net/packet/diag.c

   1 #include <linux/module.h>
   2 #include <linux/sock_diag.h>
   3 #include <linux/net.h>
   4 #include <linux/netdevice.h>
   5 #include <linux/packet_diag.h>
   6 #include <linux/percpu.h>
   7 #include <net/net_namespace.h>
   8 #include <net/sock.h>
   9
  10 #include "internal.h"
  11
  12 static int pdiag_put_info(const struct packet_sock *po, struct sk_buff *nlskb)
  13 {
  14         struct packet_diag_info pinfo;
  15
  16         pinfo.pdi_index = po->ifindex;
  17         pinfo.pdi_version = po->tp_version;
  18         pinfo.pdi_reserve = po->tp_reserve;
  19         pinfo.pdi_copy_thresh = po->copy_thresh;
  20         pinfo.pdi_tstamp = po->tp_tstamp;
  21
  22         pinfo.pdi_flags = 0;
  23         if (po->running)
  24                 pinfo.pdi_flags |= PDI_RUNNING;
  25         if (po->auxdata)
  26                 pinfo.pdi_flags |= PDI_AUXDATA;
  27         if (po->origdev)
  28                 pinfo.pdi_flags |= PDI_ORIGDEV;
  29         if (po->has_vnet_hdr)
  30                 pinfo.pdi_flags |= PDI_VNETHDR;
  31         if (po->tp_loss)
  32                 pinfo.pdi_flags |= PDI_LOSS;
  33
  34         return nla_put(nlskb, PACKET_DIAG_INFO, sizeof(pinfo), &pinfo);
  35 }
  36
  37 static int pdiag_put_mclist(const struct packet_sock *po, struct sk_buff *nlskb)
  38 {
  39         struct nlattr *mca;
  40         struct packet_mclist *ml;
  41
  42         mca = nla_nest_start(nlskb, PACKET_DIAG_MCLIST);
  43         if (!mca)
  44                 return -EMSGSIZE;
  45
  46         rtnl_lock();
  47         for (ml = po->mclist; ml; ml = ml->next) {
  48                 struct packet_diag_mclist *dml;
  49
  50                 dml = nla_reserve_nohdr(nlskb, sizeof(*dml));
  51                 if (!dml) {
  52                         rtnl_unlock();
  53                         nla_nest_cancel(nlskb, mca);
  54                         return -EMSGSIZE;
  55                 }
  56
  57                 dml->pdmc_index = ml->ifindex;
  58                 dml->pdmc_type = ml->type;
  59                 dml->pdmc_alen = ml->alen;
  60                 dml->pdmc_count = ml->count;
  61                 BUILD_BUG_ON(sizeof(dml->pdmc_addr) != sizeof(ml->addr));
  62                 memcpy(dml->pdmc_addr, ml->addr, sizeof(ml->addr));
  63         }
  64
  65         rtnl_unlock();
  66         nla_nest_end(nlskb, mca);
  67
  68         return 0;
  69 }
  70
  71 static int pdiag_put_ring(struct packet_ring_buffer *ring, int ver, int nl_type,
  72                 struct sk_buff *nlskb)
  73 {
  74         struct packet_diag_ring pdr;
  75
  76         if (!ring->pg_vec)
  77                 return 0;
  78
  79         pdr.pdr_block_size = ring->pg_vec_pages << PAGE_SHIFT;
  80         pdr.pdr_block_nr = ring->pg_vec_len;
  81         pdr.pdr_frame_size = ring->frame_size;
  82         pdr.pdr_frame_nr = ring->frame_max + 1;
  83
  84         if (ver > TPACKET_V2) {
  85                 pdr.pdr_retire_tmo = ring->prb_bdqc.retire_blk_tov;
  86                 pdr.pdr_sizeof_priv = ring->prb_bdqc.blk_sizeof_priv;
  87                 pdr.pdr_features = ring->prb_bdqc.feature_req_word;
  88         } else {
  89                 pdr.pdr_retire_tmo = 0;
  90                 pdr.pdr_sizeof_priv = 0;
  91                 pdr.pdr_features = 0;
  92         }
  93
  94         return nla_put(nlskb, nl_type, sizeof(pdr), &pdr);
  95 }
  96
  97 static int pdiag_put_rings_cfg(struct packet_sock *po, struct sk_buff *skb)
  98 {
  99         int ret;
 100
 101         mutex_lock(&po->pg_vec_lock);
 102         ret = pdiag_put_ring(&po->rx_ring, po->tp_version,
 103                         PACKET_DIAG_RX_RING, skb);
 104         if (!ret)
 105                 ret = pdiag_put_ring(&po->tx_ring, po->tp_version,
 106                                 PACKET_DIAG_TX_RING, skb);
 107         mutex_unlock(&po->pg_vec_lock);
 108
 109         return ret;
 110 }
 111
 112 static int pdiag_put_fanout(struct packet_sock *po, struct sk_buff *nlskb)
 113 {
 114         int ret = 0;
 115
 116         mutex_lock(&fanout_mutex);
 117         if (po->fanout) {
 118                 u32 val;
 119
 120                 val = (u32)po->fanout->id | ((u32)po->fanout->type << 16);
 121                 ret = nla_put_u32(nlskb, PACKET_DIAG_FANOUT, val);
 122         }
 123         mutex_unlock(&fanout_mutex);
 124
 125         return ret;
 126 }
 127
 128 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
 129                         struct packet_diag_req *req,
 130                         bool may_report_filterinfo,
 131                         struct user_namespace *user_ns,
 132                         u32 portid, u32 seq, u32 flags, int sk_ino)
 133 {
 134         struct nlmsghdr *nlh;
 135         struct packet_diag_msg *rp;
 136         struct packet_sock *po = pkt_sk(sk);
 137
 138         nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rp), flags);
 139         if (!nlh)
 140                 return -EMSGSIZE;
 141
 142         rp = nlmsg_data(nlh);
 143         rp->pdiag_family = AF_PACKET;
 144         rp->pdiag_type = sk->sk_type;
 145         rp->pdiag_num = ntohs(po->num);
 146         rp->pdiag_ino = sk_ino;
 147         sock_diag_save_cookie(sk, rp->pdiag_cookie);
 148
 149         if ((req->pdiag_show & PACKET_SHOW_INFO) &&
 150                         pdiag_put_info(po, skb))
 151                 goto out_nlmsg_trim;
 152
 153         if ((req->pdiag_show & PACKET_SHOW_INFO) &&
 154             nla_put_u32(skb, PACKET_DIAG_UID,
 155                         from_kuid_munged(user_ns, sock_i_uid(sk))))
 156                 goto out_nlmsg_trim;
 157
 158         if ((req->pdiag_show & PACKET_SHOW_MCLIST) &&
 159                         pdiag_put_mclist(po, skb))
 160                 goto out_nlmsg_trim;
 161
 162         if ((req->pdiag_show & PACKET_SHOW_RING_CFG) &&
 163                         pdiag_put_rings_cfg(po, skb))
 164                 goto out_nlmsg_trim;
 165
 166         if ((req->pdiag_show & PACKET_SHOW_FANOUT) &&
 167                         pdiag_put_fanout(po, skb))
 168                 goto out_nlmsg_trim;
 169
 170         if ((req->pdiag_show & PACKET_SHOW_MEMINFO) &&
 171             sock_diag_put_meminfo(sk, skb, PACKET_DIAG_MEMINFO))
 172                 goto out_nlmsg_trim;
 173
 174         if ((req->pdiag_show & PACKET_SHOW_FILTER) &&
 175             sock_diag_put_filterinfo(may_report_filterinfo, sk, skb,
 176                                      PACKET_DIAG_FILTER))
 177                 goto out_nlmsg_trim;
 178
 179         nlmsg_end(skb, nlh);
 180         return 0;
 181
 182 out_nlmsg_trim:
 183         nlmsg_cancel(skb, nlh);
 184         return -EMSGSIZE;
 185 }
 186
 187 static int packet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 188 {
 189         int num = 0, s_num = cb->args[0];
 190         struct packet_diag_req *req;
 191         struct net *net;
 192         struct sock *sk;
 193         bool may_report_filterinfo;
 194
 195         net = sock_net(skb->sk);
 196         req = nlmsg_data(cb->nlh);
 197         may_report_filterinfo = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
 198
 199         mutex_lock(&net->packet.sklist_lock);
 200         sk_for_each(sk, &net->packet.sklist) {
 201                 if (!net_eq(sock_net(sk), net))
 202                         continue;
 203                 if (num < s_num)
 204                         goto next;
 205
 206                 if (sk_diag_fill(sk, skb, req,
 207                                  may_report_filterinfo,
 208                                  sk_user_ns(NETLINK_CB(cb->skb).sk),
 209                                  NETLINK_CB(cb->skb).portid,
 210                                  cb->nlh->nlmsg_seq, NLM_F_MULTI,
 211                                  sock_i_ino(sk)) < 0)
 212                         goto done;
 213 next:
 214                 num++;
 215         }
 216 done:
 217         mutex_unlock(&net->packet.sklist_lock);
 218         cb->args[0] = num;
 219
 220         return skb->len;
 221 }
 222
 223 static int packet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
 224 {
 225         int hdrlen = sizeof(struct packet_diag_req);
 226         struct net *net = sock_net(skb->sk);
 227         struct packet_diag_req *req;
 228
 229         if (nlmsg_len(h) < hdrlen)
 230                 return -EINVAL;
 231
 232         req = nlmsg_data(h);
 233         /* Make it possible to support protocol filtering later */
 234         if (req->sdiag_protocol)
 235                 return -EINVAL;
 236
 237         if (h->nlmsg_flags & NLM_F_DUMP) {
 238                 struct netlink_dump_control c = {
 239                         .dump = packet_diag_dump,
 240                 };
 241                 return netlink_dump_start(net->diag_nlsk, skb, h, &c);
 242         } else
 243                 return -EOPNOTSUPP;
 244 }
 245
 246 static const struct sock_diag_handler packet_diag_handler = {
 247         .family = AF_PACKET,
 248         .dump = packet_diag_handler_dump,
 249 };
 250
 251 static int __init packet_diag_init(void)
 252 {
 253         return sock_diag_register(&packet_diag_handler);
 254 }
 255
 256 static void __exit packet_diag_exit(void)
 257 {
 258         sock_diag_unregister(&packet_diag_handler);
 259 }
 260
 261 module_init(packet_diag_init);
 262 module_exit(packet_diag_exit);
 263 MODULE_LICENSE("GPL");
 264 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 17 /* AF_PACKET */);