lib: Push down unique generation one level

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>

source3/lib/messages.c

@@ -303,7 +303,6 @@ struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
 	ctx->id = (struct server_id) {
 		.pid = getpid(), .vnn = NONCLUSTER_VNN
 	};
-	ctx->id.unique_id = serverid_get_random_unique_id();
 
 	ctx->event_ctx = ev;
 
@@ -340,7 +339,7 @@ struct messaging_context *messaging_init(TALLOC_CTX *mem_ctx,
 	}
 
 	ctx->msg_dgm_ref = messaging_dgm_ref(
-		ctx, ctx->event_ctx, ctx->id.unique_id,
+		ctx, ctx->event_ctx, &ctx->id.unique_id,
 		priv_path, lck_path, messaging_recv_cb, ctx, &ret);
 
 	if (ctx->msg_dgm_ref == NULL) {
@@ -400,10 +399,9 @@ NTSTATUS messaging_reinit(struct messaging_context *msg_ctx)
 	msg_ctx->id = (struct server_id) {
 		.pid = getpid(), .vnn = msg_ctx->id.vnn
 	};
-	msg_ctx->id.unique_id = serverid_get_random_unique_id();
 
 	msg_ctx->msg_dgm_ref = messaging_dgm_ref(
-		msg_ctx, msg_ctx->event_ctx, msg_ctx->id.unique_id,
+		msg_ctx, msg_ctx->event_ctx, &msg_ctx->id.unique_id,
 		private_path("msg.sock"), lock_path("msg.lock"),
 		messaging_recv_cb, msg_ctx, &ret);
 

source3/lib/messages_dgm.c

@@ -29,6 +29,7 @@
 #include "lib/param/param.h"
 #include "poll_funcs/poll_funcs_tevent.h"
 #include "unix_msg/unix_msg.h"
+#include "lib/util/genrand.h"
 
 struct sun_path_buf {
 	/*
@@ -67,12 +68,13 @@ static int messaging_dgm_context_destructor(struct messaging_dgm_context *c);
 
 static int messaging_dgm_lockfile_create(struct messaging_dgm_context *ctx,
 					 pid_t pid, int *plockfile_fd,
-					 uint64_t unique)
+					 uint64_t *punique)
 {
 	char buf[64];
 	int lockfile_fd;
 	struct sun_path_buf lockfile_name;
 	struct flock lck;
+	uint64_t unique;
 	int unique_len, ret;
 	ssize_t written;
 
@@ -104,6 +106,19 @@ static int messaging_dgm_lockfile_create(struct messaging_dgm_context *ctx,
 		goto fail_close;
 	}
 
+	/*
+	 * Directly using the binary value for
+	 * SERVERID_UNIQUE_ID_NOT_TO_VERIFY is a layering
+	 * violation. But including all of ndr here just for this
+	 * seems to be a bit overkill to me. Also, messages_dgm might
+	 * be replaced sooner or later by something streams-based,
+	 * where unique_id generation will be handled differently.
+	 */
+
+	do {
+		generate_random_buffer((uint8_t *)&unique, sizeof(unique));
+	} while (unique == UINT64_C(0xFFFFFFFFFFFFFFFF));
+
 	unique_len = snprintf(buf, sizeof(buf), "%ju\n", (uintmax_t)unique);
 
 	/* shorten a potentially preexisting file */
@@ -124,6 +139,7 @@ static int messaging_dgm_lockfile_create(struct messaging_dgm_context *ctx,
 	}
 
 	*plockfile_fd = lockfile_fd;
+	*punique = unique;
 	return 0;
 
 fail_unlink:
@@ -134,7 +150,7 @@ fail_close:
 }
 
 int messaging_dgm_init(struct tevent_context *ev,
-		       uint64_t unique,
+		       uint64_t *punique,
 		       const char *socket_dir,
 		       const char *lockfile_dir,
 		       void (*recv_cb)(const uint8_t *msg,
@@ -186,7 +202,7 @@ int messaging_dgm_init(struct tevent_context *ev,
 	}
 
 	ret = messaging_dgm_lockfile_create(ctx, ctx->pid, &ctx->lockfile_fd,
-					    unique);
+					    punique);
 	if (ret != 0) {
 		DEBUG(1, ("%s: messaging_dgm_create_lockfile failed: %s\n",
 			  __func__, strerror(ret)));

source3/lib/messages_dgm.h

@@ -25,7 +25,7 @@
 #include <tevent.h>
 
 int messaging_dgm_init(struct tevent_context *ev,
-		       uint64_t unique,
+		       uint64_t *unique,
 		       const char *socket_dir,
 		       const char *lockfile_dir,
 		       void (*recv_cb)(const uint8_t *msg,

source3/lib/messages_dgm_ref.c

@@ -40,7 +40,7 @@ static void msg_dgm_ref_recv(const uint8_t *msg, size_t msg_len,
 			     int *fds, size_t num_fds, void *private_data);
 
 void *messaging_dgm_ref(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
-			uint64_t unique,
+			uint64_t *unique,
 			const char *socket_dir,
 			const char *lockfile_dir,
 			void (*recv_cb)(const uint8_t *msg, size_t msg_len,
@@ -82,6 +82,14 @@ void *messaging_dgm_ref(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
 		}
 		dgm_pid = getpid();
 	} else {
+		int ret;
+		ret = messaging_dgm_get_unique(getpid(), unique);
+		if (ret != 0) {
+			TALLOC_FREE(result);
+			*err = ret;
+			return NULL;
+		}
+
 		result->tevent_handle = messaging_dgm_register_tevent_context(
 			result, ev);
 		if (result->tevent_handle == NULL) {

source3/lib/messages_dgm_ref.h

@@ -25,7 +25,7 @@
 #include "replace.h"
 
 void *messaging_dgm_ref(TALLOC_CTX *mem_ctx, struct tevent_context *ev,
-			uint64_t unique,
+			uint64_t *unique,
 			const char *socket_dir,
 			const char *lockfile_dir,
 			void (*recv_cb)(const uint8_t *msg, size_t msg_len,

source3/wscript_build

@@ -299,7 +299,8 @@ bld.SAMBA3_SUBSYSTEM('TDB_LIB',
 
 bld.SAMBA3_LIBRARY('messages_dgm',
                    source='''lib/messages_dgm.c lib/messages_dgm_ref.c''',
-                   deps='talloc UNIX_MSG POLL_FUNCS_TEVENT samba-debug',
+                   deps='''talloc UNIX_MSG POLL_FUNCS_TEVENT samba-debug
+                           genrand''',
                    private_library=True)
 
 bld.SAMBA3_LIBRARY('messages_util',

source4/lib/messaging/messaging.c

@@ -342,7 +342,7 @@ struct imessaging_context *imessaging_init(TALLOC_CTX *mem_ctx,
 	}
 
 	msg->msg_dgm_ref = messaging_dgm_ref(
-		msg, ev, server_id.unique_id, msg->sock_dir, msg->lock_dir,
+		msg, ev, &server_id.unique_id, msg->sock_dir, msg->lock_dir,
 		imessaging_dgm_recv, msg, &ret);
 
 	if (msg->msg_dgm_ref == NULL) {