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-rw-r--r--source4/lib/messaging/config.m41
-rw-r--r--source4/lib/messaging/config.mk8
-rw-r--r--source4/lib/messaging/messaging.c445
3 files changed, 454 insertions, 0 deletions
diff --git a/source4/lib/messaging/config.m4 b/source4/lib/messaging/config.m4
new file mode 100644
index 0000000000..1797069ff2
--- /dev/null
+++ b/source4/lib/messaging/config.m4
@@ -0,0 +1 @@
+SMB_SUBSYSTEM_MK(MESSAGING,lib/messaging/config.mk)
diff --git a/source4/lib/messaging/config.mk b/source4/lib/messaging/config.mk
new file mode 100644
index 0000000000..6c30894779
--- /dev/null
+++ b/source4/lib/messaging/config.mk
@@ -0,0 +1,8 @@
+
+################################################
+# Start SUBSYSTEM MESSAGING
+[SUBSYSTEM::MESSAGING]
+INIT_OBJ_FILES = \
+ lib/messaging/messaging.o
+# End SUBSYSTEM MESSAGING
+################################################
diff --git a/source4/lib/messaging/messaging.c b/source4/lib/messaging/messaging.c
new file mode 100644
index 0000000000..f9caf5071c
--- /dev/null
+++ b/source4/lib/messaging/messaging.c
@@ -0,0 +1,445 @@
+/*
+ Unix SMB/CIFS implementation.
+
+ Samba internal messaging functions
+
+ Copyright (C) Andrew Tridgell 2004
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+/* change the message version with any incompatible changes in the protocol */
+#define MESSAGING_VERSION 1
+
+struct messaging_state {
+ servid_t server_id;
+ struct socket_context *sock;
+ char *path;
+ struct dispatch_fn *dispatch;
+
+ struct {
+ struct event_context *ev;
+ struct fd_event *fde;
+ } event;
+};
+
+/* we have a linked list of dispatch handlers that this messaging
+ server can deal with */
+struct dispatch_fn {
+ struct dispatch_fn *next, *prev;
+ uint32_t msg_type;
+ void *private;
+ void (*fn)(void *msg_ctx, void *private,
+ uint32_t msg_type, servid_t server_id, DATA_BLOB *data);
+};
+
+/* an individual message */
+struct messaging_rec {
+ struct messaging_rec *next, *prev;
+
+ struct messaging_state *msg;
+ struct socket_context *sock;
+ struct fd_event *fde;
+ const char *path;
+
+ struct {
+ uint32_t version;
+ uint32_t msg_type;
+ servid_t from;
+ servid_t to;
+ uint32_t length;
+ } header;
+
+ DATA_BLOB data;
+
+ uint32_t ndone;
+};
+
+/*
+ A useful function for testing the message system.
+*/
+static void ping_message(void *msg_ctx, void *private,
+ uint32_t msg_type, servid_t src, DATA_BLOB *data)
+{
+ DEBUG(1,("INFO: Received PING message from server %u [%.*s]\n",
+ (uint_t)src, data->length, data->data?(const char *)data->data:""));
+ messaging_send(msg_ctx, src, MSG_PONG, data);
+}
+
+/*
+ return the path to a messaging socket
+*/
+static char *messaging_path(TALLOC_CTX *mem_ctx, servid_t server_id)
+{
+ char *name = talloc_asprintf(mem_ctx, "messaging/msg.%u", (unsigned)server_id);
+ char *ret;
+ ret = lock_path(mem_ctx, name);
+ talloc_free(name);
+ return ret;
+}
+
+/*
+ dispatch a fully received message
+*/
+static void messaging_dispatch(struct messaging_state *msg, struct messaging_rec *rec)
+{
+ struct dispatch_fn *d;
+ for (d=msg->dispatch;d;d=d->next) {
+ if (d->msg_type == rec->header.msg_type) {
+ d->fn(msg, d->private, d->msg_type, rec->header.from, &rec->data);
+ }
+ }
+
+ /* we don't free the record itself here as there may
+ be more messages from this client */
+ data_blob_free(&rec->data);
+ rec->header.length = 0;
+ rec->ndone = 0;
+}
+
+
+/*
+ handle IO for a single message
+*/
+static void messaging_recv_handler(struct event_context *ev, struct fd_event *fde,
+ time_t t, uint16_t flags)
+{
+ struct messaging_rec *rec = fde->private;
+ struct messaging_state *msg = rec->msg;
+ NTSTATUS status;
+
+ if (rec->ndone < sizeof(rec->header)) {
+ /* receive the header */
+ DATA_BLOB blob;
+ status = socket_recv(rec->sock, rec,
+ &blob, sizeof(rec->header) - rec->ndone, 0);
+ if (NT_STATUS_IS_ERR(status)) {
+ talloc_free(rec);
+ return;
+ }
+
+ if (blob.length == 0) {
+ return;
+ }
+
+ memcpy(rec->ndone + (char *)&rec->header, blob.data, blob.length);
+ rec->ndone += blob.length;
+ data_blob_free(&blob);
+
+ if (rec->ndone == sizeof(rec->header)) {
+ if (rec->header.version != MESSAGING_VERSION) {
+ DEBUG(0,("meessage with wrong version %u\n",
+ rec->header.version));
+ talloc_free(rec);
+ }
+ rec->data = data_blob_talloc(rec, NULL, rec->header.length);
+ if (rec->data.length != rec->header.length) {
+ DEBUG(0,("Unable to allocate message of size %u\n",
+ rec->header.length));
+ talloc_free(rec);
+ }
+ }
+ }
+
+ if (rec->ndone >= sizeof(rec->header) &&
+ rec->ndone < sizeof(rec->header) + rec->header.length) {
+ /* receive the body, if any */
+ DATA_BLOB blob;
+ status = socket_recv(rec->sock, rec,
+ &blob, sizeof(rec->header) + rec->header.length - rec->ndone, 0);
+ if (NT_STATUS_IS_ERR(status)) {
+ talloc_free(rec);
+ return;
+ }
+
+ if (blob.length == 0) {
+ return;
+ }
+
+ memcpy(rec->data.data + (rec->ndone - sizeof(rec->header)),
+ blob.data, blob.length);
+
+ rec->ndone += blob.length;
+ }
+
+ if (rec->ndone == sizeof(rec->header) + rec->header.length) {
+ /* we've got the whole message */
+ messaging_dispatch(msg, rec);
+ }
+}
+
+/*
+ destroy a messaging record
+*/
+static int rec_destructor(void *ptr)
+{
+ struct messaging_rec *rec = ptr;
+ struct messaging_state *msg = rec->msg;
+ event_remove_fd(msg->event.ev, rec->fde);
+ return 0;
+}
+
+/*
+ handle a new incoming connection
+*/
+static void messaging_listen_handler(struct event_context *ev, struct fd_event *fde,
+ time_t t, uint16_t flags)
+{
+ struct messaging_state *msg = fde->private;
+ struct messaging_rec *rec;
+ NTSTATUS status;
+ struct fd_event fde2;
+
+ rec = talloc_p(msg, struct messaging_rec);
+ if (rec == NULL) {
+ smb_panic("Unable to allocate messaging_rec");
+ }
+
+ status = socket_accept(msg->sock, &rec->sock, 0);
+ if (!NT_STATUS_IS_OK(status)) {
+ smb_panic("Unable to accept messaging_rec");
+ }
+ talloc_steal(rec, rec->sock);
+
+ rec->msg = msg;
+ rec->ndone = 0;
+ rec->header.length = 0;
+ rec->path = msg->path;
+
+ fde2.private = rec;
+ fde2.fd = socket_get_fd(rec->sock);
+ fde2.flags = EVENT_FD_READ;
+ fde2.handler = messaging_recv_handler;
+
+ rec->fde = event_add_fd(msg->event.ev, &fde2);
+
+ talloc_set_destructor(rec, rec_destructor);
+}
+
+/*
+ Register a dispatch function for a particular message type.
+*/
+void messaging_register(void *ctx, void *private,
+ uint32_t msg_type,
+ void (*fn)(void *, void *, uint32_t, servid_t, DATA_BLOB *))
+{
+ struct messaging_state *msg = ctx;
+ struct dispatch_fn *d;
+
+ d = talloc_p(msg, struct dispatch_fn);
+ d->msg_type = msg_type;
+ d->private = private;
+ d->fn = fn;
+ DLIST_ADD(msg->dispatch, d);
+}
+
+/*
+ De-register the function for a particular message type.
+*/
+void messaging_deregister(void *ctx, uint32_t msg_type)
+{
+ struct messaging_state *msg = ctx;
+ struct dispatch_fn *d, *next;
+
+ for (d = msg->dispatch; d; d = next) {
+ next = d->next;
+ if (d->msg_type == msg_type) {
+ DLIST_REMOVE(msg->dispatch, d);
+ talloc_free(d);
+ }
+ }
+}
+
+
+
+/*
+ handle IO for sending a message
+*/
+static void messaging_send_handler(struct event_context *ev, struct fd_event *fde,
+ time_t t, uint16_t flags)
+{
+ struct messaging_rec *rec = fde->private;
+ NTSTATUS status;
+
+ if (rec->ndone < sizeof(rec->header)) {
+ /* send the header */
+ size_t nsent;
+ DATA_BLOB blob;
+
+ blob.data = rec->ndone + (char *)&rec->header;
+ blob.length = sizeof(rec->header) - rec->ndone;
+
+ status = socket_send(rec->sock, rec, &blob, &nsent, 0);
+ if (NT_STATUS_IS_ERR(status)) {
+ talloc_free(rec);
+ return;
+ }
+
+ if (nsent == 0) {
+ return;
+ }
+
+ rec->ndone += nsent;
+ }
+
+ if (rec->ndone >= sizeof(rec->header) &&
+ rec->ndone < sizeof(rec->header) + rec->header.length) {
+ /* send the body, if any */
+ DATA_BLOB blob;
+ size_t nsent;
+
+ blob.data = rec->data.data + (rec->ndone - sizeof(rec->header));
+ blob.length = rec->header.length - (rec->ndone - sizeof(rec->header));
+
+ status = socket_send(rec->sock, rec, &blob, &nsent, 0);
+ if (NT_STATUS_IS_ERR(status)) {
+ talloc_free(rec);
+ return;
+ }
+
+ rec->ndone += nsent;
+ }
+
+ if (rec->ndone == sizeof(rec->header) + rec->header.length) {
+ /* we've done the whole message */
+ talloc_free(rec);
+ }
+}
+
+
+/*
+ Send a message to a particular server
+*/
+NTSTATUS messaging_send(void *msg_ctx, servid_t server, uint32_t msg_type, DATA_BLOB *data)
+{
+ struct messaging_state *msg = msg_ctx;
+ struct messaging_rec *rec;
+ NTSTATUS status;
+ struct fd_event fde;
+
+ rec = talloc_p(msg, struct messaging_rec);
+ if (rec == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ rec->msg = msg;
+ rec->header.version = MESSAGING_VERSION;
+ rec->header.msg_type = msg_type;
+ rec->header.from = msg->server_id;
+ rec->header.to = server;
+ rec->header.length = data?data->length:0;
+ if (rec->header.length != 0) {
+ rec->data = data_blob_talloc(rec, data->data, data->length);
+ } else {
+ rec->data = data_blob(NULL, 0);
+ }
+ rec->ndone = 0;
+
+ status = socket_create("unix", SOCKET_TYPE_STREAM, &rec->sock, 0);
+ if (!NT_STATUS_IS_OK(status)) {
+ talloc_free(rec);
+ return status;
+ }
+ talloc_steal(rec, rec->sock);
+
+ rec->path = messaging_path(rec, server);
+
+ status = socket_connect(rec->sock, NULL, 0, rec->path, 0, 0);
+ if (!NT_STATUS_IS_OK(status)) {
+ talloc_free(rec);
+ return status;
+ }
+
+ fde.private = rec;
+ fde.fd = socket_get_fd(rec->sock);
+ fde.flags = EVENT_FD_WRITE;
+ fde.handler = messaging_send_handler;
+
+ rec->fde = event_add_fd(msg->event.ev, &fde);
+
+ talloc_set_destructor(rec, rec_destructor);
+
+ return NT_STATUS_OK;
+}
+
+
+/*
+ destroy the messaging context
+*/
+static int messaging_destructor(void *msg_ctx)
+{
+ struct messaging_state *msg = msg_ctx;
+ event_remove_fd(msg->event.ev, msg->event.fde);
+ return 0;
+}
+
+/*
+ create the listening socket and setup the dispatcher
+*/
+void *messaging_init(TALLOC_CTX *mem_ctx, servid_t server_id, struct event_context *ev)
+{
+ struct messaging_state *msg;
+ NTSTATUS status;
+ struct fd_event fde;
+
+ msg = talloc_p(mem_ctx, struct messaging_state);
+ if (msg == NULL) {
+ return NULL;
+ }
+
+ /* create the messaging directory if needed */
+ msg->path = lock_path(msg, "messaging");
+ mkdir(msg->path, 0700);
+ talloc_free(msg->path);
+
+ msg->server_id = server_id;
+ msg->dispatch = NULL;
+ msg->path = messaging_path(msg, server_id);
+
+ status = socket_create("unix", SOCKET_TYPE_STREAM, &msg->sock, 0);
+ if (!NT_STATUS_IS_OK(status)) {
+ talloc_free(msg);
+ return NULL;
+ }
+
+ /* by stealing here we ensure that the socket is cleaned up (and even
+ deleted) on exit */
+ talloc_steal(msg, msg->sock);
+
+ status = socket_listen(msg->sock, msg->path, 0, 50, 0);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0,("Unable to setup messaging listener for '%s'\n", msg->path));
+ talloc_free(msg);
+ return NULL;
+ }
+
+ fde.private = msg;
+ fde.fd = socket_get_fd(msg->sock);
+ fde.flags = EVENT_FD_READ;
+ fde.handler = messaging_listen_handler;
+
+ msg->event.ev = ev;
+ msg->event.fde = event_add_fd(ev, &fde);
+
+ talloc_set_destructor(msg, messaging_destructor);
+
+ messaging_register(msg, NULL, MSG_PING, ping_message);
+
+ return msg;
+}
+
+