James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 1 | /* |
| 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 | |
| 30 | struct sock *scsi_nl_sock = NULL; |
| 31 | EXPORT_SYMBOL_GPL(scsi_nl_sock); |
| 32 | |
| 33 | |
| 34 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 35 | * scsi_nl_rcv_msg - Receive message handler. |
| 36 | * @skb: socket receive buffer |
| 37 | * |
| 38 | * Description: Extracts message from a receive buffer. |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 39 | * Validates message header and calls appropriate transport message handler |
| 40 | * |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 41 | * |
| 42 | **/ |
| 43 | static void |
| 44 | scsi_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 Melo | b529ccf | 2007-04-25 19:08:35 -0700 | [diff] [blame] | 54 | nlh = nlmsg_hdr(skb); |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 55 | 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. Lunev | cd40b7d | 2007-10-10 21:15:29 -0700 | [diff] [blame] | 68 | return; |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 69 | } |
| 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 | |
| 93 | next_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 Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 103 | * scsi_nl_rcv_event - Event handler for a netlink socket. |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 104 | * @this: event notifier block |
| 105 | * @event: event type |
| 106 | * @ptr: event payload |
| 107 | * |
| 108 | **/ |
| 109 | static int |
| 110 | scsi_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 | |
| 125 | static struct notifier_block scsi_netlink_notifier = { |
| 126 | .notifier_call = scsi_nl_rcv_event, |
| 127 | }; |
| 128 | |
| 129 | |
| 130 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 131 | * scsi_netlink_init - Called by SCSI subsystem to intialize the SCSI transport netlink interface |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 132 | * |
| 133 | **/ |
| 134 | void |
| 135 | scsi_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. Biederman | b4b5102 | 2007-09-12 13:05:38 +0200 | [diff] [blame] | 146 | scsi_nl_sock = netlink_kernel_create(&init_net, NETLINK_SCSITRANSPORT, |
Denis V. Lunev | cd40b7d | 2007-10-10 21:15:29 -0700 | [diff] [blame] | 147 | SCSI_NL_GRP_CNT, scsi_nl_rcv_msg, NULL, |
Patrick McHardy | af65bdf | 2007-04-20 14:14:21 -0700 | [diff] [blame] | 148 | THIS_MODULE); |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 149 | 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 Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 160 | * scsi_netlink_exit - Called by SCSI subsystem to disable the SCSI transport netlink interface |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 161 | * |
| 162 | **/ |
| 163 | void |
| 164 | scsi_netlink_exit(void) |
| 165 | { |
| 166 | if (scsi_nl_sock) { |
| 167 | sock_release(scsi_nl_sock->sk_socket); |
| 168 | netlink_unregister_notifier(&scsi_netlink_notifier); |
| 169 | } |
| 170 | |
| 171 | return; |
| 172 | } |
| 173 | |
| 174 | |