Wireshark dissector for Pro DJ Link protocol
fix utf-16 padded str parsing
+19
-8
+19
-8
pro_dj_link.lua
+19
-8
pro_dj_link.lua
···
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-- Simple UTF-16BE to UTF-8 conversion (ASCII only)
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function utf16_to_utf8(buf)
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local out = ""
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-
for i = 0, buf:len()-1, 2 do
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local c = buf(i+1, 1):uint()
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if c == 0 then break end
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if c < 128 then
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out = out .. string.char(c)
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local len = buf:len()
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for i = 0, len - 2, 2 do
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-- Pioneer DB strings are UTF-16BE. High byte first.
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local hi = buf(i, 1):uint()
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local lo = buf(i+1, 1):uint()
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-- Stop at first null character pair
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if hi == 0 and lo == 0 then break end
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-- Basic ASCII conversion
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if hi == 0 and lo < 128 then
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out = out .. string.char(lo)
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else
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out = out .. "?"
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end
···
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[7] = "Item Type",
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[8] = "Flags",
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[9] = "Artwork ID",
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-
[10] = "Position"
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[10] = "Position",
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[11] = "Unknown",
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[12] = "Unknown"
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}
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return labels[arg_idx]
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elseif msg_type == 0x4201 then -- MenuFooter
···
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local byte_len = chars * 2
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if len - offset >= 5 + byte_len then
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local str = utf16_to_utf8(buf(offset+5, byte_len))
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tree:add(f_db_field_str, buf(offset+5, byte_len)):set_text(prefix .. ": \"" .. str .. "\"")
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-- Use f_db_field_bin for the highlight range to avoid "trailing stray chars" warning
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-- caused by Wireshark's internal string dissector seeing high-byte nulls.
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tree:add(f_db_field_bin, buf(offset+5, byte_len)):set_text(prefix .. ": \"" .. str .. "\"")
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bytes_consumed = 5 + byte_len
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else
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bytes_consumed = len - offset
···
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-- TCP DB Port Discovery Response
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if (pkt.src_port == 12523 or pkt.dst_port == 12523) and length == 2 then
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-
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local tree = root:add(p_djl, buf(0, 2))
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pkt.cols.protocol = "PDJL (DB Port)"
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tree:add(f_db_port, buf(0, 2))
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return
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end
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+
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if length < 5 then return end