From b37e88407c1d78f157778d73427cd7e9e1d6369d Mon Sep 17 00:00:00 2001 From: Ivan Delalande Date: Thu, 31 Aug 2017 09:59:38 -0700 Subject: [PATCH] inet_diag: allow protocols to provide additional data Extend inet_diag_handler to allow individual protocols to report additional data on INET_DIAG_INFO through idiag_get_aux. The size can be dynamic and is computed by idiag_get_aux_size. Signed-off-by: Ivan Delalande Acked-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/inet_diag.h | 7 +++++++ net/ipv4/inet_diag.c | 22 ++++++++++++++++++---- 2 files changed, 25 insertions(+), 4 deletions(-) diff --git a/include/linux/inet_diag.h b/include/linux/inet_diag.h index 65da430e260f..ee251c585854 100644 --- a/include/linux/inet_diag.h +++ b/include/linux/inet_diag.h @@ -25,6 +25,13 @@ struct inet_diag_handler { struct inet_diag_msg *r, void *info); + int (*idiag_get_aux)(struct sock *sk, + bool net_admin, + struct sk_buff *skb); + + size_t (*idiag_get_aux_size)(struct sock *sk, + bool net_admin); + int (*destroy)(struct sk_buff *in_skb, const struct inet_diag_req_v2 *req); diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c index 67325d5832d7..c9c35b61a027 100644 --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -93,8 +93,17 @@ void inet_diag_msg_common_fill(struct inet_diag_msg *r, struct sock *sk) } EXPORT_SYMBOL_GPL(inet_diag_msg_common_fill); -static size_t inet_sk_attr_size(void) +static size_t inet_sk_attr_size(struct sock *sk, + const struct inet_diag_req_v2 *req, + bool net_admin) { + const struct inet_diag_handler *handler; + size_t aux = 0; + + handler = inet_diag_table[req->sdiag_protocol]; + if (handler && handler->idiag_get_aux_size) + aux = handler->idiag_get_aux_size(sk, net_admin); + return nla_total_size(sizeof(struct tcp_info)) + nla_total_size(1) /* INET_DIAG_SHUTDOWN */ + nla_total_size(1) /* INET_DIAG_TOS */ @@ -105,6 +114,7 @@ static size_t inet_sk_attr_size(void) + nla_total_size(SK_MEMINFO_VARS * sizeof(u32)) + nla_total_size(TCP_CA_NAME_MAX) + nla_total_size(sizeof(struct tcpvegas_info)) + + aux + 64; } @@ -260,6 +270,10 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk, handler->idiag_get_info(sk, r, info); + if (ext & (1 << (INET_DIAG_INFO - 1)) && handler->idiag_get_aux) + if (handler->idiag_get_aux(sk, net_admin, skb) < 0) + goto errout; + if (sk->sk_state < TCP_TIME_WAIT) { union tcp_cc_info info; size_t sz = 0; @@ -449,6 +463,7 @@ int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo, const struct nlmsghdr *nlh, const struct inet_diag_req_v2 *req) { + bool net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN); struct net *net = sock_net(in_skb->sk); struct sk_buff *rep; struct sock *sk; @@ -458,7 +473,7 @@ int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo, if (IS_ERR(sk)) return PTR_ERR(sk); - rep = nlmsg_new(inet_sk_attr_size(), GFP_KERNEL); + rep = nlmsg_new(inet_sk_attr_size(sk, req, net_admin), GFP_KERNEL); if (!rep) { err = -ENOMEM; goto out; @@ -467,8 +482,7 @@ int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo, err = sk_diag_fill(sk, rep, req, sk_user_ns(NETLINK_CB(in_skb).sk), NETLINK_CB(in_skb).portid, - nlh->nlmsg_seq, 0, nlh, - netlink_net_capable(in_skb, CAP_NET_ADMIN)); + nlh->nlmsg_seq, 0, nlh, net_admin); if (err < 0) { WARN_ON(err == -EMSGSIZE); nlmsg_free(rep);