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-rw-r--r--lib/ssh/src/ssh_transport.erl409
1 files changed, 298 insertions, 111 deletions
diff --git a/lib/ssh/src/ssh_transport.erl b/lib/ssh/src/ssh_transport.erl
index f4e6a23a1e..38a0b7ec7c 100644
--- a/lib/ssh/src/ssh_transport.erl
+++ b/lib/ssh/src/ssh_transport.erl
@@ -39,7 +39,7 @@
key_exchange_init_msg/1,
key_init/3, new_keys_message/1,
handle_kexinit_msg/3, handle_kexdh_init/2,
- handle_kex_dh_gex_group/2, handle_kex_dh_gex_reply/2,
+ handle_kex_dh_gex_group/2, handle_kex_dh_gex_init/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,
@@ -66,6 +66,8 @@ algo_classes() -> [kex, public_key, cipher, mac, compression].
default_algorithms(compression) ->
%% Do not announce '[email protected]' because there seem to be problems
supported_algorithms(compression, same(['[email protected]']));
+default_algorithms(kex) ->
+ supported_algorithms(kex, []);
default_algorithms(Alg) ->
supported_algorithms(Alg).
@@ -73,23 +75,29 @@ default_algorithms(Alg) ->
supported_algorithms() -> [{K,supported_algorithms(K)} || K <- algo_classes()].
supported_algorithms(kex) ->
- ['diffie-hellman-group1-sha1'];
+ select_crypto_supported(
+ [{'diffie-hellman-group14-sha1', [{hashs,sha}]},
+ {'diffie-hellman-group1-sha1', [{hashs,sha}]},
+ {'diffie-hellman-group-exchange-sha256', [{hashs,sha256}]},
+ {'diffie-hellman-group-exchange-sha1', [{hashs,sha}]}
+ ]);
supported_algorithms(public_key) ->
ssh_auth:default_public_key_algorithms();
supported_algorithms(cipher) ->
- Supports = crypto:supports(),
- CipherAlgos = [{aes_ctr, 'aes128-ctr'}, {aes_cbc128, 'aes128-cbc'}, {des3_cbc, '3des-cbc'}],
- Algs = [SshAlgo ||
- {CryptoAlgo, SshAlgo} <- CipherAlgos,
- lists:member(CryptoAlgo, proplists:get_value(ciphers, Supports, []))],
- same(Algs);
+ same(
+ select_crypto_supported(
+ [{'aes128-ctr', [{ciphers,aes_ctr}]},
+ {'aes128-cbc', [{ciphers,aes_cbc128}]},
+ {'3des-cbc', [{ciphers,des3_cbc}]}
+ ]
+ ));
supported_algorithms(mac) ->
- Supports = crypto:supports(),
- HashAlgos = [{sha256, 'hmac-sha2-256'}, {sha, 'hmac-sha1'}],
- Algs = [SshAlgo ||
- {CryptoAlgo, SshAlgo} <- HashAlgos,
- lists:member(CryptoAlgo, proplists:get_value(hashs, Supports, []))],
- same(Algs);
+ same(
+ select_crypto_supported(
+ [{'hmac-sha2-256', [{hashs,sha256}]},
+ {'hmac-sha1', [{hashs,sha}]}
+ ]
+ ));
supported_algorithms(compression) ->
same(['none','zlib','[email protected]']).
@@ -100,7 +108,15 @@ supported_algorithms(Key, [{client2server,BL1},{server2client,BL2}]) ->
supported_algorithms(Key, BlackList) ->
supported_algorithms(Key) -- BlackList.
-
+select_crypto_supported(L) ->
+ Sup = crypto:supports(),
+ [Name || {Name,CryptoRequires} <- L,
+ crypto_supported(CryptoRequires, Sup)].
+
+crypto_supported(Conditions, Supported) ->
+ lists:all(fun({Tag,CryptoName}) ->
+ lists:member(CryptoName, proplists:get_value(Tag,Supported,[]))
+ end, Conditions).
same(Algs) -> [{client2server,Algs}, {server2client,Algs}].
@@ -135,7 +151,7 @@ ssh_vsn() ->
_:_ -> ""
end.
-random_id(Nlo, Nup) ->
+random_id(Nlo, Nup) ->
[crypto:rand_uniform($a,$z+1) || _<- lists:duplicate(crypto:rand_uniform(Nlo,Nup+1),x) ].
hello_version_msg(Data) ->
@@ -144,7 +160,7 @@ hello_version_msg(Data) ->
next_seqnum(SeqNum) ->
(SeqNum + 1) band 16#ffffffff.
-decrypt_first_block(Bin, #ssh{decrypt_block_size = BlockSize} = Ssh0) ->
+decrypt_first_block(Bin, #ssh{decrypt_block_size = BlockSize} = Ssh0) ->
<<EncBlock:BlockSize/binary, EncData/binary>> = Bin,
{Ssh, <<?UINT32(PacketLen), _/binary>> = DecData} =
decrypt(Ssh0, EncBlock),
@@ -246,52 +262,83 @@ handle_kexinit_msg(#ssh_msg_kexinit{} = CounterPart, #ssh_msg_kexinit{} = Own,
Ssh0#ssh{algorithms = Algoritms});
_ ->
%% TODO: Correct code?
- throw(#ssh_msg_disconnect{code = ?SSH_DISCONNECT_PROTOCOL_ERROR,
+ throw(#ssh_msg_disconnect{code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
description = "Selection of key exchange"
" algorithm failed",
- language = "en"})
+ language = ""})
end;
handle_kexinit_msg(#ssh_msg_kexinit{} = CounterPart, #ssh_msg_kexinit{} = Own,
#ssh{role = server} = Ssh) ->
{ok, Algoritms} = select_algorithm(server, CounterPart, Own),
- {ok, Ssh#ssh{algorithms = Algoritms}}.
+ case verify_algorithm(Algoritms) of
+ true ->
+ {ok, Ssh#ssh{algorithms = Algoritms}};
+ _ ->
+ throw(#ssh_msg_disconnect{code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Selection of key exchange"
+ " algorithm failed",
+ language = ""})
+ end.
%% TODO: diffie-hellman-group14-sha1 should also be supported.
%% Maybe check more things ...
-verify_algorithm(#alg{kex = 'diffie-hellman-group1-sha1'}) ->
- true;
-verify_algorithm(#alg{kex = 'diffie-hellman-group-exchange-sha1'}) ->
- true;
-verify_algorithm(_) ->
- false.
-key_exchange_first_msg('diffie-hellman-group1-sha1', Ssh0) ->
- {G, P} = dh_group1(),
+verify_algorithm(#alg{kex = undefined}) -> false;
+verify_algorithm(#alg{hkey = undefined}) -> false;
+verify_algorithm(#alg{send_mac = undefined}) -> false;
+verify_algorithm(#alg{recv_mac = undefined}) -> false;
+verify_algorithm(#alg{encrypt = undefined}) -> false;
+verify_algorithm(#alg{decrypt = undefined}) -> false;
+verify_algorithm(#alg{compress = undefined}) -> false;
+verify_algorithm(#alg{decompress = undefined}) -> false;
+
+verify_algorithm(#alg{kex = 'diffie-hellman-group1-sha1'}) -> true;
+verify_algorithm(#alg{kex = 'diffie-hellman-group14-sha1'}) -> true;
+verify_algorithm(#alg{kex = 'diffie-hellman-group-exchange-sha1'}) -> true;
+verify_algorithm(#alg{kex = 'diffie-hellman-group-exchange-sha256'}) -> true;
+verify_algorithm(_) -> false.
+
+%%%----------------------------------------------------------------
+%%%
+%%% Key exchange initialization
+%%%
+key_exchange_first_msg(Kex, Ssh0) when Kex == 'diffie-hellman-group1-sha1' ;
+ Kex == 'diffie-hellman-group14-sha1' ->
+ {G, P} = dh_group(Kex),
{Private, Public} = dh_gen_key(G, P, 1024),
+ %% Public = G^Private mod P (def)
{SshPacket, Ssh1} = ssh_packet(#ssh_msg_kexdh_init{e = Public}, Ssh0),
{ok, SshPacket,
Ssh1#ssh{keyex_key = {{Private, Public}, {G, P}}}};
-key_exchange_first_msg('diffie-hellman-group-exchange-sha1', Ssh0) ->
+key_exchange_first_msg(Kex, Ssh0) when Kex == 'diffie-hellman-group-exchange-sha1' ;
+ Kex == 'diffie-hellman-group-exchange-sha256' ->
Min = ?DEFAULT_DH_GROUP_MIN,
NBits = ?DEFAULT_DH_GROUP_NBITS,
Max = ?DEFAULT_DH_GROUP_MAX,
{SshPacket, Ssh1} =
ssh_packet(#ssh_msg_kex_dh_gex_request{min = Min,
- n = NBits, max = Max},
+ n = NBits,
+ max = Max},
Ssh0),
{ok, SshPacket,
Ssh1#ssh{keyex_info = {Min, Max, NBits}}}.
-
-handle_kexdh_init(#ssh_msg_kexdh_init{e = E}, Ssh0) ->
- {G, P} = dh_group1(),
+%%%----------------------------------------------------------------
+%%%
+%%% diffie-hellman-group1-sha1
+%%% diffie-hellman-group14-sha1
+%%%
+handle_kexdh_init(#ssh_msg_kexdh_init{e = E},
+ Ssh0 = #ssh{algorithms = #alg{kex=Kex}}) ->
+ %% server
+ {G, P} = dh_group(Kex),
if
1=<E, E=<(P-1) ->
{Private, Public} = dh_gen_key(G, P, 1024),
- K = ssh_math:ipow(E, Private, P),
+ K = dh_compute_key(G, P, E, Private),
Key = get_host_key(Ssh0),
H = kex_h(Ssh0, Key, E, Public, K),
H_SIG = sign_host_key(Ssh0, Key, H),
@@ -299,27 +346,173 @@ handle_kexdh_init(#ssh_msg_kexdh_init{e = E}, Ssh0) ->
f = Public,
h_sig = H_SIG
}, Ssh0),
-
{ok, SshPacket, Ssh1#ssh{keyex_key = {{Private, Public}, {G, P}},
shared_secret = K,
exchanged_hash = H,
session_id = sid(Ssh1, H)}};
+
true ->
- Error = {error,bad_e_from_peer},
- Disconnect = #ssh_msg_disconnect{
- code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
- description = "Key exchange failed, 'f' out of bounds",
- language = "en"},
- throw({Error, Disconnect})
+ throw({{error,bad_e_from_peer},
+ #ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Key exchange failed, 'e' out of bounds",
+ language = ""}
+ })
end.
+handle_kexdh_reply(#ssh_msg_kexdh_reply{public_host_key = HostKey,
+ f = F,
+ h_sig = H_SIG},
+ #ssh{keyex_key = {{Private, Public}, {G, P}}} = Ssh0) ->
+ %% client
+ if
+ 1=<F, F=<(P-1)->
+ K = dh_compute_key(G, P, F, Private),
+ H = kex_h(Ssh0, HostKey, Public, F, K),
+
+ case verify_host_key(Ssh0, HostKey, H, H_SIG) of
+ ok ->
+ {SshPacket, Ssh} = ssh_packet(#ssh_msg_newkeys{}, Ssh0),
+ {ok, SshPacket, Ssh#ssh{shared_secret = K,
+ exchanged_hash = H,
+ session_id = sid(Ssh, H)}};
+ Error ->
+ throw({Error,
+ #ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Key exchange failed",
+ language = "en"}
+ })
+ end;
+
+ true ->
+ throw({{error,bad_f_from_peer},
+ #ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Key exchange failed, 'f' out of bounds",
+ language = ""}
+ })
+ end.
+
+
+%%%----------------------------------------------------------------
+%%%
+%%% diffie-hellman-group-exchange-sha1
+%%%
+handle_kex_dh_gex_request(#ssh_msg_kex_dh_gex_request{min = Min,
+ n = NBits,
+ max = Max},
+ Ssh0=#ssh{opts=Opts}) when Min=<NBits, NBits=<Max ->
+ %% server
+ {G, P} = dh_gex_group(Min, NBits, Max, proplists:get_value(dh_gex_groups,Opts)),
+ {Private, Public} = dh_gen_key(G, P, 1024),
+ {SshPacket, Ssh} =
+ ssh_packet(#ssh_msg_kex_dh_gex_group{p = P, g = G}, Ssh0),
+ {ok, SshPacket,
+ Ssh#ssh{keyex_key = {{Private, Public}, {G, P}},
+ keyex_info = {Min, Max, NBits}
+ }};
+handle_kex_dh_gex_request(_, _) ->
+ throw({{error,bad_ssh_msg_kex_dh_gex_request},
+ #ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Key exchange failed, bad values in ssh_msg_kex_dh_gex_request",
+ language = ""}
+ }).
+
handle_kex_dh_gex_group(#ssh_msg_kex_dh_gex_group{p = P, g = G}, Ssh0) ->
- {Private, Public} = dh_gen_key(G,P,1024),
+ %% client
+ {Private, Public} = dh_gen_key(G, P, 1024),
{SshPacket, Ssh1} =
- ssh_packet(#ssh_msg_kex_dh_gex_init{e = Public}, Ssh0),
+ ssh_packet(#ssh_msg_kex_dh_gex_init{e = Public}, Ssh0), % Pub = G^Priv mod P (def)
+
{ok, SshPacket,
Ssh1#ssh{keyex_key = {{Private, Public}, {G, P}}}}.
+handle_kex_dh_gex_init(#ssh_msg_kex_dh_gex_init{e = E},
+ #ssh{keyex_key = {{Private, Public}, {G, P}},
+ keyex_info = {Min, Max, NBits}} =
+ Ssh0) ->
+ %% server
+ if
+ 1=<E, E=<(P-1) ->
+ K = dh_compute_key(G, P, E, Private),
+ if
+ 1<K, K<(P-1) ->
+ HostKey = get_host_key(Ssh0),
+ H = kex_h(Ssh0, HostKey, Min, NBits, Max, P, G, E, Public, K),
+ H_SIG = sign_host_key(Ssh0, HostKey, H),
+ {SshPacket, Ssh} =
+ ssh_packet(#ssh_msg_kex_dh_gex_reply{public_host_key = HostKey,
+ f = Public,
+ h_sig = H_SIG}, Ssh0),
+ {ok, SshPacket, Ssh#ssh{shared_secret = K,
+ exchanged_hash = H,
+ session_id = sid(Ssh, H)
+ }};
+ true ->
+ throw({{error,bad_K},
+ #ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Key exchange failed, 'K' out of bounds",
+ language = ""}
+ })
+ end;
+ true ->
+ throw({{error,bad_e_from_peer},
+ #ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Key exchange failed, 'e' out of bounds",
+ language = ""}
+ })
+ end.
+
+handle_kex_dh_gex_reply(#ssh_msg_kex_dh_gex_reply{public_host_key = HostKey,
+ f = F,
+ h_sig = H_SIG},
+ #ssh{keyex_key = {{Private, Public}, {G, P}},
+ keyex_info = {Min, Max, NBits}} =
+ Ssh0) ->
+ %% client
+ if
+ 1=<F, F=<(P-1)->
+ K = dh_compute_key(G, P, F, Private),
+ if
+ 1<K, K<(P-1) ->
+ H = kex_h(Ssh0, HostKey, Min, NBits, Max, P, G, Public, F, K),
+
+ case verify_host_key(Ssh0, HostKey, H, H_SIG) of
+ ok ->
+ {SshPacket, Ssh} = ssh_packet(#ssh_msg_newkeys{}, Ssh0),
+ {ok, SshPacket, Ssh#ssh{shared_secret = K,
+ exchanged_hash = H,
+ session_id = sid(Ssh, H)}};
+ _Error ->
+ throw(#ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Key exchange failed",
+ language = ""}
+ )
+ end;
+
+ true ->
+ throw({{error,bad_K},
+ #ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Key exchange failed, 'K' out of bounds",
+ language = ""}
+ })
+ end;
+ true ->
+ throw({{error,bad_f_from_peer},
+ #ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
+ description = "Key exchange failed, 'f' out of bounds",
+ language = ""}
+ })
+ end.
+
+%%%----------------------------------------------------------------
handle_new_keys(#ssh_msg_newkeys{}, Ssh0) ->
try install_alg(Ssh0) of
#ssh{} = Ssh ->
@@ -331,69 +524,6 @@ handle_new_keys(#ssh_msg_newkeys{}, Ssh0) ->
language = "en"})
end.
-
-%% %% Select algorithms
-handle_kexdh_reply(#ssh_msg_kexdh_reply{public_host_key = HostKey, f = F,
- h_sig = H_SIG},
- #ssh{keyex_key = {{Private, Public}, {_G, P}}} = Ssh0) when 1=<F, F=<(P-1)->
- K = ssh_math:ipow(F, Private, P),
- H = kex_h(Ssh0, HostKey, Public, F, K),
-
- case verify_host_key(Ssh0, HostKey, H, H_SIG) of
- ok ->
- {SshPacket, Ssh} = ssh_packet(#ssh_msg_newkeys{}, Ssh0),
- {ok, SshPacket, Ssh#ssh{shared_secret = K,
- exchanged_hash = H,
- session_id = sid(Ssh, H)}};
- Error ->
- Disconnect = #ssh_msg_disconnect{
- code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
- description = "Key exchange failed",
- language = "en"},
- throw({Error, Disconnect})
- end;
-handle_kexdh_reply(#ssh_msg_kexdh_reply{}, _SSH) ->
- Error = {error,bad_f_from_peer},
- Disconnect = #ssh_msg_disconnect{
- code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
- description = "Key exchange failed, 'f' out of bounds",
- language = "en"},
- throw({Error, Disconnect}).
-
-
-handle_kex_dh_gex_request(#ssh_msg_kex_dh_gex_request{min = _Min,
- n = _NBits,
- max = _Max}, Ssh0) ->
- {G,P} = dh_group1(), %% TODO real imp this seems to be a hack?!
- {Private, Public} = dh_gen_key(G, P, 1024),
- {SshPacket, Ssh} =
- ssh_packet(#ssh_msg_kex_dh_gex_group{p = P, g = G}, Ssh0),
- {ok, SshPacket,
- Ssh#ssh{keyex_key = {{Private, Public}, {G, P}}}}.
-
-handle_kex_dh_gex_reply(#ssh_msg_kex_dh_gex_reply{public_host_key = HostKey,
- f = F,
- h_sig = H_SIG},
- #ssh{keyex_key = {{Private, Public}, {G, P}},
- keyex_info = {Min, Max, NBits}} =
- Ssh0) ->
- K = ssh_math:ipow(F, Private, P),
- H = kex_h(Ssh0, HostKey, Min, NBits, Max, P, G, Public, F, K),
-
- case verify_host_key(Ssh0, HostKey, H, H_SIG) of
- ok ->
- {SshPacket, Ssh} = ssh_packet(#ssh_msg_newkeys{}, Ssh0),
- {ok, SshPacket, Ssh#ssh{shared_secret = K,
- exchanged_hash = H,
- session_id = sid(Ssh, H)}};
- _Error ->
- Disconnect = #ssh_msg_disconnect{
- code = ?SSH_DISCONNECT_KEY_EXCHANGE_FAILED,
- description = "Key exchange failed",
- language = "en"},
- throw(Disconnect)
- end.
-
%% select session id
sid(#ssh{session_id = undefined}, H) ->
H;
@@ -496,7 +626,6 @@ select_algorithm(Role, Client, Server) ->
decompress = Decompression,
c_lng = C_Lng,
s_lng = S_Lng},
-%%ct:pal("~p~n Client=~p~n Server=~p~n Alg=~p~n",[Role,Client,Server,Alg]),
{ok, Alg}.
select_encrypt_decrypt(client, Client, Server) ->
@@ -691,6 +820,7 @@ verify(PlainText, Hash, Sig, Key) ->
%% key exchange
%%
%% diffie-hellman-group1-sha1 REQUIRED
+%% diffie-hellman-group14-sha1 REQUIRED
%%
%%
@@ -986,7 +1116,7 @@ recv_mac_init(SSH) ->
recv_mac_final(SSH) ->
{ok, SSH#ssh { recv_mac = none, recv_mac_key = undefined }}.
-mac(none, _ , _, _) ->
+mac(none, _ , _, _) ->
<<>>;
mac('hmac-sha1', Key, SeqNum, Data) ->
crypto:hmac(sha, Key, [<<?UINT32(SeqNum)>>, Data]);
@@ -1005,8 +1135,12 @@ hash(SSH, Char, Bits) ->
case SSH#ssh.kex of
'diffie-hellman-group1-sha1' ->
fun(Data) -> crypto:hash(sha, Data) end;
+ 'diffie-hellman-group14-sha1' ->
+ fun(Data) -> crypto:hash(sha, Data) end;
'diffie-hellman-group-exchange-sha1' ->
fun(Data) -> crypto:hash(sha, Data) end;
+ 'diffie-hellman-group-exchange-sha256' ->
+ fun(Data) -> crypto:hash(sha256, Data) end;
_ ->
exit({bad_algorithm,SSH#ssh.kex})
end,
@@ -1056,8 +1190,11 @@ kex_h(SSH, Key, Min, NBits, Max, Prime, Gen, E, F, K) ->
ssh_message:encode_host_key(Key), Min, NBits, Max,
Prime, Gen, E,F,K], Ts)
end,
- crypto:hash(sha,L).
+ crypto:hash(sha((SSH#ssh.algorithms)#alg.kex), L).
+sha('diffie-hellman-group-exchange-sha1') -> sha;
+sha('diffie-hellman-group-exchange-sha256') -> sha256.
+
mac_key_size('hmac-sha1') -> 20*8;
mac_key_size('hmac-sha1-96') -> 20*8;
mac_key_size('hmac-md5') -> 16*8;
@@ -1081,13 +1218,63 @@ peer_name({Host, _}) ->
%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-dh_group1() ->
- {2, 16#FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF}.
+dh_group('diffie-hellman-group1-sha1') -> ?dh_group1;
+dh_group('diffie-hellman-group14-sha1') -> ?dh_group14.
+
+dh_gex_default_groups() ->
+ [{1024, ?dh_group1 },
+ {2048, ?dh_group14},
+ {3072, ?dh_group15},
+ {4096, ?dh_group16}].
+
+
+dh_gex_group(Min, N, Max, undefined) ->
+ dh_gex_group(Min, N, Max, dh_gex_default_groups());
+dh_gex_group(Min, N, Max, Groups) ->
+ %% First try to find an exact match. If not an exact match, select the largest possible.
+ {_,Group} =
+ lists:foldl(
+ fun(_, {I,G}) when I==N ->
+ %% If we have an exact match already: use that one
+ {I,G};
+ ({I,G}, _) when I==N ->
+ %% If we now found an exact match: use that very one
+ {I,G};
+ ({I,G}, {Imax,_Gmax}) when Min=<I,I=<Max, % a) {I,G} fullfills the requirements
+ I>Imax -> % b) {I,G} is larger than current max
+ %% A group within the limits and better than the one we have
+ {I,G};
+ (_, IGmax) ->
+ %% Keep the one we have
+ IGmax
+ end, {-1,undefined}, Groups),
+
+ case Group of
+ undefined ->
+ throw(#ssh_msg_disconnect{
+ code = ?SSH_DISCONNECT_PROTOCOL_ERROR,
+ description = "No possible diffie-hellman-group-exchange group found",
+ language = ""});
+ _ ->
+ Group
+ end.
+
dh_gen_key(G, P, _) ->
{Public, Private} = crypto:generate_key(dh, [P, G]),
{crypto:bytes_to_integer(Private), crypto:bytes_to_integer(Public)}.
+dh_compute_key(G, P, OthersPublic, MyPrivate) ->
+ crypto:bytes_to_integer(
+ crypto:compute_key(dh, OthersPublic, MyPrivate, [P,G])
+ ).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%
+%% Other utils
+%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
trim_tail(Str) ->
lists:reverse(trim_head(lists:reverse(Str))).
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-06 01:03:07 +0000