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-rw-r--r--lib/ssh/src/ssh_transport.erl141
1 files changed, 97 insertions, 44 deletions
diff --git a/lib/ssh/src/ssh_transport.erl b/lib/ssh/src/ssh_transport.erl
index d6414bab6c..ea9bca2390 100644
--- a/lib/ssh/src/ssh_transport.erl
+++ b/lib/ssh/src/ssh_transport.erl
@@ -31,6 +31,8 @@
-export([versions/2, hello_version_msg/1]).
-export([next_seqnum/1, decrypt_first_block/2, decrypt_blocks/3,
+ supported_algorithms/0, supported_algorithms/1,
+ default_algorithms/0, default_algorithms/1,
is_valid_mac/3,
handle_hello_version/1,
key_exchange_init_msg/1,
@@ -42,6 +44,68 @@
unpack/3, decompress/2, ssh_packet/2, pack/2, msg_data/1,
sign/3, verify/4]).
+%%%----------------------------------------------------------------------------
+%%%
+%%% There is a difference between supported and default algorithms. The
+%%% SUPPORTED algorithms can be handled (maybe untested...). The DEFAULT ones
+%%% are announced in ssh_msg_kexinit and in ssh:default_algorithms/0 to the
+%%% user.
+%%%
+%%% A supported algorithm can be requested in the option 'preferred_algorithms',
+%%% but may give unexpected results because of being promoted to default.
+%%%
+%%% This makes it possible to add experimental algorithms (in supported_algorithms)
+%%% and test them without letting the default users know about them.
+%%%
+
+default_algorithms() -> [{K,default_algorithms(K)} || K <- algo_classes()].
+
+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(Alg) ->
+ supported_algorithms(Alg).
+
+
+supported_algorithms() -> [{K,supported_algorithms(K)} || K <- algo_classes()].
+
+supported_algorithms(kex) ->
+ ['diffie-hellman-group1-sha1'];
+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);
+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);
+supported_algorithms(compression) ->
+ same(['none','zlib','[email protected]']).
+
+
+supported_algorithms(Key, [{client2server,BL1},{server2client,BL2}]) ->
+ [{client2server,As1},{server2client,As2}] = supported_algorithms(Key),
+ [{client2server,As1--BL1},{server2client,As2--BL2}];
+supported_algorithms(Key, BlackList) ->
+ supported_algorithms(Key) -- BlackList.
+
+
+
+
+same(Algs) -> [{client2server,Algs}, {server2client,Algs}].
+
+
+%%%----------------------------------------------------------------------------
versions(client, Options)->
Vsn = proplists:get_value(vsn, Options, ?DEFAULT_CLIENT_VERSION),
{Vsn, format_version(Vsn, software_version(Options))};
@@ -128,62 +192,45 @@ key_exchange_init_msg(Ssh0) ->
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
- openssh_zlib -> ["[email protected]", "none"];
- zlib -> ["zlib", "none"];
- none -> ["none", "zlib"]
- end,
- kexinit_messsage(Role, Random, Compression, HostKeyAlgs).
+ PrefAlgs =
+ case proplists:get_value(preferred_algorithms,Opts) of
+ undefined ->
+ default_algorithms();
+ Algs0 ->
+ Algs0
+ end,
+ kexinit_message(Role, Random, PrefAlgs, HostKeyAlgs).
key_init(client, Ssh, Value) ->
Ssh#ssh{c_keyinit = Value};
key_init(server, Ssh, Value) ->
Ssh#ssh{s_keyinit = Value}.
-available_ssh_algos() ->
- Supports = crypto:supports(),
- CipherAlgos = [{aes_ctr, "aes128-ctr"}, {aes_cbc128, "aes128-cbc"}, {des3_cbc, "3des-cbc"}],
- Ciphers = [SshAlgo ||
- {CryptoAlgo, SshAlgo} <- CipherAlgos,
- lists:member(CryptoAlgo, proplists:get_value(ciphers, Supports, []))],
- HashAlgos = [{sha256, "hmac-sha2-256"}, {sha, "hmac-sha1"}],
- Hashs = [SshAlgo ||
- {CryptoAlgo, SshAlgo} <- HashAlgos,
- lists:member(CryptoAlgo, proplists:get_value(hashs, Supports, []))],
- {Ciphers, Hashs}.
-
-kexinit_messsage(client, Random, Compression, HostKeyAlgs) ->
- {CipherAlgs, HashAlgs} = available_ssh_algos(),
- #ssh_msg_kexinit{
- cookie = Random,
- kex_algorithms = ["diffie-hellman-group1-sha1"],
- server_host_key_algorithms = HostKeyAlgs,
- encryption_algorithms_client_to_server = CipherAlgs,
- encryption_algorithms_server_to_client = CipherAlgs,
- mac_algorithms_client_to_server = HashAlgs,
- mac_algorithms_server_to_client = HashAlgs,
- compression_algorithms_client_to_server = Compression,
- compression_algorithms_server_to_client = Compression,
- languages_client_to_server = [],
- languages_server_to_client = []
- };
-kexinit_messsage(server, Random, Compression, HostKeyAlgs) ->
- {CipherAlgs, HashAlgs} = available_ssh_algos(),
+kexinit_message(_Role, Random, Algs, HostKeyAlgs) ->
#ssh_msg_kexinit{
cookie = Random,
- kex_algorithms = ["diffie-hellman-group1-sha1"],
+ kex_algorithms = to_strings( get_algs(kex,Algs) ),
server_host_key_algorithms = HostKeyAlgs,
- encryption_algorithms_client_to_server = CipherAlgs,
- encryption_algorithms_server_to_client = CipherAlgs,
- mac_algorithms_client_to_server = HashAlgs,
- mac_algorithms_server_to_client = HashAlgs,
- compression_algorithms_client_to_server = Compression,
- compression_algorithms_server_to_client = Compression,
+ encryption_algorithms_client_to_server = c2s(cipher,Algs),
+ encryption_algorithms_server_to_client = s2c(cipher,Algs),
+ mac_algorithms_client_to_server = c2s(mac,Algs),
+ mac_algorithms_server_to_client = s2c(mac,Algs),
+ compression_algorithms_client_to_server = c2s(compression,Algs),
+ compression_algorithms_server_to_client = s2c(compression,Algs),
languages_client_to_server = [],
languages_server_to_client = []
}.
+c2s(Key, Algs) -> x2y(client2server, Key, Algs).
+s2c(Key, Algs) -> x2y(server2client, Key, Algs).
+
+x2y(DirectionKey, Key, Algs) -> to_strings(proplists:get_value(DirectionKey, get_algs(Key,Algs))).
+
+get_algs(Key, Algs) -> proplists:get_value(Key, Algs, default_algorithms(Key)).
+
+to_strings(L) -> lists:map(fun erlang:atom_to_list/1, L).
+
new_keys_message(Ssh0) ->
{SshPacket, Ssh} =
ssh_packet(#ssh_msg_newkeys{}, Ssh0),
@@ -448,6 +495,7 @@ 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) ->
@@ -537,10 +585,15 @@ alg_final(SSH0) ->
{ok,SSH6} = decompress_final(SSH5),
SSH6.
-select_all(CL, SL) ->
+select_all(CL, SL) when length(CL) + length(SL) < 50 ->
A = CL -- SL, %% algortihms only used by client
%% algorithms used by client and server (client pref)
- lists:map(fun(ALG) -> list_to_atom(ALG) end, (CL -- A)).
+ lists:map(fun(ALG) -> list_to_atom(ALG) end, (CL -- A));
+select_all(_CL, _SL) ->
+ throw(#ssh_msg_disconnect{code = ?SSH_DISCONNECT_PROTOCOL_ERROR,
+ description = "Too many algorithms",
+ language = "en"}).
+
select([], []) ->
none;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-01 04:08:34 +0000