1 files changed, 55 insertions, 0 deletions
diff --git a/dhcpv4/option_domain_search.go b/dhcpv4/option_domain_search.go
new file mode 100644
index 0000000..c30cbe1
--- /dev/null
+++ b/dhcpv4/option_domain_search.go
@@ -0,0 +1,55 @@
+package dhcpv4
+
+// This module defines the OptDomainSearch structure.
+// https://tools.ietf.org/html/rfc3397
+
+import (
+	"fmt"
+)
+
+// OptDomainSearch represents an option encapsulating a domain search list.
+type OptDomainSearch struct {
+	DomainSearch []string
+}
+
+func (op *OptDomainSearch) Code() OptionCode {
+	return OptionDNSDomainSearchList
+}
+
+func (op *OptDomainSearch) ToBytes() []byte {
+	buf := []byte{byte(op.Code()), byte(op.Length())}
+	buf = append(buf, LabelsToBytes(op.DomainSearch)...)
+	return buf
+}
+
+func (op *OptDomainSearch) Length() int {
+	var length int
+	for _, label := range op.DomainSearch {
+		length += len(label) + 2 // add the first and the last length bytes
+	}
+	return length
+}
+
+func (op *OptDomainSearch) String() string {
+	return fmt.Sprintf("DNS Domain Search List ->", op.DomainSearch)
+}
+
+// build an OptDomainSearch structure from a sequence of bytes.
+func ParseOptDomainSearch(data []byte) (*OptDomainSearch, error) {
+	if len(data) < 2 {
+		return nil, ErrShortByteStream
+	}
+	code := OptionCode(data[0])
+	if code != OptionDNSDomainSearchList {
+		return nil, fmt.Errorf("expected code %v, got %v", OptionDNSDomainSearchList, code)
+	}
+	length := int(data[1])
+	if len(data) < 2+length {
+		return nil, ErrShortByteStream
+	}
+	domainSearch, err := LabelsFromBytes(data[2:length+2])
+	if err != nil {
+		return nil, err
+	}
+	return &OptDomainSearch{DomainSearch: domainSearch}, nil
+}