net/irda/irnetlink.c

   1 /*
   2  * IrDA netlink layer, for stack configuration.
   3  *
   4  * Copyright (c) 2007 Samuel Ortiz <[email protected]>
   5  *
   6  * Partly based on the 802.11 nelink implementation
   7  * (see net/wireless/nl80211.c) which is:
   8  * Copyright 2006 Johannes Berg <[email protected]>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  *
  14  */
  15
  16 #include <linux/socket.h>
  17 #include <linux/irda.h>
  18 #include <linux/gfp.h>
  19 #include <net/net_namespace.h>
  20 #include <net/sock.h>
  21 #include <net/irda/irda.h>
  22 #include <net/irda/irlap.h>
  23 #include <net/genetlink.h>
  24
  25
  26
  27 static struct genl_family irda_nl_family;
  28
  29 static struct net_device * ifname_to_netdev(struct net *net, struct genl_info *info)
  30 {
  31         char * ifname;
  32
  33         if (!info->attrs[IRDA_NL_ATTR_IFNAME])
  34                 return NULL;
  35
  36         ifname = nla_data(info->attrs[IRDA_NL_ATTR_IFNAME]);
  37
  38         pr_debug("%s(): Looking for %s\n", __func__, ifname);
  39
  40         return dev_get_by_name(net, ifname);
  41 }
  42
  43 static int irda_nl_set_mode(struct sk_buff *skb, struct genl_info *info)
  44 {
  45         struct net_device * dev;
  46         struct irlap_cb * irlap;
  47         u32 mode;
  48
  49         if (!info->attrs[IRDA_NL_ATTR_MODE])
  50                 return -EINVAL;
  51
  52         mode = nla_get_u32(info->attrs[IRDA_NL_ATTR_MODE]);
  53
  54         pr_debug("%s(): Switching to mode: %d\n", __func__, mode);
  55
  56         dev = ifname_to_netdev(&init_net, info);
  57         if (!dev)
  58                 return -ENODEV;
  59
  60         irlap = (struct irlap_cb *)dev->atalk_ptr;
  61         if (!irlap) {
  62                 dev_put(dev);
  63                 return -ENODEV;
  64         }
  65
  66         irlap->mode = mode;
  67
  68         dev_put(dev);
  69
  70         return 0;
  71 }
  72
  73 static int irda_nl_get_mode(struct sk_buff *skb, struct genl_info *info)
  74 {
  75         struct net_device * dev;
  76         struct irlap_cb * irlap;
  77         struct sk_buff *msg;
  78         void *hdr;
  79         int ret = -ENOBUFS;
  80
  81         dev = ifname_to_netdev(&init_net, info);
  82         if (!dev)
  83                 return -ENODEV;
  84
  85         msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
  86         if (!msg) {
  87                 dev_put(dev);
  88                 return -ENOMEM;
  89         }
  90
  91         irlap = (struct irlap_cb *)dev->atalk_ptr;
  92         if (!irlap) {
  93                 ret = -ENODEV;
  94                 goto err_out;
  95         }
  96
  97         hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq,
  98                           &irda_nl_family, 0,  IRDA_NL_CMD_GET_MODE);
  99         if (hdr == NULL) {
 100                 ret = -EMSGSIZE;
 101                 goto err_out;
 102         }
 103
 104         if(nla_put_string(msg, IRDA_NL_ATTR_IFNAME,
 105                           dev->name))
 106                 goto err_out;
 107
 108         if(nla_put_u32(msg, IRDA_NL_ATTR_MODE, irlap->mode))
 109                 goto err_out;
 110
 111         genlmsg_end(msg, hdr);
 112
 113         return genlmsg_reply(msg, info);
 114
 115  err_out:
 116         nlmsg_free(msg);
 117         dev_put(dev);
 118
 119         return ret;
 120 }
 121
 122 static const struct nla_policy irda_nl_policy[IRDA_NL_ATTR_MAX + 1] = {
 123         [IRDA_NL_ATTR_IFNAME] = { .type = NLA_NUL_STRING,
 124                                   .len = IFNAMSIZ-1 },
 125         [IRDA_NL_ATTR_MODE] = { .type = NLA_U32 },
 126 };
 127
 128 static const struct genl_ops irda_nl_ops[] = {
 129         {
 130                 .cmd = IRDA_NL_CMD_SET_MODE,
 131                 .doit = irda_nl_set_mode,
 132                 .policy = irda_nl_policy,
 133                 .flags = GENL_ADMIN_PERM,
 134         },
 135         {
 136                 .cmd = IRDA_NL_CMD_GET_MODE,
 137                 .doit = irda_nl_get_mode,
 138                 .policy = irda_nl_policy,
 139                 /* can be retrieved by unprivileged users */
 140         },
 141
 142 };
 143
 144 static struct genl_family irda_nl_family __ro_after_init = {
 145         .name = IRDA_NL_NAME,
 146         .hdrsize = 0,
 147         .version = IRDA_NL_VERSION,
 148         .maxattr = IRDA_NL_CMD_MAX,
 149         .module = THIS_MODULE,
 150         .ops = irda_nl_ops,
 151         .n_ops = ARRAY_SIZE(irda_nl_ops),
 152 };
 153
 154 int __init irda_nl_register(void)
 155 {
 156         return genl_register_family(&irda_nl_family);
 157 }
 158
 159 void irda_nl_unregister(void)
 160 {
 161         genl_unregister_family(&irda_nl_family);
 162 }