The R13B03 release.OTP_R13B03

1 files changed, 665 insertions, 0 deletions

diff --git a/lib/crypto/src/crypto.erl b/lib/crypto/src/crypto.erl
new file mode 100644
index 0000000000..5189677dd0
--- /dev/null
+++ b/lib/crypto/src/crypto.erl
@@ -0,0 +1,665 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 1999-2009. 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
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%% 
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%% 
+%% %CopyrightEnd%
+%%
+
+%% Purpose : Main Crypto API module.
+
+-module(crypto).
+
+-export([start/0, stop/0, info/0, info_lib/0]).
+-export([md4/1, md4_init/0, md4_update/2, md4_final/1]).
+-export([md5/1, md5_init/0, md5_update/2, md5_final/1]).
+-export([sha/1, sha_init/0, sha_update/2, sha_final/1]).
+%-export([sha256/1, sha256_init/0, sha256_update/2, sha256_final/1]).
+%-export([sha512/1, sha512_init/0, sha512_update/2, sha512_final/1]).
+-export([md5_mac/2, md5_mac_96/2, sha_mac/2, sha_mac_96/2]).
+-export([des_cbc_encrypt/3, des_cbc_decrypt/3, des_cbc_ivec/1]).
+-export([des3_cbc_encrypt/5, des3_cbc_decrypt/5]).
+-export([blowfish_cfb64_encrypt/3,blowfish_cfb64_decrypt/3]).
+-export([des_ede3_cbc_encrypt/5, des_ede3_cbc_decrypt/5]).
+-export([aes_cfb_128_encrypt/3, aes_cfb_128_decrypt/3]).
+-export([exor/2]).
+-export([rc4_encrypt/2, rc4_set_key/1, rc4_encrypt_with_state/2]).
+-export([rc2_40_cbc_encrypt/3, rc2_40_cbc_decrypt/3]).
+-export([dss_verify/3, rsa_verify/3, rsa_verify/4]).
+-export([dss_sign/2, rsa_sign/2, rsa_sign/3]).
+-export([rsa_public_encrypt/3, rsa_private_decrypt/3]).
+-export([rsa_private_encrypt/3, rsa_public_decrypt/3]).
+-export([dh_generate_key/1, dh_generate_key/2, dh_compute_key/3]).
+-export([rand_bytes/1, rand_bytes/3, rand_uniform/2]).
+-export([mod_exp/3, mpint/1, erlint/1]).
+%% -export([idea_cbc_encrypt/3, idea_cbc_decrypt/3]).
+-export([aes_cbc_128_encrypt/3, aes_cbc_128_decrypt/3]).
+-export([aes_cbc_256_encrypt/3, aes_cbc_256_decrypt/3]).
+-export([aes_cbc_ivec/1]).
+
+-export([dh_generate_parameters/2, dh_check/1]). %% Testing see below
+
+-define(INFO,		 0).
+-define(MD5,		 1).
+-define(MD5_INIT,	 2).
+-define(MD5_UPDATE,	 3).
+-define(MD5_FINAL,	 4).
+-define(SHA,		 5).
+-define(SHA_INIT,	 6).
+-define(SHA_UPDATE,	 7).
+-define(SHA_FINAL,	 8).
+-define(MD5_MAC,	 9).
+-define(MD5_MAC_96,	 10).
+-define(SHA_MAC,	 11).
+-define(SHA_MAC_96,	 12).
+-define(DES_CBC_ENCRYPT, 13).
+-define(DES_CBC_DECRYPT, 14).
+-define(DES_EDE3_CBC_ENCRYPT, 15).
+-define(DES_EDE3_CBC_DECRYPT, 16).
+-define(AES_CFB_128_ENCRYPT, 17).
+-define(AES_CFB_128_DECRYPT, 18).
+-define(RAND_BYTES,	 19).
+-define(RAND_UNIFORM,    20).
+-define(MOD_EXP,	 21).
+-define(DSS_VERIFY,	 22).
+-define(RSA_VERIFY_SHA,	 23).
+%-define(RSA_VERIFY_MD5,	 35).
+-define(AES_CBC_128_ENCRYPT, 24).
+-define(AES_CBC_128_DECRYPT, 25).
+-define(XOR,		 26).
+-define(RC4_ENCRYPT,     27).
+-define(RC4_SET_KEY, 28).
+-define(RC4_ENCRYPT_WITH_STATE, 29).
+-define(RC2_40_CBC_ENCRYPT, 30).
+-define(RC2_40_CBC_DECRYPT, 31).
+-define(AES_CBC_256_ENCRYPT, 32).
+-define(AES_CBC_256_DECRYPT, 33).
+-define(INFO_LIB,34).
+%-define(RSA_VERIFY_SHA,	 23).
+-define(RSA_VERIFY_MD5,	 35).
+-define(RSA_SIGN_SHA,    36).
+-define(RSA_SIGN_MD5,    37).
+-define(DSS_SIGN,        38).
+-define(RSA_PUBLIC_ENCRYPT,  39).
+-define(RSA_PRIVATE_DECRYPT, 40).
+-define(RSA_PRIVATE_ENCRYPT, 41).
+-define(RSA_PUBLIC_DECRYPT,  42).
+-define(DH_GENERATE_PARAMS,  43).
+-define(DH_CHECK,            44).
+-define(DH_GENERATE_KEY,     45).
+-define(DH_COMPUTE_KEY,      46).
+-define(MD4,		 47).
+-define(MD4_INIT,	 48).
+-define(MD4_UPDATE,	 49).
+-define(MD4_FINAL,	 50).
+
+%% -define(SHA256,		 51).
+%% -define(SHA256_INIT,	 52).
+%% -define(SHA256_UPDATE,	 53).
+%% -define(SHA256_FINAL,	 54).
+%% -define(SHA512,		 55).
+%% -define(SHA512_INIT,	 56).
+%% -define(SHA512_UPDATE,	 57).
+%% -define(SHA512_FINAL,	 58).
+
+-define(BF_CFB64_ENCRYPT, 59).
+-define(BF_CFB64_DECRYPT, 60).
+
+%% -define(IDEA_CBC_ENCRYPT, 34).
+%% -define(IDEA_CBC_DECRYPT, 35).
+
+-define(FUNC_LIST, [md4, md4_init, md4_update, md4_final,
+		    md5, md5_init, md5_update, md5_final,
+		    sha, sha_init, sha_update, sha_final,
+%% 		    sha256, sha256_init, sha256_update, sha256_final,
+%% 		    sha512, sha512_init, sha512_update, sha512_final,
+		    md5_mac,  md5_mac_96,
+		    sha_mac,  sha_mac_96,
+		    des_cbc_encrypt, des_cbc_decrypt,
+		    des_ede3_cbc_encrypt, des_ede3_cbc_decrypt,
+		    aes_cfb_128_encrypt, aes_cfb_128_decrypt,
+		    rand_bytes,
+		    rand_uniform,
+		    mod_exp,
+		    dss_verify,dss_sign,
+		    rsa_verify,rsa_sign,
+		    rsa_public_encrypt,rsa_private_decrypt, 
+		    rsa_private_encrypt,rsa_public_decrypt, 
+		    dh_generate_key, dh_compute_key,
+		    aes_cbc_128_encrypt, aes_cbc_128_decrypt,
+		    exor,
+		    rc4_encrypt, rc4_set_key, rc4_encrypt_with_state,
+		    rc2_40_cbc_encrypt, rc2_40_cbc_decrypt,
+		    %% idea_cbc_encrypt, idea_cbc_decrypt,
+		    aes_cbc_256_encrypt, aes_cbc_256_decrypt,
+		    info_lib]).
+
+start() ->
+    application:start(crypto).
+
+stop() ->
+    application:stop(crypto).
+
+info() ->
+    lists:map(fun(I) -> 
+		      lists:nth(I, ?FUNC_LIST) 
+	      end, binary_to_list(control(?INFO, []))).
+
+info_lib() ->
+    <<_DrvVer:8, NameSize:8, Name:NameSize/binary,
+      VerNum:32, VerStr/binary>> = control(?INFO_LIB,[]),
+    [{Name,VerNum,VerStr}].
+
+%% Below Key and Data are binaries or IO-lists. IVec is a binary.
+%% Output is always a binary. Context is a binary.
+
+%%
+%%  MESSAGE DIGESTS
+%%
+
+%%
+%%  MD5
+%%
+md5(Data) ->
+    control(?MD5, Data).
+
+md5_init() ->
+    control(?MD5_INIT, []).
+
+md5_update(Context, Data) ->
+    control(?MD5_UPDATE, [Context, Data]).
+
+md5_final(Context) ->
+    control(?MD5_FINAL, Context).
+
+%%
+%%  MD4
+%%
+md4(Data) ->
+    control(?MD4, Data).
+
+md4_init() ->
+    control(?MD4_INIT, []).
+
+md4_update(Context, Data) ->
+    control(?MD4_UPDATE, [Context, Data]).
+
+md4_final(Context) ->
+    control(?MD4_FINAL, Context).
+
+%%
+%% SHA
+%%
+sha(Data) ->
+    control(?SHA, Data).
+
+sha_init() ->
+    control(?SHA_INIT, []).
+
+sha_update(Context, Data) ->
+    control(?SHA_UPDATE, [Context, Data]).
+
+sha_final(Context) ->
+    control(?SHA_FINAL, Context).
+
+%% sha256 and sha512 requires openssl-0.9.8 removed for now
+
+%% sha256(Data) ->
+%%     control(?SHA256, Data).
+
+%% sha256_init() ->
+%%     control(?SHA256_INIT, []).
+
+%% sha256_update(Context, Data) ->
+%%     control(?SHA256_UPDATE, [Context, Data]).
+
+%% sha256_final(Context) ->
+%%         control(?SHA256_FINAL, Context).
+
+%% sha512(Data) ->
+%%     control(?SHA512, Data).
+
+%% sha512_init() ->
+%%     control(?SHA512_INIT, []).
+
+%% sha512_update(Context, Data) ->
+%%     control(?SHA512_UPDATE, [Context, Data]).
+
+%% sha512_final(Context) ->
+%%     control(?SHA512_FINAL, Context).
+
+%%
+%%  MESSAGE AUTHENTICATION CODES
+%%
+
+%%
+%%  MD5_MAC
+%%
+md5_mac(Key, Data) ->
+    control_bin(?MD5_MAC, Key, Data).
+
+md5_mac_96(Key, Data) ->
+    control_bin(?MD5_MAC_96, Key, Data).
+
+%%
+%%  SHA_MAC
+%%
+sha_mac(Key, Data) ->
+    control_bin(?SHA_MAC, Key, Data).
+
+sha_mac_96(Key, Data) ->
+    control_bin(?SHA_MAC_96, Key, Data).
+
+%%
+%% CRYPTO FUNCTIONS
+%%
+
+%%
+%% DES - in cipher block chaining mode (CBC)
+%%
+des_cbc_encrypt(Key, IVec, Data) ->
+    control(?DES_CBC_ENCRYPT, [Key, IVec, Data]).
+
+des_cbc_decrypt(Key, IVec, Data) ->
+    control(?DES_CBC_DECRYPT, [Key, IVec, Data]).
+
+%%
+%% dec_cbc_ivec(Data) -> binary()
+%%
+%% Returns the IVec to be used in the next iteration of 
+%% des_cbc_[encrypt|decrypt].
+%%
+des_cbc_ivec(Data) when is_binary(Data) -> 
+    {_, IVec} = split_binary(Data, size(Data) - 8),
+    IVec;
+des_cbc_ivec(Data) when is_list(Data) ->
+    des_cbc_ivec(list_to_binary(Data)).
+
+%%
+%% DES3 - in cipher block chaining mode (CBC)
+%%
+des3_cbc_encrypt(Key1, Key2, Key3, IVec, Data) ->
+    des_ede3_cbc_encrypt(Key1, Key2, Key3, IVec, Data).
+des_ede3_cbc_encrypt(Key1, Key2, Key3, IVec, Data) ->
+    %%io:format("des_ede3_cbc_encrypt: size(Data)=~p\n", [size(list_to_binary([Data]))]),
+    control(?DES_EDE3_CBC_ENCRYPT, [Key1, Key2, Key3, IVec, Data]).
+
+des3_cbc_decrypt(Key1, Key2, Key3, IVec, Data) ->
+    des_ede3_cbc_decrypt(Key1, Key2, Key3, IVec, Data).
+des_ede3_cbc_decrypt(Key1, Key2, Key3, IVec, Data) ->
+    control(?DES_EDE3_CBC_DECRYPT, [Key1, Key2, Key3, IVec, Data]).
+
+%%
+%% Blowfish
+%%
+blowfish_cfb64_encrypt(Key, IVec, Data) when byte_size(IVec) =:= 8 ->
+    control_bin(?BF_CFB64_ENCRYPT, Key, list_to_binary([IVec, Data])).
+
+blowfish_cfb64_decrypt(Key, IVec, Data) when byte_size(IVec) =:= 8 ->
+    control_bin(?BF_CFB64_DECRYPT, Key, list_to_binary([IVec, Data])).
+
+%%
+%% AES in cipher feedback mode (CFB)
+%%
+aes_cfb_128_encrypt(Key, IVec, Data) ->
+    control(?AES_CFB_128_ENCRYPT, [Key, IVec, Data]).
+
+aes_cfb_128_decrypt(Key, IVec, Data) ->
+    control(?AES_CFB_128_DECRYPT, [Key, IVec, Data]).    
+
+
+%% %%
+%% %% IDEA - in cipher block chaining mode (CBC)
+%% %%
+%% idea_cbc_encrypt(Key, IVec, Data) ->
+%%     control(?IDEA_CBC_ENCRYPT, [Key, IVec, Data]).
+
+%% idea_cbc_decrypt(Key, IVec, Data) ->
+%%     control(?IDEA_CBC_DECRYPT, [Key, IVec, Data]).
+
+
+%% 
+%% RAND - pseudo random numbers using RN_ functions in crypto lib
+%%
+
+rand_bytes(Bytes) ->
+    rand_bytes(Bytes, 0, 0).
+rand_bytes(Bytes, Topmask, Bottommask) ->
+    control(?RAND_BYTES,[<<Bytes:32/integer,
+			  Topmask:8/integer,
+			  Bottommask:8/integer>>]).
+
+rand_uniform(From,To) when is_binary(From), is_binary(To) ->
+    case control(?RAND_UNIFORM,[From,To]) of
+	<<Len:32/integer, MSB, Rest/binary>> when MSB > 127 ->
+	    <<(Len + 1):32/integer, 0, MSB, Rest/binary>>;
+	Whatever ->
+	    Whatever
+    end;
+rand_uniform(From,To) when is_integer(From),is_integer(To) ->
+    BinFrom = mpint(From),
+    BinTo = mpint(To),
+    case rand_uniform(BinFrom, BinTo) of
+        Result when is_binary(Result) ->
+            erlint(Result);
+        Other ->
+            Other
+    end.
+
+%%
+%% mod_exp - utility for rsa generation
+%%
+mod_exp(Base, Exponent, Modulo)
+  when is_integer(Base), is_integer(Exponent), is_integer(Modulo) ->
+    erlint(mod_exp(mpint(Base), mpint(Exponent), mpint(Modulo)));
+
+mod_exp(Base, Exponent, Modulo) ->
+    case control(?MOD_EXP,[Base,Exponent,Modulo]) of
+	<<Len:32/integer, MSB, Rest/binary>> when MSB > 127 ->
+	    <<(Len + 1):32/integer, 0, MSB, Rest/binary>>;
+	Whatever ->
+	    Whatever
+    end.
+
+%%
+%% DSS, RSA - verify
+%%
+
+%% Key = [P,Q,G,Y]   P,Q,G=DSSParams  Y=PublicKey
+dss_verify(Data,Signature,Key) ->
+    control(?DSS_VERIFY, [Data,Signature,Key]) == <<1>>.
+
+% Key = [E,N]  E=PublicExponent N=PublicModulus
+rsa_verify(Data,Signature,Key) ->
+    rsa_verify(sha, Data,Signature,Key).
+rsa_verify(Type,Data,Signature,Key) ->
+    control(rsa_verify_digest_type(Type), [Data,Signature,Key]) == <<1>>.
+
+rsa_verify_digest_type(md5) -> ?RSA_VERIFY_MD5;
+rsa_verify_digest_type(sha) -> ?RSA_VERIFY_SHA;
+rsa_verify_digest_type(Bad) -> erlang:error(badarg, [Bad]).
+
+%%
+%% DSS, RSA - sign
+%%
+%% Key = [P,Q,G,X]   P,Q,G=DSSParams  X=PrivateKey
+dss_sign(Data, Key) ->
+    <<Ret:8, Signature/binary>> = control(?DSS_SIGN, [Data,Key]),
+    case Ret of
+	1 -> Signature;
+	0 -> erlang:error(badkey, [Data, Key])
+    end.
+
+%% Key = [E,N,D]  E=PublicExponent N=PublicModulus  D=PrivateExponent
+rsa_sign(Data,Key) ->
+    rsa_sign(sha, Data, Key).
+rsa_sign(Type, Data, Key) ->
+    <<Ret:8, Signature/binary>> = control(rsa_sign_digest_type(Type), [Data,Key]),
+    case Ret of
+	1 -> Signature;
+	0 -> erlang:error(badkey, [Type,Data,Key])
+    end.
+
+rsa_sign_digest_type(md5) -> ?RSA_SIGN_MD5;
+rsa_sign_digest_type(sha) -> ?RSA_SIGN_SHA;
+rsa_sign_digest_type(Bad) -> erlang:error(badarg, [Bad]).
+
+%%
+%%  rsa_public_encrypt
+%%  rsa_private_decrypt
+
+%% Binary, Key = [E,N]
+rsa_public_encrypt(BinMesg, Key, Padding) ->
+    Size = iolist_size(BinMesg),
+    <<Ret:8, Signature/binary>> = 
+	control(?RSA_PUBLIC_ENCRYPT, [<<Size:32>>,BinMesg,Key,rsa_pad(Padding)]),
+    case Ret of
+	1 -> Signature;
+	0 -> erlang:error(encrypt_failed, [BinMesg,Key, Padding])
+    end.    
+
+%% Binary, Key = [E,N,D]
+rsa_private_decrypt(BinMesg, Key, Padding) ->
+    Size = iolist_size(BinMesg),
+    <<Ret:8, Signature/binary>> = 
+	control(?RSA_PRIVATE_DECRYPT, [<<Size:32>>,BinMesg,Key,rsa_pad(Padding)]),
+    case Ret of
+	1 -> Signature;
+	0 -> erlang:error(decrypt_failed, [BinMesg,Key, Padding])
+    end.    
+
+rsa_pad(rsa_pkcs1_padding) -> 1;
+rsa_pad(rsa_pkcs1_oaep_padding) -> 2;
+%% rsa_pad(rsa_sslv23_padding) -> 3;
+rsa_pad(rsa_no_padding) -> 0;
+rsa_pad(Bad) -> erlang:error(badarg, [Bad]).
+    
+%% Binary, Key = [E,N,D]
+rsa_private_encrypt(BinMesg, Key, Padding) ->
+    Size = iolist_size(BinMesg),
+    <<Ret:8, Signature/binary>> = 
+	control(?RSA_PRIVATE_ENCRYPT, [<<Size:32>>,BinMesg,Key,rsa_pad(Padding)]),
+    case Ret of
+	1 -> Signature;
+	0 -> erlang:error(encrypt_failed, [BinMesg,Key, Padding])
+    end.    
+
+%% Binary, Key = [E,N]
+rsa_public_decrypt(BinMesg, Key, Padding) ->
+    Size = iolist_size(BinMesg),
+    <<Ret:8, Signature/binary>> = 
+	control(?RSA_PUBLIC_DECRYPT, [<<Size:32>>,BinMesg,Key,rsa_pad(Padding)]),
+    case Ret of
+	1 -> Signature;
+	0 -> erlang:error(decrypt_failed, [BinMesg,Key, Padding])
+    end.
+    
+%%
+%% AES - with 128 or 256 bit key in cipher block chaining mode (CBC)
+%%
+
+aes_cbc_128_encrypt(Key, IVec, Data) ->
+    control(?AES_CBC_128_ENCRYPT, [Key, IVec, Data]).
+
+aes_cbc_128_decrypt(Key, IVec, Data) ->
+    control(?AES_CBC_128_DECRYPT, [Key, IVec, Data]).
+
+aes_cbc_256_encrypt(Key, IVec, Data) ->
+    control(?AES_CBC_256_ENCRYPT, [Key, IVec, Data]).
+
+aes_cbc_256_decrypt(Key, IVec, Data) ->
+    control(?AES_CBC_256_DECRYPT, [Key, IVec, Data]).
+
+%%
+%% aes_cbc_ivec(Data) -> binary()
+%%
+%% Returns the IVec to be used in the next iteration of
+%% aes_cbc_*_[encrypt|decrypt].
+%% IVec size: 16 bytes
+%%
+aes_cbc_ivec(Data) when is_binary(Data) ->
+    {_, IVec} = split_binary(Data, size(Data) - 16),
+    IVec;
+aes_cbc_ivec(Data) when is_list(Data) ->
+    aes_cbc_ivec(list_to_binary(Data)).
+
+
+%%
+%% XOR - xor to iolists and return a binary
+%% NB doesn't check that they are the same size, just concatenates
+%% them and sends them to the driver
+%%
+exor(A, B) ->
+    control(?XOR, [A, B]).
+
+%%
+%% RC4 - symmetric stream cipher
+%%
+rc4_encrypt(Key, Data) ->
+    control_bin(?RC4_ENCRYPT, Key, Data).
+
+rc4_set_key(Key) ->
+    control(?RC4_SET_KEY, Key).
+
+rc4_encrypt_with_state(State, Data) ->
+    <<Sz:32/integer-big-unsigned, S:Sz/binary, D/binary>> = 
+        control_bin(?RC4_ENCRYPT_WITH_STATE, State, Data),
+    {S, D}.
+
+%%
+%% RC2 - 40 bits block cipher
+%%
+rc2_40_cbc_encrypt(Key, IVec, Data) ->
+    control(?RC2_40_CBC_ENCRYPT, [Key, IVec, Data]).
+
+rc2_40_cbc_decrypt(Key, IVec, Data) ->
+    control(?RC2_40_CBC_DECRYPT, [Key, IVec, Data]).
+
+%%
+%% DH Diffie-Hellman functions
+%% 
+
+%% Generate (and check) Parameters is not documented because they are implemented
+%% for testing (and offline parameter generation) only.
+%% From the openssl doc: 
+%%  DH_generate_parameters() may run for several hours before finding a suitable prime.
+%% Thus dh_generate_parameters may in this implementation block 
+%% the emulator for several hours.
+%%
+%% usage: dh_generate_parameters(1024, 2 or 5) -> 
+%%    [Prime=mpint(), SharedGenerator=mpint()]
+dh_generate_parameters(PrimeLen, Generator) 
+  when is_integer(PrimeLen), is_integer(Generator) ->
+    case control(?DH_GENERATE_PARAMS, <<PrimeLen:32, Generator:32>>) of
+	<<0:8, _/binary>> ->
+	    erlang:error(generation_failed, [PrimeLen,Generator]);
+	<<1:8, PLen0:32, _:PLen0/binary, GLen0:32,_:GLen0/binary>> = Bin -> 
+	    PLen = PLen0+4, 
+	    GLen = GLen0+4,
+	    <<_:8, PBin:PLen/binary,GBin:GLen/binary>> = Bin,
+	    [PBin, GBin]
+    end.
+
+%% Checks that the DHParameters are ok.
+%% DHParameters = [P (Prime)= mpint(), G(Generator) = mpint()]
+dh_check(DHParameters) ->
+    case control(?DH_CHECK, DHParameters) of
+	<<0:32>>  -> ok;
+	<<_:24,_:1,_:1,_:1,1:1>> -> not_prime;
+	<<_:24,_:1,_:1,1:1,0:1>> -> not_strong_prime;
+	<<_:24,_:1,1:1,0:1,0:1>> -> unable_to_check_generator;
+	<<_:24,1:1,0:1,0:1,0:1>> -> not_suitable_generator;
+	<<16#FFFF:32>> -> {error, check_failed};
+	<<X:32>>  -> {unknown, X}
+    end.
+
+%% DHParameters = [P (Prime)= mpint(), G(Generator) = mpint()]
+%% PrivKey = mpint()
+dh_generate_key(DHParameters) ->
+    dh_generate_key(<<0:32>>, DHParameters).
+dh_generate_key(PrivateKey, DHParameters) ->
+    case control(?DH_GENERATE_KEY, [PrivateKey, DHParameters]) of
+	<<0:8, _/binary>> ->
+	    erlang:error(generation_failed, [PrivateKey,DHParameters]);
+	Bin = <<1:8, PubLen0:32, _:PubLen0/binary, PrivLen0:32, _:PrivLen0/binary>> -> 
+	    PubLen = PubLen0+4, 
+	    PrivLen = PrivLen0+4,
+	    <<_:8, PubBin:PubLen/binary,PrivBin:PrivLen/binary>> = Bin,
+	    {PubBin, PrivBin}
+    end.
+
+%% DHParameters = [P (Prime)= mpint(), G(Generator) = mpint()]
+%% MyPrivKey, OthersPublicKey = mpint() 
+dh_compute_key(OthersPublicKey, MyPrivateKey, DHParameters) ->
+    case control(?DH_COMPUTE_KEY, [OthersPublicKey, MyPrivateKey, DHParameters]) of
+	<<0:8, _/binary>> ->
+	    erlang:error(computation_failed, [OthersPublicKey,MyPrivateKey,DHParameters]);
+	<<1:8, Binary/binary>> -> Binary
+    end.
+
+%%
+%%  LOCAL FUNCTIONS
+%%
+control_bin(Cmd, Key, Data) ->
+    Sz = iolist_size(Key),
+    control(Cmd, [<<Sz:32/integer-unsigned>>, Key, Data]).
+
+control(Cmd, Data) ->
+    Port = crypto_server:client_port(),
+    erlang:port_control(Port, Cmd, Data).
+
+
+%% sizehdr(N) ->
+%%     [(N bsr 24) band 255,
+%%      (N bsr 16) band 255,
+%%      (N bsr  8) band 255,
+%%      N band 255].
+
+%% Flat length of IOlist (or binary)
+%% flen(L) when binary(L) ->
+%%     size(L);
+%% flen(L) ->
+%%     flen(L, 0).
+
+%% flen([H| T], N) when list(H) ->
+%%     flen(H, flen(T, N));
+%% flen([H| T], N) when binary(H) ->
+%%     flen(T, N + size(H));
+%% flen([H| T], N) when integer(H), 0 =< H, H =<  255 ->
+%%     flen(T, N + 1);
+%% flen([], N) ->
+%%     N.
+
+%% large integer in a binary with 32bit length
+%% MP representaion  (SSH2)
+mpint(X) when X < 0 ->
+    case X of
+	-1 ->
+	    <<0,0,0,1,16#ff>>;	    
+       _ ->
+	    mpint_neg(X,0,[])
+    end;
+mpint(X) ->
+    case X of 
+	0 ->
+	    <<0,0,0,0>>;
+	_ ->
+	    mpint_pos(X,0,[])
+    end.
+
+-define(UINT32(X),   X:32/unsigned-big-integer).
+
+mpint_neg(-1,I,Ds=[MSB|_]) ->
+    if MSB band 16#80 =/= 16#80 ->
+	    <<?UINT32((I+1)), (list_to_binary([255|Ds]))/binary>>;
+       true ->
+	    (<<?UINT32(I), (list_to_binary(Ds))/binary>>)
+    end;
+mpint_neg(X,I,Ds)  ->
+    mpint_neg(X bsr 8,I+1,[(X band 255)|Ds]).
+    
+mpint_pos(0,I,Ds=[MSB|_]) ->
+    if MSB band 16#80 == 16#80 ->
+	    <<?UINT32((I+1)), (list_to_binary([0|Ds]))/binary>>;
+       true ->
+	    (<<?UINT32(I), (list_to_binary(Ds))/binary>>)
+    end;
+mpint_pos(X,I,Ds) ->
+    mpint_pos(X bsr 8,I+1,[(X band 255)|Ds]).
+
+%% int from integer in a binary with 32bit length
+erlint(<<MPIntSize:32/integer,MPIntValue/binary>>) ->
+    Bits= MPIntSize * 8,
+    <<Integer:Bits/integer>> = MPIntValue,
+    Integer.