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path: root/drivers/scsi/scsi_netlink.c
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Diffstat (limited to 'drivers/scsi/scsi_netlink.c')
-rw-r--r--drivers/scsi/scsi_netlink.c199
1 files changed, 199 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_netlink.c b/drivers/scsi/scsi_netlink.c
new file mode 100644
index 0000000..1b59b27
--- /dev/null
+++ b/drivers/scsi/scsi_netlink.c
@@ -0,0 +1,199 @@
+/*
+ * scsi_netlink.c - SCSI Transport Netlink Interface
+ *
+ * Copyright (C) 2006 James Smart, Emulex Corporation
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+#include <linux/time.h>
+#include <linux/jiffies.h>
+#include <linux/security.h>
+#include <net/sock.h>
+#include <net/netlink.h>
+
+#include <scsi/scsi_netlink.h>
+#include "scsi_priv.h"
+
+struct sock *scsi_nl_sock = NULL;
+EXPORT_SYMBOL_GPL(scsi_nl_sock);
+
+
+/**
+ * scsi_nl_rcv_msg -
+ * Receive message handler. Extracts message from a receive buffer.
+ * Validates message header and calls appropriate transport message handler
+ *
+ * @skb: socket receive buffer
+ *
+ **/
+static void
+scsi_nl_rcv_msg(struct sk_buff *skb)
+{
+ struct nlmsghdr *nlh;
+ struct scsi_nl_hdr *hdr;
+ uint32_t rlen;
+ int err;
+
+ while (skb->len >= NLMSG_SPACE(0)) {
+ err = 0;
+
+ nlh = (struct nlmsghdr *) skb->data;
+ if ((nlh->nlmsg_len < (sizeof(*nlh) + sizeof(*hdr))) ||
+ (skb->len < nlh->nlmsg_len)) {
+ printk(KERN_WARNING "%s: discarding partial skb\n",
+ __FUNCTION__);
+ return;
+ }
+
+ rlen = NLMSG_ALIGN(nlh->nlmsg_len);
+ if (rlen > skb->len)
+ rlen = skb->len;
+
+ if (nlh->nlmsg_type != SCSI_TRANSPORT_MSG) {
+ err = -EBADMSG;
+ goto next_msg;
+ }
+
+ hdr = NLMSG_DATA(nlh);
+ if ((hdr->version != SCSI_NL_VERSION) ||
+ (hdr->magic != SCSI_NL_MAGIC)) {
+ err = -EPROTOTYPE;
+ goto next_msg;
+ }
+
+ if (security_netlink_recv(skb, CAP_SYS_ADMIN)) {
+ err = -EPERM;
+ goto next_msg;
+ }
+
+ if (nlh->nlmsg_len < (sizeof(*nlh) + hdr->msglen)) {
+ printk(KERN_WARNING "%s: discarding partial message\n",
+ __FUNCTION__);
+ return;
+ }
+
+ /*
+ * We currently don't support anyone sending us a message
+ */
+
+next_msg:
+ if ((err) || (nlh->nlmsg_flags & NLM_F_ACK))
+ netlink_ack(skb, nlh, err);
+
+ skb_pull(skb, rlen);
+ }
+}
+
+
+/**
+ * scsi_nl_rcv_msg -
+ * Receive handler for a socket. Extracts a received message buffer from
+ * the socket, and starts message processing.
+ *
+ * @sk: socket
+ * @len: unused
+ *
+ **/
+static void
+scsi_nl_rcv(struct sock *sk, int len)
+{
+ struct sk_buff *skb;
+
+ while ((skb = skb_dequeue(&sk->sk_receive_queue))) {
+ scsi_nl_rcv_msg(skb);
+ kfree_skb(skb);
+ }
+}
+
+
+/**
+ * scsi_nl_rcv_event -
+ * Event handler for a netlink socket.
+ *
+ * @this: event notifier block
+ * @event: event type
+ * @ptr: event payload
+ *
+ **/
+static int
+scsi_nl_rcv_event(struct notifier_block *this, unsigned long event, void *ptr)
+{
+ struct netlink_notify *n = ptr;
+
+ if (n->protocol != NETLINK_SCSITRANSPORT)
+ return NOTIFY_DONE;
+
+ /*
+ * Currently, we are not tracking PID's, etc. There is nothing
+ * to handle.
+ */
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block scsi_netlink_notifier = {
+ .notifier_call = scsi_nl_rcv_event,
+};
+
+
+/**
+ * scsi_netlink_init -
+ * Called by SCSI subsystem to intialize the SCSI transport netlink
+ * interface
+ *
+ **/
+void
+scsi_netlink_init(void)
+{
+ int error;
+
+ error = netlink_register_notifier(&scsi_netlink_notifier);
+ if (error) {
+ printk(KERN_ERR "%s: register of event handler failed - %d\n",
+ __FUNCTION__, error);
+ return;
+ }
+
+ scsi_nl_sock = netlink_kernel_create(NETLINK_SCSITRANSPORT,
+ SCSI_NL_GRP_CNT, scsi_nl_rcv, THIS_MODULE);
+ if (!scsi_nl_sock) {
+ printk(KERN_ERR "%s: register of recieve handler failed\n",
+ __FUNCTION__);
+ netlink_unregister_notifier(&scsi_netlink_notifier);
+ }
+
+ return;
+}
+
+
+/**
+ * scsi_netlink_exit -
+ * Called by SCSI subsystem to disable the SCSI transport netlink
+ * interface
+ *
+ **/
+void
+scsi_netlink_exit(void)
+{
+ if (scsi_nl_sock) {
+ sock_release(scsi_nl_sock->sk_socket);
+ netlink_unregister_notifier(&scsi_netlink_notifier);
+ }
+
+ return;
+}
+
+
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