diff --git a/msg.c b/msg.c
index 79fee6d..8fd2008 100644
--- a/msg.c
+++ b/msg.c
@@ -144,7 +144,7 @@ static void port_id_pre_send(struct PortIdentity *pid)
 	pid->portNumber = htons(pid->portNumber);
 }
 
-static int suffix_post_recv(uint8_t *ptr, int len)
+static int suffix_post_recv(uint8_t *ptr, int len, struct tlv_extra *last)
 {
 	int cnt;
 	struct TLV *tlv;
@@ -166,14 +166,14 @@ static int suffix_post_recv(uint8_t *ptr, int len)
 		}
 		len -= tlv->length;
 		ptr += tlv->length;
-		if (tlv_post_recv(tlv)) {
+		if (tlv_post_recv(tlv, len ? NULL : last)) {
 			return -1;
 		}
 	}
 	return cnt;
 }
 
-static void suffix_pre_send(uint8_t *ptr, int cnt)
+static void suffix_pre_send(uint8_t *ptr, int cnt, struct tlv_extra *last)
 {
 	int i;
 	struct TLV *tlv;
@@ -183,7 +183,7 @@ static void suffix_pre_send(uint8_t *ptr, int cnt)
 
 	for (i = 0; i < cnt; i++) {
 		tlv = (struct TLV *) ptr;
-		tlv_pre_send(tlv);
+		tlv_pre_send(tlv, i == cnt - 1 ? last : NULL);
 		ptr += sizeof(struct TLV) + tlv->length;
 		tlv->type = htons(tlv->type);
 		tlv->length = htons(tlv->length);
@@ -344,7 +344,7 @@ int msg_post_recv(struct ptp_message *m, int cnt)
 		return -1;
 	}
 
-	m->tlv_count = suffix_post_recv(suffix, cnt - pdulen);
+	m->tlv_count = suffix_post_recv(suffix, cnt - pdulen, &m->last_tlv);
 	if (m->tlv_count == -1) {
 		return -1;
 	}
@@ -401,7 +401,7 @@ int msg_pre_send(struct ptp_message *m)
 	default:
 		return -1;
 	}
-	suffix_pre_send(suffix, m->tlv_count);
+	suffix_pre_send(suffix, m->tlv_count, &m->last_tlv);
 	return 0;
 }
 
diff --git a/msg.h b/msg.h
index 2feb804..279f3e6 100644
--- a/msg.h
+++ b/msg.h
@@ -26,6 +26,7 @@
 
 #include "ddt.h"
 #include "transport.h"
+#include "tlv.h"
 
 #define PTP_VERSION 2
 
@@ -204,6 +205,12 @@ struct ptp_message {
 	 * Contains the number of TLVs in the suffix.
 	 */
 	int tlv_count;
+	/**
+	 * Used to hold the data of the last TLV in the message when
+	 * the layout of the TLV makes it difficult to access the data
+	 * directly from the message's buffer.
+	 */
+	struct tlv_extra last_tlv;
 };
 
 /**
diff --git a/tlv.c b/tlv.c
index d1093ee..5471d4b 100644
--- a/tlv.c
+++ b/tlv.c
@@ -21,6 +21,7 @@
 
 #include "port.h"
 #include "tlv.h"
+#include "msg.h"
 
 #define TLV_LENGTH_INVALID(tlv, type) \
 	(tlv->length < sizeof(struct type) - sizeof(struct TLV))
@@ -41,7 +42,8 @@ static void scaled_ns_h2n(ScaledNs *sns)
 	sns->fractional_nanoseconds = htons(sns->fractional_nanoseconds);
 }
 
-static int mgt_post_recv(struct management_tlv *m, uint16_t data_len)
+static int mgt_post_recv(struct management_tlv *m, uint16_t data_len,
+                         struct tlv_extra *extra)
 {
 	struct defaultDS *dds;
 	struct currentDS *cds;
@@ -49,6 +51,7 @@ static int mgt_post_recv(struct management_tlv *m, uint16_t data_len)
 	struct timePropertiesDS *tp;
 	struct portDS *p;
 	struct time_status_np *tsn;
+	int extra_len = 0;
 	switch (m->id) {
 	case DEFAULT_DATA_SET:
 		if (data_len != sizeof(struct defaultDS))
@@ -105,12 +108,18 @@ static int mgt_post_recv(struct management_tlv *m, uint16_t data_len)
 		tsn->gmPresent = ntohl(tsn->gmPresent);
 		break;
 	}
+	if (extra_len) {
+		if (extra_len % 2)
+			extra_len++;
+		if (extra_len + sizeof(m->id) != m->length)
+			goto bad_length;
+	}
 	return 0;
 bad_length:
 	return -1;
 }
 
-static void mgt_pre_send(struct management_tlv *m)
+static void mgt_pre_send(struct management_tlv *m, struct tlv_extra *extra)
 {
 	struct defaultDS *dds;
 	struct currentDS *cds;
@@ -209,12 +218,15 @@ static void org_pre_send(struct organization_tlv *org)
 	}
 }
 
-int tlv_post_recv(struct TLV *tlv)
+int tlv_post_recv(struct TLV *tlv, struct tlv_extra *extra)
 {
 	int result = 0;
 	struct management_tlv *mgt;
 	struct management_error_status *mes;
 	struct path_trace_tlv *ptt;
+	struct tlv_extra dummy_extra;
+	if (!extra)
+		extra = &dummy_extra;
 
 	switch (tlv->type) {
 	case TLV_MANAGEMENT:
@@ -223,7 +235,7 @@ int tlv_post_recv(struct TLV *tlv)
 		mgt = (struct management_tlv *) tlv;
 		mgt->id = ntohs(mgt->id);
 		if (tlv->length > sizeof(mgt->id))
-			result = mgt_post_recv(mgt, tlv->length - sizeof(mgt->id));
+			result = mgt_post_recv(mgt, tlv->length - sizeof(mgt->id), extra);
 		break;
 	case TLV_MANAGEMENT_ERROR_STATUS:
 		if (TLV_LENGTH_INVALID(tlv, management_error_status))
@@ -261,7 +273,7 @@ bad_length:
 	return -1;
 }
 
-void tlv_pre_send(struct TLV *tlv)
+void tlv_pre_send(struct TLV *tlv, struct tlv_extra *extra)
 {
 	struct management_tlv *mgt;
 	struct management_error_status *mes;
@@ -270,7 +282,7 @@ void tlv_pre_send(struct TLV *tlv)
 	case TLV_MANAGEMENT:
 		mgt = (struct management_tlv *) tlv;
 		if (tlv->length > sizeof(mgt->id))
-			mgt_pre_send(mgt);
+			mgt_pre_send(mgt, extra);
 		mgt->id = htons(mgt->id);
 		break;
 	case TLV_MANAGEMENT_ERROR_STATUS:
diff --git a/tlv.h b/tlv.h
index 8cce615..cfcab68 100644
--- a/tlv.h
+++ b/tlv.h
@@ -21,7 +21,6 @@
 #define HAVE_TLV_H
 
 #include "ddt.h"
-#include "msg.h"
 
 /* TLV types */
 #define TLV_MANAGEMENT					0x0001
@@ -177,17 +176,28 @@ struct time_status_np {
 	struct ClockIdentity gmIdentity;
 } PACKED;
 
+struct tlv_extra {
+	union {
+		/* Empty for now, but will contain structs for the
+		 * TLVs that use the tlv_extra support. */
+	};
+};
+
 /**
  * Converts recognized value sub-fields into host byte order.
  * @param tlv Pointer to a Type Length Value field.
+ * @param extra Additional struct where data from tlv will be saved,
+ * can be NULL.
  * @return Zero if successful, otherwise non-zero
  */
-int tlv_post_recv(struct TLV *tlv);
+int tlv_post_recv(struct TLV *tlv, struct tlv_extra *extra);
 
 /**
  * Converts recognized value sub-fields into network byte order.
  * @param tlv Pointer to a Type Length Value field.
+ * @param extra Additional struct containing tlv data to send, can be
+ * NULL.
  */
-void tlv_pre_send(struct TLV *tlv);
+void tlv_pre_send(struct TLV *tlv, struct tlv_extra *extra);
 
 #endif