Merge pull request #98 from liggitt/dn-comparison

Ignore unescaped leading/trailing spaces in RDN type/value

Author: liggitt

.travis.yml

@@ -1,8 +1,8 @@
 language: go
 env:
     global:
-        - VET_VERSIONS="1.5 1.6 1.7 tip"
-        - LINT_VERSIONS="1.5 1.6 1.7 tip"
+        - VET_VERSIONS="1.6 1.7 tip"
+        - LINT_VERSIONS="1.6 1.7 tip"
 go:
     - 1.2
     - 1.3

dn.go

@@ -83,9 +83,19 @@ func ParseDN(str string) (*DN, error) {
 	attribute := new(AttributeTypeAndValue)
 	escaping := false
 
+	unescapedTrailingSpaces := 0
+	stringFromBuffer := func() string {
+		s := buffer.String()
+		s = s[0 : len(s)-unescapedTrailingSpaces]
+		buffer.Reset()
+		unescapedTrailingSpaces = 0
+		return s
+	}
+
 	for i := 0; i < len(str); i++ {
 		char := str[i]
 		if escaping {
+			unescapedTrailingSpaces = 0
 			escaping = false
 			switch char {
 			case ' ', '"', '#', '+', ',', ';', '<', '=', '>', '\\':
@@ -107,10 +117,10 @@ func ParseDN(str string) (*DN, error) {
 			buffer.WriteByte(dst[0])
 			i++
 		} else if char == '\\' {
+			unescapedTrailingSpaces = 0
 			escaping = true
 		} else if char == '=' {
-			attribute.Type = buffer.String()
-			buffer.Reset()
+			attribute.Type = stringFromBuffer()
 			// Special case: If the first character in the value is # the
 			// following data is BER encoded so we can just fast forward
 			// and decode.
@@ -133,24 +143,33 @@ func ParseDN(str string) (*DN, error) {
 			}
 		} else if char == ',' || char == '+' {
 			// We're done with this RDN or value, push it
-			attribute.Value = buffer.String()
+			attribute.Value = stringFromBuffer()
 			rdn.Attributes = append(rdn.Attributes, attribute)
 			attribute = new(AttributeTypeAndValue)
 			if char == ',' {
 				dn.RDNs = append(dn.RDNs, rdn)
 				rdn = new(RelativeDN)
 				rdn.Attributes = make([]*AttributeTypeAndValue, 0)
 			}
-			buffer.Reset()
+		} else if char == ' ' && buffer.Len() == 0 {
+			// ignore unescaped leading spaces
+			continue
 		} else {
+			if char == ' ' {
+				// Track unescaped spaces in case they are trailing and we need to remove them
+				unescapedTrailingSpaces++
+			} else {
+				// Reset if we see a non-space char
+				unescapedTrailingSpaces = 0
+			}
 			buffer.WriteByte(char)
 		}
 	}
 	if buffer.Len() > 0 {
 		if len(attribute.Type) == 0 {
 			return nil, errors.New("DN ended with incomplete type, value pair")
 		}
-		attribute.Value = buffer.String()
+		attribute.Value = stringFromBuffer()
 		rdn.Attributes = append(rdn.Attributes, attribute)
 		dn.RDNs = append(dn.RDNs, rdn)
 	}

dn_test.go

@@ -31,6 +31,22 @@ func TestSuccessfulDNParsing(t *testing.T) {
 			&ldap.RelativeDN{[]*ldap.AttributeTypeAndValue{&ldap.AttributeTypeAndValue{"DC", "net"}}}}},
 		"CN=Lu\\C4\\8Di\\C4\\87": ldap.DN{[]*ldap.RelativeDN{
 			&ldap.RelativeDN{[]*ldap.AttributeTypeAndValue{&ldap.AttributeTypeAndValue{"CN", "Lučić"}}}}},
+		"  CN  =  Lu\\C4\\8Di\\C4\\87  ": ldap.DN{[]*ldap.RelativeDN{
+			&ldap.RelativeDN{[]*ldap.AttributeTypeAndValue{&ldap.AttributeTypeAndValue{"CN", "Lučić"}}}}},
+		`   A   =   1   ,   B   =   2   `: ldap.DN{[]*ldap.RelativeDN{
+			&ldap.RelativeDN{[]*ldap.AttributeTypeAndValue{&ldap.AttributeTypeAndValue{"A", "1"}}},
+			&ldap.RelativeDN{[]*ldap.AttributeTypeAndValue{&ldap.AttributeTypeAndValue{"B", "2"}}}}},
+		`   A   =   1   +   B   =   2   `: ldap.DN{[]*ldap.RelativeDN{
+			&ldap.RelativeDN{[]*ldap.AttributeTypeAndValue{
+				&ldap.AttributeTypeAndValue{"A", "1"},
+				&ldap.AttributeTypeAndValue{"B", "2"}}}}},
+		`   \ \ A\ \    =   \ \ 1\ \    ,   \ \ B\ \    =   \ \ 2\ \    `: ldap.DN{[]*ldap.RelativeDN{
+			&ldap.RelativeDN{[]*ldap.AttributeTypeAndValue{&ldap.AttributeTypeAndValue{"  A  ", "  1  "}}},
+			&ldap.RelativeDN{[]*ldap.AttributeTypeAndValue{&ldap.AttributeTypeAndValue{"  B  ", "  2  "}}}}},
+		`   \ \ A\ \    =   \ \ 1\ \    +   \ \ B\ \    =   \ \ 2\ \    `: ldap.DN{[]*ldap.RelativeDN{
+			&ldap.RelativeDN{[]*ldap.AttributeTypeAndValue{
+				&ldap.AttributeTypeAndValue{"  A  ", "  1  "},
+				&ldap.AttributeTypeAndValue{"  B  ", "  2  "}}}}},
 	}
 
 	for test, answer := range testcases {
@@ -41,6 +57,13 @@ func TestSuccessfulDNParsing(t *testing.T) {
 		}
 		if !reflect.DeepEqual(dn, &answer) {
 			t.Errorf("Parsed DN %s is not equal to the expected structure", test)
+			t.Logf("Expected:")
+			for _, rdn := range answer.RDNs {
+				for _, attribs := range rdn.Attributes {
+					t.Logf("#%v\n", attribs)
+				}
+			}
+			t.Logf("Actual:")
 			for _, rdn := range dn.RDNs {
 				for _, attribs := range rdn.Attributes {
 					t.Logf("#%v\n", attribs)