const guint8 magic[8] = { 137, 80, 78, 71, 13, 10, 26, 10 }; + + if (tvb_captured_length(tvb) < 20) + return 0; + if (tvb_memeql(tvb, 0, magic, sizeof(magic)) != 0) + return 0; + + col_append_str(pinfo->cinfo, COL_INFO, " (PNG)"); + + ti=proto_tree_add_item(parent_tree, proto_png, tvb, offset, -1, ENC_NA); + tree=proto_item_add_subtree(ti, ett_png); + + proto_tree_add_item(tree, hf_png_signature, tvb, offset, 8, ENC_NA); + offset+=8; + + while(tvb_reported_length_remaining(tvb, offset) > 0){ + guint32 len_field; + proto_item *len_it; + proto_tree *chunk_tree; + guint32 type; + guint8 *type_str; + tvbuff_t *chunk_tvb; + + len_field = tvb_get_ntohl(tvb, offset); + + type = tvb_get_ntohl(tvb, offset+4); + type_str = tvb_get_string_enc(pinfo->pool, + tvb, offset+4, 4, ENC_ASCII|ENC_NA); + + /* 4 byte len field, 4 byte chunk type, 4 byte CRC */ + chunk_tree = proto_tree_add_subtree_format(tree, tvb, offset, 4+4+len_field+4, ett_png_chunk, NULL, + "%s (%s)", val_to_str_const(type, chunk_types, "unknown"), type_str); + + len_it = proto_tree_add_item(chunk_tree, hf_png_chunk_len, + tvb, offset, 4, ENC_BIG_ENDIAN); + offset+=4; + if (len_field > G_MAXINT) { + expert_add_info(pinfo, len_it, &ei_png_chunk_too_large); + return offset; + } + + proto_tree_add_item(chunk_tree, hf_png_chunk_type_str, + tvb, offset, 4, ENC_ASCII); + + proto_tree_add_item(chunk_tree, hf_png_chunk_flag_anc, tvb, offset, 4, ENC_BIG_ENDIAN); + proto_tree_add_item(chunk_tree, hf_png_chunk_flag_priv, tvb, offset, 4, ENC_BIG_ENDIAN); + proto_tree_add_item(chunk_tree, hf_png_chunk_flag_stc, tvb, offset, 4, ENC_BIG_ENDIAN); + offset+=4; + + chunk_tvb=tvb_new_subset_length(tvb, offset, len_field); + switch (type) { + case CHUNK_TYPE_IHDR: + dissect_png_ihdr(chunk_tvb, pinfo, chunk_tree); + break; + case CHUNK_TYPE_bKGD: + dissect_png_bkgd(chunk_tvb, pinfo, chunk_tree); + break; + case CHUNK_TYPE_cHRM: + dissect_png_chrm(chunk_tvb, pinfo, chunk_tree); + break; + case CHUNK_TYPE_gAMA: + dissect_png_gama(chunk_tvb, pinfo, chunk_tree); + break; + case CHUNK_TYPE_pHYs: + dissect_png_phys(chunk_tvb, pinfo, chunk_tree); + break; + case CHUNK_TYPE_sRGB: + dissect_png_srgb(chunk_tvb, pinfo, chunk_tree); + break; + case CHUNK_TYPE_tEXt: + dissect_png_text(chunk_tvb, pinfo, chunk_tree); + break; + case CHUNK_TYPE_tIME: + dissect_png_time(chunk_tvb, pinfo, chunk_tree); + break; + default: + if (len_field>0) { + proto_tree_add_item(chunk_tree, hf_png_chunk_data, + tvb, offset, len_field, ENC_NA); + } + break; + } + offset += len_field; + + proto_tree_add_item(chunk_tree, hf_png_chunk_crc, tvb, offset, 4, ENC_BIG_ENDIAN); + offset+=4; + } + return offset; +} + +void +proto_register_png(void) +{ + static hf_register_info hf[] = { + { &hf_png_signature, + { "PNG Signature", "png.signature", + FT_BYTES, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chunk_data, + { "Data", "png.chunk.data", + FT_NONE, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chunk_type_str, + { "Chunk", "png.chunk.type", + FT_STRING, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chunk_len, + { "Len", "png.chunk.len", + FT_UINT32, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chunk_crc, + { "CRC", "png.chunk.crc", + FT_UINT32, BASE_HEX, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chunk_flag_anc, + { "Ancillary", "png.chunk.flag.ancillary", + FT_BOOLEAN, 32, TFS(&png_chunk_anc), 0x20000000, + NULL, HFILL } + }, + { &hf_png_chunk_flag_priv, + { "Private", "png.chunk.flag.private", + FT_BOOLEAN, 32, TFS(&png_chunk_priv), 0x00200000, + NULL, HFILL } + }, + { &hf_png_chunk_flag_stc, + { "Safe To Copy", "png.chunk.flag.stc", + FT_BOOLEAN, 32, TFS(&png_chunk_stc), 0x00000020, + NULL, HFILL } + }, + { &hf_png_ihdr_width, + { "Width", "png.ihdr.width", + FT_UINT32, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_ihdr_height, + { "Height", "png.ihdr.height", + FT_UINT32, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_ihdr_bitdepth, + { "Bit Depth", "png.ihdr.bitdepth", + FT_UINT8, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_ihdr_colour_type, + { "Colour Type", "png.ihdr.colour_type", + FT_UINT8, BASE_DEC, VALS(colour_type_vals), 0, + NULL, HFILL } + }, + { &hf_png_ihdr_compression_method, + { "Compression Method", "png.ihdr.compression_method", + FT_UINT8, BASE_DEC, VALS(compression_method_vals), 0, + NULL, HFILL } + }, + { &hf_png_ihdr_filter_method, + { "Filter Method", "png.ihdr.filter_method", + FT_UINT8, BASE_DEC, VALS(filter_method_vals), 0, + NULL, HFILL } + }, + { &hf_png_ihdr_interlace_method, + { "Interlace Method", "png.ihdr.interlace_method", + FT_UINT8, BASE_DEC, VALS(interlace_method_vals), 0, + NULL, HFILL } + }, + { &hf_png_srgb_intent, + { "Intent", "png.srgb.intent", + FT_UINT8, BASE_DEC, VALS(srgb_intent_vals), 0, + NULL, HFILL } + }, + { &hf_png_text_keyword, + { "Keyword", "png.text.keyword", + FT_STRING, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_text_string, + { "String", "png.text.string", + FT_STRING, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_time_year, + { "Year", "png.time.year", + FT_UINT16, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_time_month, + { "Month", "png.time.month", + FT_UINT8, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_time_day, + { "Day", "png.time.day", + FT_UINT8, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_time_hour, + { "Hour", "png.time.hour", + FT_UINT8, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_time_minute, + { "Minute", "png.time.minute", + FT_UINT8, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_time_second, + { "Second", "png.time.second", + FT_UINT8, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_phys_horiz, + { "Horizontal pixels per unit", "png.phys.horiz", + FT_UINT32, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_phys_vert, + { "Vertical pixels per unit", "png.phys.vert", + FT_UINT32, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_phys_unit, + { "Unit", "png.phys.unit", + FT_UINT8, BASE_DEC, VALS(phys_unit_vals), 0, + NULL, HFILL } + }, + { &hf_png_bkgd_palette_index, + { "Palette Index", "png.bkgd.palette_index", + FT_UINT8, BASE_DEC, NULL, 0, + NULL, HFILL } + }, + { &hf_png_bkgd_greyscale, + { "Greyscale", "png.bkgd.greyscale", + FT_UINT16, BASE_HEX, NULL, 0, + NULL, HFILL } + }, + { &hf_png_bkgd_red, + { "Red", "png.bkgd.red", + FT_UINT16, BASE_HEX, NULL, 0, + NULL, HFILL } + }, + { &hf_png_bkgd_green, + { "Green", "png.bkgd.green", + FT_UINT16, BASE_HEX, NULL, 0, + NULL, HFILL } + }, + { &hf_png_bkgd_blue, + { "Blue", "png.bkgd.blue", + FT_UINT16, BASE_HEX, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chrm_white_x, + { "White X", "png.chrm.white.x", + FT_FLOAT, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chrm_white_y, + { "White Y", "png.chrm.white.y", + FT_FLOAT, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chrm_red_x, + { "Red X", "png.chrm.red.x", + FT_FLOAT, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chrm_red_y, + { "Red Y", "png.chrm.red.y", + FT_FLOAT, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chrm_green_x, + { "Green X", "png.chrm.green.x", + FT_FLOAT, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chrm_green_y, + { "Green Y", "png.chrm.green.y", + FT_FLOAT, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chrm_blue_x, + { "Blue X", "png.chrm.blue.x", + FT_FLOAT, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_chrm_blue_y, + { "Blue Y", "png.chrm.blue.y", + FT_FLOAT, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + { &hf_png_gama_gamma, + { "Gamma", "png.gama.gamma", + FT_FLOAT, BASE_NONE, NULL, 0, + NULL, HFILL } + }, + }; + + static gint *ett[] = + { + &ett_png, + &ett_png_chunk, + }; + + static ei_register_info ei[] = { + { &ei_png_chunk_too_large, + { "png.chunk_too_large", PI_PROTOCOL, PI_WARN, + "chunk size too large, dissection of this chunk is not supported", EXPFILL }} + }; + expert_module_t *expert_png; + + proto_png = proto_register_protocol("Portable Network Graphics","PNG","png"); + proto_register_field_array(proto_png, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + + expert_png = expert_register_protocol(proto_png); + expert_register_field_array(expert_png, ei, array_length(ei)); + + png_handle = register_dissector("png", dissect_png, proto_png); +} + +static gboolean dissect_png_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) +{ + return dissect_png(tvb, pinfo, tree, NULL) > 0; +} + +void +proto_reg_handoff_png(void) +{ + dissector_add_string("media_type", "image/png", png_handle); + heur_dissector_add("http", dissect_png_heur, "PNG file in HTTP", "png_http", proto_png, HEURISTIC_ENABLE); + heur_dissector_add("wtap_file", dissect_png_heur, "PNG file in HTTP", "png_wtap", proto_png, HEURISTIC_ENABLE); +} + +/* + * Editor modelines - https://www.wireshark.org/tools/modelines.html + * + * Local variables: + * c-basic-offset: 4 + * tab-width: 8 + * indent-tabs-mode: nil + * End: + * + * vi: set shiftwidth=4 tabstop=8 expandtab: + * :indentSize=4:tabSize=8:noTabs=true: + */ |