lib/tsocket: add tdgram_inet_udp_broadcast_socket()

This is similar to tdgram_inet_udp_socket(), but it allows
the use of ipv4 broadcast traffic.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=11316

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

2 files changed, 59 insertions, 0 deletions

diff --git a/lib/tsocket/tsocket.h b/lib/tsocket/tsocket.h
index 296c7c555ae..f52b7466dfb 100644
--- a/lib/tsocket/tsocket.h
+++ b/lib/tsocket/tsocket.h
@@ -705,6 +705,8 @@ bool tdgram_bsd_optimize_recvfrom(struct tdgram_context *dgram,
  *                      communication. The function will allocate the memory.
  *
  * @return              0 on success, -1 on error with errno set.
+ *
+ * @see tdgram_inet_udp_broadcast_socket()
  */
 int tdgram_inet_udp_socket(const struct tsocket_address *local,
 			    const struct tsocket_address *remote,
@@ -722,6 +724,33 @@ int _tdgram_inet_udp_socket(const struct tsocket_address *local,
 
 #ifdef DOXYGEN
 /**
+ * @brief Create a tdgram_context for a ipv4 UDP broadcast (and unicast) communication.
+ *
+ * @param[in]  local    An 'inet' (ipv4 only) tsocket_address for the local endpoint.
+ *
+ * @param[in]  mem_ctx  The talloc memory context to use.
+ *
+ * @param[in]  dgram    The tdgram_context pointer to setup the udp
+ *                      communication. The function will allocate the memory.
+ *
+ * @return              0 on success, -1 on error with errno set.
+ *
+ * @see tdgram_inet_udp_socket()
+ */
+int tdgram_inet_udp_broadcast_socket(const struct tsocket_address *local,
+				     TALLOC_CTX *mem_ctx,
+				     struct tdgram_context **dgram);
+#else
+int _tdgram_inet_udp_broadcast_socket(const struct tsocket_address *local,
+				      TALLOC_CTX *mem_ctx,
+				      struct tdgram_context **dgram,
+				      const char *location);
+#define tdgram_inet_udp_broadcast_socket(local, mem_ctx, dgram) \
+	_tdgram_inet_udp_broadcast_socket(local, mem_ctx, dgram, __location__)
+#endif
+
+#ifdef DOXYGEN
+/**
  * @brief Create a tdgram_context for unix domain datagram communication.
  *
  * @param[in]  local    An 'unix' tsocket_address for the local endpoint.
diff --git a/lib/tsocket/tsocket_bsd.c b/lib/tsocket/tsocket_bsd.c
index 9ddbc061b94..f1ece7595e0 100644
--- a/lib/tsocket/tsocket_bsd.c
+++ b/lib/tsocket/tsocket_bsd.c
@@ -1441,6 +1441,36 @@ int _tdgram_inet_udp_socket(const struct tsocket_address *local,
 	return ret;
 }
 
+int _tdgram_inet_udp_broadcast_socket(const struct tsocket_address *local,
+				      TALLOC_CTX *mem_ctx,
+				      struct tdgram_context **dgram,
+				      const char *location)
+{
+	struct tsocket_address_bsd *lbsda =
+		talloc_get_type_abort(local->private_data,
+		struct tsocket_address_bsd);
+	int ret;
+
+	switch (lbsda->u.sa.sa_family) {
+	case AF_INET:
+		break;
+#ifdef HAVE_IPV6
+	case AF_INET6:
+		/* only ipv4 */
+		errno = EINVAL;
+		return -1;
+#endif
+	default:
+		errno = EINVAL;
+		return -1;
+	}
+
+	ret = tdgram_bsd_dgram_socket(local, NULL, true,
+				      mem_ctx, dgram, location);
+
+	return ret;
+}
+
 int _tdgram_unix_socket(const struct tsocket_address *local,
 			const struct tsocket_address *remote,
 			TALLOC_CTX *mem_ctx,