2 files changed, 23 insertions, 2 deletions
diff --git a/src/core/message.c b/src/core/message.c
index 5fdad109..64a63201 100644
--- a/src/core/message.c
+++ b/src/core/message.c
@@ -29,6 +29,7 @@ struct nng_msg {
 	nni_chunk      m_body;
 	uint32_t       m_pipe; // set on receive
 	nni_atomic_int m_refcnt;
+	nng_sockaddr   m_addr; // set on receive, transport use
 };
 
 #if 0
@@ -656,3 +657,15 @@ nni_msg_get_pipe(const nni_msg *m)
 {
 	return (m->m_pipe);
 }
+
+const nng_sockaddr *
+nni_msg_address(const nni_msg *msg)
+{
+	return (&msg->m_addr);
+}
+
+void
+nni_msg_set_address(nng_msg *msg, const nng_sockaddr *addr)
+{
+	msg->m_addr = *addr;
+}
diff --git a/src/core/message.h b/src/core/message.h
index 7e35ba75..9f88cbe8 100644
--- a/src/core/message.h
+++ b/src/core/message.h
@@ -20,9 +20,9 @@ extern int      nni_msg_realloc(nni_msg *, size_t);
 extern int      nni_msg_reserve(nni_msg *, size_t);
 extern size_t   nni_msg_capacity(nni_msg *);
 extern int      nni_msg_dup(nni_msg **, const nni_msg *);
-extern void *   nni_msg_header(nni_msg *);
+extern void    *nni_msg_header(nni_msg *);
 extern size_t   nni_msg_header_len(const nni_msg *);
-extern void *   nni_msg_body(nni_msg *);
+extern void    *nni_msg_body(nni_msg *);
 extern size_t   nni_msg_len(const nni_msg *);
 extern int      nni_msg_append(nni_msg *, const void *, size_t);
 extern int      nni_msg_insert(nni_msg *, const void *, size_t);
@@ -55,6 +55,14 @@ extern void     nni_msg_clone(nni_msg *);
 extern nni_msg *nni_msg_unique(nni_msg *);
 extern bool     nni_msg_shared(nni_msg *);
 
+// Socket address access. Principally useful for transports like UDP,
+// which may need to remember or add the socket address later.
+// SP transports will generally not support upper layers setting the
+// address on send, but will take the information from the pipe.
+// It may be set on receive, depending upon the transport.
+extern const nng_sockaddr *nni_msg_address(const nni_msg *);
+extern void nni_msg_set_address(nng_msg *, const nng_sockaddr *);
+
 // nni_msg_pull_up ensures that the message is unique, and that any
 // header present is "pulled up" into the message body.  If the function
 // cannot do this for any reason (out of space in the body), then NULL