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 000000000000..1b59b27e887f
--- /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;
+}
+
+