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| author | Jeffrey Walton <noloader@gmail.com> | 2016-12-13 16:20:41 -0500 |
|---|---|---|
| committer | Jeffrey Walton <noloader@gmail.com> | 2016-12-13 16:20:41 -0500 |
| commit | cecf719fcd8cde0724567d4b38360daae52b4597 (patch) | |
| tree | eb1d45b7c9911f4fef3e32bbe1e91e584ee04b39 /eccrypto.cpp | |
| parent | 1a17ade299c3a05e5a63a8cb3f390d21845c21c6 (diff) | |
| download | cryptopp-git-cecf719fcd8cde0724567d4b38360daae52b4597.tar.gz | |
Add German digital signature algorithm (ECGDSA) (Issue 113)
Also see ISO/IEC 15946 and http://www.teletrust.de/fileadmin/files/oid/ecgdsa_final.pdf
Diffstat (limited to 'eccrypto.cpp')
| -rw-r--r-- | eccrypto.cpp | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/eccrypto.cpp b/eccrypto.cpp index 49f24367..c1a9c7e0 100644 --- a/eccrypto.cpp +++ b/eccrypto.cpp @@ -715,6 +715,77 @@ void DL_PrivateKey_EC<EC>::DEREncodePrivateKey(BufferedTransformation &bt) const privateKey.MessageEnd();
}
+// ******************************************************************
+
+template <class EC>
+void DL_PublicKey_ECGDSA_ISO15946<EC>::BERDecodePublicKey(BufferedTransformation &bt, bool parametersPresent, size_t size)
+{
+ CRYPTOPP_UNUSED(parametersPresent);
+
+ typename EC::Point P;
+ if (!this->GetGroupParameters().GetCurve().DecodePoint(P, bt, size))
+ BERDecodeError();
+ this->SetPublicElement(P);
+}
+
+template <class EC>
+void DL_PublicKey_ECGDSA_ISO15946<EC>::DEREncodePublicKey(BufferedTransformation &bt) const
+{
+ this->GetGroupParameters().GetCurve().EncodePoint(bt, this->GetPublicElement(), this->GetGroupParameters().GetPointCompression());
+}
+
+// ******************************************************************
+
+template <class EC>
+void DL_PrivateKey_ECGDSA_ISO15946<EC>::BERDecodePrivateKey(BufferedTransformation &bt, bool parametersPresent, size_t size)
+{
+ CRYPTOPP_UNUSED(size);
+ BERSequenceDecoder seq(bt);
+ word32 version;
+ BERDecodeUnsigned<word32>(seq, version, INTEGER, 1, 1); // check version
+
+ BERGeneralDecoder dec(seq, OCTET_STRING);
+ if (!dec.IsDefiniteLength())
+ BERDecodeError();
+ Integer x;
+ x.Decode(dec, (size_t)dec.RemainingLength());
+ dec.MessageEnd();
+ if (!parametersPresent && seq.PeekByte() != (CONTEXT_SPECIFIC | CONSTRUCTED | 0))
+ BERDecodeError();
+ if (!seq.EndReached() && seq.PeekByte() == (CONTEXT_SPECIFIC | CONSTRUCTED | 0))
+ {
+ BERGeneralDecoder parameters(seq, CONTEXT_SPECIFIC | CONSTRUCTED | 0);
+ this->AccessGroupParameters().BERDecode(parameters);
+ parameters.MessageEnd();
+ }
+ if (!seq.EndReached())
+ {
+ // skip over the public element
+ SecByteBlock subjectPublicKey;
+ unsigned int unusedBits;
+ BERGeneralDecoder publicKey(seq, CONTEXT_SPECIFIC | CONSTRUCTED | 1);
+ BERDecodeBitString(publicKey, subjectPublicKey, unusedBits);
+ publicKey.MessageEnd();
+ Element Q;
+ if (!(unusedBits == 0 && this->GetGroupParameters().GetCurve().DecodePoint(Q, subjectPublicKey, subjectPublicKey.size())))
+ BERDecodeError();
+ }
+ seq.MessageEnd();
+
+ this->SetPrivateExponent(x);
+}
+
+template <class EC>
+void DL_PrivateKey_ECGDSA_ISO15946<EC>::DEREncodePrivateKey(BufferedTransformation &bt) const
+{
+ DERSequenceEncoder privateKey(bt);
+ DEREncodeUnsigned<word32>(privateKey, 1); // version
+ // SEC 1 ver 1.0 says privateKey (m_d) has the same length as order of the curve
+ // this will be changed to order of base point in a future version
+ this->GetPrivateExponent().DEREncodeAsOctetString(privateKey, this->GetGroupParameters().GetSubgroupOrder().ByteCount());
+ privateKey.MessageEnd();
+}
+
NAMESPACE_END
#endif
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