KDE PIM/KItinerary/MAV Barcode: Difference between revisions

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* String encoding is UTF-8.
* String encoding is UTF-8.
* Number encoding seems big endian.
* Number encoding seems big endian.
* Variable length, observed between 217 and 274 bytes.
* Content has a high amount of null bytes.
* Content has a high amount of null bytes.
* Date/time values are encoded as seconds since Jan 1st 2017. Times are local but do not account for DST. (Exception: traveler birth date).
* Date/time values are encoded as seconds since Jan 1st 2017. Times are local but do not account for DST. (Exception: traveler birth date).
* At least three observed variants, so maybe some kind of (fixed-length?) block structure (but no signs of TLV):
** 217 bytes, personalized train ticket without seat reservation
** 274 bytes, personalized train ticket with seat reservation
** 153 bytes, bike addon ticket


== Layout ==
== Layout ==

Revision as of 13:34, 22 August 2021

General Observation

  • Uses PDF417 barcode format.
  • Variable length.
  • For domestic tickets only.
  • No similarities with a known ERA format.

Outer Structure

  • Two byte header, fixed 0x0403.
  • Gzip-compressed payload using deflate compression, starting with the standard Gzip header 0x1f8b0800000000000000.
  • 256 remaining bytes, high entropy and length suggest a cryptographic signature.

Payload Structure

Note: this is based on very few samples so far and thus isn't very reliable yet!

  • Seems byte- rather than bit-aligned.
  • String encoding is UTF-8.
  • Number encoding seems big endian.
  • Content has a high amount of null bytes.
  • Date/time values are encoded as seconds since Jan 1st 2017. Times are local but do not account for DST. (Exception: traveler birth date).
  • At least three observed variants, so maybe some kind of (fixed-length?) block structure (but no signs of TLV):
    • 217 bytes, personalized train ticket without seat reservation
    • 274 bytes, personalized train ticket with seat reservation
    • 153 bytes, bike addon ticket

Layout

Offset Size Data Type Meaning Notes
0 17 string ticket number printed as "CIV" on the PDF
17 1 null ?
18 2 uint16 UIC company code issuer or carrier, 0x0483 (1155) for MAV
20 4 time issuing time
24 15 ? ?
39 45 string passenger name null terminated
84 4 uint32 passenger birth date year * 10000 + month * 100 + day
88 15 null ? null in all samples
103 4 ? ?
107 3 uint24 UIC departure station code including the national prefix ('55' for HU)
110 3 uint24 UIC arrival station code
113 90 null ? null in all samples
203 1 text class "1" or "2"
204 1 ? ? 0x01 in all samples
205 4 time time of validity/travel
209 8 ? ?
217 3 uint24 UIC departure station code byte 217 and following are only present in tickets with seat reservations
220 3 uint24 UIC arrival station code
223 4 ? ?
227 4 time time of validity/travel same as byte 205
231 2 ? ?
233 5 string train number null-terminated
238 2 ? coach number? numeric or string encoding, too few samples to be sure
240 6 numeric seat number? too few samples to be sure
246 28 null ? null bytes in all samples

Missing/Suspected Information

  • Station names are not included, but station codes might be. UIC station numbers (possibly without the country prefix) would be the obvious suspect, given the MÁV website uses those as well.
  • If the train number is included, one would expect at least the day of travel to be included as well.
  • Class: several candidate locations exist, but given it's small footprint we need a lot more samples to confirm one of those.