ecrecover/src/ecrecover_util.erl
2019-08-15 09:28:29 +02:00

29 lines
811 B
Erlang

-module(ecrecover_util).
-export([ recover_from_hex/1
, bin_to_hex/1
, hex_to_bin/1
]).
%%=============================================================================
%% External API
recover_from_hex(Input) ->
<<Hash:32/binary, _:31/binary, Sig:65/binary>> = hex_to_bin(Input),
PubKey = ecrecover:recover(Hash, Sig),
bin_to_hex(PubKey).
bin_to_hex(Bin) ->
lists:flatten([io_lib:format("~2.16.0B", [X]) || X <- binary_to_list(Bin)]).
hex_to_bin(S) ->
hex_to_bin(S, []).
hex_to_bin([], Acc) ->
list_to_binary(lists:reverse(Acc));
hex_to_bin([X,Y|T], Acc) ->
{ok, [V], []} = io_lib:fread("~16u", [X,Y]),
hex_to_bin(T, [V | Acc]);
hex_to_bin([X|T], Acc) ->
{ok, [V], []} = io_lib:fread("~16u", lists:flatten([X,"0"])),
hex_to_bin(T, [V | Acc]).