blob: 370c78cc1cb562f20af68017489a78b6650374a0 [file] [log] [blame]
James Smart84314fd2006-08-18 17:30:09 -04001/*
2 * scsi_netlink.c - SCSI Transport Netlink Interface
3 *
4 * Copyright (C) 2006 James Smart, Emulex Corporation
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21#include <linux/time.h>
22#include <linux/jiffies.h>
23#include <linux/security.h>
24#include <net/sock.h>
25#include <net/netlink.h>
26
27#include <scsi/scsi_netlink.h>
28#include "scsi_priv.h"
29
30struct sock *scsi_nl_sock = NULL;
31EXPORT_SYMBOL_GPL(scsi_nl_sock);
32
33
34/**
Rob Landleyeb44820c2007-11-03 13:30:39 -050035 * scsi_nl_rcv_msg - Receive message handler.
36 * @skb: socket receive buffer
37 *
38 * Description: Extracts message from a receive buffer.
James Smart84314fd2006-08-18 17:30:09 -040039 * Validates message header and calls appropriate transport message handler
40 *
James Smart84314fd2006-08-18 17:30:09 -040041 *
42 **/
43static void
44scsi_nl_rcv_msg(struct sk_buff *skb)
45{
46 struct nlmsghdr *nlh;
47 struct scsi_nl_hdr *hdr;
48 uint32_t rlen;
49 int err;
50
51 while (skb->len >= NLMSG_SPACE(0)) {
52 err = 0;
53
Arnaldo Carvalho de Melob529ccf2007-04-25 19:08:35 -070054 nlh = nlmsg_hdr(skb);
James Smart84314fd2006-08-18 17:30:09 -040055 if ((nlh->nlmsg_len < (sizeof(*nlh) + sizeof(*hdr))) ||
56 (skb->len < nlh->nlmsg_len)) {
57 printk(KERN_WARNING "%s: discarding partial skb\n",
58 __FUNCTION__);
59 return;
60 }
61
62 rlen = NLMSG_ALIGN(nlh->nlmsg_len);
63 if (rlen > skb->len)
64 rlen = skb->len;
65
66 if (nlh->nlmsg_type != SCSI_TRANSPORT_MSG) {
67 err = -EBADMSG;
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -070068 return;
James Smart84314fd2006-08-18 17:30:09 -040069 }
70
71 hdr = NLMSG_DATA(nlh);
72 if ((hdr->version != SCSI_NL_VERSION) ||
73 (hdr->magic != SCSI_NL_MAGIC)) {
74 err = -EPROTOTYPE;
75 goto next_msg;
76 }
77
78 if (security_netlink_recv(skb, CAP_SYS_ADMIN)) {
79 err = -EPERM;
80 goto next_msg;
81 }
82
83 if (nlh->nlmsg_len < (sizeof(*nlh) + hdr->msglen)) {
84 printk(KERN_WARNING "%s: discarding partial message\n",
85 __FUNCTION__);
86 return;
87 }
88
89 /*
90 * We currently don't support anyone sending us a message
91 */
92
93next_msg:
94 if ((err) || (nlh->nlmsg_flags & NLM_F_ACK))
95 netlink_ack(skb, nlh, err);
96
97 skb_pull(skb, rlen);
98 }
99}
100
101
102/**
Rob Landleyeb44820c2007-11-03 13:30:39 -0500103 * scsi_nl_rcv_event - Event handler for a netlink socket.
James Smart84314fd2006-08-18 17:30:09 -0400104 * @this: event notifier block
105 * @event: event type
106 * @ptr: event payload
107 *
108 **/
109static int
110scsi_nl_rcv_event(struct notifier_block *this, unsigned long event, void *ptr)
111{
112 struct netlink_notify *n = ptr;
113
114 if (n->protocol != NETLINK_SCSITRANSPORT)
115 return NOTIFY_DONE;
116
117 /*
118 * Currently, we are not tracking PID's, etc. There is nothing
119 * to handle.
120 */
121
122 return NOTIFY_DONE;
123}
124
125static struct notifier_block scsi_netlink_notifier = {
126 .notifier_call = scsi_nl_rcv_event,
127};
128
129
130/**
Rob Landleyeb44820c2007-11-03 13:30:39 -0500131 * scsi_netlink_init - Called by SCSI subsystem to intialize the SCSI transport netlink interface
James Smart84314fd2006-08-18 17:30:09 -0400132 *
133 **/
134void
135scsi_netlink_init(void)
136{
137 int error;
138
139 error = netlink_register_notifier(&scsi_netlink_notifier);
140 if (error) {
141 printk(KERN_ERR "%s: register of event handler failed - %d\n",
142 __FUNCTION__, error);
143 return;
144 }
145
Eric W. Biedermanb4b51022007-09-12 13:05:38 +0200146 scsi_nl_sock = netlink_kernel_create(&init_net, NETLINK_SCSITRANSPORT,
Denis V. Lunevcd40b7d2007-10-10 21:15:29 -0700147 SCSI_NL_GRP_CNT, scsi_nl_rcv_msg, NULL,
Patrick McHardyaf65bdf2007-04-20 14:14:21 -0700148 THIS_MODULE);
James Smart84314fd2006-08-18 17:30:09 -0400149 if (!scsi_nl_sock) {
150 printk(KERN_ERR "%s: register of recieve handler failed\n",
151 __FUNCTION__);
152 netlink_unregister_notifier(&scsi_netlink_notifier);
153 }
154
155 return;
156}
157
158
159/**
Rob Landleyeb44820c2007-11-03 13:30:39 -0500160 * scsi_netlink_exit - Called by SCSI subsystem to disable the SCSI transport netlink interface
James Smart84314fd2006-08-18 17:30:09 -0400161 *
162 **/
163void
164scsi_netlink_exit(void)
165{
166 if (scsi_nl_sock) {
Denis V. Lunevb7c6ba62008-01-28 14:41:19 -0800167 netlink_kernel_release(scsi_nl_sock);
James Smart84314fd2006-08-18 17:30:09 -0400168 netlink_unregister_notifier(&scsi_netlink_notifier);
169 }
170
171 return;
172}
173
174