Change strMessageMagic to not collide with Bitcoin

[prusnak]

Value of strMessageMagic is set to "Bitcoin Signed Message:\n", this does not make sense as it collides with Bitcoin.

See https://github.com/particl/particl-core/blob/master/src/util/validation.cpp#L19

Please change it to something else.

[kewde]

@prusnak
Mind giving a bit more context? Are there any security concerns that may affect the Trezor security model?

As far as I can tell, if the key derivation happens on the right path, then I presume things should remain secure, but I do understand that it's a bit off to use the same header.

@tecnovert

I'm not exactly sure but changing this header will have implications for the SMSG service right?

[prusnak]

As far as I can tell, if the key derivation happens on the right path, then I presume things should remain secure, but I do understand that it's a bit off to use the same header.

This is valid argument for Trezor, but not for the others. For example, does your own code check whether the path used for signing starts with m/44'/44'?

[kewde]

@prusnak our core application does not store the master seed by default.
We store m/44'/44' rather than m by default.
https://github.com/particl/particl-core/blob/master/src/wallet/rpchdwallet.cpp#L1588

But this may not hold up for other wallets, so I understand the concern.