qr_code.md 2.1 KB
QR Code Format
The QR code contains the necessary information that the app needs to be able to connect to the browser. It consists primarily of the permanent public key and the auth token as required by SaltyRTC. Additionally some configuration flags are being transmitted.
Binary Format
The binary format looks like this:
|VV|O|PPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP|TTTTTTTTTTTTTTTTTTTTTTTTTTTTTTTT|SSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS|NN|HHHHHHHH...|
- V: Version number (2 bytes, UInt16, big endian)
- O: Options bitfield (1 byte)
- P: Initiator permanent public key (32 bytes)
- T: Auth token (32 bytes)
- S: Server permanent public key (32 bytes)
- N: SaltyRTC port (2 bytes, UInt16, big endian)
- H: SaltyRTC host (n bytes, UTF8 String, no null termination)
If you don't want to specify a permanent key for the server, set all bytes to 0.
Options Bitfield
The option bitfields encodes true/false flags. Currently there are two supported flags:
MSB LSB
+---------------+
|0 0 0 0 0 0 P S|
+---------------+
- S: Self-hosted. Set this to 1 if the webclient is self-hosted, or to 0 if
this is the officially hosted version. This only has an influence on
displayed error messages for improved usability.
- P: Whether this session is permanent or not. Set this to 1 if the user
defined a password.
Encoding
The binary data is encoded as Base64. The QR code is then generated in alphanumeric mode.
Example
The following data:
- Version: 1337
- Permanent: true
- Self hosted: false
- Initiator permanent public key: 0x4242424242424242424242424242424242424242424242424242424242424242
- Auth token: 0x2323232323232323232323232323232323232323232323232323232323232323
- Server permanent public key: 0x1337133713371337133713371337133713371337133713371337133713371337
- Host: saltyrtc.example.org
- Port: 1234
...will result in the following Base64 string:
BTkCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkJCQkIjIyMjIyMjIyMjIyMjIyMjIyMjIyMj
IyMjIyMjIyMjIxM3EzcTNxM3EzcTNxM3EzcTNxM3EzcTNxM3EzcTNxM3BNJzYWx0eXJ0Yy5leGFt
cGxlLm9yZw==