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-rw-r--r--lib/ssh/src/ssh_transport.erl266
1 files changed, 82 insertions, 184 deletions
diff --git a/lib/ssh/src/ssh_transport.erl b/lib/ssh/src/ssh_transport.erl
index de3e29e2f1..6140c87f6e 100644
--- a/lib/ssh/src/ssh_transport.erl
+++ b/lib/ssh/src/ssh_transport.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 2004-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2004-2012. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
@@ -23,10 +23,11 @@
-module(ssh_transport).
--include("ssh_transport.hrl").
+-include_lib("public_key/include/public_key.hrl").
+-include_lib("kernel/include/inet.hrl").
+-include("ssh_transport.hrl").
-include("ssh.hrl").
--include_lib("kernel/include/inet.hrl").
-export([connect/5, accept/4]).
-export([versions/2, hello_version_msg/1]).
@@ -38,17 +39,8 @@
handle_kex_dh_gex_group/2, handle_kex_dh_gex_reply/2,
handle_new_keys/2, handle_kex_dh_gex_request/2,
handle_kexdh_reply/2,
- unpack/3, decompress/2, ssh_packet/2, pack/2, msg_data/1]).
-
-%% debug flagso
--define(DBG_ALG, true).
--define(DBG_KEX, true).
--define(DBG_CRYPTO, false).
--define(DBG_PACKET, false).
--define(DBG_MESSAGE, true).
--define(DBG_BIN_MESSAGE, true).
--define(DBG_MAC, false).
--define(DBG_ZLIB, true).
+ unpack/3, decompress/2, ssh_packet/2, pack/2, msg_data/1,
+ sign/3, verify/4]).
versions(client, Options)->
Vsn = proplists:get_value(vsn, Options, ?DEFAULT_CLIENT_VERSION),
@@ -212,24 +204,24 @@ key_exchange_init_msg(Ssh0) ->
{SshPacket, Ssh} = ssh_packet(Msg, Ssh0),
{Msg, SshPacket, Ssh}.
-kex_init(#ssh{role = Role, opts = Opts}) ->
+kex_init(#ssh{role = Role, opts = Opts, available_host_keys = HostKeyAlgs}) ->
Random = ssh_bits:random(16),
Compression = case proplists:get_value(compression, Opts, none) of
zlib -> ["zlib", "none"];
none -> ["none", "zlib"]
end,
- kexinit_messsage(Role, Random, Compression).
+ kexinit_messsage(Role, Random, Compression, HostKeyAlgs).
key_init(client, Ssh, Value) ->
Ssh#ssh{c_keyinit = Value};
key_init(server, Ssh, Value) ->
Ssh#ssh{s_keyinit = Value}.
-kexinit_messsage(client, Random, Compression) ->
+kexinit_messsage(client, Random, Compression, HostKeyAlgs) ->
#ssh_msg_kexinit{
cookie = Random,
kex_algorithms = ["diffie-hellman-group1-sha1"],
- server_host_key_algorithms = ["ssh-rsa", "ssh-dss"],
+ server_host_key_algorithms = HostKeyAlgs,
encryption_algorithms_client_to_server = ["aes128-cbc","3des-cbc"],
encryption_algorithms_server_to_client = ["aes128-cbc","3des-cbc"],
mac_algorithms_client_to_server = ["hmac-sha1"],
@@ -240,11 +232,11 @@ kexinit_messsage(client, Random, Compression) ->
languages_server_to_client = []
};
-kexinit_messsage(server, Random, Compression) ->
+kexinit_messsage(server, Random, Compression, HostKeyAlgs) ->
#ssh_msg_kexinit{
cookie = Random,
kex_algorithms = ["diffie-hellman-group1-sha1"],
- server_host_key_algorithms = ["ssh-dss"],
+ server_host_key_algorithms = HostKeyAlgs,
encryption_algorithms_client_to_server = ["aes128-cbc","3des-cbc"],
encryption_algorithms_server_to_client = ["aes128-cbc","3des-cbc"],
mac_algorithms_client_to_server = ["hmac-sha1"],
@@ -300,7 +292,6 @@ install_messages('diffie-hellman-group-exchange-sha1') ->
key_exchange_first_msg('diffie-hellman-group1-sha1', Ssh0) ->
{G, P} = dh_group1(),
{Private, Public} = dh_gen_key(G, P, 1024),
- %%?dbg(?DBG_KEX, "public: ~p~n", [Public]),
{SshPacket, Ssh1} = ssh_packet(#ssh_msg_kexdh_init{e = Public}, Ssh0),
{ok, SshPacket,
Ssh1#ssh{keyex_key = {{Private, Public}, {G, P}}}};
@@ -320,7 +311,6 @@ key_exchange_first_msg('diffie-hellman-group-exchange-sha1', Ssh0) ->
handle_kexdh_init(#ssh_msg_kexdh_init{e = E}, Ssh0) ->
{G, P} = dh_group1(),
{Private, Public} = dh_gen_key(G, P, 1024),
- %%?dbg(?DBG_KEX, "public: ~p~n", [Public]),
K = ssh_math:ipow(E, Private, P),
{Key, K_S} = get_host_key(Ssh0),
H = kex_h(Ssh0, K_S, E, Public, K),
@@ -329,8 +319,7 @@ handle_kexdh_init(#ssh_msg_kexdh_init{e = E}, Ssh0) ->
f = Public,
h_sig = H_SIG
}, Ssh0),
- %%?dbg(?DBG_KEX, "shared_secret: ~s ~n", [fmt_binary(K, 16, 4)]),
- %%?dbg(?DBG_KEX, "hash: ~s ~n", [fmt_binary(H, 16, 4)]),
+
{ok, SshPacket, Ssh1#ssh{keyex_key = {{Private, Public}, {G, P}},
shared_secret = K,
exchanged_hash = H,
@@ -338,7 +327,6 @@ handle_kexdh_init(#ssh_msg_kexdh_init{e = E}, Ssh0) ->
handle_kex_dh_gex_group(#ssh_msg_kex_dh_gex_group{p = P, g = G}, Ssh0) ->
{Private, Public} = dh_gen_key(G,P,1024),
- %%?dbg(?DBG_KEX, "public: ~p ~n", [Public]),
{SshPacket, Ssh1} =
ssh_packet(#ssh_msg_kex_dh_gex_init{e = Public}, Ssh0),
{ok, SshPacket,
@@ -362,8 +350,7 @@ handle_kexdh_reply(#ssh_msg_kexdh_reply{public_host_key = HostKey, f = F,
#ssh{keyex_key = {{Private, Public}, {_G, P}}} = Ssh0) ->
K = ssh_math:ipow(F, Private, P),
H = kex_h(Ssh0, HostKey, Public, F, K),
- %%?dbg(?DBG_KEX, "shared_secret: ~s ~n", [fmt_binary(K, 16, 4)]),
- %%?dbg(?DBG_KEX, "hash: ~s ~n", [fmt_binary(H, 16, 4)]),
+
case verify_host_key(Ssh0, HostKey, H, H_SIG) of
ok ->
{SshPacket, Ssh} = ssh_packet(#ssh_msg_newkeys{}, Ssh0),
@@ -396,8 +383,7 @@ handle_kex_dh_gex_reply(#ssh_msg_kex_dh_gex_reply{public_host_key = HostKey,
Ssh0) ->
K = ssh_math:ipow(F, Private, P),
H = kex_h(Ssh0, HostKey, Min, NBits, Max, P, G, Public, F, K),
- %%?dbg(?DBG_KEX, "shared_secret: ~s ~n", [fmt_binary(K, 16, 4)]),
- %%?dbg(?DBG_KEX, "hash: ~s ~n", [fmt_binary(H, 16, 4)]),
+
case verify_host_key(Ssh0, HostKey, H, H_SIG) of
ok ->
{SshPacket, Ssh} = ssh_packet(#ssh_msg_newkeys{}, Ssh0),
@@ -423,83 +409,68 @@ sid(#ssh{session_id = Id}, _) ->
%%
get_host_key(SSH) ->
#ssh{key_cb = Mod, opts = Opts, algorithms = ALG} = SSH,
- Scope = proplists:get_value(key_scope, Opts, system),
- case ALG#alg.hkey of
- 'ssh-rsa' ->
- case Mod:private_host_rsa_key(Scope, Opts) of
- {ok,Key=#ssh_key { public={N,E}} } ->
- %%?dbg(true, "x~n", []),
- {Key,
- ssh_bits:encode(["ssh-rsa",E,N],[string,mpint,mpint])};
- Error ->
- %%?dbg(true, "y~n", []),
- exit(Error)
- end;
- 'ssh-dss' ->
- case Mod:private_host_dsa_key(Scope, Opts) of
- {ok,Key=#ssh_key { public={P,Q,G,Y}}} ->
- {Key, ssh_bits:encode(["ssh-dss",P,Q,G,Y],
- [string,mpint,mpint,mpint,mpint])};
- Error ->
- exit(Error)
- end;
- _ ->
- exit({error, bad_key_type})
+
+ case Mod:host_key(ALG#alg.hkey, Opts) of
+ {ok, #'RSAPrivateKey'{modulus = N, publicExponent = E} = Key} ->
+ {Key,
+ ssh_bits:encode(["ssh-rsa",E,N],[string,mpint,mpint])};
+ {ok, #'DSAPrivateKey'{y = Y, p = P, q = Q, g = G} = Key} ->
+ {Key, ssh_bits:encode(["ssh-dss",P,Q,G,Y],
+ [string,mpint,mpint,mpint,mpint])};
+ Result ->
+ exit({error, {Result, unsupported_key_type}})
end.
-sign_host_key(Ssh, Private, H) ->
- ALG = Ssh#ssh.algorithms,
- Module = case ALG#alg.hkey of
- 'ssh-rsa' ->
- ssh_rsa;
- 'ssh-dss' ->
- ssh_dsa
- end,
- case catch Module:sign(Private, H) of
- {'EXIT', Reason} ->
- error_logger:format("SIGN FAILED: ~p\n", [Reason]),
- {error, Reason};
- SIG ->
- ssh_bits:encode([Module:alg_name() ,SIG],[string,binary])
- end.
+sign_host_key(_Ssh, #'RSAPrivateKey'{} = Private, H) ->
+ Hash = sha, %% Option ?!
+ Signature = sign(H, Hash, Private),
+ ssh_bits:encode(["ssh-rsa", Signature],[string, binary]);
+sign_host_key(_Ssh, #'DSAPrivateKey'{} = Private, H) ->
+ Hash = sha, %% Option ?!
+ RawSignature = sign(H, Hash, Private),
+ ssh_bits:encode(["ssh-dss", RawSignature],[string, binary]).
verify_host_key(SSH, K_S, H, H_SIG) ->
ALG = SSH#ssh.algorithms,
case ALG#alg.hkey of
'ssh-rsa' ->
- case ssh_bits:decode(K_S,[string,mpint,mpint]) of
- ["ssh-rsa", E, N] ->
- ["ssh-rsa",SIG] = ssh_bits:decode(H_SIG,[string,binary]),
- Public = #ssh_key { type=rsa, public={N,E} },
- case catch ssh_rsa:verify(Public, H, SIG) of
- {'EXIT', Reason} ->
- error_logger:format("VERIFY FAILED: ~p\n", [Reason]),
- {error, bad_signature};
- ok ->
- known_host_key(SSH, Public, "ssh-rsa")
- end;
- _ ->
- {error, bad_format}
- end;
+ verify_host_key_rsa(SSH, K_S, H, H_SIG);
'ssh-dss' ->
- case ssh_bits:decode(K_S,[string,mpint,mpint,mpint,mpint]) of
- ["ssh-dss",P,Q,G,Y] ->
- ["ssh-dss",SIG] = ssh_bits:decode(H_SIG,[string,binary]),
- Public = #ssh_key { type=dsa, public={P,Q,G,Y} },
- case catch ssh_dsa:verify(Public, H, SIG) of
- {'EXIT', Reason} ->
- error_logger:format("VERIFY FAILED: ~p\n", [Reason]),
- {error, bad_signature};
- ok ->
- known_host_key(SSH, Public, "ssh-dss")
- end;
- _ ->
- {error, bad_host_key_format}
- end;
+ verify_host_key_dss(SSH, K_S, H, H_SIG);
_ ->
{error, bad_host_key_algorithm}
end.
+verify_host_key_rsa(SSH, K_S, H, H_SIG) ->
+ case ssh_bits:decode(K_S,[string,mpint,mpint]) of
+ ["ssh-rsa", E, N] ->
+ ["ssh-rsa",SIG] = ssh_bits:decode(H_SIG,[string,binary]),
+ Public = #'RSAPublicKey'{publicExponent = E, modulus = N},
+ case verify(H, sha, SIG, Public) of
+ false ->
+ {error, bad_signature};
+ true ->
+ known_host_key(SSH, Public, "ssh-rsa")
+ end;
+ _ ->
+ {error, bad_format}
+ end.
+
+verify_host_key_dss(SSH, K_S, H, H_SIG) ->
+ case ssh_bits:decode(K_S,[string,mpint,mpint,mpint,mpint]) of
+ ["ssh-dss",P,Q,G,Y] ->
+ ["ssh-dss",SIG] = ssh_bits:decode(H_SIG,[string,binary]),
+ Public = {Y, #'Dss-Parms'{p = P, q = Q, g = G}},
+ case verify(H, sha, SIG, Public) of
+ false ->
+ {error, bad_signature};
+ true ->
+ known_host_key(SSH, Public, "ssh-dss")
+ end;
+ _ ->
+ {error, bad_host_key_format}
+ end.
+
accepted_host(Ssh, PeerName, Opts) ->
case proplists:get_value(silently_accept_hosts, Opts, false) of
true ->
@@ -511,14 +482,10 @@ accepted_host(Ssh, PeerName, Opts) ->
known_host_key(#ssh{opts = Opts, key_cb = Mod, peer = Peer} = Ssh,
Public, Alg) ->
PeerName = peer_name(Peer),
- case Mod:lookup_host_key(PeerName, Alg, Opts) of
- {ok, Public} ->
+ case Mod:is_host_key(Public, PeerName, Alg, Opts) of
+ true ->
ok;
- {ok, BadPublic} ->
- error_logger:format("known_host_key: Public ~p BadPublic ~p\n",
- [Public, BadPublic]),
- {error, bad_public_key};
- {error, not_found} ->
+ false ->
case accepted_host(Ssh, PeerName, Opts) of
yes ->
Mod:add_host_key(PeerName, Public, Opts);
@@ -621,7 +588,6 @@ install_alg(SSH) ->
alg_setup(SSH) ->
ALG = SSH#ssh.algorithms,
- %%?dbg(?DBG_ALG, "ALG: setup ~p ~n", [ALG]),
SSH#ssh{kex = ALG#alg.kex,
hkey = ALG#alg.hkey,
encrypt = ALG#alg.encrypt,
@@ -638,7 +604,6 @@ alg_setup(SSH) ->
}.
alg_init(SSH0) ->
- %%?dbg(?DBG_ALG, "ALG: init~n", []),
{ok,SSH1} = send_mac_init(SSH0),
{ok,SSH2} = recv_mac_init(SSH1),
{ok,SSH3} = encrypt_init(SSH2),
@@ -648,7 +613,6 @@ alg_init(SSH0) ->
SSH6.
alg_final(SSH0) ->
- %%?dbg(?DBG_ALG, "ALG: final ~n", []),
{ok,SSH1} = send_mac_final(SSH0),
{ok,SSH2} = recv_mac_final(SSH1),
{ok,SSH3} = encrypt_final(SSH2),
@@ -669,19 +633,15 @@ select(CL, SL) ->
[] -> undefined;
[ALG|_] -> ALG
end,
- %%?dbg(?DBG_ALG, "ALG: select: ~p ~p = ~p~n", [CL, SL, C]),
C.
ssh_packet(#ssh_msg_kexinit{} = Msg, Ssh0) ->
BinMsg = ssh_bits:encode(Msg),
Ssh = key_init(Ssh0#ssh.role, Ssh0, BinMsg),
- %%?dbg(?DBG_MESSAGE, "SEND_MSG: ~p~n", [Msg]),
pack(BinMsg, Ssh);
ssh_packet(Msg, Ssh) ->
BinMsg = ssh_bits:encode(Msg),
- %%?dbg(?DBG_MESSAGE, "SEND_MSG: ~p~n", [Msg]),
- %%?dbg(?DBG_BIN_MESSAGE, "Encoded: ~p~n", [BinMsg]),
pack(BinMsg, Ssh).
pack(Data0, #ssh{encrypt_block_size = BlockSize,
@@ -732,17 +692,20 @@ msg_data(PacketData) ->
_:PaddingLen/binary>> = PacketData,
Data.
+sign(SigData, Hash, #'DSAPrivateKey'{} = Key) ->
+ DerSignature = public_key:sign(SigData, Hash, Key),
+ #'Dss-Sig-Value'{r = R, s = S} = public_key:der_decode('Dss-Sig-Value', DerSignature),
+ <<R:160/big-unsigned-integer, S:160/big-unsigned-integer>>;
+sign(SigData, Hash, Key) ->
+ public_key:sign(SigData, Hash, Key).
-%% Send a disconnect message
-%% terminate(S, SSH, Code, Message) ->
-%% M = #ssh_msg_disconnect{code=Code,
-%% description = Message,
-%% language = "en"},
-%% send_msg(S, SSH, M),
-%% gen_tcp:close(S),
-%% {error, M}.
+verify(PlainText, Hash, Sig, {_, #'Dss-Parms'{}} = Key) ->
+ <<R:160/big-unsigned-integer, S:160/big-unsigned-integer>> = Sig,
+ Signature = public_key:der_encode('Dss-Sig-Value', #'Dss-Sig-Value'{r = R, s = S}),
+ public_key:verify(PlainText, Hash, Signature, Key);
+verify(PlainText, Hash, Sig, Key) ->
+ public_key:verify(PlainText, Hash, Sig, Key).
-
%% public key algorithms
%%
%% ssh-dss REQUIRED sign Raw DSS Key
@@ -761,9 +724,6 @@ msg_data(PacketData) ->
%%
%%
-
-
-
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Encryption
%%
@@ -833,19 +793,13 @@ encrypt(#ssh{encrypt = none} = Ssh, Data) ->
encrypt(#ssh{encrypt = '3des-cbc',
encrypt_keys = {K1,K2,K3},
encrypt_ctx = IV0} = Ssh, Data) ->
- %%?dbg(?DBG_CRYPTO, "encrypt: IV=~p K1=~p, K2=~p, K3=~p ~n",
- %% [IV0,K1,K2,K3]),
Enc = crypto:des3_cbc_encrypt(K1,K2,K3,IV0,Data),
- %%?dbg(?DBG_CRYPTO, "encrypt: ~p -> ~p ~n", [Data, Enc]),
IV = crypto:des_cbc_ivec(Enc),
{Ssh#ssh{encrypt_ctx = IV}, Enc};
encrypt(#ssh{encrypt = 'aes128-cbc',
encrypt_keys = K,
encrypt_ctx = IV0} = Ssh, Data) ->
- %%?dbg(?DBG_CRYPTO, "encrypt: IV=~p K=~p ~n",
- %% [IV0,K]),
Enc = crypto:aes_cbc_128_encrypt(K,IV0,Data),
- %%?dbg(?DBG_CRYPTO, "encrypt: ~p -> ~p ~n", [Data, Enc]),
IV = crypto:aes_cbc_ivec(Enc),
{Ssh#ssh{encrypt_ctx = IV}, Enc}.
@@ -893,18 +847,12 @@ decrypt(#ssh{decrypt = none} = Ssh, Data) ->
decrypt(#ssh{decrypt = '3des-cbc', decrypt_keys = Keys,
decrypt_ctx = IV0} = Ssh, Data) ->
{K1, K2, K3} = Keys,
- %%?dbg(?DBG_CRYPTO, "decrypt: IV=~p K1=~p, K2=~p, K3=~p ~n",
- %%[IV0,K1,K2,K3]),
Dec = crypto:des3_cbc_decrypt(K1,K2,K3,IV0,Data),
- %%?dbg(?DBG_CRYPTO, "decrypt: ~p -> ~p ~n", [Data, Dec]),
IV = crypto:des_cbc_ivec(Data),
{Ssh#ssh{decrypt_ctx = IV}, Dec};
decrypt(#ssh{decrypt = 'aes128-cbc', decrypt_keys = Key,
decrypt_ctx = IV0} = Ssh, Data) ->
- %%?dbg(?DBG_CRYPTO, "decrypt: IV=~p Key=~p ~n",
- %% [IV0,Key]),
Dec = crypto:aes_cbc_128_decrypt(Key,IV0,Data),
- %%?dbg(?DBG_CRYPTO, "decrypt: ~p -> ~p ~n", [Data, Dec]),
IV = crypto:aes_cbc_ivec(Data),
{Ssh#ssh{decrypt_ctx = IV}, Dec}.
@@ -936,7 +884,6 @@ compress(#ssh{compress = none} = Ssh, Data) ->
{Ssh, Data};
compress(#ssh{compress = zlib, compress_ctx = Context} = Ssh, Data) ->
Compressed = zlib:deflate(Context, Data, sync),
- %%?dbg(?DBG_ZLIB, "deflate: ~p -> ~p ~n", [Data, Compressed]),
{Ssh, list_to_binary(Compressed)}.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -960,7 +907,6 @@ decompress(#ssh{decompress = none} = Ssh, Data) ->
{Ssh, Data};
decompress(#ssh{decompress = zlib, decompress_ctx = Context} = Ssh, Data) ->
Decompressed = zlib:inflate(Context, Data),
- %%?dbg(?DBG_ZLIB, "inflate: ~p -> ~p ~n", [Data, Decompressed]),
{Ssh, list_to_binary(Decompressed)}.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -1039,7 +985,6 @@ hash(SSH, Char, N, HASH) ->
K1 = HASH([K, H, Char, SessionID]),
Sz = N div 8,
<<Key:Sz/binary, _/binary>> = hash(K, H, K1, N-128, HASH),
- %%?dbg(?DBG_KEX, "Key ~s: ~s ~n", [Char, fmt_binary(Key, 16, 4)]),
Key.
hash(_K, _H, Ki, N, _HASH) when N =< 0 ->
@@ -1055,6 +1000,7 @@ kex_h(SSH, K_S, E, F, K) ->
[string,string,binary,binary,binary,
mpint,mpint,mpint]),
crypto:sha(L).
+
kex_h(SSH, K_S, Min, NBits, Max, Prime, Gen, E, F, K) ->
L = if Min==-1; Max==-1 ->
@@ -1075,7 +1021,7 @@ kex_h(SSH, K_S, Min, NBits, Max, Prime, Gen, E, F, K) ->
Prime, Gen, E,F,K], Ts)
end,
crypto:sha(L).
-
+
mac_key_size('hmac-sha1') -> 20*8;
mac_key_size('hmac-sha1-96') -> 20*8;
mac_key_size('hmac-md5') -> 16*8;
@@ -1105,9 +1051,6 @@ dh_gen_key(G, P, _Bits) ->
Public = ssh_math:ipow(G, Private, P),
{Private,Public}.
-%% trim(Str) ->
-%% lists:reverse(trim_head(lists:reverse(trim_head(Str)))).
-
trim_tail(Str) ->
lists:reverse(trim_head(lists:reverse(Str))).
@@ -1116,48 +1059,3 @@ trim_head([$\t|Cs]) -> trim_head(Cs);
trim_head([$\n|Cs]) -> trim_head(Cs);
trim_head([$\r|Cs]) -> trim_head(Cs);
trim_head(Cs) -> Cs.
-
-%% Retrieve session_id from ssh, needed by public-key auth
-%get_session_id(SSH) ->
-% {ok, SessionID} = call(SSH, get_session_id),
-
-%% DEBUG utils
-%% Format integers and binaries as hex blocks
-%%
-%% -ifdef(debug).
-%% fmt_binary(B, BlockSize, GroupSize) ->
-%% fmt_block(fmt_bin(B), BlockSize, GroupSize).
-
-%% fmt_block(Bin, BlockSize, GroupSize) ->
-%% fmt_block(Bin, BlockSize, 0, GroupSize).
-
-
-%% fmt_block(Bin, 0, _I, _G) ->
-%% binary_to_list(Bin);
-%% fmt_block(Bin, Sz, G, G) when G =/= 0 ->
-%% ["~n#" | fmt_block(Bin, Sz, 0, G)];
-%% fmt_block(Bin, Sz, I, G) ->
-%% case Bin of
-%% <<Block:Sz/binary, Tail/binary>> ->
-%% if Tail == <<>> ->
-%% [binary_to_list(Block)];
-%% true ->
-%% [binary_to_list(Block), " " | fmt_block(Tail, Sz, I+1, G)]
-%% end;
-%% <<>> ->
-%% [];
-%% _ ->
-%% [binary_to_list(Bin)]
-%% end.
-
-%% %% Format integer or binary as hex
-%% fmt_bin(X) when integer(X) ->
-%% list_to_binary(io_lib:format("~p", [X]));
-%% fmt_bin(X) when binary(X) ->
-%% Sz = size(X)*8,
-%% <<Y:Sz/unsigned-big>> = X,
-%% %%Fmt = "~"++integer_to_list(size(X)*2)++"~p",
-%% list_to_binary(io_lib:format("~p", [Y])).
-
-%% -endif.
-