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Diffstat (limited to 'lib/ssl/src/ssl_pem.erl')
| -rw-r--r-- | lib/ssl/src/ssl_pem.erl | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/lib/ssl/src/ssl_pem.erl b/lib/ssl/src/ssl_pem.erl new file mode 100644 index 0000000000..0a1bf0f32a --- /dev/null +++ b/lib/ssl/src/ssl_pem.erl @@ -0,0 +1,147 @@ +%% +%% %CopyrightBegin% +%% +%% Copyright Ericsson AB 2003-2009. 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% +%% + +%% + +-module(ssl_pem). + +%%% Purpose: Reading and writing of PEM type encoded files for SSL. + +%% NB write_file/2 is only preliminary. + +%% PEM encoded files have the following structure: +%% +%% <text> +%% -----BEGIN SOMETHING-----<CR><LF> +%% <Base64 encoding line><CR><LF> +%% <Base64 encoding line><CR><LF> +%% ... +%% -----END SOMETHING-----<CR><LF> +%% <text> +%% +%% A file can contain several BEGIN/END blocks. Text lines between +%% blocks are ignored. + +-export([read_file/1, read_file/2, write_file/2]). + +%% Read a PEM file and return each decoding as a binary. + +read_file(File) -> + read_file(File, no_passwd). + +read_file(File, Passwd) -> + {ok, Fd} = file:open(File, [read]), + Result = decode_file(Fd, Passwd), + file:close(Fd), + Result. + +decode_file(Fd, Passwd) -> + decode_file(Fd, [], [], notag, [Passwd]). + +decode_file(Fd, _RLs, Ens, notag, Info) -> + case io:get_line(Fd, "") of + "-----BEGIN CERTIFICATE REQUEST-----" ++ _ -> + decode_file(Fd, [], Ens, cert_req, Info); + "-----BEGIN CERTIFICATE-----" ++ _ -> + decode_file(Fd, [], Ens, cert, Info); + "-----BEGIN RSA PRIVATE KEY-----" ++ _ -> + decode_file(Fd, [], Ens, rsa_private_key, Info); + eof -> + {ok, lists:reverse(Ens)}; + _ -> + decode_file(Fd, [], Ens, notag, Info) + end; +decode_file(Fd, RLs, Ens, Tag, Info0) -> + case io:get_line(Fd, "") of + "Proc-Type: 4,ENCRYPTED"++_ -> + Info = dek_info(Fd, Info0), + decode_file(Fd, RLs, Ens, Tag, Info); + "-----END" ++ _ -> % XXX sloppy + Cs = lists:flatten(lists:reverse(RLs)), + Bin = ssl_base64:join_decode(Cs), + case Info0 of + [Password, Cipher, SaltHex | Info1] -> + Decoded = decode_key(Bin, Password, Cipher, unhex(SaltHex)), + decode_file(Fd, [], [{Tag, Decoded}| Ens], notag, Info1); + _ -> + decode_file(Fd, [], [{Tag, Bin}| Ens], notag, Info0) + end; + eof -> + {ok, lists:reverse(Ens)}; + L -> + decode_file(Fd, [L|RLs], Ens, Tag, Info0) + end. + +dek_info(Fd, Info) -> + Line = io:get_line(Fd, ""), + [_, DekInfo0] = string:tokens(Line, ": "), + DekInfo1 = string:tokens(DekInfo0, ",\n"), + Info ++ DekInfo1. + +unhex(S) -> + unhex(S, []). + +unhex("", Acc) -> + lists:reverse(Acc); +unhex([D1, D2 | Rest], Acc) -> + unhex(Rest, [erlang:list_to_integer([D1, D2], 16) | Acc]). + +decode_key(Data, Password, "DES-CBC", Salt) -> + Key = password_to_key(Password, Salt, 8), + IV = Salt, + crypto:des_cbc_decrypt(Key, IV, Data); +decode_key(Data, Password, "DES-EDE3-CBC", Salt) -> + Key = password_to_key(Password, Salt, 24), + IV = Salt, + <<Key1:8/binary, Key2:8/binary, Key3:8/binary>> = Key, + crypto:des_ede3_cbc_decrypt(Key1, Key2, Key3, IV, Data). + +write_file(File, Ds) -> + file:write_file(File, encode_file(Ds)). + +encode_file(Ds) -> + [encode_file_1(D) || D <- Ds]. + +encode_file_1({cert, Bin}) -> + %% PKIX (X.509) + ["-----BEGIN CERTIFICATE-----\n", + ssl_base64:encode_split(Bin), + "-----END CERTIFICATE-----\n\n"]; +encode_file_1({cert_req, Bin}) -> + %% PKCS#10 + ["-----BEGIN CERTIFICATE REQUEST-----\n", + ssl_base64:encode_split(Bin), + "-----END CERTIFICATE REQUEST-----\n\n"]; +encode_file_1({rsa_private_key, Bin}) -> + %% PKCS#? + ["XXX Following key assumed not encrypted\n", + "-----BEGIN RSA PRIVATE KEY-----\n", + ssl_base64:encode_split(Bin), + "-----END RSA PRIVATE KEY-----\n\n"]. + +password_to_key(Data, Salt, KeyLen) -> + <<Key:KeyLen/binary, _/binary>> = + password_to_key(<<>>, Data, Salt, KeyLen, <<>>), + Key. + +password_to_key(_, _, _, Len, Acc) when Len =< 0 -> + Acc; +password_to_key(Prev, Data, Salt, Len, Acc) -> + M = crypto:md5([Prev, Data, Salt]), + password_to_key(M, Data, Salt, Len - byte_size(M), <<Acc/binary, M/binary>>). |