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Hello everyone, I'm working on a Delphi project that requires signing a request signature with RSASSA-PSS algorithm. In my implementation, I initialize the signing context with EVP_DigestSignInit using SHA-256. However, when I attempt to set the salt length with EVP_PKEY_CTX_set_rsa_pss_saltlen(PSSCtx, 32), it consistently returns an error. I'm using the OverByteIcsLIBEAY.pas functions. Params I need to use for the signature: Hash algorithm: SHA-256 Mask generation function: MGF1 Mask generation algorithm: SHA-256 Salt length: 32 bytes (= 256 bits, same as the hash length) Trailer field: 1 Has anyone here encountered similar issues with RSASSA-PSS in OpenSSL, particularly with setting the salt length? Any advice on handling this setup in Delphi would be greatly appreciated! Thanks in advance! function TIsabelData.SignData(const AData: TBytes; APrivateKey: PEVP_PKEY): string; var SignCtx: PEVP_MD_CTX; PSSCtx: PEVP_PKEY_CTX; Sig: TBytes; SigLen: Cardinal; ErrCode: Cardinal; begin if EVP_PKEY_base_id(APrivateKey) <> EVP_PKEY_RSA then raise Exception.Create('The provided key is not an RSA key'); SignCtx := EVP_MD_CTX_create; PSSCtx := nil; try if EVP_DigestSignInit(SignCtx, @PSSCtx, EVP_sha256, nil, APrivateKey) <> 1 then raise Exception.Create('Error initializing digest sign'); if EVP_PKEY_CTX_set_rsa_padding(PSSCtx, RSA_PKCS1_PSS_PADDING) <= 0 then raise Exception.Create('Error setting RSA PSS padding'); if EVP_PKEY_CTX_set_rsa_pss_saltlen(PSSCtx, 32) <= 0 then begin ErrCode := ERR_get_error; raise Exception.Create('Error setting RSA PSS salt length: ' + string(ERR_reason_error_string(ErrCode))); end; if EVP_PKEY_CTX_set_rsa_mgf1_md(PSSCtx, EVP_sha256) <= 0 then raise Exception.Create('Error setting MGF1 to SHA256'); if EVP_DigestSignUpdate(SignCtx, @AData[0], Length(AData)) <> 1 then raise Exception.Create('Error updating digest sign'); SigLen := 0; if EVP_DigestSignFinal(SignCtx, nil, @SigLen) <> 1 then raise Exception.Create('Error finalizing digest sign'); SetLength(Sig, SigLen); if EVP_DigestSignFinal(SignCtx, @Sig[0], @SigLen) <> 1 then raise Exception.Create('Error finalizing digest sign'); Result := TNetEncoding.Base64.EncodeBytesToString(Sig); finally EVP_MD_CTX_free(SignCtx); EVP_PKEY_CTX_free(PSSCtx); end; end;