From eaaa31392690c7609f7afeec5ba38a79d009842d Mon Sep 17 00:00:00 2001 From: Andrey Vagin Date: Thu, 21 Mar 2013 20:33:48 +0400 Subject: netlink: Diag core and basic socket info dumping (v2) The netlink_diag can be built as a module, just like it's done in unix sockets. The core dumping message carries the basic info about netlink sockets: family, type and protocol, portis, dst_group, dst_portid, state. Groups can be received as an optional parameter NETLINK_DIAG_GROUPS. Netlink sockets cab be filtered by protocols. The socket inode number and cookie is reserved for future per-socket info retrieving. The per-protocol filtering is also reserved for future by requiring the sdiag_protocol to be zero. The file /proc/net/netlink doesn't provide enough information for dumping netlink sockets. It doesn't provide dst_group, dst_portid, groups above 32. v2: fix NETLINK_DIAG_MAX. Now it's equal to the last constant. Acked-by: Pavel Emelyanov Cc: "David S. Miller" Cc: Eric Dumazet Cc: Pablo Neira Ayuso Cc: "Eric W. Biederman" Cc: Gao feng Cc: Thomas Graf Signed-off-by: Andrey Vagin Signed-off-by: David S. Miller --- include/uapi/linux/netlink_diag.h | 42 +++++++++ net/Kconfig | 1 + net/netlink/Kconfig | 10 ++ net/netlink/Makefile | 3 + net/netlink/diag.c | 188 ++++++++++++++++++++++++++++++++++++++ 5 files changed, 244 insertions(+) create mode 100644 include/uapi/linux/netlink_diag.h create mode 100644 net/netlink/Kconfig create mode 100644 net/netlink/diag.c diff --git a/include/uapi/linux/netlink_diag.h b/include/uapi/linux/netlink_diag.h new file mode 100644 index 000000000000..88009a31cd06 --- /dev/null +++ b/include/uapi/linux/netlink_diag.h @@ -0,0 +1,42 @@ +#ifndef __NETLINK_DIAG_H__ +#define __NETLINK_DIAG_H__ + +#include + +struct netlink_diag_req { + __u8 sdiag_family; + __u8 sdiag_protocol; + __u16 pad; + __u32 ndiag_ino; + __u32 ndiag_show; + __u32 ndiag_cookie[2]; +}; + +struct netlink_diag_msg { + __u8 ndiag_family; + __u8 ndiag_type; + __u8 ndiag_protocol; + __u8 ndiag_state; + + __u32 ndiag_portid; + __u32 ndiag_dst_portid; + __u32 ndiag_dst_group; + __u32 ndiag_ino; + __u32 ndiag_cookie[2]; +}; + +enum { + NETLINK_DIAG_MEMINFO, + NETLINK_DIAG_GROUPS, + + __NETLINK_DIAG_MAX, +}; + +#define NETLINK_DIAG_MAX (__NETLINK_DIAG_MAX - 1) + +#define NDIAG_PROTO_ALL ((__u8) ~0) + +#define NDIAG_SHOW_MEMINFO 0x00000001 /* show memory info of a socket */ +#define NDIAG_SHOW_GROUPS 0x00000002 /* show groups of a netlink socket */ + +#endif diff --git a/net/Kconfig b/net/Kconfig index 6f676ab885be..2ddc9046868e 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -217,6 +217,7 @@ source "net/dns_resolver/Kconfig" source "net/batman-adv/Kconfig" source "net/openvswitch/Kconfig" source "net/vmw_vsock/Kconfig" +source "net/netlink/Kconfig" config RPS boolean diff --git a/net/netlink/Kconfig b/net/netlink/Kconfig new file mode 100644 index 000000000000..5d6e8c05b3d4 --- /dev/null +++ b/net/netlink/Kconfig @@ -0,0 +1,10 @@ +# +# Netlink Sockets +# + +config NETLINK_DIAG + tristate "NETLINK: socket monitoring interface" + default n + ---help--- + Support for NETLINK socket monitoring interface used by the ss tool. + If unsure, say Y. diff --git a/net/netlink/Makefile b/net/netlink/Makefile index bdd6ddf4e95b..e837917f6c03 100644 --- a/net/netlink/Makefile +++ b/net/netlink/Makefile @@ -3,3 +3,6 @@ # obj-y := af_netlink.o genetlink.o + +obj-$(CONFIG_NETLINK_DIAG) += netlink_diag.o +netlink_diag-y := diag.o diff --git a/net/netlink/diag.c b/net/netlink/diag.c new file mode 100644 index 000000000000..5ffb1d1cf402 --- /dev/null +++ b/net/netlink/diag.c @@ -0,0 +1,188 @@ +#include + +#include +#include +#include +#include + +#include "af_netlink.h" + +static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb) +{ + struct netlink_sock *nlk = nlk_sk(sk); + + if (nlk->groups == NULL) + return 0; + + return nla_put(nlskb, NETLINK_DIAG_GROUPS, NLGRPSZ(nlk->ngroups), + nlk->groups); +} + +static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, + struct netlink_diag_req *req, + u32 portid, u32 seq, u32 flags, int sk_ino) +{ + struct nlmsghdr *nlh; + struct netlink_diag_msg *rep; + struct netlink_sock *nlk = nlk_sk(sk); + + nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep), + flags); + if (!nlh) + return -EMSGSIZE; + + rep = nlmsg_data(nlh); + rep->ndiag_family = AF_NETLINK; + rep->ndiag_type = sk->sk_type; + rep->ndiag_protocol = sk->sk_protocol; + rep->ndiag_state = sk->sk_state; + + rep->ndiag_ino = sk_ino; + rep->ndiag_portid = nlk->portid; + rep->ndiag_dst_portid = nlk->dst_portid; + rep->ndiag_dst_group = nlk->dst_group; + sock_diag_save_cookie(sk, rep->ndiag_cookie); + + if ((req->ndiag_show & NDIAG_SHOW_GROUPS) && + sk_diag_dump_groups(sk, skb)) + goto out_nlmsg_trim; + + if ((req->ndiag_show & NDIAG_SHOW_MEMINFO) && + sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO)) + goto out_nlmsg_trim; + + return nlmsg_end(skb, nlh); + +out_nlmsg_trim: + nlmsg_cancel(skb, nlh); + return -EMSGSIZE; +} + +static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, + int protocol, int s_num) +{ + struct netlink_table *tbl = &nl_table[protocol]; + struct nl_portid_hash *hash = &tbl->hash; + struct net *net = sock_net(skb->sk); + struct netlink_diag_req *req; + struct sock *sk; + int ret = 0, num = 0, i; + + req = nlmsg_data(cb->nlh); + + for (i = 0; i <= hash->mask; i++) { + sk_for_each(sk, &hash->table[i]) { + if (!net_eq(sock_net(sk), net)) + continue; + if (num < s_num) { + num++; + continue; + } + + if (sk_diag_fill(sk, skb, req, + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, + NLM_F_MULTI, + sock_i_ino(sk)) < 0) { + ret = 1; + goto done; + } + + num++; + } + } + + sk_for_each_bound(sk, &tbl->mc_list) { + if (sk_hashed(sk)) + continue; + if (!net_eq(sock_net(sk), net)) + continue; + if (num < s_num) { + num++; + continue; + } + + if (sk_diag_fill(sk, skb, req, + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, + NLM_F_MULTI, + sock_i_ino(sk)) < 0) { + ret = 1; + goto done; + } + num++; + } +done: + cb->args[0] = num; + cb->args[1] = protocol; + + return ret; +} + +static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct netlink_diag_req *req; + int s_num = cb->args[0]; + + req = nlmsg_data(cb->nlh); + + read_lock(&nl_table_lock); + + if (req->sdiag_protocol == NDIAG_PROTO_ALL) { + int i; + + for (i = cb->args[1]; i < MAX_LINKS; i++) { + if (__netlink_diag_dump(skb, cb, i, s_num)) + break; + s_num = 0; + } + } else { + if (req->sdiag_protocol >= MAX_LINKS) { + read_unlock(&nl_table_lock); + return -ENOENT; + } + + __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num); + } + + read_unlock(&nl_table_lock); + + return skb->len; +} + +static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h) +{ + int hdrlen = sizeof(struct netlink_diag_req); + struct net *net = sock_net(skb->sk); + + if (nlmsg_len(h) < hdrlen) + return -EINVAL; + + if (h->nlmsg_flags & NLM_F_DUMP) { + struct netlink_dump_control c = { + .dump = netlink_diag_dump, + }; + return netlink_dump_start(net->diag_nlsk, skb, h, &c); + } else + return -EOPNOTSUPP; +} + +static const struct sock_diag_handler netlink_diag_handler = { + .family = AF_NETLINK, + .dump = netlink_diag_handler_dump, +}; + +static int __init netlink_diag_init(void) +{ + return sock_diag_register(&netlink_diag_handler); +} + +static void __exit netlink_diag_exit(void) +{ + sock_diag_unregister(&netlink_diag_handler); +} + +module_init(netlink_diag_init); +module_exit(netlink_diag_exit); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 16 /* AF_NETLINK */); -- cgit v1.2.3-59-g8ed1b