KDE PIM/KItinerary/Thalys Barcode

From KDE Community Wiki

General Observations

  • always exactly 114 byte
  • there's two 14-15 byte variable lengths blocks towards the end with very high entropy, possibly some kind of signature
  • 0:4 - 2:1 (14 bit) is "3018", which is the UIC operator code of Thalys. This matches Appendix C of ANNEX B.6 of TAP TSI, but unfortunately only for the first 18 bit it seems. Might still mean a similar encoding is used, but in a different layout.
  • all expected data has been located, but not the date/time?
  • This does seem to largely match what is described in "European Union Agency For Railways - Technical Document - Digital Security Elements For Rail Passenger Ticketing - $7 SSB - Small Structured Barcode"

Bit Layout

Byte[:Bit] (MSB) Content Meaning Notes
0:0 - 4:7 0x32 F2 84 20 40 fixed in all samples
5:0 - 5:7 0x01 or 0x02 class
6:0 - 9:5 null
9:6 - 16:3 9 x 6bit string ticket number
16:4 - 18:3 TODO
18:4 - 22:1 5 x 6bit string departure station see below
22:2 - 25:7 5 x 6bit string arrival station see below
26:0 - 27:7 TODO
28:0 - 29:1 null
29:2 - 32:1 4 x 6bit string train number preceding bits might be a 5th character for this
32:2 - 33:3 9bit uint coach number field seems a bit large for this?
33:4 - 35:5 3 x 6bit string seat number
35:6 - 42:6 null
42:7 - 55:4 17 x 6 bit string CIN 17 digit number, also seen on some PDF tickets, possibly sequential, common prefix "3084060" in all samples
55:5 - 55:7 TODO
56:0 - 58:7 0x0a 80 30 same TLV/BER/DER-like nested signature block as used by KDE_PIM/KItinerary/SBB_Barcode, 0x80 would be a null-terminated variable length block according to BER
59:0 - 59:7 1 byte length of the following data 0x2C or 0x2E in current samples

After this there follow two blocks with the following variable length layout:

Byte[:Bit] (MSB) Content Meaning Notes
0:0 - 0:7 0x02 fixed
1:0 - 1:7 8bit uint length
N bytes high entropy content

Remaining bytes are filled by null until reaching 114 bytes.

Strings:

  • encoded as 6bit per character
  • a character can be converted to the corresponding ASCII value by adding 32

Station identifiers:

  • using Benerail identifiers, which consists of 5 upper-case letters, the first two being the ISO 3166-1 alpha 2 code
  • very similar to SNCF identifiers, but there are slight differences e.g. for Amsterdam Central (NLASC vs NLAMA).