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 <net/net_namespace.h>
   7 #include <net/sock.h>
   8
   9 #include "internal.h"
  10
  11 static int pdiag_put_info(const struct packet_sock *po, struct sk_buff *nlskb)
  12 {
  13         struct packet_diag_info pinfo;
  14
  15         pinfo.pdi_index = po->ifindex;
  16         pinfo.pdi_version = po->tp_version;
  17         pinfo.pdi_reserve = po->tp_reserve;
  18         pinfo.pdi_copy_thresh = po->copy_thresh;
  19         pinfo.pdi_tstamp = po->tp_tstamp;
  20
  21         pinfo.pdi_flags = 0;
  22         if (po->running)
  23                 pinfo.pdi_flags |= PDI_RUNNING;
  24         if (po->auxdata)
  25                 pinfo.pdi_flags |= PDI_AUXDATA;
  26         if (po->origdev)
  27                 pinfo.pdi_flags |= PDI_ORIGDEV;
  28         if (po->has_vnet_hdr)
  29                 pinfo.pdi_flags |= PDI_VNETHDR;
  30         if (po->tp_loss)
  31                 pinfo.pdi_flags |= PDI_LOSS;
  32
  33         return nla_put(nlskb, PACKET_DIAG_INFO, sizeof(pinfo), &pinfo);
  34 }
  35
  36 static int pdiag_put_mclist(const struct packet_sock *po, struct sk_buff *nlskb)
  37 {
  38         struct nlattr *mca;
  39         struct packet_mclist *ml;
  40
  41         mca = nla_nest_start(nlskb, PACKET_DIAG_MCLIST);
  42         if (!mca)
  43                 return -EMSGSIZE;
  44
  45         rtnl_lock();
  46         for (ml = po->mclist; ml; ml = ml->next) {
  47                 struct packet_diag_mclist *dml;
  48
  49                 dml = nla_reserve_nohdr(nlskb, sizeof(*dml));
  50                 if (!dml) {
  51                         rtnl_unlock();
  52                         nla_nest_cancel(nlskb, mca);
  53                         return -EMSGSIZE;
  54                 }
  55
  56                 dml->pdmc_index = ml->ifindex;
  57                 dml->pdmc_type = ml->type;
  58                 dml->pdmc_alen = ml->alen;
  59                 dml->pdmc_count = ml->count;
  60                 BUILD_BUG_ON(sizeof(dml->pdmc_addr) != sizeof(ml->addr));
  61                 memcpy(dml->pdmc_addr, ml->addr, sizeof(ml->addr));
  62         }
  63
  64         rtnl_unlock();
  65         nla_nest_end(nlskb, mca);
  66
  67         return 0;
  68 }
  69
  70 static int pdiag_put_ring(struct packet_ring_buffer *ring, int ver, int nl_type,
  71                 struct sk_buff *nlskb)
  72 {
  73         struct packet_diag_ring pdr;
  74
  75         if (!ring->pg_vec || ((ver > TPACKET_V2) &&
  76                                 (nl_type == PACKET_DIAG_TX_RING)))
  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         return nlmsg_end(skb, nlh);
 180
 181 out_nlmsg_trim:
 182         nlmsg_cancel(skb, nlh);
 183         return -EMSGSIZE;
 184 }
 185
 186 static int packet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
 187 {
 188         int num = 0, s_num = cb->args[0];
 189         struct packet_diag_req *req;
 190         struct net *net;
 191         struct sock *sk;
 192         bool may_report_filterinfo;
 193
 194         net = sock_net(skb->sk);
 195         req = nlmsg_data(cb->nlh);
 196         may_report_filterinfo = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
 197
 198         mutex_lock(&net->packet.sklist_lock);
 199         sk_for_each(sk, &net->packet.sklist) {
 200                 if (!net_eq(sock_net(sk), net))
 201                         continue;
 202                 if (num < s_num)
 203                         goto next;
 204
 205                 if (sk_diag_fill(sk, skb, req,
 206                                  may_report_filterinfo,
 207                                  sk_user_ns(NETLINK_CB(cb->skb).sk),
 208                                  NETLINK_CB(cb->skb).portid,
 209                                  cb->nlh->nlmsg_seq, NLM_F_MULTI,
 210                                  sock_i_ino(sk)) < 0)
 211                         goto done;
 212 next:
 213                 num++;
 214         }
 215 done:
 216         mutex_unlock(&net->packet.sklist_lock);
 217         cb->args[0] = num;
 218
 219         return skb->len;
 220 }
 221
 222 static int packet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
 223 {
 224         int hdrlen = sizeof(struct packet_diag_req);
 225         struct net *net = sock_net(skb->sk);
 226         struct packet_diag_req *req;
 227
 228         if (nlmsg_len(h) < hdrlen)
 229                 return -EINVAL;
 230
 231         req = nlmsg_data(h);
 232         /* Make it possible to support protocol filtering later */
 233         if (req->sdiag_protocol)
 234                 return -EINVAL;
 235
 236         if (h->nlmsg_flags & NLM_F_DUMP) {
 237                 struct netlink_dump_control c = {
 238                         .dump = packet_diag_dump,
 239                 };
 240                 return netlink_dump_start(net->diag_nlsk, skb, h, &c);
 241         } else
 242                 return -EOPNOTSUPP;
 243 }
 244
 245 static const struct sock_diag_handler packet_diag_handler = {
 246         .family = AF_PACKET,
 247         .dump = packet_diag_handler_dump,
 248 };
 249
 250 static int __init packet_diag_init(void)
 251 {
 252         return sock_diag_register(&packet_diag_handler);
 253 }
 254
 255 static void __exit packet_diag_exit(void)
 256 {
 257         sock_diag_unregister(&packet_diag_handler);
 258 }
 259
 260 module_init(packet_diag_init);
 261 module_exit(packet_diag_exit);
 262 MODULE_LICENSE("GPL");
 263 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 17 /* AF_PACKET */);