diff options
Diffstat (limited to 'net/core/neighbour.c')
| -rw-r--r-- | net/core/neighbour.c | 204 |
1 files changed, 193 insertions, 11 deletions
diff --git a/net/core/neighbour.c b/net/core/neighbour.c index fb4372cb1de1..43687c9abe1d 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -1751,6 +1751,18 @@ static struct neigh_table *neigh_find_table(int family) return tbl; } +const struct nla_policy nda_policy[NDA_MAX+1] = { + [NDA_DST] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN }, + [NDA_LLADDR] = { .type = NLA_BINARY, .len = MAX_ADDR_LEN }, + [NDA_CACHEINFO] = { .len = sizeof(struct nda_cacheinfo) }, + [NDA_PROBES] = { .type = NLA_U32 }, + [NDA_VLAN] = { .type = NLA_U16 }, + [NDA_PORT] = { .type = NLA_U16 }, + [NDA_VNI] = { .type = NLA_U32 }, + [NDA_IFINDEX] = { .type = NLA_U32 }, + [NDA_MASTER] = { .type = NLA_U32 }, +}; + static int neigh_delete(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { @@ -2711,6 +2723,186 @@ static int neigh_dump_info(struct sk_buff *skb, struct netlink_callback *cb) return skb->len; } +static int neigh_valid_get_req(const struct nlmsghdr *nlh, + struct neigh_table **tbl, + void **dst, int *dev_idx, u8 *ndm_flags, + struct netlink_ext_ack *extack) +{ + struct nlattr *tb[NDA_MAX + 1]; + struct ndmsg *ndm; + int err, i; + + if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ndm))) { + NL_SET_ERR_MSG(extack, "Invalid header for neighbor get request"); + return -EINVAL; + } + + ndm = nlmsg_data(nlh); + if (ndm->ndm_pad1 || ndm->ndm_pad2 || ndm->ndm_state || + ndm->ndm_type) { + NL_SET_ERR_MSG(extack, "Invalid values in header for neighbor get request"); + return -EINVAL; + } + + if (ndm->ndm_flags & ~NTF_PROXY) { + NL_SET_ERR_MSG(extack, "Invalid flags in header for neighbor get request"); + return -EINVAL; + } + + err = nlmsg_parse_strict(nlh, sizeof(struct ndmsg), tb, NDA_MAX, + nda_policy, extack); + if (err < 0) + return err; + + *ndm_flags = ndm->ndm_flags; + *dev_idx = ndm->ndm_ifindex; + *tbl = neigh_find_table(ndm->ndm_family); + if (*tbl == NULL) { + NL_SET_ERR_MSG(extack, "Unsupported family in header for neighbor get request"); + return -EAFNOSUPPORT; + } + + for (i = 0; i <= NDA_MAX; ++i) { + if (!tb[i]) + continue; + + switch (i) { + case NDA_DST: + if (nla_len(tb[i]) != (int)(*tbl)->key_len) { + NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request"); + return -EINVAL; + } + *dst = nla_data(tb[i]); + break; + default: + NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request"); + return -EINVAL; + } + } + + return 0; +} + +static inline size_t neigh_nlmsg_size(void) +{ + return NLMSG_ALIGN(sizeof(struct ndmsg)) + + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */ + + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */ + + nla_total_size(sizeof(struct nda_cacheinfo)) + + nla_total_size(4) /* NDA_PROBES */ + + nla_total_size(1); /* NDA_PROTOCOL */ +} + +static int neigh_get_reply(struct net *net, struct neighbour *neigh, + u32 pid, u32 seq) +{ + struct sk_buff *skb; + int err = 0; + + skb = nlmsg_new(neigh_nlmsg_size(), GFP_KERNEL); + if (!skb) + return -ENOBUFS; + + err = neigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0); + if (err) { + kfree_skb(skb); + goto errout; + } + + err = rtnl_unicast(skb, net, pid); +errout: + return err; +} + +static inline size_t pneigh_nlmsg_size(void) +{ + return NLMSG_ALIGN(sizeof(struct ndmsg)) + + nla_total_size(MAX_ADDR_LEN); /* NDA_DST */ + + nla_total_size(1); /* NDA_PROTOCOL */ +} + +static int pneigh_get_reply(struct net *net, struct pneigh_entry *neigh, + u32 pid, u32 seq, struct neigh_table *tbl) +{ + struct sk_buff *skb; + int err = 0; + + skb = nlmsg_new(pneigh_nlmsg_size(), GFP_KERNEL); + if (!skb) + return -ENOBUFS; + + err = pneigh_fill_info(skb, neigh, pid, seq, RTM_NEWNEIGH, 0, tbl); + if (err) { + kfree_skb(skb); + goto errout; + } + + err = rtnl_unicast(skb, net, pid); +errout: + return err; +} + +static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh, + struct netlink_ext_ack *extack) +{ + struct net *net = sock_net(in_skb->sk); + struct net_device *dev = NULL; + struct neigh_table *tbl = NULL; + struct neighbour *neigh; + void *dst = NULL; + u8 ndm_flags = 0; + int dev_idx = 0; + int err; + + err = neigh_valid_get_req(nlh, &tbl, &dst, &dev_idx, &ndm_flags, + extack); + if (err < 0) + return err; + + if (dev_idx) { + dev = __dev_get_by_index(net, dev_idx); + if (!dev) { + NL_SET_ERR_MSG(extack, "Unknown device ifindex"); + return -ENODEV; + } + } + + if (!dst) { + NL_SET_ERR_MSG(extack, "Network address not specified"); + return -EINVAL; + } + + if (ndm_flags & NTF_PROXY) { + struct pneigh_entry *pn; + + pn = pneigh_lookup(tbl, net, dst, dev, 0); + if (!pn) { + NL_SET_ERR_MSG(extack, "Proxy neighbour entry not found"); + return -ENOENT; + } + return pneigh_get_reply(net, pn, NETLINK_CB(in_skb).portid, + nlh->nlmsg_seq, tbl); + } + + if (!dev) { + NL_SET_ERR_MSG(extack, "No device specified"); + return -EINVAL; + } + + neigh = neigh_lookup(tbl, dst, dev); + if (!neigh) { + NL_SET_ERR_MSG(extack, "Neighbour entry not found"); + return -ENOENT; + } + + err = neigh_get_reply(net, neigh, NETLINK_CB(in_skb).portid, + nlh->nlmsg_seq); + + neigh_release(neigh); + + return err; +} + void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void *), void *cookie) { int chain; @@ -3118,16 +3310,6 @@ static const struct seq_operations neigh_stat_seq_ops = { }; #endif /* CONFIG_PROC_FS */ -static inline size_t neigh_nlmsg_size(void) -{ - return NLMSG_ALIGN(sizeof(struct ndmsg)) - + nla_total_size(MAX_ADDR_LEN) /* NDA_DST */ - + nla_total_size(MAX_ADDR_LEN) /* NDA_LLADDR */ - + nla_total_size(sizeof(struct nda_cacheinfo)) - + nla_total_size(4) /* NDA_PROBES */ - + nla_total_size(1); /* NDA_PROTOCOL */ -} - static void __neigh_notify(struct neighbour *n, int type, int flags, u32 pid) { @@ -3511,7 +3693,7 @@ static int __init neigh_init(void) { rtnl_register(PF_UNSPEC, RTM_NEWNEIGH, neigh_add, NULL, 0); rtnl_register(PF_UNSPEC, RTM_DELNEIGH, neigh_delete, NULL, 0); - rtnl_register(PF_UNSPEC, RTM_GETNEIGH, NULL, neigh_dump_info, 0); + rtnl_register(PF_UNSPEC, RTM_GETNEIGH, neigh_get, neigh_dump_info, 0); rtnl_register(PF_UNSPEC, RTM_GETNEIGHTBL, NULL, neightbl_dump_info, 0); |