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Diffstat (limited to 'lib/crypto/src/crypto.erl')
| -rw-r--r-- | lib/crypto/src/crypto.erl | 665 |
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. |