github.com/hellobchain/third_party@v0.0.0-20230331131523-deb0478a2e52/ldap.v2/compare.go (about)

     1  // Copyright 2014 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  //
     5  // File contains Compare functionality
     6  //
     7  // https://tools.ietf.org/html/rfc4511
     8  //
     9  // CompareRequest ::= [APPLICATION 14] SEQUENCE {
    10  //              entry           LDAPDN,
    11  //              ava             AttributeValueAssertion }
    12  //
    13  // AttributeValueAssertion ::= SEQUENCE {
    14  //              attributeDesc   AttributeDescription,
    15  //              assertionValue  AssertionValue }
    16  //
    17  // AttributeDescription ::= LDAPString
    18  //                         -- Constrained to <attributedescription>
    19  //                         -- [RFC4512]
    20  //
    21  // AttributeValue ::= OCTET STRING
    22  //
    23  
    24  package ldap
    25  
    26  import (
    27  	"errors"
    28  	"fmt"
    29  
    30  	"gopkg.in/asn1-ber.v1"
    31  )
    32  
    33  // Compare checks to see if the attribute of the dn matches value. Returns true if it does otherwise
    34  // false with any error that occurs if any.
    35  func (l *Conn) Compare(dn, attribute, value string) (bool, error) {
    36  	packet := ber.Encode(ber.ClassUniversal, ber.TypeConstructed, ber.TagSequence, nil, "LDAP Request")
    37  	packet.AppendChild(ber.NewInteger(ber.ClassUniversal, ber.TypePrimitive, ber.TagInteger, l.nextMessageID(), "MessageID"))
    38  
    39  	request := ber.Encode(ber.ClassApplication, ber.TypeConstructed, ApplicationCompareRequest, nil, "Compare Request")
    40  	request.AppendChild(ber.NewString(ber.ClassUniversal, ber.TypePrimitive, ber.TagOctetString, dn, "DN"))
    41  
    42  	ava := ber.Encode(ber.ClassUniversal, ber.TypeConstructed, ber.TagSequence, nil, "AttributeValueAssertion")
    43  	ava.AppendChild(ber.NewString(ber.ClassUniversal, ber.TypePrimitive, ber.TagOctetString, attribute, "AttributeDesc"))
    44  	ava.AppendChild(ber.Encode(ber.ClassUniversal, ber.TypeConstructed, ber.TagOctetString, value, "AssertionValue"))
    45  	request.AppendChild(ava)
    46  	packet.AppendChild(request)
    47  
    48  	l.Debug.PrintPacket(packet)
    49  
    50  	msgCtx, err := l.sendMessage(packet)
    51  	if err != nil {
    52  		return false, err
    53  	}
    54  	defer l.finishMessage(msgCtx)
    55  
    56  	l.Debug.Printf("%d: waiting for response", msgCtx.id)
    57  	packetResponse, ok := <-msgCtx.responses
    58  	if !ok {
    59  		return false, NewError(ErrorNetwork, errors.New("ldap: response channel closed"))
    60  	}
    61  	packet, err = packetResponse.ReadPacket()
    62  	l.Debug.Printf("%d: got response %p", msgCtx.id, packet)
    63  	if err != nil {
    64  		return false, err
    65  	}
    66  
    67  	if l.Debug {
    68  		if err := addLDAPDescriptions(packet); err != nil {
    69  			return false, err
    70  		}
    71  		ber.PrintPacket(packet)
    72  	}
    73  
    74  	if packet.Children[1].Tag == ApplicationCompareResponse {
    75  		resultCode, resultDescription := getLDAPResultCode(packet)
    76  		if resultCode == LDAPResultCompareTrue {
    77  			return true, nil
    78  		} else if resultCode == LDAPResultCompareFalse {
    79  			return false, nil
    80  		} else {
    81  			return false, NewError(resultCode, errors.New(resultDescription))
    82  		}
    83  	}
    84  	return false, fmt.Errorf("Unexpected Response: %d", packet.Children[1].Tag)
    85  }