diff options
Diffstat (limited to 'lib/ssh/src/ssh_transport.erl')
| -rw-r--r-- | lib/ssh/src/ssh_transport.erl | 131 |
1 files changed, 89 insertions, 42 deletions
diff --git a/lib/ssh/src/ssh_transport.erl b/lib/ssh/src/ssh_transport.erl index d6414bab6c..95840c94ad 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), |