Increase the size of the addresses in protobuf.
Fix layout2.c to handle longer addresses.
Add a field bech32_prefix to coins.h
Adapted the coins-gen script.
Added bech32 support in signing.c and transaction.c
Having CoinType using the protobuf structures has several disadvantages.
- We always need to change trezor-common if we need a new field (like
bech32 prefix)
- Every time Trezor initializes it sends all this information out and
nobody cares.
- The protobuf structures add storage overhead due to their fixed size.
I also removed most of the `has_` fields except for forkid:
- `has_segwit` was merged with segwit
- `has_coin_shortcut` can be replaced by test for NULL if necessary.
The fields were reordered for better padding.
Every 4294967295 milliseconds (2 ^ 32 - 1), system_millis will overflow.
This means that every 49.71 days, system_millis will reset to zero.
Comparisons like `system_millis < (system_millis + 1)` would fail if the
latter had overflown and the former had not.
This is non-critical because the worst case is that one second could be
skipped or the screen could lock early.
This poses no threat to the exponential backoff used for protection
against brute force.
Following ECDH usage of layoutDecryptIdentity (which shows "GPG decrypt for:")
this commit adds a specific case for layoutSignIdentity, showing "GPG sign for:",
instead of "GPG login to:" (which is less appropriate in the GPG context).
U2F doesn't allow cancellation on device.
Also fix button state in protect. This fixes the following bug:
1. wipe device
2. press and hold right button, click left button to cancel.
3. release all buttons.
4. wipe device again, now automatic.
