Feature #2460

Updated by pespin 12 months ago

Currently the "encryption" parameter lets define which cipher is allowed by MSC, but only one can be allowed at a given time: "encryption a5 (0|1|2|3)"

In AoIP protocol, however, the cipher is negotiated between MSC<->BSC (BSC interesected with BTS and MS capabilities). Once "Authentication Response" reaches MSC with correct challenge response, the MSC sends a "Cipher Mode Command" to the BSC with a bitmask stating the allowed ciphers.

As we currently only set 1 cipher in config, only 1 bit can be enabled at a time in the bitmask, and if that mode doesn't match the one required by BSC/BTS/MS, then BSC will send a Reject and the modem will fail to connect.

We should be able to specify "encryption" parameter either as a bitmask or a list instead of a plain integer, eg:
"encryption a5 0 1 3"
"encryption a5 0x0B" 0x0A" (same as above: 0000 1011) 1010)


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