KDE PIM/KItinerary/vr.fi Barcode: Difference between revisions
< KDE PIM | KItinerary
| Line 23: | Line 23: | ||
| 4:7 - 5:7 || 9 bit day number || || day of travel, counted from Jan 1 | | 4:7 - 5:7 || 9 bit day number || || day of travel, counted from Jan 1 | ||
|- | |- | ||
| 6 - 12 || 0x00 0x49 0x24 0x92 0x49 0x24 0x92 || || fixed in all samples | | 6 - 12 || 0x00 0x49 0x24 0x92 0x49 0x24 0x92 || || fixed in all samples | ||
|- | |- | ||
| 13 - | | 13 - 42:0 || todo || todo || | ||
|- | |||
| 42:1 - 106:0 || 64 byte varying || || high entropy in all samples, signature? | |||
|- | |||
| 106:1 - 106:7 || null || || | |||
|- | |- | ||
|} | |} | ||
Revision as of 17:02, 4 January 2020
General Observations
- always exactly 107 byte
- all binary, there are no recognizable ASCII strings in this
- the last ~64 byte have very high entropy, suggesting a signature or a compressed section
- there's a base64 encoded sequential number printed below the Aztec code on the ticket, containing 24bit.
- one barcode seems to be exactly for one journey section
Bit Layout
| Byte[:Bit] (MSB) | Content | Meaning | Notes |
|---|---|---|---|
| 0 - 1 | 0b0001 0000 0b0000 0010 | unknown | fixed in all samples |
| 2 | 0b1010 0000 or 0b1000 0000 | unknown | |
| 3 | 0b0000 0001 | unknown | fixed in all samples |
| 4:0 4:6 | null | ||
| 4:7 - 5:7 | 9 bit day number | day of travel, counted from Jan 1 | |
| 6 - 12 | 0x00 0x49 0x24 0x92 0x49 0x24 0x92 | fixed in all samples | |
| 13 - 42:0 | todo | todo | |
| 42:1 - 106:0 | 64 byte varying | high entropy in all samples, signature? | |
| 106:1 - 106:7 | null |