Hyperledger Fabric中的零知识证明

IdemixEnrollment idemixEnrollment = hfcaClient.idemixEnroll(x509enrollment, "idemixMSPID1");

func GetAttributeValue(stub ChaincodeStubInterface, attrName string) (value string, found bool, err error)

type ChaincodeStubInterface interface {
    // GetCreator returns `SignatureHeader.Creator` (e.g. an identity)
    // of the `SignedProposal`. This is the identity of the agent (or user)
    // submitting the transaction.
    GetCreator() ([]byte, error)
}

type ClientIdentity interface {

    // GetID returns the ID associated with the invoking identity.  This ID
    // is guaranteed to be unique within the MSP.
    GetID() (string, error)

    // Return the MSP ID of the client
    GetMSPID() (string, error)

    // GetAttributeValue returns the value of the client's attribute named `attrName`.
    // If the client possesses the attribute, `found` is true and `value` equals the
    // value of the attribute.
    // If the client does not possess the attribute, `found` is false and `value`
    // equals "".
    GetAttributeValue(attrName string) (value string, found bool, err error)

    // AssertAttributeValue verifies that the client has the attribute named `attrName`
    // with a value of `attrValue`; otherwise, an error is returned.
    AssertAttributeValue(attrName, attrValue string) error

    // GetX509Certificate returns the X509 certificate associated with the client,
    // or nil if it was not identified by an X509 certificate.
    GetX509Certificate() (*x509.Certificate, error)
}

package main
import (
"fmt"
"log"
    "os"
"strconv"
"strings"

"github.com/hyperledger/fabric-chaincode-go/pkg/cid"
"github.com/hyperledger/fabric-chaincode-go/shim"
	pb "github.com/hyperledger/fabric-protos-go/peer"
)
// Invoke makes payment of X units from A to B
func (t *SimpleChaincode) Invoke(stub shim.ChaincodeStubInterface) pb.Response {
	Info.Println("########### example_cc Invoke ###########")

	function, args := stub.GetFunctionAndParameters()

// Getting attributes from an idemix credential
	ou, found, err := cid.GetAttributeValue(stub, "ou");
if err != nil {
return shim.Error("Failed to get attribute 'ou'")
}
if !found {
return shim.Error("attribute 'ou' not found")
}
if !strings.HasSuffix(ou, "department1") {
return shim.Error(fmt.Sprintf("Incorrect 'ou' returned, got '%s' expecting to end with 'department1'", ou))
}
	role, found, err := cid.GetAttributeValue(stub, "role");
if err != nil {
return shim.Error("Failed to get attribute 'role'")
}
if !found {
return shim.Error("attribute 'role' not found")
}
if role != "member" {
return shim.Error(fmt.Sprintf("Incorrect 'role' returned, got '%s' expecting 'member'", role))
}

if function == "delete" {
// Deletes an entity from its state
return t.delete(stub, args)
}

if function == "query" {
// queries an entity state
return t.query(stub, args)
}

if function == "move" {
// Deletes an entity from its state
return t.move(stub, args)
}

	Error.Printf("Unknown action, check the first argument, must be one of 'delete', 'query', or 'move'. But got: %v", args[0])
return shim.Error(fmt.Sprintf("Unknown action, check the first argument, must be one of 'delete', 'query', or 'move'. But got: %v", args[0]))
}