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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * scsi_netlink.c - SCSI Transport Netlink Interface4 *5 * Copyright (C) 2006 James Smart, Emulex Corporation6 */7#include <linux/time.h>8#include <linux/jiffies.h>9#include <linux/security.h>10#include <linux/delay.h>11#include <linux/slab.h>12#include <linux/export.h>13#include <net/sock.h>14#include <net/netlink.h>15 16#include <scsi/scsi_netlink.h>17#include "scsi_priv.h"18 19struct sock *scsi_nl_sock = NULL;20EXPORT_SYMBOL_GPL(scsi_nl_sock);21 22/**23 * scsi_nl_rcv_msg - Receive message handler.24 * @skb: socket receive buffer25 *26 * Description: Extracts message from a receive buffer.27 * Validates message header and calls appropriate transport message handler28 *29 *30 **/31static void32scsi_nl_rcv_msg(struct sk_buff *skb)33{34 struct nlmsghdr *nlh;35 struct scsi_nl_hdr *hdr;36 u32 rlen;37 int err, tport;38 39 while (skb->len >= NLMSG_HDRLEN) {40 err = 0;41 42 nlh = nlmsg_hdr(skb);43 if ((nlh->nlmsg_len < (sizeof(*nlh) + sizeof(*hdr))) ||44 (skb->len < nlh->nlmsg_len)) {45 printk(KERN_WARNING "%s: discarding partial skb\n",46 __func__);47 return;48 }49 50 rlen = NLMSG_ALIGN(nlh->nlmsg_len);51 if (rlen > skb->len)52 rlen = skb->len;53 54 if (nlh->nlmsg_type != SCSI_TRANSPORT_MSG) {55 err = -EBADMSG;56 goto next_msg;57 }58 59 hdr = nlmsg_data(nlh);60 if ((hdr->version != SCSI_NL_VERSION) ||61 (hdr->magic != SCSI_NL_MAGIC)) {62 err = -EPROTOTYPE;63 goto next_msg;64 }65 66 if (!netlink_capable(skb, CAP_SYS_ADMIN)) {67 err = -EPERM;68 goto next_msg;69 }70 71 if (nlh->nlmsg_len < (sizeof(*nlh) + hdr->msglen)) {72 printk(KERN_WARNING "%s: discarding partial message\n",73 __func__);74 goto next_msg;75 }76 77 /*78 * Deliver message to the appropriate transport79 */80 tport = hdr->transport;81 if (tport == SCSI_NL_TRANSPORT) {82 switch (hdr->msgtype) {83 case SCSI_NL_SHOST_VENDOR:84 /* Locate the driver that corresponds to the message */85 err = -ESRCH;86 break;87 default:88 err = -EBADR;89 break;90 }91 if (err)92 printk(KERN_WARNING "%s: Msgtype %d failed - err %d\n",93 __func__, hdr->msgtype, err);94 }95 else96 err = -ENOENT;97 98next_msg:99 if ((err) || (nlh->nlmsg_flags & NLM_F_ACK))100 netlink_ack(skb, nlh, err, NULL);101 102 skb_pull(skb, rlen);103 }104}105 106/**107 * scsi_netlink_init - Called by SCSI subsystem to initialize108 * the SCSI transport netlink interface109 *110 **/111void112scsi_netlink_init(void)113{114 struct netlink_kernel_cfg cfg = {115 .input = scsi_nl_rcv_msg,116 .groups = SCSI_NL_GRP_CNT,117 };118 119 scsi_nl_sock = netlink_kernel_create(&init_net, NETLINK_SCSITRANSPORT,120 &cfg);121 if (!scsi_nl_sock) {122 printk(KERN_ERR "%s: register of receive handler failed\n",123 __func__);124 return;125 }126 127 return;128}129 130 131/**132 * scsi_netlink_exit - Called by SCSI subsystem to disable the SCSI transport netlink interface133 *134 **/135void136scsi_netlink_exit(void)137{138 if (scsi_nl_sock) {139 netlink_kernel_release(scsi_nl_sock);140 }141 142 return;143}144 145