%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2008-2010. 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(public_key).
-include("public_key.hrl").
-export([pem_decode/1, pem_encode/1,
der_decode/2, der_encode/2,
pem_entry_decode/1,
pem_entry_decode/2,
pem_entry_encode/2,
pem_entry_encode/3,
pkix_decode_cert/2, pkix_encode/3,
encrypt_private/2, encrypt_private/3,
decrypt_private/2, decrypt_private/3,
encrypt_public/2, encrypt_public/3,
decrypt_public/2, decrypt_public/3,
sign/3, verify/4,
pkix_sign/2, pkix_verify/2,
pkix_is_self_signed/1,
pkix_is_fixed_dh_cert/1,
pkix_is_issuer/2,
pkix_issuer_id/2,
pkix_normalize_name/1,
pkix_path_validation/3
]).
%% Deprecated
-export([decode_private_key/1, decode_private_key/2, pem_to_der/1]).
-deprecated({pem_to_der, 1, next_major_release}).
-deprecated({decode_private_key, 1, next_major_release}).
-deprecated({decode_private_key, 2, next_major_release}).
-type rsa_public_key() :: #'RSAPublicKey'{}.
-type rsa_private_key() :: #'RSAPrivateKey'{}.
-type dsa_private_key() :: #'DSAPrivateKey'{}.
-type dsa_public_key() :: {integer(), #'Dss-Parms'{}}.
-type rsa_padding() :: 'rsa_pkcs1_padding' | 'rsa_pkcs1_oaep_padding'
| 'rsa_no_padding'.
-type public_crypt_options() :: [{rsa_pad, rsa_padding()}].
-type rsa_digest_type() :: 'md5' | 'sha'.
-type dss_digest_type() :: 'none' | 'sha'.
-define(UINT32(X), X:32/unsigned-big-integer).
%%====================================================================
%% API
%%====================================================================
%%--------------------------------------------------------------------
-spec pem_decode(binary()) -> [pem_entry()].
%%
%% Description: Decode PEM binary data and return
%% entries as asn1 der encoded entities.
%%--------------------------------------------------------------------
pem_decode(PemBin) when is_binary(PemBin) ->
pubkey_pem:decode(PemBin).
%%--------------------------------------------------------------------
-spec pem_encode([pem_entry()]) -> binary().
%%
%% Description: Creates a PEM binary.
%%--------------------------------------------------------------------
pem_encode(PemEntries) when is_list(PemEntries) ->
iolist_to_binary(pubkey_pem:encode(PemEntries)).
%%--------------------------------------------------------------------
-spec pem_entry_decode(pem_entry(), [string()]) -> term().
%
%% Description: Decodes a pem entry. pem_decode/1 returns a list of
%% pem entries.
%%--------------------------------------------------------------------
pem_entry_decode({Asn1Type, Der, not_encrypted}) when is_atom(Asn1Type),
is_binary(Der) ->
der_decode(Asn1Type, Der).
pem_entry_decode({Asn1Type, Der, not_encrypted}, _) when is_atom(Asn1Type),
is_binary(Der) ->
der_decode(Asn1Type, Der);
pem_entry_decode({Asn1Type, CryptDer, {Cipher, Salt}} = PemEntry,
Password) when is_atom(Asn1Type),
is_binary(CryptDer),
is_list(Cipher),
is_binary(Salt),
erlang:byte_size(Salt) == 8
->
Der = pubkey_pem:decipher(PemEntry, Password),
der_decode(Asn1Type, Der).
%%--------------------------------------------------------------------
-spec pem_entry_encode(pki_asn1_type(), term()) -> pem_entry().
-spec pem_entry_encode(pki_asn1_type(), term(),
{{Cipher :: string(), Salt :: binary()}, string()}) ->
pem_entry().
%
%% Description: Creates a pem entry that can be feed to pem_encode/1.
%%--------------------------------------------------------------------
pem_entry_encode(Asn1Type, Entity) when is_atom(Asn1Type) ->
Der = der_encode(Asn1Type, Entity),
{Asn1Type, Der, not_encrypted}.
pem_entry_encode(Asn1Type, Entity,
{{Cipher, Salt}= CipherInfo, Password}) when is_atom(Asn1Type),
is_list(Cipher),
is_binary(Salt),
erlang:byte_size(Salt) == 8,
is_list(Password)->
Der = der_encode(Asn1Type, Entity),
DecryptDer = pubkey_pem:cipher(Der, CipherInfo, Password),
{Asn1Type, DecryptDer, CipherInfo}.
%%--------------------------------------------------------------------
-spec der_decode(asn1_type(), der_encoded()) -> term().
%%
%% Description: Decodes a public key asn1 der encoded entity.
%%--------------------------------------------------------------------
der_decode(Asn1Type, Der) when is_atom(Asn1Type), is_binary(Der) ->
try
{ok, Decoded} = 'OTP-PUB-KEY':decode(Asn1Type, Der),
Decoded
catch
error:{badmatch, {error, _}} = Error ->
erlang:error(Error)
end.
%%--------------------------------------------------------------------
-spec der_encode(asn1_type(), term()) -> der_encoded().
%%
%% Description: Encodes a public key entity with asn1 DER encoding.
%%--------------------------------------------------------------------
der_encode(Asn1Type, Entity) when is_atom(Asn1Type) ->
try
{ok, Encoded} = 'OTP-PUB-KEY':encode(Asn1Type, Entity),
iolist_to_binary(Encoded)
catch
error:{badmatch, {error, _}} = Error ->
erlang:error(Error)
end.
%%--------------------------------------------------------------------
-spec pkix_decode_cert(der_encoded(), plain | otp) ->
#'Certificate'{} | #'OTPCertificate'{}.
%%
%% Description: Decodes an asn1 der encoded pkix certificate. The otp
%% option will use the customized asn1 specification OTP-PKIX.asn1 for
%% decoding and also recursively decode most of the standard
%% extensions.
%% --------------------------------------------------------------------
pkix_decode_cert(DerCert, plain) when is_binary(DerCert) ->
der_decode('Certificate', DerCert);
pkix_decode_cert(DerCert, otp) when is_binary(DerCert) ->
try
{ok, #'OTPCertificate'{}= Cert} =
pubkey_cert_records:decode_cert(DerCert),
Cert
catch
error:{badmatch, {error, _}} = Error ->
erlang:error(Error)
end.
%%--------------------------------------------------------------------
-spec pkix_encode(asn1_type(), term(), otp | plain) -> der_encoded().
%%
%% Description: Der encodes a certificate or part of a certificate.
%% This function must be used for encoding certificates or parts of certificates
%% that are decoded with the otp format, whereas for the plain format this
%% function will only call der_encode/2.
%%--------------------------------------------------------------------
pkix_encode(Asn1Type, Term, plain) when is_atom(Asn1Type) ->
der_encode(Asn1Type, Term);
pkix_encode(Asn1Type, Term0, otp) when is_atom(Asn1Type) ->
Term = pubkey_cert_records:transform(Term0, encode),
der_encode(Asn1Type, Term).
%%--------------------------------------------------------------------
-spec decrypt_private(CipherText :: binary(), rsa_private_key()) ->
PlainText :: binary().
-spec decrypt_private(CipherText :: binary(), rsa_private_key(),
public_crypt_options()) -> PlainText :: binary().
%%
%% Description: Public key decryption using the private key.
%%--------------------------------------------------------------------
decrypt_private(CipherText, Key) ->
decrypt_private(CipherText, Key, []).
decrypt_private(CipherText,
#'RSAPrivateKey'{modulus = N,publicExponent = E,
privateExponent = D},
Options) when is_binary(CipherText),
is_list(Options) ->
Padding = proplists:get_value(rsa_pad, Options, rsa_pkcs1_padding),
crypto:rsa_private_decrypt(CipherText,
[crypto:mpint(E), crypto:mpint(N),
crypto:mpint(D)], Padding).
%%--------------------------------------------------------------------
-spec decrypt_public(CipherText :: binary(), rsa_public_key() | rsa_private_key()) ->
PlainText :: binary().
-spec decrypt_public(CipherText :: binary(), rsa_public_key() | rsa_private_key(),
public_crypt_options()) -> PlainText :: binary().
%% NOTE: The rsa_private_key() is not part of the documented API it is
%% here for testing purposes, in a real situation this is not a relevant
%% thing to do.
%%
%% Description: Public key decryption using the public key.
%%--------------------------------------------------------------------
decrypt_public(CipherText, Key) ->
decrypt_public(CipherText, Key, []).
decrypt_public(CipherText, #'RSAPublicKey'{modulus = N, publicExponent = E},
Options) when is_binary(CipherText), is_list(Options) ->
decrypt_public(CipherText, N,E, Options);
decrypt_public(CipherText,#'RSAPrivateKey'{modulus = N, publicExponent = E},
Options) when is_binary(CipherText), is_list(Options) ->
decrypt_public(CipherText, N,E, Options).
%%--------------------------------------------------------------------
-spec encrypt_public(PlainText :: binary(), rsa_public_key() | rsa_private_key()) ->
CipherText :: binary().
-spec encrypt_public(PlainText :: binary(), rsa_public_key() | rsa_private_key(),
public_crypt_options()) -> CipherText :: binary().
%% NOTE: The rsa_private_key() is not part of the documented API it is
%% here for testing purposes, in a real situation this is not a relevant
%% thing to do.
%%
%% Description: Public key encryption using the public key.
%%--------------------------------------------------------------------
encrypt_public(PlainText, Key) ->
encrypt_public(PlainText, Key, []).
encrypt_public(PlainText, #'RSAPublicKey'{modulus=N,publicExponent=E},
Options) when is_binary(PlainText), is_list(Options) ->
encrypt_public(PlainText, N,E, Options);
encrypt_public(PlainText, #'RSAPrivateKey'{modulus=N,publicExponent=E},
Options) when is_binary(PlainText), is_list(Options) ->
encrypt_public(PlainText, N,E, Options).
%%--------------------------------------------------------------------
-spec encrypt_private(PlainText :: binary(), rsa_private_key()) ->
CipherText :: binary().
-spec encrypt_private(PlainText :: binary(), rsa_private_key(),
public_crypt_options()) -> CipherText :: binary().
%%
%% Description: Public key encryption using the private key.
%%--------------------------------------------------------------------
encrypt_private(PlainText, Key) ->
encrypt_private(PlainText, Key, []).
encrypt_private(PlainText, #'RSAPrivateKey'{modulus = N,
publicExponent = E,
privateExponent = D},
Options) when is_binary(PlainText), is_list(Options) ->
Padding = proplists:get_value(rsa_pad, Options, rsa_pkcs1_padding),
crypto:rsa_private_encrypt(PlainText, [crypto:mpint(E),
crypto:mpint(N),
crypto:mpint(D)], Padding).
%%--------------------------------------------------------------------
-spec sign(PlainTextOrDigest :: binary(), rsa_digest_type() | dss_digest_type(),
rsa_private_key() |
dsa_private_key()) -> Signature :: binary().
%%
%% Description: Create digital signature.
%%--------------------------------------------------------------------
sign(PlainText, DigestType, #'RSAPrivateKey'{modulus = N, publicExponent = E,
privateExponent = D})
when is_binary(PlainText),
DigestType == md5;
DigestType == sha ->
crypto:rsa_sign(DigestType, sized_binary(PlainText), [crypto:mpint(E),
crypto:mpint(N),
crypto:mpint(D)]);
sign(Digest, none, #'DSAPrivateKey'{p = P, q = Q, g = G, x = X})
when is_binary(Digest)->
crypto:dss_sign(none, Digest,
[crypto:mpint(P), crypto:mpint(Q),
crypto:mpint(G), crypto:mpint(X)]);
sign(PlainText, sha, #'DSAPrivateKey'{p = P, q = Q, g = G, x = X})
when is_binary(PlainText) ->
crypto:dss_sign(sized_binary(PlainText),
[crypto:mpint(P), crypto:mpint(Q),
crypto:mpint(G), crypto:mpint(X)]).
%%--------------------------------------------------------------------
-spec verify(PlainTextOrDigest :: binary(), rsa_digest_type() | dss_digest_type(),
Signature :: binary(), rsa_public_key()
| dsa_public_key()) -> boolean().
%%
%% Description: Verifies a digital signature.
%%--------------------------------------------------------------------
verify(PlainText, DigestType, Signature,
#'RSAPublicKey'{modulus = Mod, publicExponent = Exp})
when is_binary (PlainText), DigestType == sha; DigestType == md5 ->
crypto:rsa_verify(DigestType,
sized_binary(PlainText),
sized_binary(Signature),
[crypto:mpint(Exp), crypto:mpint(Mod)]);
verify(Digest, none, Signature, {Key, #'Dss-Parms'{p = P, q = Q, g = G}})
when is_integer(Key), is_binary(Digest), is_binary(Signature) ->
crypto:dss_verify(none,
Digest,
sized_binary(Signature),
[crypto:mpint(P), crypto:mpint(Q),
crypto:mpint(G), crypto:mpint(Key)]);
verify(PlainText, sha, Signature, {Key, #'Dss-Parms'{p = P, q = Q, g = G}})
when is_integer(Key), is_binary(PlainText), is_binary(Signature) ->
crypto:dss_verify(sized_binary(PlainText),
sized_binary(Signature),
[crypto:mpint(P), crypto:mpint(Q),
crypto:mpint(G), crypto:mpint(Key)]).
%%--------------------------------------------------------------------
-spec pkix_sign(#'OTPTBSCertificate'{},
rsa_private_key() | dsa_private_key()) -> der_encoded().
%%
%% Description: Sign a pkix x.509 certificate. Returns the corresponding
%% der encoded 'Certificate'{}
%%--------------------------------------------------------------------
pkix_sign(#'OTPTBSCertificate'{signature =
#'SignatureAlgorithm'{algorithm = Alg}
= SigAlg} = TBSCert, Key) ->
Msg = pkix_encode('OTPTBSCertificate', TBSCert, otp),
DigestType = pubkey_cert:digest_type(Alg),
Signature = sign(Msg, DigestType, Key),
Cert = #'OTPCertificate'{tbsCertificate= TBSCert,
signatureAlgorithm = SigAlg,
signature = {0, Signature}
},
pkix_encode('OTPCertificate', Cert, otp).
%%--------------------------------------------------------------------
-spec pkix_verify(der_encoded(), rsa_public_key()|
dsa_public_key()) -> boolean().
%%
%% Description: Verify pkix x.509 certificate signature.
%%--------------------------------------------------------------------
pkix_verify(DerCert, {Key, #'Dss-Parms'{}} = DSAKey)
when is_binary(DerCert), is_integer(Key) ->
{DigestType, PlainText, Signature} = pubkey_cert:verify_data(DerCert),
verify(PlainText, DigestType, Signature, DSAKey);
pkix_verify(DerCert, #'RSAPublicKey'{} = RSAKey)
when is_binary(DerCert) ->
{DigestType, PlainText, Signature} = pubkey_cert:verify_data(DerCert),
verify(PlainText, DigestType, Signature, RSAKey).
%%--------------------------------------------------------------------
-spec pkix_is_issuer(Cert :: der_encoded()| #'OTPCertificate'{},
IssuerCert :: der_encoded()|
#'OTPCertificate'{}) -> boolean().
%%
%% Description: Checks if <IssuerCert> issued <Cert>.
%%--------------------------------------------------------------------
pkix_is_issuer(Cert, IssuerCert) when is_binary(Cert) ->
OtpCert = pkix_decode_cert(Cert, otp),
pkix_is_issuer(OtpCert, IssuerCert);
pkix_is_issuer(Cert, IssuerCert) when is_binary(IssuerCert) ->
OtpIssuerCert = pkix_decode_cert(IssuerCert, otp),
pkix_is_issuer(Cert, OtpIssuerCert);
pkix_is_issuer(#'OTPCertificate'{tbsCertificate = TBSCert},
#'OTPCertificate'{tbsCertificate = Candidate}) ->
pubkey_cert:is_issuer(TBSCert#'OTPTBSCertificate'.issuer,
Candidate#'OTPTBSCertificate'.subject).
%%--------------------------------------------------------------------
-spec pkix_is_self_signed(der_encoded()| #'OTPCertificate'{}) -> boolean().
%%
%% Description: Checks if a Certificate is self signed.
%%--------------------------------------------------------------------
pkix_is_self_signed(#'OTPCertificate'{} = OTPCert) ->
pubkey_cert:is_self_signed(OTPCert);
pkix_is_self_signed(Cert) when is_binary(Cert) ->
OtpCert = pkix_decode_cert(Cert, otp),
pkix_is_self_signed(OtpCert).
%%--------------------------------------------------------------------
-spec pkix_is_fixed_dh_cert(der_encoded()| #'OTPCertificate'{}) -> boolean().
%%
%% Description: Checks if a Certificate is a fixed Diffie-Hellman Cert.
%%--------------------------------------------------------------------
pkix_is_fixed_dh_cert(#'OTPCertificate'{} = OTPCert) ->
pubkey_cert:is_fixed_dh_cert(OTPCert);
pkix_is_fixed_dh_cert(Cert) when is_binary(Cert) ->
OtpCert = pkix_decode_cert(Cert, otp),
pkix_is_fixed_dh_cert(OtpCert).
%%--------------------------------------------------------------------
-spec pkix_issuer_id(der_encoded()| #'OTPCertificate'{},
IssuedBy :: self | other) ->
{ok, {SerialNr :: integer(),
Issuer :: {rdnSequence,
[#'AttributeTypeAndValue'{}]}}}
| {error, Reason :: term()}.
%
%% Description: Returns the issuer id.
%%--------------------------------------------------------------------
pkix_issuer_id(#'OTPCertificate'{} = OtpCert, self) ->
pubkey_cert:issuer_id(OtpCert, self);
pkix_issuer_id(#'OTPCertificate'{} = OtpCert, other) ->
pubkey_cert:issuer_id(OtpCert, other);
pkix_issuer_id(Cert, Signed) when is_binary(Cert) ->
OtpCert = pkix_decode_cert(Cert, otp),
pkix_issuer_id(OtpCert, Signed).
%%--------------------------------------------------------------------
-spec pkix_normalize_name({rdnSequence,
[#'AttributeTypeAndValue'{}]}) ->
{rdnSequence,
[#'AttributeTypeAndValue'{}]}.
%%
%% Description: Normalizes a issuer name so that it can be easily
%% compared to another issuer name.
%%--------------------------------------------------------------------
pkix_normalize_name(Issuer) ->
pubkey_cert:normalize_general_name(Issuer).
%%--------------------------------------------------------------------
-spec pkix_path_validation(der_encoded()| #'OTPCertificate'{} | atom(),
CertChain :: [der_encoded()] ,
Options :: list()) ->
{ok, {PublicKeyInfo :: term(),
PolicyTree :: term()}} |
{error, {bad_cert, Reason :: term()}}.
%% Description: Performs a basic path validation according to RFC 5280.
%%--------------------------------------------------------------------
pkix_path_validation(PathErr, [Cert | Chain], Options0) when is_atom(PathErr)->
{VerifyFun, Userstat0} =
proplists:get_value(verify_fun, Options0, ?DEFAULT_VERIFYFUN),
Otpcert = pkix_decode_cert(Cert, otp),
Reason = {bad_cert, PathErr},
try VerifyFun(Otpcert, Reason, Userstat0) of
{valid, Userstate} ->
Options = proplists:delete(verify_fun, Options0),
pkix_path_validation(Otpcert, Chain, [{verify_fun,
{VerifyFun, Userstate}}| Options]);
{fail, _} ->
{error, Reason}
catch
_:_ ->
{error, Reason}
end;
pkix_path_validation(TrustedCert, CertChain, Options) when
is_binary(TrustedCert) -> OtpCert = pkix_decode_cert(TrustedCert,
otp), pkix_path_validation(OtpCert, CertChain, Options);
pkix_path_validation(#'OTPCertificate'{} = TrustedCert, CertChain, Options)
when is_list(CertChain), is_list(Options) ->
MaxPathDefault = length(CertChain),
ValidationState = pubkey_cert:init_validation_state(TrustedCert,
MaxPathDefault,
Options),
path_validation(CertChain, ValidationState).
%%--------------------------------------------------------------------
%%% Internal functions
%%--------------------------------------------------------------------
encrypt_public(PlainText, N, E, Options)->
Padding = proplists:get_value(rsa_pad, Options, rsa_pkcs1_padding),
crypto:rsa_public_encrypt(PlainText, [crypto:mpint(E),crypto:mpint(N)],
Padding).
decrypt_public(CipherText, N,E, Options) ->
Padding = proplists:get_value(rsa_pad, Options, rsa_pkcs1_padding),
crypto:rsa_public_decrypt(CipherText,[crypto:mpint(E), crypto:mpint(N)],
Padding).
path_validation([], #path_validation_state{working_public_key_algorithm
= Algorithm,
working_public_key =
PublicKey,
working_public_key_parameters
= PublicKeyParams,
valid_policy_tree = Tree
}) ->
{ok, {{Algorithm, PublicKey, PublicKeyParams}, Tree}};
path_validation([DerCert | Rest], ValidationState = #path_validation_state{
max_path_length = Len}) when Len >= 0 ->
try validate(DerCert,
ValidationState#path_validation_state{last_cert=Rest=:=[]}) of
#path_validation_state{} = NewValidationState ->
path_validation(Rest, NewValidationState)
catch
throw:Reason ->
{error, Reason}
end;
path_validation([DerCert | _] = Path,
#path_validation_state{user_state = UserState0,
verify_fun = VerifyFun} =
ValidationState) ->
Reason = {bad_cert, max_path_length_reached},
OtpCert = pkix_decode_cert(DerCert, otp),
try VerifyFun(OtpCert, Reason, UserState0) of
{valid, UserState} ->
path_validation(Path,
ValidationState#path_validation_state{
max_path_length = 0,
user_state = UserState});
{fail, _} ->
{error, Reason}
catch
_:_ ->
{error, Reason}
end.
validate(DerCert, #path_validation_state{working_issuer_name = Issuer,
working_public_key = Key,
working_public_key_parameters =
KeyParams,
permitted_subtrees = Permit,
excluded_subtrees = Exclude,
last_cert = Last,
user_state = UserState0,
verify_fun = VerifyFun} =
ValidationState0) ->
OtpCert = pkix_decode_cert(DerCert, otp),
UserState1 = pubkey_cert:validate_time(OtpCert, UserState0, VerifyFun),
UserState2 = pubkey_cert:validate_issuer(OtpCert, Issuer, UserState1, VerifyFun),
UserState3 = pubkey_cert:validate_names(OtpCert, Permit, Exclude, Last,
UserState2,VerifyFun),
UserState4 = pubkey_cert:validate_revoked_status(OtpCert, UserState3, VerifyFun),
{ValidationState1, UserState5} =
pubkey_cert:validate_extensions(OtpCert, ValidationState0, UserState4,
VerifyFun),
%% We want the key_usage extension to be checked before we validate
%% the signature.
UserState6 = pubkey_cert:validate_signature(OtpCert, DerCert,
Key, KeyParams, UserState5, VerifyFun),
UserState = case Last of
false ->
pubkey_cert:verify_fun(OtpCert, valid, UserState6, VerifyFun);
true ->
pubkey_cert:verify_fun(OtpCert, valid_peer,
UserState6, VerifyFun)
end,
ValidationState =
ValidationState1#path_validation_state{user_state = UserState},
pubkey_cert:prepare_for_next_cert(OtpCert, ValidationState).
sized_binary(Binary) ->
Size = size(Binary),
<<?UINT32(Size), Binary/binary>>.
%%--------------------------------------------------------------------
%%% Deprecated functions
%%--------------------------------------------------------------------
pem_to_der(CertSource) ->
{ok, Bin} = file:read_file(CertSource),
{ok, pubkey_pem:decode(Bin)}.
decode_private_key(KeyInfo) ->
decode_private_key(KeyInfo, no_passwd).
decode_private_key(KeyInfo = {'RSAPrivateKey', _, _}, Password) ->
DerEncoded = pubkey_pem:decode_key(KeyInfo, Password),
'OTP-PUB-KEY':decode('RSAPrivateKey', DerEncoded);
decode_private_key(KeyInfo = {'DSAPrivateKey', _, _}, Password) ->
DerEncoded = pubkey_pem:decode_key(KeyInfo, Password),
'OTP-PUB-KEY':decode('DSAPrivateKey', DerEncoded).