Hi all, I found that the default format is P1363. Since I am signing the message using crypto++ ecdsa, and verify the signature with Go, I need to change the signature format from P1363 to DER.
I referred to the document https://www.codeproject.com/Articles/25590/Cryptographic-Interoperability-Digital-Signatures However, the length below is 0, does anybody know if there is something wrong? // Determine size of required buffer auto length = DSAConvertSignatureFormat(NULL, 0, DSA_DER, (byte*)signatureP1363.c_str(), signatureP1363.size(), DSA_P1363); 王祥於 2018年7月18日星期三 UTC+8上午7時21分01秒寫道： > > Hi guys, > > > I tried to call DSAConvertSignatureFormat with the signature generated by > the two following ways, > ************ > byte signature[0x40]; > DSAConvertSignatureFormat(signature, sizeof(signature), DSA_DER, > (byte*)signatureDSA_DER.c_str(), signatureDSA_DER.size(), DSA_DER); > ************ > > the BERDecodeErr was thrown. > What is the format of the signatures generated in the following format? > > ************ > size_t siglen = signer.MaxSignatureLength(); > string signatureDSA_DER(siglen, 0x00); > siglen = signer.SignMessage(prng, (const byte*)content.c_str(), > content.size(), (byte*)&signatureDSA_DER[0]); > signatureDSA_DER.resize(siglen); > ************ > string signatureDSA_DER; > StringSource s(content, true /*pump all*/, > new SignerFilter(prng, > signer, > new StringSink(signatureDSA_DER) > ) // SignerFilter > ); // StringSource > ************ > > Best Regards, > -- You received this message because you are subscribed to "Crypto++ Users". More information about Crypto++ and this group is available at http://www.cryptopp.com and http://groups.google.com/forum/#!forum/cryptopp-users. --- You received this message because you are subscribed to the Google Groups "Crypto++ Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
